RUSM 2X- Mini 1

Formation of the esophagus

- Respiratory diverticulum (RD) appears end of week 3 Esophagotracheal septum partitions RD from foregut- as this occurs locations of pharynx and esophagus are determined: - cranial to orginal level of respiratory diverticuluin is the PHARYNX - caudal to original level of respiratory diverticulum is the ESOPHAGUS - 4th to 7th week the esophagus lengthens rapidly - embryonic and fetal period there is further growth and differentiation * histological changes in epithelium are unudual - simple columnar --> stratified columnar --> muli-layered ciliated --> stratified squamous non-keratinized epithelium

Vitamin A (Comes in the various forms: Retinol, Retinoic acid, retinal, beta-carotene)

- Retinol and retinoic acid are transcription factor activators (nuclear hormone receptors or intracellular receptors) - Critical for epithelial cell development, mucus secretion, and also for normal spermatogenesis - RetinAl serves as a bound cofactor in the light-sensing proteins of the eye: rhodopsin, and opsins (the conversion of cis- to trans- retinal effected by light alters the structure of the opsin and signals light detection)

Hepatic Artery Proper dives at the porta hepatis to become

- Right Hepatic Artery - Left Hepatic Artery

Physical exam signs seen in a case of Acute Cholecystitis

- Right upper quadrant tenderness - Murphys sign (inspiratory arrest) may be present Evaluation and Management: - Abd/gallbladder US is preferred intial investigation for gallstone and acute cholecystitis - CT is preferred for evaluation of complication like gangrene, perforation, abscess, pancreatitis or peritonitis Treatment: surgical removal of the gallbladder

Accessory organs produce the enzymes a chemical agents necessary for digestion such as:

- Salivary glands: salivary amylase, lingual lipase, and lysozyme - Stomach: acid, pepsinogen, and acid lipase - Liver: lipases and bile - Pancreas: 5 proteases, 3 lipases, nucleases, amylase, and HCO3- (ex. trypsinogen and its active form trypsin) - Small intestine: 3 proteases, 5 glycosidases

Functions and Compostion of Saliva

- Salivation: water necessary to taste foods, mix with solid foods - Maintenance of oral hygiene- bicarbonate - Lubrication- speaking (when nervous- difficulty making this mucus) - Swallowing- mucus - Digestive function- enzymes (salivary amylase, lingual lipase) Composition of Saliva: - Watery hypotonic fluid contianing ions (Na+, HCO3-, Cl-, and K+), mucus, and proteins including digestive enzymes

Describe the descending part of the duodenum (2nd part)

- Secondarily retroperitoneal: immobile and covered by transverse mesocolon - important relationship to head of pancreas and gallbladder - lies right of the midline (apprx. L2) and is anterior to the hilum of the R kidney - supplied by the celiac trunk and superior mesenteric artery (b/c it is derived from the forgut and midgut) - internal features include: major and minor duodenal papillae

Where can one find serosa vs adventitia in the small intestine?

- Serosa is present where the SI lies free in the abd cavity (moveable) - Adventitia is found where the SI is attached to the body wall (fixed)

Dietary Carbohydrates include

- Simple sugars: glucose, fructose - Disaccharides: sucrose, lactose, maltose - Polysaccharides: complex carbs, starch - Dietary Fiber: can be soluble or insoluble

Internal Aspect of the Right Atrium has the

- Sinus Venarum (smooth portion) - Pectinate muscles (rough portion) - Crista terminalis (jx between rough & smooth portion) - Fossa ovalis (depressed portion) - Auricle (at times of increased venous return (ex. exercise) excess bloow flows into auricle) ** Make sure to link these to their embyrological origin

List the layers of the abd wall from superficial to deep

- Skin - Campers fascia (enlarged in obese ppl) - Scarpa's fascia (membranous) - External oblique muscle - Internal oblique muscle - Transversus abdominis muscle - Transversalis fascia - Extraperitoneal fat - Parietal layer of periotenum *** remember visceral peritoneum was talked about with appendicitis- it is NOT a layer of the abd wall- only the parietal peritoneum is

Action of Class II Agents (Metoprolol a Beta Blocker) on pacemaker cells

- Slope of phase 4 depolarization is decreased (important in SA node) - repolarization is prolonged (important in AV node)

Which vein runs with which arteries in the coronary circulation (4)?

- Small Cardiac Vein: runs with R. Marginal Artery - Middle Cardiac Vein: runs with Posterior Interventricular Artery - Great Cardiac Vein: runs with Anterior Interventricular Artery (LAD) - Coronary Sinus: runs with Circumflex artery

Sinus Venosus gives rise to the

- Smooth part of RA (sinus venarum) - coronary sinus - onlique vein of LA

What are some electrolytes and minerals that are essential for life (which are req. in larger amounts than trace minerals)

- Sodium - Potassium - Chloride - Calcium - Phosphorous - Magnesium ** electrolytes are needed in macroscopic quantities, several grams/day- they are present in concentrations near 0.1M in parts of the body *** calcium, phosphorous and magnesium are considered macronutrients as well- they are required in near-gram quantities (~0.4-1.2g) as compared to trace minerals which are generally required at an RDA below ~100mgs some even less than 1mg/day

Presentation/Symptoms of Acute Pancreatitis

- Sudden onset unrelenting epigastric pain, sharp in nature - Pain often radiates to the back - nausea and vomiting, anorexia are common - signs of volume depletion in the setting of decreased oral intake as well as potential extracellular or third-space fluid losses - Acute pancreatitis is commonly caused by gall stones or alcoholism

Superficial veins of the anterolateral abd wall

- Superficial epigastric veins: drain directly into GREAT saphenous vein, travels with superficial epigastric artery - Thoracoepigastric veins: drain directly into the lateral thoracic vein, does NOT have a corresponding artery - Periumbilical veins: are located around the umbilicus, communicate (aka anastomose) with the thoracoepigastric veins, communicate with the paraumbilical veins

Origin of the Posterior Intercostal aa

- Superior (supreme) intercostal aa: which arise from the Subclavian artery --> give rise to the 1st and 2nd POSTERIOR intercostal aa. - Thoracic (descending) aorta: gives rise to the 3rd-11th POSTERIOR intercostal aa. *** This is relevant in the collaterl circulation associated with co-arctation of the aorta "narrowing of the aorta"- will see this in resp.

Deep arteries of the abd wall

- Superior epigastric artery: branches directly from the internal thoracic artery, travels deep to rectus abdominis muscle (supplies supeiror part of anterolateral wall) - Inferior epigastric artery: branches directly from the external iliac artery, travels deep to rectus adbominis muscle (supplies medial part of anterolateral wall) ****forms an anastomosis (connection) with the superior epigastric artery

Deeps veins of the anterolateral abd wall (same as deep arteries)

- Superior epigastric veins: drain into the INTERNAL thoracic ceins, travel with the superior epigastric artery - Inferior epigastric veins: drain directly into the EXTERNAL iliac veins, travel with the inferior epigastric artery - Paraumbilical veins: are located parallel to the umbilicus, drain into the hepatic portal vein ** important in the liver

Describe the surface and neck mucous cells of the stomach

- Surface mucous neck cells are clear staining: the mucous gets lost during the processing, so the cells would appear very clear (secrete an INSOLUBLE type of mucus) - Mucous neck cells are much smaller than surface cells: they have more prominent nuclei, but they are small (secrete a SOLUBLE type of mucus) (these are found in the fundus/body of the stomach)

Describe the ductal system of the Major Salivary Glands

- The glands have a dense CT capsule - CT septa penetrate into the gland from this capsule to separate it into lobes and lobules - the Duct System includes intralobular ducts (within the lobules), interlobular between the lobules, lobar ducts and the main duct ** the duct system has reabsorption capability A. Intralobular Ductal System - secretory acini empty into intercalated ducts which are lined by cuboidal (come cells low cuboidal) epithelium - intercalated ducts join to form a striated duct- these are characterized by basal striations (infolding of the basal membrane and associated elongated mitochondria) Actively transport Na+ ions from saliva into the extracellular space out into blood stream - bringing sodium ions back into the body this intralobular ductal systme empties into the interlobular ducts B. Interlobular Ductal System - ducts from each lobule drain into the interlobular ducts - variable lining: however before emptying into the oral cavity, main duct of each gland is lined by stratified squamous non keratinized epithelium ---------- Acinus collectively secrete fluid (mucus and/or serous) --> intercalated ducts --> striated ducts (remember intercalated and striated ducts are part of the intralobular ductal system) --> interlobular duct --> out through main duct

What are two important functions of the liver that have to do with bile

- The liver produces and secretes bile acids and bile pigments - The liver does excretion of heavy metals, cholesterol and bile pigments, drugs, and hormones

Digestion is the breakdown of foods into usable and absorbable components

- To take up proteins, carbs, and nucleic acids required specific transporters - AAs are generally taken up and mono- and di-peptides - Carbs are generally taken up as monosaccharides - Nucleic acids are typically taken up as bases and phosphates and sugars - Fats are taken up in micellar fusion with enterocytes or by direct diffusion. However, the fats must be reduced to diacylglycerides, monoglycerides or fatty acids. Free glycerol is NOT a common product for lipases

Right Ventricle

- Trabeculae Carneae (rough portion) - Conus arteriosus/infundibulum (smooth portion): leads to the pulmonary trunk through the pulmonary valve ** these two have two diff. embryological origins but NO raised ridge separating them like the crista terminalis separates the rough and smooth portions in R atrium - Tricuspid Valve: Chordae tendineae "heart strings" & 3 papillary muscles (anterior, posterior, septal (May be more than one septal one)) - Septomarginal Trabeculae (AKA moderator band): contains right branch of the AV bundle

Remember that the testes need to descend to the scrotum and that they do this with the help of the gubernaculum- note that there are several layers in the testes way to the scrotum, which of these layers become coverings of the spermatic cord and scrotum?

- Transversalis Fascia --> becomes the internal spermatic fascia - Internal Abdominal Oblique Muscle --> becomes the cremaster fascia and muscle (cremaster muscle is striated and innervated by the genital branch of the genitofemoral nerve to elevate the testes (GSE)- it draws the testis closer to the body for protection - External Abdominal Oblique Muscle --> becomes the external spermatic fascia - Scarpa's Fascia - Skin ** the above contributions change names as they get lower * NOTE: the Transversalis Abdominis DOES NOT contribute to the coverings of the spermatic cord and scrotum

Chronic Gastritis (autoimmune)

- Typically in body and fundus of stomach - autoimmune reaction to parietal cells (esp. H+, K+-ATPase) * parietal cells make acid and intrinsic factor - Achlorhydria (low acid) resulting in hypergastrinemia - Antral endocrine cell hyperplasia: in parallel to mucosal atrophy and response to reduced acid production - Vit B12 deficiency due to low intrinsic factor - reduced serum pepsinogen I (chief cells lost with parietal cells) Morphology: - diffuse mucosal damage with decreased oxyntic (acid-producing) mucosa in body and fundus - atrophy with intestinal metaplasia (increased risk adeno carcinoma) - neuroendocrine (NE) hyperplasia- can lead to multiple carcinoid tumors

Sub-actue inflammation

- UNRESOLVE acute inflammation - ONGOING tissue damage - infectious/irritant agent NOT CLEARED - features of acute and chronic inflammation - reparative process with FIBROSIS (laying down of fibrous tissue)

What are some complications of acute inflammation?

- Ulceration (due to damage of the lining tissue of the organ) - Abscess formation (if inflammation has not cleared microorganism) - Subacute inflammation (acute & chronic)- if acute inflammation doesnt resolve - Chronic inflammation (resulting from acute) - Perforation (fistula, abscess, serositis) * fistula= abnormal tract between two organs where you have drainage of exudate

Inflammatory Bowel Disease

- Ulcerative colitis: nonspecific inflammatory bowel disease of unknown etiology that affects the mucosa of the colon and rectum - Crohns Disease: nonspecific inflammatory bowel disease that may affect any segment of GI tract ** both of these above are characterized by inflammation with ulcers in the lower bowel leading to diarrhea, often mixed with blood - Indeterminate colitis: 15% Pts with IBD impossible to differentiate

Circulatory changes at birth

- Umbilical arteries close a few minutes after birth due to contraction of SM in the walls of these vessels - permenant closure by fibrous proliferation takes 2-3 months After birth: proximal poritons of umbilical arteries are retained- to yield distal segment of internal iliac arteries and superior vesicle arteries - distal portions of umbilical arteries are obliterated to yield R/L medial umbilical ligaments

Reasons for acute inflammation in the liver

- Viruses: Hepatitis (A,B,C), Coxsackie - Bacteria, fungi, parasites: ascending (up biliary tract), vascular seeding, direct invasion penetrating injury - Drugs (acetaminophen, Halothane, chlorpromazine) - Toxins (aflatoxins), Alcohol "chemically induced" - NON alcoholic fatty liver disease (associated with metabolic syndrome)

Reasons for chronic inflammation of the liver

- Viruses: Hepatitis B and C - Tuberculosis, Autoimmune Hepatitis, Sarcoidosis (another autoimmune disease) - Haemochromatosis (iron) and Wilsons Disease (copper)- both of these are inherited - Alcohol - NON alcoholic fatty liver disease

What are the primary components of Chief Cell Secretion?

- Water, ions, and pepsinogen (water follows ions into lumen- pressure at the bottom of the pit increases) - Relatively neutral pH - Water follows ions into lumen as in other secretory cells - Exocytosis of pepsinogen Chief Cells are located mostly in deeper part (base) of the gastric pit: - this is true of most but NOT all chief cells - deeper fluid pushes gastric acid-rich fluids out of the gastric pit - pepsinogen is inactive in the gastric pit (it is activated to pepsin by concentrated stomach acid in the gastric lumen) - protective effect on pit epithelium

Sources of Vit B7, Biotin

- Yeast, liver, eggs, peanuts, milk, chocolate, and fish Deficiency: virtually unkown (it is rarely deficient) - eating raw eggs, which contain avidin, can deplete biotin (20 raw eggs/day needed) - avidin binds biotin with very high affinity and this binding is utilized in many biotech applications (ELISA, western blots, etc.) Sxs: Glossitis, dermatitis, appetitie loss and nausea

Factors that increase Central Venous Pressure

- a decrease in CO (ex. due to decreased HR or SV- i.e. LV HF) will lead to blood backing up in venous circulation - an increase in blood volume (i.e. renal failure or fluid retention through activation of RAAS) - venous constriction (via symp activation of veins, or by circulating vasoconstrictor substances (ex. catecholamines and angiotensin II) decreases venous compliance- which increased VP - changing position from standing to supine - arteriolar dilation (during withdrawl of symp tone or w/ arterial vasodilatory drugs) causes increased flow of blood from the arterial to venous side- increases proportion of blood in venous system and CVP (this is what occurs when heart is functioning normally) - muscle contraction of limbs and abdomen compresses veins (i.e. decreases compliance) and due to one-way venous valves moves blood back to the heart in the thoracic compartment thereby increasing thoracic blood volume and CVP

Lesser sac

- a division of the peritoneal cavity - AKA omental bursa - NO organs here - small compartment that is lined with peritoneum and is positioned: BEHIND the stomach and greater omentum and INFRONT of the peritoneum and pancreas

Phosphatidyl-inositol

- a relitively minor constituent in mammalian membranes the inositol headgroup can be phosphorylated, and is involved in intracellular signaling (ex. PIP2, PIP3) - IP3 acts to release calcium - PIP3 acts as a signaling molecule

Cirrhosis

- a result of chronic inflammation of the liver - diffuse transformation of the liver into regenerative parenchymal nodules surrounded by fibrous bands (hepatocyte necrosis with nodular regeneration) *** thick fibrous bands seen surrounding nodules in histological slides Etiology: - chronic hepatitis associated with alcohol, non alcoholic liver disease, Hepatitis B & C, autoimmune hepatitis, hemochromatosis, Wilsons disease, primary biliary cholangitis (autoimmune), cholelithiasis (gallstones) Complications: - Liver failure - Hepatocellular carcinoma (if 10yrs or more of Cirrhosis)- will show anaplastic changes on histological slide

What is found in the epigastric region

- abd esophagus - stomach - pancreas - small intestine - liver - gallbladder - R and L kidneys - R and L adrenal glands

Early signs and symptoms of alcoholic liver disease

- abd pain, nausea and vomiting, diarrhea, loss of appetite, jaundice, edema, fever, itchy skin, curved fingernails, weight loss, muscle wasting Diagnosis - can be challenging- early stages of ALD may be asymptomatic - history of alcohol consumption - AST > ALT (imperfect correlation) - hepatomegaly - anemia - elevated gamma glutamyl transferase ALD progression Healthy liver --> Steatosis/fibrosis alcoholic steatohepatitis --> liver cirrhosis --> liver cancer * 90-100% of alcholics have steatosis * 10-35% show alcholic hepatitis * 8-20% - cirrhosis * 1-2% of cirrhotics/yrs develop HCC (liver cancer)

Gastro-Esophageal-Reflux-Disease (GERD)

- acid from stomach refluxes into the esophagus - esophageal mucus protects the esophageal mucosa (initially but if persistant without protection it can progress to the pathological condition: Barrett's Esophagus) Barrett's Esophagus: Metaplasia: stratified squamous epithelium is replaced by simple columnar epithelium- you will see gastric-type mucosa above the gastroesophageal junction - Congenital: NOT precancerous - Acquired: precancerous * thus: chronic "heartburn" should not be ignored

Diagnositic Considerations for Abd Pain

- age of patient - gender (for female patient date of last menstrual period) - time and mode of onset of the pain - pain characteristics: location, radiation, severity? poorly defined? localized? colicky? - duration of symptoms: acute or chronic? - associated symptoms and their relationship to the pain, for example, nausea, emesis, and loss of appetite - diarrhea, constipation, or other changes in bowel habits (nature of stools/changes)

Disorders of the liver and small intestine

- alcoholic liver disease - cholelithiasis/ cholecystitis (gallstones) - malabsorption of nutrients secondary to pancreatic failure (ex. pancreatitis, exocrine pancreatic insufficiecy) - malabsoprtion by the small intestinal mucosa - from failur of either enzymes or transport proteins on apical (brush border) membranes of intestinal enterocytes) - excess secretion of intestinal fluids from small intestine (discussed in more detail under diarrhea, large intestinal disorders) - antiperistalsis and power propulsion (two ways to clear small intestine of inappropriate irritant substances) * antiperistalsis is not a disorder per se but it is often associated with vomiting- same with power propulsion - might be associated with diarrhea or an external cause but not a disorder itself - they are listed as conseq/ effects of other conditions which are disorders- such as intestinal obstruction, gastric inflammation, etc.

Pathological Appearance of an Acute Appendicitis

- attraction of polymorphs into the area - compromisation of blood supply to organ - damage to lining or mucosa of appendix "ulceration" - death of tissue "necrosis"

Characteristics of MALIGNANT tumors

- cells CAN spread - usually GROW RAPIDLY - often invade basal membrane that surrounds nearby healthy tissue - can spread via bloodstream or lymphatic system, of by sending "fingers" into nearby tissue "protrusions" - may recur after removal, sometimes in areas other than the original site - cells have abnormal chromosomes and DNA characterized by large, dark nuclei; may have abnormal shape - can secrete substances that cause fatigue and weight loss (these hormonal effects can cause paraneoplastic syndrome) - may req. aggressive treatment including surgery, radiation, chemotherapy, and immunotherapy medications

Characteristics of BENIGN tumors

- cells tend NOT to spread - most grow SLOWLY - do not invade nearby tissue - do not metastasize (spread) to other parts of the body - tend to have CLEAR BOUNDARIES - under a pathologists microscope, shape, chromosomes, and DNA of cells appear normal - do not secrete hormones or other substances (an exception: pheochromocytomas of the adrenal gland) - may not req. treatment if not health-threatening - unlikely to recur if removed or req. further treatment such as radiation or chemotherapy

Why is the Suspensory Ligament of the Duodenum (aka Ligament of Treitz) clinically significant?

- connects the duodenum to the diaphragm and the posterior abd wall - facilitates with the movement of the intestinal contents - marks the duodenojejunal flexure- junction between the duodenum and jejunum Ligament clinically divides the GI: Upper GI tract bleed is proximal: - blood would appear in vomit - stool would typically be dark and "tarry" Lower GI tract bleed is distal - blood would only appear in the stool

Peritoneal ligament include

- coronary ligament - falciform ligament - round ligament of liver - hepatogastric ligament - hepatoduodenal ligament - gastrophrenic ligament - gastrosplenic ligament - gastrocolic ligament - splenorenal ligament *** ligaments can connect organs to another organ and an organ to the abd wall

What is found in the left iliac/ left inguinal region

- descending colon - sigmoid colon - small intestine - left ovary and uterine tube in females

What are ways we can get cholesterol in our bodies

- dietary cholesterol (chylomicron remnants) - cholesterol from extrahepatic tissues (HDL) - excretion in bile (50% is re-absorbed, this amt is typically higher then dietary cholestrol) - conversion to bile salts - de novo synthesis of cholesterol in the liver * dysfunction of cholesterol reg. implicated in cardiovascular disease * cholesterol is carried in body in lipoproteins, such as chylomicrons, low density lipoprotein, and high density lipoprotein *NOTE: cholesterol cannot be metabolized for energy, it is only lost by excretion

Functions of gastric secretions

- digestion of proteins and lipids (pepsinogen and HCl, and gastric lipase) - protection of stomach from gastric acid (HCO3- and mucus)- made by some cells of the stomach, but needed to protect other cells - protect VitB12 from intestinal digestions (intrinsic factor) - destroy bacteria and other micro-organisms (HCl)

Foregut gives rise to

- distal esophagus - stomach * spleen is not a foregut structure but found in relation to these structures - pancreas - liver - gallbladder - duodenum: 1st and (proximal) 2nd part ****** Arterial supply for these= celiac trunk branches from the abd aorta at the level of T12

What structures are dervied from the foregut?

- distal esophagus - stomach - spleen (found in abd- associated with the foregut but NOT derived from it) - pancreas - liver - gallbladder - duodenum: 1st and (proximal) 2nd part * supplied by celiac trunk branches from the abd aorta at the level of T12

Disorders of the oral cavity, pharynx, and esophagus

- dysphagia - achalasia - gastroesophageal reflux disease - barrett esophagus

Role of Carbohydrates

- energy - glycolipid/glycoprotein building blocks - anti-ketotic (prevent ketone body production) - protein sparing (prevents protein breakdown) - proper digestion (fiber)

Mediterannean diet

- focused on US foods modified to reflect health benefits of mediterannean style diet - more seafood and fruit, less dairy - no change in oil - calorie limits for other uses (~260) non-nutrient dense foods - 2.5 cups of fruit as opposed to the US recommeded 2 cuprs - 6.5oz of protein such as fish compared to US 5.5oz - 2 cup of dairy compared to the US recommended 3 cup ** high in fruits ** lowest in dairy ** highest in proteins

Paleo Diet

- focuses on evolutionary diet- what our ancestors ate before us - high in lean meat (~37% protein) - high in nuts, natural fruits, fiber - carbs ~40% - fats ~20% - avoid foods that are a result of modern agricultural products, and processed foods and simple sugars Considerations: - ppl likely have adapted since the paleolithic - is consistent with eating less refined and porcessed foods and more fiber * no evidence of being better than normal diet

Disorders of the stomach (related to gastric injury- leading to gastritis)

- gastric injury leading to gastritis - peptic ulcers: related to H. pylori and all other causes - pernicious anemia (this was seen in 1st semester!) - vomiting ( nausea, antiperistalsis, acid- base consideration associated with prolonged or freq. vomiting)

Vomiting is caused by

- gastric irritation - vestibular function/ stimuli- motion sickness - gastric outlet constriction * vomiting= means by which the upper gastrointestinal tract rids itself of its contents when almost any part of the upper tract becomes excessively irritated, over distended, or over excitable- excessive distention or irritation of the duodenum provides an especially strong stimulus for vomiting it is preceded/ accompanied by: - tachypnea - copious salivation - dilation of pupils - sweating - pallor - nausea

Since more than one protease is needed to limit digest a dietary protein

- genetic loss or reduction of one is compensated for by other proteases - proteases are made as zymogens or co-secreted with an inhibitor

Congenital Megacolon (Hirschsprung Disease)

- grossly dilated colon filled with gas - ENS excitatory and inhibitory neurons are absent from the myenteric and submucosal plexi, usually in a segment of distal colon - in the affected segment, the lumen becomes narrowed due to tonic contractions of smooth m. - the inhibitory signals that are necessary for smooth m. relaxation there cannot occur - the passage of fecal material is hindered, and it accumulates proximal to the constriction- as a result the proximal colon becomes chronically distended (megacolon)- the normal reflex relaxation of the internal anal sphincter in response to rectal distension cannot be elicited

large intestine looks like it has what kind of glands

- hand facing down "test tube glands" these are mucus secreting glands: lower 2/3 consists entirely of goblet cells

Gastrin is a hormone with seemingly opposing functions it both

- increases motility and increases pyloric sphincter tone - Net effect of this hormone: is to increase churning and mixing of gastric contents- facilitating mechanical and chemical digestion - Taken alone, its net effect is: Gastric Emptying - Other modulators will come into play to determine whether emptying actually occurs

Disorders of large intestine

- inflammatory bowel disease (IBD) secondary to either ulcerative colitis or crohns disease - congenital megacolon (Hirshsprungs Disease) - acute diarrhea - diverticular disease/ diverticulosis

Describe the superior first part of the duodenum

- intraperitoneal (highly mobile) - duodenal cap or ampulla is continuous with the pylorus of the stomach (apprx. L1)- anything entering stomach enters the duodenal cap - hepatoduodenal ligament (one of the thickenings associated with the lesser omentum) connects superiorly and supports the duodenum - greater omentum connects inferiorly - supplied by celiac trunk (bc it is a foregut derivative)

ALL abdominal viscera have a relationship to the peritoneum- they can either be

- intraperitoneal: within - extraperitoneal: outside

Describe the Mucosa of the esophagus

- lined by NON-keratinized stratified squamous epithelium - lamina propria= a thin band - Cardiac glands are present which secrete mucus - muscularis mucosae: upper absent; then a single longitudinal layer

What is found in the R lumbar region

- liver - gallbladder - right kidney - ascending colon - small intestine

What is found in the right hypochondriac region

- liver - gallbladder - right kidney - right colic flexure (ascending and transverse colon)

The lamina propria of the small intestine consists of

- loose CT that is packed with blood vessels, lymphatic capillaries, smooth muscle cells, cellular, solitary lymph nodules * this lamina propria leads to the final layer of the mucosa which is the Muscularis Mucosae that is composed of a thin layer of smooth m. * muscularis mucosae leads to the submucosa

two places for resistance to flow in the stomach

- lower esophageal sphincter (dont want food/acid to pop up into esophagus) - pylorus

Greater Sac

- main compartment of the peritoneal cavity - extends from the diaphragm to pelvis - NO organs are in this potential space * in males: peritoneal cavity is completely closed * females: there is an opening in the peritoneum through the uterine tubes (R/L uterine tubes)

Superficial arteries of the abd wall

- main vessels are the superficial epigastric a. (supplies superficial pubic and umbilical regions) and the superficial circumflex iliac which are branches of the femoral artery

Cholelithiasis (Gallstones)

- most composed of calcium bilirubinate and cholesterol - can obstruct biliary flow and result in pain, poor tolerance of large fatty meals, retention of biliary constituents, and if left untreated liver injury Causes: - too much absorption of water from bile or of bile acids from bile - too much cholesterol in bile - inflammation of epithelium * Symptoms vary depending on location of the gallstones: - gallstones in gallbladder- asymptomatic - obstruction of cystic duct-> acute cholecystitis and biliary colic - obstruction of hepatic duct --> asymptomatic or may cause jaundice and signs of inflammation of bile duct and the liver - obstruction of common bile duct --> biliary colic and jaundice - obstruction of ampulla of vater or the ampullary part of common bile duct --> jaundice and signs of pancreatitis

Describe the fourth/ascending part of the duodenum:

- mostly retroperitoneal - terminates at the duodenojejunal flexure (or turn/angle) - closely related to the abd aorta (abd aorta lies posteriorly) - ascends back up to apprx. L2 - supplied by the superior mesenteric artery - supported by the suspensory ligament: The ligament of Treitz * ulceration posteriorly can erode into the posterior vessels (aorta) or anterior (superior mesenteric artery)

Irritable Bowel Syndrome (IBS) is considered one of many "functional GI disorders". Rome IV defines these as disorders of gut-brain interaction classified by GI symptoms related to any of the following:

- motility disturbance - visceral hypersensitivity - altered mucosal and immune function - altered gut microbiota - altered CNS processing

Causes of groin herniation

- obestiy - preg. - heavy lifting - chronic obstructive pulmonary disease - strianing (ex. constipation) - congenital CT disorders) - defective collagen synthesis - cigarette smoking - ascites * anything the causes the abd wall to weaken * NOTE: chance of recourrence after repair is 10-15%

Remnants of the LEFT sinus horn form the

- oblique vein of the left atrium and - the coronary sinus ----- The RIGHT sinus horn enlarges and is incorportaed into the posterior wall of the right atrium ** remember the Right Horn of Sinus Venosus gives rise to the smooth part of the right atrium (sinus venarum) *** The left horn of the Sinus venosus gives rise to the coronary sinus

What types of cells can be found in the fundus/body of the stomach

- pariteal cells and chief cells are main ones ------ Fundus/body of stomach has - shallow pits and deep glands (straight) - neck and base of the glands are histologically distinct Neck: - mucous neck cells - lorts of Parietal cells (aka oxyntic cells): produce HCl and intrinsic factor (which is important for B12) - stem cells (aka regenerative cells, divide and diff. to for other cell types) (these are also found in the isthmus) Base (bottom): - few parietal cells - chief cells (aka zymogenic cells): secrete pepsinogen, renin and lipase) [ chief cells > b/c secrete fluid thats not active till mixed with acid ] - mucus cells - enteroendocrine cells (EEC)

Dysbiosis (abnormal microbiota) can lead to diseases caused by

- pathogenic overgrowth - increased gut permeability - loss of anti-inflammatory peptides - increased NT (made by microbiota) - loss of choline - increased trimethylamine (TMA), dimethylamine (DMA) and trimethyl N-oxides (TMAO) ----- Ulcers= overgrowth of H.Pylori, erosion of mucosal layer and cells Travelers Diarrhea= overgrowth of Giardia, erosion of brush border and increased permeability Auto-brewery Syndrome (ABS)= overgrowth of yeast, production of alcohol in the gut C. diff- overgrowth of Clostridiodes Difficle, intestinal infection and perforation, megacolon (due to prolonged antibiotics- can treat with putting in healthy microbiota) Irritable Bowel Syndrome (IBS), Inflam. Bowel Disease (IBD), and Celiac Disease (CD)= organism ratios change; permeability and inflammation Artherosclerosis= TMA, DMA, TMAO and low choline (increase foam cells which cause artherosclerotic plaques), increased growth and cell division of foam cells

Factors influencing RMR (resting metabolic rate)

- proportion of lean body mass: 5 % increase in basal metabolism for athletes and women who have more fat in proportion to muscle than men have 5-10% lower metabolic rate than men of the same weight and height - abnormal states of starvation and malnutrition: decreases BMR Things that increase RMR: - hyperactive thyroid - fevers: 7% for each degree F* or .55C in body temp - preg. and lactation - 5-20% higher in tropics: exercise in temp greater than 86 *F imposes additional metabolic load of 5 % owing to increased sweat gland activity - physical activite - diseases involving increased cell activity (ex. cancer, cardiac failure) - growth hormone raises RMR by 15-20% and stimulates cell metabolism- it rises during 1-5yrs, levels off and rises again just before and during puberty - rises in cold climates as compensatory mechanism to maintain body temp Things that decrease RMR - sleep by 10%

For vomiting, in your history please make sure that you have probed for:

- quantity, frequency, periodicity - color - character: projectile, recurrent, cyclic - aggravating and alleviating factors - associated factors

Dietary Protein is principally used for

- rebuidling proteins in the body and energy - rebuilding body proteins takes priority, excess consumption beyond that need is used for energy - proteins are the main nitrogen containing food ** we are said to be in positive nitrogen balance- more dietary protein used for protein syn than it is degraded - happens in preg, growth, and after exercise * Negative nitrogen balance: protein breakdown> protein consumption- this occurs during fasting when proteins are broken down to support gluconeogenesis or during long or intense exercise * whether somone is in positive or negative nitrogen balance can be measured by comparind urine urea amounts to the amount of protein consumed

HDL

- recycling, uptake of cholesterol - synthesized in the liver and in the intestines - reservoir for several apolipoproteins - undergoes lipid exchange with VLDL - Undergoes apolipoprotein exchange with chylomicrons, VLDL, IDL - delivers cholesterol and fatty acids for TG to liver and is recycled

Mucosa is found at the main portals of entry of microorganisms such as:

- respiratory tract - gastrointestinal tract - genitourinary tract *** these areas are covered by mucus which is made of mucins (glycoproteins) which are a sticky, anti-microbial layer which serves to 1. protect the epithelium and 2. trap and destroy microorganisms

Ethanol metabolism

- results in massive increase in the concentration of cytosolic NADH in the liver - the ethanol-mediated increase in NADH causes the intermediates of gluconeogenesis to be divereted into alternate reaction pathways, resulting in decreased synthesis of glucose - make lactate and malate * in fasting state- excess NADH diverts pyruvate to lactate and OAA to malate and reduces their concentration - this can cause hypoglycemia - by lowering pyruvate and OAA conc. which are at the start-point of gluconeogenesis- the effective substrates for gluconeogenesis are reduced - by preventing gluconeogenesis, a person who goes out drinking without eating can have a hypoglycemic episode- the symptoms of alcohol intoxication and hypoglycemia can be similar * uses alcohol dehydrogenase (ADH) - this mechanism applies to moderate amounts of alcohol

The 5 major GI hormones are ALL

- secreted by the stomach or intestine in response to gut signal - have significant effects on some aspects of gastric, pancreatic/biliary, and intestine functions * the ones secreted mostly by the duodenum that INHIBIT gastric function have a special class name: "Enterogastrones" ALL of these are peptide/protein hormones - like other peptide hormones, these 5 are secreted acute, act quickly, and metabolized quickly These hromones inclue: 1. Gastrin 2. Cholecystokinin (CCK) 3. Secretin 4. Glucose-dependent insulinotropic polypeptide (AKA Gastric inhibitory peptide AKA GIP) 5. Motilin *** these 5 are made in the gut and stay - Minor hormones include: Ghrelin, Peptide YY (PYY), Glucagon-like peptides 1 and 2 (GLP-1, GLP-2), and many others

List the mucosal immune factors found in the mouth

- sloughing cells - flow of saliva - lysozyme - resident microflora

Action of Class IV Agents (CCBs) on pacemaker cells

- slows the AP upstroke in nodal tissue - decrease excitability of SA node - prolongs AV node conduction (high dose can produce AV node heart block) ** Class IV antiarrythmics are useful in treatment of arrhythmias that involve re-entry through the AV node, but high doses of Ca2+ channel blockers can prolong AV conduction to the extent that heart block occurs

What is found in the Right iliac/ Right inguinal region

- small intestine - appendix - cecum - ascending colon - R ovary and uterine tube in females

What is found in the hypogastric/ suprapubic region

- small intestine - sigmoid colon - rectum - urinary bladder - uterus, ovaries, and uterine tubes in females - prostate, seminal vesicles and vas deferenc in males

What is found in the umbilical region

- stomach - pancreas - transverse colon - small intestines - R and L kidneys

Presentation/symptoms of a case of Acute Appendicitis

- sudden onset of abd pain, loss of appetite, nausea, vomiting, fever, in this sequence - vomiting, when it occurs is watery, not bilious - shifting of the pain from umbilical to the R lower abd - abd movements are painful - pt does not want to move the torso

Sources of VitD, cholecalciferol are

- sunlight conversion in the skin - fatty fish, liver, egg yolk. In fortified milk Deficiency can be due to: - insufficient sunlight: northern latitudes - insufficient diet Can Cause: - Rickets in childhood, loss of bone mineralization (soft bones due to incomplete mineralization) - Osteomalacia in adults- demineralization of bones * lack of VitD leads to lack of systemic calcium which leads to de-mineralization of bones in longterm TOXICITY- in high does (100x RDA) - stored in the body (fat soluble) - sxs: loss of appetite, nausea, thirst, stupor - hypercalcemia: deposition of calcium in many organs

What are some key points about cholesterol

- they are all circulating in blood contained in lipoproteins, mainly LDL and principally as cholesterol esters - they are necessary in syn. of steroid hormones, as precursors for bile acis, and as membrane constituents - high levels of plasma cholesterol (specifically LDL) is strongly associated with atherosclerotic plaque formation and cardiovascular disease

What are some signs during a Physical Exam that a patient has Peptic Ulcer Disease

- upper abd and mid-epigastric tenderness to palpation - NO gaurding or rebound unless perforation has occurred Evaluation and Management: - Test (H. Pylori) and treat (PPI) for low risk patients - Endoscopy when symptoms do not improve or "alarm" symptoms are present - Surgery for persistent ulcer, bleeding, perforation, peritonitis

Lipids are generally

- water INSOLUBLE - can form small vesicles or micelles Lipid Plasma Transport - requires carrier method to make soluble - formation of particles Lipoprotein Ferry Lipids - Lipoproteins exsist to ferry lipids, TAG, and other hydrophobie thing that are water insoluble - Lipoprotein structues: a shell that is a monolayer of phospholipis and cholesterol (looks like 1/2 of a lipid bilayer), apolipoproteins embedded in the shell, a hydrophobic core ** lipoproteins are mixtures of lipids and proteins, also TAGs, cholesterol, and cholesterol esters- their purpose is to traffic lipids through the body Apolipoproteins: are the proteins that constitute part of the lipoprotein particle: aid in structure, identification, receptor uptake ligand, interaction with enzymes

Bile salts have free

-COO^- or are conjugated with taurin or glycine Exs: - Glycocholic Acid (w/ glycine) - Taurochenodeocycholic acid (w/ taurine) these are secreted into gall bladder and SI- in SI they can be deconjugated by bacterial enzymes and converted to secondary bild acids (deoxycholic acid and lithocholic acid) - these are detergennts and help disperse fats for breakdown and absorption by the intestine * a modest percentage (2-3% ~0.5g) is not re-absorbed, but excreted- everything other than this can be taken back up into the liver

Prokinetic Drugs

-Drugs that can enhance coordinated GI motility and transit of material in the upper GI tract - No significant effects on lower GI motility - Improve gastric emptying Ex. Metoclopramide MOA: - Dopamine D2-receptor antagonist - Also involves 5HT4 receptor agonism: vagal and central 5HT3 antagonism, and possible sensitization of smooth m. muscarinic receptors Pharmacological effects: - enhances gastric emptying - stimulates cholinergic smooth muscle in GI tract - increases esophageal peristaltic amplitude - increases lower esophageal sphincter pressure - enhances gastric emptying - potent antinausea and antiemetic action (due to blockade of D2 receptors in the CNS) Pharmacokinetics: - oral, IV, IM - conjugated in liver and eliminated renally - half life= 4-6hrs ** Can be used in Diabetic Gastroparesis

Epithelial cells of the respiratory tract can also

-differntiate between commensales and pathogens - secrete antimicrobial peptides and proteins - secrete cytokines (pro-inflammatory: IL-1, IL-6, TNF-alpha, IL-15) (anti-inflammatory: IL-10, TGF-beta to limit inflammation) -- ** remember that the mucosal system can also do cross-presentation like what we saw last semester

Resting Metabolic Rate (RMR) in females is

0.9 kcal/kg/hour ex. RMR of a female weighing 65kg= 65 x 0.9 x 24= 1404kcal/d

In nutrition a Cal is acutally = to

1 kCAL - So Cal refers to kcal

Resting Metabolic Rate (RMR) in males is

1 kcal/kg/hr ex. RMR for a 70kg man= 70kgx 1 x 24= 1680kcal/d

Describe Autonomic Regulation of Salivary Secretion

1. "Non-Gut" signals such as - Stimuli like: smell, sound, sight, taste, chewing - Inhibitors like: sleep, fatigue, fear ast on the "Higher centers of the brain - these go on to act on the control site- Medullary Salivatory Nucleus NOTE at same time "Gut signals" like GI sensory inputs are ALSO working on the medullary salivatory nucleus then you can get either - Sympathetic (enzyme rich- thick gooey secretion)- you get thick gooey saliva when you are nervous or - Parasympathetic (watery- thn secretion) 2. either or will act on the salivary glands - leads to increased blood flow and secretion and thus increased salivary flow *** the final compositions varies *** the control system in brainstem (Medullary Salivary Nucleus) controls quantity and quality of saliva (aka how "thick" or "watery" the saliva is by varying how much SNS vs. PNS stimulation goes to the acini * Many signals modulate this flow, ALL coordinated by this nucleus - to shut off flow to MINIMUM- turn off BOTH SNS and PNS motor signals to salivary glands ((so to turn OFF flow, just turn off both PNS and SNS)) - to increase flow to the MAXIMUM, INCREASE both SNS and PNS motor signals to salivary glands

Thoracic Wall Skeleton consists of

1. 12 Ribs and costal cartilages (R & L so its 12 pairs) 2. Sternum 3. 12 Thoracic Vertebrae 4. Joints of the thoracic wall

What is to be expected during a Virtual Colonoscopy?

1. 24 hrs before test: clear out bowls with laxatives, enema, all liquid diet 2. Night before test: drink contrast medium so colon will be visible in xray 3. Day of test: tube inserted 2 inches into rectum to inflate colon for imaging 4. CT scans taken for 10-15 minutes

Barrett's esophagus (aka Barett's syndrome, CELLO (columnar epithelium lined lower esophagus) or colloquillary as Barrett's:

1. ACQUIRED - refers to abdnormal change (metaplasia) in the cells of lower end of the esophagus thought to be caused by damge from chronic acid exposure, or reflux esophagitis - premalignant condition - 1-5% of patients with Barretts esophagus go on to develop cancer 2. CONGENITAL - developmental process arrested

What are the big 4 Neurotransmitters associated with the ENS motor neurons

1. Acetylcholine (ACh) 2. Substance P (SP) - these are from STIMULATORY motor neurons of the myenteric plexus - produces smooth muscle contraction at target tissue 3. Vasoactive Intestinal Peptide (VIP) 4. Nitric Oxide (NO) - these are from INHIBITORY motor neuorns in the myenteric plexus - INHIBITS smooth muscle contraction at target tissue- so promoted relaxation **** when inhibitory ones are on, stimulatory are off and vice versa NOTE: Norepinephrine (NE) from SNS usually inhibits smooth muscle contraction BUT ENS neurons do NOT typically use NE as a neurotransmitter- if it is present it came DIRECTLY from brain/spinal cord using higher motor neuron to lower motor neuron (blood vessel control done by NE)

2 brances of the Left Coronary Artery

1. Anterior interventricular (LAD- left anterior descending) - Diagonal branch - Septal branches 2. Circumflex - Left marginal

Aorta comprises of

1. Ascending Aorta - fromed by partitioning of the outflow tract 2. Arch of the aorta - formed by partioning of the outflow tract and left 4th aortic arch artery 3. Descending aorta (which is divided into thoracic and abd. portions) - formed from fusion of Right and Left dorsal aortae from T4 to L4

Describe the modification of saliva in the salivary ducts

1. Carbonic Anhydrase (C.A.) makes HCO3- and H+ 2. Na+ reabsorbed cell via uniport (apical) and via H+ antiport (apical) 3. Cl- reabsorbed via HCO3- antiport (apical) 4. K+ uses uniport to enter ECF (badolateral) and H+ antiport to enter lumen (apical) 5. Cl- exits into ECF via uniport (basolateral) 6. H+ exits via Na+ antiport (basolateral) * NO paracellular transport anymore * water does NOT cross to ECF- it stays in lumen (remember water did cross the salivary acinar cells) * The more reabsorption of ions takes place, the more hypotonic the saliva ** basolateral ECF surface goes to blood

What are the 4 parts of the stomach

1. Cardia - at level of T11 when supine (changes when standing) 2. Fundus - dilated part (gas or sometimes fluids) 3. Body - has two curvatures (greater and lesser) - ENS function lies along the greater curvature - this is where most action takes place, where most of the food is found 4. Pylorus - "gate keeper" that controls the outflow of chyme - pyrloric antrum: chamber (does grinding of food) - pyloric canal: outflow region (leads to pyloric sphincter- and once you pass this you are in the duodenum)

High Pressure Baroreceptor locations:

1. Carotid Sinus 2. Aortic Arch 3. Renal Afferent Arteriole (kidney) ------------- In baroreceptors the degree of stretch correlates with changes in BP - increased stretch indicates and increase in BP and an increase in baroreceptor discharge - decreased stretch indicates a decrease in BP associated with a decrease in baroreceptor discharge

Duodenum has dual arterial supply from

1. Celiac trunk: - Anterior and Posterior SUPERIOR pancreaticoduodenal arteries 2. From the Gastroduodenal artery which gives off the Supraduodenal artery 3. Superior Mesenteric Artery: - Anterior and Posterior INFERIOR pancreaticoduodenal arteries

Supernumerary Ribs "additional ribs"

1. Cervical Ribs - about 0.5-2% of population have a cervical rib - can be unilateral or bilateral - associated with THORACIC OUTLET SYNDROME: can result in the compression of neurovascular structures exiting or entering the Superior Thoracic Aperture - can lead to confusion of the vertebral levels in diagnostic images 2. Lumbar Ribs - AKA "the 13th ribs" <1% of population - can be unilateral or bilateral - RARELY associated with any clinical conditons

What are the 3 models of structure of the Liver Parenchyma that have been devised in order to relate the major functional activities of the liver to its structure?

1. Classic Hepatic Lobule (portal triad at periphery, central vein at center) - 6-sided - offers a basic understanding of the structure-function relationship - emphasizes the ENDOCRINE function of the hepatocytes as bloow flows pat them towards the central vein 2. Portal Lobule - Emphasizes the hepatocytes EXOCRINE function and the flow of bile from regions of the classic lobules towards the branch of the bile duct within the portal triad 3. Hepatic (Liver) Acinus - emphasizes the diff. oxygen and nutrient contents of blood at diff. distances along the sinusoids, with blood from each portal area supplying cells in two or more classic lobules - major activity in each hepatocyte is determined by its location along the oxygen/nutrient gradient ** Many pathological changes in the liver are BEST understood from the point of view of the liver acinus - More oxygenated blood at periphery (Zone I: portal triad) and more poor oxygenated blood near the central vein (Zone III) These 3 Zones are labeled: Periportal, Mid-Zonal, and Centrilobular CLINICAL: Zone 3 or Centrilobular Zone is MORE at risk for damage from hypoxic or ischemic heart failure due to it being ALREADY oxygen and nutrient deficient - Any toxins would mostly affect Zone 1 (periportal zone)

Describe 5 types of cells that are found in the epithelium of the small intestine (*remember Mucosa consists of 3 components: epithelium (which is simple columnar at this point), lamina propria, and muscularis mucosae

1. Columnar Absorptive Cell (AKA enterocytes) - darkest cells - have a striated (brush) border of microvilli for absorption - coeated with glycocalyx - decrease in frequency towards the large intestine 2. Goblet Cell - less numerous than enterocytes - in villus and base of villus "cryptal regions" - secrete mucus for protection - increase in frequency towards the large intestine *** the 3 below are also in the basal/cryptal region: 3. Enteroendocrine cell (EEC) (APUD) cells - pale staining - enter local circulation and modulate various activities of the GI tract - found within the crypts - D cells: secrete somatostatin (subclass VIP) - EC cells: secrete serotonin, motilin, and substance P - G cells: secrete gastrin - I cells: secrete CCK (cholecystokinin) - K cells: secrete GIP (gastric inhibitory peptide) - S cells: secrete secretin * these secreting cells can not be told a part by H&E you need a special immunohistochemical stain 4. Paneth Cell - located at the base of the crypts - produce lysozyme from its granules 5. Stem Cell - pleuripotential cells that give rise to the epithelial cells, paneth cells, and EEC * these are difficult to identify unless you see the mitotic figures

What are 4 smooth muscle contraction patterns found in the digestive system?

1. Contracted unless time to relax (sphincters such as the internal anal sphincter are normally closed (contracted) unless directed to relax - normally contracted smooth m. most commonly make up involunray sphincters (ex. pylorus)- these structures can sometimes be stimulated to RELAX (ex. with VIP or NO for the lower esophageal sphincter) but the default state is contraction, which results in closure of a section of gut tube 2. Blood vessels (ex. arterioles in duodenal wall) always partially contracted under ANS control & airways - this pattern leaves that muscle highly sensitive to slight variations in stimulation for graded changes in contractile state, and with it arterial blood pressure and venous return 3. Smooth m. wall relaxed until time to contract (gallbladder) *rememeber CCK does this kind of squezzing - normall relaxed smooth m. resembles that of most skeletal m., in that to get the muscle to contract signals to direct it to do so are sent from the control center to appropriate muscle- the smooth m. of the main part of esophagus is an ex, it is typically passive & quiescent in the abscence of any food within but when a bolus arrives it will vigorously contract if necessary to propel food or liquid towards the stomach 4. "Phasically active": much of the rest of the gut wall from the stomach to colon undergoes phases of contracted to relaxed "Now & Later" - ex. Uterus of a mother in labor, or in intestinal tract (undergoes cycles of contraction and relaxation, the duration and intensity of which can be carefully regulated with either nueral stimulation or hormones)

Drugs to Treat Acid-Peptic Diseases can be divided into:

1. Drugs Reducing Intragastric Acid A. Antacids - Aluminum hydroxide-Magnesium hydroxide - Calcium carbonate - Sodium bicarbonate B. H2-Receptor Antagonists - Cimetidine - Famotidine C. Proton Pump Inhibitors - Esomeprazole - Omeprazole 2. Mucosal Protective Agents - Bismuth Subalicylate - Misoprostol - Sucralfate

Prenatal circulation is different to the adult circulation as the fetus is obtaining oxygen from the mother via the placental circulation NOT via its lungs. There are 3 shut systems which are open prenatally and normally close post-natally in order to allow the majority of blood to bypass the liver and lungs. Theses 3 shunts are:

1. Ductus Venosus (shunts blood from umbilical vein to IVC) 2. Foramen Ovale (oval foramen) (shunts blood from right and left atrium, bypassing pulmonary circulation) 3. Ductus arteriosus (shunts blood from the pulmonary trunk to aorta, bypassing pulmonary circulation)

Postnatal circulation

1. Ductus venosus: there is closure of the lumen via contraction of muscular wall at birth to give the LIGAMENTUM VENOSUM 2. Foramen ovale (oval foramen): due to increases pressure in LA after birth it closes to give the FOSSA OVALIS 3. Ductus Arteriosus (normally immediately after bith in full term infant- closure of the lumen via contraction of muscular wall to give the LIGAMENTUM ARTERIOSUM)

At the surface of the anterior abd wall- curved lines that mark the lateral borders of the rectus abdominis muscles are referred to as

Linea Semilunaris - runs from costal cartilages to pubic tubercles "semilunaris"= crescent moon

What are 3 secretagogues for Parietal Cell HCl secretion?

1. ENS' ACh via M3 receptor and PLC second mesenger 2. Gastrin from G cells act on CCK2 via PLC secong messenger * within parietal cell, both ACh and gastrin activate PLC, producing IP3 and DAG ---> IP3-stimulated calcium release from ER * both of these above can also act on ECl cell with their receptors (M3 and CCK2) on parietal cells and receptors on adjacent Enterochromaffin-Like Cells (ECLs) where they stimulate production and secretion of histamine which acts in a different way via H2 receptor via Gs increasing AC, producing cAMP ---> PKA increased activation og the ATPase ------all these function to increase the activity of the H+/K+ ATPase------- Prostaglandins work to inhibit this process/keep it in check via Gi (inhibits too much histamine via blocking AC path. so that less cAMP is produced (ex. NSAIDS decrease prostaglandins- regulatory feedback gone- secrete too much acid: peptic ulcers) ------ In the end, the activity of the ATPase within the fully assembled tubulovesicles is the determining factor of the volume of gastric acid secreted into the pit lumen

Indirect measurements of cardiac output

1. Echodcardiography - estimates cardiac output and/or ejection fraction by measuring changes in ventricular dimension with each heart beat - also used to examine heart structures, valve area, jet velocity of blood, and pressure gradients (diagnose valve pathologies) ** alternatively, volume of blood leaving the aorta with each heart beat can be estimated using a pulse-doppler flow probe 2. Calculating CO- Fick Principle CO= VO2/ Ca- Cv basicallt: CO= O2 consumption/ Arterial O2- Venous O2 - VO2= the rate of O2 consumption per min using a spirometer (with the subject re-breathing air) and a CO2 absorber - Ca= oxygen content of blood per mL collected from a peripheral artery (ex. pulmonary vein, radial artery, aorta, brachial and femoral arteries) - Cv= oxygen content/mL of mixed venous blood (ex. pulmonary artery, RA, RV- this can only be done safely in hospital environment using a cardiac catheterization) ** can ONLY be used with oxygen consumption is NOT changing (at rest)

Describe some Antigen Sampling Pathways in mucosal immunity of the GI

1. Enterocyte pathway-> NO co-stimulatory signals (B7 negative)-> NO ACTIVATION (allows for tolerance of normal microbiota bc there is NO link with the inductive site so it is UNABLE to deliver antigen and lacks the capacity to pick up antigen and show it to the inductive site) 2. M cell (microfold cell) pathway--> transcytosis --> antigen delivery to APC --> activation (in GALT, peyers patches, appendix, colon follicles) 3. Dendritic Cell Pathway--> professional APC --> activation (dendrites pick up the antigen and produce and immune response- can occur in the mesenteric lymph nodes)

Thoracic wall Musculature includes

1. Extrinsic Muscles - Stabilizes and moves the pectoral girdle, upper limbs, and neck (ex. Pectorals, Rhomboids, Scalene Muscles) * review superficial and deep back lecture 2. Intrinsic Muscles (Intercostal Muscles--> between the ribs) These include 3 groups of muscles 1. External intercostal muscles 2. Internal intercostal muscles 3. Innermost intercostal muscles *** Neurvascular bundle runs between the internal and innermost intercostal muscles ** Intercostal muscles are served by the corresponding intercostal nerves and vessels

Edema is excess fluid in the interstitial space- what are 2 types

1. Exudate: is interstitial fluid containing proteins as a consequence of altered capillary permeability (ex. insect bites) 2. Transudate: interstitial fluid WITHOUT proteins (ultrafiltrate) a. swollen ankles due to peripheral edema (ex. consequence of RVHF ) b. pulmonary congestion (ex. a consequence of LVHF) c. Impaired lympathic drainage (unilateral peripheral edema)- may be induced following surgical disruption of the lymphatic system

What are the 3 main parts of the Gallbladder?

1. Fundus: the wide, round end 2. Body: the main portion that is in contact with the FIRST part of the duodenum and the visceral surface of the liver 3. Neck: Narrow s-shaped bend. The mucosa begins to twirl into a spiral fold which acts like a valve in the cystic duct- sometimes called the "Spiral Valves of Heister"

At the surface of the anterior abd wall- the white tendinous line that forms the midline is the

Linea alba - runs from the xiphoid process to pubic symphysis - separates the R and L rectus abdmoinis muscles * devoid of vasculature, nerves or muscles so following abdominal trauma surgeon can access abd. cavity quickly and safely "alba"= white

Which lipase acts in the mouth, esophagus and stomach?

Lingual lipase - secreted by salivary gland

Sublingual Gland

Lingual refers to the tongue - paired gland - surrounds the terminal portions of the submandibular ducts - secretions empty into the floor of the mount by 10-20 short ductulres * this one activates when you are nervous- thick gooey mucus rich secretion ** this is a MAJOR salivary gland * remember that all major glands are all paired- so there are 3 pairs, meaning 6 glands

What are 3 Major classes of Intestinal Motility Reflexes?

1. Gastric-to-(intestine or colon) Fx: proximal-to-distal- stimulates distal region to empty it, "make room" for food curently in the stomach ("grandpa needs to go to bathroom shortly after eating") Ex. Gastrocolic reflex 2. (intestine-or-colon) to gastric Fx: Distal-to-proximal- relaxes stomach to reduce gastric emptying, give more time for processing of materials already in the intestine (activates sensory NS tells them ileum is full- stop contraction using more VIP) Ex. Ileo-gastric reflex 3. Reflex within same organ or adjacent organ Fx: coordinate activity within that region- can mediate segmentation contractions Ex. Recto-sphincterix reflex: when rectum is stretched it relaxes internal anal sphincter which allows movement into the anal canal - Required for defecation ----- * Only when the regions are directly adjacent to one another might they be mediated by the ENS alone by short-loop reflexes- this is not typical * In majority of cases (ex. gastrocolic reflex) the distances are too great and these reflexes will go through the spinal cord and/or brainstem just like other autonomic reflexes * slowing the proximal regions gives the distal regions time to process material before theyre swept past the absorption transporters. Speeding the distal areas ultimately leaves room for material in the proximal region to enter the next distal region for digestion and/or absorption

What are the 4 portions of the pancreas?

1. Head: Sits in the "c-shaped" curve of the duodenum (formed by 1st,2nd,2rd portion of duodenum) and lies to the RIGHT of the superior mesenteric artery --> the uncinate process lies POSTERIOR to the superior mesenteric artery (which supplies midgut structures) 2. Neck: constricted part that is between the head and body and lies DIRECTLY behind the PYLORUS of the stomach 3. Body: lies to the LEFT of the superior mesenteric artery and passes ANTERIOR to the abdominal aorta 4. Tail: is the ONLY intraperitoneal part as it is closely related to the hilum of the spleen and lies WITHIN the splenorenal ligament

The Clinical Approach to every patient is:

1. History 2. Physical Exam 3. Formulate a Differential Diagnosis 4. Investigations and imaging 5. Management plan (ex. treatment) For acute patients revert back to the ABCs (Airway, Breathing, Circulation) and rescucitate in order to stabilize before proceeding to deal with the chief complaint in order above

The muscularis externa (ME) of the stomach has 3 unique layers which are

1. Inner Oblique (O)** unique to stomach** 2. Middle circular (C) 3. Outer longitudinal (L)

What 4 things contribute to Mucosal Immunity in the Intestine

1. Intestinal mucus production - lubrication - entrapment of bacteria - expulsion of parasites 2. Intestinal Epithelium - physical barrier - chemical barrier: antimicrobial secretion, mucosal antibody (IgA mainly)- decreased IgA may lead to infection (ex. Giardia Lamblia) 3. Peristalsis - expulsion of pathogens and waste products - required for normal functioning of system * intestinal stasis --> disease 4. Intestinal Microbiota **** (this is critical!) * NOTE: there are MORE bacterial cells in the intestinal tract than almost any where else in the body Fxs of intestinal microbiota are: - competitive inhibition of pathogens - required for normal immune development (note a baby with A blood type does not develop Anti B until it is exposed to bacteria, antibodies are formed from contact with bacteria- "dirt is good") - vitamin synthesis (ex. Vit K important for blood clotting) - deconjugation of bile salts - production of antimicrobials

Common causes of L heart failure include:

1. MI 2. Uncontrolled hypertension 3. valve pathologies Sxs and symptoms: - S3 heart sound - pulmonary edema on chest x-ray and auscultated - left axis deviaition (LAD), Afib, and LA enlargement can be seen on ECG

Abdonmial structures associated or derived from the periotoneum

1. Mesentery 2. Omenta (greater and lesser) 3. Peritoneal ligaments 4. Peritoneal recesses 5. Peritoneal Fossae

What are the 5 general patterns of Digestion and Absorption?

1. Monomer, NO digestion required (ex. glucose) 2. Digestion in LUMEN, into monomers (ex. proteins) 3. Digestions in LUMEN into oligomers, further digestion at BRUSH BORDER into monomers (ex. sucrose) 4. Dimers and trimers absorbed into enterocyte digested into monomers INSIDE the cell (ex. peptide) 5. Digestion into monomers in lumen, absorption into enterocytes--> repacked into larger molecules before exiting enterocytes (ex. TAG) -------- so in simpler terms 1. nothing 2. lumenal digestion 3. lumen + brush border 4. need to finish digestion inside the cell 5. digest outside- repackage inside

4 layers of the esophagus proceeding from the inside (i.e. abluminally from the lumen)

1. Mucosa (external) 2. Submucosa (has glands) 3. Muscularis externa (has layers for squeezing) 4. Adventitia/Serosa (deepst layer)- adventitia in esophagus bc its a GI organ that doesnt move around as much-stays in place --- * note areas that move more are lined with serosa * these 4 layers listed are in GI tube - the lumen which is surrounded by mucosa is the outside of the body- anything found here is outside of the body it is not part of the body yet

The wall of the Gallbladder is made up of 3 layers (unlike the usual 4 that we are used to seeing)

1. Mucosa: - simple columnar epithelium overlying lamina propria - these is NO muscularis mucosae seperating it from Submucosa bc the Gallbladder does NOT have a submucosa 2. Muscularis: - muscle fibers oriented in all direction to facilitate emptying 3. Serosa or Adventitia - Serosa: when the gallbladder has NO contact with the liver - Advenititia: when gallbladder is in DIRECT contact with the liver

Describe the Secretion of Primary Saliva from the Salivary Acinar Cells

1. Na+, Cl-, K+ enter cell via symport (from basolateral side ECF) 2. CO2 + H2O with Carbonic Anhydrase (C.A) makes HCO3- and H+ 3. HCO3- and Cl- secreted via symport to enter acinar lumen 4. K+ secreted via uniport (apical-lumen) and leaves via uniport (basolateral) 5. H+ leaves via Na+ antiport (basolateral ECF) 6. Na+ and H2O follow Cl- into lumen by paracellular route (following its electrical gradient for Na+, and its osmotic gradient for H2O)- BOTH req a somewhat "leaky" junction between epithelial cells ** Cl- movement into cell creates conc. gradient- Cl- and HCO3- will move through channel into lumen 7. Amylase and other enzymes enter lumen by exocytosis

Describe the mechanism of swallowing

1. Oral phase (gets things into pharynx in first place) - tongue moves bolus into place (tongue thrust up and back) - nasopharynx closes - food forced towards pharynx - larynx begins to elevate - touch receptors initiate swallowing reflex 2. Pharyngeal Stage (close airway to get bolus through) - airway closes as larynx pulled up against epiglottis - tongue forces bolus into pharynx - UES relaxes (opens) - Pharynx contracts, forces bolus through the UES (bolus enters esophagous) 3. Esophageal peristalsis wave initiated - Bolus begins movement toward stomach- both circular and longitudinal muscle is involved - Pharynx, UES, etc. return to base settings ** note that the events of swallowing overlap one another so the transition point between the phases reflects when the bolus passes into and then out of the pharynx

What are 3 modes of Chloride Absoprtion by the intestine?

1. Passive Reabsorption - paracellular - following sodium electrochemically - greatest in jejunum, ileum, distal colon * associated with nutrient absorption and fine control of plasma volume - voltage-dependent passive absorption, which occurs in every location which sodium is absorbed is chloride ions following the more actively-absorbed sodium ions either across the cell (transcellular) or between cells (paracellular). Classic examples are following sodium and glucose in carbohydrate absorption, and sodium and amino acids. 2. Chloride-bicarbonate exchanger - secondary active transport (for hydrogen, the byproduct of carbonic anhydrase) - greatest in proximal colon, ileum, and distal colon: particularly in locations where bacteria are producing excess acid, to better neutralize that osmotic agent and also bring chloride and water into the blood - it is most active where there is both a LOT of water and a LOT of colonic bacteria, the proximal (ascending) colon * associated with bicarbonate secretion (crypt cells) 3. Parallel Na-H and Cl-HCO3 exchangers - brings in both soidum and chloride into the cell for absorption and both hydrogen and bicarbonate out for processing by carbonic anhydrase - in lumen the secreted bicarbonate and hydrogen are convereted back into CO2 and water - greatest in ileum and proximal colon * associated with mass absorption of NaCl and water (either way water tends to follow the sodium and chloride into the blood) *** sodium, chloride, and water absorption are all tied together

What are two modes of Potassium absorption?

1. Passive absorption - paracellular*: this is not so much diffusion as "bulk processing", in which the potassium ions are carried along with water from the lumen to the blood, like a stick carried down a river - carried with water in bulk processing (solvent drag) - greatest in jejunum and ileum 2. Active absoprtion - involves exchange with hydrogen at surface of epithelial cells - ONLY occurs in most distal colon as part of the fine control of correcting a hypokalemia in the plasma - most typically with dietary K+ depletion (remember that K+ must be regulated well in order to not have arrhythmias, if someone is short on potassium in the plasma the cardiac arrhythmias might occur) NOTE: the distal colon can either secrete or absorb potassium depending on body needs for potassium * Potassium absorption is critical for maintenance of homeostasis, but is does NOT have many active transport mechanisms * why through any potassium away in the feces?

Prior to commencing interpretation of ANY image always check the following details in the following order:

1. Patient details: name, date of birth and patient identification number 2. Date and time film was taken 3. Previous imaging: any previous imaging taken (same modality) useful comparison

Venules have 2 types

1. Post capillary venules - smallest venules (diameter of 10-50micrometers) - tunica intima consists of endothelium and pericytes - no tunica media or tunica adventitia - site of WBC migration- WBCs adhere to endothelium and leave the circulation at sites of infection of tissue damage 2. Muscular venules - larger (diameter of 50-100 micrmeters) - Tunica intima: consists of endothelium and NO pericytes - Tunica media: consists of 1-2 layers of smooth muscle - Tunica adventitia consists of CT, some elastic fibers and is thicker than tunica media

What are the two stages of Salivary Secretion

1. Primary Salivary Secretion - produced by salivary acinar cells - found in acinar lumen - ions similar to plasma though not identical (Cl- enters into lumen, and absorb Na+ after, H2O follows both) - contains some proteins 2. Ductal Processing - sodium and chloride reabsorbed from primary saliva - water not reabsorbed so final saliva is hypotonia - may secrete some potassium and bicarbonate as needed - proteins unaffected in ducts Note: - salivary amylase is secreted by exocytosis from salivary acinar cells - since H2O is NOT reabsorbed in salivary ducts, as ions are absorbed the conc. of ions/L decreases in final product, making it hypotonis - bicarbonate concentrations rise in the final product, making the final secreted saliva more alkaline than plasma

What are 3 function the motor activity of the GI tract performs?

1. Produces segmental contractions (move tube back/firth so that what is in the middle of the gut can wind up on the wall to be absorbed) that are associated with nonpropulsive movement of the luminal contents - results in CHURNING that enhances digestion and absorption of dietary nutrients 2. GI motor activity produces peristalsis, a progressive wave of relaxation followed by contraction - results in PROPULSION, or the propagated movement of food and its digestive products in a caudal direction (makes sure material form segmental contraction makes its way down colon) 3. Promote relaxation- allows some hollow organs (especially stomach and colon) to hold the luminal content - exerts a RESERVOIR FUNCTION - sphincters support this reservoir function by separating organs of the GI tract * VIP (a relaxing NT): relaxes colon to move fluid from SI into colon as reservoir- this is supported by sphincters- to prevent fluid from flowing back into the SI

It is essential to convey blood around the embryonic body- therefore the primitive heart receives 3 paired vessels into the inflow portion which are:

1. R/L Vitelline veins (deoxygenated blood from yolk sac) 2. R/L Cardinal veins (deoxygendated blood from body of embryo) 3. R/L Umbilical veins (oxygenated blood from the placenta) *** these are the INFLOW portion ----------------- Primitive heart OUTFLOW portion: - Truncus arteriosus (TA)- (which will be partitioned into aorta and pulmonary trunk) it connects to the aortic arch arteries **

What are the 4 functions of the Large intestine (colon) and the role of motility in each one?

1. Reservoir Function: store colonic contents - most storage in distal (descending and recosigmoid) portion of colon) 2. Move its contents from cecum to rectum and then eliminate its contents via defacation through the anus 3. Absorb large quantities of fluids and electrolytes to convert the liquid content of ileocecal material to a solid or semisolid stool (greatest quantitiy absorbed in proximal (ascending and transverse) colon 4. Absorb those small-chain fatty acids produced by bacterial fermentation of dietary carbohydrates by colonic microflora (transverse and descending colon) * eliminatin of stored feces through the rectum

3 functions of Gastric Motility:

1. Reservoir creation: (like in professional eaters) - to receive ingested food and hold it for later processing - stomach smooth m. relaxes to reduce pressure and make room - occurs mostly in gastric fundus 2. Churning/Motility - facilitates mechanical and chemical digestion - occurs mostly in gastric antrum and body (not so much in fundus) - waves of contractions (3-4/min) force food from the gastric body into the antrum and back 3. Gastric emptying - small particles are forced into the duodenum past the pylorus - antrum contraction provides the pressure, duodenum the resistance - pylorus, antrum, and proximal part of the duodenum work as a single unit to coordinate the whole process * helps to get food small enough bc big chunks cant pass trhough pylorus or get to duodenum- bicarbonate helps to digest food at this point

4 Branches of the Right Coronary Artery

1. SA nodal branch (ant) 2. Right marginal branch (ant) 3. AV nodal branch (post) 4. Posterior interventricular (post- between R & L ventricle)

Steps in Improvement of a Quality Gap (using an example)

1. Set an Aim - How good is the improvement? "100% beta blockers prescribed will decrease mortality" - For whom? to improve system and pt - By when? definitive timeline *** Must be: bold, realistic, clear, concise, measurable, meaningful Ex of a good Aim statement: - Decrease rate of hospital-acquired pneumonia for pts in the ICU from 23 infections/1,000 catheter days to less than 5 infections/1000 catheter days by May 1 2. Estabolish Measures - Outcome measures: "where are we going" - Process meadures " what are we doing"

What are 3 mechanism for the absorption into the enterocyte of digested lipids?

1. Simple diffusion 2. Incorporation into the enterocytes cell membrane 3. Carrier-mediated transport - at least 3 carriers are known - particularly important for short and medium chain fatty acids, which are more water soluble ** these lipids move to more neutral environment but to one that is overall more acidic than the outside (pH 8 in SI --> pH 6.9 at entry of enterocyte)

Mechanisms to reduce venous pooling

1. Skeletal muscle pump: - skeletal m. contractions force venous blood toward the heart - increases venous return - reduces venous volume and pressure - venous valves prevent backflow of blood 2. Thoracic muscle pump: "aka respiratory pump" - changes in intrathoracic pressure upon inspiration affect CVP and venous return Deep inspiration --> decreased intrathoracic pressure --> decreased RAP --> increased drivign pressure from LE to central venous space --> increases venous return

List the coverings of the Scrotum:

1. Skin 2. Dartos muscle and Superficial Fascia - Dartos muscle is smooth and receives autonomic innervation (GVE) - works in conjunction with the striated cremasteric muscle 3. External Spermatic Fascia - derived from external oblique m./fascia 4. Cremaster fascia and muscle - derived from internal oblique m./fascia 5. Internal Spermatic Fascia - derived from transversalis fascia

What are the coverings of the testes?

1. Skin 2. Tunica Dartos (aka Dartos m./fascia): derived from scarpas fascia 3. External spermatic fascia: derived from external oblique m/fascia 4. Cremaster muscle and fascia: derived from internal oblique muscle/fascia 5. Internal spermatic fascia: derived from transversalis fascia 6. Tunica Vaginalis (2 layers separated by peritoneal cavity) - Parietal Layer - Visceral Layer- is cont. with the tunica albuginea "white layer" (remember visceral layer is associated with the organ) * there is also a cavity of the tunica vaginalis

Layers of the Thoracic Wall (superficial to deep)

1. Skin (superficial) 2. Superficial fascia 3. Intercostal Muscles - external mm - internal mm - innermost mm 4. Endothoracic Fascia 5. Parietal Pleura 6. Pleural Space (most deep) ** NOTE: Visceral pleura is NOT part of thoracic wall layers

What are 3 uses for water in digestion?

1. Solubilization - breaks food particles into smaller pieces by dissolving water-soluble components - emulsifies hydrophobic component - water is needed to hydrate and solubilized the monomers as they are made 2. Digestion - one molecule of water is used for every bond broken 3. Absorption - macronutrients cannot be absorbed in a solid state, they must be dissolved in water

Describe the process of peristalsis (moving things from A --> B in caudal direction)

1. Stretch in one section is sensed (chemoreceptors sometimes also work) (increases resistance, increased pressure) 2. Oral to bolus - the circular smooth muscle conracts - longitudinal smooth muscle relaxes - pressure increases 3. Anal to bolus - circular smooth muscle relaxes - longitudinal smooth muscle contracts - pressure decreases, resistance decreases 4. Bolus moves in anal direction from propulsive to receiving segment * sensing the presence of a bolus and coordinating its movement from an oral --> anal direction is the function of the Enteric Nervous System (ENS) ** you squeeze circular smooth m. oral to the bolus and relax circular smooth m. caudal to the bolus- the pressure gradient should let bolus move

The lymphatic around the celiac trunk (foregut) drain by two routes which are:

1. Superficial (associated with the BARE area (where liver is NOT covered by visceral peritoneum)--> Phrenic or Posterior Mediastinal l.n. 2. Deep (associated with the porta hepatis/anterior visceral surface) --> Hepatic or Celiac l.n. --------- Innervation to this area: - Parasympathetic --> Vagus (CNX) - Sympathetic --> Hepatic Nerve Plexus (part of the celiac plexus) *** The exact role of the hepatic nervous supply is largely unknown although it does control vasoconstriction

What are two pathways of intestinal calcium absorption?

1. Transcellular Ca2+ absorption (most absorption that goes into the cell- this is highly regulated) 2. Paracellular Ca2+ absorption (minor path- through tight junctions that connect the cells to eachother) ------- Like other divalent ions, calciums usual absorption is limited not by the quantity in the diet but by the number and activation state of transporters at the absorptive cells - once inside the cell- much of the calcium is temporarily held in place by a protein called calbindin before it is finally transported across the basolateral membrane by either primary active transport (calcium-hydrogen antiport pump), or secondary active transport like that seen in the heart (sodium-calcium antiport with a sodium-potassium pump)

The 4 abdominal quadrants are divided according to two lines which are

1. Transumbilical plane: horizontal line through the umbilicus- divides into upper and lower quadrants 2. Median plane: vertical line through the midline- divides into right and left quadrants ---- 4 quadrants are: RUQ, LUQ, RLQ and LLQ

With differential growth of the heart tube 5 dilations become apparent which are

1. Truncus arteriosus (most caudal) 2. Bulbus cordis 3. Ventricle 4. Atrium 5. Sinus venossu (R and L horns) ** these develop into the adult structures of the heart * NOTICE that ventricle sits ontop of atrium- this changes after development

What are the four steps of processing for secretion in hepatocytes?

1. Uptake of material from (basolateral) sinusoidal blood - secondary active transport of bile acids/salts 2. Transport within the cell 3. Chemical modification of materials - ex. conjugation (add extra AA) of bile acids from unconjugated bile acids, or - production of new bile acids from scratch 4. Secretion of materials into the bile through canalicular (apical) membranes - ex. primary active transport of bile salts - NaCl, bicarbonate, other ions, and water - Other miscellaneous waste products ----------- NOTE: there is both passive permeation and active secretion into the apical canaliculis Passive permeation (either diffusion or bulk flow through the tight junctions) of: - water - glucose - calcium - glutathione - AAs - urea Active secretion (through apical membrane) of: - bile acids - phosphatidylcholine - conjugated bilirubin - xenobiotics

VLDL life cycle

1. VLDL is assembled in constantly in the liver in both fed and fasting state and secreted- nascent VLDL has full length apoB-100 - TAG is also synthesized in the liver from FFA uptake, chylomicrone remnant uptake and FA synthesis - Cholesterol is also synthesized and esterified in the liver or from uptake 2. ApoC-II and ApoE are transferred from HDL to VLDL - VLDL delivers TAG to peripheral tissues: Adipose and muscle 3. TAG is removed by LPL (LPL degrades the TAG to FFAs) in the capillary bed, makes VLDL into --> IDL when depleted of TAG ** LPL activity is regulated just as it was described for chylomicrons ** IDL interacts with HDL and becomes LDL ** IDL can be taken up by the liver through apoE receptors (as for chylomicron remnants) 4. Transfer of Apo C-II and Apo-E back to HDL ** residual TAG is transfered to HDL ** cholesterol esters are transferred from HDL--> IDL The particle with only apo B-100 is now LDL 5. LDL delivers cholesterol and cholesterol esters to peripheral tissues (muscle)(uptake is via the LDL receptor, which recognizes B-100 and NOT B-48) and can also go back to the liver (70%)(LDL receptor also recognizes apoE for uptake of chylomicron remnants and IDL in the liver Clinical Correlate: Fatty liver disease: accumulation of TAG in the liver due to imbalance of VLDL production and TAG synthesis Abetalipoproteinemia: lack of B-48 and B-100 production --> Affects both chylomicrons and VLDL production

Locations of Low pressure baroreceptors

1. Vena cava (superior and inferior) 2. Right atrium 3. Pulmonary artery *** these are the cardiopulmonary baroreceptors which monitor the fullness of the circulation, i.e. blood volume

The structure of the small intestine is complex with folding into

1. Villi 2. Microvilli (AKA brush border) * these both increase surface area for absorption and digestion Several enzymes are attached to the enterocytes of the villi, primarily on the microvilli: - enteropeptidase/enterokinase - aminopeptidase N - dipeptidase - maltase - isomaltase - sucrase AND a number of transports are located in close proximity to the above enzymes: - amino acid transporters - di- and tri-peptide transporters - glucose transporter - ribose transporter - fructose transporter - galactose transporter - fatty acid transporter NOTE: microorganisms (microbiota) form a protective layer in the mucous that coats the brush border Clinical: Giardia destroys microvilli which will decrease absorption in an infection

3 sites where the esophagus is prone to constriction

1. Where esophagus is crossed by the aortic arch (blood leaving the L ventricle enters into the ascending aorta and then arch of the aorta) 2. Where esophagus is compressed by the L main bronchus (trachea bifurcates/divides into a R and L main bronchus) 3. Level of diaphragmatic esophageal hiatus (vertebral level T10)

4 phases of the valsalva manuever

1. arterial BP increases initially as thoracic aorta is compressed by high intrathoracic pressure. HR declines due to decreased activation of baroreceptors 2. arterial pule pressure and MAP beging to decline bc the high intrathoracic pressure reduces VR and thus reduces SV and PP. Ove the next 5-10 sec a reflex increase in sympathetic outflow causes an increase in HR and peripheral vasoconstriction which halts the ongoing frop in MAP 3: on terminating the valsava maneuver, intrathoracic pressure returns to normal and the thoracic aorta is decompressed- arterial BP falls transiently giving a reflex rise in HR 4. puple pressre and MAP increase steeply bc blood surges into the thorax increasing venous return, ventricular filling and increasing EDV- via starlings law, this increased CO, MAP, and pulse pressure- this then activates the baroreceptor reflex leading to a transient reflex bradycardia ( this sudden bradycardia is used as a clinical test for the competence of the baroreflex) *** an increase in aortic pressure leads to a decrease in baroreceptor firing

Cardiac cycle during exercise

1. cardiac period is shortened to 300-350 ms (ex. 333ms at 180 bpm) 2. duration of systole is reduced 3. slow filling phase (diastasis) is reduced significantly 4. atrial contraction helps maintain EDV and SV 5. ventricular and aortic systolic pressure increase 6. CO is a balance between SV and HR *** at very high heart rates the systolic and diastolic phases shorten significantly and stroke volume will be decreased due to reduced ventricular filling time

Physiological causes of edema

1. decreased arteriolar resistance--> increases capillary hydrostatic pressure--> increases filtration --> edema 2. increased venous resistance --> increased capillary hydrostatic pressure --> increases filtration--> edema 3. decreased plasma proteins --> decreases capillary colloid osmotic pressure --> decreases reabsorption --> edema 4. decrease lymph drainage --> increased interstitial capillary pressure --> edema

Measurements of intra-esophageal pressure suggests two defects in patients with achalasia

1. failure of the LES to relax and 2. impaired peristalsis in the distal esophagus (i.e. the portion that consists of smooth muscle) - peristalsis may still be intact in the proximal third of the esophagus, which consists of striated muscle, if it is not too dilated with food backed up from the more distal regions * long-term adaptation of the esophagus to masses within the lumen is called megaesophagus- it is analogous to the megacolon sometimes seen with long-term motility loss in the colon

Normal circulatory funsion depends on 3 components. When one or more of these circulatory components fail shock results.

1. inadequate blood volume (hemorrhage) 2. inadequate cardiac function (decreased CO) 3. inappropriate vascular tone (blood vessels)

In vascular function curve 3 parameted will increase venous return and CO

1. increase in blood volume 2. decrease in venous compliance (increased venous tone or constrciton) 3. decreased arteriole resistance

Parameters affecting hemodynamics

1. individual blood vessel diameter 2. mean blood flow velocity 3. total cross-sectional area 4. Blood volume distribution 5. total peripher resistance (TPR) 6. mean blood pressure

What steps are involved in the digestion of carbohydrates

1. luminal digestion by amylases (salivary & pancreatic) - ingested starch and glycogen is broken into alpha-dextrins, maltose, isomaltose etc.) - brush border digestive enzymes glucoamylase (maltase) and sucrase/isomaltase can break these up into glucose for brush border absorption - also sucrase/isomaltase can break sucrose into glucose and fructose for brush border absorption - and lactase can break lastose into glucose and galactose for brush border absorption *** NOTE that ingested cellulose has no further digestion or absorption- insoluble "fiber" ** Enterocytes absorb only the 3 monosaccharides (glucose, fructose, galactose)

two mechanisms for local (or intrinsic) control of blood flow

1. metabolic control of blood flow (originates from the surrounding tissue) - metabolites regulate blood flow - paracrine agents regulate blood flow (produced locally, released locally and act locally) 2. myogenic control of bloow flow (originates from WITHIN the vessel) - myogenic reflexes regulate blood flow - endothelial products (nitric oxide) regulate blood flow

Aerobic conditioning

1. reduces resting HR - due primarily to an increase in resting vagal tone 2. enlargemnet of ventricles (physiological hypertrophy) - SV at rest will be greater than in a sedentary individual 3. Stimulates angiogenesis in exercising skeletal and heart muscles - increased cardiac and skeletal muscle vascularization *** detraining will reduce these adaptations

What are some protective mechanisms within the esophagus

1. thick stratified squamous epithelium 2. scattered lymphatic tissue (mainly B cells) - antibodies constantly present in lamina propria and submucosa, these are the first line of defense against viral invasion across the epithelium

Small intestinal secretions are quantitatively very important, at apprx.

1000mL/day (1L/day) directly from instestin itself - contains mucus - aqueous component whose ion composition is essentially the same as plasma (no ducts= no reprocessing) - some capability for secretion of bicarbonate * values of secretion have no one definitive guide bc the values differ based on diet - acid-buffering food will increase gastric juice secretion - fatty foods will increase bile secretion Some relative secretion values: - Saliva (1500mL/day) - Gastric secretions (2500mL/day) - Bile (500mL/day) - Pancreatic juices (1500 mL/day) - Intestinal secretions (1000mL/day) -- Small intestine absorbs 7000mL/day Colon absorbs 1900mL/day

For a gain of 1lb a year, only about a

11-12 Cal daily excess of consumption is required - this is less than a percent of most diets - body on a whoel does a good joib of balancing intake and expenditure

What vertebral level are the 1st-4th parts of the duodenum found

1st: L1 2nd: L2 3rd: L3 4th: ascends back up to L2

Transit time through the intestine is

2-3 days - at such a speed, reaching the hardest stools possible will not happen - in such circumstans, waste material goes from fully liquid to the begining of clumps in the ascending colon - generates softer climps by end of transvers colon - has relatively soft but solid stools within the sigmoid colon (it is here that ingested fiber plays its most important part as the osmotic nature of cellulose will usually keep enough fluid within the wastes that it does not reach the potentially dangerous super-solid state that can lead to sever constipation and possible diverticulitis) - in addition, if motility is severely reduced then a pathological state can occur in which feces begin to become semisolid to solid in the transverse colon, resulting in severe constipation EXCEPTION: reflex such as the gastro-colic reflex occur when there is food in the stomach, but from the point of view of the colon, thats just another version of extrinsic modulation of the normal intrinsic control within the colons ENS - this is mediate via ICC cells there that influence slow wave activity in the smooth muscle proper

The esophagus is a

25cm long fibromuscular tube extending from the pharynx (C6 level) to the stomach (T11 level) - it lies posterior to the trachea and the heart and passes through the mediastinum and then through an opening in the diaphragm (at vertebral level T10), in its descent from thoracic to the abd cavity * note as passes through diaphragm its name changes from thoracic portion of esophagus to abd portion of esophagus

What are the 2nd and third (last) segment of the small intestienes

2nd part of SI= jejunum (the duodenum feeds into the jejunum) 3rd (last) segment of SI= ileum

Which rib articulates with the sternum at the sternal angle (of Louis)?

2nd rib

Cardiovascular system starts to develop in week

3 The heart precursor cells sit within the primary cardiogenic field: a horse-shoe shaped zone of splanchnic mesoderm (from subdivision of lateral plate mesoderm) cranial to developing neural tube - The cells split into 2 groups (R and L) to forma 2 endocardial lined tubes

Transcapillary Fluid Exchange

4 Starling Forces determine net movement of fluid across a capillary wall: Brain- non-porous capillaries, Liver: very porous capillaries Forces moving fluid OUT of capillary: 1. Capillary hydrostatic pressure, Pc 2. Interstitial colloid osmotic pressure, piI Forces moving fluid INTO a capillary: 3. Interstitial hydrostatic pressure, PI 4. Capillary colloid osmotic pressure; piC **NOTE interstitial pressure are usually insig. in a healthy person

Peritoneal Folds include

5 raised folds that provide protection to underlying structures Median Umbilical fold (x1) - midline - under this fold lies the median umbilical ligmanet - remnant of the embryological urachus - travels from the apex of the urinary bladder to the umbilicus Medial Umbilical Folds (x2) - paired on either side (lateral) of the midline - under these folds lie the medial umbilical ligaments - remnant of the embryological part of the umbilical arteries - blood traveled from the internal iliac arteries of the fetus back to the placenta Lateral Umbilical Folds (x2): - paired on either side (lateral) of the medial umbilical folds - under these folds lie the inferior epigastric vessels - inferior epigastric artery branches directly from the external iliac artery - inferior epigastric vein typically drains into the external iliac vein

The blood pressure threshold for eliciting carotid sinus nerve impulses is about

50-60mmHg, and a maximal sustained firing is reached around 200 mmHg ** The carotid sinus baroreceptors also have sensitivity to the rate of change in pulse pressure- during systolic rising phase where the rate of change of BP and therefore stretch of the arterial wall is most rapid, firing frequency is enhanced compared to the same pressure achieved during the declining phase of the pressure wave ** so during systolic rising phase the firing frequency increases

Ideal site for Chest tube/Chest drain

5th-6th intercostal space along the midaxillary line within the "safe traingle" - lateral edge of pectoralis major - axilla - anterior edge of latissimus dorsi - 5th intercostal space

During Thoracocentesis, inserting the needle into ____ during expiration will avoid the inferior border of the lung

8th-9th intercostal space at the midaxillary line

The 4 abdominal quadrants can be divided into __ abdominal regions

9 regions: 1. Right Hypochondriac 2. Left Hypochondriac 3. Right lumbar 4. Left lumbar 5. Right inguinal/ Iliac 6. Left inguinal/ Iliac region 7. Epigastric region 8. Umbilical region 9. Hypogastric region

How many kcal/g can you get out of carb, protein, fat, and alcohol

9447 Fat- 9kcal/ g Protein- 4kcal/g Carb- 4 kcal/g Alcohol- 7kcal/g ** fat is the most energy dense - the bulk of our diet 45-65% is required from carbs - 20-35% of energy is from fat: from essential fatty acids - 10-35% is from protein ** fiber does not contribute to overall caloric intake Nutrients in the diet include: Macronutrients: carb, proteins, fats Vitamins Minerals Water

In the absence of Intrinsic Factor (IF)

99% of Vitamin B12 is digested, resulting in Pernicious Anemia Usually: - Cobalamin (Vit B12) is req. for proper blood synthesis - Intrinsic factor (secreted by parietal cells) protects this peptide from digestion - Once past the digestive enzymes int he terminal ileum the complexes are absorbed - VitB12 enters portal blood, intrinsic factor is degraded BUT - is IF is NOT secreted for some reason- this absorption process involving endocytosis of cobalamin- IF complexes cannot occur- this could be secondary to loss of secretory capacity (gastric atrophy) following gastritis * since cobalamin (vit B12) is a regular protein- if left unprotected it will be digested and its AA absorbed just like any other ingested protein ** absence of cobalamin in blood will eventually result in lack of maturation of erythrocytes and development of pernicious anemia ***** one of the most common reasons for insufficient intrinsic factor secretion is any condition that reduces hydrochloric acid secretion in the stomach- because parietal cells secrete both HCl and intrinsic factor (one example of this is loss of oxyntic glands secondary to gastritis, leading to achlorhydria)

Simple Sugars and Disaccharides (dietary carbs) should be limited to

<10% of calories bc they are empty calories (just added to food for flavor) - digested rapidly (high GI) - will be more limited in future recommendations) Ex. High fructose corn syrup - is mostly glucose - chemical conversion used to convert glucose --> fructose (sweeter) - mixed with corn syrip to form a 50-50 mixture - in principle, not much diff. from sucrose * sucrose and high fructose corn syrup (HFCS) are processed foods- there is not much different dietarily between them - BOTH are simple sugars and when added to foods add no other nutritional benefit in terms of vitamins and minerals

Pancreatic (ADENO)Carcinoma

<40% rare, 70-80yr over 80% of cases- this is the 3rd leading cause of cancer deaths in the USA Risk factors: - smoking (25%), obesity, diabetes, genetic factors, diet (red meat) Genetics: -KRAS oncogene activation (90%), p16 (CDKN2A) tumor supprssor gene inactivation (95%), SMAD4 tumor suppressor gene inactivation (55%) - TP53 tumor suppressor gene inactivation (50-70%) - Precursor leasion (Pancreatic intra-epithelial neoplasia (PanIN) progressively acquire mutations in oncogenes and tumor suppressor genes with deregulation of cell proliferation and differentiation leading to malignancy Location: - 60% Head - 15% Body - 5% Tail - 20% Diffuse Poor prognosis: 5 yr survival rate (5%) Related to location, late presentation/symptoms/advanced disease at diagnosis *** there is not sensitive screening test/serum marker yet for identification of Pancreatic (Adeno)Carcinoma! One has yet to be discovered

Marasmus

A chronic condition of semi-starvation leading to growth retardation Caloric intake is relatively less than protein intake - associated with weaning to low calorie foods (gruel from "native grains or cereals, dilute formula) Sxs: Emaciation, lack of subcutaneous fat, anemia, and weakness, muscle wasting - due to failure of breast feeding and use of over diluted formula and infection from contaminated water supply

Abetalipoproteinemia

A defect in both B-48 and B-100 production and results in a failure of distribution of lipids from the intestine - as a result, TAGs accumulate in the intestines and in the liver - characterized by failure to thive, steatorrhea, developmental delays, hypocholesterolemia. Fat absorption is severely affected

Dietary DONT's:

A heathy eating pattern limits: - saturated fats and trans fats, added sugars, and sodium Consume less than: - 10% of calories/day from added sugar - 10% of cal/day from saturated fats - 2,300 mg/day of sodium - If alcohol is consumed, it should be consumed in moderation- up to one drink/day from women and up to two drinks/day for men

Lipoprotein A

A lipoprotein particle like LDL - also contain apo-lipoprotein(a), apo(a) Simulates LDL but apo(a) covalently linked to apoB-100 - Concentrations are highly variable among individuals and genetically determines - NOT known to be vital - High Lp(a) is a risk factor for CVD - Competes with plasminogen for plasminogen activator (Lp(a)) is structurally homologous to plasminogen- the precurosor of a blood protease whose target is fibrin, the main protein component of blood clots - it is hypothesized that elevated Lp(a) slows the breakdown of blood clots that trigger heart attacks because it competes with plasminogen for binding to fibrin - Genetic element - Estrogen decreases it while trans fats increases it ** Estrogen decreases both LDL and Lp(a) ** Niacin reduces Lp(a) and raises HDL

Changes in compliance

A reduction in compliance decreases the change in volume for any given change in blood pressure Can result from: - constriction (dynamic compliance) - age (static compliance) - arterial disease (static compliance) ** Age increases vessel stiffness- which decreases compliance Stiffness (or Elastance) is the reciproval of compliance Stiffness= change in pressure/ change in volume

Mediastinum

A septum or space in the thoracic cavity - contains the thoracic viscera EXCEPT the lungs Subdivided into: Superior and (via Sternal angle "angle of Louis") Inferior which has: - posterior - middle ** where heart and great vessels are** - anterior NOTE: there are NO tissue planes separating mediastinal compartment

Transillumination

A simple method to detect abnormalities by passing a ight through a part of the body (commin in pediatrics) - req. a dark room - bright light is applied to the side of the scrotal enlargement - if the light transmits a red glow --> indicates there is only serous fluid in the scrotum (hydrocele can be diagnosed, possible to tap and safely drain the hydrocele) - if light is NOT transmitted --> indicates a more serious problem

Which gastric motility effectors speed gastric emptying?

A state of increased pressure and reduced resistance is needed Increased motility, increased pressure are achieved with: - ACh (vagus) to myenteric plexus- long loop - Distension (meal size) - Gastrin - Motilin (non-digestive only)- when no food in stomch *** parasympathetic (excitatory) Reduced resistance, by decreasing pyloric tone is achieved by: - intrinsic signals (proximal to pylorus) - VIP (vagus) *** parasympathetic (inhibitory)

Lipoproteins have 2 principal components which are:

Lipids: - differ according to the type of lipoprotein (but mostly cholesterol, TAG, fat) - depends on what is being transported- different lipids occur in various combinations - Lipid components of lipoproteins come in two parts 1) Outer shell: predominantly phospholipids (i.e. phosphatidylcholine, phosphatidyl ethanolamine) , also un-esterified cholesterol 2) Core: TAGs, and ESTERIFIED cholesterol (cholesterol esters, CE)- these are more hydrophobic so end up in the core- have most of the carrying capacity Apo-lipoproteins (the proteing component): - structural function - recognition There are 5 major classes of Apolipoproteins: - A-I, A-II (structural) - B-48, B-100 (structure and recognition) - C-I, C-II, C-III (activates) - D (unknown function) - E (targets lipoproteins to various tissues) * These are classes according to structure and function: Some... - identify particles - interact with LPL (lipoprotein lipase- releases FA from TAG in core) - are recognition sites - serve a structural role in creating the particle - exchahnge between particles

The Hepatic Portal vein carries all nutrients (carried in venous blood) from the GI tract DIRECTLY to the

Liver ** Blood in the hepatic portal vein has a slightly higher oxygen content than the venous blood in the systemic/caval system --------------- This is different from the Hepatic veins which drain blood AWAY from the liver and back to the systemic (caval) system - The central veins of the liver unite together and drain to form the Left, Right, and Middle Hepatic Veins respectively --> these drain into the IVC --> drains into the Right atrium of the heart * The relationship between the hepatic veins and the inferior vena cava helps to keep the liver in position: in addition to the ligaments of the liver

Bile acids are synthesized in the

Liver by multistep, multiorganelle pathway -OH groups are inserted at specific positions on steroid structure - DB of cholesterol B ring is reduces - hydrocardon chain is shortened by 3 carbons - a charge carboxyl group is introduced at end of chain * the most common resulting compounds are Cholic Acid (a triol) and Chenodeoxycholic Acid (a diol) are called "primary" bile acids- they are extensively modified in the liver and intestine - primary bile acids have a free -COOH, they are synthesized in the liver from cholesterol and then conjugated * in intestines they act as surfactants to solubilize fat and other hydrophobic compounds for digestion and uptake

Sources of Vitamin B6, pyridoxine

Liver, fish, whole grains, nuts, egg yolk Deficiency is rare but can occur with alcoholism, in infants on formula low in B6, and women taking oral contraceptives Sxs: - Glossitis (inflammation of the tongue- it is often smooth and reddened due to loss of papillae), dermatitis, and sideroblastic anemia (MICROcytic bc heme synthesis is impaired- defective RBCs that remain nucleated and have a nucleus surrounded by mitochondria) Toxicity: - toxic in high doses (unlike other water-soluble vitamins. Neurological sxs occur at 500mg/d (400x the RDA and 5x the upper limit) ** but note that at high doses (not as high to reach toxicity) but aroung (~100-150mg/d) it can be used to treat carpal tunnel syndrome

Pericytes (AKA rouget cells)

Located on some continuous capillaries (and some post capillary venules) Functions: - contractile which helps move blood through capillaires - gives rise to SMCs during vessel growth in development and wound healing

Conducting System of the Heart

Located within the subendocardial layer of the endocardium and the myocardium Consists of: SA node AV node Atrioventricular (A-V) bundle of His Purkinje Fibers

Ovarian cancer begins in the ovary and spreads to the

Lumbar l.n first - lymphatic vessels drain by following the ovarian veins

Prolonged spasm and sclerosis of resistance vessels (small muscular arteries and arterioles can lead to:

Lumen narrowing --> tissue ischemia --> sclerosis and atrophy, infarction or Vessel wall injury --> increased vascular permeability --> edema and hemorrhage

Metastatic spread for carcinoma in the Testes can occur via the

Lymphatic system - Lumbar (para-aortic) lymph nodes first (but can travel all the way up to the lungs) - these retroperitoneal lymph nodes lie just inferior to the renal veins and are parallel to the abd aorta - cancer of the testes (testicular carcinoma) could eventually reach the lungs (via the mediastinal and supraclavicular lymph nodes) NOTE: metastatic spread can also be via the vascular system - cancer of the testes could eventually reach the liver and spine - the valveless veins that form the internal vertebral venous plexus can provide a pathway for cancer cells to spread to the brain

Conduction System of the Heart is regulated by the

ANS - Vagus provides PARAsympathetic Innervation: SA and AV nodes and coronary arteries- SLOWS HR - Thoracic cord segments T1-T5 SYMPATHETIC to the above- INCREASES HR *** NOTE: visceral afferent fibers travel with (hitchhike) sympathetic fibers and carry the visceral pain relating to angina pectoris "pain in the chest" Conduction System: Facilitates normal beating of the heart (it can increase of decrease in response to parasymp or symp): 1. SA node - in R. atrium between crista terminalis and opening of SVC 2. Bachmanns Bundle - right to the L atrium 3. AV node - Located in the right atrium at interarterial septum close to the opening of the coronary sinus 4. Bundle of HIs - In the membranous part of interventricular (IV) septum 5. Right and Left Bundle Branches - both in muscular IV septum - R. is in moderator band, wall of R ventricle - L. is in wall of L ventricle 6. Purkinje fibers (subendocradial brs.) - R side: IVS, wall of R ventricle, ant. papillary muscle - L side: IVS, wall of L. ventricle, and post. papillary muscle

Metastatic spread for carcinoma of the skin of the scrotum is most likely via the

Lymphatic system BUT via the Superficial Inguinal Lymph Nodes first (*remember for tetes it was to lumbar (para-aortic) lymph nodes first) think "Scrotal - Superficial" - the sup. inguinal l.n lie in subcutaneous tissue - inferior to the inguinal ligament --- Symptoms: - slow growing skin lesion - often ulcerated - lump on skin of scrotum - may be painful or painless - microscopic examination of biopsy can confirm if cancerous * Dr. Pott's identified the increased risk chimney sweeps had for developing scrotal cancer

The cystic veins drain blood ___ from the gallbladder

AWAY - it is common to find multiple cystic veins - most small veins from the body of the gallbladder pass directly into the hepatic sinusoids that are within the liver - most larger cystic veins around the neck of the gallbladder drain into the hepatic portal vein

Distal Large Intestine Summary Above and Below the Pectinate Line

Above Pectinate Line: - Venous: portal venous system (goes to liver) - Lympathics to internal iliac lymph nodes - Visceral innervation: Parasymp.--> Pelvic splanchnic nerves (S2-S4), Symp.--> Lumbar Splanchnic Nerves (L1-L3) Below Pectinate Line: - Venous: Systemic (caval) venous system - Lymphatics go to the superficial inguinal lymph nodes - SOMATIC innervation --> Inverior rectal nerves (very sensitive to pain) ** NOTE the descending & sigmoid colon, and proximal rectum lymphatics drain to the inferior mesenteric lymph nodes

Hirschsprungs Disease (AKA congenital megacolon)

Absence of parasympathetic ganglion cells in the myenteric and submucosal plexus of the distal colon/rectum * ganglion cells are derived from neural crest cells and migrate caudally with the vagal nerve fibers along the intestine, they arrive in the proximal colon by 8 weeks of gestation and in the rectum by 12 weeks * arrest in migration leads to an Aganglionic segment which is unable to relax, leading to a functional colonic obstruction at that point -- *remember that the myenteric plexus is found between the inner circular layer and outer longitudinal muscle layers

During FORCES RESPIRATION when there is an increased demand for oxygen (ex. in exercise or disease (COPD)), the ___ are used

Accessory Muscles of Respiration - Neck muscles (ex. sternocleidomastoids/scalenes elevated sternum and ribs 1&2) - Rectus abdominis, external oblique, transverse abdominis (pull ribcage downwards) - Pectoralis major and Latissimus Dorsi (fixing the shoulder girdle will pull the ribcage outwards) *** These muscles can be seen hard at work in patients with respiratory distress (Ex. Acute Asthma, COPD or in athletes at the end of hard race)

What occurs in the Pancreatic acini vs. the pancreatic ducts

Acinar cells are the site of INITIAL PRODUCTION and secretion of pancreatic juice, including pancreatic enzymes and proenzymes Ductal cells are sites of MODIFICATION of the primary fluid such that the final fluid is high-volume when necessary and rich in bicarbonate as well (will have diff. composition than acinar fluid) ----------- Like in salivary glands... - most of the proteins found in pancreatic juic are secreted along with a primary salivary juice by acinar cells - there is extensive modification of this primary secretion by duct cells UNLIKE salivary glands: - there is one final exit point for all pancreatic juice, the Sphincter of Oddi at the duodenal wall- this typically opens during periods of pancreatic and gallbladder secretion, which again is typically in the presence of nutrients in the duodenum and jejunum

Lipids are turned over in

Lysosomes * Lysosomal Storage Disorders= failure in degradation of gangliosides or globosides - so lysosomal storage diseases occur due to failure to break down glycosphingolipids (which are constantly tunred over- they are synthesized and degraded as a normal part of cellular metabolism) Breakdown of glycosphingolipids occurs through: - successive removal of sugar residues by specific glycosidases in the lysosomes - removal of all sugars leads to ceramide - removal of the amide-bonded fatty-acyl group leads to sphingosine Most important diseases to know are: - Tay Sachs - Gaucher - Niemann-Pick - Fabry

The Main pancreatic duct and common bile duct drain into the

MAJOR duodenal papilla

Most ion channels are essentially specific for a particular ion BUT others allow more than one ion to pass through- these are called

MIXED conductance channels * NOTE: ions are charged species and so are excluded from the membrane bilayer- this is why you need ion channels to facilitae their movmeent across the membrane

Dietary Protein Recommendations

Adults 10-35% of calories Male: 56g req. for 2,200 Cal diet Female: 46g req. for 1,800 Cal diet - Varies somewhat with age, gender, activity level Sources: - meats, fish, eggs, poultry - nut seeds, soy products - legumes (beans and peas) * recommended minimum of protein is ~ .8g/kg body wiehgt/day - for athletes: 1-1.6kg body weight.day ex. Person weighing 60kg: 60kg x .8= 48.0g protein/day - protein yields 4cal/g - the amt of protein consumed relative to your basic needs will determine the overall nitrogen balance

Adverse effects and contraindications of CCBs

Adverse effects: HA/ flushing/ edema/ dizziness (all do to vasodilation) ** Edema appears to be related to both vasodilation as well as changes in hydrostatic pressure (change in calcium) Contraindications: Non-DHPs: ventricular dysfunction, SA/AV conduction disturbances, Systolic BP <90mmHg ** Caution with Verapamil and Digoxin ( Verapamil inhibits digoxin metabolism --> Digoxin toxicity)

In active Potassium Secretion in the colon

Aldosterone increases the number of apical potassium channels making it easier for potassium that had been pumped into the cytoplasm with the basolateral sodium-potassium pump to cross the apical membrane into the colonic lumen - this is a small amount compared to that happening in the kidney but it is still present

The large intestine can be found in which quadrants of the body

All 4 quadrants - cecum - ascending colon - transverse colon - descending colon - sigmoid colon - rectum - anal canal

Main effect of CCBs on cardiac myocytes

All agents can have negative inotropic effect (reduced contractility) - less Ca2+ entry, and less CICR from SR --> reduced contractility DHPS: - increase vasodilation, concurrent baroreceptor reflex increases sympathetic outflow which will OFFSET the negative inotropic effect Non-DHPS: - impact on contractility depends on agent (diltiazem < verapamil) - as they effectively blunt the SNS response, there is NO OFFSET of negative inotropy (NO tachycardia with NON-DHPS)

Therapeutic uses for Antacids

All antacids are used for treatment of intermittent heartburn and dyspepsia Additional uses of individual agents: - Magnesium Hydroxide: can be used as laxative- for relief of occasional constipation (osmotic laxative) - Calcium Carbonate: can be used for hypocalcemia/osteoporosis prevention and hyperphosphatemia ** commonly known as TUMS - Sodium bicarbonate (combo: aspiring + citric acid): can be used for heartburn, acid indigestion, sour stomach accompanied by headache or body aches/pains. Contains aspirin which can exacerbate or cause ulcer disease ** commonly known as Alka Seltzer

Endocardial Cushion defect with Ostium Primum Defect

An Atrial Septal Defect Defect in endocardial cushions and AV septum - Thus septum primum does NOT fude with endocardial cushion - Results in patent ostium (foramen) primum - will often have a MITRAL VALVE DEFECT associated with it called a MITRAL VALVE CLEFT ( a slit-like or elongated hole usually involves the anterior leaflet of the mitral valve ** ACYANOTIC

Probe Patent Foramen Ovale

An Atrial Septal Defect - Present in up to 25% of individuals - A probe can be passed from one atrium to other through the superior part of the floor of the fossa ovalis - Not clinically significant as usually small, but they may be forced upen because of other cardiac defects and contribute to functional pathology of the heart (INCREASED RISK OF MIGRAINES) Results from: incomplete adhesion between the original flap of the valve of the foramen ovale and the septum secundum after birth

Sinus Venosus Defect

An Atrial Septal Defect A sinus venosus atrial septal (RARE) defect, occurs in the interatrial septum close to the SVC - results from incomplete absorption of the sinus venosus into the RA and/or abnormal development of the septum secundum - Ppl with this often have a problem with the pulmonary vein/s, which may be attached to the RA instead of the LA *** This ASD requires surgical repair ** ACYANOTIC

Ostium Secundum Defects

An Atrial Septal Defect These are defects in the region of the fossa ovalis and include defects of the septum primum and septum secundum. Variations include: - Resorption of septum primum in abnormal location - Excessive resorption of septum primum - Defective development of septum secundum - Combination of excessive resorption of septum primum and large foramen ovale ** Acyanotic

Porta Hepatis

An anatomic "region", not an anatomic structure - is a deep fissure in inferior surface of the liver through which all the neurovascular structures (EXCEPT hepatic veins) and hepatic ducts enter and leave the liver - it runs in the hepatoduodenal ligament and contains: R and L hepatic ducts - Contains portal vein, common bile duct, hepatic arteries, nerves and lymph nodes

Misoprostol

Analog of PGE1 - Agonist at prostaglandin receptors (EP3 on parietal cells) Pharmacological effects: - stimulates mucus, electrolyte, bicarbonate and fluid secretion in the GI system - enhances mucosal blood flow - reduces histamine-stimulated cAMP production and gastric acid secretion - stimulates intestinal motility - stimulates uterine contractions ** works in stomach and uterus

Portal Hypertension can lead to Esophgeal Varices

Anastomosis between: Portal System: L and R gastric veins Caval System: Esophageal veins - In severe cases of portal hypertension, the blood is unable to effectively flow through the liver which causes retroflow in the gastric veins which change to drain into the esophageal veins instead ** this is potentially fatal if one of the fragile, dilated esophageal veins gets damaged and excessive bleeding occurs

Caput Medusa

Anastomosis between: Portal System: Paraumbilical Veins Caval System: Epigastric Veins - In sever cases of portal hypertension, blood is unable to effectively flow through the liver which can cause retroflow in the paraumbilical veins which now drain into the periumbilical veins * The superficial veins of the anterior abd. wall (superficial epigastric and thoracoepigastric) then become extremely dilated and varicose which over time looks like snakes slithering under the skin

Hemorrhoids

Anastomosis between: Portal system: Superior rectal veins Caval system: Inferior rectal veins Internal Hemorrhoids: - Found ABOVE the pectinate line - will NOT be painful --> visceral innervation - if damaged then would result in BRIGHT RED blood in the stool (as this is close to the source and the blood has not be digested) --> Lower GI tract bleed External Hemorrhoids: - Found BELOW the pectinate line - Would be extremely painful--> SOMATIC innervation - Develop from varicose perianal veins that are part of the caval system

The liver can be described as having lobes that are classified differently by anatomists and clinicians. What are the different classifications?

Anatomical lobes (4): 1. Right 2. Left 3. Quadrate (associated with gallbladder) 4. Caudate (associated with inferior vena cava) Functional lobes (8): These are based on the blood supply * this is why independent segments can undergo surgical resection (so if there is cancer in one functional lobe of the liver it can be resected because it has its OWN blood supply) * you will NOT be asked to name these 8 lobes

Continuous capillaries

MOST common and least permeable type of capillary - a continuous layer of endothelial cells, attached by tight junctions, sit on a continuous basal lamina - found in muscle tissues, CT, nervous tissue, lung and exocrine glands *** These are MOST common

Heart valves Anatomical Location vs. Auscultation Sites

Anatomical: Aortic Valve: medial aspect of the left 3rd intercostal space, behind the sternum --> Auscultated @ 2nd intercostal space, right parasternal area Pulmonic valve: medial aspect of the left 3rd costal cartilage --> Auscultated: 2nd intercostal space, LEFT parasternal area Tricuspid Valve: medial aspect of right 5th costal cartilage, behind sternum --> Auscultated: 5th intercostal space, LEFT parasternal Mitral Valve (Bicuspid Valve): medial aspect of the left 3rd intercostal space --> Auscultated: 5th intercostal space, LEFT midclavicular line "ALL PHYSICIANS TAKE MONEY" *** Auscultation is performed at the sites where the sound wavese reverberate- NOTE at the anatomical location of the valves

With continues growth of the liver and modification of the mesentery the lobes are formed- which can be describe anatomically of functionally

Anatomically (4) - right - left - quadrate (next to gallbladder) - caudate (next to IVC) Functional lobes (9) - based on blood supply, independent segments can undergo surgical resection ** Porta Hepatis= "hilum" of the liver where abd structures can enter or leave - the hepatic veins drain blood away from the liver and when blood is exiting it does not pass through the porta hepatis --> instead the hepatic veins drain posteriorly to the inferior vena cava

Superior Thoracic Aperture (STA)

Anatomically--> Thoracic inlet Clinically--> Thoracic outlet Boundaries: T1 vertebra 1st rib & costal cartilages (R & L) Superior border of the manubrium

Innervation to the Anteriolateral Abd Wall is done via

Anterior Rami of spinal nerves T7 to L1 - intercostal nerves travel in the neurovascular plan between internal and innermost intercostal muscle - when the intercostal nerves pass inferior to the costal margin, they change name to the THORACOABDOMINAL NERVES - typically travel in the neurovascular plane between internal oblique and transversus abdominis muscle

The Arterial Supply of the Scrotum includes:

Anterior Scrotal Branches - come from Femoral A. * Femoral A --> EXTERNAL pudendal A. --> Anterior Scrotal A. and the Posterior Scrotal Branches - come from the abd. aorta * Abd aorta --> Common Iliac --> Internal Iliac A. --> INTERNAL pudendal A. --> Perineal A. --> Posterior Scrotal Artery

List the Boundaries of the Inguinal Canal

Anterior Wall: - External Oblique Aponeurosis (the EXIT of the inguinal canal is located in this wall SUPEROLATERL to the pubic tubercle) Posterior Wall: - Transversalis FASCIA (ENTRANCE of the inguinal canal is located in this wall LATERAL to the inferior epigastric artery and vein) Roof: - Conjoint tendon (formed from the arching fibers of the internal oblique and transversus ABDOMINIS aponeuroses) Floor: - Inguinal ligament (AKA of Poupart): this is the fibrous, thickened, folded margin (inferior edge) of the external oblique aponeurosis- it extends from the anterior superior iliac spine (ASIS) to the pubic tubercle

Boundaries of the omental foramen

Anterior border: hepatoduodenal ligament (AKA free edge of the lesser omentum)- this contains the portal traid: 1. common bile duct 2. Hepatic Portal Vein 3. Hepatic artery proper Posterior border: inferior vena cava and right crus of the diaphragm Superior border: (caudate lobe of) the liver Inferior border: 1st part of the duodenum

Innervation to the Scrotum includes

Anterior cutaneous innervation: - ilioinguinal nerve --> anterior scrotal nerves (L1) - genital branch of genitofemoral nerve: travelling withint the spermatic cord (L1-L2) and Posterior cutaneous innervation: - pudendal nerve --> posterior scrotal nerves (S2-S4) - perineal branches of posterior femoral cutaneous nerve (S2-S3)

Lymphatic of the Duodenum ultimately drain by following the arteries to

Anterior surface towards --> Celiac Lymph Nodes Posterior surface towards --> Superior Mesenteric Lymph Nodes

Sinusoidal capillaries

MOST permeable and the LEAST common type of capillary - DO NOT possess pinocytic vesicles like fenestrated capillaries did - Posses fenestrate but NO diaphragms like fenestrated did - Discontinuous layer of endothelial cells and basal lamina - Display intercellular gaps - great interchange between blood and tissues ---- These are larger than the other types of capillaries - irregular in shape (often tortuous) as they conform to shape of location site- due to discontinous walls *Found in liver, bone marrow, and spleen

2 ways to clear the small intestine of inappropriate irritant substances

Antiperistalsis and Power propulsion - antirperistalsis: forcing duodenal contents into stomach for suqsequent vomiting- depending on source of irritant in intestinal tract (proximal or distal to sphincter of Oddi) either metabolic alkalosis or acidodsis might occur - power propulsion: strong, long-lasting contraction of the circular muscle that propagate for extended distances along the small and large intestines - these :giant" propulsive contractions are considerably stronger than the propulsive circular muscle contractions during the MMC or fed pattern - power propulsion will often result in diarrhea as the colon cannot reabsorb all the water being sent toward it all at once- it can also result in metabolic acidosis as the fluid being lost is more likely to be alkaline than acidic- and remember in the replacement process for this fluid- a by-product of bicarbonate secretion is extra acid in the portal blood * peristalsis is the process that occurs under normal circumstances all the time during the fed state - irritants in small intestine can magnify both antipersitalsis (for vomiting) or peristalsis for the truly powerful and swift emptying of the intestinal tract of the bowel irritants

ApoB-48 and ApoB-100 function in

ApoB-48 - structural protein of chylomircons - a truncated version of B-100 (transcriptional regulation) - specific for chylomicrons ApoB-100 - structural protein of VLDL, IDL, LDL; only apoplipotein of LDL; mediates tissue uptake of LDL (LDL receptor ligand) - full length B apolipoprotein - characteristic of VLDL, IDL, and LDL, and the only apolipoprotein in LDL

A 6-10cm blind intestinal diverticulum in the Large intestine

Appendix (AKA Vermiform "worm") - contains masses of lymphoid tissue - in RLQ like the cecum - intraperitoneal (mobile) - held in place by a short, triangular mesentery called the mesoappendix - arises from the posteromedial aspect of the cecum - Arterial supply: Appendicular artery which travels in the mesoappendix and branches directly from the ileocolic artery Appendix can be in diff. locations for diff ppl: most cases (64%) it is found rectocecal a smaller portion 32% is found in pelvic region in lower proportions it can be found: subcecal, postileal, and pre-ileal

Which is the ONLY MAJOR hormone that modulates small intestinal motility

MOTILIN: it modules the intense motility during Phase 3 of the MMC during fasting state (major effect) Minor effectors: Gastrin, CCK, and serotonin MAY increase small intestinal motility- they are secreted during food processing

Purkinje Fibers

Are located in the Endocardium of the Heart (Deep subendocardial layer) These are Modified cardiac muscle cells that DO NOT contract - Instead they generate and propagate waves of DEPOLARIZATION that spread through the myocardium to stimulate rhythmic cardiac muscle contractions ** Linked to regular cardiac cells via gap junctions and desmosomes: allows propogation of depolarization from purkinje fibers to cardiac muscle fiber *** Purkinje cells are large than adjacent cardiac muscle cells and VERY PALE STAINING ** remember endocardium is associated with the lumen of the heart

Formation of Spleen

Arises in Week 5 within the dorsal mesentery as proliferating mesoderm overlying the dorsal pancreatic endoderm - cells required for its hemopoietic function arise from the yolk sac wall and near the dorsal aorta NOTE: the spleen is NOT a GI organ it is just in the abd cavity- also it is suppled by the Celiac Trunk

Major site of Total Peripheral Resistance (TPR)

Arterioles (and small musclar arteries) represent the site of the greatest change in resistance in the systemic circulatory system - almost ALL resistance in the circulatory system lies in the arterioles and small muscular arteries as they are the major site of sympathetic control of resistance to blood flow

Metabolic theory of blood flow regulation

Arterioles are sensitive to local metabolites and paracrine agents, which can cause local dilation or constriction such as: - Metabolites: adenosine, lactate, H+, K+ - Paracrine agents: Ang II, Histamine, bradykini, prostaglandins (PGFs, constrict; PGEs, dilate) - Other: decreases O2, increases CO2 (produce local dilation) ------ Histamine: produces by mast cells in response to tissue injury and allergic responses and causes vasodilation and increases capillary permeability (exudate as in insect bite) Prostaglandind (part of large family of arachadoinc acid metabolites)- can have both vasodilator and vasoconstictor activities Ex. the F family of prostaglandins (PGFs) are mainly vasoconstrictors wheres family E (PGEs) are vasodilators

What enzyme is deficient in Metachromatic Leukodystrophy (MLD)

Arylsulfatase A - Sulfatides in NS, liver, and kidney accumulate Sxs: difficulty walking, muscle wasting and weakness, blindness, convulsions, impaired swallowing, paralysis, dementia (infantile), dementia, juvenile and adult psychiatric disorder * autosomal recessive

In terms of the "migrating" aspect how does the Migrating Motor Complex work

As one section of the intestinal tract is at its maximum contraction, the section just distal (caudal) to that section is only at phase 2 and the location distal to THAT is still in phase 1 - this means that the pressure gradient between the strongly contracting and quiescent areas of the gut forces even large, otherwise-hard-to-move material (ex. a quarter) along the gut - this slow but inexorable wave takes 2-4hrs to pass from the beginning of the duodenum to the end of the ileum- along the entire length of the small intestine one might observe two or 3 distinct regions that are each in phase 3

Myogenic Theory of Blood Flow regulation- Myogenic Reflex

As protective mechanism, smooth muscle cells can contract in reflex manner when stretched excessively - increase in flow --> increase vessel stretch (excessive --> depolarization of smooth muscle (to -40mV which activates L-type Ca2+ channel)--> smooth muscle cell contracts (vasoconstriction) --> decreased flow *** Smooth muscle has tendency to contract when stretched excessively - to return flow towards normal values

Decompensated shock

As shock progresses, the compensatory mechanisms (i.e. increasing HR and vasoconstriction) reach their maximum ability and cannot increase further - this leads to decompensation Metabolic demands are NOT met, and cellular ischemia results in the release of vasoactive mediators which lead to: - hypotension and dyspnea (shortness of breath) - acidosis - cool, pale skin - mental confusion (dilirium) ** phase of hypovolemic shock

The second part of the large intestine that connects the cecum to the R colic flexure (aka hepatic flexure) where it becomes the transverse colon

Ascending Colon - located in both the RLQ and RUQ - secondarily retroperitoneal (becomes retroperitoneal in development) - R paracolic gutter is located laterally (allows peritoneal fluid to drain sup --> inf.) - narrower than the cecum * the R colic (hepatic) flexure is closely related to the inferior surface of the liver and 9th-10 ribs Arterial supply= R colic artery which is typically a direct branch of the superior mesenteric artery

Of the water soluble vitamins listed the RDA for _____ exceeds the rest

Ascorbate (Vitamin C) RDA= 75/90mg

Describe the process of gastric emptying

At 1-2 mm in diameter most food chunks are small enough to pass the pyloric sphincter into the duodenum - a small quantity of this chyme of acid and very-small-food-chunks is emptied through the pylorus with every increase in antral pressure, such that every wave of peristalsis normally produces a "squirt" of a small amt. of digestible material into the duodenum (this is gastric emptying) * its proper control is critical to ensuring that efficient digestion and absorption of nutrients takes place in the small intestine

Thanks to _____ cerebral blood flow will be maintain relatively normal even in the face of substantial changes to MAP

Autoregulation ** important in hemorrhage and hyeprtension 60-180mmHg is the MAP range at which organs such as the brain and heart maintain a constant flow *** even in case of hemorrhage- cerebral and cardiac blood flow will be maintained relatively normal even in the face of substantial blood loss --- An increase in MAP from normal up to 180mmHg does NOT increase flow due to myogenic theory (reflexive vasoconstriction of cerebral vasculature) A decrease in MAP from normal down to 60mmHg will NOT decrease flow due to metabolic theory (vasodilation and increased flow would result from metabolic theory due to high PCO2 (in the brain) and other metabolites like adenosine in the heart

Wilsons Disease

Autosomal recessive condition due to mutation in ATP7B gene (which encodes Cu+2-ATPase) ** So the basic defect causes failure of the copper-transporting ATPase which transports copper into the ER/Golgi for coupling to ceruloplasmin and excretion into bile and secretion to plasma- this results in insufficient coupling to the copper carrier, ceruloplasmin, and high free copper levels accumulate - Copper accumulates in liver and brain leading to dementia and movement disorders (Kayser-Fleisher Rings- copper colored rings appear in the eyes) *** Damaged liver function results in very low ceruloplasmin and high circulating free copper in the blood *** Treatment is copper chelation using Penicillamine

Water soluble vitamins include

B- Complex A. Energy-releasing Thiamine (VitB1) Riboflavin (VitB2) Niacin (Vit B3) Biotin Pantothenic acid *** these are involved in glycolysis, TCA, oxid. phos. etc. B. Hematopoietic Folate (Folic acid) VitB12 C. Other Pyridoxine (VitB6) Pyridoxal Pyridoxamine Choline Non-B-Complex: - Ascorbic acid (VitC) ** many of these do not have an UL bc many are used quickly * more prone to deficiency * excreted in the urine- therefore they are rarely toxic * typically involved as enzyme cofactors or prosthetic groups Ex: Thiamine, Riboflavin, VitB12, Pantothenic acid, and Biotin do not have an upper limit

Infra-peritoneal organs (AKA Subperitoneal)

BENEATH the peritoneal cavity - only part of its surface is covered by peritoneum Ex: - rectum: distal 2/3rds - urinary bladder

What are some adverse effects of Metoclopramide?

BLACK BOX WARNING: treatment with metoclopramide can cause tradive dyskinesia (a serious movement disorder that is often irreversible) - other significant CNS effects: depression, extrapyramidal symptoms (acute dystonic reactions- symptoms involuntary muscle movement, facial grimacing and toricollis), parkinsonian-like symptoms (bradykinesia and tremor) - hyperprolactenemia- elevated prolactin: may lead to galactorrhea, amenorrhea and gynecomastia ** Not many drug interactions seen with this ----- Clinical uses of Metoclopramide: - **** Primarily used fo Diabetic Gastroparesis (imparied gastric emptying): metoclopramide works to increase gastric emptying - Advancement of nasoenteric feeding tubes - GERD (not the preferred treatment: may be used in combo with a PPI for patients with refractory heartburn or regurgitation - Antiemetic: prevent post-operative nausea and vomiting, prevent nauses and vomiting associated with chemotherapy

Gastric accomodation vs. Receptive Relaxation

BOTH are vagally-mediated relaxation of gastric wall in the fundus region - Gastric accomodation is BEFORE food is swallowed (cephalic phase)- preps to relax, decreases pressure - Receptice relaxation is AFTER swallowed food enters the stomach (gastric phase)- using the ENS * These related processes: - keep pressures low from empty through low then moderate filling of the stomach - they are limited: with high to extreme stomach filling, pressures rise as volume increases - make it easy to store food in the fundua - keep the antrum free of stored food so it can begin the process of grinding/digestion ** there can be a big increase in volume w/o changing the stomach storage capacity this is called compliance - elasticity is the opp.- you have a big push back Clinical: Bariatric surgery reduces the stomachs storage capactiy

The liver is covered by visceral peritoneum EXCEPT at the

Bare area- where it is in contact with the diaphragm - Around the margins of the bare area, peritoneum makes a fold or reflection (coronary ligament (superior and inferior portions)) - Coronary ligament ultimately ends at the lateral edges of the liver as the left and right triangular ligaments

Functio of the Foramen Ovale

Before birth: - allows most of the oxygenated blood entering the RA from IVC and SVC to pass into the LA thereby bypassing the lungs ** NOTE: septum primum valve- prevents backflow of the blood After birth: - pressure in LA increases as the blood returns from the lungs which are now functioning Results: Septum primum pressed against the septum secundum and adheres to it and the foramen ovale is closed

Formation of the Pancreas

Begins as 2 endodermal outgrowths from the primitve foregut: - small ventral pancreatic bud and a - large dorsal pancreatic bud ** there is then primary rotation of the gut tube - this primary rotation causes the ventral and dorsal buds to merge (fuse) in week 6 together into what is usually a SINGLE organ in the adult - Ventral pancreatic bud comes to lie posterior to the dorsal bud - The massive Dorsal bud gives rise to the heady, body and tail of the pancreas (this is most of the pancreas) - The ventral pancreatic bud forms the Ventral uncinate process ** CT and blood vessels are formed from the surrounding mesoderm ** as these two buds unite do does their ductal system

Benefits and challenges of measurements

Benefits: - sets stage for improvement - identifies patterns and trends - helps us see how well performance matches goals - helps us focus on what is important - helps "sell" our ideas to management - provides common fram of reference for everyone involved - moves us away from anecdotes and one persons view or opinin Challenges - time consuming - can you get "buy in" from ppl doing the work - can you use the data you callect to actually take action - accurate and consistent data? - appropriately meaure what you need to know and make a change? - relevant? - consequences of undesirable findings?

Beta Blockers vs Calcium blockers

Beta Blockers: Metaprolol - RISKY USE IN: bradycardia, hypotension, bronchospasm - Useful in: high adrenergic state, exercise-induced Afib, Heart failure *1st line therapy CCBs: Diltiazem and Verapamil - RISKY IN: bradycardia, hypotension, can worsen heart failure - Useful in reactive airway disease ** use as alternative to beta-blockers, avoid in heart failure *** These nondihydropyridine calcium channel blockers should NOT be used in pts with LV systolic dysfunction and decompensated HF bc of neg inotropic effects, BUT they may be used in patients with HF with preserved LV systolic fx

A pt with Afib and...... No other CV disease| Or someone with HTN or HFpEF (heart failure with preserved ejection fraction) | or Someone with COPD can be given

Beta blocker Diltiazem Verapamil -------------- Someone with Afib and LV dysfunction or HF can be treated with a - Beta blocker - Digoxin -- NOTE: In Afib beta-blockers are first-line candidates, and CCBs are also first line EXCEPT in HF with LV dysfunction ** Beta blockers should be used following stabilization of pts with decompensated HF

Which enzyme is defficient in Tay-Sachs Disease

Beta-Hexosaminidase A - GM2 ganglioside especially in brain neurons accumulates Sxs: mental retardation, blindness, muscle weakness, seizures, cherry-red macula, early mortality - can be infantile, juvenile/adult * this is autosomal recessive * more common in ashkenazi jews

What enzyme is deficient in Krabbe disease?

Beta-galactosidase - Galacto-cerebroside accumulates: presence of globoid cells, breakdown of myelin in nerve, destruction of brain cells Sxs: mental and motor deterioration, irritability, fever, seizures, vomiting, feeding difficulties, muscle weekness, deafness, blindness

Which is more water-soluble? Cholesterol or Bile Acid

Bile acid has more polar groups attached to the original four rings of cholesterol than has cholesterol, therefore a bile acid is more water-soluble on that side than is cholesterol - Most bile acids are conjugated with organic molecules to further increase the realtive water solubility on that side of the molecule, amplifying the amphipathic nature of each bile acid - the most typical components covalently attached during the conjugation process are either glycine or taurine molecules --- once combined with these organic molecules, these now-conjugated bile acids are called bile salts

What type of secretion is bile?

Bile is an exocrine secretion - typically 500mL/day (this increases if we eat more FA- consumption of many or few fat-rich foods during the day will affect the overall secretion rate) - bile contains bicarbonate, bile salts, and many waste products - bile components make lipid digestion much more efficient ** most of the bile salts will be recycled via the enterohepatic circulation ------ The actual amount of bile produced by the liver is actually closer to 1L/day but the gallbladder typically reabsorbs almost half of that volume, so the net volume secreted into the duodenum is closer to half a liter/day

Describe the composition of bile

Bile is secreted by the liver, typically 500mL/day but up to 1L/day - excreted through bile duct into pancrea, from there to duodenum Composition: organic molecules such as: - cholesterol - cholesterol-derived bile acids and bile salts (ex. Cholic acid and Chenodeoxycholic acid) - bile pigments (ex. bilirubin which is derived from Hb)- thsese molecules have no digestive function but it is a convenient way to excrete these molecules - phospholipids (ex. lecithin) - many ions including HCO3-, Ca++, Na+, K+, and Cl-, also some heavy metal ions that should not be present in the body but which are absorbed by the GI tract like silver ions, Ag++ - water its pH can be anywhere from 6.0-7.5 (slightly acidic/slightly basic but never at an extreme)

Describe the structure of the Biliary Tree

Bile withint the R and L hepatic duct combine in the common hepatic duct -Cystic Duct connects the common hepatic duct and the gallbladder (half of the hepatic bile output is diverted to the gallbladder through this duct, gallbladder bile must pass through it to) - Both hepatic bile and gallbladder bile then move through the common bile duct - Bile meets with pancreatic juice in the ampulla of Vater and exits into the duodenum *** the Sphincter of Oddi normally keep the ampulla of Vater separated from the duodenal lumen ------- NOTE: most of time the sphincter of oddi is closed and the sphincter at the cystic duct is open - this means that most of the time the bile being produced by the liver has a pressure gradient towards the gallbladder lumen, and resistance points that favor movement of material from the bile duct into the gallbladder - this allows the liver to keep "detoxifying" the body of harmful metals, excess cholesterol etc. all the time even between meals, and the bile flow into the concentrating organ is a useful side effect of this process ***** Clinical: Gallstones form when products concentrated in this gallbladder bile fall out of solution and form solid masses

H2-Receptor Antagonists

Block Histamine Include: Histamine, Cimetidine, Ranitidine, and Famotidine Pharmacokinetics: - Oral, IV, and IM - Half life varies 1-3.5hrs - Little to no protein binding - Renal Elimination Adverse Effects: - Most common= low and minor.. Diarrhea, headache, drowsiness or fatigue - Less common: CNS (ex. agitation), thrombocytopenia ** Cimetidine inhibits binding of dihydrotestosterone to androgen receptors and inhibits metabolism of estradiol--> can lead to Gynecomastia, Galactorrhea, and Impotence Drug Interactions: - Cimetidine= CYP (cyp450) drug interaction (cimetidine inhibits it - altered absorption of pH labile drugs

Class II agents- Metoprolol

Blockade of Beta-adrenoreceptors: principle effect in nodal tissue - symp cardiac nerve --> beta-1 receptors --> turns up autonomic tone Inhibition of beta-1 receptors in SA node--> decrease in pacemaker current (If channel) --> decreased rate of phase 4 depolarization --> less frequent firing of node tissue Inhibition of beta-1 receptors in AV node --> decrease in Ca2+ and K+ currents --> decreased conduction velocity --> increased refractoriness of node ** All effects depend on general adrenergic tone

What biological immunological factors are present in the respiratory tract

Macrophages! - Long-lived macrophages are the first line of defense against daily pathogen challenges of the epithelium - avidly phagocytic - able to kill ingessted pathogens - orchestrate inflammatory and adaptive immune responses - act as APCs - secrete IL-10 to avoid unnecessary inflammation Mechanisms of actions: - innate phagocytosis of surfactant protein A (SP-A) and surfactant protein D (SP-D) opsonized pathogens - adaptive phagocytosis of IgG opsonized pathogens - killing by ROS (NO, superoxide ion, OH- radicals, hydrogen peroxis, HCL acid) as well as antimicrobial cationic peptide (beta-defensins, cathelicidins, lysozyme) * secretions of IL-8 to recruit neutrophils when the challenge is sever or persistent and CANT be handled by macrophages alone These are short-lived neutrophils - recruited into alveolar spaces when pathogen challenge is severe Killing mechanisms include: - opsonin-enhanced phagocytosis - ROS - antimicrobial cationic peptides

Motilin is produced by M cells in the duodenum and jejunum. What is its main signal for secretion?

Main signal not well known (thought to be lack of nutrients/absence of food) - food in stomach/intestines inhibits secretion - control of secretion in absence of food is not well understood Pathway of action: endocrine (secreted into blood for delivary to target tissues) Main target tissues: smooth m., from stomach to colon (senses indigestible material that cant be absorbed- helps to break it down) Main actions: stimulate the most intense contractions of gastric/intestinal smooth muscle in the Migrating Motor Complex; help to clear NON-NUTRITIVE components out of the stomach and small intestine * when the intestine is empty of nutrients, it mediates a powerful contractile wave of circular smooth m. peristalsis from stomach to colon

The opening of the common bile duct and the main pancreatic duct are the

Major duodenal papilla (AKA greater duodenal papilla) * this is an elevation of mucosa protruding into the duodenum and is larger due to the hepatopancreatic ampulla and sphincter internally within the head of the pancreas - this opening releases pancreatic juice AND bile

In appendicitis, point tenderness typically occurs at

McBurney Point - anatomically located on a line one-third of the distance between the anterior superior iliac spine (ASIS) and the umbilicus

Driving pressure in systemic circulation=

Mean Systemic Arterial Pressure- RA pressure ** remember MAP= diastolic pressure + 1/3 (P systolic- P diastolic) - RA pressure can range from below atm pressure to just aboce atm pressure as this is affected by inspiration- so a normal RA pressure will be in range of -4 to +4 mmHg * A positive double digit RA pressure- suggests R sided pathology

Driving pressure in pulmonary circulation=

Mean pulmonary arterial pressure- LA pressure MAP= diastolic pressure + 1/3 (P systolic- P diastolic) ** LA pressure is normally higher than RA pressure and the normal rang is 6-12mmHg *** A high LA or wedge pressue > 20mmHg would suggest a left sided pathology

Vascular Compliance

Measures the change in volume produced by a given change in pressure Compliance= Change in volume/ Change in pressure Two types: - Static compliance: a physical property of a vessels, determined by CT/elastic tissue present (elastin/collagen)- altered by age and disease ** vessels with LESS elastic CT usually have MORE static compliance (i.e. veins do NOT have an elastic lamina, thus they have LESS elastic tissue and are MORE compliant) - Dyanmic compliance: is a chnage in vascular tone due to smooth muscle contraction- altered by SNS activity by stimulating smooth m. contraction ** Tone of a vessel- refers to extent of symp innervation of that vesssel which we know is mediated by alpha-1 receptors - so as you increases symp innervation of a vessel you will increase its resistance and therefore increase the resistance to blood flow through it- aka an increase in vessel tone

Churning ______ digests food

Mechanically This includes: 1. Propulsion: - movement of solid particles toward the antrum - propulsive gastric contractions, occlusion of the pylorus (close pylorus) - initiated by the gastric pacemaker (remember its on greater curvature of stomach)- this contraction propels solid particles toward the pylorus 3-4x/minute 2. Grinding: - once a bolus of material is trapped in the antrum, it is chunred to help reduce the size of the bolus, a process called grinding 3. Retropulsion - most gastric contents are returned to the body of the proximal stomach ** this whole process is repeated until particle size is apprx. 1-2mm or smaller * Gastrin ( a hormone mainly secreted by gastric distal body and antrum) is a potent hormone in inducing churning, as it increases both gastric motility in the body/antrum and resistance to emptying at the pyloric sphincter

Significance of Meconium

Meconium= 1st bowel movement - In the intestines as bile is released into the intestines it gives the meconium its charcteristic green color - Meconium will also have hairs (bc baby sucks its thumb), greasy bc of fat) - NOTE: there is NO major digestive function until after birth What if there is no meconium? - lower intestinal obstruction may be the cause and can be associated with disorders such as Hirschsprungs Disease, anorectal malformations, meconium plug syndrome If newborn male passes pale, meconium what could be the problem? - Biliary Atresia- problem with hepatocytes

The microbiota of the gut is made up of millions of species in the gut that are beneficial. These make contributions to the

Metabolome (where we get essential nutrients we dont consume directly Ex. most of out B vitamins) The microbiota also: - prevent pathogenic organism overgrowth - provide basal stimulation of innate and acquired immunity - regulates gut permeability ** req. in gut development both in utero as well as postnatal Types and abundance of organisms vary by organ environment: - bacterial components are best studied - fungal - protozoa ------- NOTE: if one of these microbiota over grows they can become pathogenic--> other microbes will try and attack it with immune system to try and bring it back to symbiotic health - The microorganisms are mixed with food particles by peristalsis A coating of microorganisms also line the gut: - aid in digestion by pre-digesting some organis matter - acts as a barrier to pathogenic species which attack brush border - elicits a low level innate immune response to keep immune system constantly primed for action *** a childs microbiota is NOT fully developed till 6-8months old

What differences between folate and methotrexate keep them from acting like eachother

Methotrexate has an -NH2 group where folate has a carboxyl and a methyl group where folate has a -NH *methotrexate (aka Amethopterin) is used to treat lung cancer, breast cancer, leukemia, lymphoma and osteosarcoma - it is also used to treat various autoimmune diseases

Bulk-forming Laxatives

Methylcellulose, Psyllium MOA: Indigestible, hydrophilic colloids (non-crystalline suspension) and fibers that absorb water and increase stool bulk - produces SCFA that induce peristalsis - increases bacterial mass in the stool Pharmacokinetics: - oral - onset of action= 12-72 hours (usually on higher end of this spectrum) Adverse effects: - bloating Clinical Use: Constipation (usually these are first line of therapy for this, after recommendation of high fiber diet)

Class II antiarrhythmic drugs

Metoprolol ( a beta blocker)

The sinusoidal domain of hepatocytes have

Microvilli, which allows for ENDOCRINE secretions (proteins, lipoproteins) from hepatocytes in the blood and uptake of materials from the blood into the hepatocytes

The heart is location in the ___ mediastinum

Middle Mediastinum- which contains the Pericardium 1. Heart 2. Major vessels - Superior Vena Cava and Inferior Vena Cava (drain into R. Atrium) - Pulmonary trunk (leaves R ventricle and divided into R & L pulmonary aa) - Pulmonary veins (into L atrium) - Ascending aorta (leaves L ventricle)

Tunica Media

Middle Muscular Layer of Blood vessels Composed of: Concentrically arranged SMCs (smooth muscle cells) joined by GAP JUNCTIONs ** permit vasoconstriction and vasodilation of blood vessels ** may contain elastic fibers -- NOTE: Gap junctions are used to join the SMCs in the tunica intima but TIGHT JUNCTIONs were used to join the endothelial cells in the tunica intima layer

Myocardium of the Heart

Middle and Thickest layer Consists of cardiac muscle cells * review what these look like from semester 1 Myocardium is THICKEST in L ventricle because: L ventricle must send blood around systemic circulation- so need a strong ejectron force to send blood out of L ventricle into systemic circualtion

On CT the boundary between the right and L lobes of the liver is the

Middle hepatic vein NOT fissure for the ligamentum teres

Proximal Large Intestine Arterial Supply

Midgut Derivates: Cecum, Appendix, Ascending Colon, Transverse colon (proximal 2/3rds) --Receive branches from the Superior Mesenteric Artery: - Middle- , Right- and Ileocolic Artery (appendicular artery) ------- Venous drainage: ultimately to Hepatic portal vein --> portal venous system (the ileocolic, right colic and middle colic veins drain into the SMV) --- Lymphatics: ultimately drain by following arteries towards --> Superior Mesenteric Lymph nodes ---- Innervation: Parasympathetic--> Vagus (CNX) Sympathetic --> Lesse Splanchnic (T10-T11) and Least Splanchnic Nerves (T12)

During fasting, the primary motility found in the stomach and intestinal tract is the

Migrating Myoelectric Complex, AKA Migrating Motor Complex

Angina is an Ischemic Heart Disease (2 types: Variant and Exertional Subtypes of angina). Its treatmnet often involves

CCBs Variant angina (localized vaso-spasm of coronary artery) - CCB limits spasm Exertional Angina (limited O2 delivery due to artherosclerosis) - coronary artery dilation improves flow, better O2 delivery - decrease myocardial O2 demand due to decreased BP (and some reduction in contractility) - CCB and beta blocker (block SNS response) are often used together ----- * Stable angina pectoris= chest pain, lasts 2-5 min (<20min), alleviated with rest or nitroglycerine

In heart failure (HF) the heart as a pump is providing insufficient CO (due to a number of reasons) Therefore

CCBs are generally avoided: - Non-heart failure: improved ventricular performance (trafe off some inotropy for reduced afterload) - Heart failure: reduced contractility unhelpful in reduced ventricular function (already a low inotropic state)

In exertional angina

CCBs cause coronary and peripheral vasodilation and reducing contractility --> lower BP, lower contractility --> lower afterload = less work

What effects does CCK have on bile secretion?

CCK is secreted when there are fats in the duodenum CCK DIRECT Effect: - potent stimulator of gallbladder smooth muscle contraction CCK INDIRECT Effect: - CCK activates vagal afferent (sensory) ANS neurons, brainstem then sends PNS vagal motor signals to gallbladder and sphincter of Oddi myenteric plexuses *without this ANS stimulation it would be difficult to secrete bile bc the opening of the Sphincter of Oddi to allow for both bile and pancreatic juic to actually ENTER the duodenum is a critical step- thus the increased pressure gradient initiated by CCK and ACh is complemented by reduced resistance to flow at the sphincter of Oddi, in a coordinated activity that results in the actual bile entry into the duodenum - Excitatory ENS motor signals (ACh-mediated) sitmulate gallbladder smooth muscle contraction - Inhibitory ENS motor signals (VIP, NO-mediated) inhibit contraction of the sphincter of Oddi smooth muscle *** since many meals contain both fat and AAs (CCK), these are complementary effects that help to maximize lipid digestion and absorption ----- NOTE secretin also plays role in bile secretion - it is secreted when the duodenal lumen pH falls below 4.5 - secretin directly dignals ductal secretion - by promoting increased bicarbonate and water secretion, secretin also increases the pressure gradient from bile duct to duodenum to further increase flow

What is CFTR?

CFTR is a chloride channel found in most epithelia- it is ATP gated but Cl- only goes down its concentration gradient - as Cl- exits the cells: osmotic pressure causes water to also exit the cell (water is exported via osmosis to balance chloride transport) - Sodium leakage will counterbalance the change in membrane potential ***** IF CFTR is defective or impaired, less water, chloride and sodium exit the cell - in secretory epithelia, this leads to increases in thickness of secretions and higher concentrations of secreted materials (due to lower volumes)- Cystic fibrosis - this also leads to a thick viscous mucous with high enzymes and bile salts which can autoactivate and lead to pancreatitis

Describe the important role of CFTR in the bicarbonate secretion process of the pancreatic ducts

CFTR is activated by several mechanisms including increased cAMP (secretin) and calcium (ACh) - another player in the process ONLY found here, is the ATP receptor on the apical lumen which increase calcium as well - when chloride is secreted, sodium and water follow in a paracellular transport - BUT some of the chloride is also reabsorbed in an apical antiport with bicarbonte ----- As in so many other tissues, carbonic anhydrase is involved in producing the bicarbonate to be secreted + a by-product (hydrogen ion). Unlike many other tissues there is also a means to move bicarbonate into the cell across the basolateral membrane using secondary active transport At the end of the process, sodium bicarbonate and water are secreted into the pancreatic duct lumen, increasing pressures to help "wash out" enzyme-rich acinar secretions ---- Clinical significance: -Hydrochloric acid is secreted/reabsorbed into the blood using a basolateral ATPase in sufficient quantities to react with the stomachs byproduct of bicarbonate withint the hepatic portal circulation - In the end, both in the intestinal lumen and in the portal blood, a normal nonacidic environment should be restored. - Compromise of this process either through vomiting or through taking antacid tablets will have a side effect within the blood, producing an acidosis or alkalosis - Similarly, failure to secrete suffcient bicabonate to neutralize stomach acid will result in the wrong pH for optimal pancreatic enzyme activity and malabsorption may result

Phosphatidylserine is like phosphatidylethanolamine but with an added

COO- PS is found in the inner leaflet of the plasma membrane - it has neg. charged headgroup (PE and PC are zwitterionic) - serves as signal for apoptosis - less common than PC and PE

Maintenance of vascular tone requires external

Ca2+ 3 distinct mechanisms for Ca2+ induced contraction of vascular smooth m.: - voltage-gated ca2+ channels open in response to depolarization --> ca2+ entry - agonist-induced contractions through Gq-PLC-IP3 inducing Ca2+ release from SR (which may alter VG channel behavior) - receptor-operated ca2+ cannels may allow Ca2+ entry

Sources of Vitamin K, Quinone

Cabbage, spinach, kale, egg yolk, liver - it is also synthesized by gut bacteria Deficiency: Unusual, bc it is synthesize in the gut BUT it can occur in infants - newborns often receive a shot of VitK this can help prevent Hemorrhagic Disease of the newborn , as breast milk contains insufficient amounts - other deficiencies are usually uptake disorders - Sxs: clotting disorders TOXICITY: - large doses of menadione (synthetic VitK3) can cause jaundice and hemolytic anemia

What is the most abundant mineral in the body?

Calcium RDA is 1-2g - Bone represents a MAJOR store - No known syndromes due to dietary deficieny, yet calcium intake is often insufficient for optimal bone growth or health Sources: - dairy products (milk), some green veggies, fortified orang juice - UL ~2.5g (TOXICITY is typically only seen with supplements)

Zinc is required for 300+ enzymes such as

Carbonic anhydrase, DNA polymerase, carboxy peptidase, SOD (cystolic form), DNA regulatory proteins (high in DNA binding proteins like Zinc finger protein motifs) Sources of Zinc: - seafood, eggs, meat, legumes and cereals *** WIDESPREAD global zinc deficiency (~1/4 population/ 2 billion ppl, mostly in the developing world) usually due to malabsorption, dietary insufficiency but this is easy to detect because patietns will have loss of taste (dysgeusia) and smell (anosmia), poor wound healing and perioral rash *** this can be treated simply by taking Zinc Supplements- symptoms will go away RDA for zinc ~ 15mg/day *** MOST vitamin and mineral supplements contain zinc

Annular Pancreas

Caused by bifid pancreatic bud - encircles duodenum from both sides - Results in partial or total occlusion of duodenum - Bile-stained vomiting as it is distal to bile duct - If inflammation or malignancy develop in a constricted annular pancreas, blockages can occur

Mechanism of vomiting

Caused by irritation or overdistension of upper GI tract - impulses reach vomiting center in medulla by vagal and sympathetic afferents - it is induced in the vomiting center (in the medulla) by stimulation from 5HT (serotonin) and dopamine from the Chemoreceptor Trigger Zone (CTZ) - motor impulses arise from vomiting center and are carried by CN5 (trigeminal), CN7 (facial), CN9 (glossopharyngeal), CN10 (vagus) and CN12 (hypoglossal) cranial nerves to the upper GI tract and by CN10, sympathetic motor, phrenic and other spinal nerves for the lower GI tract

The Pancreas has Dual Arterial Supply from both the

Celiac Trunk and the Superior Mesenteric Artery -- Anterior and Posterior SUPERIOR Pancreaticoduodenal Artery are branches of the celiac trunk via gastroduodenal artery and the Anterior and Posterior INFERIOR Pancreaticoduodenal Artery which are branches of the Superior Mesenteric Artery

The stomach receives its arterial supply via the

Celiac trunk Lesser Curvature: - L gastric artery (direct branch of celiac trunk) - R gastric artery (branch of proper heaptic artery) * these two anastomose Greater Curvature: - L gastro- omental (gastroepiploic) artery (branch of splenic artery) - R gastro-omental (gastroepiploic) artery (branch of gastroduodeal artery) * these two anastomose Fundus: - Short/ Posterior gastric arteries (branches of splenic artery)

What are the 3 phases of pancreatic secretion?

Cephalic Phase (vagal control) - stimulate: sight, smell, taste, mastication - 25% of max enzyme secretion Gastric Phase (vagal-cholinergic control) - stimulated by distention and gastrin? - 10-20% of maximum enzyme secretion ---- so about 45% secretion is just bc of thinking/swallowing food, it hasnt even hit the GI yet--- Intestinal Phase (feedback control)- from nutrients and acid in duodenum - stimulated by amino acids (reg by CCK) - fatty acids (reg by secretin) - H+ (reg by enteropancreatic reflexes) - 50-80% of maximum enzyme secretion * most pancreatic juice is secreted during the intestinal phase as part of feedback

What enzyme deficiency is present in Farber Disease?

Ceraminidase - ceramide accumulates in joints, CNS, liver, heart and kidney Sxs: Impaired motor and metnal ability, difficulty swallowing, arthritis, swollen lymph nodes and joints, hoarsness (infantile) * milder more rare * autosomal recessive

Which brain disorders may develop in HTN patients

Cerebral infarct and cerebral hemorrhage

Describe the chemical defense of Mucosal immunity in the Genitourinary tract

Chemical defense is mainly due to epithelial cell secretions - beta-defensins - lysozyme - vaginal lactic acid - secretory leukocyte peptidase inhibitory (SLPI) - lactoferrin - cathelicidin - Tamm-Horsfall protein (THP): this is ONLY in the GU tract made from uroepithelial cell it is a protective protein (if its absence prone to UTIs) - urine acidity - nitric oxid

The surgical procedure to remove the gallbladder

Cholecystectomy - the gallblader is NOT a vital organ, therefore if gallstones have a high risk of reoccurence and regularly cause severe biliary colic then an individual may elect to undergo a cholecystectomy to remove the gallbladder *** This is a laproscopic procedure *** to remove the gallbladder you must ligate associated blood vessels (cystic artery) if not blood would flow out *** Once the Cystohepatic traingle is identified the cystic duct and cystic artery are ligated and divided to prevent bleeding and release of bile ** Dissection of the cystohepatic triangle is regarded as the key component to performing a SAFE laparoscopic cholecystectomy

Small lumps of solid stone-like deposits which form in the gallbladder

Cholelithiasis (Gallstones) Relatively common in females and often asymptomatic however, symptoms may include: - pain in the RUQ - pain may be referred to the R neck/shoulder region - nausea - cholecystitis (inflammation of gallbladder) - jaundice (due to obstruction of either the major duodenal papilla or the common bile duct) REMEMBER 4 Fs: Female, Fat, 40, Fertile **** The Hepatopancreatic Ampulla (AKA ampulla of Vater) is a common constricction site where cholelithiasis often become painfully lodged ---- These gall stones can be yellow from cholesterols and and dark brown from pigments

There are 4 type of Lipoproteins which are

Chylomicron (CM), Very-Low Density Lipoproteins (VLDL), Low-Density Lipoprotein (LDL), High-Density Lipoprotein (HDL) Trigylceride transport: - Chylomicrons from intestines: do dietary TAG transport from intestine - VLDL (made in liver): does hepatically synthesized TAG transport export out of liver (more fat or TAG than cholesterol so considered principally a carrier of fat) Cholesterol Transport: LDL: esterified and free cholesterol HDL: esterified and free cholesterol (higher percentage protein and phsopholipids)

Which lipoproteins are responsible for physiological milky appearance of plasma

Chylomicrons -lipid and fat digestion is generally slower than carbs and chylomicrons peak in the plasma at 4hrs after eating and last up to 7 hrs

TAG transport is done via

Chylomicrons and VLDL

Describe the life cycle of Chylomicrons

Chylomicrons are synthesized in intestinal mucosal cells 1. Nascent chylomicrons contain Apo B-48 (truncated form of apo B) 2. Nascent chylomicrons interact with HDL which contributes Apo C-II and Apo E to the chylomicron --Chylomicrons deliver TAG to: Adipose, Cardiac and skeletal muscle--- 3. Lipoprotein lipase (LPL) is activated by Apo C-II on the chylomicron--> LPL hydrolyzes TAGs to free fatty acids and glycerol (the liver has a similar enzyme called hepatic lipase) NOTE: In fed state (in presence of insulin), LPL isozymes are regulated differently: LPL is upregulated in adipose LPL is downregulated in muscle Cardiac m. has > LPL than skeletal m. reflecting its prinicpal reliance on FA for energy In fasted state (absence of insulin) LPL is upregulated in muscle, by epinephrine LPL is downregulated in adipose *** LPL is extracellular and is anchored by heparan sulfate to the endothelial cell capillary walls. It is in the lumen of the capillaries 4. Depleted chylomicrons exchnage Apo C-II back to HDL 5. Apo E mediates reuptake of chylomicron remnants by the liver (chylomicron remnants are rich in cholesterol and cholesterol esters- uptake is by endocytosis) *** Type I Hyper-lipoproteinemia: results in accumulation of chylomicrons (chylomicron specific increases in lipoprotiens), can be caused by: - low LPL - apo C-II defect - inhibitors of LPL in the bloodstream

Rank the following in order from the one with highest [TAGs] to lowest

Chylomicrons> VLDL> IDL > LDL > HDL (2 and 3) NOTE: LDL has the highest [cholesterol esters]

As the stomach (foregut) rotates the GREATER omentum is formed from modification of the

DORSAL mesentery ** The Dorsal Mesentery extends all the length of the primitive gut tube that lies within the abdomino-pelvic cavity - with rotations of the foregut AND midgut the dorsal mesentery is modified and named according to the organs they connect

What is the fate of LDL after getting into the cell via receptor mediated endocytosis?

Degradation of LDL into AAs, phospholipids, fatty acids, and cholesterol - Degradation or recycling of receptor & the Cholesterol is- converted to esters by ACAT (AcylCoA: Cholesterol AcylTransferase- which transfers a fatty acid from acylCoA to cholesterol and makes an cholesteryl ester) for storage OR excreted in bile or as bile salts -------------------- LDL uptake and Reg. of Cholesterol Synthesis occurs in most cells - the liver typically synthesizes cholesterol to supply the body Synthesis and uptake is regulated via the following mechanisms: - cholesterol concentration through inhibition of HMG-CoA reductase - regulation of LDL receptors on the cell surface - regulation of LDL receptor synthesis NOTE: Cholesterol CANNOT be catabolized - it is lost by excretion - excess cholesterol can be excreted in the bile - some cholesterol is used for bile acid synthesis ** Most of the excreted bile salts are taken back up and returned to the liver - Gall stones occur when excess cholesterol is secreted into the bile and exceeds the capacity of the bile salts to keep it soluble - Compounds (resins) that bind bile acids can be used to prevent reabsorption in the intestine and lower uptake and thereby lower serum cholesterol by using it for synthesis of new bile salts

Diverticulum (aka Diverticulosis, Diverticular Disesase/ Diverticulitis)

Diverticulum: A sac-like protrusion of the colonic wall - Diverticulosis: defined by presence of diverticula, implies that the diverticuli are asymptomatic - diverticular disease= clinically significant and symptomatic diverticulosis ex. diverticular bleeding, diverticulitis, segmental colitis associated with diverticula- LLQ pain

Dietary DO's

Do Eat - a variety of veggies from all sugroups: dark green, red, orange, legumes (beans and peas), starchy, and others - fruits, especially whole fuirts - grains, at leadt hald of which are whole grains - fat-free or low-fat dairy, including milk, yogurt, cheese, and/or fortifies soy beverages - a variety of protein foods, including seafood, lean meats and poultry, eggs, legumes (beans and peas), and nuts, seeds, and soy products - oils - also: Exercise

Stool-softening Laxatives

Docusate and Mineral Oil MOA: - Docusate: surfactant that permits water and lipids to penetrate stool and retards water loss - Mineral oil: penetrates and softens stool and prevents water loss Pharmacokinetics: - oral and rectal - slow effect: 24-72hrs Adverse Effects: - Pneumonitis: aspiration of mineral oil - Impaired absorption of fat soluble vitamins: mineral oil - Anal leakage: mineral oil Clinical Use: - Constipation, minimize straining

Gastric emptying is the same thing as

Duodenal filling * if pressure in stomach > than duodenum then you open pylorus --> into the duodenum * if pressure in duodenum > than stomach then like in vomitting you flow from duodenum to stomach

The small intestine consists of

Duodenum (25cm): smallest portion - has forgut and midgut region (so has dual blood supply from celiac trunk and superior mesenteric artery - the first section of the SI after exiting the stomach- and it is the shortest, widest, most fixed part of the small colon - split into four parts: 1st part is intraperitoneal, 2nd-4th is retroperitoneal * duodenum is in close relation to the pancreas - fourth part of duodenum goes into the jejunum Jejunum (2.5m) Ileum (3.5m): longest portion

Development of cells of an ABNORMAL type within a tissue from cells of that tissue

Dysplasia - occurs in an environment of chronic inflammation, tissue damage and cell turnover - cells sustain damage to genetic and epigenetic material - repair in cells which survive is DEFECTIVE leading to altered genetic expression - cells become dysplastic and this may preced to metaplasia, which is also a form of altered genetic expression*** - clone of cells can evolve leading to malignant neoplasm (cancer) (anaplasia) *** Anaplasia= development of malignancy preceding dysplastic changes

In general, G cell secretion of gastrin stimulates

ECL cells and parietal cells

Stroke volume

EDV-ESV

Ejection fraction

EF= SV/EDV SV= EDV-ESV

What constitutes systemic hypertension?

Elevated: 120-129/ <80 Stage 1: 130-139/80-89 Stage 2: >140/90 ---------- Hypotension: a systolic BP of 90mmHG or less OR a diastolic of 60mmHg or less is generally considered to be indicative of hypotension

The function of bile is

Emulsion - Bile emulsifies lipids (soap action) - BIle, which has both lipid-soluble and water-soluble coponents, can facilitate a non-enzymatic breakdown of large fat droplets into many smaller ones, just like every other soap does- this functionally increase the surface area for which more lipase molecules/mL of fluid can interact with lipids - Facilitates digestion of lipids - Facilitates absorption of lipids ** by increasing surface area, more pancreatic lipases can be active at the same time (NOTE: Usually lipid-soluble substances tend to clump into formations that minimize surface area, and large globules of fat do this)- WITHOUT bile some lipids will be passed in stools

Describe the transition from Emulsion Droplets to Micelles

Emulsion droplets start with multiple membranes and a poor surface-to-volume ratio - In presence of BILE ACIDS, digestion from lipases hydrolyze TAGs and digested lipds "bud off" - The structures gradually transtion from a single emulsion droplet to some multilamellar vesicles, more unilamellar vesicles - and finally into many mixed micelles which collectively have a far greater surface-to-volume ration than had the original emulsion droplet ** One droplet: Poor surface/volume ratio ** Many micelles: great surface/volume ration, improves digestion

Ketogenic (low carb) diet

Ex: Atkins diet - focuses on low carbs and higher in fats, less so proteins - relies on tricking metabolism into having little to no insulin secretion - low insulin prevents body from going to anabolic state , promotes contant release of FAs from adipose- this promote ketogenesis Considerations: - ppl can exist and maintain a health lifestyle on this dieat - high fat can be concern for cholesterol - is under active reaserch for benefits and issues

The pancreas is an accessory gland of the digestive system which has both exocrine and endocrine function

Exocrine function: - production of digestive enzymes that are carried via the pancreatic duct to the duodenum - The exocrine pancreas is a tubuloacinar gland that produces daily ~1200ml of a bicarbonate-rich fluid containing digestive proenzymes (zymogens) and enzymes - 40-50 acinar cells form a round to oval acinus. The lumen of the acinus is occupied by 3-4 centroacinar cells, which form the beginning of the duct system ** the presence of centroacinar cells in the center of the acinus is a distinguishing characteristic of this gland Endocrine function: - release of hormones that regulate carb. metabolism - the endocrine portion of the pancreas is the islet of langerhans (l), are scattered among the exocrine portion (secretory acini) ** its flimsy CT capsule forms septa, which subdivide the gland into lobules

Ex. of a problem that can be caused by inflammation of the pancreas

Exocrine pancreatic insufficiency - an inability to secrete enough fluid (digestive enzymes) to properly digest the variety of nutrients in the small intestinal lumen - several causes include: cystic fibrosis and gallstone blockage of the pancreatic duct * 90% of pts with cystic fibrosis have failure of secretion of pancreatic enzymes into the duodenum - loss of CFTR function in cystic fibrosis results in reduction of ductular fluid and bicarbonate secretion - secretion not abolished completely bc some chloride is present in the acinar fluid- but this supply is small in comparison to that supplied via CFTR - thus pancreatic juice becomes viscous and sticky in cystic fibrosis leading eventually to plugging of pancreatic ducts- other secretory structures such as those in salivary glands, bile ducts, and pulmonary epihtelia are also affected, making this much more than just a GI disorder * bicarbonate (and fluid) secretion is heavily dependent on activity of the uniport, CFTR

In Data for improvement you should

Expect what you inspect - measure and monitor for desired and consistent outcomes

Types of Blood flow

F= change in pressure/ radius Laminar flow: ** concentric rings of equal flow rates - slowest flow occurs near the edge of the vessel due to friction - fastest flow occurs in the center of the vessel lumen ** the direct proportionality between BP and flow for a given vessel radius holds true, provided the flow is laminar Turbulent flow: - greatly impedes flow - req. an increased pressure to maintain flow - produces sound (cardiac auscultation) *** turbulence makes blood harder to move, requiring more pressure generation and a greater workload on the heart *** Reynolds (Re) number is a dimensonless index of tendency of flow to become turbulent: the higher the number the more likelihood of the flow being turbulent Re=vDp/n - turbulence is encouraged by a higher velocity of flow (v), a large diameter of vessel (D), and a high fluid density (p) as these factors increase fluid momentum- turbulence is LESS likely with high viscosit media (n)

T or F: phosphatidylglycerol is a MAJOR membrane constituent

FALSE! - but it is an important constituent of lung surfactant

T or F: the spermatic cord contains ALL the contents of the inguinal canal

FALSE! All contents of the inguinal canal include the spermatic cord- BUT the spermatic cord has its OWN contents (which DONT include all the contents of the inguinal canal) Spermatic Cord Contents Include: - Artery to ductus (vas) deferens - Ductus (vas) deferens - Lymphatics - Testicular artery - Cremasteris artery and vein - Remnant of Obliterated processus vaginalis - Pampiniform plexus of veins (right drains to IVC and left drains to Left renal vein) - Genital branch of genitofemoral nerve (GSE) Mnemonic: "All Doctors Love Taking Care Of Patients Genitals" *note: autonomic nerve fibers (GVE)- sympathetic innervation from para-aortic ganglion

T or F: Diff. hormones can induce secretion, and at times secretion can be zero

FALSE! it is true that diff. hormones can induce secretion BUT secretion is RARELY zero * Note that basal secretion of gastric juic is largely chief cell secretion

T or F: Chromium deficiencies are the most well understood

FALSE! its deficiencies and toxicities are NOT well understood or known, its actual requirements are not understood biochemically - it may be used in the insulin response? - it is found in all food groups

T or F: there are so many bacteria in the stomach

FALSE! there are actually very few almost close to zero and this is because the high acidity of the stomach which is antimicrobial -- The stomach is essential a pouch It has a Gastric Mucosal Barrier which includes: - mucus - pepsinogen - bicarbonate - hydrochloric acid ---- Stomach secretions of mucosal immunity can come from: G cells- gastrin secretion Parietal cells- hydrochloric acid (HCl) release Chief cells- pepsinogen release ------- Hyperchlorhydria (high HCl)- Zollinger-Ellison, Peptic Ulcer Disease) Hypochlorhydria (low HCl) Achlorhydria (NO HCl)

T or F: the Enterocyte pathway can reach the inductive site

FALSE! there is NO antigen to inductive site in the enterocyte pathway

T or F: the submucosa of the stomach has multiple glands

FALSE! NO glands here but it DOES have large blood vessels and nerves (Meissner's Plexus) "M's dont match"

T or F: Vitamin B4, Choline is a true vitamin

FALSE! VitB4, Choline is NOT a true vitamin because it is synthesized de novo - De novo synthesis is generally insufficient to supply daily needs (~550mg for men, 425mg for women) - principally req. for phosphatidyl choline in membrane, also the NT, Ach - also serves as a source of methyl groups fro S-adenosylmethionine (single -CH3 donor) *** formerly known as VitJ * In the USA, only 2% of postmenopausal women consume the recommended intake for choline

T or F: Most of the liquid of the GI tract is ingested

FALSE! it is NOT ingested but rather it is SECRETED - Digestive secretions contain most of the digestive enzymes that break down foods (ex. carbohydrates), again in that "external" space - Digestive secretions provide pH balance to intestinal contents and emulsidy lipids to maximize digestibility * gastrointestinal secretions include mucus for protection and lubrication -- these secretion help ensur border between outside of body lumens of the GI tract and the inside of the body behing the epithelial cells stays intact, and the materials in each "external" compartment are processed in the specific matter for whatever organ contains that compartment Ex: mouth, stomach, duodenum all have a diff pH and a diff set of digestive enzymes * digestive secretions make sure the ingested materials are processed in the most efficient way to ensure proper digestion and absorption

T or F: in mucosal immunity, inflammation is highly encouraged

FALSE!!! it is highly discouraged- and T regulatory cells are what aid in this

Layers of the gut tube include

FOUR layrers- common to the whole gut tube from esophagus to anal canal 1. Mucosa: epithelium, lamina propria and muscularis mucosae 2. Submucosa 3. Muscularis (can be 2-3 layers) 4. Serosa/ adventitia (called either/or depending on location *** ALL are derived from splanchnic mesoderm apart from the epithelial lining which is derived from endoderm

Which is absorbed fastest fructose, disaccharides, or TAGs

FRUCTOSE! like the fructose in high-fructose corn syrup can be absorbed as soon as it enters the duodenum, bc it req. NO digestion at all - other materials like disaccharides (ex. table sugar, sucrose) req. very little digestion and can also start having their component parts absorbed early rather than late - TAGs require more processing or multiple steps of enzymatic degradation before all their parts can be absorbed, and their absorption often starts in significant quantities in jejunum and still have some more absorption in the ileum **** other substances like cellulose (dietary fiber) CANNOT be digested by humans at all and are supposed to pass unchanged into the colon to help maintain the correct balance between solid and liquid in stools

Omphalocoele

Failure of intestinal loop to return to abd. cavity following physiological herniation - the diagnosis of omphalocele is usually made by ultrasound - presents in new-born as light grey, shiny sac protruding from the base of the umbilical cord - with omphalocoele, the size of the herniation can vary from small (containing only a portion of the SI) to very large (containing most of the abd. organs) --- A "Giant" Omphalocele is seen when the majority of the liver protrudes into the umbilical cord - Herniation of the fetal liver is frequently associated with a small abd. size and pulmonary hypoplasia (small lungs), two factors that can complicate the postnatal (after delivery) course - Fetuses with omphalocele are at an increased risk for other birth defect, such as cardiac or neural tube defects, intestinal malrotation and anomalies involving the urinary system Treatment: slowly push the intestines back into the abd cavity little by little

Double Aortic Arch

Failure of right doral aorta to regress CRANIAL to T4 Result: Double Aortic Arch and thus a vascular ring that can constrict the esophagus and trachea Sxs: difficulty swallowing and dysphagia

Short esophagus

Failure of the esophagus to elongate in proportion to development of the neck and thorax - Result: stomach displaced cranially into the thorax forming a congenital hiatal hernia

Pancreatic Juice is formed by two stages of secretory processes (similar to production of saliva). What is the first step?

First the acini produce a fluid that is isotonic to plasma and which has concentrations of Na+, K+, Cl-, HCO3- that are similar to ion concentrations in plasma - acinar cells also secrete the enzymes (often in an inactive form known as zymogens) that are vital to luminal digestion in the small intestine This fluid moves into the intercalated ductular system: which is connected to the acinus by the centroacinar cells - all parts of the ductular system are secretory - the ductal cells secrete a bicarbonate-rich fluid. A byproduct of bicarbonate secretion is chloride reabsorption - in contrast with salivary duct cells, fluids CAN move between pancreatic duct cells, because the junctions between them arent as tight as those in salivary glands *** the combined secretions of enzymes and sodium bicarbonate flows through the pancreatic duct that normally joins the hepatic duct immediately before it empties into the duodenum

"New Gastric Juice" composition varies with

Flow rate! Newly-secreted gastric juice just leaving the gastric pit consists of two distinct components: 1. Basal nonparietal-cell component: - at LOWEST flow rate (<0.2mL/min) - almost ALL chief cell secretion - little HCl secreted so is high in Na+ - relatively high Na+ and low H+ ** At lowest flow rates the stomach is usually empty except for "old" gastric juice already in lumen which strongly inhibits acid secretion since this old gastric juice is already extremely acidic- the other cells (chief, mucous) are not so strongly inhibited so the low flow of clear the gastric-pit gastric juice doesnt have very musch acid in it - pH is up, volume/min is down for lack of parietal cell secretion in the juice 2. Inducible parietal-cell component - FASTER flow rates (expecially >1mL/min) - largely parietal cell secretion - mostly HCl-rich fluid - relatively low Na+ and high H+ (low pH) ** With food in stomach, parietal cell secretion rises MUCH faster than chief or mucous cell secretion- parietal cell secretions have lots of HCl acid, much more than at low flow rates - pH drops as [H+ rises] ------ **** As flow rates change from basal to maximal flow, conc. of H+ in secreted fluid rises more than any other ion So when gastric secretion is maximal, pH of juice in gastric pit is very low, the better to re-acidify the main gastric lumen * since parietal cells dont secrete Na+, they dilute the Na+ in high-flow gastric juice * Intrinsic factor, a protein required for protection of VitB12 (cobalamin) from intestinal digestion is a parietal cell product- its secretion rises with gastric juice secretion

Why are laxatives used?

Fluid content is the principal determinant of stool volume and consistency. Motility also contributes to the process - decreased motility and reduced luminal fluid can lead to hardened and impacted stool which can result in constipation - Laxatives are used to treat constipation and for emptying the colon for clinical procedures Include: bulk-forming, stool softeners, osmotics and stimulants

Describe the fluid balance in the GI tract

Food brings in apprx. 2.0L/day via the mouth, esophagus - Inflow of saliva give 1.5L/day - Gastric secretion in the stomach gives 2.0L/day In SI: - Pancreatic secretion= 1.5L/day - Bile secretion= 0.5 L.day * these about are reabsorbed by the small intestine (duodenum at 6.5L/day): H2O, Na+, K+, Cl- - the Jejunum secretes 1L/day (HCO3-) this is presented to lumen of the small intestine (8.5L/day) - Not much occurs in the ileum - 2.0L/day are presented to the colon - the distal colon secretes K+ and HCO3- and 1.9L/day are reabsorbed by the colon (Na+, Cl-, H2O_ -- final ~0.1L/day are exreted in the feces via the anus -- REMEMBER - apprx 6.5-7 L/day of water are absorbed in small intestine - still leave 2L/day presented to the colon

Describe the sequence of carbohydrate digestion

For most carbs- digestion starts in the mouth with salivary amylase breaking down starch (luminal digestion by amylases (salivary & pancreatic)- this continues in the stomach until stomach acid renders these higher-pH enzymes inactive - Pancreatic amylase performs mostof the digestion of starch into smaller units, mostly maltose (disaccharide units) - These maltoses are broken down by maltase into two absorbable glucose molecules - the same process occurs for sucrose (using sucrase to produce glucose + fructose units) and lactose (converted by its enzyme lactase into glucose + galactose) ----- NOTE: there are indigestible carbs like cellulose which goes undigested by humans and is used as a physiological stool softener, providing a surface area with which water molecules can associate - adequate "dietary fiber" of this kind ensures that stools will not be too hard to easily pass (constipation) ---- NOT all humans express a functional lactase enzyme in adulthood- these ppl are susceptible to lactose intolerance in which bacteria complete the digestive process and in so doing produce acid, gas, and many osmotic components that result in diarrhea - lactase pills are sold in every pharmacy so this is a preventable condition

The esophagus is a ___ derivative

Foregut - therefore branches from celiac artery (via L gastric artery) which supply lower thoracic and abd portions of the esophagus HOWEVER - Cervical portion of the esophagus- supplied by branches of inferior thyroid artery - Middle portion of esophagus- supplied by esophageal branches from thoracic aorta

Formation of the Liver and Biliary Apparatus

Form from a ventral outgrowth of foregut at the end of week 3/beginning of week 4 - Outgrowth is termed hepatic diverticulum (liver bud) - Cranial portion- LIVER (will give rise to the liver initially) - Caudal portion just the BILE DUCT - Outgrowth from the bile duct gives rise to the gallbladder and cystic duct - Cystic duct will ultimately divide bile duct into hepatic duct and common bile duct ** Rotations of the foregut result in the entrance of bile duct moving from its anterior position to a posterior one, which results in the bile duct passing dorsal to the duodenum As growth of the liver bud continues the hepatic diverticulum it extends into the septum transversum - liver continuous to rapidly expand. Major fx is haematopoiesis in embryonic period (link physiological herniation of midgut) Eventually liver becomes too large to be contained within the septum transversum. Thus protrudes into the ventral mesentery, which is then modified to form - falciform ligament (attaches liver to body wall) - Lesser omentum (hepatogastric, hepatoduodenal ligament)

What is formed from the ventral mesentery (embryonic)

Form the adult mesentery - lesse omentum (hepatoduodenal and hepatogastric ligaments) - falciform ligament of liver - coronary ligament of liver - triangular ligament of liver

Apex of the Heart

Formed by the inferolateral part of the LEFT ventricle - where the SOUND of closure of the mitral valve is MAXIMAL - Lies along the mid-clavicular line deep to the left 5th intercostal space ** The point of maximal impulse ((PMI) apical pulse) is where the cardiac impulse can be BEST palpated on the chest wall - frequently this is at the LEFT 5th intercostal space at the mid-clavicular line

Lymphatic Ducts

Formed from convergence of lymphatic vessels Lymphatic ducts include: 1. thoraic duct 2. R lymphatic duct ** Ducts ultimately empty lymph into the blood stream

Formation of the primitive gut tube

Formed via craniocaudal and lateral folding of the embryo during weeks 3 and 4 of development The tri-laminar germ disc is thus transformed into an elongated cylinder of 3 concentric tubes: 1. outer ectoderm (not in region of umbilicus) 2. middle mesoderm 3. inner endoderm and the for-, mid- and hindgut are seen

Main storage chamber in the stomach is the

Fundus * most ingested food is stoed in fundus and proximal body NOTE: - when stomach smooth muscle contracts, pressure gradients form, promoting motility - the main mixing/grinding chamber of the stomach is the antrum - the body of the stomach has oxyntic glandular mucosa

Gastrin is produced by

G cells mostly in the antrum of the stomach ( a few G cells are in the duodenum as well) Main signal for secretion= Gastric lumen oligopeptides and AAs (pepsin digestion products) Minor signal: oligopeptides and AAs in duodenal lumen (G cells there) Pathway for action: Endocrine (secreted into blood for delivaary to target tissues) Main target tissues: Enterochromaffin-like cels (ECL cells) and parietal cells of gastric corpus Main actions: - increase gastric acid secretion, gastric motility Net effect: increase mechanical digestion and gastric emptying

Clinical uses for H2-Receptor Antagonists include

GERD and Peptic Ulcer Disease Prevention of bleeding from stress induced gastritis- critially ill patients: - Bleeding from upper GI erosions or ulcers occurs in 1-5% of critically ill patients as a result of impaired mucosal defense and poor perfusion **** Sometimes instead of H2 Receptor Antagonist Proton Pump Inhibitors are preferred for severe disease like erosive esophagitis and H. pylori related peptic ulcer disease

Inflammatory Disease of the gall bladder and biliary tree is commonly associated with the presence of

Gall Stones (lithiasis) Types: Acute Acalculous Cholecystitis: - associated with severe concurrent disease (trauma, surgery, burns, sepsis) Acute Calculous Cholecystitis: - obstruction of gallbladder neck or cystic duct (90%) Chronic Cholecystitis: - >90% associated with calculi (but not necessarily every time) - usually no preceding acute cholecystitis - fibrous thickening of the gallbladder wall - chronic inflammation (usually mild/moderate) - diverticula (Rokitansky-Aschoff sinuses)- show thickening of the wall of the gallbladder ** Classically seen with upper right abd pain, nausea, and intolerance to fatty foods >70% of individuals with gallstones are asymptomatic ------ Histology shows - usual pattern of acute inflamamtion: adema, leukocytic infiltration, vascular congestions, asbcess formation, or necrosis - when contained exudate is pure pus, the condition is referred to empyema of gallbladder

The surface of the stomach is subdivided by the

Gastric Pits - are funnel-shaped invaginations of the epithelium that are continuous at their base with the tubular glands - on the basis of differences in the types of glands present in the mucosa, 3 histological regions can be distinguished in the stomach: 1. Around cardia you find: cardiac glands * equal pits and glands 2. Fundus and corpus (body) contains: fundic glands * shallow pits, deep glands 3. Distal region of the stomach (pylorus) contains: pyloric glands * deep pits, shallow glands

Acid lipase is secreted by..

Gastric mucosa and acts in the lumen of the stomach

Peptic Ulcers can be either

Gastric or Duodenal * A peptic ulcer is a distinct leasion (or necrosis) of the mucosa in either the stomach, pyloric canal or duodenum as a result of acid erosin If they occur on: - Lesser curvature of stomach: can erode gastric artery - If on posterior wall of stomach: can erode splenic artery and the pancreas - If on anterior wall of the stomach: can erode the liver and cause peritonitis Sxs of peptic ulcers: - hematesmesis: vomiting "coffee ground" blood - melena: black, foul-smelling feces

Acid-peptic diseases include:

Gastroesophageal reflux disease (GERD), peptic ulcer disease (PUD) and Gastritis - therapies are directed at decreasing gastric aciditiy and promoting mucosal defense - the infectious agent Helicobacter pylori (H. Pylori) and the chronic use of nonsteroidal anti-inflammatory drugs (NSAIDs) play key role in the pathogenesis of acid-peptic diseases * NSAIDs can induce ulcers via inhibition of cyclooxygenase

Most common lysosomal storage disease

Gaucher Disease - accumulation of glucocerebrosides (the crumpled tissue paper appearance of the cytoplasm of Gaucher cells is caused by enlarge, elongated lysosomes filled with glucerebroside) - results in cognitive deterioration, demyelination - progressive paralysis and dementia in infantile form (type II) There are 3 types (all autosomal recessive) 1: most common and more freq. in Ashkenazi Jews- diagnosed in late 20s with mild decreased life expectancy- differentiator is having skeletal issus, increased bone breakage, sxs also include impaired olfaction and cognition 2: more sever form (shows up in infancy- mortality by age 3 typically) 3: only occurs in particular swedish population- mortality before age 30

Describe Parasympathetic stimulation of Saliva Composition

Generally - uses Ach and Muscarinic receptors at acinar cells - increases IP3/DAG/Calcium (Phospholipase C pathway) - increases fast flow of serous saliva, low viscocity high enzymes - more associated with food intake and processing * when PNS motor signals > SNS- you get low viscocity (thin) , relatively higher flow saliva output

Describe Sympathetic stimulation of Saliva Compositions

Generally - usues Norepinephrine and Beta receptors at acinar cells - increases cAMP (adenylyl cyclase pathway)- PKA etc. - produces slow flow of viscous saliva, high viscosity, high mucins - more associated with protection of oral cavity between meals ** if you need more mucus * when SNS motor signals > PNS - you get higher viscosity (thick, gooey), lower flow saliva output

Oral Rehydration Therapy

Give oral NaCl+ Glucose+ and H2O - increases absorption via 2Na+/Glucose SGLT1 symporter - reduces amount of diarrhea but it is still present

Which enzyme is deficient in Gaucher Disease?

Glucocerebrosidase (beta-glucosidase) - Glucocerebrosides accumulate in spleen, liver, lungs, bone marrow, and brain Sxs: hepatosplenomegaly in all types; mental retardation in types 2 and 3, skeletal disorders and anemia, in type 1 * can be done with enzyme replacement therapy or bone marrow transplant * this is th emost common lysosomal storage disorder * this is more common in Ashkanazi Jews * this is autosomal disorders

Major Membrane Lipid Types

Glycero-Phospholipids (MAJOR type AKA Phosphoglycerides)- usually unsaturated in middle with polar head group (zwitterionic) - Phosphatidylcholine (PC) - Phosphatidylserine (PS) - Phosphatidylethanolamine (PE) - Phosphatidylinositiol (PI)- key signaling one - Phosphatidylglycerol Sphingolipids - Pospho-Sphingolipids: sphingomyelin - Glyco-sphingolipids (sugar residues on outter leaflet) Cholesterol and Cholesterol esters (modulate fluidity) Other Lipids: - Cardiolipins - PAF - Plasmalogen *** large varity of lipids is reason why lipid membranes are amorphous (dont have highly regular repeating pattern) * also variety of distinct headgroups and glycolipids

Mucus secretions are produced by

Goblet cells These secretions - provide physical and chemical barriers - they are composed of mucins (glycoproteins) - contain antibody (sIgA)- (antimicrobial) - contain salt - trap microorganisms

Chylomicrons are assembled in the

Golgi of intestinal enterocytes (intestinal mucosal cells) - packaged into secretory vesicles - secreted into extracellular space - then travel through lymphatic system to the Left Subclavian Vein --------- Remember*: Chylomicrons have the - lowest density - largest size - highest % of lipids and lowest % proteins - highest TAG (dietary origin) - carry dietary lipids to peripheral tissues including: TAG, cholesterol, and fat soluble vitamins

Sources of Vit B9, Folate (formerly VitM)

Green leafy veggies, yeast, liver, some fruits Deficiency: Pregnant women, alcoholics MOST COMMON VIT DEFICIENY IN US ! - cossed by loss (pregnancy), inhibition by methotrexate, or poor absorption (alcholism, intestinal pathology) Sxs: Megaloblastic anemia (macrocytic- gets beggier w/o dividing) - Folate supplements help prevent Spina bifida (incomplete closure of the lumbar spine) and ananencephaly (absences of the brain), two common neural tube defects (these can happen before mother even knows, so recommended women of child bearing age- take supplements atleast 400microg/day) Sxs of deficiency include those of anemia: - lassitude and lethargy - feeling faint - headaches - pale skin - palpitations - irritability * can also include gray hair, mouth sores, tongue swelling and growth problems

HDLs life cycle

HDL is synthesized in the liver and intestines and also in the blood from secretion of ApoA-I - Nascent HDL is discoidal (flattened in shape, not spheroidal)- contains Apo A-I, Apo C-II, and ApoE (serves as reservoir for apo C-II and apoE)- exchanges these with VLDL and chylomicrons. Contains mostly phospholipids HDL takes up free cholesterol from peripheral tissues - form other lipoproteins and cell membranes by diffusion and transport proteins (ABCA1) ** defects in the ABCA1 protains can cause Tangier Disease - HDL is suitable for uptake of cholesterol because of high content of PC that both solubilizes cholesterol and acts as a source of fatty acid for cholesterol esterification Apo A-1 activates LCAT (lecithin: cholesterol acyl transferase) - LCAT makes cholesterol esters from free cholesterol and PC (phosphatidyl choline) - LCAT also produces lyso-PC as its other product - HDL stores the CE in its core Collection of CE matures nascent HDL to HDL3 - HDL3 collects cholesterol and matures further to HDL2 - HDL2 exchanges CE for TAG with VLDL (via the CETP (cholesteryl ester transfer protein: exchanges CE for TAG)) - This results in higher CE in VLDL and more TAG in HDL2 HDL2 drops off cholesterol and cholesterol esters and TAG to the liver: -HDL2 binds to SR-B1, a scavenger receptor -CE is taken up -Hepatic lipase degrades TAG for FA uptake -HDL2 is converted back to HDL3 * HDL3 returns to the circulation ----------- Main things: - transporter required for cholesterol to come out - LCAT req. to esterify the cholesterol and that activated by Apo-A

Intraperitoneal "within" organs are generally

HIGHLY mobile Defined as being almost ENTIRELY wrapped in visceral peritoneum - usually suspended by mesentery in the abd cavity ex: - liver - stomach - spleen - tail of pancreas - transverse colon - small intestine - jejunum - ileum - cecum and appendix - sigmoid colon - uterus - uterine tubes - half of rectum - first part of duodenum

Major regulated step (Rate Limiting Step) of cholesterol synthesis is

HMG CoA Reductase - Regulated principally by expression: Insulin (fed) upregulates it, glucagon/glucocorticoids (fasted) suppress it - Also regulated through phosphorylation: insulin dephosphorylates it to turn it on and AMPK phosphorylates it to turn it off (activated by glucagon) - Its expression is also inhibited by cholesterol **** This step determines if we will be high in cholesterol or not HMG CoA Reductase is a MAJOR drug target- it is competitivly inhibited by Statins **REMEMBER: Cholesterol is synthesized principally in the liver!

What is the rate limiting (regulated) step in cholesterol synthesis

HMG-CoA reductase - which converts HMG-CoA --> mevalonate * this enzyme is inhibited by STATINS (prescribed as cholesterol lowering drugs) * it is also reg. by feedback inhibition control --- Acetyl-CoA --> HMG-CoA --> Mevalonate ----->>>>Cholesterol

DHPs are used for

HTN without any compelling indication ** Nifedipine for ex. works mainly in vasodilation of peripheral arterioles and coronary arteries - does little in terms of contractility, SA node, and AV nod

What are some protective structures in the nasal cavity from pathogens:

Hairs: filter out particulates Nasal turbinates: create vortices to send particulates sticking to mucous Mucous: trap particulates *** the Mucociliary Escalator: traps microorganisms and dispells them- this escalator can be destroyed by many factors such as smoking or Cystic Fibrosis, also anesthesis, extreme cold etc.

Most common type of pancreatic cancer is cancer of the

Head of the Pancreas Tumor could obstruct: - Common bile duct - Hepatopancreatic ampulla * retention of bile pigments will lead to Jaundice--> can lead to stools/feces becoming acholic- Light/grey colored

Healthing after and MI

Healed/old MI, post-infarction scar - with sclerosis/fibrosis: replacement of necrotic myocardium with CT Complications in actue MI: Failure of cardiac (LV) pump function becuse of: - arrhythmias (ventricular fibrillation) - involvement of conduction system - contractile dysfunction (loss of cardiomyocytes) LV wall rupture with hemopericardium - cardiac tamponade **** so a MI with ruptu will lead to cardiac tomponade

HTN can have different affects depending on organ

Heart - can lead to LV hypertrophy, HF, risk fro ischemic heart disease Kidneys - renal failure Brain - stroke (cerebral infartion or hemorrhage) - (vascular) dementia Eye/retine - vision problems

Artherosclerosis can lead to acute ischemia or chronic ischemia

Heart--> MI (in acute)--> chronic ischemic heart disease Brain--> stroke (cerebral infart in acute)--> vascular dementia SI--> infarct --> ischemic intestinal disease Legs --> infarct (gangrene) --> intermittent claudication

Gastritis is most commonly caused by

Helicobacter Pylori - can be stained with a special Warthin-Starry/Giemsa stain (silver stain shows up) Gastritis will show acute inlammation of stomach mucosa: Histological images will show collection of inflammed cells in glands of the intestine of the stomach - You will also see infiltration of polymorphs (aka Neutrophils) and increase in chronic inflammatory cells (lymphocytes) which are reacting acutely to infection (NOTE: normally some of these chronic ones live in the stomach but the increase in infection)

Blood normally flows INTO the liver via the

Hepatic artery proper or the Hepatic Portal Vein

Heptaic vs. Gallbladder bile

Hepatic bile is a - yellow-green serous bile DIRECTLY from the liver - if you secrete enough it will work - the liver secrete apprx. 900 mL of hepatic bile/day of which 450 gets divereted to the gallbladder - this bile is usually quite high in ion/water content and relatively lower in organic content (ex. bilirubin and other bile pigments) and if it goes directly from here to the intestine (ex. right after a meal) then it is called hepatic bile Gallbladder bile is a - dark-green "concentrated" bile - this occurs between meals, the bile produced by hepatocytes is instead directed to the gallbladder for ion/water reabsorption and "concentration" of bile salts, pigments, and other organic components- bc colored bile pigments are more concentrated, gallbladder bile is much darker green bile - derived from hepatic bile, apprx. 50mL/day - osmotically similar to hepatic bile - fewer chloride ions, and typically more green bile acids (the soap) - you can secrete less volume to get the same effect on fat emulsification ** there is no good explanation as to why gallbladder bile has a lower pH than hepatic bile- it could be that there is carbonic anhydrase on the luminal side of the gallbladder apical membrnae but there is no proof for that *** the final bile (500mL/day) that reaches the duodenum secreted through the ampulla of Vater is typically a mixutre of more "dilute" bile and the more "concentrated" bile, modified by bile duct activity ***NOTE: bile salt make up about half the total solutes of gallbladder bile

R colic flexure is AKA as the

Hepatic flexure (associated with the liver) - turn between ascending to transverse colon

Venous drainage of the duodenum is ultimately to the

Hepatic portal vein --> Portal venous system (liver --> IVC --> R atrium) (the tributaries either drain directly or may first drain into the superior mesenteric/splenic veins)

Bile is secreted by

Hepatocytes ------ Sinsusoids (discontinuous capillaries) carry blood that can transfer very large molecules to or from hepatocytes - includes cholesterol, secondary bile acids, fat-soluble toxins, etc. Materials taken up into hepatocytes are processes into bile acids and other components of bile *** Bile is secreted into bile canaliculi and from here moves into interlobular --> septal --> lobar ducts and eventually R and L hepatic ducts (a pressure gradient is what drives this bile out)

When part of an organ is displaced and protrudes through the wall of the cavity containing it, often involving the intestine at a weak point in the abd wall

Herniation Types: - Umbilical hernia - Femoral hernia (more common in females) - Direct inguinal hernia - Indirect inguinal hernia - Incisional hernia (if area weakend after surgery) Can be: Acquired: pushes through the posterior wall of the inguinal canal or Congenital: moves trhough a patent (open) processus vaginalis (never closed during development)

_____ is located between the medial and lateral peritoneal (umbilical) folds and is a weak area in the posterior wall of the inguinal canal

Hesselbach's Inguinal Traingle Has 3 boundaries: 1. Medial border: lateral border of Rectus abdominis M. 2. Lateral border: Inferior epigastric vessels 3. Inferior border: inguinal ligamnet of Poupart Mnemonic: RIP (direct inguinal herni'a RIP through the triangle)

What enzyme is deficient in Sandhoff Disease?

Hexodaminidase A and B - GM2 and globosides in brain and other organs accumulate Sxs: severe form of Tay-Sachs (infantile), motor weakness, early blindness, marcocephaly, cherry red spot in eye, seizures * more severe than Tay-Sachs * autosomal recessive - hexosaminidase A has alpha and beta subunits as a heterodime and is lysosomal * mutation in alpha subunit gives rise to Tay-Sachs and affects only Hexosaminidase A * mutation in beta subunit affects both A and B- therefore this disease has sxs of Tay-Sachs including accumulation of GM2- with additional severe effects due to also missing Hexosaminidase B - hexosaminidase B is a beta subunit homodimer- exists elsewhere- physiological role not well understood

The overall volume of secretion of the exocrine pancreas on avg. is ~ same as that of salivary glands 1.5 L/day. When is the secretion rate of this at its highest?

Highest rates of secretion tend to occur when there is chyme from the stomach in the duodenum - the content of this chyme (ex. acids and lipid molecules) can be detected through chemoreceptors in the intestinal wall, leading to autonomic reflexes and pancreatic responses to hormones secreted by the intestinal wall (ex. secretin) *** failure of pancreatic exocrine secretions contributes to many pathologies of the digestive and endocrine systems

Formation of the IVC

Highly complex THe normal IVC is composed of 4 segments 1. Hepatic: derived from hepatocardiac channel (R vitelline vein) 2. Prerenal (suprarenal): derived from the R subcadinal vein 3. Renal: derived from subcardinal-supracardinal anastomoses 4. Postrenal (infrarenal): right supracardinal vein, although this idea is somewhat controversial

Septum formation in the atria

Highly complex process; commences at the end of week 4 The interarterial septum is formed by the fusion of 2 partial septa: 1. Septum primum: thin and membranous - Septum primium grows towards the endocardial cushions- as this happens the ostium primum is formed - the ostimu primum allows oxygenated blood to pass from right to left atrium BEFORE birth - Simultaneously endocardial cushions grow in atrioventricular (AV) region (dorsal and ventral cushions fuse to partition AV region into L and right canal) ** Just before the septum primum fuses with endocardial cushions apoptosis occurs in central portion to leave a new hole called the Ostium secundum 2. Septum secundum: thick and muscular - a thick muscular cresecentic membran grows to the right of the septum primum in a manner whereby the septum is incomplete ** Therefore it leaves an oval opening in caudal part= foramen ovale ** Septum primum functions as primitve valve= valve of foramen ovale ** NOTE in beginning: Large openings (foramina) in these two septa allowed right-to-left shunting of blood throughout development in utero

Distal Large Intestine Arterial Supply

Hindgut Derivatives: - Transverse colon (Distal 1/3rd), Descendign colon, Sigmoid Colon, Rectum & Anal Canal (above the pectinate line) Receive branches of the Inferior Mesenteric Artery: - Left Colic - Sigmoidal - Superior Rectal HOWEVER The proximal 2/3rds of the anal canal receive blood from Superior Rectal artery (terminal branch of the inferior mesenteric artery) ** Middle Rectal A. can come into play but it is NOT a branch of the inferior mesenteric artery it is from the Internal Iliac Artery (SO NOT all hindgut derivatives get blood supply from IMA)

The physical exam follows the

History --------- NOTE: In the case of an acute abd., the patients vital signs must be checked before proceeding to the abd examination - Pulse - BP - RR - Temp - SPO2 Abd Examination consists of (in this order) - Inspection - Ausculation - Percussion - Palpation

The Leadfrog Group are incharge of

Hospital rating and reports ** they are transparent with the public about what is going on in hospitals

Glycemic Load (GL)

How much the glucose concentration is raised by a typical serving of food - depends on carb content and glycemic index Formula= ( # grams of available cars in serving (portion) of food x Glycemic index )/ 100

What are 3 types of scrotal Defects

Hydrocele, Hematocele, Varicocele Hydrocele: - collection of serous fluid - may indicate inflammation of the epididymis - may be congenital and result from incomplete obliteration of processus vaginalis - translucent Hematocele: - collection of blood in tunic vaginalis - may indicate injury and rupture of the testicular artery - NOT transclucent Varicocele - dilated veins pampiniform ple us - common on the left - 90* drainage angle into L renal v. - Nutcracker syndrome - feels like a bundle of worms - usually disappears when lying down

Abnormalitis in Lipoprotein Metabolism include:

Hyperlipidemias - increases in lipids: TAGs or cholesterol - primary: genetic, congenital defect - secondary: Diabetes, Drug use (thiazides, beta blockers, estronges), Alcoholism, Hypothyroidism, Kidney failure, Nephrotic syndrome *** Arcus Senilis: cholesterol deposits in the corneal stroma. Though it occurs in pateints with familial hyperlipidemia, it is not predicitve for cardiovascular disease Hypercholesterolemias Cholesterol > 200mg/dl - Increased IDL, LDL, or HDL or some combination Caused by: - Diet (unclear how bad a diet is needed) - Obstructive jaundice - Hypothyroidism - Familial Hypercholesterolemia - Diabetes * REMEMBER a direct link between dietary cholesterol and increased risk for cardiovascular disease has not been firmly established- the most recent dietary guidelines from the US government provide a less stringent and more general limit on dietary cholesterol Hypertriglyceridemias > 150mg/dl of TAG - due to increased VLDL, or chylomicrons, or both

Inhibitors of slow waves of GI smooth muscle ______ the membrane

Hyperpolarize No contraction- flaccid smooth muscle- this is done by: - Norepinephine and Epinephrine (sympathetic) - VIP and NO (inhibitory parasympathetic neurons) - other GI hormones * hyperpolarizing a cell makes it less excitable

In the intestinal phase of pancreatic secretion: lipid and protein is detected by

I cells in duodenum which secrete CCK - CCK stimulates vagal reflex (ACh) and stimulates acinar secretion - ACh stimulates acinar and duct cells * remember CCK also worked in the gallbladder *** the pancres is NOT the gut wall, it has NO ENS. Vagal neurons directly interact with target cells in the pancreas -- NOTE the receptors on the luminal membrane of I cells that detect fat and protein in the duodenum. These cells secrete CCK into the blood, and into the local environment where CCK stimulates autonomic SENSORY cells. The autonomic reflex initiated by CCK causes a lot of acinar cell secretion using the PNS neurotransmitter ACh, and a lesser amount of stimulation of bicarbonate secretion from ducts. As fluid is secreted into the fixed-volume acinar lumen, its pressure will rise and this will force fluid out of the acinus toward the lower-pressure duodenal lumen

Cholecystokinin (CCK) is produced by

I cells, most of which are in the duodenum and jejunum Main signal for secretion= fatty acids in duodenal/jejunal lumen Minor signal: oligopeptides and AAs in duodenal lumen Pathway for action: Endocrine (secreted into blood for delivery to target tissues), Indirect effects via ANS (Vagus) Main target tissues: ANS sensory neurons, gallbladder smooth muscle, pancreatic acinar cells, parietal cells? Main actions: Stimulate gallbladder contraction (direct), bile secretion; Reduce gastric emptying; inhibit Gastrins stimulation of acid secretion

Conjenital Thoracic Wall Deformities inclue

I. Pectus Excavatum - CONCAVE depression "sunken chest" - Causes: intrauterin pressure on the chest wall during development - Complication: compression of heart and lungs - Treatment: surgery II.Pectus Carinatum - PROTRUSION of the sternum and costal cartilages "Pigeon Chest" - Causes: Scoliosis and Congenital Heart Disease - Treatment: 1st line of treatment is brace worn around the chest and provides pressure from both the front and back to move the breastbone back to its usual position. The child wears the brace for up to 24hrs a day, for a period of months to years - Surgery is an alternative treatment if the brace does not work

Phosphatidyl inositol and phosphatidyl serine are found in the

INNER leaflet in contact in the cytosol ** when PS is found on the outter leaflet it is an apoptotic signal

Palpation and the Clinical Finding of Rigidity

INVOLUNTARY, reflex muscle spasm is caused by peritoneal irritation - it persists despite relaxing or distracting maneuvers - pain occurs when abd wall contracts (the pt attempts a sit-up without using arms, lifts head off the bed) - reflex rigidity may be unilateral and localized - symmetry is assessed by evaulating muscle tensness on each side comparing right to life in upper and lower quadrants

Orthostatic Hypotension

If a person is hypovolemic or has an impaired baroreceptor reflex: - BP is NOT rapidly returned to normal when changing body position - syncope may occur *** orthostatic hypotension= inability to restore BP to normal with a change in body position ** tilt table test is used to detec reasons for orthostatic hypotension ------ This shift in blood volume to LE decreases thoracic venous blood volume and therefore CVP decreases ----- in absence of a functional baroreceptor- changing from supine to standing position (orthostasis) involves: ** decrease vagal outflow of the heart and increased symp cardiac and vasomotor nerves - increase venous volume, heart rate, contractility - decrease intrathoracic blood volume, stroke volume, MAP, and cerebral perfusion (can lead to syncope/fainting) ** overall MAP increases by 10-15 mmHg above supine level BUT this does not occur in normal individual if their baroreceptor reflex is fully functional

Irreversible shock

If decompensated shock contrinues without treatment, or the blood loss is greater than 20%, irreversible sjock can result - this CANNOT be corrected - it causes further deterioration of several systems: circulatory, endocrine, CNS ** ultimately results in organ damage and death ** phase of hypovolemic shock

Marks the junction between the SI and the LI

Ileocecal Junction - when the ileum empties content into the cecum via the ileocecal valve the Ileocecal valve is: - superior and inferior ileocolic lips - formed by two semilunar (half-moon shaped) flaps that surrounds a slit-like orifice (hole)- come together to form Frenulum of the ileocecal valve - located apprx. 2cm above the opening of the appendix * acts to prevent reflux of chyme from the cecum back into the ileum when digested material is acting against gravity to be propelled up the ascending colon

Lymphoid tissues (BALT, NALT, SALT, GALT, MALT) at the respiratory tract can act as

Immune inductive sites - where an antigen is concentrated and presented to T cells and effective T cells are generated ** BALTE= bronchial associate lymphoid tissues

Describe the mechanism of Amino Acid and Peptide Absorption

In digestion of proteins and oligopeptides, the usual products that reach the apical membranes of enterocytes are single amino acids, dipeptides, and tripeptides - Unlike with carbs, it is not necessary to digest the trimers and dimers before absorption across the apical membrane, because there is a transporter, PepT1 (that with hydrogen as a cotransporter can carry these into the cell for final digestion inside the enterocyte) * the peptide dimers and trimers will compete for this transporter -------- This above occurs at the duodenal and jejunal lumen - NOTE that singl amino acids use Na+ cotransport to get across the apical membrane and that there is a Na+/H+ antiport on apical membrane which allows there to be H+ present for the PepT1 transporter to get either Dipeptide or tripeptides into the cells - if coming in via PepT1 the peptides are further digested (stops at secondary lysosome?), if through the Na+ cotransport it goes straight- but either way once AAs they go out through the basolateral ECF - NOTE: that K+ also comes out of basolateral ECF and there is also a Na+/K+ ATPase

Canal of Nuck

In females - if there is an incomplete obliteration of the processus vaginalis in females, this can lead to formation of a small abnormal pouch of peritoneum in the inguinal canal - the pouch extends anterior to the round ligament of the uterus and travel into the lavia majora - analogous to a patent processus vaginalis in males and can result in either: indirect inguinal hernia, hydrocele, or cyst ex: hydrocele locates along the L round ligament and extending towards the labium majus

Acrodermatitis Enteropathica

Inborn error (rare) with inability to absorb Zinc (Zn) - Results in skin inflammation with pimple (pustular dermatitis), diarrhea, abnormal nails - Acquired form can result from prepared nutritional programs - A mutation of the SLC39A gene on chromosome 8 is responsible for the inborn disorder *** this is curable with oral zinc supplements or zinc injection- symptoms will clear

Hindgut Development

Includes: Transverse colon (distal 1/3rd), Descending colon, Sigmoid colon, Rectum & Anal Canal (above pectinate line) - Terminal end of hindgut is an endodermal-lined pouch called the cloaca - in contact with surface ectoderm of proctodeum to form the cloacal membrane - The Cloaca is partitioned by urorectal septum (mesoderm) into rectum, upper anal canal and urogenital sinus - Cloacal membrane is partitioned to form anal membrane and urogenital membrane ** Urorectal septum fuses with the cloacal membrane at future site of the Perineal Body (an important landmark in external genitalia)

If MAP increases: Then Output from the nucleus ambiguus and Dorsal motor nucleus of the vagus, activity of the carotid sinus afferents, excitatory input into the nucleu ambiguus, afferent activity of 9th and 10th CNs, activity of glossopharyngeal afferens, vagal innervation of the SA node all increase or decrease?

Increase!

Acyanotic Congenital Heart Diseases can be due to

Increased pulmonary blood flow - Atrial Septal Defect - Ventricular Septal Defect - Patent Ductus arteriosus - Atriventricular canal orrr Obstruction to blood flow from ventricles - Coarctation of aorta - Aortic stenosis - Pulmonic Stenosis

PV loop changes in exercise

Increased: - EDV (decreased venous compliance, increased VR) - systeolic BP (increased symp drive to vent. tissue and increased contractility) - increased SV (EDV-ESV), HR, CO - stroke work (area of the PV loop) *** ESPVR line steeper Decreased: - ESV (increased contractility, increased ejection fraction)

Preload (load on ventricle BEFORE contraction has started) can be

Increases (volume overload) - aortic regurgitaion, mitral regurgitaion, left-to-right shunts Reduced preload by Reduced compliance (=increased stiffness) - reduced structures compliance Ex. with LV hypertrophy in HTN, sub-aortic hypertrophy - reduced functional compliance: impaired relaxation in acute ischemia Compression from outside ex. cadiac tomponade by fluis accumulated in pericardial sac

Indirect vs. Direct Inguinal Hernia

Indirect Inguinal Hernia - LATERAL to inferior epigastric artery - orginates from the DEEP inguinal ring (technically there is no defect as this opening is already transmitting the ductus deferens or round ligament of the uterus) - travels through all of the inguinal canal - emerges from superficial inguinal ring (like direct inguinal hernia) - herniated content is covered by all 3 layers of spermatic cord plus peritoneum (easier to fully enter the scrotum) * More common in young males * congenital Direct Inguinal Hernia - MEDIAL to inferior epigastric artery - originates from HESSELBACH'S TRIANGLE (takes a dramatic shortcut - pushes through weak area) - travels through MEDIAL part of the inguinal canal - emerges from superficial inguinal ring (just like indirect inguinal hernia) - herniated content is ONLY covered by transversalis fascia and parietal peritoneum (less likely to fully enter the scrotum * more common in older males * acquired

Superior Epigastric aa. anastomose with the

Inferior Epigastric aa. around the umbilicus

Superior Mesenteric A. which supplies the midgut has 5 branches which are:

Inferior Pancreaticoduodenal Artery Intestinal Arteries - give rise to vasa rectae (aka arteriae rectae) Middle Colic Artery - forms part of Marginal Artery of Drummond Right Colic Artery Ileocolic Artery - gives off Appendicular Artery ----- NOTE: Parasymp. Innervation to Midgut via Vagus Nerves (CNX) Symp. Innervation via Thoracic splanchnic nerves (T9-T12) for pre-ganglionics and Superior Mesenteric Ganglion via post-ganglionic cell bodies

Double IVC

Inferior portion of the L supracardinal vein persists - they may significant asymmetry in the sized of the L and R veins MOST COMMON: - Left IVC typically ends at the L renal vein, which crosses anterior to the aorta in the noraml fashion to join the right IVC

Palpation & Clinical Finding of Reboud Tenderness

Inflamed peritoneum is painful with direct pressure or movement, especially when two inflammed surfaces slide over one another - the peritoneum has somatic sensory afferents and the site of pain is well localized - rebound tenderness is reliable sign of peritoneal inflammation Techniques: - press the fingertips gently into the abd, then suddenly withdraw them - pain worsened after withdrawal is rebound tenderness - alternate and less painful method uses light percussion or asking the patient to cough both of which worsen pain If an abd mass is permeable, determine: - size - depends on the character - shape - borders defined or not -consistency (hard, firm, soft) - location - presence of absence of pulsation - tender vs. non-tender - surface: smooth or irregular - Mobility (mass arising from intestine that is anchored by a mesentery is very mobile, mass attached to the inferior surface of the diaphragm moves with respiration NOTE: if mass origiantes/is arising from the pelvis (ex. uterine tumor), the lower margin will not be palpable

The inguinal canal is found in the

Inguinal region of the abdominal wall: which is the area between the anterior superior iliac spine (ASIS) and the pubic tubercle * the inguinal canal is a passageway from the abd cavity through the anterior abd wall NOTE: the inguinal canal is formed by fold of the EXTERNAL ABDOMINAL OBLIQUE APONEUROSIS - these folds then form 2 rings: external/superficial inguinal ring and the Internal/deep inguinal ring * this inguinal canal transports important contents and has specific boundaries Contents of the inguinal canal: - spermatic cord (M) - roung ligament of uterus (F) - inguinal nerve - blood and lymphatic vessels ** the inguinal canal has an entrance and exit: it starts DEEP and lateral to the inferior epigastric artery and goes through the anterior abd wall traveling anteriorly and exits more medial and superficial and the superficial/external inguinal ring

Familial Adenomatous Polyposis (FAP)

Inheritance: - mutation of the tumor suppressor gene APC (adenomatous polyposis coli) - autosomal dominant (positive family history) - up to 25% of cases have a negative family history Epidemiology: - 1/10,000-30,000 live births - <1% of colorectal cancers in US are due to FAP - both sexes equally affected - Polyposis typically develops within the third decade of life Clinical features: - most are intially ASYMPTOMATIC until progresssing to colon cancer - altered bowel habits (constipation/diarrhea), blood in stool, and abd pain ** Colonic polyps can be benign --> then show sxs of dysplasia --> and can evolve into colonic adenocarcinoma (where cells and tisse have little resemblance to normal tissue, necrosis and invasion of local tissues and metastisis are persent)

Patient Care vs. System Care

Initial Work up: - Individual pt: chart review, history, PE - System: identification of error, experience in the system, feedback about the system Further Work up: - Individual pt: blood work, other lab tests, imaging studies, functional tests - System: observation of the process, process analysis/modeling, review of outcomes data Therapy/Treatment: - Individual pt: Medication, surgery, watchful waiting - System: apply model for improvement, perform root cause analysis, perform PDSA cycles

Where would you find pain in acute appendicitis vs. initial appendicitis

Initial: periumbilical pain - affects GVA axons Acute: McBurney's point pain (1/3rd between the ASIS and the umbilicus) - affects GSA axons

Endocardium of the heart

Inner most layer which faces the heart chamber Consists of: 1. Inner thin endothelial layer (simple squamous epithelium) - endothelial cells sit on subendothelium CT 2. Middle myoelastic layer - consists of smooth muscle and CT tissue 3. Deep subendocardial layer - merges with the outer myocardium Consists of: - CT - Blood vessels - Purkinje Fiber (important in conducting system of the heart)

Thoracocentesis/ Thoracocentesis/ Pleural tap

Inserting a needle into the pleural cavity to obtain a sample of fluids - Needle is inserted midway within the intercostal spaces to avoid damagin the nerves (intercostals and collateral branches) - The needles is angled UPWARD to avoid injuring the diaphragmatic pleura and the diaphragm ** When pt is in upright position, fluid acucmulates in the costadiaphragmatic recess ** INSERTING THE NEEDLE INTO 8th/9th INTERCOSTAL SPACE MIDAXILLAR LINE during EXPIRATION WILL AVOID THE INFERIOR BORDER OF THE LUNG

What are two motility patterns in the small intestine?

Interdigestive (fasting) state: - No nutrients in the lumen (fasting- pylorus can relax all the way to let something through) - Pattern of motility: 90-120 minute pattern of virtually no activity followed by short intense peristalsis of non-nutrients in a CAUDAL direction - Wave of contraction that sweeps materials is called the Migrating Motor Complex (MMC, also called migrating myoelectric complex) - Feeding terminates this state and the MMCs with it Digestive (fed) state: - nurtients are in the lumen - Pattern of motility: many segmental contractions (churning movements) to facilitate digestion/absorption of luminal contents with some peristalsis for propulsive movement of luminal contents in a caudal direction ** If occuring shortly after a meal is taken in, digested, and then absorbed this is called the postabsorptive state. Its counterpart, the digestive (fed) state, is also known as the absorptive state

Emptying of the rectum deals with 2 sphincters

Internal Anal Sphincter (autonomic, involuntary) - passive rectal distention triggers relaxation of smooth muscle of IAS (rectosphincteric reflex)- enough distension allows relaxation External Anal Sphincter (voluntary) - if defecation not desired, the skeletal m. of external anal sphincter contracts -------------- Due to the proximity of the rectum to the IAS, the rectosphincteric reflex is an ex. of a reflex that can occur by the ENS alone. The ANS is usually involved and with the EAS role, the somatic NS as well ---- When conscious decision is made to open the EAS, the last resistance point for solid waste passage is gone. Accompanying this proccess is secretion of mucus along the length of the rectum and anal canal, to reduce friction and further facilitate defecation - if that STILL isnt enough to force fecal material out of the body, deliberately increasing abdpelvic pressure by straining (the Valsalva maneuver) can often overcome the final resistance and allow passage of even very solid fecal masses.

Slow waves are generated in the

Interstitial Cells of Cajal - slow waves are then conducted to smooth muscle cells via L-type Ca++ action potential mechanim - soo if the membranes threshold -38mV and you dont ever hit this threshold you will still get some contraction without an action potential bc you have calicum working with calmodulin * As you control ICCs you can control membranes of muscle cells, make them more or less excitable- hyperpolarize (less excitable), depolarize (more excitable) * rate 10-12/min, normal for slow wavse in the duodenum

What are some specialized lymphocytes that can be found in mucosal immunity?

Intraepithelial lymphocytes (mainly CD8+) these are found within the gut associated lymphoid tissue - they may express gamma-delta TCR (NOTE: that most T cells are usually alpha-beta) - these are considered INNATE T cells! (by definition T cells are usually adaptive but here they act as innate) - since they are INNATE they require NO priming and can respond spontaneously to challenge and release cytokines and kill infected cells using perforin and FasL (like NK cells) ------- so big point: Intraepithelial cells are INNATE T cells, expressed GAMMA-DELTA TCR, and do NOT require priming all these things make them a specialized lymphocyte ---- Steps: 1. virus infects mucosal epithelium cells 2. infected cell displays viral peptide to CD8 IEL via MHC class I 3. activated IEL kills infected epithelial cell by perforin/granzyme and Fas-dependent pathways

Biliary Atresia can be

Intrahepatic (very rare 1:100,000)- duct in liver blocked or Extrahepatic (1/10,000) MORE COMMON - extrahepatic is atresia of an extrahepatic duct such as the hepatic duct or bile duct - incomplete recanalization (postnatally infection) - jaundice - if cannot be treated surgically- you will need a liver transplant, if not will be fatal ** this can be a reason for why a newborn male passes pale meconium (could be a problem with his hepatocytes)

What are two types of control of the Enteric Nervous System (ENS)

Intrinsic: the control 100% mediated by ENS from sensor to motor - "short loop": the reflex stays in the gut the whole time (starts and ends in gut tube * most feflexes are intrinsic) and Extrinsic: ANS involved (PNS and SNS involved- stimulating or suppressing ENS motor neuron reflexes) - modulates ENS action - can completely override ENS action - "long loop": the reflex goes to CNS control centers and back - parasympathetic modulating/override is almost always at the plexus level - sympathetic modulation is mostly at the plexus level- the modulation also involved direct but limited innervation of gut smooth m., mucosal cells, and blood vessels

Hematochromatosis is aka

Iron Overload - Cumulative (10-40g excess, 2.5g is typical (male)) - More prevelant in OLDER men, from northern Europe *** is exacerbated by mutations in HFE gene, which senses iron in the liver - Affects liver, heart, and endocrine glands - Presents with Cirrhosis, Diabetes, Cardiomyopathy, and arthritis *** How does anemia caused by iron deficiency compare to that caused by folate or VitB12 deficiency? What is key distinguishing feature?

Driving pressure

Is the change in pressure: P1-P2 (pressure difference along the length of the vessel) - it is responsible for blood flow Driving presure of systemic circulatory system: - P1= aorta (120/80mmHg) - P2= right atirum (-4-4 mmHg) *** pressure in systemic blood vessels falls continuously from the aorta until the blood re-enters the heart in the RA **In systemic circulation it driving pressure is effectively the same as MAP as RA pressure is so low giving the equation: MAP=COxTPR Driving pressure of the pulmonary circulatory system: - P1= pulmonary artery (25/8mmHg) - P2= LA (6-12mmHg) ** Pulmonary Vascular Resistance (PVR)= Mean Pulmonary Artery pressure (MPAP)- Pulmonary Wedge pressure (PWP)/CO

What is the issue with excess use of antibiotics on the normal flora of the body

It destroys the normal flora which may lead to disease due to growth of opportunisitc organsims ex. increased clostridium difficile growth - this growth and toxin production can lead to diarrhea and Pseudomembranous Enterocolitis *** which is a classic disease of antibiotics another infection that can occur is Candidiasis

What is the role of iron in the body?

It is present in many proteins as part of hemes - hemes: Hb, Myoglobin, Cytochromes - iron-sulfur clusters; redox centers in electron transport * can switch between ferrous (Fe2+) and ferric (Fe3+) states to facilitate reduction/oxidation and electron transfer Recommended iron intake: 8-18mg daily (8 for males, 18 for females bc menstrual cycle etc.) Absorption and distribution is TIGHTLY regulated - free (unbound or unchelated) iron is dangerous due to catalyzing free radical formation

Describe the biological defense of mucosal immunity for GU?

It is provided by resident macrophages and cytokine-recruited immune cells: - macrophages - dendritic cells - specialized NK cells - neutrophils - B cells (sIgA) - T cells

Describe the muscularis externa of the esophagus

It is subdivided into: - upper (entirely skeletal m. in muscularis externa)- allows voluntary completion of swallowing (an inner circular muscle and outer longitudinal muscle) - middle (mixed smooth and skeletal mucle) - lower (entirely smooth muscle) portions- controlled via ENS --- * remember pharynx was 100% skeletal muscle- continous with esophagus (upper 1/3rd of esophagus is skeletal muscle)

Mitral Valve Insufficiency

Mitral Valve leaflets disorder - Blood regurgitates into the left atrium - A Dilated Left Atrium is likely to compress the esophagus= dysphagia ** also tumors in the Left Atrium can compress the esophagus and thoracic aorta

Causes of Acute Pancreatitis

Mnemonic: I GET SMASHED - Idiopathic - Gall Stones - 2nd most common cause in US - Ethanol (alcohol)- MOST COMMON CAUSE in US - Trauma - Steroids - Mumps/Malignancy - Autoimune (may have IgG4 antibody present) - Scorpion stings - Hypercalcemia/Hypertriglyceridemia (TG>1000) - ERCP - Drugs (ex. HCTZ, Didanosine, Pentamidine, Bactrim, Azathioprine)

Congenital Umbilical Hernia

More common in premature births - occuring twice as commonly in boys than girls (not known why) - intestines return into body BUT musculature of ventral abd wall DOES NOT close umbilical ring-- Bowel protrudes (covered by skin) through the linea alba and transversalis fascia - if these hernia are asymptomatic, reducible, and dont enlarge, no surgery is needed (in other cases it must be considered) ** Umbilical hernias usually resolve spontaneously by the time the child is 2 yrs old, so do not usually require any treatment

Describe the activity of the Migratory Motor Complex (MMC aka Migrating Myoelectic Complex) in the Interdigestive (fasting) period (no nutrients) in the small intestine:

It starts in the proximal stomach - For any one location, each wave typically lasts 90-120 minutes, in four phases Phase 1: Quiescent, little activity (normal) - very flat and hyperpolarized slow waves, rarely achieving even a singl action potential- this is by far the longest part of the whole 90-120 minute process Phase 2: Increasing activity - a gradual period in which inhibition of slow waves end, resulting in small, weak waves that provide little pressure for movement of non-food material (ex. Nonnitritive fiber) in the lumens. Towards the end of this phase a hormone called Motilin starts to rise. Phase 3: Peak electrical and mechanical activity - Under heavy influence of motilin, a period of very strong, very amplified rise and fall of membrane potential, resulting in many action potentials that summate, producing very powerful muscle contraction. This phase rarely lasts more than 15 minutes and is often shorter <10min. The pace of the waves is unchanged but their magnitude is so much greater that there is a sizble muscular response Phase 4: Declining activity, transitioning into quiescence - Reset period, during which the motilin effect ends and the contractions become weaker until the slow waves are once again greatly inhibited resulting in little to no muscle contraction (phase 1) - this phase is quite short, only a few minutes Result: Periodic strong waves of contractions sweeping from stomach to terminal ileum ------------- Different than the: Digestive period (fed state) which has relatively constant activity once nutrients arrive, until they are all absorbed. Churning and propulsion occur

Anemia- Iron Insufficieny

More common in women, women have higher dietary requirements for iron - deficiency impairs Hb synthesis and causes MICROCYTIC hypochromic anemia: Pallow, weakness, lassitude - Can be caused by massive hemorrhage, chronic blood loss such as menstruation, growth or pregnancy Severe anemia: - fainting - chest pain - angina - heart attack

Jejunum and Ileum receive their arterial supply from the

Jejunal and Ileal arteries from the Superior Mesenteric Artery Venous drainage: Ultimately to hepatic portal vein --> portal venous system via the SMV Lymphatics: ultimately drain by following the arteries towards--> Superior Mesenteric Lymph nodes ** One of the only ones we have seen that DONT drain to celiac lymph nodes Innervation: Parasympathetic --> Vagus (CNX) Sympathetic --> Greater Splanchnic (T5-T9) and Lesser Splanchnic Nerves (T10-T11)

GIP (in past called gastic inhibitory peptide) and (now called Glucose-dependent insulinotropic peptide) is produced by

K cells in the duodenum and jejunum (K cells are connected to the outside of the body- they are detecting ANY kind of major food) Main signal for secretion: glucose, AA, fatty acids in intestinal lumen Pathway of action: Endocrine (secreted into blood for delivary to target tissues) Main target tissues: Pancreatic Islets (beta cells- endocrine), Parietal cells, G cells Main actions: potentiate insulin secretion (incretin effect- make insulin secretion bigger than normal) Inhibit gastric motility, inhibit gastric secretion (minor effect) * if already have nutrients on SI tells beta cells to be ready when glucose absorbed to secrete insulin (incretin effect)

Cardiac Ion channels for K+

K+ currents are OUTWARD and make the cell more negative inside when they flow (repolarization) There are 4 different K+ channels (i.e. 4 diff gene products) in cardiac muscle which allow outward K+ current to flow at various times duing the action potential (AP) 1. Inward rectifier (Kir 2.1) - acts as a background K+ channel - this channel opens at negative membrane potentials and sets the stable negative resting membrane potential of atrial and ventricular muscle close to the Nernst Potential for potassium- as membrane potential becomes more postiive these channels shut 2. Transient outward K+ current (Ito) - opens rapidly upon depolarization of the membrane but closes quite rapidly too so generates a transient repolarizing force in ventricular and atrial muscle 3. Rapid component of delayed rectifier K+ current: IKr 4. Slow component of delayed rectifier K+ current: IKs ** These Delayed Rectifier K+ Channels (IKr and IKs) are closed at negative voltages - they open when membrane potential becomes more positive and so these channels are mainly responsible for the repolzarization of action potentials in the heart - IKr (which activates quite slowly, hence the term delayed) is so termed because it has a faster inactivation rate than IKs - The IKr current is larger than IKs and so is the more important current in facilitating repolarization of action potentials

List differences between the Dietary protein Deficiences Kwashiorkor and Marsmus

Kwashiorkor: - weight is 60-80% for expected age - weight for heigh could be normal or decreased - edema is PRESENT - pt is irritable when picked up; apathetic when left alone - POOR appetitie Marasmus - weight for age <60% for age - weight for height is markedly decreased - edema is ABSENT - pt is alert, irritable - GOOD appetitie

Dorsally the aortic arch artries conect to the

L and R dorsal aortae - Dorsal aortae remain separate in the region of the aortic arch arteries - they fuse together from T4-L4 to form the descending aorta- which can be further "subdivided" into thoracic and abd aorta NOTE: in formation of arterial system (aortic arch arteries)- 5 paires arteries develop in associated with the pharyngeal/branchial arches

L sided vs R sided heart fialure

L side: accumulation of blood in pulmonary circuit - pulmonary edema and pleural effusions R side: accumulation of blood in the venous compartment of the systemic circulation - distension of jugular veins (SVC) - peripheral edema- dependent areas - peritoneal effusion (aka ascites) - visceral organ congestion: liver, spleen, intestines ** pitting edema and ascites common

Lsided vs R sided heart failure

L sided heart failure: Due to failure of LV Can be systolic or diastolic dysfunction Leads to: - decreased CO - increased pulmonary volume and pulmonary capillary pressure - pulmonary edema - LA enlargement - Right heart fialure R sided heart faiure: Due to failure of RV can be systolic or diastolic dysfunction Leads to: - decreased pulmonary volume, left heart volumes, CO - increased systemi capillary hydrostatic pressure - peripheral edema - RA enlargement - elevated jugular venous pulse pressure *** CVP is increased which leads to increased systemic capillary hydrostatic pressure and peripheral edema

L ventricular vs. R ventricular coronary flow

L ventricular coronary flow is highest during diastole - intiial arterial compression during systole decrease LV coronary flow ** blood flow through vessels is greatly reduced during systeole due to compression of the vessels during ventricular contraction ** most blood flow during diastol bc ventricular muscle is relaxed and coronary vessels are unobstructed (** Windkessel effect) - R ventricular coronary flow does not decreased initilay during systole as less compression occurs ----------------- Bc LV muscle contracts w high force, during systole -- this leads to increased metabolix waste produce which induce vasodilation so blood flow duirng systole increase (active hyperemia) During diastole when LV muscle is relaxed, coronary vessels are opened and coronary flow increases as result of reactive hyperemia ----- R coronary flow increasses during systole bd coronary artery pressure risses during systole and increase driving pressure increases R coronary blood flow -- this is why there is much reduced reactive hyperemia component in the R coronary arteries compared to the L coronary arteries

Calcium Channel Blockers (CCBs) inhibit the

L-type calcium channels (here they inhibit Ca2+ influx) - Affects the contractilie tissue (vascular smooth m. in peipheral and cardiac arterioles) and cardiac myocytoes --> Ca2+ role in contractility - Conduction system; SA and AV nodes (affect depolarization)--> Ca2+ role in chronotropy, ionotropy, and dromotropy ---------- Positive Chronotrope: increases HR (typically of SA node) Positive Dromotrope: increases conduction speed (typically signal through AV node) Positive inotrope: increases contractility (typically myocyte)

Main effect of CCBs on vascular smooth muscle is seen at

L-type voltage gated Ca2+ channels - impact at agonist-driven (NE) or receptor-operated contraction mechanisms is considered minimal - relaxation effects on arterial smooth muscle, minimal efffect on venous smooth m. --> NO impact on preload, decreased Afterload * Normal dosing of DHPs leads to relaxation WITHOUT excess sympathetic response - is excessive SNS response, can co-treat with Beta blockers ** Non-DHPs will also cause arterial relaxation, BUT their actions on the nodal tissues will blunt the SNS reflex response

Superior Mesenteric A. branches from the abdominal aorta at the level of

L1

The transpyloric plan is at the level of

L1

Inferior Mesenteric A. branches from the abdominal aorta at the level of

L3

Mitral valve (AKA Bicuspid Valve)

LA to LV

Cholesterol transport is done via

LDL and HDL mainly - LDL delivers cholesterol to peripheral tissues - HDL scavenges it from the periphery for delivery to the liver

Composition of LDL vs HDL ("the yin and yang of cholesterol transport")

LDL: - mostly cholesterol esters (often said to have more free cholesterol ** LDL carries 70% of plasma cholesterol (LDL-C) ** High LDL-C is a MAJOR risk factor for cardiovascular disease, especially coronary artery disease HDL: - mostly cholesterol esters - higher percentage protein (bc they are smaller than LDL) - higher percentage of phospholipids (in order to proved fatty acyl chain source for esterifying free cholesterol to cholesterol esters)

The secretion of NaCl from crypt cells is

LOW at ALL locations from duodenum --> jejunum--> ileum --> proximal colon--> distal colon * we have a lot of NaCl secretion and H2O with it to make sure that no one place is really dried out

Colonic Digestion and Absorption of Nutrients is

LOW but NOT zero - bacteria inside the colon digest trace food particles and some cellulose from small intestine for their own growth, etc. ** remember that some bacteria DO have ability to process cellulose to some degree, so for them there will always be some food supply among what for humans is indigestible dietary fiber- bc of this the colon will never be sterile except under very rare conditions (Ex. Bowel prep followed by mega-doses of antibiotics prior to bowel resection) A side effect of bacterial digestion is the production of relatively water-soluble short chain fatty acids (SCFA) ** the epithelial cells can then absorb few bacteria-produced SCFA from colonic lumen as a final source of nutrients for the body (they have specific transport proteins for this purpose)- Unlike the LCFA made by SI, these do not have to be esterified into TAGs prior to exiting the colonocytes - which the colon can then absorb via secondary active transport - some vitamins are also produced by bacteria Fermentation by-products include acid and gas which in clinical conditions of malabsoprtion in the small intestine can lead to osmotic diarrhea, pain, and flatulence

The smooth part of the ventricles are made from the

LOWER HALF Bulbus cordis gives rise to smooth parts of - RV (conus arteriosus) - LV (aortic vestibule)

What is the role of LPL (lipoprotein lipase)?

LPL is an extracellular enzyme that is anchored by heparan sulfate to the capillary lumen walls of most tissue, especially those of adipose tissue, cardiac and skeletal muscles - its synthesis and transfer to luminal surface of the capillary in adipose tissue is stimulated by insulin - activated by apo C-II - isomers of lipoprotein lipase have different Kms for TAG - LPL is ABSENT in adult liver, which has hepatic lipase on the endothelial surface- hepatic lipase assissts mainly in HDL metabolism

Hypertensive patients are most likely to have cardiac pathology showing

LV hypertrophy

Aortic Valve

LV to aorta

Describe the Lacunar, Pectineal, and Reflected inguinal Ligaments

Lacunar Ligament: - deeper fibers of external oblique aponeurosis pass posteriorly to attach LATERAL to the pubic tubercle to form an arch Pectineal Ligament: - most lateral lacunar ligament fibers continue to run along pecten pubis (MEDIAL to femoral canal) Reflected Inguinal Ligament - superior fibers of external oblique aponeurosis and lacunar ligament fan upwards crossing the linea alba instead of inserting into the pubic tubercle

Possible Diagnoses involving Vomiting

Large-volume hematemesis (grossly bloody or black, like coffee grounds) - major upper GI bleeding from peptic ulcer, esophageal varices, or Mallory-Weiss tear Vomiting with a history of head trauma: - concussion - skull fracture - trauma related epidural or subdural hematoma Vomiting with headache: - intracranial bleed, mass, or infection, meningitis, migraine

Elastic Arteries (conducting arteries)

Largest type of artery (>1cm in diameter) Exs: Aorta Brachiophealic Common Carotid Subclavian Arteries --- Tunica Initma: consists of endothelium (simple squamous), basal lamina and an underlying subendothelial layer containing SMCs Tunica Media: consists of SMCs and many organized elastic fibers which for sheets known as LAMINAE (lamellae/membranes) ** characteristic feature of elastic arteries=Laminae Tunica Adventitia: consists of elastic fibers, which provides further elasticity, and collagen fibers, which limit the stretch of elastic arteries ** Tunica adventitia is THINNER than tunica media in elastic arteries

Inferior Mesenteric Artery which supplies the Hindgut has 3 branches which are:

Left Colic Artery * forms part of the marginal artery of Drummond Sigmoid Arteries Superior Rectal Artery ---------- NOTE: Parasymp. Innervation to this area is Pelvic Splanchnic Nerves Symp. Innervation to this area via Lumbar Splanchnic Nerves (L1-L2) for Pre-ganglionics and via Inferior Mesenteric Ganglion for Post-ganglionic cell bodies

The spleen is ovoid in shape and is typically a "pulpy" mass located in the

Left Upper Quadrant (LUQ) - lies on the mid-axillary line and is an intraperitoneal organ - it is the LARGEST lymphatic organ in the body (capable of marked expansion and relatively rapid contraction) - it acts as a blood reservoir (identifies, removes and destroys old RBCs) & recycles iron and globin *** it is NOT a vital organ (can remove it and still live) although it is HIGHLY vulnerable due to its close relationship with the ribs *** the Spleen is NOT a GI organ because it does not have to do with digestion but it is located in the abd region

On the posterior surface of the liver what veins can be seen

Left hepatic vein, Middle Hepatic Vein, and Right Hepatic Vein which drain into the Inferior Vena Cava which drains into the R. Atrium

Tay-Sachs disease

More common type of lipid storage disorder, autosomal recessive - caused by lack or inactivity of the lysosomal enzyme hexosaminidase A (HEXA) which breaks down gangliosides (GM2 type) under normal conditions (note: gangliosides are made and degraded rapidly in early life as the brain develops) * deficiency or inactivity of HEXA leads to accumulation of GM2 gangliosides in nerve cells of brain, spinal cord, to some extent spleen, leading to malfunction of these organs due to degeneration at tissue level ---- - classically characterized by infantile onset (healthy at birth, sxs by 3-6months of age) pts die by age 3- its initially notice by excessive startle response sxs: growth retardation, difficulty swallowing, seizures, decreased mental skills and muscle tone (strength), deafness, blindness, paralysis * fundoscopy shows a grey-white area around the retinal fovea centralis, due to lipid-laden ganglion cells, leaving a central "cherry-red" spot - this happens well into the disease usually after a diagnosis is made on other sxs * rare form can develop in late childhood or early adulthood

Presentation of Transposition of great vessels

Most affected infants present with cyanosis most often within first 2-3 says, and may req. resuscitation Sxs - blueness of the skin - SOB Incompatiblie with life unless an accompanying shunt such as VSD, patent foramen ovale, or patent ductus arteriosus exsists: indeed those with a large ventricular septal defect or patent ductus arteriosus may NOT be diagnosed until severeal weeks of age Treatment: - baby will immediately receive a prostaglandin through an IV: helps keep the ductus arteriosus open, allowing some mixing of the two blood circulations *****HIGHLY CYANOTIC

Describe the mechanism of carbohydrate absorption

Most carb absorption takes place in the duodenum and early jejunum- but there are transport proteins for carb absorption all the way into the ileum *** glucose and galactose both compete for the same apical transporter, SGLT-1 (SGLT-1 uses sodium to make a concentration gradient to bring things into the cell- ex. glucose and galactose)- this is secondary active transport because it requires ATP from the Na+/K+ ATPase on the basolateral ECF - Note that there is a GLUT-5 on the apical membrane which allows facilitated diffusion of fructose into the cell - On apical side there is a GLUT-2 which can bring out glucose, galactose or fructose to the basolateral ECF - there is also K+ transporter that brings K+ out to the basolateral ECF

Transposition of the Great Vessels

Most common cause of severe CYANOSIS in newborn - 20-30/ 100000 live births - more common in males than females (3:1) - Maternal facotrs associated with an increased rick include rubella or other viral illness during pregnancy - Spiral septum not formed instead the septum runs "striaght down" - thuse aorta arises from RV and pulmonary trunk from L - Right to L shunting of blood after birth *** Blood goes to lungs, pucks up oxygen, and then goes right back to lungs without ever going to systemic circulation - blood from systemic circulation returns to the heart and goes back to the systemic circualtion without ever picking up oxygen in the lungs

During the basal state, (prior to eating)

"empty stomach" - acid content is high ("old" gastric juice" - gastric juics secretion rate is low, with a higher pH (mostly chief cell product) THEN, if ingestion occurs - inducible flow increases (mostly from parietal cells) - very acidic gastric juice --- so on - Empty stomach the H+ ion conc. of gastric juice (mEq/L) starts high then drops when food is ingested, then rises again - Volume of stomach starts empty (just above 0mL) and as the mealis eaten peaks at 800mL then empties over next few hours - Rate of H+ ion secretion in mEq/hr rises later than these two because the secretion of this "new" gastric juice is a direct response to the high pH and high nutrient content of the stomach- it peaks and then falls as secretion of high-acid juice becomes less and less important ** knowing this the process by which food buffers old stomach acid and then the new stomach acid is secreted

Gastrointestinal Stromal Tumors (GISTs)

"stromal" because not certain which cell it is developed from - GISTS are the MOST COMMON mesenchymal neoplasms of the GI - arise in the smooth m. pacemaker interstitial cell of Cajal, or similar cells - they are defined as tumors whose behavior is driven by mutations in the KIT gene (85%), PDGFRA gene (a growth factor receptor (10%), or BRAF kinase (rare) - 95% of GISTs stain positively for KIT (CD117) - Most (66% occur in the stomach) - MOST gastric GISTs have lower malignant potential than tumors arising elsewhere in the GIT (some can be malignant- especially more distal in GI)

What are the 2 internal ducts of the pancreas?

(Main) Pancreatic Duct: (AKA duct of Wirsung) - Unites with the common bile duct - Opens into the GI tract with the common bile duct via the MAJOR duodenal papilla in the 2nd part of the duodenum - Runs from the tail of the pancreas, through the parenchyma of the gland to the pancreatic head Accessory Pancreatic Duct: (AKA duct of Santorini) - IF present & patent (so ONLY if formed in development) - Opens into the GI tract via the MINOR duodenal papilla in the duodenum - Usually communicates with the main pancreatic duct

Elements of a Run Chart

* Can be used for improvement The center line on the run chart is the median Can be used to: - Use 2 simple tests to determine if special cause variation is present - To see change over time ** Run charts are most useful for knowing when change occured and if a improvement is sustainable

Describe the Mucosal Immunity of the Genitourinary tract

* It is highly variable unlike the GI tract It has: - unique situation due to hormonal influences - great variability in structure and function at diff. locations and at different times - its physical barrier defenses provided mainly by epithelium and mucus secretion as well as flushin action of urine - its epithelial cells express receptors for pathogens (PRRs) and do respond to antigenic challenge like similar cells at other location ** it is very few inductive sites (some lymphoid aggregates however)- still it has a big response to infection even without inductive sites

Describe the pressure changes associatesd with Classic Primary Peristalsis initated by the swallowing center

* NOTE: the esophageal phase has BOTH Primary and Secondary Peristalsis Resting pressures (baseline) - near zero (atmospheric pressure), away from sphincters - above zero (contracted) at BOTH sphincters- sphincters are closed * sphincter needs to relax to zero for it to open * UES briefly drops to near zero to open and receive food- then briefly rises above its baseline to drive foor further into esophagus ***** Peristaltic wave (PRIMARY peristalsis) begins below UES - vagal signals causes LES to open until food is passes- then like UES pressure briefly rises above baseline, food enters stomach ------- Overview: - persitalsis produces a wave of contraction forcing swallowed material to move caudally though the esophagus and then enter the stomach - sphincters relax at the appropriate times to let this material through and then they close again - for the UES, the would be skeletal m. directly controlled by swallowing center - for LES, the would be smooth m. directly controlled by the ENS but under heavy extrinsic (vagal) tone ** if some residual material remains behind after primary peristalsis, then a sensing- and motor peristaltic reflex similar to those found elsewhere along the gut wall will initiate a secondary peristalsis- this wave of contraction will clear the residue out of the esophagus

Vomiting involves both GI and respiratory effort- can you list the steps involved in Vomiting

* Vomiting reflex: Reverse peristalsis, usually with an open upper esophageal sphincter (UES): 1. Activate medullary vomiting center by one or more stimuli 2. Pyloric sphincter and stomach relax to receive intestinal contents (sometimes)- in this case antiperistalsis of intestinal wall properls materials into gastric lumen 3. Increase in intraabd. pressure (assist in retrograde peristalsis), mostly by contraction of skeletal muscle surrounding the abd. cavity 4. Relaxation of stomach, LES, and esophagus reduces resistance to flow 5. Contraction of abd. skeletal muscles creates pressure to force gastric contents into the esophagus *** when stomach, LES, and esophagus all relac there will be a little resistance to a pressure wave generated by abd. skeletal muscles 6. A. If UES CLOSED- retching occurs- closure of UES is only voluntary activity (uses skeletal m.) possible during this process and it can be overcome by strong CNS vomiting center commands (ex. trying to find better place to vomit) B. If UES OPEN- voluntarily otherwise: Vomitus forced into oral cavity, through open mouth (this is why vomiitng can be dangerous if lying down- turning over to vomit is a life saving reflex (thorax highg and head low and facing down) C: Respiratory center coordinates involuntary ventilation to prevent aspiration of vomitus (make sure youre not breathing in when vomiting) ( a short sharp inspiration followed by the next ejection of vomitus and simultaneous forced expiration)

Describe the histological layers of the gut tube

* composed of the FOUR layers that are common to the whole gut tube from the esophagus to anal canal 1. Mucosa: simple columnar epithelium, lamina propria and muscularis mucosae 2. Submucosa 3. Muscularis (inner circ. and outer longitudinal) ** remember that the stomach had an extra oblique layer 4. Serosa/adventitia ***2-4 are derived from splanchnic mesoderm ***epithelial lining however is derived from the endoderm (from endodermal primitive gut tube) *** neural crest cells provide neuronal component

Formation of the vitelline duct

* initially the midgut is completely open to the cavity of the yolk sac - as folding proceeds, the connection is constricted to form the vitelline (omphalomesenteric) duct - the vitelline duct is ultimately incorporated into the umbilical cord and then degenerates as development proceeds

Describe the control of the Lower Esophageal Sphincter

* it is all physiological (ENS) it as no anatomic sphincter like in UES which was skeletal M.- which had motor units that where either turned on/off by brain stem For LES Between swallows: Parasympathetic Vagal Excitatory Fibers (VEF): - use ACh as NT (SP secondary) - stimulate circular muscle contraction - sphincter stays closed DURING swallow: Parasympathetic Vagal INHIBITORY Fibers (VIF): - Use VIP as main NT (NO secondary) - INHIBITS circular muscle contraction - sphincter opens to receive food ** there are both excitatory and inhibitory parasympathetic neurons ** it all depends on which NT each drop on the same target tissue- the control center in the brainstem determines which PNS motor neurons will fire at any given time to provide a given tone to the LES smooth muscle ** at the LES, this typically overrides intrinsic reflexes

SMCs (smooth muscle cells) of Elastic Arteries

** If somethine goes wrong with the SMCs in elastic aa. they are vulnerable to injury- if injured they are difficult to repair - SMCs in TUNICA MEDIA lie between elastic laminae and are joined by GAP JUNCTIONS allowing cells to contract together in response to stimuli SMCs: - produce extracellular components of the tunica media (elastin, collagen, reticular fibers and proteoglycans) - proliferate and repair the TUNICA INTIMA in response to growth factors secreted by endothelial cells

Vascular resistance of vessels arranged in parallel

** The total resistance of a parallel system is LESS THAN the lowest individual vessel resistance (this explains why capillary system provides such a low resistance, despite the fact that each capillary has a relatively high resistance) ** Therefore a parallel arrangement of vessels greatly reduces resistance to blood flow- this is why capillaries which have the highest resistance of individual vessels bc of their small diameter, consistute only a small portion of the total vascular resistance of an organ or microvascular network 1/Rtotal= 1/R1 + 1/R2....... This arrangement also means that - the resistance of arterioles in one organ can be changed without significantly altering the total resistance of the vasculature- permititng redistribution of blood flow in instances such as exercise without causing a massive drop in BP ** when there are many parallel vessels, changing the resistance of a small number of these vessels will have little effect on the total resistance for the segment

Describe the histology of the large intestine (colon, rectum, anus)

*NO villi/ plicae circulares! but YES crypts* 1. Mucosa - simple columnar (just like SI), no villi nor plicae circulares, but crypts are still present a. Epithelium: columnar absorptive cells, goblet cells (most numerous), EEC and stem cells (so cells similar to SI) b. Lamina propria: cellular, prominent lymphocytes and scattered nodules (same as SI) c. Muscularis mucosae: smooth m. like SI 2. Submucosa - NO brunners glands nor peyers patches like SI 3. Muscularis externa - inner circular and outer longitudinal layer - outer longitudinal layer is formed into 3 longitudinal strips (not complete, instead forms 3 bands)= taenia coli 4. Serosa/Adventitia

Origin of the Anterior Intercostal Arteries

- 1st-6th from Internal Thoracic (Mammary) artery - 7th-9th are from the Musculophrenic artery ** Musculophrenic & Superior Epigastric aa. are terminal branches of the Internal Thoracic Artery which was a branch of the Subclavian aa.

Gastroenteritis (AKA Infectious Diarrhea)

- 70% due to viruses- Effects are mainly due to fluid and electorlyte loss (bc mainly affects large bowel whose main role is to absorb fluid and electrolytes) - Small intestinal effects can also occur as in cases of Giardia Intestinalis (but this does not produce significant histology bc it is more dealt with our microbiota)

Peptic Ulcer Disease Complications

- A change in the character of the patients typical pain may herald a complication - Abrupt onset of severe or generalized pain may indicate perforation with spilling of gastric or duodenal contents into the abd cavity, resulting in peritonitis ** a chest x-ray can demonstrate free air under the diaphragm from perforation of a peptic ulcer - Rapid onset of mid-thoracic back pain may be due to posterior penetration into the pancrea, with development of pancreatitis - Nausea and vomiting may indicate gastric outlet obstruction from scarring or edema - Vomiting of bright red blood or coffee-ground material and/or passage of dark tarry stool (melena) or hematochezia may indicate bleeding from a peptic ulcer

During the cephalic and gastric phases of pancreatic secretion

- ACh stimulates both acini and ducts to secrete - this prepares the duodenum to receive nutrient-rich acidic chyme and neutralize the acid when it arrives - this prevents any damage to duodenal wall when chyme first arrives

Chronic Pancreatitis can be due to:

- ALCOHOLISM - Genetic: PRSS1 & SPINK 1 (Hereditary Pancreatitis), CFTR mutations (cystic fibrosis) - AUTOIMMUNE - TROPICAL PANCREATITIS: Africa & Asia (poorly defined, some cases have hereditary basis)

Effects of sympathetic stimulation

- APs are generated more freq. and propagated through the heart more rapidly - venricular APs are shorter in duration at higher heart rates - strength of contraction associated with each AP is greater - rate of development of ventricular pressure increases - rate of ventricular relaxation is greater (positive lusitropic effect) so the duration of each contraction (systole) is reduced

Signs of Acute Pancreatitis on Physical Exam

- Abd may be distended with reduced or absent bowel sounds - Guarding and rebound may be absent as pancreas is retroperitoneal - Rare physical exam findings may include evidence of hemorrhagic pancreatitis such as flank (Grey-Turner sign) or periumbilical (Cullen sign) ecchymosis - Signs of systemic inflammation are common at the time of presentation including fever, tachycardia, and leukocytosis

Common Clinical Presentations of GI pathologies

- Abd pain (may be acute or chronic, we will focuse on acute abd pain) - Vomiting - Retching - Diarrhea - Constipation - Indigestion - Bloating

Conditions associated with dysfunction of the lower esophageal sphincter:

- Achalasia (also a form of dysphagia) - Achalasia= "failure to relax" - Gastroesophageal reflux disease (GERD) - Barrett Esophagus

Antacids work to decrease gastric acidity. These include

- Aluminum hydroxide/Magnesium Hydroxide - Calcium carbonate - Sodium bicarbonate MOA: Inorganic compounds that react with gastric hydrochloric acid (HCl) to form a salt and water - reduces intragastric acidity Chemical Breakdown of each: Al(OH)3 + 3HCl --><-- AlCl3 + 3H2O Mg(OH)3 + 2HCl --><-- MgCl2 + 2H2O CaCO3 + 2HCl --><-- CaCl2 + CO2 + H2O NaHCO3 + HCl --><-- NaCl + CO2 + H2O *** Sinc Calcium carbonate and Sodium bicarbonate realease CO2, a side effect of these can be increased distension, bloating and belching

Below the costal margin and above the arcuate line (upper three quadrante of rectus abdominis) one can find the

- Anterior Lamina (sheet): a combination of the TOTAL aponeurosis of the external oblique and the ANTERIOR half of the aponeurosis of the internal oblique and the - Posterior Lamina (sheet): a combination of the POSTERIOR half of the aponeuroses of the internal oblique and the TOTAL aponeurosis of the transversus abdominis muscles ** the 3 aponeuroses join in the midline at the linea alba

Common cardinal veins in embryonic period and their derivatives

- Anterior cardinal --> SVC (from R anterior only), internal jugular veins - Posterior cardinal --> Common, external, internal iliac veins, root of azygos vein - Subcardinal --> portion of IVC, suprarenal veins, gonal veins - Supracardinal --> portion of IVC, intercostal veins, hemiazygos vein and rest of azygos vein

Boundaries of the Abdomen

- Anterior: bounded above thoracic cage and below the abd muscles and fascia - Posterior: bounded by lumbar vertebrae, crura of diaphraghm, psoas and quadratus lumborum muscles and post. part of iliac bones - Laterally: again bound by thoracic cage and below by abd muscles and fascia - Superiorly: bounded by diaphragm - Inferiorly: continues with pelvis

What are possible changes that can alter the Microbiota:

- Antibiotics change ratio of microbiota (single 10 day treatment takes 3-6 months to re-establish proper balance) - Changes in diet (selects for organisms that best use those foods- takes up to 6 months to adjust) - Prebiotics/probiotics increase the abundance of some species - Disease states also alter ratio of species (Diabetes, Stress and anxiety, and Depression) ------ Environmental changes in the gut result in a changed ratio of organisms, with a chance for overgrowth of a species Diet changes alter the biome and can lead to changes in gas and bloating as well as steatorrhea - Ppl on High carb diets have species that are predominantly fermenters of carbs - Ppl on high protein diets have fewer carb fermenters and a greater abundance of organisms that ferment fat and protein - Person on high fat diets without significant fiber develop a greater abundance in species that can ferment fats

Possible complication of MI include

- Arrhythmias (first 24 hrs) - Pulmonary edema - Cardiogenic shock - Cardiac arrest - LV wall rupture (3-7 days after_ - Hemopericardium & cardiac tomponade - RV wall ruptue

The liver RECEIVES blood from two different sources

- Arterial (oxygenated via celiac trunk) from the Hepatic Arteries (20-25%) - Venous (nutrient rich- but oxygen poor blood) from the Hepatic Portal Vein (75-80%) - this blood goes to the liver first to detoxify!

Abnormal Lipoprotein Metabolism is directly or indirectly implicated or related to many clinical problemds such as

- Artherosclerosis - Hypertension - Coronary artery disease - Lipoproteinemias (hypo- and hyper-) - Fatty Liver Disease * Abnormal lipoprotein metabolism is implicated in or correlated in many cardiovascular diseases- these are a major cause of mortality

Celiac Disease:

- Autoimmune disorder that can occur in genetically predisposed people where the ingestions of GLUTEN leads to damage in the small intestine (a gluten intolerance) - the body mounts an immune response that attacks the small intestine - these attacks lead to damage on the villi * estimated to affect 1 in 100 ppl worldwide * results in coble-stone appearance b/c the villi are destroyed *NOTE: once gluten is eliminated from the diet- the stem cells allow the villi to grow

Absorption of VitB12, Cobalamin in the intestine and transport in the blood requires specific factors such as

- B12 is initially bound to transcobalamin I (AKA Haptocorrin, R-factor): secreted by salivary glands, to protect it against stomach acid - B12 then binds tightly to intrinsic factor, a protein secreted by parietal cells of the stomach - B12/intrinsic factor complex is absorbed in the ileum - In the blood, B12 is transported in complex with transcobalamin II, another protein, to be carried to the liver through the portal circulation * re-absorption in the intestines preserves B12 - B12 lost to excretion in the bile is recovered through re-absorption in the intestine **** A main source of Vit B12, cobalamin deficiency is loss of intrinsic fator bc loss of parietal cells (autoimmune or aging of the stomach)

Thoracic Wall Reference Planes

- Based on palpable (superficial) anatomical landmarks - Facilitate anatomical & clinical description of structures and procedures Examples: - Jugular (suprasternal) notch - Sternal angle - Anterior median line - Midclavicular line - Axillary fossa - Anterior axillary line - Midaxillary line - Posterior axillary line - Spinous process of C7 - Scapular lines - Posterior median line

Vitamin A has several functionalities such as

- Beta-carotene and retinol are absorbed in the intestinal mucosa. Beta carotene is cleaved to retinal. There, they are esterified with FAs and transported via chylomicrons to liver - Retinol is further transported in the circulation bound to retinol binding protein - Retinoic acid, formed from retinol, binds to nucler receptors and regulates gene transcription - Beta-carotene is also an anti-oxidant ---------- Free retinol from the liver is transported bound to retinol binding proteins VitA and related compounds serve multiple purposes: - Miaintenance of vision- forms visual pigments. 11-Cis retinal is bound to opsin and absorbs light. The absorption causes photoisomerization to all-trans retinal - Important also in reproduction, promotion of growth, and in differentiation and maintenance of epithelia

Describe the epithelial cell secretions in the respiratory tract that aid in chemical immunological defense

- Beta-defensins: promote bacterial lysis via pore formation, are chemotactic for many leukocytes and promote phagocytosis - Cathelicidins: posses broad spectrum antimicrobial activity against many organisms including Gram + and - by disruption of membrane integrity - Surfactant Proteins A & D: are collectins that are produced by type II alveolar cells- they promote phagocytosis (opsonins) and are directly bactericidal by destroying bacterial membranes - Lysozyme (Muramidase) is found in most secretions and is able to cleave the cell wall of Gram + bacteria

Overview of Bile production and Path

- Bile produced by hepatocytes flows through the bile canaliculi, bile ductules, and bile ducts - Bile leaves the liver in the L and R hepatic ducts, which merge with the common hepatic duct which connect to the cystic duct serving the gallbladder - the later two ducts merge to form a common bile duct **** ALL these ducts carrying bile are lined by cuboidal (more superiorly) or low columnar cells (as get into emptying into 2nd part of the dudoenum) called cholangiocytes, similar to those of the small bile ductules in the liver - The main pancreatic duct merges with the common bile duct at the hepatopancreatic ampulla (which enters the wall of the duodenum at a major papilla (of Vater) - The accessory pancreatic duct enters the duodenum at the minor papilla ** bile and pancreatic juices are mixed before release into the duodenal lumen

Treat of Irritable Bowel Syndrome (IBS)

- Biopsychosocial approach: psychological support and fostering the physician patient relationship is part of optimum managment - Dietary changes (increase dietary fiber- moderate quality evidence) Medications: - Tricyclic antidepressants (high quality evidence) - Antispasmodic, ex. dicyclomine, pepperment oil - Antidiarrheal, ex. loperamid, do NOT help with pain - 5-HT4 agonists (prokinetic in action, ex. Tegaserod for constipation type) - 5-HT3 antagonists (ex. alosetron for diarrhea type only)

The gut tube is open to the external environment via the

- Bucco (oro) pharyngeal membrane which breaks down in the 4th week, and forms the mouth opening (stomodeum) - Cloacal membrane which ruptures in 7th week, creates opening for the anus and urethra

Presentation/Symptoms in a Case of Peptic Ulcer Disease (PUD)

- Burning epigastric pain, may also be described as sharp, dull, aching, or an "empty" or "hungry" feeling - May be relieved by ingestion of milk, food, or antacids, presumably due to buffering and/or dilution of acid - Recurs as the gastric contents empty, and the recurrent pain may classically awaken the patient at night - Pain tends to occur daily for weeks, resolve, and then reoccur in weeks to months Note: Postprandial pain, food intolerance, nausea, retrosternal pain, and belching are NOT related to peptic ulcer disease (so could be a conern for a cardiac patient)

By the end of week 3 (day 22/23) the heart tube is beating and is now too long to be accomodated in the volume available as a striaght tube, the result is that in week 4

- Caudal (atrial) portion shifts DORSOCRANIALLY and to the LEFT - Cranial (ventricular) portion moves VENTROCAUDALLY and to the RIGHT **** and the Atrium will now be located CRANIAL to the ventricle

Describe the anatomical organization of the pancreatic ductal tree

- Centroacinar cells are terminal end duct cells that interface with acini - Terminal ducts or intercalated ducts are composed of flat epithelial and merge into intralobular ducts that are lined by cuboidal epithelia - Intralobular ducts merge to form small interlobular ducts surrounded by mesenchyme - Larger interlobular ducts are lined by columnar epithelia - These then drain into the main pancreatic duct (duct of Wirsung) - The pancreatic duct empties into the duodenum *** NOTE: centroacinar cells and intercalated ducts both have receptors for secretin

Lipid digestion uses 3 enzymes whicha re

- Cholesterol esterase (makes cholesterol which is directly taken up) - Phospholipase (makes glycerylphosphorylcholine)- which can be taken up direct absorption or by FA transport/direct absorption in enterocyte - Pancreatic Lipase **** MOST IMPORTANT (this one makes 2-monoacylglycerol which can be taken up by FA transport/direct absorption into the enterocyte)

Gastrointestinal Autoimmune Diseases include

- Chrons Disease - Ulcerative Colitis - Celiac Disease (AKA gluten enteropathy) ---------------- Autoimmunity- failure of an organism in recognising its own constituent parts as non self, which allows an immune response against its own cells and tissues. Any disease that results from such an aberrant immune response is termed an autoimmune disease.It is often caused by a lack of germ development of a target body and as such the immune response acts against its OWN cells and tissues "loss of self-tolerance"- doesnt tolerate your own antigens in own cells

The extrahepatic portal triad is made up of the

- Common bile duct - Hepatic artery proper - Hepatic portal vein ** these divide in the liver where they are called the intrahepatic branches of the portal triad

Acute inflammation is characterized by

- Congestion (increase bloof flow at sight of infection) - Edema (escape of fluid into area- small blood vessels become more leaky) "Cellular Infiltrate": - Neutrophils (AKA polymorphs)- short lived - Eosinophils- parasites & allergies - Basophils- hypersensitivities - Lymphocytes- may be the main cells in chronic & viral inflammation - Macrophages- "clean up guys" attracted to all forms of inflammation especially in the later stages

Caudate lobe of the liver

- Contigusous with right lobe of liver - separated from the right lobe by the IVC - Possesses its OWN venous drainage, so this hypertrophies in patients with obstructed hepativ v. outflow ( most notably, Budd- Chiari syndrome)

Electrophysiological actions of Metoprolol (Class II agent)

- Decreased conduction (stronger in AV node) - Increased Refractoriness (markedly in AV node) - Decreased Automaticity

Development of the Midgut

- Duodenum: (distal) 2nd, 3rd, and 4th parts - Jejunum - Ileum - Cecum - Appendix - Ascending colon - Transverse colon: proximal 2/3rd -------------- Midgut rapidly expands during week 5 resulting in U-shaped mid-gut loop, with two limbs: - Cranial Limb: distal duodenum, jejunum and upper part of the ileum - Caudal Limb: rest of the ileum, and rest of the midgut

How can you differentiat the 3 regions of the small intestine easily?

- Duodenum: brunner's gland in submucosa (more pale) and possess a leaf-like shaped villi - Ileum: contains peyer's patches in submucosa (darker stain) and possess finger-like shaped villi) - Jejunum: NO brunner's glands, NOR Peyer's Patches but the vili and crypts visible

Histological Development of Gut Tube and its Effects on the Lumen

- Early second month epithelium proliferates and lumen obliterates - Recanalization and rearrangement of tissue to yield the correct type of epithelium (ex. Simple columnar) ** If this does NOT happen it can result in stenosis or atresia Normally: Hollow gut tube --> gut tube occluded by endodermal proliferation --> recanalization --> definitive hollow gut tube

Internal and External Elastic Laminae (same elastic lamellae)

- Elastic arteries contain elastic laminae of similar thickness - Large muscular arteries contain (internal elastic lamina between tunica intima and media and external elastic lamina between tunica media and tunic adventitia) - Small arteries contain internal elastic laminae NOT external elastic lamina ** Internal and external laminae are NOT present in veins

Partitioning of reactions allows for a more thorough digestion and higher yield of energy from the food eaten, therefore

- Enzymes are stored in secretory vesicles where their activities are inhibited prior to secretion - Some enzymes are produced in conjunction with inhibitors to further reduce organ self-digestion - pH changes in the organs allos for the inactivation of previously added enzymes and the activation of organ specific enzymes - High vascularization and high surface area of the small intestine result in the majority of water and nutrient absorption occuring therein

3 layers of the Heart Wall Include

- Epicadrium (AKA visceral layer of serous pericardium) - Myocardium - Endocaridum (associated with the lumen of the heart)

National Dietary Concerns

- Epidemic Obestiy - Rising levels of metabolic syndrom - Increased incidence of Diabetes (Note: Diabetis req. special diets to balance sugar) - Hypertension - Cardiovascular disease Causes: - overall preference for processed food> fresh fruits etc. - excess calorie consumption, increased portions - increased soda and juice and fast food consumption leading to excess consumptiion of refined sugars, salt and saturated fats - low fruit and veggie intake - inadequate fiber intake and calcium intake - sedentary lifestyle- decresed physical activity

Standard US diet

- Focused on US foods - Emphasized nutrient-dense foods and appropriate amounts Appropriate mix and proportions - veggies, fruits, grains, dairy, proteins (seafood, meats, poultry, eggs, nut seeds, soy), oils - Calorie limits for other uses ~270 (non-nutrient dense foods) ** some foods need adjustment according to their density- usually based on 2,000 calorie diet

Common Dietary concerns and deficiencies

- Folate/B12: inadequate veggies/meat consumption - Calcium: osteoperosis- can be concern when there is prolonged lack of calcium in diet, vitamin D deficiency (lack of sunlight, lack of VitD rich foods)- give calcium supplements or increase levels in diet. Good sources: fortified cerels, cheese, yogurt, almond milk, tofu, orange juic, milk - Iron: of concern for adolescent girls and women ages 19-50, also more iron is needed during pregnancy. Good sources: legumes, dark-green veggis, and fortifies foods (breads and cereals), VitC enhances consumption - Zinc: can be replensihsed by supplements or appropriate foods - Sodium (consumed in excess)- can affect hypertension- recommended to limit sodium in the diet (limit cheese, processed foods that contain added salt, dont use salt shaker at the dinner table). Recommended: <2,300mg/day sodium (2.3g/day) - Alcohol (excess) --- - Inadequate nutrition: poverty, increased req. (ex pregnancy), poorly balanced vegeterian diet - Malabsorption - Chronic Illness - Alcohol use and alcoholism

Thoracoabdominal nerves (T7-T11) consist of which axons

- General somatic efferent (GSE) axons: carry MOTOR info to initiate contraction of muscle fibers - General somatic afferent (GSA) axons: carry SENSORY information from the skin (lateral cutaneous nerves and anterior cutaneous nerves) * T7-T11: they run between the layers of abd muscles to innervate the muscles of the anterolateral abd wall - anterior and lateral and cutaneous branches provide nerve supply tothe skin

Peritoneal cavity can be divided into

- Greater Sac: main compartment - Lesser Sac: hidden from view ** the peritoneal cavity is a space between parietal and visceral peritoneum, it can be divided into two "sacs" that are formed during foregut rotation

What is formed from the dorsal mesentery (embryonic)

- Greater omentum (gastrorenal, gastrosplenic, gastrocolic, and splenorenal ligaments) - mesentery of small intestine - mesoappendix - transverse mesocolon - sigmoid mesocolon

What types of things lead to mucosal damage (ulceration)

- H+ - Pepsin - NSAIDS - Microbes - Toxins

Describe the Mechanism of Parietal Cell HCl Secretion:

- H+ and Bicarbonate made inside parietal cell from CO2 and water, and intrinsic factor made by protein synthesis - Cl- in via Cl-bicarbonate antiport, and goes out (apical) via CFTR - K+ comes in via Na-K pump and H-K pump, out via leak channels (leak channels give enough K+ for the H-K pump which gest its K+ from the Na+/K+ pump) - H+ out (apical) via H-K pump * Carbonic Anhydrase inside the cell makes HCO3- and H+ used in the above and below listed here - Bicarb out via Cl-Bicarb antiport - Intrinsic Factor out via exocytosis (IF keeps cobalamin from being digested) - Water follows ions out as in other secretory cells (tight junctions prevent backflow of acid) Final result: HCl and water in the pit lumen, bicarbonate in the venous blood leaving the stomach

Signs of a case of Acute Appendicitis

- HYPOactive bowel sounds - severe tenderness with rigidity and reboud in the R iliac fossa - Psoas test and Rovsing sign are usually POSITIVE ** Psoas test is positive in case of retrocecal appendicitis - Murphy and obturator signs are usually NEGATIVE ** Obturator sign MAY be positive in case of pelvic appendicitis **** therefore, psoas and obturatory signs will NEVER be positive in a same patient

What are several helpful tools and methods in diff domains of Interest that could help to implement change?

- Healthcare as process within systems: uses diagrams: flow, inter-relationships, cause-effect, narrative description, cases ex - Variation and measuremtn: use data recorded over time and analyzed on run charts and control charts - Customer/beneficiary knowledge: measuremnet of illnes of burden, functional status, quality of live, recipients assessment of their care (satisfaction) - Leading, following and making chaang: take initiave or adaptive action, reviwing and reflecting, developing both leadership and follower-ship skills - Collaboration: managing conflict, building teams and group learning, acquiring specific communication skills (ex. SBAR) - Social context and accountability: identifying an eliminating unwanted, unnecessary variation, widespread public sharing of info - Developing locally useful knowledge: making small tests of change (PDSA cycle)

Typical Thoracic Vertebrae

- Heat-shaped vertebral body, long spinous process - Typical vertebrae has 3 facets on each side for articulation with the ribs; two demifacets and transverse costal facet * NOTE: not all vertebrae articulate with ribes in the same fashion For a typical vertebrae: the rib articulates with the vertebrae above and below (Ex. 7th rib articulates with T6 and T7)

Describe the Structure and Organization of Hepatocytes

- Hepatocytes may have one or two nuclei - Contain an abundance of RER, SER, ribosomes, numerous mitochondria peroxisomes, lysosomes, multiple Golgi complexes, many lipid droplets and glycogen - Organized into one or two cell thick anastomosing plates that are separated by sinusoids (seperated rows of hepatocytes) - Hepatocytes are cube like, with 6 major surfaces. 4 of these surfaces typically abut on similar surfaces of adjacent hepatocytes (lateral domain). The other two hepatocyte surfaces face the sinusoids on either side of the plate and are covered by short microvilli projecting into the space of Disse (sinusoidal domain)

Effects of Inflammatory gastrointestinal disease are determined by:

- Host factors (adult? child?) - Severity/extent of disease (can vary) - Specific region involved (diff locations affect diff. functions) - MALABSORPTION (would see sxs of nutrients being deficient)

Vomiting and its association with acute and life-threatening conditions

- Hyperemesis gravidarum - Acute fatty liver of pregnancy (AFLP) - HELLP syndrome (hemolytic anemia, elevated liver enzymes, low platelet count) - Intra-abdominal emergency (obstruction, perforation, peritonitis) - Acute myocardial infarction - CNS disorder (infection, hemorrhage, intracranial mass) - Toxic ingestion - Upper GI bleeding

Cardiovascular pharmacology can be used in management of

- Hypertension - Ischemic Heart Disease - Arrhythmias - Heart failure - Vascular Disorders - Hemostasis - Infectious Disorders Ex. A pt with multiple BP readings of ~158/94, HTN, predisposing increased symp tone and Na+--> needs to be treated with drugs

Consequences of repeated (chronic) vomiting- leads to loss of low pH gastric juice (not intestinal juice) which can lead to

- Hypovolemia: leads to increased aldosterone (from renin-angiotensin system) and ADH which activate the kidney leading to low H2O excretion, and high K+ and H+ acid excretion (increased aldosterone exacerbates the hypokalemia, increased ADH worsens the hyponatremia- and non-respiratory alkalosis - loss of K+ (hypokalemia) - loss of Na+ (hyponatremia) - loss of H+ (non-resporatory alkalosis) * normally these disturbances will be corrected by combined actions of kidneys and lungs- but repeated vomiting can lead to the hypovolemia * parietal cells normally return one bicarbonate ion to the blood for every H+ secreted into the gastric lumen- the equivalent amount of bicarbonate ions are normally secreted by the pancreas and used to buffer the secreted H+ ions that enter the duodenum- when these H+ are lost in vomit- they are NOT buffered by HCO3- in duodenum and so plasma bicarbonate rises as does plasma pH - the high levels of aldosterone also promote renal acid excretion making the alkalosis worse

Describe the control of gastric emptying

- Increase pressure in the stomach and you increase the gradient for emptying - Increase resistance and you oppose emptying * at some point increased pressure + reduced resistance: results in materials flowing past the pylorus (AKA gastric emptying) * this can be viewed as neural control with both intrinsic and extrinsic components, and heavy hormonal/luminal content modulation *NOTE: that as w/ the LES, the vagus n. has BOTH inhibitory and excitatory neurons that influence pyloric tone: - neurons that release ACh: increase contractile force of the circular smooth m. - neurons that release VIP and/or NO: decrease smooth m. contractile force- thus lowering resistance to emptying * the combined tone from the 3 autonomic NTs (2 parasympathetic and 1 sympathetic) helps maintain the "just right" degree of constriction- helps to make sure that only particles of a very small size pass through and at a rate that the SI can handle in its digestive processing - in emptying of nondigestive contents (ex. swallowed coin) the pylorus is capable of great relaxation so that larger materials can be emptied into the SI for eventual disposal in feces (ENS reflexes also matter) * Several hormones and luminal contents modify this ANS/ENS control Ex: CCK and gastrin both increase pyloric tone and thereby resistance to gastric emptying - in an empty-of-nutrients stomach, motilin increases gastric motility and the pressure gradient for emptying - other minor GI hormones may also play a role

Peptic Disease

- Increased production of gastric acid (uncommon- only seen with some drugs & hormones) - Decreased protective factors Can occur in esophagus all the way to duodenum. Esophagus: - gastric acid on non resistant squamous mucosa due to reflux from stomach Ex: Esophagitis, Intestinal Metaplasia (occurs with chronic damage to esophagus can lead to --> Barretts Esophagus (the boundary where esophagus ends and stomach starts no longer easy to differentiate) Stomach: - reduced protective mechanisms due to H.Pylori infection, NSAIDs, Increased acid production (Gastrinoma, Drugs) - Chronic peptic ulcer in stomach can lead to: Necrosis of lining of mucosa, inglammation, granulation tissue, and scarring if chronic Duodenum: - reduced protective mechnisms (especially before Ampulla of Vater) - damage here can also lead to break down/ulcerations ---- NOTE: Ulcers can also occur with ischemic (lack of blood/oxygen) supply in severe trauma, burns, intracranial lesions/trauma

Chronic inflammation

- Infectious/irritant agent NOT CLEARED though SOME CONTAINMENT - tissue damage mainly due to inflammatory response (bc immune system trying to remove infectious agent) - reparative processes with FIBROSIS (SCARRING) - LYMPHOCYTES and HISTIOCYTES (macrophages which may fuse to form larger multinucleated (giant) cells ** histiocytes --> macrophages --> fuse to giant cells

Which trace minerals are required in the diet at less than 1mg/day

- Iodine - Selenium - Chromium - Molybdenum - Cobalt - (Fluoride): dont need this but it is important for other reasons

Which trace minerals are required in the diet at an RDA below ~100mgs

- Iron - Zinc - Copper - Manganese

Vitamin C (AKA Ascorbate)

- Is an antioxidant ( a reducing agent), it can also act as a free-radical scavenger, and prevent free-radical propagation and damage to tissues - it is req. as a coenzyme to hydroxylate proline and lysine residues in collagen (makes up CT) via prolyl hydroxylase (this is responsible for many of the symptoms of Scurvy) It is also req. in other hydrozylation rxs such as: - synthesis of NE from dopamine req. ascorbate-dependent hydroxylase - bile acid synthesis req. and ascorbate-dependent hydroxylase It is also req. for carnitine synthesis which req. two Fe2+ containing, ascorbate-dependant oxygenases - Ascorbate also facilitates iron uptake by reducing ferric to ferrous iron * ascorbate can be oxidized to Dehydroascorbate *** megadoses (gm) of VitC once found to be helpful against the cold and also may be useful when given as one part of an IV treatment for sepsis (this sepsis thing is still under investigation)

Describe the Anal canal

- Its histology is highly complex It has 2 embryological origins and this determines its histology: Upper 1/2- anal columns of anal canal: - simple columnar - hindgut origin - superior rectal artery (branches of the inferior mesenteric artery) ----------Pectinate Line-------- Lower 1/2 of anal canal: - stratified squamous non-keratinized - inferior rectal a. (branches of internal pudendal artery) --- Anus: stratified squamous keratinized of skin

How is the fetal circulation different from the circulation AFTER birth?

- L umbilical vein--> fibroses to form the round ligament of the liver - Ductus venosus --> Fibroses to form the ligamentum venosum - Umbilical arteries: the proximal part remains in the adult as the umbilical artery, the distal part (that runs towards the umbilicus) becomes a fibrotic cord called the medial umbilical ligament

Run Charts vs Control (shewhart) charts

- Like run charts, control charts plot a single line of data over time - control charts include upper and lower control limit lines with a centerline, providing more statistical control ** magic number for identifying both shifts and trends on a control chart is 7 (although often used >/= 6 & >/= 5 respectively on run charts)

Cardiac Ion Channels

- Many different classes and sub-type of ion channels - The electrical properties of a tissue depend on which ion channels are expressed in the membrane In CARDIAC MUSCLE, the main channels involved in membrane excitation are for Na+, K+ and Ca2+ ions & there are some channels that are NOT SELECTIVE for one particular ion *** In this case the Nernst of REVERSAL POTENTIAL of the current will reflect the relative permeability of ALL permeant ions Ex. A channel mixed but EQUAL permeability for BOTH Na+ and K+ has a reversal potential between the Nernst potential of these ions (Na+, +60mV; K+, -90mV) i.e. -90 x 0.5 + +60 x0.5= -45++30mV= -15mV (this is the Reverse potential) ** NOTE: 0.5 is used because there is EQUAL permeability to Na+ and K+ in this problem

What are some acid-base considerations associated with vomiting

- Metabolic Alkalosis: with gastric-only vomiting - Metabolic Acidosis: if green bile and pancreatic juices are vomited

Acute Pancreatitis can be:

- Metabolic: ALCOHOLISM, hyperlipoproteinemia, hypercalcemia, drugs (azathioprine) - Genetic: mutations in the cationic trypsinogen (PRSS 1) and trypsin inhibitory (SPINK 1) genes - Mechanical: GALL STONES, tumor, trauma, iatrogenic (medical intervention/procedures) - Vascular: shock, arthero-embolism, polyarteritis nodosa - Infectious: mumps, coxsackie virus

Vomiting and Specific Illness Scripts (*remember these are not the end all be all- there can be exceptions)

- Migrations of periumbilical pain to RLQ is characteristic of acute appendicitis - Abd pain before vomiting is common in abd pathology - Female patient with RUQ abd pain and bilious vomiting, steady pain lasting > 30 minutes (biliary colic) is characteristic of acute cholecystitis - Acute chest pain with pain radiation to arm(s) with vomiting- consider acute myocardial infarction or gastro-esophageal reflux disease - Postural symptoms, lethargy, unable to retain oral liquids for >8hrs in a child (>12hrs in an adul)- consider likelihood of hypovolemia and/or electrolyte imbalances requiring urgent treatment - Vomiting with paresthesias, blurred vision, dysphagia, muscle weakness- food-borne toxins (botulinum, paralytic shellfish toxin)

What are some abnormalities of development in liver or gallbladder?

- Minor variation in liver lobulation common, NOT clinically significant - Duplication of gallbladder (can get 2 gallbladers with 2 cystic ducts etc.)- this is usually asymptomatic

Vegetarian Diet

- Modified from US healthy pattern - based on eating patterns of vegetarians - meets nutrient guidlines low in proteins (3.5oz) ** note- for strict vegans, dairy can be replaced with appropriate vegetables - calorie limit for other uses ~290 (non-nutrient dense foods) ** highest in grains ** lowest in proteins

Basic Concepts of Motility

- Motility is driven by muscle contraction in the gut wall - General direction is either from Oral --> Anal/Caudal (peristalsis) or Back and forth (mixing/segmentation) * Direct control: in most of GI tract incolved an Enteric Nervous System (ENS) which has sensory and motor compoentns * Indirect control: can often be exerted by ANS mechanisms and by hormones (including the gut-produced entergastrones)

Organs of digestion play specific roles as the food passes through such as:

- Mouth --> size reduction and hydration, minor digestion - Stomach --> protein denaturation and digestion - Small intestine --> digestion of all biomolecules and absorption - Large intestine --> recycle bile salts, modification of vitamins, absorption

Familial Hyper-cholesterolemia

- Mutations in the LDL receptor - NO LDL uptake in peripheral tissues ** Defects in LDL uptake leads to excess LDL in circulation- In combination with oxidation of LDL, these are taken up by macrophages and form foam cells- foam cells participate directly in artherosclerotic plaque formation ** Discovery of role of LDL in cardiovascular disease is what led to creations of HMG-CoA reductase inhibitors (Statins) Homozygotes: - develop SEVERE artherosclerosis at a very early age (<20) Heterozygotes (1:500) develop high plasma cholesterol and are substantially more susceptible to coronary artery disease

The Enteric Nervous System contains two nerve plexuses with cell bodies that coordinate reflexes along the gut wall- these are the

- Myenteric (AKA Auerbach's) plexus: controls GI motility by controlling the smooth muscle layers of the muscularis externa - Submucosal (AKA Meissner's plexus): controls GI secretions (controls mucosal and submucosal glands, and the mucosal fold-producing muscularis mucosae) ** "M's never match!" ------- ENS sensors are found BOTH at the mucosal layer (chemical sensors, etc.) and in the gut wall (stretch receptors) - motor fibers from ENS are both stimulatory and inhibitory - the control of which motor neurons are activated in turn controls of the mitility and secretion of the guy

Gallstone and Acute Cholecystitis

- Obstruction of the biliary lumen may cause inflammation of the biliary tree - Obstruction of the flow of bile from the liver to the duodenum may lead to obstructive jaundice - An impacted stone in the common bile duct (CBD) can cause jaundice - Cystic duct stones do not typically cause jaundice - Very rarely a very large stone in the cystic duct pressing on and obstructing the CBD can cause jaundice

Describe the Serosa and Adventitia of the esophagus

- Only the portion that is in the peritoneal cavity is covered with serosa (bc this is part where you can let organs move around a little more) ; the rest is covered by adventitia (it is all adventitia at the deepest layer- helps to hold everything in place and connect esophagus to rest of abd cavity

What is the role of oxidized LDL in arterial plaque formation?

- Oxidized LDL can lead to Endothelial cell injury - Monocytes adhere to the subendothelium and are transformed into macrophages - Macrophages engulf excess oxidizedLDL and become foam cells - Foam cells accumulate and release growth factors and cytokines that induce smooth muscle cell migration

Submandibular Gland

- Paired gland - Found within the submandibular triangle (AKA Digastric triangle) which corresponds to the region of the neck immediately beneath the body of the mandible - Comprised of a superficial and deep portion * this is one of the MAJOR salivary glands - the Submandibular Duct (of Wharton) runs from anterior end of deep portion and opens into the sublingual caruncle at the side of the frenulum of the tongue

Parotid Gland

- Paired glands - Located anteriorinferior to the ear - EACH has a parotid duct (AKA Stensen's Duct) that conducts saliva secreted from the gland to the oral cavity - the parotid duct pierces the buccinator muscle and enters the oral cavity opposite the 2nd maxillary molar tooth ** this is one of the MAJOR salivary glands

Steatorrhea

- Pale, malodorous stool - whenever lipids cannot be properly digested- the undigested material will appear in a pale, foul-smelling stool - often associated with diarrhea from waste products of bacterial fat metabolism, thus the "orrhea" associate with the fat "steat" * whether this loss of digestions is secondary to lack of bile secretion or loss of pancreatic enzyme secretion of both, the effect on the patient is inadequate digestion and absorption of lipids, which is then pass into stools - it can also be due to low motility resulting in too many bacteria in the small intestine

Overall recommendations for dietary carbohydrates

- Percent of diet: 45-65% of calories: at least 130g/day (~520 calorie minimum) - limit added sugars (<10% of daily calories)- one coke can/ day - eat grains (6oz eq/d for 2000 Cal diet): 1/2 whole grains - include dietary fiber (~25-35g/d): by including the whole grains to 50% of total grains, include beans or other sources in diet

Vit K, Quinone has 3 known forms which are

- Phylloquinone (plants), K1 - Menaquinone, K2 - Menadione, synthetic K3 Action: Acts as a co-substrate for gamma-glutamyl carboxylase (adds a second carboxylate group to the glutamates- making them capable of binding calcium which is req. for their mech. of action) - this carboxylation matures clotting factors II, VII, IX, and X (2,7,9,10) - Vitamin K is then regenerated using another enzyme (Vitamin K epoxide reductase) so that it can be re-used as a substrate for the gamma-glutamyl carboxylase --- WARFARIN (Coumadin), an anticoagulant, acts as a competitive inhibitor to vitamin K epoxide reductase- inhibiting the regeneration of VitK *** K stands for "Koagulation" since it affects clotting factors ***

Pleura Cavity

- Pleural cavities are lined by pleural membranes - Viseceral pleura: covers and attaches DIRECTLY to the lungs (**NOT a part of the thoracic wall) ** Pleural Cavity= the potential space between the 2 pleura which contains Pleural Fluid*** - Parietal pleura: (found right under the Endothoracic Fascia) Lines the thoracic wall including the diaphragm

R/L Vitelline Veins give rise to what structures

- Portion of the IVC (R vitelline) - Hepativ veins and sinusoids - Ductus venosus - Portal vein - Inferior mesenteric vein - Superior mesenteric vein - Splenic vein

What are some different locations for the Appendix- where appendicitis can occur

- Preileal - Postileal - Promonteric - Pelvic - Subcaecal - Paracolic/precaecal - Retrocaecal

Starting after an overnight fast, right before a meal (when the stomach has absolutely nothin in it except a small amount of high-acidity gastric juice (State 1). Then ingestion begins and we see what is going on about 1.1hrs after breakfast (State 2). State 3: 2.25hrs after breakfast. State 4: as the stomach is almost empty- 4.5hrs after meal was eaten. Describe the processes of which food buffers the old stomach acid and then the new stomach acid is secreted, all of which play a key role in getting the stomach to empty

- Prior to ingestion of food- in the empty stomach parietal cell secretion is very low. The hydrogen ion concentration of gastric juice is very high (reflecting a very low pH)- and the food level is zero. Under these circumstances there is no reason to secrete acid - Ingested food buffers "old" gastric juice, so pH inside stomach rapidly rises (see 1hr mark)- acid secretion will be needed to re-acidify the stomach - These and other changes associated with a meal are sensed and parietal cells are activated. With activation, the HCl component of newly secreted gastric juice becomes much greater and over time the pH of the stomach becomes more and more acidic- this helps activate pepsin to increase chemical digestion of proteins - As stomach becomes increasingly empty of food products, all of the nutrient-based signals (ex. elevated AA levels) that had been stimulating hydrogen secretion decline while those stimulating somatostatin secretion increase, such that by several hrs after the meal, the stomach is empty, hydrogen secretion has declined to baseline, and the pH of the stomach is back to its usual very-low pH (aka high hydrogen ion concentration)

High Density Lipoprotein, HDL

- Produced by intestine and liver - Carries out reverse cholesterol transport - Reservoir of apo C-II and apo E Nascent HDL: - Disk-shaped - Contains apo A-I, C-II, and E - Contains primarily phospholipid (PC) - Collects cholesterol to become HDL3 HDL3: - Collects cholesterol and further matures into HDL2 HDL2 (mature HDL): - Depleted in lipids, rich in cholesterol esters - CE for TAG exchange with VLDL - Goes to liver to drop off CE and TAG --> HDL3 - HDL3 returns to circulation

Manifestations of MI can be due to LV pump failure characterized be

- Pulmonary edema: congestion in pulmonary circulation - Cardiogenic shock: loss of effective blood flow with widespread end-organ hypoperfusion - Cardiac arrest: irrerversible loss of effective cerebral blood flow with loss of consciousness - req. resuscitaton, otherwise progresses to biologic death

Venous Drainage of the stomach

- R and L gastric veins drain to the hepatic portal vein - R. gastro-omental veins drain into the superior mesenteric vein - L. gastro-omental veins and short gastric veins drain into the Splenic Vein - Prepyloric Vein --> drain to R gastric vein ** Ultimately they all drain to the Hepatic Portal Vein --> Portal Venous System (liver --> IVC--> R atrium of heart)

What are the 3 gastric secretions in "NEW" gastric juic

Mucus - protective against gastric acid - secreted by mucous neck cells in gastric pit and gastric epithelium elsewhere - contains bicarbonate and glycoproteins to protect epithelium from damage by contents of luminal gastric juice - relatively low volume in gastric pit-derived gastric juicse Chief cell secretion product - high in NaCl, NOT bicarbonate or acid - Pepsinogen (immature form) secreted via exocytosis - hgiher proportion secreted at basal (lowest) flow rates Parietal cell secretion product - high in HCl - intrinsic factor secreted via exocytosis - MUCH higher proportion secreted at maximal flow rates *** highest yield cell secretion in gastric juic= HCl acid from parietal cells ------ In secretion of gastric juice, all 3 cell types listed here contribute to volume and composition of new gastric juice that exits the gastric pits to mix with the pre-existing gastric juice in the lumen (aka "old gastric juice') - that said, mucus will be low in volume compared to either of others bc its components dont go far from cell surfaces * it is the composition of the combined gastric juice, not the newly creted juice alone which determines the pH of the gastric lumen before and after a meal is consumed - the replacement "new" juice will help to correct a pH that is too high or too low

Wherever a bolus of food or other sensible material is, sensors send the location information to the

Myenteric Plexus --> activates smooth muscle as follows: Oral (orad, side closer to the mouth) - circular muscle contracts and longitudinal muscle relaxes - this increases pressure oral to the bolus - this increases resistance to flow "upstream" - creates the narrow "propulsive segment" Caudal (anal, side close to anus) - circular muscle relaxes and longitudinal muscle contracts - reduces pressure caudal to the bolus - reduces resistance to flow "downstream" - creates the wide "receiving segment" - the bolus then moves from the high-pressure "propulsive segment" to the low-pressure "receiving segment" * sensors at downstream site detect the bolus and the process begins again ** this is NOT a continuous process rather it proceeds in steps- this link shows peristalsis occurring every few seconds in a section of small intestine

Ischemic heart disease (IHD) aka Coronary artery disease (CAD) or Coronary heart disease (CHD)

Myocardial oxygen demand exceeds myocardial oxygen supply--> cell injury and death (necrosis, infarction) Most common cause: coronary AA (Arthersclerotic) plaque with reduced blood flow and superimposed thrombosis Risk factors: same as atherosclerosis *** there is sequential progression of coronary artery lesion morphology beginning with stable chronic plaque responsible for typical angina and leading to various acute coronary syndromes

Vitamin B3, Niacin is converted to

NAD (a dinucleotide) and NADP, both of which serve as redox carriers and co-enzymes for numerous reactions - NAD (P) can also be made from a tryptophan metabolite, quinolinate (about 60mg of tryptophan are needed to make 1 mg of niacin- which allows you to make half of what you need but this is very inefficient) * Niacin is part of NAD+ and NADP+ * NAD+: electron carrier * NADP+: is for synthetic reactions for reducing equivalents

Is acute inflammation an acute infection?

NO! Acute inflammation occurs in acute infection and other acute inflammatory processes (but one is not the other)

Is the sphingolipid, glycolipid a phospholipid?

NO! sphinomyelin is a sphingolipid that is a phospholipid

Unlike in many other cells, VIP is ________ in pancreatic acinar cells

NOT INHIBITORY! VIP works to activate pancreatic acinar cells

Viscocity is a property of the bolue that is

NOT directly affected by either circular or longitudinal smooth muscle - for purposes of short-term motility, viscocity is a property that the enteric nervous system control of gut muscle CANNOT directly affect

A large amount of water reabsorption is secondary to absorption of ions, particularly

Na+ and Cl- - unlike in secretion where for most purposes Cl- secretion led to Na+ following the Cl- ABSORPTION is more common for sodium to be absorbed/reabsorbed and then the Cl- and water follow the sodium in * there are exceptions such as the cotransporter with hydrogen and dipeptides/tripeptides, but generally water follows sodium -------- It is possible to bring in BOTH sodium and chloride across the apical membrane, so long as there is carbonic anhydrase available on the luminal side of the apical membrane to turn H+ and HCO3- back into H2O and CO2 - on rare occasions, like severe dehydration- the colon becomes involved in aldosterone-associated absorption of sodium and water to complement that occuring in the kidney- there is a special Electrogenic Na Channel (ENaC) associated with this all

Class I antiarrhythmic drugs block

Na+ channels

List the mucosal immune factors found in the: Nasopharynx, Lungs, Stomach, SI, Colon, Vagina, Bladder, Urethra

Nasopharynx: - resident microflora - secretions (lysozyme, phagocytes) - ciliated cells Lungs: - macrophages Stomach: - low pH - proteolytic enzymes Small Intestine: - fast flow - mucus - sloughing cells - bile salts Colon: - slow flow - mucus, sloughing cells - abundant resident microflora - bile salts Vagina: - low pH - resident microflora Bladder: - flushing action or urine - low pH - physical barrier of urethra Urethra - urine flow ----- Also NOTE: Eye: blinking, tears, lysozyme Skin: structural barrier, sweat sebum, lactic and propionic acid, lysozyme, normal flora Respiratory tract: coughing sneezing, mucus, ciliary action, phagocyte, lysozyme GI stract: stomach acidity, normal flora, peristalsis, antimicrobial compounds Urogenital tract: lavaging action of urine, acidity of urine, lysozyme, vaginal lactic acid (normal flora)

Nausea vs Vomiting vs Retching

Nausea: an unpleasant sensation vaguely referred to the epigastrium and abdomen, with a tendency to vomit- may be a symptom of a variety of disorders, some minor and some more serious Vomiting: indicates that stomach contents are expelled Retching: is the involuntary mechanical effort to expel stomach contents but nothing is expelled ("dry heaves")

Nervi Vasorum "Nerves of the Vessels"

Nerves which innervate arteries and veins (AKA vascular nerves or autonomic nerves) * Predominantly found in Tunica Adventitia - but occasionally in lower portion of Tunica Media These REGULATE the contraction of SMCs in the tunica media to control: - vasodilation - vasoconstriction

Starling Forces

Net Driving Pressure= Forces Out (Pc+ piI)- Forces In (Pi+ pic) - if equation yields a positive number- net fluid movement is occuring from capillary to the interstial space - filtration - if equation yields a neg number: net fluid moevement is occuring from interstitial space into the capillary- reabsorption

The lymphatic system

Network of thin walled vessels that collect excess interstitial fluid (lymph) from tissue spaces and return this fluid to the blod Role in immune system: - major distributor of lymphocytes, antibodies and other immune components which are carried through organs to and from lymph nodes and other lymphoid tissue Main components - lymph - lymphatic capillaries - lymphatic vessels - lymph nodes

The only IV DHP

Nicardipine - be ware of the SNS "Spike" ------ Nifedipine and Amlodipine are ORAL: sustained release formualtions available ---- NON-DHPS (Diltiazem and Verapamil) are available IV and oral

Nitric oxide (NO) role in myogenic theroy of blood flow regulation

Nitric Oxide (NO) is a lipophilic gas formed by endothelial cells which duffes to smooth muscle cellls and causes local vasodilation Endothelail NO production is stimulated by a variety of factors, some are: - paracrine agents (histamine via H1 receptors and bradykinin) - increased shear stress on the inner vessel wall (sheer stress leads to an increase in Ca2+ in endothelial cells--> NO syntahce which catalyzes synthesis of NO from arginine--> NO diffuses to adjacent smooth muscle cells and causes local vasodialtion) - ACh from cholinergic nerves

What are two types of motor acitivty in the proximal colon?

Nonpropulsive Segmentations (Haustrations in Proximal Colon) - churns increasingly solid contents - segments (haustra) very visible in radiograph *** the distal colon has mostly nonpropulsive segmentations which do not form fully-closed haustra: contents in descending colon lumen are just solid enough to prevent full closure of segments; in sigmoid colon even more so *** the rectum is kept nearly empty by nonpropulsive movements until a mass peristalsis fills it again or Mass Peristalsis (Mass Movement) - very powerful peristaltic contraction - one ring of contracted circular muscle moves in oral-to-anal direction - occurs 1-3 times per day - may move material 20cm or more at a time - may be initiated by eating (gastrocolic reflex- can help to move really hard to move material) - haustra disappear during this movement NOTE: the large intestine sometimes has different terminology than the small intestine for the same thing

Coronary Collateral Circulation

Normal Circulation: Anatomosese between the termination of coronary artery at: - Anastomoses at the apex: LAD (anterior interventricular artery) & Posterior interventricular artery - Anatomoses at the Coronary sulcus: Left coronary Artery circumflex branch & the Righ coronary artery terminal portion ** this is important in blockage of any of these arteries: at a sit of blockage there will be low pressure inferior to the blockage (so combo of low pressure & no valves- allows blood backflow through these anastomoses)

Normal esophagus vs. Acute Esophagitis

Normal= stratified squamous epithelium Acute esophagitis= inflammed cells migrating to mucosa- associated with fluid/edema, cells and blood vessels are dilated

Normally how many nutrients make it to the colon?

Normally only a trace quantitiy of nutrients make it into the proximal colon, which support a certain number of colonic bacteria but with certain digestive disorders (ex. pancreatitis)- absorption will NOT be complete by the time materials reach these living beings who naturally take advantage with major growth and waste production - the combo of unabsorbed foodstuffs and bacterial metabolic waste products can produce soft stools or even diarrhea, and infringe on body water balance from the intake side

What is the normal function of zymogens

Normally zymogens can auto-activate under special conditons - inhibitors provide a back up safety to autocatalysis Trypsinogen is a very poor at auto catalysis but 5% does auto-activate - occurs in the presence of bile salts and weak acidic conditions (pH 5.4-7.8) - trypsin activates all other pancreatic zymogens - if in presence of biles acids for long time trypsinogen begins to auto-activate and digest the pancrease ----------- Disease states: In gallstones: - any blockage of the bile duct causes the trypsinogen autolysis and can cause pancreatitis Alpha1-antitrypsin (inhibitor) deficiency - increases risk of pancreatitis and pancreatic cancer (this can be due to genetic mutation or environmental modification of met-358) Cystic Fibrosis - where there is a blockage of pancreatic secretions due to decreased secretion of water in the mucus

Septum formation in the ventricles

Not as complex as in the atria. Occurs completely BEFORE birth The interventricular septum (IVS) that partitions the ventricles is formed by 2 adjoining septa: 1. Muscular septum: derived from myocardium; form from expansion of heart muscle - End of the fourth week ventricles start to expand due to growth of the myocardium; medial walls become apposed and merge, ridge of tissue= muscular interventricular septum - 7th week muscular septum haults; does NOT fuse with endocardial cushion - Space between muscular IVS and cushions= interventricular formane 2. Membranous septum forms from: - Extension of tissue from endocardial cushion to the muscular portion of IV septum and - TIssue from the aortico-pulmonary septum (see partitiong of the outflow tract) *** NOTE: without migrating of neural crest cells there would be an issue here *** The IV septum is thus formed when the membraneous and muscular components fuse NOTE: as partitioning of the ventricles is taking place so is partitioning of the outflow tract

Arterosclerosis

Number 1 killer in the US today - Disease of the arteries characterized by a build up of fatty plaques in the TUNICA INTIMA of medium and large arteries - results in the restriction or obstruction of blood flow through the artery and can lead to heart attack - can lead to ischemic heart disease, myocardial infaction and stroke

Ventricular Septal Defects (VSD)

Occurs in 1 in 1000 individuals- it can be detected pre-natally Many small VSDs are ASYMPTOMATIC and clos spontaneoulsy- most frequently during the first year postnatally - More freq in males than in females - arise in any part of the IVS Membranouse VSD - most prevalent (70%) often associated with defects in aorticopulmonary septum therefore neural crest cells do not migrate Muscular VSD - less common than membranous - caused by single or, multiple small defects (swiss chesses VSD) Common Ventricle (cor triloculare biatriatum)= 3 chambers with 2 atriums (i.e. bi atrium and thus one ventricle) - failure of BOTH membranouse and muscular IV septum to form

The Enterohepatic Circulation states that

Of the total amount of bile acid entering the SI: 95% of secreted bile acids and salts are returned to the liver each pass Mechanisms of reabsorption at the terminal ileum inlcude: - Na+-dependent carrier-mediated (secondary active transport) for priamry bile SALTS only - Passive diffusion (free bile ACIDS)- primary and secondary only In the liver, - Secondary bile acids are mostly losst in the feces. Some are reabsorbed - Production of new bile acids tied to concentration of returning bile salts/acids - Both newly made and recycled bile acids are conjugated into bile salts before secretion ** Since bile takes several passages/day, ~20% of the bile acid pool is replaced daily through synthesis of new bile acids using pre-cholesterol precursors - The avg total bile flow is ~600mL/day

Small, fatty projections that are only found on the colon

Omental Appendices (AKA epiploic appendages/appendices epiploicae)

Manganese deficiency can cause

Osteoperosis - Manganese is important for healthy bones and cartilage, metabolism and reproductive functions - It is required for several enzymes: ATPases, Arginase, Pyruvate carboxylase, Peptidases, ICDH, GlucosylTransferases (TOXIC in excess) Found in: - grains, nuts, leafy veggies and soy products ~1.8-2.3mg/person

Epicardium of the Heart (AKA Visceral Layer of Serous Pericardium)

Outermost layer Consists of 2 Layers: 1. Simple Squamous Mesothelium: - lines the pericardial cavity - these cells secrete pericardial fluid into the cavity to prevent friction during heart beat 2. Mesothelium is supported by Loose CT which contains: - coronary vessels - autonomic nerves - adipocytes (fat) that cushion the heart * epithelium that lines the pleurae, peritoneum, and pericardium

Tunica Adventitia (Externa)

Outermost layer of blood vessel Composed of: Connective tissue - Mainly type I collagen Fibers (provides structural strength) - Some elastic fibers (provides elasticity)

Blood flow in the liver is from the Periphery --> the center

Oxygenated blood comes in from the hepatic artery and nutrient-rich, DE-oxygenated blood comes in from the Hepatic portal vein ---> both travel to the liver sinusoids --> Central Vein --> Hepatic Vein --> Inferior Vena Cava --> Right atrium of the heart --- BILE FLOW IS OPPOSITE from the CENTER --> Periphery (bile produced in the hepatocyte flows out to the bile duct in the portal triad)

In acute appendicits, when appendicitis progresses, the inflammation then irritates the

PARIETAL peritoneum - General somatic afferent (GSA) axons supplying the muscles and skin localize the pain at McBurneys Point McBurneys Point: - indicates the base of the appendix - 1/3rd of the way from ASIS (anterior superior iliac spine) to the umbilicus - in the Right lower quadrant (RLQ)

In terms of gastric acid secretion, Vagal Neurons (parasympathetic)

PNS vagal neurons (preganglionic) act on the ENS submucosal plexus - the postganglionic neurons shown are ENS motor neuorns going out to the various secretory and regulatory cells in this location- so parietal cell secretion while directly controlled by the submucosal plexus of the stomachs ENS is subject to HEAVY modulation via the vagus nerve Stimulate: - parietal cells (direct effect) - ECL cells to secrete histamine (indirect) - antrum G cells to secrete gastrin (indirect, uses GRP (a NT called gastrin releasing peptide) Inhibit: - D cell secretion of somatostatin (indirect)- this is inhibiting an inhibitor so it KEEPS SECRETION GOING!

The Splenic Vein is formed by many tributaries that leave the hilum of the spleen. The Splenic Veins runs _____ to the body of the pancreas

POSTERIOR! NOTE: - the inferior mesenteric vein usually drains into the Splenic Vein - the splenic vein unites with the superior mesenteric vein to form the Hepatic Portal Vein

ECG effects from Metoprolol (Class II agent)

PR interval: Increased QRS duration: unaffected QT interval: unaffected

ECG effects due to Class IV agents (CCBs)

PR interval: increased QRS duration: unaffected QT interval: unaffected

How does the GI induce tolerance in mucosal immunity (immunological signaling)

PRRs and PAMPs like TLR or NLR are present on the mucosal epithelium - the TLR and ligand can bind to generate a signal - signal transduction (protein kinase, etc.) - the signal travels to transcription factor NFKB or STAT and this sends signal to - the nucleus which upregulates genes for cytokine production and release cell recruitment, activation and effector function ** if there is no action at the nucleus it can be because one of the following is occuring: 1. No PAMPs? no activation 2. Receptor down-regulation? - One example of how TLR can be down-regulated is via TOLLIP (Toll interacting protein)- down-regulates TLR and stops the cell from reacting to antigen 3. Kinases down-regulation? 4. NFKB down-regulation? --- another ex. of something like this: if a B cell CANT make antibody in the nucleus it may mean there is something wrong with this similar pathway

Describe the synthesis of phosphatidylserine

PS is synthesized from phosphatidyl ethanolamine (PE) exchange via (phosphatidyl ethanolamine- serine transferase (base exchange reaction))- swaps serine for the phosphatidylethanolamine * exchange can be reversed: PS --> PE * PE can be used as a substrate for CHOLINE synthesis: - when liver PC is low and dietary choline is not available, the liver will synthesize PC- this is done by first decarboxylating PS to PE (useing phosphatidyl-serine decarboxylase) and then PE is methylated - PE conversion to PC is done with the action of N-methytransferase, S-adenosyl methionine is a substrate and the methyl group donor (this reaction is done 3 times to add 3 methyls) ** choline is usually sufficient in the diet, but this pathway can synthesize it- the synthetic pathway is insufficient to supply the dull daily requirements- so choline is req. in the diet - nonetheless, it is not considered a vitamin because it can be synthesized

SA and AV node are

Pacemaker cells (MODIFIED myocytes) - produce SLOW response action potentials ** these cells with intrinsic electrical (pacemaker) activity allows the heart to beat without any NS innervation

Phospholipase A2 and Cholesterol Esterase both are secreted by the

Pancreas (acinar cells) and act in the lumen of the entire small intestine

Cholangiocyte (ductular) HCO3- secretion into ductules and ducts is the same process as in

Pancreatic ducts Regardless of whether hepatic bile is being produced by hepatocytes for immediate delivery to duodenum or gallbladder bile is being squeezed out of gallbladder for delivery to the duodenum, all of the bile must pass through the bile ducts on the way. As in pancreatic ducts, this provides an opportunity for final modification of secreted product, particularly for increasing the concentration of bicarbonate and water in the bile. This process has two immediate consequences: - 1. It dilutes out some of the concentrated bile through increased CFTR activity ensures enough ductal lumen Cl- (CFTR activity is regulated), with sodium and water following the chloride - 2. It makes bile alkaline with antiport (HCO3, Cl-) puts bicarb. into duct ** the combination significantly reduces the risk of precipitation of calcium along the duct lining, helping to prevent blockages ---- - Na+ follows Cl-, HCO3- into bile duct lumen - water follows ions both through cells using aquaporins and between cells (paracellular) - H+ is a waste product, secreted bt the basolateral membrane **** Increased secretion of bicarbonate and water by secretin (raises cAMP levels just like the pancreatic ducts), glucagon and VIP (these both also increase cAMP levels) **** Decreased by somatostatin (via inhibitory G protein to reduce the amount of cAMP, inhibiting the secretin/glucagon/VIP stimulation of bile duct secretions)

Which lipase needs colipase, HCO3-, and bile salts to function?

Pancreatic lipase - which is secreted by the pancreas (acinar cells) - and alls throughout the lumen of the entire small intestine - needs colipase, HCO3- and bile salts to function bc buffered in HCO3-, colipase flips phosphlipid so that its sticking out of micelle so pancreatic lipase can digest it, micelles are created by subsequent bile salts

Peritoneal Recesses include

Paracolic gutters (R/L): - groover or space between the abd wall and the lateral aspect of the ascending and descending colon - allows communication between the supracolic and infracolic regions of the greater sac - important for peritoneal fluid flow Subphrenic recesses: - located below the diaphragm - separated into L and R by falciform lifament - potential site for fluid collection Subhepatic space: - immediately inferior to the liver Hepatorenal recess: - extension of the subhepatic space between the visceral surface of the liver and the R kidney - potential site for fluid collection

Even though Somatostatin is listed as a hormone, it only has ___ actions

Paracrine - whereever somatostatin is being secreted, some activity is being inhibited Ex: In stomach- Somatostatin inhibits gastric acid secretion

Blood supply within each circulation has a ______ arrangment

Parallel! Enables independently regulated blood flow to each organ or region Ex. In systemic circulation an arterial branch serves each major organ of the body from the aorta (parallel organization)- it is analogous to a city water system where each house is linked to a common water supply -- enables blood flow to each organ to be regulated independently of any other organ system

Innervation of the stomach

Parasymp--> Vagus (CNX) Sympathetic--> Greater Splanchnic nerves (T5-T9) NOTE: Celiac plexus of nerves wrap around the arteries to reach the diff. parts of the organ

Describe Innervation to the Gallbladder

Parasympathetic (GVE)--> Vagus (CNX) - parasymp. stimulation produces contraction of the galbladder, and the secretion of bile into the cystic duct due to relaxation of the sphincter of Oddi. The majority of this response however, is mediated by circulation cholecystokinin (CCK)) Sympathetic (GVE) --> Celiac Nerve Plexus NOTE: the gallbladder also receives general somatic afferent (GSA) innervation as the Right Phrenic Nerve carries this sensory information that can lead to referred pain ** irritation of the diaphragm: phrenic n. carries GSA axons (referred pain from the liver, gallbladder or duodenum to the upper shoulder) ** C3, C4, C5 keeps the diaphragm alive

Innervation to the Pancreas

Parasympathetic --> Vagus (CNX) Sympathetic --> Greater Splanchnic (T5-T9) via the celiac plexus and superior mesenteric plexus

Innervation of the Duodenum

Parasympathetic--> Vagus (CNX) Sympathetic--> Greater Splanchnic (T5-T9) and Lesser Splanchnic Nerves (T10-T11)

The following are protease that are inactive (zymogens) and change names when they are activated: Pepsiongen, Proenteropeptidase (Proenterokinase), Aminopeptidase N, Trypsinogen, Chymotrypsinogen, Proelastase, Procarboxypeptidase A, and Procarboxypeptidase B. What are their activated names? What activates them? and Where do they act?

Pepsinogen --> Activated by low pH and autocatalysis to form Pepsin (acts in lumen of stomach) Proenteropeptidase (proenterokinase)--> activated by trypsin to form enteropeptidase (works in lumen of duodenum- is membrane bound) Aminopeptidase N is made fully active and acts in duodenum and jejunum Trypsinogen --> activated by enteropeptidase to form trypsin (acts in lumen of duodenum) Chymotrypsinogen--> activated by trypsin to form alpha-chymotrypsin (works in lumen of duodenum) Proelastase --> activated by trypsin to form elastase (works in lumen of duodenum and jejunum) Procarboxypeptidase A --> activated by trypsin to form carboxypeptidase A (works in lumen of the duodenum) Procarboxypeptidase B --> activated by trypsin to form carboxypeptidase B (works in the lumen of the duodenum) ** most of these work in the duodenum EXCEPT pepsin - they wil work until they are digested and the furthest they can get before digested is usually the jejunum

Abdominal Exam: 3. Percussion

Percuss over the 9 regions -Vibrations initiated by tapping on the surface produce sounds that help characterize what lies beneath - We can measure the liver span and the clinical presence or absence of ascites - Normall percussion note obtained over a hollow air containing structure such as stomach and intestines are high-pitched, hollow quality, called tympanic - Percussion note over solid organs, masses, and fluid cavities are dull

Fibrous membrane covering the heart and the origin of the great vessels

Pericardium Has 3 layers: 1. Fibrous Pericardium - attached to the central tendon of the diaphragm and sternum Serous Pericardium (2 parts): 2. Parietal Layer of serous pericardium 3. Visceral Layer of serous pericardium (AKA epicardium) ** NOTE: the phrenic nerve provides somatic innervation to the fibrous and parietal layers

Baroreceptor Pathway (nucelus tractus solitarus)

Peripheral baroreceptor and chemoreceptor inputs enter the brainstem and synapse within the area known as the nucleus tractus solitarus (NTS) -an important "relay station" and "integration center" for afferent information froma variety of organ systems, including cardiovascular, renal and respiratory systems --------------- If BP increases: - baroreceptor discharge increases (these signals are conveyed from the carotid sinus and aortic arch by the glossopharyngeal nerve and vagus nerve afferents, respectively) - they terminate in nucleus of the tractus solitarius (NTS) and are excitatory using GLUTAMATE as their NTs - excitatory projections (glutamate) extend from the NTS to the caudal ventrolateral nucleus where they stimulate GABAergic INHIBITORY neurons that that project to the vasomotor center - Neurons in vasomotor area produce a tonic EFFERENT output (via bulbospinal pathway- glutamate) that increases heart rate, cardiac contractility, and vasoconstriction UNLESS inhibited by inputs into the NTS THEREFORE if baroreceptor discharge increases due to an increase in BP- the activity of GABA-ergic neurons increases-> reducing the tonic activity in the vasomotor center and its output via the bulbospinal pathway - this will decrease the EFFERENT tonic discharge via symp neuraons innervating the heart which will decrease HR, cardiac contractility, and induce vasodilation to decrease BP to counteract the elevated BP

Example of propulsion in the intestine

Peristalsis - Boluses are propelled in a caudal direction by weak peristaltic waves - Typical speed is about 1cm/min through the 7m of small intestine (it takes ~3-5 hrs for materials to pass from the pylorus to the ileocecal sphincter)

Potential space within the abd cavity is referred to as the

Peritoneal Cavity - it is "potential" space between parietal and visceral peritoneum * technically NO STRUCTURES are contained in the peritoneal cavity as the "space" is full of peritoneal fluid to enable peristalsis

NO structures lie between the parietal and visceral layers of peritoneum as this "space" is the

Peritoneal cavity - in life, fluid occupies this potential space to allow movement and mobilitiy of certain organs

The entire abdominal pelvic cavity is ALL lined with

Peritoneum - defined as a serous membrane (that secretes fluid to reduce friction when organs move) which: - lines the cavity and walls of the abdomen: parietal layer of peritoneum or - covers the abdominal organs: visceral layer of peritoneum

Lack of intrinsic factor (failure of secretion of acid and protective protein) can lead to

Pernicious Anemia ( a disorder of the stomach)

Double SVC

Persistence of the Left anterior cardinal vein resulting in FAILURE of the L brachiocephalic vein to form (as it develops from an anastomoses between L and R anterior cardinal veins when the CAUDAL part of the L anterior cardinal vein degenerates and the RIGHT SVC forms normally --- Anterior cardinal vein from the SVC (from right anterior only, and internal jugular veins)-------- Result: The left SVC drains venous blood from the left hand side into the RA via the coronary sinus, and the coronary sinus dilates to accomodate and increased blood flow

Ileal (Mechel's) Diverticulum

Persistence of the vitelline duct, thereby forming an out pocketing of the ileum - may become inflamed and associated clinically with symptoms resembling appendicitis Rule of Twos: 1. in 2% of population 2. apprx. 2 inches in length 3. usually found within 2 feet of the ileocecal valve 4. often found in children under 2 yrs of age 5. affects males twice as often as females

Bismuth Subsalicylate (AKA Pepto)

Pharmacodynamic/MOA: - protective layer against acid - antimicorbial (used in H. pylori) Pharmacokinetics: - oral - 99% of Bismuth excreted in feces - Salicylate is absorbed and excreted in urine Clinical uses: - Dyspepsia: gas, upset stomach, indigestion, heartburn and nausea - H. pylori drug regimen: used as part of a multidrug combination to eradicate the bacteria - Diarrhea Adverse Effects - Black stool (harmless)

Pancrelipase

Pharmacodynamics - equivalent to endogenous enzymes (a mix of lipase, amylase and protease) - extract of hog pancreas enriched for lipase, amylase, and protease - 6 products on market with varied ratios of enzymes Pharmacokinetics - oral: administer with food - dose to stool buoyancy Clinical uses: Therapy for malabsorption: - supplementation, pancreatic insufficiency: treatment of exocrine pancreas insufficiency caused cystic fibrosis, chronic pancreatitis, pancreatic resection Therapy for pain of chronic pancreatitis: - common practice (limited literature)

Proton-Pump Inhibitors

Pharmacokinetics: - ALL available oral; two also available IV - PPIs are administered as inactive pro-drugs; oral formulation are given as acid resistant enteric-coated formulations - Administer 1hr before a meal so that peak serum concentration coincides with maximal activity of proton pumps - NOT ALL pumps inactivated with the first dose; 3-4 day of the drug may be needed before full acid-inhibition is acheived Adverse Effects: - Most common: nausea, dyspepsia, flatulense, myopathy, arthralgia, headache - More serious: bone fracture, pneumonia, CKD, Dementia, C dif infection - Increased risk of hyperplasia of ECL in long term (>2 yrs) PPI therapy Drug Interactions - Some Hepatically cleared drugs by CYP (Cyp450) - Drugs with pH dependent absorption

Antacids

Pharmacokinetics: - Administered ORALLY- suspension preferred form - Vary in extent of absorption - ALL generally elevate urinary pH Adverse Effects: - Aluminum Hydroxide: constipation - Magnesium Hydroxide: osmotic diarrhea - Calcium Carbonate: hypercalcemia, constipation, hypophosphatemia, milk-alkali syndrome - Sodium Bicarbonate: hypernatremia, edema, and exacerbation of congestive heart failure * Antacids that produce CO2 can lead to excess flatulence and belching Drug Interactions: -Altered absorption due to pH changed and/or due to cation binding

Which is the most common phospholipase used to degrade phospholipids

Phospholipase A2 - it is activated through hormone signaling mechanisms - this can release arachiodonic acid from PI or PC- the arachiodonic acid is subsequently converted to prostaglandins which act as further downstream signals on nearby cells (paracrine signaling) ---- Other phospholipases: Type A (A2 and A1): cleave FAs from the glycerol backbone Type C: cleaves the headgroup between the glycerol and the phosphate - can release IP3 from PIP2 and generated DAG as well- this is part of hormone second messenger signaling systems (there are ~13 subtypes of phospholipase C and they are tightly regulated) Type D: cleaves the headgroup after the phosphate

What is the most common intracellular anion in the body?

Phosphorous RDA 700mg - Common in many foods - Hypo-phosphatemia can occur with aluminum-based antacids or general malnourishment. Also by excess parathyroid hormone (PTH) - Low phosphate causes muscle weakness - Decreased PTH can cause HYPERphosphatemia and metastatic calcification

Constipation

Physicians often define constipation as infrequenct passage of stool; however, patients often define it as straining to defecate or sensation of incomplete evacuation - May involve infrequent defecation, difficulty passing stool, or incomplete evacuation of stool - Constipation is common in older adults and requires careful assessment to rule out mechanical causes - May present with other abd complaints, such as pain, bloating, and/or gas - A diagnosis of chronic constipation required the presence of symptoms for at least 12 weeks

At autopsy, a 72 yr old man is found to have fibrosis of his pulmonary septa combined with numerous alveolar macrophages filled with small granules of hemosiderin. Most likely to also see

Pleural effusions (associated with pulmonary edema)

Osmotic Laxatives include

Polyethyleneglycol, Lactulose and Magnesium Hydroxide MOA: Osmotically mediated water retention - produce a rapid movement of water into the distal small bowel and colon - prompt bowel evacuation; within 1-3hours Pharmacokinetics: - Polyethyleneglycol: oral, Lactulose: oral and rectal - Onset: low dose= 24-96 hours, high dose= 1-3 hours Clinical Uses: - Treatment of constipation (all osmotic laxatives) - Polyethyleneglycol= used for colon cleansing before radiological, surgical, and endoscopic procedures - Lactulose= used to treat hepaticencephalopathy Adverse Effects: - Dehydration, electrolyte imbalance (all osmotic laxatives) - Lactulose: severe cramping and flatus (because it is metabolized by colonic bacteria)

Abdominal Exam: 1. Inspection

Position the patient: supine at 180 degrees (no pillows, knees fully extended, hands at the side- to ensure that abdominal wall is relaxed) Expose the abdomen from xiphisternum to symphysis pubis and look for: - abd contour (the 6F's of abd distension: fetus, fletus, feces, fat, fluid, fatal tumor) - abd symmetry - visible peristalsis - bulging of the flanks - visible pulsation and venous prominense - incisions, scars, hemorrhage/ecchymosis and hernias (in males, remember to examine the scrota for possible inguinal hernias)

Base of the heart

Posterior aspect OPPOSITE of the apex - formed mainly by the LEFT ATRIUM and partly by the right atrium - corresponds to the T5-T8 vertebrae - receives pulmonary veins (R&L) on its left atrial part (R/L Sup and Inferior Pulmonary Veins); and the SVC and IVC on its right atrial part ** Overlays the esophagus and thoracic aorta

The visceral surface of the liver is the ______ surface

Posteroinferior surface of the liver that faces adjacent abd organs From this view one can see the - Caudate Lobe - Inferior Vena Cava (IVC) - Left lobe - Ligamentum Venosum (remnant of the ductus venosus) - Round ligament of the liver (AKA ligamentum teres hepatis)- the thick free inferior border of the falciform ligament - Quadrate lobe - Portal triad: Common Bile Duct, Hepatic artery proper, Hepatic portal vein - Gallbladder - Right coronary ligament (laterally becomes the triangular ligament) - Bare area (Diaphragmatic area NOT covered in visceral peritoneum)

Fenestrated Capillaries

Presence of fenestrate (L, windows) in endothelial layer - Fenestrate can be bridged with diaphragms (which are "bridges" formed by extracellular matrix material that has a filtering function - fenestrated endothelium sits on a complete basal lamina - also feature pinocytic vesicles - more permeable than continuous capillaires ** Found in tissues where rapid exchange of substances between blood and tissues takes place (ex: kidney, the intestine, and endocrine glands such as the pancreas)

Congestive cardiac failure- heart failure cells

Presence of hemosiderin - pulmonary capillaries ruptured under pressure - RBCs entering alveoli are phagocytosed by alveolar MPs Excess iron in macrophage - bind to ferritin--> degrades into hemosiderine (rust colored granules H&E or blue with Prussion blue) ruse colored sputum

Valves of Veins

Present in large and medium veis - Consist of paired folds of TUNICA INTIMA that project in towards the lumen of the vessels - Reinforced with collagen and elastic fibers - Lined by endothelium Fx: - prevent back flow of blood

Afterload (resistanc that ventricle must overcome to empty its contents) may be increased by

Pressure overload - Ex. HTN, aortic stenosis, mitral stenosis, pulmonary HTN Reduced contractility -Ex. In Myocardial ischmia, inflammation (myocarditis)

A technique used to minimize blood loss during hepatic surgery by clamping the blood vessels entering the liver (entering through the porta hepatis or hilum of the liver)

Pringle Maneuver (described by Dr. Pringle) - the Portal triad (Hepatic artery proper, Hepatic portal vein, Common bile duct) travels within the hepatoduodenal ligament and this can be clamped to control bleeding *** If a patient is STILL bleeding internally after clamping, there must be a hemorrhage elsewhere which could be for exampled from the (Retrohepatic) inferior vena cava (remember R, L, Midd hepatic vein drain into the IVC)

Describe the digestion & absorption of most water-soluble nutrients

Processing --> Luminal digestion with secreted (luminal) enzymes --> Brush border digestions (with brush border enzymes) --> Absorption (with brush border transporters) --> Enterocyte Processing & Exit --> Removal in lymph and blood then to the liver ** NOTE: all carbohydrates enter the blood -------- In either a one-step or multi-step process, polymers that are digestible are broken down into a large number of monomers, which are absorbed across the epithelial cells of the absorptive part of the villus- these then transit across the basolateral membrane and are carried in the portal blood to the liver - sometimes one must first digest polymers into dimers and trimers- usually brush border enzymes then break the dimers into monomers for absorption proper using special apical transport proteins (many of these are secondary active transporters in which the nutrient comes in with sodium) *** KNOW THIS PATHWAY VERY WELL - also note that some di- and tri-peptides break the rule slightly and are absorbed into the cytoplasm prior to final digestion but what is noted above is by far the most common pathway

What are two drugs that can be used to treat othe GI issues?

Prokinetic Drugs: - Metoclopramide Other Conditions: - Pancrelipase

Functions of the Pharynx and Esophagus include:

Propulsive functions: - food transfer to esophagus from pharynx - UES allows entry of food into esophagus - esophagus transports bolus from pharynx to stomach - allows entry of food into stomach Protective effects: Upper Esophageal Sphincter - protects airway from swallowed material - protects airway from gastric reflux Esophagus - clears material refluxed from stomach Lower Esophageal Sphincter - protects esophagus from gastric reflux *** swallowing and vomiting, essentially, with upper and lower esophageal sphincters staying closed at all other times- want sphincters closed till time to eat

What is PDCAAS

Protein Digestibility- Corrected Amino Acid Score - high in animal proteins: eggs, milk protein, beef/poultry fish) - lower in plant proteins like kidney beans and whole wheat bread and also gelatin * gelatin is an exception to animal proteins having high PDCAAS because it is composed of collagen (made of 3 aa: glycine, hydroxyproline, and one more- so it is low in essential amino acids) * Protein sources that are well-balanced in AA composition to match the needs of the human body are "high quality"- and have a PDCAAS value near 1 * Protein sources that are misbalanced in essential AA have lower PDCAAS values * low quality protein sources can be mixed to provide a balanced intake Ex. supplement a wheat diet (high in the non-essential AA cysteine- with beans that are high in the essential AA Lysine) ----- Quality depends on PDCAAS- meats are high quality bc well balanced AA content to match needs of human body (milk and fish also) - gelatin is a POOR-quality protein bc of how it is composed of collagen - high in proline and glycine- NOT well-balanced for support of general protein synthesis

When comparing Acid-Reducing Drugs it is seen that

Proton Pump Inhibitors have the greatest effect of suppression overall and H2-Receptor Antagonists take longer to work but eventually decrease to as low as PPI levels but then gradually rises again later on *** H2-receptor antagonists have a significant effect on nighttime acid secretion BUT only a modest effect on meal-stimulated secretion - this is why an H2-receptor antagonist may be given at night with a PPI during the day- effective for patients who fail therapy with one drug alone *** PPIs have a significant effect on ALL acid secretion

In contrast to NaCl secretion from crypt cells that is low throughout duodenum to distal colon, intestinal bicarbonate secretion is HIGHEST in the

Proximal Colon: where many bacteria produce acid as a fermentation waste product - there is also moderate secretion at ileum and distal colon - there is NO significant secretion from duodenum or jejunum ----------- Early in GI of SI there is sufficient pancreatic and biliary bicarbonate to neutralize stomach acid. When later in the intestine there might be more need to buffer acids (ex from bacterial metabolism in the colon), the epithelial cells have the capacity to prodcue bicarb and secrete it into the lumen - as with other sources of acid or bicarbonate secretion, they are both produced at the same time using carbonic anhydrase (CA) then are secreted out diff. membranes - In this case, bicarb crosses the apical membrane into the lumen and H+ cross the basolateral membrane into the blood - H+, the other component produced by carbonic anhydrase, is traded with sodium across the basolateral membrane (secondary active transport bc the sodium that comes into the cell is then pumped across the basolateral membrane using the sodium-potassium pump) - The H+ goes into the blood and eventually interacts with blood bicarb which was itself a byproduct of gastric acid secretion ------ A limiting factor for this secretion is the availability of Cl- ions in the lumen, as the cell uses a chloride/bicarbonate antiport to achieve this apical bicarb secretion * in cystic fibrosis, the inability to secrete chloride ANYWHERE using the uniport CFTR results in shortage of Cl- ions in the intestinal tract so this compromises the bodys ability to secrete bicarb * in cholera there is no such limitation so combined with dehydration that already occurs, the high bicarb secretion into the intestinal lumen has the side effect of extra hydrogen in the blood- this could produce an acidosis in severe secretory diarrhea

Rectum and Anal Canal Venous Drainage

Proximal: - Superior Rectal vein --> Inferior Mesenteric vein (portal venous system) Middle: - Middle Rectal Vein --> Internal iliac vein (caval venous system) Distal (lower half of anal canal): - Inferior Rectal Vein --> Internal pudendal vein (caval venous system)

Treatments based of Vit A (retinol) include

Psoriasis Pro-myelocytic leukemia Acne

Barium Upper GI Exam "Barium Swallow"

Pt ingests barium orally to visualize the GI tract - Jejunum will have a "feather boa" appearance - In infants with malrotations the duodenum will not have its signature C shape - The ileocecal junction can also be seen on Barium study

Abnormal Pulse Pressures (pulse pressure= Systolic BP- Diastolic BP normally)

Pulse pressure is influenced by conditions that alter arterial compliance and/or stroke volume Pule pressure ~ stroke volume/ arterial compliance *** Knowing value of puls pressure will alert you to a possible change in vascular compliance or stroke volume ex. Arteriosclerosis (reduced arterial compliance) and Aortic Valve Stenosis (reduced stroke volume) - PP increases with arteriosclerosis bc arterial compliance decreases- walls of artery become stiffer (less elastic, less compliant)- so with the same SV, PP will increase ex. Aort (one of most elastic arteries due to its high levels of elastin)- during ventricular ejection the aorta is distended which will reduce the magnitude of the pulse pressure - a decrease in aortic compliance means the vessel is stiffer and distends less and therefore pulse pressure rises-- puts additional strain on LV as more work is required to eject same SV into less compliant aort --> ventricular hypertrophy and eventual heart failure- further with stiffening of coronary vasculature, blood flow to the heart will be decreased when work load of the heart is at its highest (ventricular systole) which will give sxs of coronary insufficiency (angina) PP decrease in aortic valve stenosis bc the narrowed aortic valve limitd the volume of blood that the LV can eject, thus decreasing stroke volume with no change in aortic compliance

Circular band of smooth muscle that is the junction between the stomach and the small intestine

Pyloric Sphincter ** Congenital hypertrophic pyloric stenosis: baby doing projectile vomiting and not thriving- may mean that the pyloric sphincter is too closed

Vitamin B6, Pyridoxine has various forms such as:

Pyridoxine (plants) Pyridoxal, Pyridoxamine (animal foods) * All above act as precursors for the active form, PLP Pyridoxal Phosphate (PLP) is the active form, enzyme cofactor for several dozen enzymes (it commonly binds proteins in this form): - decarboxylation (GAD- Glutamate decarboxylase: is an enzyme that catalyzes decarboxylation of glutamate to NT GABA and CO2) - cofactor for the ALA-synthase for heme synthesis - deamination (serine dehydratase) - transamination *** will be important in renal biochem - condensation reactions *** Isoniazid is a tuberculosis drug that reacts with B6: can cause an artificial deficiency in VitB6 by reacting with it- may need to supplement with B6 when given this drug

Vasculature of the Heart (it needs it own blood supply)

R and L Coronary Arteries: - these are the FIRST branches of the Aorta and arise from the Right & Left aortic sinuses ** these R and L each have their own branches Cardiac Veins - Great, Middle, and Small Cardiac Veins which all drain into the Coronary Sinus --> drains into R atrium of heart - Thebesian cardiac veins (not visible at gross level)

62 y/o women with h/o rheumatic heart disease presents with lower leg edema and distended abd & fluid accumulated in the abd cavity- she is most likely to have

R sided heart failure

Adult Derivatives of the aortic arch arteries

R/L First Aortic Arch - most of the arge degenerates - adult remnant= maxillary arteries R/L Second Aortic Arch - most degenerates BUT dorsal end forms the hyoid artery from which the stapedial arteries arise (stapedial artery is transientaly presetn in fetal life and connects the branches of the future external carotid artery to the internal carotid artery) R/L 3rd Aortic arch - R and L common carotid arteries - Internal carotid arteries - External carotid arteries branch off (this is not known for sure) R/L 4th Aortic Arch (ASYMMETRY) - L side becomes arch of aorta - R side becomes RIGHT subclavian artery (proximal segment of) - Distal portion derived from 7th intersegmental artery 5th Aortic Arch - Usually gives no structures R/L 6th Aortic Arch (AKA Pulmonary Arch) (ASYMMETRY) - R side froms the Right pulmonary atery, grows towards the lungs - L side forms the ductus arteriosus (known as ligamentum arteriosum after birth/closure) and some of left pulmonary artery

R/L Umbilical veins give rise to

R: degenerates early in fetal life L: Ligamentum teres

Tricuspid Valve allows communcaiton between

RA to RV

The stomach is found in the

RUQ and LUQ - pylorus of the stomach is in the RUQ ---- As for abd regions the stomach is found in the - epigastric region - left hypochondriac region - umbilical region

Pulmonary or Pulmonic valve

RV to pulmonary trunk

What is the greatest factor affenting the resistance to flow in the circular and longitudinal smooth muscle of GI:

Radius ! Increased radius= Increased flow - circular muscle shrinks radius, this greatly increases resistance to flow - longitudinal muscle slightly expands radius, so reduces resistance to flow (remember increased radius= increased flow) Radius^4th power (Poiseuille's Law)- pressure gradients drive flow, resistance stopes flow, and net flow only occurs if pressure gradient overcomes the resistance

Common Disease/ Pathologies presenting as Abd pain

Recall that clinical approach to EVERY patient is always: - history - PE - formulate a differential diagnosis - investigations and imaging - management plan (ex. treatment) For acute patients: Revert to the ABCs and resuscitate in order to stabilize before proceeding to deal with the chief complaint in the above order

Before you request imaging for your patient

Recall the clinical approach to every patient is always: - history - PE - formulate a differential diagnosis - investigations and imaging - management plane (ex. treatment) For acute patients: revert to the ABCs and resuscitate in order to stabilize before proceeding to deal with the chief complaint in the order above (A: airway, B: breathing, C: circulation)

Palpation & the clinical finding of Direct Tenderness

Recall: PAIN is a symptom described by pt vs. TENDERNESS is a finding elicited by the physician on physical exam - tenderness may be caused by inflammation of the abd wall, the peritoneum or viscus - a solid organ (ex. the liver) may be tender when its capsule is distended Palpate the abd in the area of tenderness while the pt raises his/her head off the pillow or feet off the table will provide valuble info about the source of the tenderness: - in these maneuvers the pt is actively contracting the parietal muscles, and the deeper organs are sheltered - if tenderness is diminished, then the source is likely a deeper structures - if tenderness is unchanged or worsens, a disorder of the abd wall is more likely

Left Atrium

Receives venous blood (RICH IN OXYGEN) from the 4 pulmonary veins (2 superior and 2 inferior) Internal aspect of L atrium: - LARGER smooth wall portion and smaller muscular portion that R. Atrium - Auricle (contains pectinate muscle) - Semilunar depression (floor of fossa ovalis). NOTE: that the valve of the oval fossa is the surrounding ridge

LDL uptake and regulation of cholesterol synthesis occurs via

Receptor Mediated Endocytosis LDL receptor: - cell surface glycoprotein - high-affinity, tightly regulated LDL/Receptor binding and internalization of the complex by endocytosis Release of Cholesterol inside the cells for: - utilization - storage as cholesterol ester - excretion ** Remember that in the liver, cholesterol regulated its on secretion via HMG CoA Reductase (Rate Limiting in Cholesterol Synthesis) and by regulating the [LDL receptors] on the surface

If defecation is NOT desired at the time that material enters the rectum, it is normal possible for

Rectal accomodation to occur - the rectum will relax and eventually when it next conracts its contents will be returned in an caudal-to-oral direction to the sigmoid colon - However, this is not guaranteed- sometimes there is so much waste in the colon and rectum that this is not possible (in this case, defecation will likely soon occur whether or not one desires to defecate bc the EAS isnt sipposed to hold back high-pressure waste by itself for hours at a time)

The ___ lies between the sigmoid colon and the anal canal

Rectum - fixed terminal part of the GI - follows the sacrococcygeal curve - internal surface features: rectal folds (partitions rectum to discrete portions- superior transverse, middly transverse, inferior transverse rectal fold) - primarily retroperitoneal at proximal part - INFRAperitoneal (subperitoneal) at distal part External surface has: - no haustra - no teniae coli (so this signifies it is NOT part of the colon) - no omental appendices

The colon terminates in the

Rectum - it is joined to the colon at an acute angle at the rectosigmoid junction (we relax this and straighten it out when its time to defecate) - the rectum is the final reservoir for fecal material (it is usually empty till we wanna fill it) * The internal anal sphincter is INVOLUNTARY, a thickened band of circular smooth muscle under autonomic control * The external anal sphincter is VOLUNTARY, made up of skeletal muscle under somatic nervous control (this is where the inner body meets the outter body) ------- By this point in the GI, masses being moved are usually solid which is why rectal valves are capable of holding the waste material in place proximal to the anal canal - when all sphincters are open and a pressure gradient exists between rectum and outside world, defecation will occur - more typically, the solid masses are held back in the sigmoid colon by the acute andle of the rectosigmoid junction, until defecation is desired or uncontrollable

Resistance to Flow (Jean Poiseuille)

Resistance to steady flow along a straight cylindrical tube is - proportional to tube length (L) and fluid viscoscity (n,eta) and - inversely proportional to tube radius raised to the 4th power -------- If we combine Poiseuilles definition of resistance with bulk flow law (remember CO=MAP/TPR) we can derive an expression for flow through a blood vessel: Flow= (P1-P2) x ((pi x r^4)/8nxL)) ** inverted bc CO= MAP x the reciprocal of TPR - flow is extremely sensistive to vessel radius - a fall in radius from 1cm (in aorta) to 0.01cm (in an arteriole) will increase resistance by a factor of 10^8- this is essentially why the arterioles are main site of resistance in the circulation *****Most effect way to control TPR (blood flow) is to regulate the radius of the systemic arteriole via vasoconstriction and vasodilation

Describe the structure of Resting vs. Active (Stimulated) Parietal Cells

Resting Parietal Cells: - Apical surface area is SMALL - Many tubulovesicles within cytosol which hold H-K pumps for later use Active (Stimulated) Parietal Cells: - Apical surface area is LARGE - Tubulovesicles fuse with membrane *** Canaliculus= name for apical membrane fused with vesicles - large number of H-K pumps available - hydrogen secretion capacity is increased

Total energy requirment is calculated by adding

Resting metabolic rate (RMR) (60%) + Thermia effect of food (10%) + Physical Activity (30%) - light- moderate normal activity: ~30-50% RMR needed in addition for activity - very active: 100% RMR extra needed - highly acitve: up to 800% of RMR need (if several hours of exercise/day- atheletes/physcial labor) *** less than 100% is more typical though ** thermic effect of food= energy required to breakdown food - thermic energy of food is 5-10% of total calories eaten (energy expended during digestion and lost for use by the body) Total caloric requirement= RMR + (0.3-0.5 up to >1) * RMR)/ 0.9 ex. A moderately active man weighs 75kg RMR= 71 x 1 x 24= 1800kcal/d physical activity= 50% RMR= 900kcal/d to account for thermic effect of food, the total RMR plus activity should be 90% of calories Total energy= (900+ 1800)/ 0.9= 3000kcal/d ** divide by 0.9 bc RMR and physical acitivyt account for the calories needed AFTER digestions (90% of the total calories needed) - so once we known RMR and physical acitivty, we divide that number by 90% to get the caloric requirement - another 10% of the intake is used in digestion (thermic effect of food) ** Physical activity provides the greaters variability in estimating diet

Congenital Pyloric Stenosis

Results from hypertrophy of the mainly circular muscle layer (splanchnic mesodermal in origin) in the pyloric region - narrow pyloric lumen thus impedes passage of food After feeding- the stomach becomes distended and projectile vomiting occurs * Vomiting usually begins in 2nd week of life - The Milk is sometimes curdled in appearance, bc as the milk remains in the stomach and does not move forward to the small intesting, the stomach acid "curdles" it - this is 4x more common in boys - occurs apprx 1/200 liver births Signs and Sxs: - infrequent stools - dehydration and loss of subcutaneous fat - pyloric mass after a test fee Tretment - Surgical: remove excess tissues and it does not grow back

Vomiting (Emesis) starts in the gut with ____ peristalsis

Retrograde peristalsis (antiperistalsis): - resulting in a highly programmed action of respiratory and digestive systems resulting in ejection of materials through the pharynx and oral cavity Caused by: - gastric or upper intestinal irritation - vestibular function/stimuli- motion sickness - gastric outlet constriction This is preceded/accompanied by nausea, other signs (ex. pallor) - process involves first supressing normal peristalsis, with a possible antiperistalsis moving intestinal contents into the stomach - then powerful abd. skeletal m. contraction generates a strong pressure gradient for emesis - relaxation of BOTH esophageal sphincters and the esophageal wall allows the contents to pass through the esophagus into the oral cavity

Pancreas fuses to the dorsal body wall to become

Retroperitoneal - When Dorsal and ventral pancreatic buds fuse in development their ductal systems become interconnected - Main pancreatic duct (AKA Duct of Wirsung) formed from distal portion of dorsal pancreatic duct and ALL of the ventral pancreatic duct - Accessory pancreatic duct (AKA Duct of Santorini) IF PRESENT is formed from the proximal portion of the DORSAL pancreatic duct - Main pancreatic duct (pluse bile duct enters into duodenum at major duodenal papilla (Ampulla of Vater)

Where does the RCA supply vs LCA

Right Coronary Artery supplys most of the myocardium on the right: - SA nodal: SA node and pulmonary trunk - AV nodal: AV node - Right marginal: Right ventricle - Posterior Descending Interventricular: Posterior third of the IVS and R and L ventricles Left Coronary Artery supplis most of the Left hand side: - LAD: anterior Right and Left Ventricles - Diagonal branch: anterior left ventricle wall - Septal: does the anterior 2/3 IVS and bundle of His - Circumflex: Left border, posterior aspect of the Left Ventricle **NOTE: BOTH supply the mdiline interventricular areas

Describe the flow of bile through the biliary tree

Right and Left hepatic duct join to become the Common Hepatic Duct from here it can to the gallbladder to be stored OR to the Common bile duct * the Common bile duct (via sphincter of bile duct) and the pancreatic duct (via sphincter of main pancreatic duct) meet in the duodenum at the hepatopancreatic sphincter (of Oddi)

Nutmeg liver can be seen in

Right heart failure ** liver will have light areas and dark fibrotic areas ** chronic passive congestion ** areas of central veins tend to become congested and there can be hemorrhage and even infarction in these area and extend outwards

The cystic artery orginated from the

Right hepatic artery (NOTE: there are variations in where the cystic artery branches off of and these are of clinical importance) ** cystic artery gives the blood supply to the gallbladder

Irritable Bowel Syndrome (IBS)

Rome IV Criteria for Diagnosing IBS: Recurrent abd pain occuring, on avg. at least 1 day/week in the last 3 months, associated with 2 or more of the following criteria: - related to defecation - associated with a change in freq. of stool - associated with a change in form (apperance) of stool ** Criteria fulfilled for at least 3 month and symptom onset at least 6 months prior to diagnosis ----- Other common features may include (symptoms & signs) - altered bowel habit - abd distension - feeling of incomplete defecation - passage of mucus per rectum - pain is often exacerbated by eating or emotional stress and improved by passage of flatus or stools ----- Female pts with IBS commonly report worsening symptoms during the premenstrual and menstrual phases - IBS can also be precipitated by excessive stress ** Bleeding per rectum, loss of weight, nocturnal diarrhea, severe constipation or diarrhea, hematochezia, fever, precludes a diagnosis of IBS (should NOT occur with IBS) * In a pt with IBS- Diarrhea is more common in men, constipation is more common in women

In the intestinal phase of pancreatic secretion: Acid is detected by

S cells in the duodenum which secrete Secretin - Secretin stimulates duct cells (some afffect on acinar, but mostly on duct) by acting on their recptors and sitmulating HCO3- secretion - The receptors on the luminal membrane of S cells detect acid, typically below pH of 4.5. When stimulated by acid, S cells secrete the hormone secretin into the blood. Secretin has its most important effects at the pancreatic ducts, greatly increasing both bicarbonate and fluid secretion into the ducts. This helps create a pressure gradient to "wash out" the enzymes etc. from acinar fluid into the duodenal lumen. Ultimately when digestion and absorption remove the fat and protein, and acid has been adequately neutralized by bicarbonate, both I cells and S cells will cease activity and the intestinal phase will be over.

Proton-pump inhibitors can be used clinically for

SEVERE FORMS of Gastroesophageal Reflux Disease and Peptic Ulcer Disease (PUD) due to their superior acid inhibition (inhibit 90-95% secretion) - PPIs are the most effective treatment for nonerosive and erosive reflux disease, and esophageal complications of reflux disease (peptic stricture and Barrett's Esophagus) - In PUD it provides rapid symptom relief and faster ulcer healing compared to H2 antagonists ** Can also be used for prevention of bleeding from stress induced Gastritis (in critically ill patients) ** it is the ONLY effective drug option in Hypersecretory Conditions like Zollinger-Ellison Tumor in the pancrease: patients with isolated gastrinomas are best treated with surgical resection. In patient with unresectable gastrinomas PPIs achieve excellent acid suppresion

Tranporters for Carbohydrates into enterocytes are mostly

SGLT-1 (sodium dependent glucose transporter) but there is also GLUT-5 on brush border that takes up fructose ------- More than one glycosidase is needed to limit digest a dietary saccharide - most digestion is by pancreatic amylase - enterocytes have anchored glycosidases for digestion in close proximity to transporters that facilitate absorption Transporters are available for uptake of sugars in the intestine - Upregulation of transporters occur with exposure to carbohydrates (sweet-taste receptors and enteroendocrine signaling) * GLUT transporter is what allows for development of sweet taste ------- Each sugar is absorbed by a specific transporter, some sugar transporters are symporters

increased physical activity has an SNS effect and local effect

SNS: increased SNS --> increased CO which increases MAP and also increased SNS leads to systemic vasoconstriction --> increases TPR local: massive vasodilation in exercising muscles (local control) --> decreases TPR OVERALL : reduction in TPR -- so diastolic pressure will remain unchanged (or decrease slightly) during exercise * Vasodilation in skeletal m. (active hyperemia) such that most of the elevation of CO is directed to skeletal muscles MAP increased by only 15-30 mmHG during exercise

Baroreceptors are sensitive to increases and decreases in _____ of the blood vessel walls

STRETCH

The ___ is part of the male external genitalia and is a cutaneous, muscular sac that has a variable (wrinkled) appearance

Scrotum - The rugose (wrinkled) appearnace is due to smooth muscle fibers known as Dartos Muscle (helps with temp regulation) that are extremely thin and insert into skin - The scrotum can protect the testes by regulating temperature (as it can decrease the exposed surface area of skin (cremaster muscle can help) * the scrotum develops from 2 lacioscrotal swellings which fuse to form a pouch: - divided internally by the Scrotal Septum (continuation of the Dartos Fascia) - demarked externally by the Scrotal Raphe

What do the pancreatic exocrine secretions consist of? How much is secreted each day?

Secretion ~ 1.5 L/day (1500ml/day) can come from acinar or ductular Acinar: enzymes and other proteins & peptides - proteases (proteins) - lipases (fats) - amylase (carbohydrates) - nucleases (nucleic acids) - trypsin inhibitors **some of these are secreted in an inactive form so that they do not digest the pancrease Ductular: ions and water - HCO3-: neutralizes gastric acid and creates optimal pH for digestive enzymes --------- NOTE: main function of exocrine pancreas is to secrete a pancreatic juice that is rich in both bicarbonate (to neutralize stomach acid) and in an assortment of active (ex. lipases) and inactive (ex. trypsinogen) digestive enzymes, along with water and sodium

Describe the secretory portion (S) of the Major Salivary glands

Secretory portion is composed of serous and/or mucous secretory cells arranged in acini and are surrounded by myoepithelial cells (aka basket cells) 1. Parotid: purely serous cells (basophilic) - high in adipose cells - can see striated and intercalated ducts - secretory granules seen in the serous acini- which contain digestive enzymes - plasma cells sometimes present (these cells produce immunoglobulines taken up and re-secreted by acinar cells)- can get immuno protectors out into saliva 2. Submandibular- MIXED, predominantly SEROUS secreting, distinctive serous demilunes (half-moon shaped cells) - less adipose cells than in the parotid gland - excretory ducts can be seen - some mucous acini - striated ducts also present 3. Sublingual- MIXED, predominantly MUCOUS secreting (pale staining, white), with occasional serous demilunes - almost ALL mucous acini surrounded by serous demilunes ** lumen connected to outside of body - epithelial side is facing the lumen

Hypovolemic Shock (hemorrhage)

Shock is a severe reduction in blood supply to the tissues and can be precipitated by a variety of circumstances Caused by drop in blood volume due to: - hemorrhage - dehydration - severe diarrhea or vomiting - burns

Abdominal Exam: 2. Auscultation

Should be performed before percussion and palpation - auscultate in the 4 quadrants - presence or absence of bowel sounds indicate presence or abscence of peristaltic activity - bowel sounds best heard with the bell of the stethoscope - normal bowel sounds a "gurgling" and the normal freq. is 5-35/minute, depending on timinig since the last meal and other factors - if auscultatory finding are normal in one region in an asymptomatic patient, this is usually considered an adequate assessment -- NOTE: - Complete absence of bowel sounds is ALWAYS abnormal and could be due to peritonitis - Absence of bowel sounds can only accurately be concluded after listening for a full 2 minutes - High-pitched tinkling and rushing bowel sounds may be present in diarrhea, partial intestinal obstruction

The ___ is the fifth part of the large intestine and connects the descending colon to the rectum

Sigmoid Colon - in LLQ - extends from the iliac fossa to apprx. S3 vertebral level - characterized by S-shaped loop - intraperitoneal organ (mobile) - teniae coli terminated at the rectosigmoid junction (apprx. 15cm from the anus) - Sigmoid arteries which are direct branches of the inferior mesenteric artery

What is called when portion of all of a diaphragm of heart border is obscured by fluid density on XRAY of cehst

Silhouette Sign

Left Ventricle

Similar to the right ventricle structures - Trabecular Carneae (rought portion) - Aortic vesitbule (smooth portion) - Bicuspid (Mitral) Valve (**** remember R ventricle had the Tricuspid Valve "RighT ends in T"): chordae tendineae AND papillary muscles (2): anterior and posterior ** THICKER wall (myocaridum) that R ventricle (bc blood from L. ventricle must be pushed aroun systemic circulation- the R ventricle only pumped to pulmonary circulation)

Folate Biochemistry

Single-Carbon pool donors - serine --> glycine - glycine --> NH3 + CO2 (glycine cleavage enzyme) - FIGLU is a degradation product of histidine, formiminoglutamate; this leads to Formimino-THF NOTE: - for donating methyls, either serine or glycine is used, not both at once - serine and glycine can be broken down in the reaciton of THF to 5,10N-methylene-THF (they can also be used for the synthesis of glycine and serine)- the reactions lie near equilibrium and are reversible by mass action - FIGLU is formiminoglutamate- it is formed from breakdown of histidine. The N5-formimino-THF can be convereted to either 5,10 methylene THF or N10-formyl-THF ------- MTHFR: The rection 5,10N-methylene-THF --> 5-methyl-THF is biologically IRREVERSIBLE (highly exergonic). This is why the following methionine synthase reaction is so important- without it, folate gets trapped as 5-methyl-folate and cannot be reconverted to THF ("folate trap" ) --- Methionine synthase - is an enzyme that uses B12 as a cofactor - it catalyzes the synthesis of methionine from homocysteine - the added methyl group comes from 5-methyl-THF The net reaction: Homocysteine + 5-methyl-THF --> Methionine + THF --- These whole processes can lead to: - methylation of DNA/RNA, lipids and proteins - Purine Synthesis - thymidine synthesis ** see Vitamins Part 1 pwrpt Slide 31

Which capillaries have holes in its basment membrane

Sinusoids have an incomplete basement membrane and intercellular gaps in its endothelial tunica intima layer

Movement of Lymph

Slow as there is NO "Lymphatic heart" Flow of lymph is supported by: - unidirectional flow of lymph vessels are blind ended, feature overlapping endothelial cells and posssess valves - contraction of smooth m. in walls of larger vessels - skeletal muscle pump - pulsations from local arteries

Describe the consequences of flow rate on Saliva Composition

Slowest Flow: - efficient duct reabsorption of sodium (apprx 90% and chloride) - bicarbonate is LOW - potassium concentrations are at the highest - saliva is VERY hypotonic Fastest Flow - inefficieny duct reabsorption of sodium and chloride - bicarbonate is ELEVATED - saliva is somewhat hypotonic ---------- Involves 4 ions- Their typical values are: 145 mEq/L for Na+ 105-110 mEq/L for Cl- 24 mEq/L for Bicarbonate (HCO3-) 3-5 mEq/L for K+ --- Bottom line - There is VERY efficient NaCl absorption at LOW secretory rates and LESS efficent at HIGH secretory rates - Bicarbonate secretion rises to levels higher than plasma when flow rates INCREASE past baseline

Ileocecal Sphincter is the junction of the

Small and large intestine it is the "end" of the small intestine, where the terminal ileum meets the cecum In the ileum: - pressure and chemical irritation relax the sphincter and excite peristalsis - fluidity of contents promotes emptying (stretch receptors from ENS) In cecum: - pressure or chemical irritation inhibits peristalsis of ileum and excites sphincter to close NOTE: the terminal ileum is not very good at absoprtion (maybe just a few vitamins and bile/soap products youre recycling/use again)

Mucosal patterns of small bowel vs. colon

Small bowel: Valvulae conniventes (plicae circulares)- folds continue all the way across the bowel ** Small bowel obstruction on plain radiography of abd looks like a wifi signal Large bowel: Haustra (folds are discontinuous across the colon, due to taenia coli) *** Large bowel obstruction would look larger and span across the abd

Dietary Fiber: nondigestible carbohydrate polymers (cellulose and otehrs) or lignin (a cell wall component made of aromatic rings and sugars- cross-linked phennolic polymers) can be either

Soluble or Insoluble Soluble: resistant to digestion (NOT digested) by intestinal enzymes, but may be partially fermented to short chain fatty acids by bacteria in the colon. Supplies few calories ex. pectin, agar, alginate (cell wall of algae), polydextrose (synthetic), lactulose Insoluble: NOT digested at all and is excreted ex: cellulose, lignin, chitin, gum, also includes resistant starch (high amylose corn starch, raw bananas, uncooked pasta and potatoes) Functional fiber: synthetic or modified fiber, added to foods Good fiber sources: Bran, navy beans, shredded wheat, cranberry beans, lentils, peas Health Effects of fiber include: - reduces constipation and hemorrhoid formation, softens stools - increases bowel motility, thus reducing exposure of gut to carcinogens - decreases absorption of dietary fat and cholesterol, increases fecal loss of cholesterol - delays gastric emptying, generates sensation of fullness, reduces postprandial blood glucose concentration ** typical values for these items and many other beans is about 7.5-9.5g fiber per portion. Most portion sizes are about 1/2 cup and yield ~20-30g carbs

Pericardial Cavity

Space between Parietal and Visceral layers of Serous Pericardium ***Pericardial Fluid is contained within the pericardial cavity - it is secreted by serous mesothelium *** this is linked to Cardiac Tamponade

External Intercostal Muscles

Span from the rib tubercles to the costochondral junction - muscle fibers run inferoanteriorly from rib above to the rib below ("hands in pocket" orientation) ** anteriorly in portion that is not covered by muscle you fine the external intercostal membrane

Internal intercostal muscles

Span from the sternum to the angle of ribe - muscle fibers run inferiorposteriorly - run deep and right angeles to the external intercostal muscle fibers ** part in back that is not covered by muscle is covered by the internal intercostal membrane

Blood-Brain barrier

Special type of continuous capillary that functions to protect the brain - allows essential metabolites (such as oxygen and glucose) to pass from the blood to the brain, BUT blocks most molecules bigger than 500 daltons (such as hormones, NTs, viruses and bacteria and drugs) - composed of extensive tight junctions between capillary endothelial cells - extensive tight junctions due to the presence of astrocytes (type of glical cell) - astrocyte foot processes wrap around endothelail cells and astrocytes secrete factors that induce capillary endothelial cells to produce extensive tight junctions

Hepatic Sinusoids are

Specialized Capillaries that carry blood through the liver parenchyma These Hepatic Sinusoids have 3 associated cell types: 1. Endothelial Cells - make up a discontinuous sinusoidal endothelium with discontinuous basal lamina (substances can pass through) 2. Ito Cells - FAT storing stellate cells in the space of Disse - Store VitA within cytoplasmic lipid droplets - Secrete Type III collagen in the space of Disse and growth factors for new hepatocytes ** Ito cells become myofibroblasts after liver injury and tend to produce fibrotic scar tissue seen in liver damage from cirrhosis 3. Kuppfer Cells - Numerous specialized stellate macrophages, usually called Kuppfer cells, are found within the sinusoid lining - are derived from monocytes and belong to the mononuclear phagocytic system - these cells recognize and phagocytose aged erythrocytes, freeing heme and iron for reuse or storage in ferritin complexes - they are also antigen-presenting cells and remove any bacteria or debris present in the portal blood

The ___ suspends the testis in the scrotum and contains the structures that run to and from the testis

Spermatic Cord * NOTE: The spermatic cord - Begins at: Deep Inguinal Ring ("internal") - Travels through: Inguinal Canal - Emerges at: Superficial Inguinal Ring ("external") - Ends in: Scrotum (Posterior Border of the testis)

What enzyme is deficient in Niemann-Pick disease

Sphingomyelinase - Sphingomyelin accumulates in spleen, liver, lungs, bone marroow and brain Sxs: Type A (infantile)(neurological type): jaundice, characterized by hepatomegaly, profound brain damage, retarded growth, progressive degeneration of NS, death within 18months-2yrs (severe) Type B (teens)(non-neurological type): large liver and spleen, not very severe- about 10% normal levels of sphingomyelinase is present- other health complications like enlarged liver, spleen, resp. problems etc. exist, elevated cholesterol and other fats in blood Type C/D (adult): moderate enlargement of spleen and liver; extensive brain damage * bone marrow transplant * autosomal recessive disease * common in jewish populations ----- Pts produce a defective form of lysosomal enzyme sphingomyelinase which under normal conditions breaks down sphingomyelin by cleaving its phosphocholine head group * the defective enzyme is unable to breakdown and the metabolic turnover rate is affected with sphingomyelin accumulates in tissues principally in brain and also liver, spleen, lungs, etc Sxs: - enlarged liver, spleen due to abnormal accumulation of membrane lipids - mental retardation due to degeneration of the brain tissue, seizures, often slurred speech - lack of muscle coordintaion, dystonia (difficulty moving limbs), paralysis of the eye

The most commonly injured abdominal organ is the

Spleen (SPLENIC RUPTURE) - Despite being protected by the rib cage, a traumatic blow to the LEFT side may fracture the ribs (ribs 9,10,11) and result in fragments of bone lacerating the spleen Ex. Could be becoming impaled against the steering wheel during a road traffic accident If the spleen ruptures this will lead to: - shock - intraperitoneal hemorrhage (profuse internal bleeding) bc of the large splenic A. ------ Splenectomy: surgical removal of the spleen to prevent bleeding to death Splenomegaly: pathological enlargement of the spleen (up to 10x normal size) accompanied by high blood pressure - normally you remove the spleen in these cases

What are the 3 Stages of Severity of GERD and the medical management for each?

Stage I: Sporadic uncomplicated heartburn, often in setting of known precipitating factor. Often not the chief complaint. Less than 2-3 episodes/week. No additional symptoms Mangement: lifestyle modification, including diet, positional changes, weight loss, etc. Antacids and/or histamine H2 receptor antagonists as needed Stage II: Frequent symptoms, with or without esophagitis. Greater than 2-3 episodes/week Management: Proton pump inhibitors more effective than histamine H2 receptor antagonists Stage III: Chronic, unrelenting symptoms; immediate relapse off therapy. Esophageal complications (ex. Stricture, Barrett's metaplasia) Management: Proton pump inhibitor either once or twice daily

Supine to standing

Stand up from supine position --> gravity pools blood in legs --> decreasee central venous volume and pressure --> decrease venous return which decrease CO --> decrease MAP (and syncope) --> decrease baroreceptor activity --> works in brainstem to decrease NTS activity (increases vasomotor activity (SNS), decreases cardioinhibitory activity (PNS) -- increasing HR, TPR and increased contractility which increases stroke volume increase SV and HR increase cardiac output and this can counteact a reduced CO and venous return ***** in case of hemorrhage- flow chart would be same but begin at decreased central venous volume and pressure

What forms the anterior part of the thoracic cage, protecting the Superior Mediastinal Structures?

Sternum 3 parts: 1. Manubrium - broad quadrangular superior part of the sternum - articulates with clavicle at the sternoclavicular joint * Manubriosternal joint (Sternal Angle or Angle of Louis= 140 degress) 2. Body - Has lateral costal notches (attachments for the 2nd-7th ribs) 3. Xiphoid Process - Corresponds to T10 vertebral body - Xiphisternal joint: marks the inferior limit of the heart, ventral thoracic cavity, superior limit of the liver & the anterior attachment of the diaphragm

Chloride Secretory Diarrhea

Stimulation of the parasympathetic nerves cause release of VIP -> increase cAMP --> increase activity of CFTR channels (ACh has also been shown to acitivate this via phospholipase C activity but VIP is major stimulator) - this is can be caused by some bacterial toxins and some laxatives leads to increased Cl- secretion and diarrhea - increased entry of cholride into lumen --> hyperpolarization of transepithelial potential difference- lumen becomes more negative - increasing driving force for Na+ entry and water follows ---------- Sympathetic stimulates--> release neuropeptide Y --> inhibits cAMP production --> decreases Cl- secretion --> depolarization of transepithelial potential difference --> decrease Na+ entry and water movement ------- This same cAMP system can be HYPERACTIVATED by certain drugs which act as laxatives or by a variety of bacterial toxins that bind to receptors coupled to cAMP system (ex. toxins released by vibrio cholerae) - secrete two toxins one that activate cAMP system and one that makes the tight junctions leakier ---- - excess cGMP can also cause increase cl- and lead to diarrhea (not as potent as cAMP)

List the levels of vertebrae that are common areas of referred pain

Stomach --> T6-T9 (upper back) Small intestines --> T8-T10 Appendix --> T10 (umbilical region) Ascending & Transverse colon --> T10-T11 Proximal descending colon --> T12-L1 Distal descending colon --> L2-L3 Rectum --> S2-S4

Formation of the Stomach

Stomach first apparent as Fusiform (tapering at both ends) dilation of the foregut - the Dorsal Wall undergoes rapid growth to give the Greater Curvature - then there is a rotation of the stomach 90 degrees clockwise around its longitudinal axis Results in: 1. Ventral border (lesser curvature) moving to the right. Dorsal border (greater curvature) moving to the left 2. Dorsal mesentery moves to the left to give the Greater Omentum. Ventral Mesentery to the Right to give the Lesser Omentum 3. The right side becomes dorsal and carries the R vagus to the dorsal side (posterior). The left side becomes ventral and carries the left vagus to the ventral side (anterior) -- these become anterior and posterior vagal trunk Stomach ALSO rotates around an anteroposterior (AP axis) which results in - caudal (pyloris) portion moves upwards (and to the right) - cephalic (cardia) portion moves downwards (and to the left)

Small intestine begins as the ____ ends

Stomach! at the Gastroduodenal Junction stomach= simple columnar with gastric glands

Pylorus (AKA gastroduodenal sphincter) is the beginning of the intestinal tract. In general it provides resistance to flow in either direction. What tends to open it vs what tends to close it?

Stomach-based factors tend to OPEN PYLORUS - you have to empty the stomach sometime - ex: gastric stretch, acid Duodenum-based factors tend to CLOSE PYLORUS - if materials are already in duodenum, they need time to be digested and absorbed- so pylorus usually closed till nutrients are gone * Can be thought of as one component of a coordinated antroduodenal cluster to control gastric emptying

Inflammatory Bowels Disease (IBS) is Autoimmune it can be characterized by

Sub-Acute OR Chronic- Inflammation 2 Main Forms: Ulcerative Colitis and Chrons Diseases *** which can differe in the areas of the bowel they affect & sometimes are hard to differentiate so are just termed IBS Ulcerative Colitis: - usually confined to the mucosa ONLY (exudate of pus, blood, and mucous from the "crypt abscess" - damage and breakdown of lining of mucosa - collection of polymorphs in glands as they increase - always starts in rectum (up to 1/3 dont progress) - limited to colon and rectum Diagnosis: - continuous lesions - rare - lead pipe colon appearance due to chronic scarring and subsequent reaction and loss of haustra Complications: - Perforation - Stricture - Megacolon (increased dilationg of bowel and paralysis leading to obstruction of bowel) - cancer due to long standing inflammation Crohns Disease: - infalmmation extends full thickness of the bowel, involves ALL bowel layers which is what may lead to fistulas and abscesses - shows signs of chronic inflammation (histiocytes fusing and forming giant cells & localized collectiong of inflammed cells (lymphocytes & histiocytes "granulomasas) - ulcers run deeper and are called fissures rather than simple ulcers - rectal sparing in 50% - May affect mouth to anus (but seen mostly in esophagus) Diagnosis: - Skip lesions: interspersed normal and diseased bowel - Aphthous ulcers & fissures - Cobblestone appearance from submucosal thickening interspersed with mucosal ulceration Complications: - Abscess - Fistulas - Obstruction - Cancer (less common than as seen in Ulcerative Colitis) - Perianal disease (associated with fistula formation)

Differences in what layer allows for the differentiation of the small intestine

Submucosa It is a layer of: - Dense irregular CT - Blood vessels and nerves (including Meissner's Plexus), lymphatics In duodenum it has --> BRUNNERS GLANDS - tubuloacinar glands found in the submucosa of the duodenum - secretion is clear ALKALINE mucin (pH 8.2-9.3), empty secretion into the neck of crypts - alkaline protection against acid chyme (protects the lining of the stomach) - creates optimal pH for pancreatic enzymes In ileum it contains --> PEYERS PATCHES (PP) (aggregated lymph nodules) - more prominent distally within the ileum - aggregations of lymphatic tissue (Gut associated lymphatic tissues): GALT system ** therefore germinal centers can be seen - covered by M (microfold) cells - important in immune response

Sudden cardiac death (SCD)

Sudden and unexpected death within 1 hr after appearance of symptoms if caused by a cardiac disease

Myocardial Infarction (MI)

Sudden occlusion of a major artery (by an embolus) - Region of heart supplied by occluded vesesl become INFARCTED (rendered bloodless) and becomes NECROTIC (tissue death) * Most common cause of MI= Coronary artery insufficiency from artherosclerosis 3 Most Common Sites of Occlusion: 1. LAD (Anterior Interventricular Artery): 40-50% 2. Right Coronary Artery: 30-40% 3. Circumflex artery: 15-20%

Lymph from the skin of the scrotum initially drains to the

Superficial Inguinal Lymph Nodes

Exit of the Inguinal Canal is the

Superficial Inguinal Ring (AKA "external" inguinal ring) - triangular opening in the external oblique aponeurosis - located superolateral to the pubic tubercle - MEDIAL to the inferior epigastric artery and vein

Cancer of the vulva can begin in the external sex organs (ex. Labium Majus)- it drains to the

Superficial inguinal l.n first - lymphatic vessels drain the skin of the perineum

Sternal Fracturs can cause injury to the

Superior Mediastinal structures, heart & major vessels, and lungs (if the fracture goes postero laterally)

The Hepatic Portal Vein forms when which two veins unite?

Superior Mesenteric Vein and the Splenic Vein

Clinical features of congestive heart failure

Sxs: - dyspnea/breathlessness - fatigue/tiredness Sings of venous congestion: - pulmonary circuit: pulmonary edema - systemic circuit: peripher edema Structureal and/or functional abnormalities Ex. LV(hypertrophy)/dilation

Sources of VitB12, Cobalamin

Synthesized only in bacteria, NOT in plants. The rarest of vitamins - only available from animal products: liver, red meat, eggs, dairy, and enhanced cereals (strict vegans may be at risk for deficiency: but we store a lot fo VitB12 so it may take a while to notice a deficiency) Deficiency: Results in Pernicious Anemia (Macrocytic like folate), typically from mal-absoprtion - the anemia is partly bc of B12s role in salvaging methyl-THF back to folate via the methionine synthase reaction - later stages show neuropsychiatric symptoms (bc methylmalonyl CoA mutase doesnt allow for breakdown of certain AA) FOLATE WOULD NOT HAVE THESE NEUROPSYCHIATRIC SYMPTOMS! - RDA is 2.4microg, but several (2-5)mg are typically stored, thus deficiency may not be apparent for a long time ----- Pernicious Anemia Sxs: - skin tingling- parasthesia - tongue soreness- glossitis - fatigue - pernicious anemia is a type of megaloblastic/macrocytic anemia Can also include: - depression - low grade fever - diarrhea - dyspepsia - weight loss - neurophathy - jaundice - cheilitis * eventually: cognitive impairment, CNS effects may occur in absence of anemia Treatment: intramuscular injections of cyano-cobalamin or high oral doses

Systemic Venous System (AKA Caval System) vs. Hepatic Portal Venous System

System Venous System (AKA Caval System): - veins that drain deoxygenated blood DIRECTLY towards the heart - sometimes referred to as "Caval" system as it involves the superior & inferior vena cava Hepatic Portal Venous System: - veins that drain nutrient rich deoxygenated blood from the intestines and the spleen DIRECTLY towards the liver *** REMEMBER: the liver is unique in that is receives BOTH oxygenated and deoxygenated blood--> from the proper hepatic artery and hepatic portal vein respectively

Systolic vs Diastolic Dysfunction

Systolic Dysfunction: Due to reduced ability to contract or eject blood can be L or Right heart Causes: - reduced contractility (ex. MI) - increased apparent afterload (ex. chronic aortic valve stenosis) - uncontrolled systemic hypertension Diastolic Dysfunction: Due to reduced ability to relax or fill the ventricle Can be L or R heart Causes: - reduced ventricular compliance (ex. caused by concentric hypertrophy) - reduced chamber volume and reduced EDV and SV - reduced preload (ex. mitral valve stenosis) *** "diastolic dysfunction" refers to changes in ventricular diastolic properities that have an adverse effect on stroke volume

Thoracic Wall Dermatomes

T1-T12 - strip-like segmental innervation of thoracic wall by intercostal nerves * important in describing regional damage and things like Herpes Zoster locations which stay in a dermatome Some Key areas: T4: nipple area T6: Xiphoid process T8: costal margin T10: umbilicus

The esophagus travels through the esophageal hiatus of the diaphragm at the level of

T10 - Esophagus is attached to the diaphragm by the phrenico-esophageal ligament - Terminates at the cardial orifice of the stomach (Juction (Z-Line)) of esophageal mucosa and gastric mucosa) At this abdominal part of the esophagus: Arterial Supply: esophageal branches from the L gastric artery Venous drainage: L gastric vein --> portal venous system and the Esophageal veins --> systemic venous system (via azygous v.) Lymphatics: L gastric lymph nodes --> Celiac lymph nodes Innervation: - Parasymp--> Vagus (CNX) ** remember that stomach rotates 90 degrees clockwise in development and the R and L Vagus Nerves become the Anterior and Posterior Vagal Trunks which supply the Parasymp. Innervation - Sympathetic --> Greater Splanchnic Nerve (T5-T9)

Celiac Trunk branches from the abdominal aorta ar the level of

T12

Subcostal nerves (on L and R) are formed by the anterior rami of

T12 - these nerves stem from the anterior rami of the 12th thoracic spinal nerves - subcostal nerves innervate the abd wall muscles and the skin (via cutaneous branches) - between the iliac crests and the umbilicus

Descending aorta pierces the diaphragm at

T12 to enter the abd

aortic arch ends at

T4 ** trache terminates around T4-T5 into 2 main bronchi

Sternal Angle (Angle of Louis) is at the level of

T4/T5 It is an important anatomicl landmark as it serves as: 1. Separation between superior and inferior mediastinum 2. Beginning AND end of the aortic arch 3. Bifurcation of the trachea into 2 R and L primary bronchi 4. Azygos vein arches over the rood of the RIGHT lung and opens into SVC 5. The upper limit of the base of the heart (AKA upper border of the atria of the heart)

LaPlaces Law and Aortic Anuerysm

T= (Pi-Po) x r increased radius --> increased tension --> increased radius --> increased tension eventually point to where it will rupture ** once an aneurysm begins to form, it progresses inexorably ** increased wall tension further thins and weakens the wall increasing vessel radius and further increasing wall tension- this positive feedback will eventually lead to rupture if not treated ** treat with a stent graft- place via catheter use *** catheter introduced via the femoral aa. and the stent graft guided to location of the anuerysm ** blood flows through the stent graft which decreases the pressure on the wall of the weakend artery and therefore decreases wall tension so the aneurysm doe not rupture

T or F: Chylomicrons interfere with measurements of LDL cholesterol, which is utilize total TAGs as part of calculation

TRUE! Therefore, typical lipid panels are done after overnight fasting to remove chylomicron interference from the measuremnet of LDL cholesterol

T or F: the Direction of blood flow in the liver is OPPOSITE to the direction of bile flow

TRUE! - Blood flow: periphery --> center - Bile flow: center --> peripher

T or F: the vasculature is being remodeled simultaneously with heart development

TRUE! - Venous return from the body and placenta enters into the RIGHT atrium * Vascular remodeling shunts venous return into the newly developed venae cavae (IVC( thus emptying into the Right atrium) - these vascular changes influence the development of the sinus venosus - in weeks 4-5 there is Left to RIght shunting of blood in the venous system

T or F: the Gallbladder DOES NOT have a submucosa

TRUE! - the absence of submucosa and or muscularis mucosae facilitates identification of the gallbladder

T or F: Misoprostol has a Black Box Warning

TRUE! Black Box warning for administration to women who are pregnant- it can cause abortion, premature birth, or birth defect (PREGNANCY CATEGORY X- completely contraindicated in pregnancy) Pharmacokinetics: - oral, vaginal, rectal - rapid oral absorption - extensively deesterified to active form - duration of effect= 3 hours - renal elimination Adverse effects: - diarrhea and abd pain - increased uterine contraction - relatively contraindicated in women of child bearing age (must be counseled and report back if they become pregnant) - pregnancy category X (refer to whats listed above) - no major interactions Clinical Uses: - Prevention of NSAID induced ulcer (ppl more commonly use PPI now though)

T or F: Fluoride is NOT a naturally required mineral

TRUE! The normal hydroxyappetite formed to make bones (calcium phosphate), can have the hydroxyl group replaced for form a fluorapatite - However, whether this is the principal mechanism is for reducing dental karies is under dispute - The other potential mechanism is inhibition of the enzyme enolase in bacteria in the mouth * Fluoride treatments may affect the growth of tooth enamel - Fluoride is used for hard bones and teeth - It can be found in Water - Its deficiency can be seen in cases of tooth decay ** Remember fluoride is known to inhibit enolase (is this what prevents dental karies?)

T or F: improvement is a moving target

TRUE! it can move up and down

T or F: it is NOT the function of the digestive system to control how much food is ingested

TRUE! that is the function of the nervous system- its hunger and satiety centers combined with the availability of adequate food and other conscious facotrs

Pulmonary Trunk

Takes POORLY oxygenated blood from the RIGHT ventricle to the lungs ** remember that the conus arteriosus in the R ventricle leads to the pulmonary trunk throug the pulmonary valve - divides into R and L pulmonary arteries which enter/exit the hilum of the lung

Where do the neurovascular structures enter and leave the testis (kind of like a hilum)

Testicular Mediastinum - located on the posterior aspect - area is NOT covered by tunica vaginalis layers Arterial supply of testes: - Testicular A. (comes off directly (anterolaterally) from the abd aorta @ apprx. L2) - Artery of ductus (vas) deferens - Cremasteric artery Venous drainage of testes: - Pampiniform plexus (testicular veins) - Veins of ductus (vas) deferens) * the L/R testes have different venous drainage - the pampiniform plexus of vein is some on both L and R BUT - on R: it is lazy and the R. Testicular vein catches a ride with the inferior vena cava - on L: the pampiniform plexus drains into the L testicular vein which then drains directly to the L renal vein * NOTE on the L side the inguinal canal is present --------- * Testis contain 200-300 lobules - lobules are separated from each other by a septum - each lobule contains 2 or 3 coiled seminiferous tubules - seminiferous tubules produce spermatazoa

Spermatic Cord Torsion

Testicular torsion or "twisting of spermatic cord" can occur at any age although most common during adolescence (12-16 yrs old) SURGICAL EMERGENCY!!!!!! - the venous drainage of the testis becomes obstructed and consequently results in arterial ischemia, edema, and hemorrhage * can be tested using the cremasteric reflex - advised to undergo surgery 4-6 hrs after onset of pain to prevent infertility of necrosis of the testis - torsion usually occurs aboud the upper pole of the testis - surgery involves fixing the tetes to the scrotal septum in order to prevent reoccurence Sxs: - sudden, sever onset of pain in scrotum - swelling, redness of scrotum - lower quadrant pain in abd - nause - vomiting (aka emesis) - fever

The ___ is a firm yet mobile (paired) organ suspended within the scrotum (by the spermatic cord)

Testis (testis= singular, testes is plural) - each is anchored inferiorly by the scrotal ligament - these paired ovoid reproductive glands produce: sperm (spermatazoa) and male hormones (testosterone) - apprx. 5cm in length (there is range of normal though) - function optimally BELOW body temperature

Porta Hepatis

The "hilum" of the liver where abdominal structures can enter or leave NOTE: the hepatic veins drain blood away from the liver and when blood is exiting it does NOT pass through the porta hepatis --> instead the hepatic veins drain posteriorly into the inferior vena cava

What is the significance of the delay between atrial excitation and ventricular excitation?

The AP spreads away from the SA node throughout the atria (to the L atrium via. Bachmanns bundle) at a rate of ~1m/s (as cells are electrically coupled via gap junctions) and to the AV node via the internodal pathway - the conduction velocity through the AV node is MUCH SLOWER (0.05m/s) which introduces a DELAY of ~100ms between atrial excitation and ventricular excitation ** this delay is functionally important as it allows the atria to contract before the ventricles are excited- which helps top the ventricles up with blood --- On emerging, from the AV node the AP spreads rapidly down the bundle of His, the L and R bundle branches to the apex of the heart and then up the walls of the ventricles via the Purkinje Fiber Network

Decribe the role of the ENS and PNS in defecation

The Enteric Nervous System (ENS) mediates an intrinsic reflex when fecal material enters the recutm - Afferent signals from the rectum also travel through afferent nerve fibers to the spinal cord ( so brain knowns whats going on but there is a delay) - Extrinsic Parasympathetic motor signals enhance the power of the intrinsic reflex to more forcefully move solid material from the sigmoid colon to the rectum ** start with skeletal nerve fibers- everything is autonomic- nerve fibers that come out of pelvic nerves far away from vagal (it cant do anything here)

The most complex organ in terms of immunological processes

The Gastrointestinal Tract

Hepatopancreatic Sphincter (sphincter of Oddi) vs. Hepatopancreatic Ampulla (ampulla of Vater)

The ampulla is the expanded region (dilated end of a vessel) - then comes the sphincter which is the ring of muscle surrounding and serving to guard or close an opening (in this case the Major duodenal papilla) ** Papilla is defined as a small rounded protuberance on an organ of the body

Transmural Blood pressure (Pi-Po)

The blood pressure measured with a BP cuff Pi= pressure distending or stretching the vessel Po= pressure compressing the vessel Pi-Po pressure diff across a blood vessel wall - influences vessel diameter - increased Pi increases wall tension - at a constant vessel radius (r) the wall tension (T) exactly opposes the transmural wall pressure LaPlaces law: T= (Pi-Po) x r * increased radius= increased wall tension ** The bigger the radius, the bigger the wall tension required to counter any given transmural pressure ** if difference between inside and outside pressures increases, then transmural pressure is increased and vice versa ** Aorta will have the greatest wall tension bc has greatest radius in the arterial network

How is the Foramen Ovale formed and then closed after birth

The endocardial cushion plays an important role in the process It is a central mass of mesoderm that contributes to the formation of: - atrial and ventricular septum - truncal septum - right and left AV valves and canals

What is the clinical relevance that the Mediastinum is a Mobile structure of Loose CT

The fact that it can accomodateschanges in volume and pressure Clinical Relevance= Displacement of Structures & Their Relationships - Mediastinal Narrowing (Silhouetting): can be due to lung masses or pleural effusion that compress the mediastium - Mediastinal Widening: can be due to Tumors, Aneurysms, or Pericardial Effusion (compress the pleura- and occupy more of the thoracic cavity)

Cardiac Ion Channels for Na+

The fast voltage gated Na+ channel (similar to that found in muscle and neural tissue) - open at negative voltages (ex. -70mV) and are VOLTAGE GATED - activates rapigly (opening of m gate) and then inactivated rapidly (slower closure of h gates) which closes the channel despite the activation gate still being open * m (activation) and h (inactivation) gates: BOTH gates must be open to allow Na+ entry into the cell normal resting potential: m is closed, h is open ** depolarization opens the m gate rapidly: Na+ ions enter cell down gradient ** this initiates the closure of the h gate- but this closes more slowly than the activation gate opens so THERE IS A BRIEF PT (1-2ms) during the upstroke (phase 0) of AP when both the activation and inactivation gates are open.. - Na+ enters the cell DOWN its concentration gradient- this generates an inward membrane current ** This DEPOLARIZED the cell (i.e. makes the cell interior more positive) ** Large inwardly directed electro-chemical gradient for Na ions and so when channels open, ions will enter the cell. This takes postive charge into the cell which will make the interior less negative, i.e. more positive which is called depolarizing the cell ------- Repolarization phase (3) - h gate closed, activation gate still open: Na+ CANNOT move through channel despite the open activation gate Cant be reactivated till resting membrane potential achieved (phase 4 in atrial and ventricular tissue)- so channels are in refractory state * Once repolarization complete, and resting membrane potential reestablished- the activation gate closes and inactivation gate opens and channel can then be re-activated and generation of new action potential is now possible

Portacaval Anastomoses *** important***

The hepatic portal vein and its tributaries have NO valves, therefore if the venous drainage of the GI gets blocked at the hepatic portal vein, then the blood can bypass the liver by flowing in a REVERSE DIRECTION and drain to the IVC through an alternative route 4 alternative routes: - Gastroesophageal: L. gastric vein --> Esophageal vein (Azygous system) - Paraumbilical: Paraumbilical vein--> Epigastric vein (superior, inferior, and superficial) - Retroperitoneal: Colic (& Splenic) vv. --> Retroperitoneal VV. - Anorectal: Superior Rectal vv. --> Middle/Inferior rectal vv. **** These portacaval anastomotic connections become clinicaaly important when the direct drainage route to the liver is blocked

Tunica Intima

The innermost layer of a blood vessel (artery or vein) * the only layer found in capillaries Composed of: 1. Endothelium - single layer of squamous endothelial cells Endothelial cells are - flat and elongated with long axis PARALLEL to the direction of blood flow - cells are joined by TIGHT JUNCTIONS * A smooth surface is established for blood flow and prevention of blood clotting 2. Basal lamina - supports the endothelium 3. Subendothelial layer - Loose CT consisting of collagen and occasional smooth muscle cells (SMCs) ** this layer allows the tunica intima to move INDEPENDENTLY from other layers

Describe the synthesis of bile acids

The liver converts cholesterol to primary bile acids (cholic acid and chenodeoxycholic acid)- in a series of 14 rxs occurring in 4 different cellular organelles - bacteria in the terminal ileum and colon may dehydroxylate bile acids, yielding the secondary bile acids deoxycholic acid and lithocholic acid - The hepatocytes conjugate most of the primary bile acids to small molecules such as glycine and taurine before secreting them into the bile - In addition, those secondary bile acids that return to the liver via the enterohepatic circulation may also be conjugated to glycine or taurine

Is the liver intra or retorperitoneal?

The liver is an intraperitoneal organ that is located in the Right Upper Quadrant (RUQ) *** it is a MAJOR lymph roducing organ (25-30% of lymph) It is the LARGEST gland in the body with many vital functions (weighs ~3.3lbs or 1.5kg)

Acute Appendicitis

The most common condition associated with emergency surgery Cases are usually obstructive in origin and nature - causes of obstruction of the appendiceal lumen include lymphoid hyperplasia from IBD or infection; fecal stasis of fecalith - the initial pain is mild and ill-defined crampy pain and referred to the periumbilical area and is due to distension of the appendiceal lumen - the patient gradually develops visceral peritonitis and then parietal peritonitis follows; the periumbilical pain then shifts to the right lower abd in 2/3rd of cases * NOTE: Fecalith= a stone like mass of layered calcium salts and fecal debris that can cause infection

The apical membranes of gastric epithelial cells are no more and no less resistant to damage from concentrated acid than would be any other cell membrane. Their pH needs to be close to 7 to prevent denaturing of membrane proteins, etc. This is possible because of the

The mucus they secrete which protects their membranes from damage (The mucosal barrier). When food is eaten, rates of secretion of both highly viscous mucus and HCO3- increase with acid secretion: - Bicarbonate crosses from blood to the mucous gel by crossing two membranes - Mucus is stored in large granules in the apical cytoplasm of mucous neck cells and surface epithelial cells and is released by exocytosis * Bicarbonate buffers the gooey fluid right next to cell surface (pH 7.0) protecting the proteins there from pepsin digestion. In turn the viscocity of the fluid there is thick enough to prevent highly acidic fluid from the gastric lumen from easily making contact with otherwise-damageable apical membrane proteins ----------- Both bicarbonate & proteins from gel at cell surface gradullay move by bulk flow and diffusion away from the cell surfaces - further out the bicarbonate is used up and the glycoproteins are gradually digested by pepsin in the "mucous gel neutralization zone" - bc left unopposed this would eventually let concentrated stomach acid damage epithelial cells, both bicarb and mucus must be continually replaced at the apical surface * while this is true of every mucous membrane, nowhere else is this continual replacement more important than in the stomach

Vasa Vasorum "Vessels of the Vessel"

The tunica are TOO THICK for blood to diffuse from the lumen (tunic intima region) across the layers, therefore large blood vessels ahve their own blood supply (this is called vasa vasorum) Vasa vasorum are located in the - Tunica Adventitia - Outer Tunica Media Vasa vasorum consists of: - arterioles - capillaries - venules

Major Salivary Glands

There are 3 MAJOR salivary glands: Parotid, Submandibular and Sublingual - secrete into the oral cavity through one or few large excretory ducts - surrounded by a capsule of dense irregular collagenous CT, that invades the substance of the gland to form septa which subdivide each gland into lobes and lobules ** these are ALL paired glands

The anatomical constrictions of esophagus are of considerable clinical importance bc of the following reasons:

These are sites where - swallowed foreign bodies may get stuck in the esophagus - structures develop after ingestion of caustic substances - predilection (preference) for carcinomas of the esophagus - it might be difficult to pass esophagoscope/gastric tube

Describe segmentation movements in the Small Intestine

These fx to "chop" liquid chyme into separate compartments called segments - as constricted regions relax and relaxed regions constrict (circular muscle contractions), material within move back and forth - each movement only lasts for a few seconds at a time - this helps mixinig (churning) in the small intestine - Depending on circumstances, the segments can be regularly spaced, irregularly spaces, or isolated ** in the fed intestine, these stretch-driven segmentation contractions are very short and are superimposed by persitaltic waves - over time the peristalsis moves the intestinal contents towards the anus * these movement allow mixing and movement of materials for proper processing of nutrients and waste through the intestinal tract

Describe Zymogen Processing

They are produced with an amino terminal sequence that prevents enzyme functions Called "-ogen" or "pro-" - chymotrypsingoen - tryosinogen - pepsinogen - proelastase - proenteropeptidase - procarboxypeptidase A or procarboxypeptidase B ** all these above are produced by the pancreas EXCEPT pepsinogen which is made in stomach and pepsinogen is only one with autoactivation- at a pH below 5 it can auto-cleave its "N-terminus" And these are cleaved by specific proteses: - Trypsinogen is cleaved by enterokinase on enterocyte membranes - Trypsin is required to cleave chymotrypsinogen, proelastase, carboxypeptidases (Trypsin is produced by the last meal to work in the current meal- after a meal enterokinase is activated which activates trypsin that activates cascade for that meal- any enterokinase/enteropeptidase produced since last meal wil be activated by trypsin again)

Describe the Ducts of the Salivary Glands

They contain: - epithelial cells - membrane proteins (ion secretion and absorption) - tighter junctions between cells- no fluids passing through unlike the acini

Describe the Acini of the Salivary Gland

They contain: - myoepthelial cells (have squeezing capacity) - secretory granules (exocytosis) - membrane proteins (ion secretion) - "leaky" junctions between cells

Glycero-phospholipids (aka Phosphoglycerides)

They have - a glycerol backbone - 2 FAs: middle possition (2-position) FA is typically unsaturated, end (1) position FA may be saturated - phosphate at other end of the glycerol - can have a head group attached to the phosphate Headgroups: - choline - ethanolamine - serine - inositol * in addition to constituting major structural component of membranes, many lipids participate in specific cell signaling events

Vit B1, Thiamine typically occurs as

Thiamine Pyrophosphate Serves as a cofactor in several metabolic enzymes carrying out aldehyde transfer (carrier for the intermediate) or oxidate decarboxylation, notably: - pyruvate dehydrogenase - alpha-ketoglutarate dehydrogenase - transketolase (HMP- hexose monophosphate shunt) *** Transketolase is measured in isolated RBC to check for thiamine deficiency (assayed by erythrocyte transketolase reaction)

Palpation and the Clinical finding of guarding

This is the voluntary contraction of abd musculature - increased abd wall muscle tone can result from failure to relax, a cold room or examining hands, and anxiety or fear of increased pain; interferes with effective deep palpation ** Distinguished from INVOLUNTARY rigidity by being abolished suitable maneuvers, such as distracting the patient ** Guarding is usually symmetrical, nontender and bilateral

55yr/o man with h/o systemic HTN and hypercholesterolemia complains of chrushing chest pain radiating to his jaw and arm. He has an elevated troponin I level you suspect

Thrombis overlying a ruptured artherosclerotic plaque resulting in occlusion of the vessel

Iodine is used for

Thyroid hormone - Iodine can be found in iodized salt (0.00*% KI) - There used to be wide-spread deficiency but no more bc of the salt (deficiency can cause Goiter) RDA ~ 0.15mg/day

In the respiratory tract what is the most important structure in the epithelial cells that keep microbes out

Tight junctions serve the most important function! they do not let anything through ** epithelial cells of respiratory tract are at the interface between the environment and the sterile compartments of the body- they provide an important physical defense barrier functions with their **tight junctions but also desmosomes and adherence junctions ------- * epithelial cells also have secretions for chemical defense (Beta-defensins, cathelicidins, surfactant proteins A and D, and lysozyme)

Chest tube/Chest Drain

To REMOVE EXCESS fluid, blood, pus or air - IDEAL SITE: 5th-6th intercostal space (at nipple line) along the midaxillary line (below this level can potentially damage the diaphragm) ** Fluid removal: tube directed INFERIORLY towards the costodiaphragmatic recess ** Air removal: tube directed SUPERIORLY towards the cervical pleura

In GI what is the cellular response to intestinal microorganisms

Tolerance Induction! - generation of Treg cells which make IL-10 and TGF-beta (anti-inflammatory cytokines) which are important in induction of tolerance * Can you remember what the surface markers of Treg cells are? ------ Steps of Induction of Tolerance to Endogenous Bacteria include: 1. Recruitment and activation of Treg cells 2. Increased production of anti-inflammatory cytokines (IL-10, TGF-beta) Loss of regulation--> inflammatory bowel disease (ex. Crohns ) 3. Enterocytes have decreased expression of co-stimulatory molecules (B7: CD80/CD86) 4. Increased TOLLIP expression which down-regulates TLR/NLR expreassion 5. Decreased CD14 expression on intestinal macrophages *** TLR4 tends to be active with CD14 (TLR4 binds to LPS or endotocin or gam (-) organisms) *** decreased CD14 means decreased TLR activity

Umbilicus is often used as a key landmark of the

Transumbilical region ( horizontal line through umbilicus- divides into upper and lower quadrants) at level of - dermatome T10 - vertebral level L3/L4

The third part of the large intestine which is the longest, most mobile section

Transverse Colon - intraperitoneal (mobile) - connected to the post. abd wall by the transverse mesocolon ( a modification of the dorsal mesentery) which allows it to hang down to the level of the umbilicus (apprx. L3/L4) - attaches to the diaphragm at the L colic (splenic) flexure via the phrenicocolic ligament * remember that the greater omentum attaches to the greater curavature of the stomach and the transverse colon

In the abd cavity, the ______ can be used to delinate the boundary between supracolic and infracolic abd compartments

Transverse Mesocolon (*remember this is a portion of dorsal mesentery) --- Supracolic viscera: - distal esophagus - stomach - duodenum: 1st and part of 2nd*** - pancreas - spleen - liver - gallbladder Infracolic viscera: - Small intestine: Duodenum 2nd, 3rd, 4th, jejunum, ileum - cecum - appendix - large colon - rectum - anus

Pericardial Sinuses "Passageways"

Transverse Pericardial Sinus: - a passage behind the ascending aorta and pulmonary trunk - formed via degeneration of the dorsal mesocardium **** A ligature is passed through the transverse sinus to clamp the ascending aorta and pulmonary trunk during cardiac surgery Oblique Sinus: Located POSTERIOR to the heart - reflection of pericardium surrounding the pulmonay veins, IVC and pericardium overlying the esophagus

Dietary Fat or Triglycerides includes

Triglycerides are the stoarge form and is waht we refer to as fat * FAs attached to glycerol backbone through ester linkages - Saturated (palmitate) FAs: NO DB- pack well in lipid bilayres and reduce fluidity - Mono-unsaturated FAs: have a single cis-DB- introduces a kink and keeps membrane more fluid - Trans FAs: produced mostly from chemical hydrogenation of poly-unsat. oil to alter their phys. properties, also produced by prolonged heating of unsaturated or polunsaturated oils (*remember in nature mostly cis DB are made) - these trans have more deliterious health affects - Poly-unsaturated Fats: two or more DBs - Essential FAs: Linoleic (arachidonic acid precursor, an important signaling molecule) and Linolenic (other omega 3 FA like DHA- Docosahexaenoic acid and EPA- Eicosapentaenoic acid are important for maintaining membrane fluidity) - they are omega-6 and omega-3 fatty acids respectively

T or F: Dietary cholesterol has little impact on plasma serum cholesterol level

True! - this realization is relatively recent, major change - in past there was severe limitation on dietary cholesterol to 300mg- for eggs (186mg), this was coupled with past mistaken higher measured values, leading to recommendations limiting egg consumption * currently the 2015-2020 dietary recommendation DONT set an upper limit on daily cholesterol - this has been replace with recommendations to limit saturated, and trans fats, and with minimum consumption levels of unsaturated, polyunsaturated, and essentail fats as better means for lowering serum cholesterol through diet ** STATINS= extermely effects drug in lowering serum cholesterol and can often lower it more than diet and exercise alone

T or F: Choline can be synthesized by the body

True! Choline can be synthesized by the body, so it is not strictly required- but an adequate dietary intake is necessary for good health * VitB4- one of several compounds, including choline that is no longer considered a vitamin - choline is a pseudovitamin bc it can be synthesized in the body

T or F: The GI tracts contents are OUTSIDE the body

True! Thats what mucous membranes are all about, provide border between outside the body and inside where the blood and extracellular fluid are - if bacterior live in the colon thats okay bc theyre functionally the same as bacteria in the skin - only becomes problem when somethin is compormised and the bacteria get in the blood in significant numbers- can lead to sepsis ***** ANY fluid contained n the lumen of the GI tract is considered to be "outside the body" for purposes of body fluid compartments ex: exocrine pancreas and lacrimal (tear) glands both remove fluid from the body - the big difference is that in the GI tract, we get most of it back

T or F: lower serum cholesterol correlated with lower death rate from coronary artery disease

True!! - serum cholesterol is carried mostly in low density lipoprotein (LDL) and a smaller amount in high-density lipoprotein - increased LDL correlates with higher incidence of coronary artery disease - relatively higher HDL may be beneficial * We have seen that there is a correlation between serum cholesterol (mostly LDL) and death by CVD) - there is also a correlation between saturated fat intake and LDL cholesterol levels - yet, a number of studies have failed to show a clear link between consumption of saturated fat and increased incidence of CVD

Bristol Stool Scale

Type 1 (longest transit through gut): Seperate hard lumps, like nuts, hard to pass (constipation- if you have diverticuli like in old ppl and one of these gets stuck in gut wall can lead to sepsis) Type 2: sausage shaped and lumpy Type 3: Like sausage but with cracks on its surface Type 4: like sausage or snake, smooth and soft Type 5: Soft blobs with clear-cut edges (passed easily) Type 6: fluffy pieces with ragged edges, a mushy still Type 7: watery, no solid pieces (entirely liquied) this one have the shortest transit ~10hrs **** THE LONGER WASTE REMAINS IN THE COLON AND RECTUM, THE FIRMER IT GETS -- - Human stools may very in consistency from liquid (associated with diarrhea) to very small, very hard lumps (associated with constipation and/or diverticulitic associated with diverticulosis). The water content of feces determines its consistency and this in turn is dependend on solute absorption and the speed that the gut contents is moving through the GI (about 25% of the usual content of feces is made up of intestinal bacteria) ---- Bristol stool scale can be used in assessment of transit time and is regarded as a good descriptor of stool form and consistency which is a musch better predictor of whole gut transit than of defecation freq or stool volume. It is also much more definitive than "semi-solid" which would usually correspond to 4-5 vs. 3 lelevsl of "solid", from solive but soft (3) to hard solid pellets --- Cecum: 7 (fluid) Ascending Colon: 7-6 (semi-fluid) Transverse Colon: 7-5 (mush) L colic flexure: 6-5 (semi-mush) Descending colon: 5-3 (semi-solid) Rectum: 3-1 (solid)

Mesenchymal Tumors

Uncommonly can develop in the GI - arising from dysplastic changes of the mucosa (epithelial cells evolving into Anaplasia) - in stomach tends to form globular masses - fleshy tissue "grey-white" - do not usually ulcerate but do stretch mucosa which can lead to ulceration --> bleeding ***** Gastrointestinal Stromal Tumors (GISTs) are the MOST COMMON type

In initial appendicitis- when the appendix becomes inflamed, it swells and stretches its covering of the

VISCERAL peritoneum - general visceral afferent (GVA) axons enter the spinal cord at the T10 vertebral level - causes vague pain referred to the peri-umbilical region

What are VLDL, LDL, HDL

VLDL: Very low density lipoprotein- carries triglycerides and cholesterol from liver to periphery LDL: low density lipoprotein- delivers cholesterol from liver to periphery- derived from VLDL HDL: high density lipoprotein. Scavenges cholesterol from the periphery and sends it back to the liver ---- Ingesting: - Trans fatty acid: increases LDL, decreases HDL-> increasing incidence of coronary heart disease - Saturated FA: increases LDL, little effect on HDL--: increased incidence of coronary heart disease, may increase risk of prostate and colon cancer ---- where as the following decrease the incidence of coronary heart disease: - Monounsaturated FA: decreases LDL and HDL - Polyunsaturated FA (omega-6): decrease LDL and HDL- provise arachiodonic acid which is important precursor of prostaglandins and leukotrients - Polyunsaturate FA (omega-3): little effect on both LDL and HDL (suppress cardiac arrhythmias, reduce serum TAG, decrease tendency for thrombosis, lower BP)- in addition to decreasing incidence of coronary heart disease, also decreases risk of sudden cardiac death

Low Density Lipoprotein, LDL is produced in the circulation as the end product of

VLDLs Compared to VLDLS, LDL: - contains only Apo B-100 - smaller size and more dense (increased percentage of protein) - less TAG - more cholesterol and cholesterol esters * LDLs transport cholesterol from liver to peripheral tissues Uptake of LDL at tissue level is by: - LDL receptor-mediated endocytosis in target tissues and liver - Recognized by ApoB-100 - Occurs in both peripheral tissues and liver; 70% of cholesterol is returned to the liver through LDL receptors

Colonic Motility involved slow waves. Since Midgut-Hindgut border is within the colon what two types of PNS fibers innervate the colon?

Vagal and Sacral PNS fibers (Vagal --> Sacral at about midgut/hindgut when getting out of transverse colon into descending colon) - SNS fibers modulate colonic motility via mesenteric and hypogastric plexuses In general, sympathetic stimulation INHIBITS colonic motility and all other motility in the gut - Parasympathetic, by either route- promote it using ACh as a neurotransmitter * Longer, more intense but less frequent (3-7/min) slow waves result in contractions (this is not like the 10-12/min that we saw in duodenum- but it is still not as slow as what can be seen in the stomach) -------- The slow waves in the colon look very diff. from those of stomach or SI bc the material to be moved might be solid and req. very powerful contractions in order to overcome resistance to flow through this tube- BUT they work in the same way as other slow waves, at a relative slow pace

Describe the control of pancreatic duct cell secretion (the processing of the primary secretion)

Vagal neurons: - ACh (+ Phospholipase C, PLC) Endocrine/Paracrine Agents: - SECRETIN (basolateral, +adenylyl cyclase) is the most important - there may be others (ex. CCK binding with less affinity) - there may also be some apical receptors (ex. for ATP) but they too are less important than secretin *** ALL these increase CFTR activity !

R/L Recurrent Laryngeal nerves are branches of the

Vagus Nerve, move cranially with larynx - LEFT recurrent laryngeal nerve loops under left 6th arch artery derivative (ductus arteriosus) - RIGHT recurrent laygeneal nerve loops under the 4th arch artery derivative (right subclavian artery)

Chronic constipation can lead to hemorrhoids bc of frquent

Valsalva maneuvers - this can also occur in weight lifters and is why exhaling during a lift is proper lifting from ** In heart failure patients, a valsalva maneuver can be FATAL - in a person with a compromised heart, elevated cardiac work and oxygen demand (especially during phase I and IV- higher afterload) can lead to ischemia and a heart attack - heart patients must take measures to prevent constipation

Measurement Variation

Variation is inherent aspect of measurement and data Causes: - living things are "non-standardized" - human factors - environment - data collection and recording - margin of error IF you dont understand the variation that lives in your data you will be tempted to: - deny the data - see trends where there are no trends - try to explain natural variation as special events - blame or credit to people for things over which they have no control - distort the process that produced the data

Capacitance Vessels (Veins)

Veins act as a "reservoir" for blood bc of their high compliance (10-25 times more compliant than arteries) - this increase reservoir is used to increase venous return and cardiac output How? increase symp activitiy to venous smooth muscle cells --> smooth muscle cell contracts and increased venous tone --> increased tone causes a decrease in venous compliance --> venous blood reservoir is displaced towards the heart --> increased venous return and cardiac output *** compliance decreases at higher pressures and volumes (i.e. vessels become "stiffer" at higher pressures and volumes) ** at lower pressures the compliance of vein is about 10-25x greater than an artery- therefore veins can accomdate a large change in blood volume with onle a small change in pressure, which is why they functions as a blood reservoir called capacitance vessels ** this venous reservois of blood is important in circumstance where its necessary increase CO, such as during exercise or hemorrhage ** blood in the venous reservoir is made available by an increase in symp. nerve stimulation of the smooth muscle of veins - the contraction of smooth muscle cells causes venous dynamic compliance to decrease and reduces the volume of blood held in the veins- this displaces blood toward the heart and increases CO

Relationship between Venous Return and Right atrial pressure

Venous return (VR) is dependent on the driving pressure between the venous system and the RA ** described by vascular function curve ** blood flwing through the veins back toward the heart is called venous return (or cardiac input) On avg CVP ~10mmHg and RAP ~2mmHg- giving pressure gradiant of 8mmHg - so only 8mmHg pressure diff is needed to drive blood through venous system back to heart ** since venous return (cardiac input) = CO--> it only takes a pressure gradient of 8mmHg to create a flow of 5L/min (normal CO) through the veins

Mesentery

Ventral Mesentery (small) and Dorsal Mesentery (larger)- both modified further in development - mesenteries (and ligaments) provide pathways for vessels, nerve, and lymphatics to pass between abd organs - they help to provide a continuous connection between the viscerl and parietal peritoneum - contain fat (adipose tissue) as well as the arteries, veins, lymphatic vessels, and nerves that supply the abd organs - also functions to connect organs to the posterior abd wall **** as we have rotation of the gut tube the primitive dorsal and ventral mesenteries are mdoified

How can hernias be treated?

Via many diff. surgical techniques that act to repair and reconstruct the posterior aspect of the anterior abd. wall and this procedure is known as hernioplasty or herniorrhaphy * hernioplasty: replace mesh- tension FREE * herniorrhaphy: suture back- A LOT of tension

A causative agent for secretory diarrhea

Vibrio Cholerae Diarrhea can reach levels as high as 1 L/hr - leading to life threatening: - hypovolemic shock- loss of water - hypokalemia- loss of potassium - non respiratory acidosis- loss of bicarbonate

Fluid movement across the gut is a balance. What two structures aid in this?

Villus epithelium- ABSORBS Solute and H2O Crypt epithelium- SECRETES Solute and H2O * these processes are regulated independently - since there are regulated independently, the balance of which one has greater flux determines the net movement of fluid into the lumen (secretory) of into the blood (absorptive) Net movement is a balance: Jnet= Jabs-Jsec * movement can occur through trans or paracellular routes ------ To a large extent, fluid secretion is driven by secretion of Cl- and HCO3- ions (or chloride and hydrogen in the gastric pits) - sodium follows chloride and bicarbonate, and water follows ----- Remember if there is any condition in which too much water is secreted from crypts (ex. cholera), if absorption (from villus) can be increased as well then the balance can be maintained as the cause is identified and treated.

Site of absorption in duodenum and jejunum

Villus! - intestinal cells "stick out" into the intestinal lumen, increasing surface area - cells change function as they ascend villus: from secretory --> absorptive - absorptive cells have micorvilli, folds that increase apical membrane area still more - deep to these cells are arterioles, venules, and both blood capillaries and lymphatic capillaries (lacteals) ------- These villi & microvilli allow a much larger number of membrane-associated enzymes and transport proteins than would otherwise fit along the length of the tube * the microvilli are collectively called the "brush border": they are responsible for a great deal of the diff. in surface area over that of the tube proper --------- In Celiac Disease, there is a change in structure of the inner lining of the tube such that the villi and the brush border with it is significantly reduced in size--> leading to malnutrition as absorption of nutrients becomes less optimal in proportion to the loss of surface area

Fat soluble vitamins include

Vit DEKA (D, E, K, A) - Vit D (cholecalciferol) - Vit E (tocopherols) - Vit K (phylloquinones, menaquinones) - VitA (retinol, Beta-carotenes) * these all have upper limits, except for Vit K * fat soluble vitamins distribute in fatty tissues so they are easier to accumulate in excess (stored in adipose tissue and liver) - can be transported with fat (chylomicrons) - can be toxic because they are NOT readily excreted

Cobalt is only used in the body as a

Vitamin B12 constituent - It is found in Meats and Dairy - Its deficiency can be seen in Pernicious Anemia

___ is used to prevent isoniazid-induced B6 deficiency and neuropathy in people with a risk factor, such as pregnancy, lactation, HIV infection, alcoholism, diabetes, kidney failure, or malnutrion

Vitamin B6

Menkes Disease

X-linked recessive condition due to mutation in ATP7A gene, which encodes intestinal Cu+2-Translocase - Copper accumulates in small intestine and kidneys, with LOW levels in the brain * This is a RARE disorder characterized by kinky hair, seizures and unstable body temperature - Ceruloplasmin and Copper will be very low in the blood and other tissues, but built up in intestines and kidneys TREATMENT: Copper supplementation, with poor prognosis and usual mortality in the first 3 yrs of life

Molybdenum is a cofactor in more than 50 enzymes (mostly bacterial enzymes) The important human ones are

Xanthine Oxidase, Aldehyde Oxidase, and Sulfite Oxidase (also needed for Nitrogenases and the oxidizin proteins that have been listed) - Deficiency is RARE but results in high blood urate and sulfit- it is associated with increased rates of esophageal cancer RDA is ~45microgram/d It can be found in: Legumes, Grains, and nuts

In development, blood vessels begin to form NOT ONLY in the embryon but in the

YOLK SAC - the initial connections between the placenta and embryo is established by week 4

Is it okay if harder-to-digest materials have to stay in stomach longer?

Yes, because we can control gastric motility separately from either oral or intestinal motility

5-methyl-THF trap hypothesis

a B12 deficiency fails to regenerate THF from 5-methyl-THF - 5-methyl-THF accumulates and creates a folate insufficiency * Thus signs and symptoms of B12 and folate deficiency are similar-- both result in a macrocytic anemia Sxs of macrocytic anemia: need to be investigated to determine whether the deficiency is folate or B12

Vitamin B12, Cobalamin has a

a Cobalt containing, pyrrole ring system (similar to porphyrins, but not identical) - comes in various forms (-CN, -CH3 (methylcobalamin), -deoxy-adenosyl (5'-deoxyadenosylcobalamin)- the later which are the only ones that are important in rxs.) Req. for only two known specific reactions: - methylmalonyl-CoA mutase (MCM): resides in the mitochondria and catalyzes the isomerization of methylmalonyl-coA to succinyl-CoA- it is involved in metabolism of branched-chain AA isoleucine and valine, as well as methionine, threonine, thymine and odd-chain fatty acids - methionine synthase

Conversion of Symbiosis to Dysbiosis can be due to

a changed ratio of organisms, overgrowth of a species to the level to become pathogenic - most pathogenic species are already present but kept in check by the competition with other organisms - large scale destruction of the microorganisms through antibiotics, anti-flagellate and other medications alter the abundance of the competitive and beneficial organisms ** changes in microbial by-products alter the health and growth of the enterocytes --- Symbiosis takes into account life style and diet (the metabolome is healthy) - if metabolome altered (for example with long-term antibiotics) this can lead to --> Dysbiosis (a diseased Metabolome) can lead to - Digestive dieases (chrons disease, celiac disease) - Colon cancer - Obesity, diabetes - Neurological disease etc...

Peptic Ulcer Disease

a chronic illness manifested by recurrent ulcerations in the stomach and proximal duodenum - acid and pepsin are thought to be crucial to ulcer development, but the great majority of peptic ulcers are directly commonly related to infection with Helicobacter pylori or NSAID use - rarely due to gastrinoma - gastritis is acute or chonic inflammation of the gastric mucosa and has various etiologies

Heart Failure (HF)

a clinical syndrome associated with reduced cardiac ability - to eject blood (forward failure, systolic dysfunciton) OR - to be filled with blood (backward failure, diastolic syndrome) ** syndrom: a group of sxs, sings, and structural and fx abnormalities that have common pathogenic mechanisms

Orlistat is

a competitive inhibitor of most lipases - older name= trihydrolipstatin - 83% is expelled in feces within 24hrs, with the remainder expelled via fecal or urinary pathways within 5 days - like Olestra the primary side effect is decreased uptake of lipid soluble vitamins - Some counterfeit versions sold via internet do not have orlistat but have the now banned Sibutramine (Meridia) which has significant side effect of increased cardiovascular events and stroke

Atherosclerosis

a form of arteriosclerosis (hardening of arteries) characterized by deposition of plaques containing cholesterol and lipids on the innermost layer of large and medium sized arteries Vessels involved: - aorta and its major branches (renal, mesenteric) - coronary aa - cerebral aa - femoral and popliteal aa ------ in vessel macrophages will be transformed into foam cells and have fibrous cap and contain lipids, calicum and cellular debris

During exercise, high-pressure baroreceptors are reset such that

a higher mAP is required to achieve the same firing rate - higher than normal MAP can be maintained during the period of exercise - this "resetting" is reversible unlike with chronic hypertensions

H. Pylori

a microbe associated with peptic ulcers Causes increased acid secretion because of: - increased parietal cell mass and increased gastrin secretion - decreased inhibition of acid secretion (H. pylori- induced gastritis reduces somatostatin production in the antrum with loss of the negative feedback on gastrin secretion - in duodenum- bicarbonate secretion is decreased by H. pylori inflammation and the damage an repair leads to gastric metaplasia which H. pylori colonizes, causing local release of cytokines and further damage *** one important metabolic fx. of H. pylori= activity of the urease enzyme- which produces ammonia (may be important in pathogenesis of ulcer disease, since it may degrade barrier function - the activity of the enzyme allows diagnosis by examining urea metabolism of the bacteria in a breath test [ pt. is fed a meal containing 13C- labeled urea- H. pylori urease activity metabolizes the labeled urea- incorporating the 13C into CO2 which can be detected in exhaled air - Other diagnostics for H. pylori include- production of antibodies in blood, presence of antigen in the stools and other methods including histology, microbiology and biochem of antral biopsy material

If a pt has HTN and also has Afib

a non-DHP drug such as Diltiazem or Verapamil may be better choice bc they mainly function in - depression of automaticity at SA node - depressin of conduction at AV node

Peristaltic Rush

a rapis intense peristalsis, occurs with some infections or other irritants (like certain foods) - it sweeps the small intestine clear of most contents in minutes- at the price of diarrhea * all digestive secretions have no time to be absorbed before they are flushed into the colon along with the ingested stimulant material (Ex. hot sauce)

Standing leads to

a reduction in venous return (preload), reduction in SV, reduction in CO and MAP; baroreceptors return MAP towards normal

The pancreas is both an exocrine and endocrine gland. Its exocrine secretions flow through

a series of ducts into the duodenum, mixing with bile and then with chyme Its exocrine secretions contain: - bicarbonate - water - digestive enzymes (still inactive, go into lumen of small intestine where they can activate and do their job) It is stimulated to secrete by a number of hormones and the autonomic nervous system ** For the purposes of exocrine secretions, it is helpful to think of pancreas and the salivary glands as "siblings"- they are NOT identical twins by any means but they share more similarities than differences (like salivary glands but have much more permeability in ducts than salivary glands) *** a third member of this family of related exocrine glands is the lacrimal gland that secretes tears

Cardiolipin

a specialized lipid found principally in the mitochondrial inner membrane Role: make membrane more impermeable to ion by making very tight inner mitochondrial membrane * structure as 4 FA tails

the esophagus has what type of epithelium

a stratified squamous * note that the esophagus leads to the cardiac region of the stomach (the stomach is simple columnar epithelium with gastric glands) *then the pyrlorus of the stomach leads to the duodenum via the duodenal cap/fold DONT forget about the gastroduodenal junction!

Vasectomy

a surgical procedure performed on males to produce infertility and act as a contraceptive measure - spermatozoa may still be present in first few post-operative ejaculations - after procedure, ejaculatory fluid will only contain secretions from the seminal vesicles and the prostate Procedure: * has to occur bilaterally * performed under local anesthesia * small incision is made in the upper region of the scrotal wall and the two ductus (vas) deferens are ligated

Constipation

a symptom/sign, NOT a disease - req specific criteria for a diagnosis - excess absorption of water and/or inadequate motility of the colon leads to stools that are excessively dry and often difficult to pass - can be associated with other conditions such as congenital megacolon or colonic diverticulitis

Visceral layer of the peritoneum covers and invests

abd. organs the protrude into the peritoneal cavity - psin is GENERALIZED (is referred)

____ are useful in initial evaluation of urinary stones

abdominal radiographs

Autoregulation

ability of an organ to maintain a constant blood flow when arterial pressure changes - occurss predominately in vessels within the heart, brain and kidney *** myogenic theoary causes vasoconstriction and reduced flow- explains the reflexive vasoconstriction --> reduces blood flow to organ -------- If there was a sudden decline in perfusion pressure- vasodilation and increased flow would result from metabolic theory due to low PO2

Main signal for secretion of Secretin

acid (pH < 4.5) in duodenal lumen - minor singal: acid in jejunal lumen Secretin is produced by: S cells, mostly in the duodenum (some in jejunum) these have sensors that detect the low pH Main pathway for action: Endocrine (secreted into blood for delivery to target tissues) Main target tissues: pancratic ducts (secrete bicarbonate & H2O to neutralize stomach acid), bile ducts, pancreatic acinar cells. Minor target: vagal afferent fibers Main actions: increase secretion of bicarbonate-rich pancreatic juice and bile into duodenum *** need to neutralize acid bc enzymes in the lumen have a pH close to 8- they would be completely inactive at a pH of 4.5

With non-DHP CCBs

action potential conduction slows greatly through AV node due to small size of cells AND slowing of rise of AP --> suppors more effective ventricular filling

Cells of the SA node set the frequency of

action potential generation - bc they LACK a stable membrane potential between successive action potentials and instead the membrane potential displays a progressive slow depolarization, called the Pacemaker Potential during Phase 4 ** the cells of the SA node initiate the AP at a rate of ~60-100x/minute and as this cell generates APs at a faster rate than other pacemaker cells present in the heart (ex. AV node) then the SA node is considred to be the PRIMARY PACEMAKER OF THE HEART ** this is caused by a more rapid rate of phase 4 depolratization than in any other cardiac cell type

It is common that DIRECTLY after a vulnerable coronary plaque, that a

acute myocardial ischemia will follow

Pain during Acute Pancreatitis is due to

acute peritoneal inflammation caused by activated pancreatic enzymes - elevation in amylase/lipase >/= 3 times normal is highly accurate for the diagnosis of acute pancreatitis The diagnosis of acute pancreatitis requires at least two of the following: - typical epigastric abd pain (piercing through the back) - amylase/lipase evaluation >/= 3 times upper limit of normal - confirmatory findings on cross-sectional imaging like CT, MRI ** You can have an acute interstitial pancreatitis or an acute hermorrhagic pancreatitis

Caloric needs increase with

age and activity until about 20, and then decrease with further age - generally women have somewhat lower caloric requirements - energy requirement peaks at late teens (19-20), decline slowly with age

orthostasis

aka orthostatic hypertension - is a type of low blood pressure that happens from standing up from sitting or laying down

The pharynx contributes to the

alimentary (food) and airway canals - extends from base of skull- C6 - continuous superiorly with oral and nasal cavities and inferior with trachea and esophagus - subdivided into nasopharynx, oropharynx, and laryngopharynx * pathway that food gets from oral cavity to esophagus * NOTE the epiglottis is a cartilaginous flap that covers the laryngeal inlet upon swallowing in order to prevent food from entering the larynx - food doesnt go back up into nasopharynx because it is cut off by the soft palate

Capillary hydrostatic pressure (Pc) declines

along the length of the capillary due to resistance * at arteriolar end: capillary hydrostatic pressure greater than plasma colloid osmotic pressure, so fluid moves across the wall out of the capillary (filttration) ** at venous end of capillary- hydrostatic pressure is less than plasma collid osmotic pressure- so fluid moves from the interstitial space back into the capillary (reabsorption) **** by adjusting capillary hydrostatic pressure via cahnges in arteriolar resistance, the amt of fluid moving across the capillary wall can be varied Ex. hemorrhage causes a decrease in BV which reduces mean arterial pressure (MAP) thus decreasing capillary hydrosttic pressure- this reduces the net driving pressure and therefore less filtration occurs

Calcium channel blockers bind at the

alpha subunit of L-type Ca2+ channel leading to - reduced Ca2+ flux through the channel - some CCBs alter the "recovery time" of the channel *** different drugs bind on diff location of the alpha1 subunit --> unique behavior for each

Which enzyme is deficient in Fabry disease?

alpha-galactosidase A - Globosides (ex. Globotriosylceramide) in eyes, kidneys, autonomic nervous system, and cardiovascular Sxs: kidney failure, heart failure or stroke, reddish-purple skin rashes, burning sensation in hands * x-linked disease

Lactase

an apical brush border membrane enzyme that cleaves lactose - Lactase (disaccharidase) deficiency-> increased lactose in gut lumen leading to OSMOTIC PURGATIVE EFFECT/fermentation by bacteria causing diarrhea, gas and malabsorption

Hyperemia

an increase in blood flow to different tissues of the body 2 types: 1. Active Hyperemia: (aka functional or exercise hyperemia) - increase in blood flow due to an increase in metabolism ex. increase blood flow to active muscle during exercise *** metabolic theory causes vasodilation and increased flow due to the decreased resistance-> O2 and nutrient supply to tissue as lond as metabolism is increase ** at rest 15-20% of circulating blood supplies skeletal muscle- during vigorous exercise this increases to 80-85% of CO due to active hyperemia- blood shunted from major organs to muscles including heart and skin to promote heat loss ** blood flow will fo where it is needed- ex in treadmill exercise most blood goes to gracilis muscle ** red muscle fibers (type I slow twitch, aerobic) receive greater increase in blood flow than white (type II fast twitch, anaerbic muscles) in exercise 2. Reactive Hyperemia: - a short interruption of blood flow causes vasodilation and increased blood glow * metabolic theory causes vasodilation and increased flow An interupption in blood flow due to a temporary occlusion, which results in a buildup of metabolis waste, leading to vascular smooth muscle relaxation - once flow restored, vasodilation is induced leading to large increase in flow to washout metabolites that accumulated during the period of occlusion- after which blood flow returns to normal as does vessel diameter- the longer the period of occlusion, the longer the subsequent period of reactive hyperemia

Diarrhea

an increase in frequency of defecation, with increase in volume and decrease in stool consistency and often with urgency of stool passage - Objectively, it is defined as increase in stool mass greater than 200grams/day - Can be acute or chronic - Most acute diarrheas are infectious in origin - Diarrhea can be life-threatening (bc dehydration)

Olestra

an indigestible disaccharide with 8 FAs that tastes and behaves like fat in some foods - high FA content mimics taste and feel of TAGs - used to make fat-free fried foods and reduce fat in foods - proctor and gamble solved the leakage and loose stools problem by shortening the length of the attached FAs - FDA warning label was not required after 2003

Anterior Intercostal and Posterior intercostal ARTERIES

anastomose around the midclavicular line ** Post. intercostal a. is a branch of the Superior (supreme) intercostal artery and Thoracic Aorta ** Ant. intercostal a. comes off the internal thoracic a. (1-6th rib) and off the Musculophrenix A. (7th-9th rib)

In the presence of digested protein, AA's stimulate

antrum G cells (indirect) which increases secretion of gastric acid

Mean arterial pressure is highest in the

aorta and falls to low value not much different from zero in the vena cava/right atrium

Cranially the aortic arch arteries arise from the

aortic sac

In crypt cell secretion, Bicarbonate secretion primarily uses an

apical exchanger with chloride, which thanks to chloride secretion here and from the stomach, pancreas, and liver/bild ducts should be in sufficient quantitiy to activate this antiporter * this is essentially the same exchanger as that from salivary and pancreatic ducts - similarly, the basolateral sodium-hydrogen exchanger is essentially the same as that in salivary ducts, EXCEPT here it is only on the basolateral side NOTE: new data indicated that some bicard cross with Cl- using CFTR Net effect: increase in bicarb in lumen and increase in by-product H+ in the venous blood, which will mix with the blood from stomach within the hepatic portal vein (it is all secondary active transport bc ultimately one must pump the sodium out of the cell which had come in transporting Cl-, K+, and H+ across basolateral membrane)

Paneth cells

are cells at the bottom of crypts that produce antimicrobial defensis (they are essential intestinal scavengers) * this is part of the mucosal immunity of the GI

Isomaltase and Sucrase

are enzymes (glycosidases) that form a dimer and work together, deletion of either one will inactivate them both *** these are BOTH secreted by the jejunum (enterocyte)

Vitelline Arteries

are paired blood vessels of the yolk sac wall Adult derivatives= arteries of the gut: - Celiac/ Celiac Trunk (T12 foregut structures) - Superior Mesenteric artery (SMA) (L1 midgut structures) - Inferior Mesenteric artery (IMA) (L3 hindgut structures)

High-pressure baroreceptors reside on the

arterial (high pressure) side of the circulatory system in the carotid sinus and the aortic arch - the aortic depressor nerve, a branch of the vagus (X CN) forms a dense arborization in the aortic arch - the carotid sinus nerves, bilateral branches of the glossopharyngeal nerves (IV) form similar arborizations on the walls of the carotid sinuses ------ Aortic arch measures the pressures that drive systemic and coronary blood flows Carotid Sinus meausres cerebral blood flow ** if these pressures are inappropriate a reflex response is initiated to adjust the pressure levels ***CAROTID SINUS baroreceptors are MOST IMPORTANT for regulating arterial pressure: - carotid sinus receptors respond to pressures randing from 50/60-200mmHg whereas receptors in aortic arch have a higher threshold pressure and therefore are less sensitve *** Maximal carotid sinus sensitivity occurs near the normal MAP, therefore, very small changes in arterial pressure around this "set point" significantly alters receptor firing so that autonomic control can be reset in such a way that the arterial pressure remains very near to the set point

Constriction of arterioles increases

arterial pressure and decreases venous return

dilation of arteriole decreases

arterial pressure and increase venous pressure ** will increase capillary hydrostatic pressure

Individual blood vessel diameter decreases from

arteries to capillaries because of vascular branching - Vessel diameter INCREASES from capillaries to veins due to vessel merging

Total cross-sectional area of each vessel type increases from

arteries to capillaries because of vascular branching - even though the cross-sectional area of a single capillary is very small, the large number of capillaries makes their total cross-sectional area very large

The average (mean) BP decreases from

arteries to capillaries to veins - since blood flows from areas of high pressure toward areas of low pressure, this allows blood flow continuously down a pressure gradient from the aorta to the vena cava

Factors the decrease central venous pressure

arteriolar consrtiction will reduce the volume of blood in the venous system

The main contributor to TPR are the

arterioles and small muscular arteries where pulsatile flow changes to laminar flow

5 whys method

ask why 5 times - till you can find a cause to the problem and then accurately fix it

Mean Systemic Filling pressure

at a RAP of 7mmHg, venous return falls to zero - this is the pressure that would result in the vasculature if all flow of blodo through the circulation ceased and this pressure is generated as a result of the fullness of the circulation (i.e. at blood volume of 5L this will induce stretch on vasculature and generate pressure) - so an increase in blood volume with increase the mean systemic filling pressure

Baroreceptors are sensitive to the RATE of change of BP as well as to the steady or mean pressure- therefore

at a given MAP, decreasing the pulse pressure (systolic-diastolic pressure) DECREASES the baroreceptor firing rate ** this is important in conditions such as hemorrhagic shock in which pulse pressure AND MAP decrease *** the combo of reduced mean pressure and reduced pulse pressure amplifies the baroreceptor response leading to freater responses to increase MAP and pulse pressure

The line flattens at RA pressure below 0mmHg in vascular function curve bc

at pressure negative to atm pressure,vessels begin to collapse limiting the ability to further increase venous return

If the sphincter of the bile duct is closed, bile can

back up along the common bile duct, travel along the cystic duct and be stored in the gallbladder - Up to 50ml of bile can be stored and it is concentrated through the absorption of water and salts

Left heart failure -->

backup of fluid in pulmonary veins and capillaries (backup of fluid from heart to the lungs) --> increased capillary hydrostatic pressure due to increased fluid in capillary beds --> increased filtration --> pulmonary edema

Abnormalities in Carbohydrate digestion and uptake can cause

bacterial overgrowth in large intestine - Carbs are digested and absorbed in the SI Colonic bacteria - increases population if excess carb reaches the large intestine - digest "indigestible" or incompletely digested carbs and fiber - release short acids (acetate, propionate and butyrate) change osmotic pressure - releases gases - increases water retention in gut DISEASES (3 listed): Marasmus is a lack of energy intake (starvation) Sucrase-Isomaltase deficiency (GSID): * Autosomal recessive gene Sxs after eating fruits or grains: nausea, abd pain/cramps, bloating, gas/flatulence, diarrhea (these sxs are caused by malabsorbed sucrose or maltose which draws water into the intestinal lumen producing osmotic diarrhea - intestinal flora metabolizes unabsorbed sucrose and maltose to acids, H2, methane and CO2 Consequences: failure to thrive, slowed growth and development ** Congenital Sucrase-Isomaltase Deficiency: 1/5000 Caucasion and 1/20 Natives greenlander, Eskimo and Inuit NOTE: children with GSID freq. develop sucrose intolerance shortly after intro to solid foods - defects in sucrase activity more common than defects in isomaltase activity of enzyme Lactose intolerance Sxs: nausea, abd pain/cramps, bloating, gas/faltulence, diarrhea 90-95% Asian, Up to 95% Native Americans 15-25% Caucasian Diagnosis: Hydrogen Breath Test to measure H2 levels in the breath

Manual stimulation of the carotid sinuses can mechanically stimulate the

baroreceptors - this increases AFFERENT firing to the NTS - BP and HR are reduced by increasing CN IX activity *** this is the carotid sinus reflex ** this is useful theray for some types of tachycardia - In ppl who have an overly sensitive carotid sinus they may have: Carotid Sinus Hypersensitivity of Carotid Sinus Syncope- in which manual stimulation causes strong stimulation of the vagal nerve leading to large changes in HR and/or BP

At the midpoint between the umbilicus and pubic symphysis (lower one quarter of rectus abdominis) corresponds to

below the arcuate line there is ONLY anterior lamina, made up of the aponeuroses of ALL 3 abd. muscles - there is NO posterior sheath below the arcuate line * transversalis fascia now directly meets the posterior aspect of the rectus abdominis muscle

air appears ____ in an xray

black - bone is very white - grey speckled appearence= feces

Water-soluble lipids (glycerol, short-chain, and medium chain fatty acids) pass through the cell to the

blood - For all the other lipids, absorbed lipid components are recombined into TAGs, phospholipids, and cholesterol esters inside the intestinal epithelium---> these combine into fat-rich structures called chylomicrons *** Chylomicrons are released via exocytosis and diffuse into LACTEALS (lymphatic capillaries, NOT Blood) *** this is the only form of macronutrient ingestion in which monomers are turned back into polymers within the intestinal cell prior to exiting via basolateral exocytosis

Changes in vascular fx curve reflect changes in

blood volume, venous compliance (tone) , arteriolar resistance

Acinar tissue, in the adult human pancreas stain

blue at their base because of the high content of RNA and the presence of nuclei - they are pink "cherry red" at their apex (luminal aspect) where there is a high content of zymogen proteins (inactive form of digestive enzymes) - the nuclei of centroacinar cells are sometimes seen within an acinus - acini secrete pancreatic juice containing enzymes

Lateral folding leads to formation of the

body cavities 1. pleural - higher up 2. pericardial - higher up 3. peritoneal - at level of abd (occurs cranial to caudal)

vessel diameter decreases across the arterial side due to

branching, and is smallest in the capillary networks and across the venous network diameter increases due to vessel merging

Lateral body folding

brings the endocardial heart tubes into the ventral midline where they meet and fuse together to form a single definitive heart tube Tubes meet and APOPTOSIS occurs midline internally to give ONE tube The primitive heart tube wall is now composed of: - inner endocardial layer - middle layer of cardiac jelly (extracellular matrix proteins) - outer myocardial layer (heart muscle) ** NOTE: mesodermal cells WILL migrate from near the devloping liver to eventually form the epicardium ** At the beginning of week 4 the heart is now beating

Lipid-soluble materials absorbed by GI organs

bypass the liver via lymphatic vessels - lipid-soluble toxins a particular danger ** fat-soluble toxins go straight to the heart because liver doesnt have ability to clean it

Vitamin D (cholecalciferol) is integral to the regulation of

calcium and phosphate ---- Low plasme calcium --> increases PTH --> increases Calcitriol (1,25 diOH-D3) BOTH PTH and calcitriol - increase calcium mobilization from bone - increase renal reabsorption of calcium - decrease renal excretion of calcium * calcitriol also increases calcium absorption from the intestine ALL of these effects work to increase plasma calcium

Contraction in vascular smooth muscle mainly occurs via

calmodulin + calcium --> MLC kinase activation--> MLC phosphorylation

Plasmalogens

can constitute a substantial perventage of lipids in some membranes (ex. plasma membranes)- they have similar structure to phospholipids EXCEPT that the end fatty acyl group has an ETHER linkage and a DB rather than an ester linkage (ex. Phosphatidalethanolamine) * these make up 10-20% of the bilayers

People who are lactose intolerant

can neither digest lactose, nor absorb its component monosaccharides * lactose intolerance= most common form of brush border enzyme malfunction - all neonates have a form of lactase that works correctly but is expressed less into adulthood - a second form of lactase is expressed in adulthood - doesnt function well in lactose-deficient pts * clinically a deficiency in lactose digestion at brush borders of duodenum and jejunum results in massive lactose availability for bacteria residing in the terminal ileum and colon - they will ferment this material for energy, result in several waste products including osmotic agents that promote diarrhea and gasses including both methane and hydrogen gas- much of hydrogen gas can be absorbed into bloodstream, where it will be cleared through lungs- quantitiy of H+ in expired air is nnormally minimal but high in lactose deficient pts * diagnostic tool * lactose intolerance more common in populations with long history of not consuming dairy products

___ have the greatest cross-sectional area

capillaries

Dehydration -->

capillary fluid loss, but NO protein loss --> increased capillary colloid osmotic pressure (proteins concentrate in plasma)--> increased reabsorption --> help to maintain blood pressure *** the extra fluid moving from the interstitial space to the blood vessels will help to maintian a normal blood pressure despite the dehydration

After a myocardial infarction there is absence of

cardiomyocyte nuclei *** an infacrtion/necrosis involves the full thickness of the wall "transmural myocardial infacrtion" due to necoris of myocytes

Chylomicrons

carry dietary fat, cholesterol and other hydrophobic compounds

Cremasteric Muscle Reflex

causes rapid elevation of the testis - elicited by stroking the skin of the ipsilateral thigh 1. elicitied by stoking the skin on the medial aspect of the proximal, superior part of the thigh - general somatic afferent (GSA/Sensory): femoral branch of genitofemoral nerve and ilioinguinal nerve 2. contraction of the cremaster muscle within the loops of cremasteric fascia raise the testis to "safety" - general somatic efferent (GSE/Motor): genital branch of genitofemoral nerve ** note testis on same side will rise up - if absent could indicate something is wrong with the spermatic cord (this is used as test for spermatic cord torsion)

Sac is a

cavity within an organism that is enclosed by a membrane and contains air, liquid or solid structures

anchoring structures of the cecum

cecal folds

Esophagus is a foregut derivative, therefore branches from ____ supply the lower thoracic and adominal portions

celiac artery (via left gastric artery) - these are the Ascending branches of the L gastric artery ---- HOWEVER, the Cervial portion of the esophagus is supplied by branches from the inferior thyroid artery and the Middle portion of the esophagus is supplied by esophageal branches from the thoracic aorta *** the venous drainage of the esophagus is clinically important

The common hepatic artery is a direct branch from the

celiac trunk - changes name to hepatic artery proper when the gastroduodenal artery branches off to travel inferiorly

The splenic artery is a direct branch from the

celiac trunk which arises from the abdominal aorta at T12 ** Splenic Artery is the LARGEST branch of the celiac trunk - it is tortuous in nature "wriggly looking" - It lies posterior to the abdominal wall; therefore is immediately posterior to the omental bursa and behind the peritoneum - Courses alon the superior border of the pancreas

Thoracic Wall movements during breathing causes

changes in intrathoracic VOLUME and PRESSURE - lungs move with the thoracic wall -this allows air to get in and out of the lungs Ex. In inspiration - elevation of the lateral aspect of the ribs - sternum moves forward bc of rib elevation - diaphragm descends to increase thoracic capacity

Valsalva Maneuver shows

characteristic changes in aortic pressure and HR * induced when one takes a large breath and attempts to exhale forcible for at least 10 seconds with the clottis closed ex: during times of - defecation (aka at stool) - heavy weight lifting - childbirth ** the sudden bradycardia during phase 4 of valsava maneuver is used as a clinical test for the competence of the baroreceptor reflex

Acute coronary syndrome (ACS)- unstable anging pectoris or a myocardial infarction MI)

chest pain - lasts >20 min and subsides after 2-3 hrs NOT alleviated with nitroglycerins

Calcitriol is derived from the precursor

cholecalciferol via calcidiol * this conversion takes place in the liver and in the kidney in a highly regulated process

Commonly gallstones are formed by the precipitation of

cholesterol crystals - Cholesterol crystals precipitate if the cholesterol in bile increases (supersaturation) or/and bile salts and phospholipids decreases Gallstones may: - be silent - produce gallstone colic - produce acute cholecystitis and associated complications ** NOTE that there are multiple places where gallstones can get stuck

Phosphatidyl choline donates a ____ headgroup to make sphingomyelin from ceramide via simple exchange reaction

choline - sphingomyelin can also contain an ethanolamine headgroup - DAG is the second product (can go back to the normal process- recycled) * sphingomyelin is a major component of myelin, the sheath that surround nerve axons - In Guillain-Barre syndrome, myelin is attacked by inflammatory autoimmune response against myelin sheath

In the colon: Slow, infrequent propulsive movements and frequent segmentation contractions support a

churning effect of even semi-mushy luminal contents - this churning maximizes absorption of liquids - this concentrates those materials left behind into easily stoarble solids - however, too little propulsion wil result in too-hard stools and may produce constipation - so a balance must be achieved- * Control of colonic motility involves many of the same controls as the intestine, using the colonic ENS - intrinsic (enteric), autonomic, and hormonal

circular muscle ___ resistance to flow, and longitudinal muscle ____ resistance to flow

circular muscle- increases resistance to flow longitudinal muscle- reduces resistance to flow ** wherever circular muscle is contracting, longitudinal muscle is relaxed and vice versa

The circulatory system

circulates fluids around the body 2 Divisions: - Cardiovascualr system: heart and blood vessels - Lymphatic system: lymphatic vessels and nodes

MMC (Migrating Motor Complex AKA Migrating Myoelectric Complex) is responsible for

clearing large particles/bodies from the GI tract which are passed in the stool (eventually) - an extended fasting state may be necessary to help clear the quarter (only drink H2O) - may have to refrain from eating anything over a day for something as large as quarter to be passed

Sources of Vit B2, riboflavin:

common in many food, including liver, eggs, yeast, milk, and enriched breads and cereals - Deficiency is rare, and typically only accompanies other vitamin deficiencies. More common in alcoholics Sxs: - Dermatitis - Cheilosis (fissures at the corner of the mouth) - Glossitis (darkened, smooth tongue) - Sore throat * Riboflavin is turned over quickly/excreted in uriner so it can be assayed in the urine

Lipid bilayers act to

compartmentalize many organelles and define the outer boundary

Almost all secreted bile acids are ___ first

conjugated into bile salts first - this increases the solubility of the molecule on one side making it even more amphipathic than unconjugated bile acids ** both primary and secondary bile acids can be conjugated --These conjugated bile acids (bile salts) are almost all ionized at typical intestinal lumen pH meaning they cannot easily be absorbed until they reach transporters in the terminal ileum (enterohepatic circulation) - The side groups which are conjugated are potential nutrients for bacteria- so many forms of bacteria can deconjugate the bile salts back into bile acids in the most distal part of the ileum (they do this in order to use the AA for their own use, not for any particular benefit to humans- the conversion of primary to secondary bile acids appears to be a side effect of this process)

Transverse pericardial sinus

connects BOTH sides of the pericardial cavity - Simple structure when the heart tube began to form during development. At this time it sepeartes the OUTFLOW vessels from the INFLOW vessels of the heart *** The transverse pericardial sinus forms from the degeneration of the dorsal mesocardium (the intiial attachment of the heart to the posterior body wall) - the heart is then suspended by vessels attached at both poles POSTNATALLY: - it is an area of the pericardial cavity located posterior to the aorta and pulmonary trunk and anterior to the superior vena cava ** you can put a clamp behind and infront of these vessels to hault blood flow in certain cardiac procedures

Higher levels of alcohol are degraded by

cyt P450 2E1 (degrades 10-20%) ; this is an ER (endoplasmic reticulum) protein inducible in response to high alcohol levels - cytP450 2E1 produces most acetaldehyde which can cause damage- it also generates free radicals (ROS) - catalase (from peroxisomes) can also degrade some (1-5%) ** rememeber that 75-80% of alcohol degradation occurs in cytosol by alcohol dehydrogenase (ADH)- but this is for moderate levels of alcohol

Melena

dark, sticky, tarry stool containing partly digested blood

crude rate=

deaths occruing during a given period of time / total population

A decreas in arterial BP leads to afferent output from the baroreceptors to

decrease - this reduced stimulation of NTS reduces inhibition of vasomotor center and decreases activationg of the cardioinhibitory area - inhibiton of GABAergic interneuorns in vasomotor center is decreased --> leads to increase activity in the bulbospinal pathway Net effect: increase in symp innervation of the heart and blood vessels and a decrease in parasymp innervation of the heart--> which will lead to increase HR, ventricular contractility, CO, and TPR --> helps to return BP to normal

A decreases in MAP (primary disturbance) leads to a ___ in baroreceptor stretch

decrease ! --> decrease afferent firing to NTS --> decreased NTS activity which can both 1. increase vasomotor activity: increases SNS which increases HR, increases contractiligy which increases SV (increases HR and Increased SV lead to increases CO), also increases TPR- (increase in CO and TPR lead to increase in MAP) 2. decrease cardioinhibitory activity: which decreases PNS activity leadins to increased HR which also leads to increased CO and increased MAP

Increased arteriole resistance (tone) --> decreased venous volume --> decreased driving pressure -->

decreased venous return ** no chaneg in mean systemic filling - as the change in arteriolar resistance is only very small this only has limited effect on relationship between VR and RAP

PV loop changes in LV heart failure (Systolic Dysfunction)

decreased: - inotropy - slope of ESPVR line - SV - ejection fraction (SV/EDV) results in Heart failure with reduced ejection fraction (HFrEF) - stroke work increased: ESV and EDV (this is why SV is decreased) ventricles more compliant ** no change in EDPVR bc the dysfunction is NOT diastolic

Increased right atrial pressure -->

decreases driving pressure from central veins to RA--> decreasing venous return ------ decreased RAP --> increased driving pressure from central veins to RA --> increasing venous return ** if there is no change in CVP

One target for cardiovascular pharmacology is

decreasing peripheral vascular resistance (PVR) ** Calcium Channel Blockers ("Vasodilators") can be used: - Dihydropyridines (DHPS): Nifedipine and Nicardipine - Non-dihydropyridine (Non-DHPs): Verapamil and Diltiazem

All CCB agents work by

decreasing vascular resistance and increasing coronary blood flow Vasodilatory potency: DHPs> Verapamil > Diltiazem DHPs: - at increase dose --> negative inotropy (probably too high of a dose) - sympathetic reflex modest unless rapid IV infusion Non-DHPs: At dose for peripher vasodilation, decrease effects on chrono, dromo, and inotropy are MUCH more signifanct than DHPs cause - vasodilation+ chronotropic effects --> limited reflex tachycardia - negative inotropic effects offset both decrease afterload and increase adrenergic tone **** Verapamil is a moderatley more potent negative inotrope than diltiazem

The pylorus of the stomach has

deep pits and short glands (branched and coiled) - mucous-secreting cells predominant (bc usually not supposed to push things through pylorus- but sometimes you have to i.e. swallowed quarter) Enteroendocrine cells (EEC) are common: - G cells which secrete gastrin (stimulates secretion of HCl by parietal cells) - D cells which secrete somatostatin (inhibits gastrin)

Protein and energy malnutrition (PEM) is often accompanied by

deficiencies of micronutrients, electrolyte imbalances, and metabolic disorders - Vit deficiencies uncomplicated by other partial deficiencies uncommon (i.e. usually DONT get a Vit. deficiency that occurs in isolation (pt that is malnutrition is unlikely to only lack one vitamin) - Fat malabsorption due to liver/biliary dysfunction are main causes of fat soluble vit deficiencies (DEKA) - Vit excess is responsible for toxic accumulation of Vit A, D, K, Niacin, and Pyridoxine (B6) - Most water soluble vit. fx. as essential coenzymes, featuring unique chemical reactivity - Fat soluble vitamins have more varied function (ligands for transcription factions- mostly nuclear receptors) - Widespread use of supplements by normal individuals is generally safe, but unnecessary

The liver parenchyma is organized as thousands of small (~0.7x2mm) hepatic lobules in which hepatocytes form hundreds of irregular plates arranged radially around a small central vein. The hepatocyte plates are supported by a

delicate stroma of reticulin fibers * NOTE: peripherally each lobule has 3-6 portal areas with more fibrous CT, each of which contains 3 interlobular structures that comprise the portal triad (bile ductule, portal venule, hepatic arteriole)

In the abd cavity, the transverse mesocolon can be used to

delinate the boundary between supracolic and infracolic abd compartments Supracolic Viscera (below the diaphragm and ABOVE the transverse mesocolon) - distal esophagus - stomach - duodenum: 1st and part of 2nd - pancreas - spleen - liver - gall bladder Infracolic viscera - small intestine: duodenum 2nd, 3rd, 34th parts, jejunum, and ileum - cecum - appendix - large colon - rectum - anus

blood flow velocity falls as

diameter of vessels decreases

Mean arterial pressure (MAP)=

diastolic pressure + 1/3 (systolic pressure- diastolic pressure) *** IN systemic circulation MAP is effectively driving pressure since the RA pressure is so low *** Pulse pressure= Systolic pressure- Diastolic pressure *** The magnitude of pulse pressure is influenced by condidtions that alter the volume of blood ejected by the heart (stroke volume) and/or arterial compliance SO MAP= Diastolic pressure + 1/3 (pulse pressure) ------------ Arterieal BP oscillates between high pressure systolic and lower pressure diastolic - in systemic arterial system the pressure normally fluctuates between 120-80mmHg (120/80) while in pulmonary arterial system the pressure fluctuates between 25 and 8 mmHg (25/8)

Insufficiency in Fat Soluble Vitamins can result for

dietary reasons - More general insufficiency can arise from poor absorption - This can be indicated from steatorrhea (greasy stools) due to exocrine pancreatic insufficiency or a blocked bile duct (the latter turns stools pale or grey) VitA (retinol): from plants may cause night blindness if deficient VitD (cholecalciferols): form fortifies milks can lead to rickets in children or osteomalacia in adults if deficient VitE (tocopherol): from Veg and seed oil- can lead to abetalipoproteinemias if deficient (this is rare) VitK: from plants and bacteria can lead to Hemorrhagic disease of the newborn or Common: Koagulation, or fat malabsorption in adults(rare) if it is deficient Vit F (refers to essential FAs linoleic and linolenic acids- VitK not generally used as term as they are considered macronutrients which are req. in large quanitities in the diet)

Vit B9, Folate is converted to

dihydrofolate and tetrahydrodolate (THF) by dihydrofolate reductase - THF is the active form and participates in 1-carbon (methyl group) transfers - Folic acid consists of pteroic acid (pteridine plus para-aminobenzoic acid) plus 1-7 gamma-linked glutamate residues *THF is critical for purine synthesis, thymidine synthesis (DNA), and AA synthesis (serine, methionine) * Dihydrofolate reductase is inhibited competitively by methotrexate (clinically methotrexate is commonly used for chemotherpay to inhibit growth of rapidly dividing cells) * methotrexate can also treat psoriasis, rheumatoid arthritis and neoplastic diseases * Sulfonamides block folate synthesis in bacteria and threby decreases the synthesis of nucleotides nedded for replication of DNA NOTE: carboxyl groups are not transferred by THF. Rather, bicarbonate-derived carboxyl groups are transferred by biotin and phyllochinon (VitK) - Folate is absorbed by brush-border enterocytes- some drugs inhibit absorption: phenytoin, alcohol, oral contraceptives

Erosive Dysbiosis usually results from organisms

directly attaching to and damaging cells lining the organ - the organism deprives the gut cells of nutrients in most cases - destruction of the brush border, reducing absorption, is a common consequence of dysbiosis - NTs and other metabolites secreted by the biome increase water permeability as well increasing the ability of some species to cross into general circulation

iron is mostly absorbed in the

duodenum ----- Mechanism: - iron ions come in 2 main forms, Ferric (Fe3+) and Ferrous (Fe2+) - only the Fe2+ form can be absorbed from the intestine, MOSTLY duodenal In contrast, Fe3+ is the usual stoarge form and the form transported in the blood - Ferritin is used to store iron in iron excess - Iron-binding proteins help process Fe3+ and deliver it to the blood protein transferrin ------- Iron is needed in small quantities for the production of functional hemoglobin- it is potentially TOXIC so its absorption into the blood is tightly controlled (hephaestin has some temporary storage in these cells but dont live very long- ---- Like calcium ion, absorption of ferrous iron from the lumen to the enterocyte cytoplasm is limited by its transport maximum - excess iron in the intestinal lumen will pass into feces UNLIKE calcium, once absorbed into the enterocyte, ferrous iron is converted to ferriv iron and stored within the cell (such that passage across the basolateral membrane into the blood is also subject to control) ** remember that the cells doing the absorption have a limited lifespand of only a few days- if iron ions stay within the cell too long, the cell will die and the iron will be re-released back into the intestinal lumen again

Most of the absorption of carbohydrates, proteins and lipids occurs in the

duodenum - moderate absorption in jejunum - low absorption in the ileum (by this time most carbs and lipids have been absorbed) **** given that intestinal motility keeps moving materials in an anal direction, the longer it takes to fully digest a given type of food, the further a long the GI it will be absorbed * there is also a significant surface area for absorption in the early part of the small intestine

In the fasted state, half of the bile flows directly into the

duodenum and half is diverted into the gallbladder

calcium is absorbed in the

duodenum, jejunum, and ileum * basically absorbed wherever you can get a channel

Pts with heart failure will most likely complain of

dyspnea and fatigue

Diverticulosis is common in

elderly and located mainly in the SIGMOID colon - the rectum is always spared - may run in families Predisposing factors for diverticula formation: - low fiber diet - higher-amplitude contractions - constipation - weakness in the colonic wall

In crypt cell secretion, transcellular Cl- secretion is used to create the

electrochemical gradient to drive paracellular sodium secretion - those two then create an osmotic gradient to drive water secretion - NaCl and water secretion can occur at low levels through the length of the GI. - NOTE that CFTR is the apical protein whose activity drives all the rest of crypt cell secretion (when not in use, most CFTRs are stored in intracellular vesicles in an inactive state) - when note in use, excess CFTRs are sequesters in intracellular vesicles - the triple transporter NKCC1 role is bringing in Cl- to be secreted across the apical membrane (secondary active transport bc. the sodiudm-potassium pump is used to remove excess sodium back into the ECF)

Bile is a yellow-brown (or green) fluid that aids in the

emulsification of fat * Bile is produced in the liver ** Gallbladder is the organ that STORES and CONCENTRATES the bile

Hypertrophy

enlargement due to enlargement of individual cells Ex. Body builders do not have an increase in muscle fibers BUT rather an increase in muscle fiber size

The cardia of the stomach has

equal pits and glands - this is where the esophagus dumps things in (sometimes you can feel pain here and confuse it for heart pain) - Its epithelium provides mucus via the surface mucous cells which protects against reflux - The glands are long, branched, coiled: they have mucus-secreting cells, stem cells and entroendocrine cells (EEC) * NOTE: there are few parietal cells (which produce HCl) that are present *** in this layer of the stomach: mucus secretion is the main focus

Normally the esophageal and gastric mucosa are

esophageal muscosa= squamous epithelium gastric mucosa= columnar epithelium

The relationship of the heart to ribs and sternum is important in

evaluation what structures may have been damaged with penetrating wounds ex. Stabbing, shotgun Some examples of "Danger Areas" - Left of 1st intercostal space: can damage pulmonary artery - Left 2nd intercostal space (parasternal border): left atrium - Left 3rd-5th ribs (parasternal border): right ventricle - Right 3rd-6th ribs: right atrium

Lymph

excess interstitial fluid found in tissue spaces - clear to white fluid, rich in proteins - lymph can contain lymphocytes but does NOT contain RBCs (except in pathology)

Large Ventricular Septal Defects can cause

excessive pulmonary blood flow (as L to Right shunt) - can lead to pulmonary hypertension and cardiac failure in infancy

Like the stomach, the rectum is capable of

expanding to allow for entry of material from the ileum and then storage of those contents as they are processed into solid waste and it is a convenient time and place to defecate - at that point, the large intestine is capable of generating a powerful contraction to force solid waste (now fecal material) out of the body- before that point, the intially-liquid material must be moved along the length of the colon, being solidified along the way - In meantime, motility of large intesting is critical to ensure the initially-liquid contents entering the cecum form the ileum are thoroughly mixed so that when the feces are done, they are the same consistency from soft to very hard throughout the entire fecal mass - similarly, absorption of bacterial-produced fatty acids cannot take place unless motility of the contents puts the fatty acids in proximity of an absoprtion site at the gut wall

Bile Canaliculi are found in the

extracelluar space between two adjacent hepatocytes; sealed by zonula occludens (prevents leaking) and transport bile - they form a continuous, polygonal branching system within the lobule - they joinn the bile ducts in the portal triad via short squamous to simple cuboidal canals of Hering - Near the perophery of each hepatic lobule, many bile canaliculi join with the much larger bile canals of Hering, which are lined by cuboidal epithelial cells called cholangiocytes - these canals soon join the bile ductules in the portal areas and drain into the biliary tree **** such canaliculi run between the cells of the hepatocyte plates in the hepatic lobules and carry bile toward the portal areas where the canaliculi join cuboidal bile ductules

Medicaid

federal and state assistance program that paid by federal state and local taxes to benefit ppl with low incomes - participant pay very little or no part of coverage

Composition of pancreatic juice is ______

flow-dependent - Reflects changing proportions of acinar and ductal secretions - There is always a low basal secretion rate featuring mostly acinar fluid rich in chloride and low in bicarbonate - At the highest flow rates, pancreatic juice is mostly from ducts, high in bicarbonate and low in chloride *** the same hormone that promotes more flow (secretin) also promotes more bicarbonate in the juice ----------- Similar to what happens in the stomach, at "rest" with no acid in the duodenum, theres is no need to secrete either a large volume of pancreatic juice or a great quantitiy of bicarbonate - the secretion that does take place is basal, unstimulated, and containing almost plasma-equivalent levels of sodium chloride - it is functionally acinar cell primary secretion alone with just enough ductal secretion to prevent inappropriate digestive enzyme activation in the ducts ** when secretory rate rises, acinar flow rises but ductal flow rises so much more that the chloride levels drop to one thired of the unstimulated level and the bicarbonate level rises to 5x that of the blood - both sodium and potassium levels remain essentially unchanged

The peritoneal cavity is formed during

folding of the embryo - head and tail folding leads to constriction of the yolk sac and demarcation of the for-, mid- and hindgut regions

Mechanical and Chemical Digestions break

food chunks and large molecules into isolate, small, absorbable molecules - Mechanical digestions: motility in mastication, gastric motility, intestinal motility (segmentation contractions)- "grinding" - Chemical digestion: digestive enzymes "break molecules apart" - Absorption: transports in epithelium - Water soluble molecules: transported in blood to liver - Lipid soluble molecules: repackaged into chylomicrons- tranported in lymph (bypass liver) ** NOTE: the digestive system is nonspecific- it will break down any nutrients - some larger meals will take longer * combined processes of mechanical and chemical digestion ensure that all are absorbed into the bloodstream, mostly for a direct trip to the liver for further metbaolic processing

In termic effect of food

food ingestion stimulates metabolism - this is equivalent to 5-10% of energy of the food consumed ex. if an individual consumes 2,000 Cal, energy used in digestions (expenditure) is expected to be= 200 Cals (10% is typically used in calculations) - only 1,800 Cal are left to go toward RMR and activity and storage

The Joint commision (TJC) are responsible

for giving hospitals their accredidation ** improvemtn due to external measuring and monitoring ** TJC christens a hospital as a top performer if it earns that distinction in at least 1 of 9 of the core measure sets of care: - heart attack - heart failure - pneumonia - surget - chidrens asthma - inpatient psychiatric servies - venous thromboembolism - stroke - immunization

Lymphatic vessels

formed by converging lymphatic capillaries - afferent lymphatic vessels run TO lymph nodes - efferent lymphatic vessels run FROM lymph nodes Can resemble veins: - lined by endothelial cells - thin layer of smooth m. and adventitia is present in the walls - possess valves HOWEVER lymphatic vessels: - thinner walls - no distinct tunics - more valves - no RBCs - can be dilated with lymph

Original position of the foramen ovale is represented postnatally be the

fossa ovalis

Remodeling of the Left atrium occurs simultaneously with that of the right. A singl pulmonary vein develops as an outgrowth of the posterior wall of the primitive Left atrium and it divides into

four branches (1-4) that gain connection with the blood vessels supplying the developing lungs - During further development, the main stem and proximal parts of its branches become reincorporated back into the posterior wall of the left atrium forming the smooth portion (**Smooth part of Left atrium is derived from embryonic pulmonary vein) ----- The primitive atrium forms the trabeculated (rough) portion (as in the right atrium)- this equates to the auricle of the left atrium

Hematochezia

fresh, brigh red blood in the stool

Parietal cells (AKA oxyntic cells) are only found in the

gastric glands - they are more numerous in the upper half than in the lower half of the gland - have intracellular canaliculi visible at TEM level - they produce HCl and intrinsic factor (IF): IF binds VitB12 uptake in the ileum - Lack of IF leads to gastric atropy and pernicious anemia *** on staining parietal cells have an eosinophilic cytoplasm, central nucleus, and "fried egg" appearance ** parietal cells are found mostly in the neck of the fundus/body of stomach but also in the base

Inflammation of the VISCERAL peritoneum causes

generalized, referred pain that is felt in the associated dermatome of the organ

When you stand, blood pools in the lower extermities bc

gravity and high venous compliance --> this causes a reduction in venours return, cardiac output, and mean arterial pressure --> initiates the baroreceptor reflex --> effects effector organs by increasing HR, contractility, and TPR --> results in VR, CO, MAP being restored to normal ** water bottle analogy

Poor motility in colon causes

greater absorption, and hard feces in transverse colon cause constipation * poor motility= to much H2O absorption

Over the length of the capillary, filtration is_____ than reabsorption

greater! so apprx. 10% of the filtrate (2L/day) is filtered but not reabsorbed - this excess fluid is retured to the circulation via the lymphatic system

If atresia/stenosis is in the duodenum CAUDAL to opening of the main pancreatic duct (ex. 4th part of the duodenum) then vomit will be

green in apperance - bc bile will enter into the SI and get past the constriction IF the atresia/stenosis occurs cranially to the opening of the main pancreatic duct (ex. First part of the duodenum)- vomit will NOT be green in color ** In pyloric stenosis vomit will NOT be green-colored as obstruction is proximal to the bile duct

The ___ "guides" gonads inferiorly

gubernaculum * for males the gonads are the testes * females the gonads are the ovaries ** the gubernaculum becomes the scrotal ligament

Copper is important for

healthy nerves, joints 80-110mg/person Daily req. of 1-3mg/day Deficiency is RARE - Copper is used as a cofactor in oxygen binding enzymes (it is req. for cytochrome c oxidase, lysyl oxidase, ferroxidase (ceruloplasmin), dopamine oxidase, tyrosinase (produces melanin), superoxide dismutase (removes superoxide toxins) Sources: - meats, shellfish, nuts and cereals

What part of antibody does C1q bind to

heavy constant domain (this is the complement binding site)

HIgh pressure baroreceptors monitor cardiac output and therefore blood pressure

high cardiac output --> increases stretch of high pressure baroreceptors --> increased afferent signals to NTS --> regulation of effector organs to reduce blood volume/pressure

Long-term (chronic) baroreceptor stimulation

high-pressure baroreceptors are NOT effective in long-term BP control - baroreceptors adapt to chronically elevated BP and no longer signal the brain that pressure is elevated Ex. Chronic Hypertension: in this case compliance of the walls of aortic arch and carotid sinus decreases, and sensitivy of the receptors to stretch decreases- they adapt to elevated pressure and no longer signal the brain that the pressure is elevated "" baroreceptors reset to this new level"" *** this is why long term regulation of pressure involves regulation of blood volume by the renal system Renin-Angiotensin Aldosterone System (RAAS): 1. constrict vessels (AT1 receptors) 2. ADH release from posterior pituitary (stimulates recovery of H2O) * decreased BP --> renin from kidneys--> angiotensinogen from liver --> angiotensin I --> angiotensin II via ACE enzyem in lungs ------ Ang II 1. constricts resistance vesels --> increases MAP 2. aldosterone release from adrenal cortex --> increases sodium and fluid retention 3. ADH release --> increases fluid retnetion by kidneys 4. Stimulates thirst centers in brain

Digestion is the

hydrolytic breakdown of biomolecules into monomers * it is done using the 4 classes of major GI enzymes: - proteases: proteins --> AAs, di- and tri-peptides - amylase or glycosidase: carbs --> sugars, di- and tri-saccharides - lipase: fats --> fatty acids and mono glycerides (diacylglyceride being most common) - nuclease: nucleic acids --> sugar, phosphates and bases *** ALL these reactions are hydrolysis reactions - water is used to cleave the covalent bonds - it water is NOT available in food it is acquired via the blood stream

Saliva is

hypotonic

Partitioning of the Outflow Tract

i.e. separation of the truncus arteriosus and conus cordis (which is the part of the bulbus cordis that tapers to merge with the truncus arteriosus) - Neural creat cells migrate and invade the truncal and bulbar ridges - these ridges grow and twist around each other in a SPIRAL FASHION and eventually fuse to form the AP septum AP septum divides the truncus arteriosus and conus cordis into 2 main structures: 1. aortic sac and - the aortic sac then forms R and L horns which give rise to the branchiocephalic artery (trunk), ascending aorta, and proximal segment of the aortic arch 2. Pulmonary trunk ** If all goes smoothly- this results in connecting the aorta to LV , and pulmonary artery to the R ventricle REMEMBER: truncus arteriousus gives rise to the aorta and pulmonary trunk

In achalasia there is

idiopathic destruction of inhibitory motor neurons of the myenteric plexus - which are normally used to relax the lower esophageal sphincter (LES) - their absence results in- chronically high smooth m. tone in the LES, functional narrowing of the lower esophagus, and peristaltic failure throughout its length - there is a dilated esophagus proximal to a narrowed, tapered area at the gastroesophageal junction ("birds beak") - Pts complain of food "sticking in the chest" after swallowing- and a heavy sensation in the chest that may be painful- and might be confused with angina - they may also regurgitate their food (sometimes at night, and may lose weight)

L1 divides to form the

iliohypogastric and ilioinguinal nerves - Iliohypogastric nerves (R/L) : innervate the skin over the iliac crests, upper iliac (inguinal) regions, and hypogastric (pubic) regions. They also give nerve supply to the internal oblique and transversus abdominis muscles - Ilioinguinal nerves (R/L): innervate the scrotal skin in men and labia majora in women, the area over the pubic bone, and the medial portions of the thigh. They also innervate the internal oblique and transversus abdominis muscles ** associated with reproductive system

health resources and service administraton (HRSA)

improce access to health care services fro ppl who are uninsured, isolated or medically vulnerable

Bulk Flow Law

in a steady state, fluid flow between 2 points is equal to the diff in pressure between the 2 points divided by the resistance to flow Flow= (P1-P2)/R ** analogous to Ohms law (I=V/R) In systemic circulation: Flow- LV output (i.e. cardiac output) P1-P2= aortic pressure- RAP (i.e. MAP) R= total resistance to flow imposed by ALL blood vessels ins systemic circulation (the TPR or SVR giving- CO=MAP/TPR) For systemic circulation you get: MAP= COxTPR or TPR=MAP/CO For pulmonary circulation: CO= (MPAP-LAP)/ PVR (MPAP-LAP)= COxPVR or PVR= (MPAP-LAP)/CO ------- Total blood flow in pulmonary or systemic circ. is cardiac output (CO)- the volume of blood pumped by each ventricle each minute (L/min) ** bc these two circulation are in series, blood flow/min is very similar in both In systemic circulation - driving pressure is the difference in pressure between the aorta and the RA ** since the aortic pressure is pulsatile (fluctuates between 120-80mmHG), the MAP is substituted for aortic pressure in this equation

Fluid within the bile canaliculi flows _____ as blood through the sinusoids

in opposite direction as blood - this bile fluid drains into bile ducts for further processing and, if stored in the gallbladder- for further concentrating NOTE: bile canaliculi in the liver are continuous with the bile ducts outside of the liver --- NOTE: the canalicular membrane is separate from the sinusoidal membrane and the transporter proteins on each are different - essentially, the sinusoidal membrane would be called the basolateral membrane anywhere else, and the canalicular membrane would be called the apical membrane (DONT let these diff. names confuse you on the exam!)

Steatorrhea

inability to uptake lipids properly - lipid and fats excreted in feces - malabsorption of lipid Stool changes: - fatty stool - may float - lighter color - foul smell - loose - larger than normal volume Disease states causing a lack of lipid uptake include: - exocrine pancreatic insufficiency - lipase deficiency - bile salt deficieny - blocked/inhibited lipases - reduced small intestine - use of olestra or orlistat * Artificial fat Olestra * Lipase inhibitory Orlistat ** these are both direct competitive inhibitors to pancreatic lipase, phospholipase A2, lingual lipase --> which prevents digesting those FAs if cant digest and make free FA --> CANT digest --> go into gut and increase H2O get more diarrhea ** Xenical and Alli are over the counter capsules of Orlistat ** Weight control industry has introduced and market ways to have your fat, eat your fat but dont absorb all of the fat * Impairs fat soluble vitamin uptake (A,D,E,K) because they partition into excrete fat as well as absorbed fat

relative risl (RR)

incidence in exposed/ incidence in unexposed ** relatic risk > 1: risk factor increases likelihood of disease ** relative risk = 1- no effect of risk factor on developing disease

absolute risk reduction (AR)

incidence rate in exposed - incidence rate in unexposed

evidence based medicine

includes best research evidence, physicians clinical judgement and pt preferences

Appendix may rarely be in a sub-hepatic position due to the

incomplete rotation of the midgut

In skeletal muscle blood flow, active hyperemia can

increase blood flow by as much as 20-fold - in phasic activity, such as running, active hyperemia is predominant - with occlusive muscle activity such as liftin weights, reactive hyperemia is predominant ** both due primarily to adenosice and K+

Cardiac function curve

increase in venous retunr --> increases RAP --> increased ventricular filling and EDV --> increased cardiac output

Increased symp tone, Angotensin activation, and Renin secretion can all

increase peripheral resistance (TPR) in hypertensive patients

effective therapy prolongs life but doe not offer cure

increase prevelanace

Effects of standing motionless (>5min) on BP

increase venous pressure in LE--> increases venous capillary hydrostatic pressure in LE --> increase net filtration in LE --> decrease venous blood volume --> decrease CVP --> decrease VR and CO --> decrease blood to brain --> syncope ** when standing motionless for over 5 min syncope may occur

Hypertension is commonly associated with

increased PVR - in vascular smooth muscle, if we decrease intracellular calcium then we decrease contraction (arteriolar dilation) which leads to decreased PVR DHPs: will also see IMPROVE inotropy/CV function due to 1. minor symp response increase (minor increase in HR/CO) 2. reduced afterload *** Longer acting formulation less likely to spike SNS reflex NON-DHPs absent/minimal SNS reflex due to direct negative chronotropic effect of these drugs ---------- CCB for HTN may be best in AA and elderly population as they typically have a lower renin status - they are possible the best agent in HTN that is isolated to just the systolic component with non-DHPs, caution when used with a beta-blocked: additive effects could lead to a heart block

Changes in contractility shift the cardiac function curve

increased contractility shifts the curve up and to the left - occurs via increased symp stimulation, increased circulating epinephrine and positive ionotropic drug (ex.cardiac glycoside) - ahnges in preload (EDV) increase force of contraction - increased intracellular calcium *** heart is hypereffective (enhanced)- due to extrinsice mechanism, i.e. originating outside the heart muscle decreased contractility shifts curve down and right - occurs via decreased symp stimulation, loss of ventricular tissue (severe MI or in case of HF , negative ionotropic drugs ** heart is hypoeffective (depressed)

In passive Potassium secretion in the colon

increased sodium/water absorption has a side effect of making the colonic lumen more negatively charged. If the electrical gradient between ECF and lumen fluid is large (-25millivolts), paracellular potassium secretion increases

increase in blood volume leads to increased driving presse and thuse

increased venous return ** increase in blood volume shifts vascular fx curve up and to the right (vice versa)

decreased venous compliance (venous constriction) --> venous reservoir displaced to heart -->

increased venous return ** a decrease in venous complian shifts vascular fx curve up and to the right (and vice versa)

decreased arteriolar resistance (tone) --> increased venous volume--> increased driving pressure -->

increased venous return ** no change in mean systemic filling

Low pressure (or cardiopulmonary receptors) baroreceptors monitor venous return (volume receptors)

increased venous return --> increase stretch of low pressure baroreceptors --> increased afferent signal to NTS --> regulation of effector organs to reduce blood volume/pressure *** since the venous side of the systemic circulation is a blood-volume reservoir these receptors are aka volume receptors- in general they sense the "fullness" of the circulation ***** a decrease in volume would DECREASE afferent nerve activitiy leaving the receptors

An increase in arterial blood pressure, afferent output from the baroreptors

increases! --> increased stimulation of NTS--> NTS efferent output increases --> further reduces vasomotor area activity and increases the activity of the cardioinhibitory area - inhibitory of vasomotor area --> reduced TPR (vasodilation), HR, and contractility - increased activity of cardioinhibitory area --> negative chronotropic effect on heart (reduced HR) ** All of this combine to reduce HR, contractility, CO and TPR --> reducing BP and removing the source of baroreceptor stimulation

Capillaries have a decrease in

individual capillary vessel diameter, but it is the overall increase in total-cross sectional area of the capillaries that is responsible for the decrease velocity of blood flow in the capillary beds - physiologically, it is the enormous amount of branching (large cross-sectional area) that is decreasing the velocity of flow in capillaries

In males the testes start high up in the abd wall and then end up in the scrotum because

inside the body the temperature is too high for sperm production so it must move outside to cooler temperature where sperm can be properly produced ** the testes do this by hitching a ride with the gubernaculum

Parietal layer of peritoneum covers and lines the

internal walls of the abdomen- pain is well LOCALIZED (very sensitive)

Dietary Reference Intake (DRIs)

is a general term for a set of reference values used to asses and plan nutrient intakes of normal, healthy individuals It includes: - Estimated Avg. Req. (EAR): daily intake of specific nutrient estimated to meet the req. of 50% of healthy ppl in an age and gender-specific group- it is used to calculate the RDA - Recommended daily allowance (RDA): avg. daily level of intake sufficient to meet the nutritional req. of nearly all the ppl (97.5%) - Adequate Intake (AI): assumed to ensure nutritional adequacy- it is based on an estimate - Tolerable upper intake level (UL): at a rate above this risk for adverse effects increases ex. overload of vitamins

Platelet activating factor (PAF)

is a lipid that is similar to phosphatidyl choline and to plasmalogens - but linkage is slightly different- in this cae with the third position FA linked with an ether, but there is NO DB

Sucralfate

is a salt of sucrose complexed to sulfated aluminum hydroxide - In acidic environment, aluminum is cleaved and negatively charged sucralfate binds to exposed positively charged proteins in ulcerated tissue - May also stimulate local production of prostaglandins and epigermal growth factor Pharmacokinetics: - oral - take 1hr before meals (needs acidic environment) - duration of action ~6hrs Adverse Effects/Toxicity: - Bezoar formation (once aluminum cleaves it can get sticky) - Constipation - Aluminum toxicity (renal failure patients) Drug Interactions: - May bind and impair absorption of other oral drugs - avoid concomitant acid reducers Clinical Uses: - Prophylaxis of stress ulcers - Disorders of mucosal inflammation or ulceration

health maintenance organization

is insurance plan that keep costs low

Which cardiovascular disease is characterized by highest mortality rate?

ischemic heart disease

Why is nutrition important?

it is important because poor nutrition has been at the route of major national health issues - obestiy - metabolic sydrome - diabetes - cardiovascular disease - hypertension - cancer And good nutrition can aid in providing a healthy lifestyle - via proper dieat and physical exercise - correcting existing undernutrition gap in 15% of US households

folic acid is mainly absorbed in the

jejunum

Beta-glycosidase (glycosylceramidase and lactase) is a glycosidase (enzyme) that is secreted by the

jejunum (enterocyte)

Retrograde peristalsis usually begins in the

jejunum, or perhaps the ileum but definitely caudal to the opening of the bile ducts - at such times, one will vomit intestinal contents, gastric contents, AND BILE with its characteristic color and bitter taste - by definition, such contents moved from the intestinal tract into the stomach prior to the final emesis stage * In majority of cases, vomiting only involves emesis of gastric contents

Endometrial cancer begins in the uterus, uterine cancer cells spread to the

labium majus via lymphatic vessels travelling with the round ligament of the uterus

Circular folds (plicae circularae) create a

large internal surface area

Lymphatic capillaries

larger than blood capillaries and irregular in shape - begin as blind-ended vessels - consist of a single layer of overlapping endothelial cells that rest on an incomplete basal lamina - overlapping endothelial cells lie across opening though which lymph passes (overlapping cells act to prevent backflow of lymph) - anchoring filaments, containing elastic fibers, connect lymphatic capillaries to surrounding tissue and keep openings patent

Bursa:

latin word for bag or purse and is defined as being a fluid-filled sac or sac-like cavity

The Jejunum is found mostly in which abd quadrant

left upper quadrant (LUQ) - accounts for proximal 2/5ths (2.5m) - intraperitoneal (highly mobile and attached to the post. abd wall by the root of the mesentery - specialized epithelial lining for absorbing nutrients that have been digested - gradual change --> no clear change of when the ileum begins

Excess motility in colon causes

less absoprtion and diarrhea or loos feces * excess motility= diarrhea

The lesser curvature is connected to the liver by the

lesser omentum (LO) - The greater omentum (GO) is attached to the greater curvature (GC) of the stomach and the transverse colon: it is the policeman of the abd- it protects other organs from inflamed or diseased organs

Pacemaker zone

lies on the greater curvature of the stomach at the border of the body and the fundus - it contains special cells that drive slow waves of smooth m. contraction frm that point down toward the pylorus - the pace of slow wave muscle contractions is 3-4 waves/min. in the stomach * this pacemaker is important in the ENS ** NOTE: that at level of esopageal sphincter if one were to cutt a transverse plane- everything superior to this would be the fundus of the stomach

Acute diarrhea

like constipation, it is a symptom/sign, NOT a disease - it implies an increase in stool volume and diminished stool consistency - excessive secretion of water and/or excess motility of the colon leads to stools that are excessively wet and high in volume and/or frequency - can be associated with other conditions such as inflammatory bowel disorder or certain GI infections, particularly those with toxins

positive predictive value

likeluhood that someone who testes positive for disease actulaly has disease this is affected by disease prevalance - increased prevalence = increased PPV - decreased prevalenece= decreased PPV

Cholesterol is synthesized mainly in the

liver *** the first steps are the same as for ketone body synthesis, however, ketone bodies are synthesized in the mitochondria while cholesterol synthesis is initiated in the cytoplasm Liver synthesis balances delivery from: - chylomicron remnants - HDL and Loss to: - bile synthesis and excretion - VLDL * First step is synthesis of HMG-CoA (begining with 2 Acetyl CoA using the enzymes Thiolase and HMG-CoA synthase--> eventually getting HMG-CoA (the key start point for cholesterol AND ketone body synthesis))

Water-soluble materials absorbed by GI organs go directly to the ____ for processing

liver - "first-pass" metabolism of nutrients, etc. - kupffer cells destroy invading cells, etc

The pancreatic veins drain blood from pancreas and as they are part of the portal system, they will first drain to the ____

liver before heading to the heart - Majority of veins follow the arteries, most veins will drain into the Splenic Vein - Some veins, particularly around the head of the pancreas, will drain via the superior mesenteric vein *** Ultimately these both drain into the Hepatic Portal Vein REMEMBER: Splenic Vein + Superior Mesenteric Vein= Hepatic Portal Vein

The Lesser Omentum connects the

liver to the LESSER curvature of the stomach and the first part of the duodenum can be divided into two ligaments: 1. hepatogastric: thin and membranous portion 2. hepatoduodenal: thick free edge containing the portal triad

The Dense CT from the Liver (Glisson's) capsule invades the underlying liver to break it down into

lobes and lobules - Lobules are composed of a hexagonal mass of anastomosing plates of hepatocytes which radiate from the central vein to the periphery - At the periphery Portal Canals are found (portal tracts or areas or periportal space) contain branches of the portal vein, hepatic artery and bile duct as well as lymph vessels ** the periportal space/space of Mall (between CT and hepatocytes) is the site where lymph originates

Coronary blood flow is almost entirely controlled by

local factors - limited SNS control becuase few alpha-1receptors are present Metabolic control: - active hyperemia: adenosine and hypoxie (low O2) - reactive hyperemia: compression of coronary arteries during contraction Myogenic control: - NO produce by sheer stress on the vessles **** Therefore, symp activation of heart results in overall coronary vasodilation response and increased coronary flow due to increased metabolic activity (increased HR, contractility) and myogenic activity (increased NO prodcution) despite direct vasoconstrictor effects of symp activation on the coronaries

Stretch receptors in the renal afferent arteriole play a role in the

long term regulation of blood pressure * these control the release of renin: when arteriolar pressure increases the renin secretion is decreased and vice versa

Which type of muscle decresed th length of the GI tube

longitudinal muscle - decreases length, reduces resistance to flow - when the muscle contracts it pulls the tube inward to a shorter length

What occurs if somone who lacks a gallbladder consumes a particularly lipid-rich meal?

loss of the concentrated bile secretion for the gallbladder can result in inadequate lipid digestion and absorption - this can lead to a degree of steatorrhea, lipid in the stools, so such patients are often advised to adopt a diet relatively low in lipids

Cachexia

loss of weight and muscle atrophy due to an underlying medical conditon

Intestinal stenosis

lumen of intestines narrowed fue to INCOMPLETE recanalization

Glycolipids are generally synthesized in the

lumen of the golgi and sent ONLY to the outer leaflet of the plasma membrane or they stay in the lumen - Glycocalyx= a carbohydrate-rich layer extending from the outer leaflet of the bilayer- glycolipids can form an extensive carb layer on outer leaflet of the bilayer- generated by glycolipids and glycoproteins Ex of Glycosphingolipids: - Galactocerebroside: a marker for oligodendrocytes in brain (has sugar residue attached to ceramide via O-glycosidic bond in its structure) - Galactocerebroside-3-sulfate: a sulfated version of galactocerebroside- the sulfate renders it negatively charged - Ganglioside GM2: special glycolipids have one or more special sugar residues called N-Acetylneuramic acid (usually in a branched structure)

In a CT scan the patient is

lying supine - You are viewing the pt from the foot of the bed looking into his body - Right side of pts body is your left, pts left is your right

Essential AA and fatty acids are considered

macro-nutrients - they are NOT vitamins nor minerals

ApoI and ApoII are

major structural proteins of HDL, also in chylomicrons - Apo A-I activates LCAT (Lecithin: Cholesterol Acyl Transferase, needed to esteridy cholesterol extracellularly)

What are some sources of VitC (Ascorbate)?

many fresh fruits and veggies: citrus, potato, broccoli, bell pepper, strawberries etc. Defficiency: Scurvy Sxs: - red bleeding dots (petechiae), purpuric rash, or bruises (ecchymosis) - sore and spongy gums - loose teeth - fragile vessels - swollen joints - microcytic anemia * Sailors called "Scurvy crew" * British sailors called "limeys" - impairment of collagen syn. bc of the proline hydroxylase accounts for the prominent CT abnormalities in Scurvy * the Vit-C transporter in the intestine is saturable and can only absorb 1-2g of ascorbate/day- thus megadoses are incompletely absorbed

The coordination (integration) center (AKA the Nucleus Tractus Solitarious (NTS) is located in the

medulla of the brain stem, compares continuous afferent information from baroreceptors to the normal value or "set point", then activates processes to return conditions to normal if any deviation from the normal value occurs

Small intestinal motility is required for

mixing of chyme with digestive enzymes, exposure of digested contents with intestinal wall - segmentation contractions facilitate mixing, digestion, and absorption - gradually moves materials towards large intestine via peristalsis

Stable Artherosclerotic Plaque (fibrous cap atheroma) -->

moderate/severe lumen narrowing --> chronic ischemia --> sclerosis and atrophy

assessment

monitoring health and diagnosing and investigating illness

FA with only one DB

mono-unsaturated (ex. Oleic acid) - more fluid than saturated FAs, but less so than poly-unsaturated FAs two or more DB are poly-unsaturated (like the essential AA Linoleic and Linolenic acid, omega-6, omega-3 respectivly, * remember these are essential bc we cannot make them in our bodies- need them from diet) - more fluid than the others- depending on the degree (how many DB) and their placement in the hydrocrabon chains) ----- - saturated FAs (no double bonds)- ex. palmitate: these are the least fluid (fat with high % of unsaturated fat is more solid and less healthy - trans fatty acidsL made from chemical hydrogenation of poly-unsaturated oil to alter their physical properties (most DB in nature are cis- so trans fatty acids in high amounts are processed into TAGs and membrane lipids along with normal fatty acids- although they are unsaturated their structure makes them packk more like saturated hydrocardons and have similar deleterious health effects

Sources of VitB1, Thiamine Include:

most foods, including yeast, lean pork, legume seeds Deficiencies: Beriberi: - can occur when polished rice is principal dietary component - mild: GI complaints, weakness, burning feet sensation - severe: peripheral neuropathy, mental abnormality, ataxia also classified as: Dry (neurological deficits) or Wet (edema due to cardiac dysfunction) Wernicke-Korsakoff Syndrome: - when combined with excess alcohol consumption, decreased thiamine absorption for gut- this is usually combned with poor diet - alcoholism results in reduced ability to transport, metabolize and store B1 and may be associated with poorer nutrition resulting in decreased intake - reduced storage due to impaired liver fx., reduced usage due to lowered magnesium uptake which is also a cofactor in thiamine utilizing enzymes Maple Syrup Urine Disease Some complications of Diabetes are also thought to be a result of thiamine deficieny **NOTE: the NS is more sensitive to Thiamine deficiency bc of its dependence on oxidative glucose metabolism

Upon consumption of any nutrients, ____ secretion stops, it is cleared quickly from the blood, and the regular feeding-type pattern of intestinal motility replaces the MMC

motilin

Lipase digestion of dietary fats begins in the

mouth with salivary lipase then acid lipase - only 10% of adult diet fat digested - >90% of milk fat digested (infant diet) ** Pancreatic lipase with its obligate helper, colipase, create fatty acids and monoglycerides - fatty acids and monoglycerides are dissolved out of fat droplets into micelles with action of bile salts - Most monoglycerides are taken into the enterocyte using a fatty acid transporter, FAT - Some monoglycerides are leached out of micelles into the membrane of enterocytes Inside the enterocytes: - TAGs are reformed - TAGs and lipoproteins are packaged into chylomicrons in the goli apparatus - Chylomicrons are extruded into a lacteal (lymph capillary) - Fatty acids 14-18 carbons are re-esterified into TAGs then packaged into chylomicrons and sent via lymphatic system into circulation - Small to medium chain FAs are more soluble and go directly to liver for use - Clinically important: synthetic/high energy content diets contain short chain fatty acids

Mechanical digestion begins in the

mouth: with teeth, tongue, and gums and continues in the stomach with gastric motility - by the time material exit the stomach most mechanical digestion is over - intestinal motility produces the final mechanical digestion of chyme pieces into separate molecules *** mechanical digestions does most of digestions ** churns particles in the stomach

The wall of the stomach consists of the usual 4 layers present in other parts of the GI which are

mucosa, submucosa, muscularis externae, adventitia/serosa *NOTE: longitudinal folds known as gastric rugae are present on the luminal surface of the stomach

The Gastric Mucosal Barrier is secreted by

mucous neck cells in pit, and by surface epithelial cells - req. mucins and bicarbonate (make pH~7) - viscous mucous gel slows flow of acids near surface (it is rich in bicarbonate as well) - bicarbonate neutralizes acid near the apical surface *** Bottom Line: Protected gastric epithelial cells - Mucins are digested in the neutralization zone, so mucus must be replaced continuously NOTE: NSAIDs stop secretion of mucous- contributing to peptic ulcers

Cerebral congestion/edema can lead to

non-speciifc mental dysfunction with confusion in heart failure

Apo-D function

not fully known, but thought to associate with LCAT and link HDL and LDL during transfer of apolipoteins

Excitatory neurons (GLUTAMATE) from NTS also project onto the cardioinhibitory center which consists of

nucleus ambiguus and dorsal motor nucleus of the vagus - stimulation of the cardioinhibitory center by NTS increaseas vagal innervation of the heart which will also act to reduce heart rate and via decreasing cellule cAMP levels also reduce phosphorlyation status of PKA tagets like L-type Ca channel, Ryr, TnI and phospholamban * therefore an increase in baroreceptor discharge via these mechansms leads to vasodilation, venodilation, a decreas in BP, HR, and CO --> this will then REDUCE baroreceptor discharge

Cardiovascular disease is the

number 1 cause of death globally - more ppl die annually from CVDs that from any other cause - 17.7 million ppl died from CVDs in 2015 (31% of all global deaths) - 7.4 million were due to coronary heart disease - 6.7 million were due to stroke * over 3/4th of CVD deaths take place in low and middle income countries *** main contributor of major cardiovascular disease in US is hypertension

case fatality rate

number of deaths due to conditon/ total number of cases of a condition

risk=

number of new cases/ population initialy "at risk" to be a case

Vulnerable plaque (thin-cap/atheroma) in progression to IHD -->

occlusive thombosis --> acute and severe ischemia --> chest pain (unstable angina pectoris) --> MI--> post-infarction scar (old MI)

The highest flow rates of new juice take place precisely when the

old juice is being buffered by foods

A "run" is

one or more points on a side of the median A chart of 24-25 data points, req 8-17 runs to assess for special cause variation (p< 0.05 that the data is merely "random" and due to chance"

The Ileocecal sphincter is the junction of the small and large intestine it has a valve-like structure for

one-way flow - like other sphincters it has a positive resting pressure - It is under control of vagus, sympathetic nerves, and the ENS - Distension or irritation of the ileum results in relaxation of the sphincter: materials to pass into cecum - Distension or irritation of the cecum causes contraction of the sphincter: Materials DO NOT normally pass into ileum, so there is normally NO "backflow", it can resist pressures up to 50-60cmH2O * that there is normally at least some backflow is proven by the fact that some bacteria are present in the terminal ileum to convert primary bile acids into secondary bile acids ---- Remember In ileum: pressure and chemical irritation relax sphincter and excit peristalsis & the fluidity of contents promotes emptying In the Cecum: pressure or chemical irritation inhibits peristalsis of ileum and excites sphincter

Chemical digestion which begins in the

oral cavity and continues in the stomach - some pancreatic amylase and some lipases are active after swallowing, for a while - MOST of the chemical digestion in the stomach is for protein using pepsin (optimum pH ~ 3) - on a quantitative basis, most chemical digestion of macromolecules occurs in the duodenum and jejunum *** very little absorption takes place in the stomach * NOTE: collagen is susceptivle to digestive enzymes

The trabeculated part of the right atrium (Pectinate Muscle) is from the

original primitive atrium and the smooth portion is from the right horn of the sinus venosus (smooth portion is known as sinus venarum) ** the junction between the two is demarcated internally be the crista terminalis

The NS is particularly vulnerable to defects in energy metabolism as it relies on

oxidative metabolism of glucose for a constant energy source therefore the vitamins that are used particularly in energy metabolism show neurological symptoms when deficient - Vit B1, 2, 3, 5, 7 (these are Thiamine, Riboflavin, Niacin, Pantothenic Acid, Biotin)

The anal canal is continuous with the rectum at the

pelvic diaphragm where it makes a 90 degree posterior bend known as the anorectal flexure - The anal canal is divided into an upper and lower part by the pectinate line * these upper and lower halves have diff. embryological origin, so they have diff. blood and nerve supply * see embryology lecture (upper half from hindgut, lower half from invagination of proctidium)

When the anterior abdominal wall is reflected to expose the contents of the abdominal cavity, everything that can be seen is covered in

peritoneum

Technically, pancreatic ducts, bilary ducts, and the gallbladder have an ENS, such that

preganglionic vagal efferent signals stimulate the myenteric plexus to activate ACh-secreting ENS motor neurons to induce gallbladder smooth muscle contraction - since the gallbladder lacks a specific submucosal plexus, it is likely that the other plexus handles both epithelial and smooth muscle cell acitivty in this organ

Cholesterol is an amphipathic molecule, like other membrane lipids because of the

presence of a polar hydroxyl group - polar group is oriented to the outside * cholesterol modulates lipid fluidity - gel,like stiff membranes become more fluid - highly fluid membranes become stiffer by addition of cholesterol ===== NOTE: the esterified form of cholesterol (Cholesterol Esters) contains a fatty acid moiety attached to the hydroxyl - esterification makes cholesterol more hydrophobis - it is carried this way often in lipoprotein particles * cholesterol can also be stored intracellularly as esters

Sources of VitB3, Niacin

present in unrefined grains, milk, lean meat, and liver Niacin deficiency ex: Pellagra: - 4 Ds**: Dermatitits, Diarrhea, Dementia, Death - Acute symptoms resemble sunburn and sun-sensitivity - was common in the US and southern Europe in the early 20th century, now rare except in poverty stricken regions - is poorly absorbed from maize, unless maize is treated * Niacin can be used to treat hyperlipidemia: niacin inhibits hepatocyte synthesis of TAGs by slowing the release of fatty acids from adipose tissue- this results in a decreased secretion of VLDL and LDL particles. Niacin increases HDL, which augments reverse cholesterol transport- this was recently changed to being a treatment recommended only under certain circumstances due to side effects of high niacin doses NOTE: absorption of Niacin is improved by slaking corn with lye, a process called nictamalization (it is used to make masa flour for tortillas)

Bloop pressure always refers to the difference in

pressure between two points

As fluid is secreted into a hollow tube, the ___ goes up in the tube

pressure goes up - creating a pressure gradient between deep part of gastric pit and the main lumen of the stomach - this drives water out into the main cavity, and all the solutes with it

Development of heart failure in HT pateints is most likely due to

pressure overload

Migrating Motor Complex (AKA migrating myoelectric complex) is known for

preventing plugs and getting them defecated ex. kid swallowing a coin

Levels of disease prevention

primordial: prevent risk factors, borad changes in social environment primary: prevent disease before it starts, reduce risk factors seconadr: early detection and treatment for at risk, stop or slow progression of disease tertiary: manage those already with disease, prevent further complication, improve quality of life

Chronic LES (lower esophageal sphincter) insufficiency leads to

prolnged reflux and acid-induced erosion of esophageal muscosa, heartburn, and eventually gastroesophageal reflux disease (GERD) * during the time that the LES is relaxes, acid contents enters the esophagus- notice that the pH falls and may take several minutes to recover - a number of chemical agents ex: certain spices, alcohol, etc. can reduce the esophageal barrier function as well a prolong the duration of the transient relaxation of the LES and lead to irritation * heart burn= burning sensation caused by acid regurgitation into the esophagus

Vitamin B7, Biotin or Vit H (no longer used) serves as a

prosthetic group for many ATP-dependent carboxylases (participates in carboxylate reactions) ex: pyruvate carboxylase (converts pyruvate to OAA) - covalently bound through a lysl residue amide bone

Recus sheath is a fibrous sheath (AKA aponeurosis) which functions to

protect support of abdominal organs, provides maximal compression and it encloses: - rectus abdominis - epigastric vessels - anterior rami of spinal nerve T7-T12 (innervate the anterior abd wall muscles) * it is compose of the aponeuroses of the 3 flat muscles: external oblique, internal oblique, and transversus abdominosis as they converge in the midline to form the linea alba - formation of the sheath varies according to location

Normally in Amino Acid Transport- Digestion reduces

proteins to AAs, dipeptides, and tripeptides - microflora of the gut can further digest larger peptides - transporters move classes, not specific substrates - system is redundant DISEASES: HARTNUPS: a deficiency or loss of the neutral AA transporter - only causes malabsorption in poor nutrition states such as drug abuse, prologned illness, kwashikor, marasmus or cachexia - lack of uptake of tryptophan causes PELLAGRA like dermatitis, decrease serotonin, decreased melatonin and decreased Niacin KWASHIORKOR: lack of protein in the diet - the lack of AA results in inability to produce albumin (lowering of blood albumin causes increasing edema which also progresses to an enlarged abdomen. - most common in famines where protein acess is limites - Edema and fatty livers (enlarged abdomen) - Dermatitis like PELLAGRA MARASMUS: lack of energy intake (famine and starvation) - due to an EXTREME lack of calories in the diet

Rapunzel syndrome

rare condition in which hairs that a person has eaten become trapped in their stomach

Capillaries

receive blood from metarterioles - site of exchange of gases and nutrients between the blood and extravascular tissue - diameter of 4-10micrometers allows for single file of RBCs to pass through - Tunica intima consists of endothelium and basal lamina only ONLY has a tunica intima - NO tunica media or tunica adventitia

Vit B2, Riboflavin serves as a

redox cofactor in many enzymes in the form of FMN, FAD, e.g. NADH dehydrogenase and succinate dehydrogenase - typically remains tightly bound to the enzyme - absorption is through energy dependent transport in the upper small intestine * FAD usually acts as a prosthetic group and remains tightly bound

Development of heart failure in pt with MI can be due to

reduce contractility and impaired relaxation (bc heart muscle fibers died and healed with fibrosis)

At very high heart rates SV may begin to

reduce due to reduced filling time During exercise: Elevation in SV comes from: 1. increased venous return (from increased preload) 2. increased contractility (causes reduced ESV) Elevation in HR comes from: 1. increased SNS activity 2. decreased PNS activity *** higher cardiac outputs (above 15L/min) is achieved by increases in HR not stroke volume

Liver failure of kidney disease-->

reduce plasma protein production --> decreased colloid osmotic pressure --> decreased reabsorption --> peripheral edema Several causes of this: 1. nephrotic syndrome (kidney disease) causes the loss of proteins in the urine 2. liver failure causes the liver to produce fewer proteins than usual 3. malnutrition prevents proteins from being produced due to lack of AAs in the diet *** all of these result in reduce plasma colloid osmotic pressure which reduces reabsorption of fluid from the interstitial space to the capillaries and may lead to peripheral edema

Lymphatic Obstruction (surgery, radiation, cancer, and enlarged lymph nodes) -->

reduced flow from interstitial tissue to lymph system --> increasd interstitial hydrostatic pressure (fluid accumulation in interstitium) --> increased reabsorption but exceeds capacity of capillaries to reabsorb --> peripheral edema

Since few transporters are available for uptake of proteins in the intestine. Uptake as smaller peptides..

reduces the number of transporters needed - NOT all AAs have transporters so they must be taken up as dipeptides or tripeptides ** Most AA transports are Na+ symporters (in SI there is one on apical membrane that transports Alanine Serine and Cysteine ONLY) *** A B0 (genetic AA transporter) on apical membrane transports neutral AA) *** Transporters on basolateral surface of enterocytes are usually symporters NOTE that in the kidney the same transporters allow for reuptake of AAs from the filtrate - 6 out of 10 diseases caused by transport defects are due to malabsorption of AAs in the small intestine brush border ------ NOTE: - concerted efforts of many peptidases result in primarily tri- and di-peptides. AAs may also be produced - very few transporters exist for non-hormonal protein uptake - pepitde transporters are usually symporter using Na+ as the ion - B+: transport cationic AA - B-: transport anionic (acidic AA)

Electrical stimulation of the carotid sinus nerve mimics an increase in baroreceptor discharge i.e. mimics an increase in arterial pressure- this results in

reflex hypotension and bradycardia as S discharde is inhibited and P increases

cardiac index (CI)

relates cardiac performance to the size of the individual CI= CO/ body surface area (BSA) - the normal range of cardiac index is 2.6-4.2L/min per square meter ** is the CI falls below 1.8L/min, the patient may be in cadiogenic shock

Retroperitoneal abd organs are

relatively fixed Defined as lying behind the peritoneal cavity with ONLY PART of its surgace covered by peritoneum can have Primary retroperitoneal structures: are retroperitoneal from the START of their development - suprarenal (adrenal) glands - ureters - kidneys - aorta and IVC - esophagus - rectum: proximal 1/3rd Secondary retroperitoneal: were once suspenced within the abd cavity by mesentery but migrated posteriorly to end up behind the periotoneum durine development (intra--> retoperitoneal after development) - Duodenum: 2nd, 3rd, and 4th parts - Pancreas: head, neck and body - Ascending colon - Descending colon ** SAD PUCKER - for retroperitoneal organs

Cranio-caudal folding

repositons the heart tubes into the presumptive thoracic region - herat tube is positioned ventral to foregut and caudal to oral cavity and brain

Central Venous Pressure (CVP)

represents the avg blood pressure within the venous compartment CVP is the pressure in the thoracic vena cava near the RA which drives venous return - changes in CVP can result from change in blood volume within the thoracic veins and also by changes in compliance of these vessels (Cv) Change in CVP= Change in volume/ Cv - an increase in BV will increase CVP - an increase in compliance will reduce CVP * this means that an increase in venous tone (aka decreased compliance or increased resistance) will shift the volume pressure curve downwards- therefore at any given volume, this will lead to an increase in central venous pressure with concomitant decrease in venous volume in the capacitance vessels as blood is displaced towards the heart ---------- CVP is a major determinant of filling pressure and therefore preload of the RV, which reg. stroke volume through the Frank starling mechanism

The most exposed of all mucosal surfaces is the

respiratory tract * we constantly breathe in non-sterile air * respiratory tract infections are the most common causes of disease in humans (85.6% infections/100 persons/yr) (54% of all acute conditions, excluding injuries)

Elite athletes will have a lower

resting HR but an increased: - max HR - resting SV (bc greater EDV filling- increases ejection fraction) - exercising SV - maximum CO - L ventricular mass *** resting cardiac output will stay the same ** max HR is estimated by subtracting a persons age from 220

The ileum is mostly found in what abd. quadrant

right lower quadrant (RLQ) - accounts for the distal 3/5ths (3.5m) - intraperitoneal - absorbs any products of digestion that the jejunum missed * has clinically significant epithelial lininig: Peyers Patches --- stomach --> duodenum --> jejunum--> ileum

Primitive atrium gives rise to the

rough protion of the RA and LA

In females the lower gubernaculum becomes the

round ligament of the uterus

Vulnerable artherosclerotic plaque is characterized by

rupture of thin fibrous cap

Alpha-amylase is secreted by the

salivary gland and pancreas (acinar cells) - salivary gland for release of sugar by direct absorption to start cephalic phase - pancreas is most active secretion ** amylase is the only glycosidase that is NOT membrane bound enzyme on the enterocyte directly

In reality all of the intestinal crypt cells are secreting more ____ than ___

secreting more Cl- and Na+ than bicarbonate - which drive about 1L of water/day into SI - the newly secrted bicarb acts as a buffer to neutralize stomach acid and create a weakly alkaline environement in the duodenal and jejunal lumen in which digestive enzymes can function at their peak function However, the relative contribution of crypt cells must be added to that of pancreatic ducts and bile ducts; each only contributes a part to this pH modificiton - the pH of the intestinal lumen rises to close to 8.0, which is close to the pH optimum of many pancreatic digestive enzymes

List the flow of sperm out the seminiferous tubules (which produce spermatazoa)

seminiferous tubules --> straight tubule --> rete testis --> efferent ductules --> head of epididymis --> (through epididymis) --> tail of epididiymis --> continuous with ductus deferenes --> expelled out through penis

Vascular resistance of vessels arranged in

series - Total resistance is sum of each individual resistance Rtotal= R1+ R2 + R3..... *** radius of a given vessel is primiary determinant of resistance to flow, however how vessels are arranges, that is in series or parallel influences the total resistance

Metabolome

shared metabolism between the microbiota and the human host Its functions include: - Digests complex carbs via fermentation (SCFA (C1-C5) provide 70-90% of energy to colonic enterocytes) (SCFA are ligands for GPCR1 and GPCR43 which upregulate histone deacytlases which results in episomal regulation of gene expression-- this increases cellular growth and turns anti-inflammatory genes on) - produce essential vitamins - produce branch chain AAs - regulate immune system - regulates both enteric and CNS *** By the time food gets to colon most of the absorbed nutrients are gone- only thing remaining is things we cant digest- and this is where our microbiota come in with the SCFA ------ The pre-digestion of foods by microorganisms leads to productions of important molecules - the blood supply of the large intestine is insufficient to feed the enterocyttes adequately so many of the needed nutrients are taken from the microorganisms instead - majority of calories for large intestinal enterocytes are from SCFA - most AAs taken up of general use occurs in the duodenum and jejunum. In the ileum and large intestine the AA transport is to support enterocytes directly

Inflammation of the PARIETAL peritoneum causes

sharp, well-localized pain and tenderness on palpation

Usually air flow from the pharynx--> trachea--> lungs but when it is time to swallow the breathing is

shut off

Bile duct is lined by

simple cuboidal epithelium

The main pancreatic ducts lumen is lined by a

single layer of cuboidal cells - the thickness of the collagenous duct wall is impressive and is probably accentuated because the lumen is empty and collapsed (see slide 45 in glands)

Lipoproteins differ in

size, density, and charge (largest to smallest: chylomicrons> VLDL>LDL>HDL) - they can be separated on the basis of these - MOST COMMON in scientific labs is separation by centrifugations, which works both through density and size differences - Lipoproteins can also be separated by electrophoresis on basis of size and charge at same time (chlyomicron at top, LDL(beta-lipoprotein), VLDL(pre-betalipoprotein), then HDL(alpha-lipoprotein) closest to anode (+)) - Clinical lab tests rely on measurements of TG, total cholesterol, and HDL cholesterol. LDL cholesterol is computes (using Friedwald Equation- this req. that pt be fasted and that TAGs are within a certain limit, having recently eaten will perturb TAG levels and throw off the estimate--> this is an important clinical measurement to determine if someone is at risk for acquiring artherosclerosis) - Newer methods are available, but not yet in common use

In the middle third of the esophagus you find a combination of

skeletal muscle fibers and multi-unit smooth muscle fibers that are controlled by motor units just like skeletal muscle - within this region the unitary smooth muscle transition in such that by the last 1/3 of the esophagus the familiar ENS with its 2 plexuses and 2 layers of smooth muscle is fully established and the swallowing centers direct control over muscle contraction ends *** the skeletal muscle fibers have both circular and longitudinal orientation and as such can perform peristalsis

Interstitial Cells of Cajal (ICC's) set the rate of

slow waves in different regions: - slower rate in stomach (3-4 waves/min) - faster rate in small intestine (ex. 10-12 waves/min in duodenum) - slower rate again in the colon (3-7 waves/min) ICC's are found in the stomachs "pacemaker region" and within the walls of the SI and colon - all locations in which phasic smooth m. contraction begins in their respective sections of the stomach and intestinal tract * ICCs are specialized group of networked cells that are functionally part of the myenteric plexus for the relevant regions of the gut tube that have them (stomach to colon) (since they are the final connection point betweeen ENS neurons and the actual smooth m. cells) - they help transmit info from enteric neurons to smooth m. cells NOTE: Slow waves actually begin with the ICC cell network and are passed to the actual single-unit smooth m. through calcium channels in a coordinated fashion

As you progress more inferiorly on a CT scan of the upper abd the __ become more visible

spleen - at about the umbilicus region one can see the pancreas posterior to the stomach

Splenic artery travels in the ______ with the tail of the pancreas

splenorenal ligament

natural history of ischemic heart disease with a stable coronary plaque

stable plaque (fibfrous cap/atheroma) --> chronic moderate/sever luminal narrowing --> chest pain/ stable angina pectoris

The membrane potential in SA nodal cells is NEVER

stable, but changes continuousy (autmoaticity in the heart) - cells that display these characteristic have capacity to act as PACEMAKER CELLS and generate APs which can be conducted throughout a tissue * In the case of the heart these AP, spread rapidaly AWAY from the SA node and innervate the atrial and ventricular tissue

VitD, cholecalciferol is a group of

sterols, that can be synthesized in the skin - active molecule: calcitriol (1,25- dihydrocholecalciferol) Metabolism: - from diet as ergocalciferol (one hydroxyl) which is then converted to cholecalciferol - from conversion of sunlight in the skin (start with 7-dehydrocholesterol--> cholecalciferol) VitD maintains plasma Ca2+ via: - increase intestinal absorption by increasing transcription in the intestine - minimize kidney loss through resorption - demineralization of bone ** Concentrations of calcitriol are regulated by the liver and kidney - the precursor, calcidiol is mobilized in the liver and converted to calcitriol in the kidney by adding hydroxyl groups * this is a highly regulated process that depends on plasma calcium and phosphate concentrations and on parathyroid hormone

As compliance of a vessel decreases its

stiffness increases - stiffness (or elastance) is reciproval of compliance: change in pressure/ change in volume ** aging would decrease elastin which would increase compliance BUTTTT agiing overall increases vessel resistance so this is why as you age you vessels bcome less compliant

In general, ECL cell secretion of histamine

stimulates parietal cells (very potent effect)

BOTH the indirect and direct inguinal hernias emerge from the

superficial inguinal ring

Moving from supine to standing

supine- little variation in arterial or venous pressure throughout the body upright- add effects of gravity onto BP **** BP in vessels above the heart reduced **** BP in vessels BELOW the heart is increases - BP changes by 0.78mmHg for every cm above/below the heart- hence why blood pressure is measured at the level of the heart *** in periphery, bc of effects of gravity this makes edema more likely if the mechanisms supporting venous return are compromised ------- on standing from a supine position, cerebral BP is likely to fall rapidly from a value of apprx. 90mmHg to apprc 60 mmHg unless mechanisms are invoked to increase MAP

Only definitive treatment for acute appendicitis is

surgical removal, performed emergently

In females the upper gubernaculum becomes the

suspensory ligament of the ovary

Blood volume distribution- most of the blood is in the

systemic circulation at rest (~80%), BUT of this volume only ~14% is in the high pressure arterials - in systemic circulation the low pressure veins contain the majority of the blood (~60%) and serve as reservoia that be utilized during time of low blood volume or pressure - only 5% of blood is contained in capillaries at rest *** effects of gravity contribute to the pooling of blood in the lower extremities

Pulse pressure=

systolic BP- diastolic BP

Long Chain fatty acids (greater than C12) are

taken into enterocytes by the FA transporter, FAT - reassembled into di- and tri- glycerides in enterocytes - FA lengths 14-18 are put into chylomicrons in golgi after re-esterification (chylomicrons put into chylomicrons and eventually make their way into the liver)

Marginal Artery of Drummond

term used to describe the arteries supplying the midgut and hindgut when collectively they form a continuous circle along the inner border of the large colon ** During development, the middle colic artery may NOT meet with the L colic artery and this is why the commonest area of colonic ischemia is at the splenic flexure --> in this case its known as Sudecks point *** Clinically the anastomosis of the superior and inferior mesenteric arteries provides COLLATERAL flow in the event of occlusion of significant stenosis

cobalamin (vitamin B12) is absorbed in the

terminal ileum - VitB12 is required for proper blood synthesis - Intrinsic factor (secreted by parietal cells) protects this peptide from digestion - Once past the digestive enzymes in the terminal ileum, the complex (IF-B12 receptor complex) is absorbed through endocytosis - VitB12 enters portal blood, intrinsic factor is degraded *** So intrinsic factor protects cobalamin (VItB12 in the small intestine) NOTE: there is a second protein (haptocorrin) which is secreted by salivary and gastric glands that also protects cobalamin, BUT it never survives all the way to the terminal ileum so it is NOT tested on the USMLE - you are not responsible for this its just FYI

If the membrane was ONLY permeable to Na+ then the membrane potential would equal or be very close to

the Nernst potential for sodium (+60mV) - If only permeable to K+: membrane potential would be Nerst potential for K+ (-90mv) - Similarly for Ca2+, membrane potential would be the Nernst potential for Ca2+ (+130mV) -------------- If membrane permeable to BOTH Na+ and K+, then depending on relative permeability to the two ions you could achieve any voltage between -90mV and +60mV --> this is what happens during an AP, the relative permeability of the membrane to ions changes generating changes in membrane potential * if the concentrations of ions change (i.e. magnitude of the conc. gradient, then you would need to recalculate the Nersnt potential for the new conditions and therefore membrane potential would also change ------ REMEMBER - Major EXTRAcellular cation= Na+ (Na+ wants to come in the cell down its concentraton gradient and following the electrochemical gradient (neg on inside, pos. outside where Na+ abundantly found) - Major INTRAcellular cation= K+ (wants to leave cell down its concentration gradient) - Ca2+ has a major diff. of conc with it being way more abundant on outside, Ca2+ wants to flow into cell with its concentration gradient

Irritation/pain of the diaphragm (liver, gallbladder or duodenum) can be reffered to

the Right Shoulder

The arcuate line marks the point at which

the aponeuroses of ALL 3 lateral abdominal muscles pass anterior to the rectus abdominis muscle * at this level, the internal aspect of the rectus abdominis muscle is in direct contact with the transversalis fascia

Intercostal Veins accompany

the arteria and nerves - the lie immediately & superiorly along the costal grooves (VAN) - 11 posterior on each side (R&L) * MOST posterior intercostal veins (4-11) drain into the azygos/hemiazygos system and then into the SVC--> R. Atrium ------Post intercostl v. --> Azygos --> SVC (on R)---- ----Post intecostal v. --> hemizygos --> Azygos --> SVC (on L) ** ANTERIOR intercostal veins-> drain into the thoracic vein

Etiology

the cause, set of causes, or manner of causation of a disease or condition

The lumen of the esophagus has many folds that are visible when

the esophagus is empty, the esophagus stretches and the folds unfold to accomodate swallowed food

Proton-Pump Inhibitors (PPIs) work by blocking

the final step in acid production, therefore they effectively suppress stimulated acid production, regardless of the physiological stimulus (90-95% acid suppresion) Thesse include: - Omeprazole - Esomeprazole MOA: - Covalently bind with irreversible inhibition of the H+/K+ ATPse PPIs are lipophilic weak bases (pka4-5) and after intestinal absorption diffuse reading across lipid membranes into the acidified compartment of the parietal cell canaliculus - The prodrug rapidly becomes protonated and is concentrated more than 1000-fold by Henderson-Hasselbalch trapping - The activated drug forms a covalent bond with the H+/K+ ATPase - Acid secretion resumes only after new pump molecules are synthesized and inserted into the luminal membrane (24-48hrs)

Cardiogenic Shock (or heart failure)

the inability of the ventricles to pump blood at sufficient volume, usually due to impaired cardiac function (i.e. myocardial infarcation or heart fialure) Characterized by two diff. criteria: 1. Left Heart failure vs. Right heart failure 2. Systolic Dysfunction vs. Diastolic Dysfunction

Hyperplasia

the increase in cells (enlargement) of an organ or tissue due to increased proliferation of its (differentiated or progenitor) cells - increased cells, increased tissue - increase in size due to increase in numbers

The femoral artery and vein can be found posterior to

the inguinal canal which travels obliquely and inferomedially and runs for about 4cm

Wherever the circular smooth muscle is contracting in the gut wall,

the longitudinal muscle in same section will be relaxing - and wherever longitudinal smooth m. is contracting, circular muscle is relaxing ** the combo of contracting circular muscle and extra-relaxed longitudinal muscle- increases pressure and resistance at the contraction site ** in contrast: combo of greatly relaxed circular muscle with contracting longitudinal muscle: reduces resistance and pressure at that location *** when one section of tube has net pressure increase and a nearby section of tube has net pressure decrease AND reduced resistance- materials will move from the high pressure to the low pressure area ** remember - contraction is with ACh or Substance P - relaxation is with VIP or NO

Intestinal Atresia

the lumen is occluded (completely blocked) as a result of FAILED racanalization. Most occur in the duodenum ** so basically it closes in development and does not open again like it should NOTE: Atresia or stensosis of the gut would cause a considerable backup in the gut leading to excessive GI distension and excessive vomiting in newborns ** Duplication of intestines can occur with abnormal recanalization

Pathogenesis

the manner of development of a disease "mechanism/route by which disease comes about"

alpha1-adrenergic receptors are

the predominant alpha-receptor on vascular smooth muscle - activation of these by circulating catecholamines will lead to constriction of both arteries and veins, however, the vasoconstrictor effect is more pronouced ina rterial resistance vessels - constriction of the resistance vessels (small arteries and arterioles) increases TPR, whereas constriction of the venous capacitance vessels increases venous pressure and increased venous return

Pathology

the science (study) of the causes and effects of disease

If for whatever reason other digestible nutrients (ex. lactose secondary to lack of functioning lactase) appear in the colon

these nutrients can cause an inappropriate overgrowth of bacteria beyond that required for proper stool formation - If excess TAG show up from lack of bile, etc.the bacteria will metabolize some of those too, again producing metabolic waste products that act as osmotic components, producing a fatty diarrhea (steatorrhea)

Why can CCBs be used to treat Arrhythmias

they effect AV and SA nodes Verapamil and Diltiazem used clinically (Class 4 antiarrhythmics) - decrease HR - decrease excitability of SA node (reduced automaticity) - prolongs AV node conduction (increasee PR interval) Use: Supraventricular including Atrial FIbrillation and flutter - increase in AV refractoriness: inhibits re-entrance - slowing of AV conduction provides "rate" control in Afib/flutter ** DHPs are preferential to VSM, NOT useful for arrhythmia

Sibson's Fascia

thickened endothoracic fascia above the 1st rid to C7 transverse process (covers the apex of the lung, which is prone to injuries)

Vulnerable plaque (thin cap atheroma)-->

thin cap rupture --> activation of clotting cascade--> occlusive thrombosis --> acute ischemia--> infarction

Wedge pressure

to determine pressure in R heart structures you can catheterize them directly - it is more challenging to direclty catheterize the L heart structures bc they are under high pressure ** Wedge pressure can be used to apprc the LA pressure Ex. LAP can be estimated via wedge pressure in pulmonary artery (normal wedge pressure= 8-12mmHg) ** using pulmonary artery ballon catheters (SWAN-GANZ) ** Can diagnose Mitral Stenosis or CHF- both would lead to increase LAP or wedge pressure ------------ Wedge pressure can be used to: - facilitate measurement of pulmonary vascular resistance - to diagnose mitral stenosis and CHF: both lead to increase LAP or wedge pressure; the former bc of increased resistance to flow via the stenotic mitral valve and in the latter bc of decreased LV contractility/function for ex as a result of LVHF

Vitamin E, tocopherol includes a mixture of

tocopherols (8 naturally occurring): alpha-tocopherol is MOST active Principal function is an ANTIOXIDANT for non-enzymatic oxidation - prevents non-enzymatic oxidation of cellular components by free radicals - acts as a free radical scavenger (prevents oxidation of LDL and preoxidation of poly-unsaturated fatty acids by oxygen and free radicals) * Oxidized Vit E can be regenerated by Vit C * VitE is not generally recommended for prevention of chronic diseases such as CV disease or cancer, VitE supplementation has been disappointing in clinical trials with little or no observed benefit It is distributed from small intestine in chylomicrons ----- Generally there is NO toxicity with Vit E, even with as a high as 300 mg/day dose but there is an upper limit set of 1000mg/d RDA for VitE is 15mg/d - newborns, especially premature infants and low birth weight infants may need supplements (breast milk and formula have VitE, so supplementation is not required under normal circumstances) - if there is adult deficiency, it is usually associated with defective lipid absorption or transport

prevalence=

total number of cases/ number of population "at risk" to be a case

The Greater Omentum connects the

transverse colon to GREATER curvature of stomach - hangs down and is able to move within the peritoneal cavity " abdominal policeman"- can wrap around organs to localize inflammation and prevent peritoneal adhesions

In myocytes Ca2+ binds to

troponin and disinhibits troponins inhibition of contractile apparatus

T or F: In between Parietal Cells the junctions are relatively tight, such that acid doesnt commonly leak back into the extracellular fluid bathing cells on their basolateral sides

true

T or F: Fat has a higher energy content than proteins and carbs (9 cal/g) and is a MAJOR energy source

true!

T or F: always start with the LEAST invasive imaging technisue (i.e. ultrasound)

true!

Processus vaginalis becomes the

tunica vaginalis in males ** tunica vaginalis is the serous sheath of the testis and epididymis

Best imaging to see the liver

ultra sound - right HV, middle HV, and left HV are seen clearly

main contributors to rise in HTN=

unhealthy diets, inactivity and consumption of alcohol and tobacoo Stage 1 HTN: 130-139/80-89 Stage 2 HTN: >/= 140/ >/= 90 mmHg

Fructose uses a

uniport, GLUT-5, absorption is only half as fast

Describe the junction of the esophagus and stomach

unlike the junction with other organs in the GI tract there is NO morphological thickening of the inner circular layer into a sphincter at the junction of esophagus and stomach- instead there is an area of increased muscle tone, a so-called "physiological" sphincter which prevents reflux of stomach contents

In adipose, Insulin _____ LPL to facilitate fat storage

upregulates! - fatty acids are moved into the adipocytes and remade into TAGs

Apo-E mediates

uptake of chylomicron remnants and IDL by liver * delivers by HDL to VLDL and chylomicrons * also in IDL but NOT LDL - it serves as a ligand for chylomicron remnant uptake by the liver

If the male urethra tears (ruptures)

urine can leak out into the loose CT around the scrotum, penis and anterior abd wall - fluid may extravasate (escape) into the perineal area where it can accumulate deep to Colles' fascia (sup. fascia of the perineum) and spread under Dartos fascia (sup. fascia of penis and dartos fascia of scrotum) and Scarpas Fascia (membranous layer of subcutaneous tissue in the abd.) * bc of line of fusion: no fluid will leak into the thigh * Straddle injury: trauma of the perineal area (in males thi sis between the scrotum and anus) caused by a forceful blow with a hard object

CT urogram

uses contrast to view kidneys, ureters, and bladder

The majority of the liver blood supply is

venous (about 1/4 of typical cardiac output in total) - the liver receives venous blood from all abdominopelvic GI organs (stomach to rectum) and the spleen - hepatocytes can process materials for excretion via bile and/or urine (detoxing) *this describes the splanchnic circulation in terms of the liver - splanchnic circulation= the blood flow to the abd GI organs including stomach, liver, spleen, pancreas, SI and LI

There is only on RAP where the cardiac output equals the

venous return (normal point) - as contractility, blood volume, venous compliance or arteriolar resistance are altered, the intersection point of these two lines will change **** cardiac function curve and vascular function curve plotted together Under nml condition- CO and venous retunr= 5L/min at RAP of ~2mmHg

Majority of blood volume is located on the

venous side in the so-called capacitance vessels

Inflammation --> increased

vessel permeability to proteins --> increased interstitial collid osmotic pressure (proteins in interstitium) --> increased filtration --> peripheral edema bc more fluid is pulled into interstitial space (usually localized) ** inflammation is mediated by chemicals that increase the blood vessel wall permeability, resulting in an exudation (leakage) of plasma proteins and fluid into the tissue

Small intestine is dominated by

villi (surface area reaching up) and crypts (surfaace area reaching down) - villus epithelial cells are generally absorptic (older cells) - villus crypt cells are more secretive (younger cells) ----------------- Large intestine on the other hand is dominated by surface epithelium and crypts- NO VILLI! (since nutrients move so slowly through colon/LI- no villi needed to absorb)

Hematemesis

vomiting of blood that can be similar to coffee grounds

Liver bile has a greater concentration of

water, sodium ions, chloride, bicarbonate --- whereas gallbladder bile has a higher concentration of - potassium ions, calcium ions, bile salts, bilirubin, cholesterol, fatty acids, lecithin

Dextrocardia

when the heart lies on the RIGHT side of thorax instead of left due to abnormal heart looping - this can be an isolated defect BUT is usually accompanied by other severe cardiac anomalies Ex. Single Ventricle ----- If associated with Situs Inversus Totalis ( a condition in which the organs of the chest and abd are arranged in a perfect mirror image reversal of the normal positioning) - most affected individuals can live a normal life without associated symtpoms or disability as the frequency of accompanying cardiac defects is low

Compensated shock

with blood losses of 10-20% of total volume, reflex compensation can usually restore MAP close to normal and maintain adequate vital organ perfusion and oxygenation Normalization of BP is due to: - increase HR, cardiac contractility, and vascular resistance - decreased venous compliance * fluids must be administered or ingested ** even though BP may be normal, CO may remain depressed due to reduced stroke volume ** phase of hypovolemic shock

Jaundice is the

yeloowing of the skin and sclera of the eyes the usually results if BILE is UNABLE to be relesed into the duodenum

Feedback mechanisms work to maintain a mean arterial pressure (MAP) of

~100mmHg * this is accomplished primarily by closely regulating CO and TPR via sympathetic regulation (the body measures pressure on both the arterial and venous sides of systemic circulation) MAP= CO x TPR NOTE: - if flow of blood is inadequat, CO2 builds up and acidosis occurs - if flow is in excess, CO2 is washed away and alkalosis results * this is why blood flow precisely matches the metabolis needs of each vascular bed * vascular beds get what they need (like a town water supply)-a faucet in the sink is analogous to arterioles that control blood supply locally through changes in resistance

Approximately how much small intestinal water absorption occurs/day

~6.5-7L/day (this is quantitatively very important) - still leaves 2L/day presented to colon- and almost all of this is absorbed/reabsorbed here ---- MOST nutrients are absorbed in the small intestine as are most of the fluids supporting the digestion and absorption of these nutrients - both active and passive mechanisms are involved - fluid movement is always coupled with solute movement ---- NOTE: the ingested fluid is only a small amt of the total in the GI lumen because of secretions from salivary glands, gastric pits, intestinal wall, pancreatic acini and ducts, and hepatic bile

In Identifying a Quality Gap one can ask the question

"How are we doing?" Ex. If its suggested the beta blockers be given after an MI but what is the % of hospitals actually doing this? From here: establish a model for improvement - What are we trying to accomplish? - How will we know a change is an improvement? - What change can we make that will result in an improvement? " Act --> Plan --> Study --> Do"

Rib Dislocation

"slipping rib" syndrome - displacement of sternocostal joint (costal cartilage from the sternum) or between the interchondral joints - displaced rib can cause injuries to the underlying structures (neurvascular, diaphragm and liver)

Pulmonary Vascular Resistance (PVR)=

(Mean Pulmonary Arterial Pressure (MPAP)- Pulmonary wedge pressure (PWP))/ CO

The Duodenum is both a Foregut and Midgut Derivative. As the stomach rotates, the duodenum...

(and head of pancreas) are pressed dorsally against the body wall - Dorsal mesoduodenum fuses with peritoneum- therefore the majority of the duodenum and pancreas become retroperitoneal structures

The liver synthesizes

- BILE - Amino Acids - Glucose (gluconeogenesis) - Cholesterol

The liver stores

- Glucose - Iron

"Red flags" in Constipation

- Hematochezia (blood in stool) - Family history of colon cancer - Inflammatory bowel disease (ex. Crohns Disease) - Anemia - Positive fecal occult blood test - Unexplained weight loss >/= 10 pounds - Constipation that is refractory to treatment - New-onset constipation without evidence of potential primary cause

In cancer of the neck and body of the pancreas, a tumor could obstruct

- Hepatic Portal Vein - Inferior Vena Cava

What is found in the Left Lumbar region

- Left kidney - Descending colon - Small intestine

What types of things lead to protection (epithelial integrity)

- Mucus - HCO3- - Prostaglandins - Neuro and paracrines - Blood flow

Carb-related diseases/ disorders include

- Obesity - Diabetes

The liver breaksdown

- TOXINS - Hormones - Drugs - Amonia

Venous System (Three paired veins) in embryo

- Vitelline veins: drain poorly oxygenated blood from yolk sac - Umbilical veins: return OXYGENATED blood from placenta - L/R Common Cardinal Veins: drain poorly oxygenated venous blood from body of embryo

Haustra

- contraction of the teniae coli results in shortening of the intestinal wall - sacculations form as the wall becomes "baggy" and gathered - visible on the external surface - collectively these pouches are called haustra (singular is haustrum)

LDL

- delivery of cholesterol to peripheral tissues - derived from VLDL via IDL - taken up in peripheral tissues and liver

What structures are derived from the midgut?

- duodenum: (distal) 2nd, 3rd, and 4th parts - jejunum - ileum - cecum - appendix - ascending colon - transverse colon: proximal 2/3rd * supplied by the superior mesenteric artery- branches from the abd aorta at the level at L1

Midgut gives rise to

- duodenum: distal 2nd, 3rd, and 4th parts - jejunum - ileum - cecum - appendix - ascending colon - transverse colon: proximal 2/3rds ****** all supplied by superior mesenteric artery - branches from the abd aorta at the level of L1

Wernicke-Korsakoff Syndrome

- occurs with alcohol toxicity and low thiamine intake Acute stage: Wernicke encelopathy - mental derangement, ataxia, paralysis of eye muscles - req. immediate treatment with thiamine injection Chronic stage: Korsakoff Psychosis - severe debilitating anterograde amnesia, damage in the frontal lobes *** pts show a degeneration of an area of the brain known as the mamillary bodies

Chief cells (AKA zymogenic cells/peptic cells)

- only found in gastric glands where they predominate in the lower 1/3 (base) of the gland - triangular shape, basally located nuclei, strongly basophilic - granules visible - produce pepsinogen ( a non-acidic fluid that helps push acidic fluid out of the pit) and a weak lipase (like lingual lipase- not that important) * these are found at the base of the fundus/body of the stomach

Gastrin stimulates

- parietal cells (direct effect) - ECL cells (indirect) - antrum D cells (regulatory) * allow for secretion of gastric acid

Somatostatin inhibits the secretion of gastric acid by inhibiting

- parietal cells (direct effect) - ECL cells (indirect) - antrum G cells (indirect) * indirect means its action is on another cell (ECL, G, D cells) that modify parietal cell secretion

The caloric requirements for average male (70 kg adult weight)

- peaks at 20 - activity increases the caloric need - will vary with size and body type

Considering the Anterolateral Muscles of the Abd Wall as a group they all

- provide support for viscera - can act as acessory muscles of respiration - aid expulsive efforts - the muscles of both sides (R/L) act together in flexion of the trunk - unilateral action produces LATERAL flexion while the obliques can rotate the trunk ----- There are 2 "vertical" anterolateral muscles: - Rectus abdominis (R/L) - Pyramidalis (absent in 20% of people) 3 "flat" anterolateral muscles: - External oblique (most superficial) - Internal oblique - Transversus abdominis (deep) *** there is aponeurosis of the muscles above (white) - aponeurosis= a sheet of pearly white fibrous tissue that takes the place of a tendon in flat muscles having a wide area of attachment (contributes to strength of rectus sheath)

Life-threatening causes of Acute Abdomen

- ruptured abdominal aortic aneurysm - perforative peritonitis from conditions such as actue cholecystitis, acute appendicitis - intestinal obstruction - mesenteric ischemia - ruptured ectopic pregnancy - acute pancreatitis

Describe the 3rd part of the duodenum (aka transverse, inferior, horizontal part):

- secondary retroperitoneal - cross posteriorly under the superior mesenteric artery (and vein) - passes anteriorly over the inferior vena cava - closely related to the uncinate process of the pancreas and the root of the mesentery - lies at the level of L3 and crosses from R to L - longest section of the duodenum - supplied by the superior mesenteric artery

Describe the appendix

- simple columnar epithelium - submucosa filled entirely with both diffuse lymphatic tissue and nodules, all containing plasma cells - largest number of lymphatic nodules per unit area in any region of the GI tract ** so if you see high conc. of lymphoid nodules- tells you youre in appendix - you can also see test tube glands and goblet cells

What is found in the Left Hypochondriac Region

- stomach - liver (tip) - spleen - pancreas (tail) - left kidney - left colic flexure (transverse and descending colon)

VLDL

- transport TAGs and cholesterol - synthesized in the liver - eventually becomes IDL and then LDL

Chylomicrons

- transport dietary TAGs, cholesterol, lipids, fat soluble vitamins from intestine - synthesized in the intestines - highest proportion of TAGs - remnants removed by the liver

What are the structures derived from the hindgut?

- transverse colon: distal 1/3rd - descending colon - sigmoid colon - rectum & anal canal- at the pectinate line * supplied by the inferior mesenteric artery branches from the abd aorta at the level of L3

Hindgut gives rise to

- transverse colon: distal 1/3rds - descending colon - sigmoid colon - rectum and anal canal: above the pectinate line *** all supplied by inferior mesenteric artery - branchs from the abd aorta at the level of L3

Presentation/Symptoms of Acute Cholecystitis

- upper right abd pain - radiates to inferior angle of the right scapula - typically precipitated by fatty meals - bilious vomiting - fever NOTE: caused by acute inflammation of the gall bladder, usually it is secondary to cholelithiasis

2 types of variation

1. Common cause variation - Is inherent in design of the process - results from a "stable" process that is predictable - every system has common cause variation - if you only see common cause variation, it tells you to investigate usual procedures ** Change the process - DOES NOT mean "good variation": it only means that the process is stable and predictable ex: if a pts systolic BP consistenly varies between 160-170mmHg, it might be stable and predictable but it is not good for the pt 2. Special cause variation - Is due to outside or unusual changes that are NOT inherent in the design of the process - results from an "unstable" process that is NOT predictable - If you see special cause variation, look for an unusual process acting on or changing a stable process ** Investigate causes - may represent a very good result (ex. a low turnaround time), which you would want to emulate and promot - it merely means that the process is UNSTABLE and UNPREDICATBLE ** Shifts and Trends are signals of special cause variation Shift: >/= 6 consecutive points either all above or below the median (points on mediant dont count) Trend: >/= 5 consecutive points all going up or all going down (only one point counts when two have the same value Run: points in row on one side of median; too many or too few runs crossing median is a signal Astronomical point: obvious deviation (not necessarily highest or lowest point)

Venous Drainage of the Heart has 2 pathways which are:

1. Coronary Sinus and its tributaries: (gives 99% of venous blood) - Great Cardiac Vein - Small cardiac vein - Middle cardiac vein 2. Anterior cardiac veins - drain directly into the Right Atrium

What are four modes of sodium absorption by the intestine?

1. Cotransport with monosaccharides and amino acids (symports) Ex. SGLT-1 symport with glucose - sodium-potassium pump moves sodium into interstitial fluid (active part of secondary active transport) - mainly in jejunum and ileum * associated with absorption of carbohydrates and AA 2. Na-H exchanger (antiport) - mainly in duodenum and jejunum * associated with absorption of dipeptides and tripeptides 3. Parallel Na-H and Cl-HCO3 exchangers (twin antiports) - mainly in ileum and proximal colon * associated with mass absorption of NaCl and water 4. Epithelial Na+ Channel (ENaC) - mainly in the distal colon * associated with finer control of plasma sodium and potassium

Blood Flow through the heart

1. Deoxygenated blood to Superior vena cava 2. Same to Inferior Vena Cava 3. Right atrium 4. Tricuspid valve 5. Right ventricle 6. Pulmonary valve 7. Pulmonary artery (to the lungs) 8. Pulmonary veins (from the lungs)- NOW oxygenated 9. Into the Left atrium 10. through the Mitral (Bicuspid) Valve 11. into Left ventricle 12. out through Aortic Valve 13. to the Aorta - Oxygenated blood out to systemic circulation-

Measurements can be used for

1. Improvement- Process - Understand a problem - confidential to avoid defensiveness - motivate desire for change - brief, small tests of change - obtain "just enough data: - accept consistent bias ** Measurement for improvement are not useful for external reporting and if used externally may poison the improvement effort Ex: Avg number of times pts receive recommended oral care in 24 hrs 2. Accountability/Judgement- Outcomes - External monitoring & comparison - Nonconfidential/judgement expected - monitor trends - long time intervals - obtain 100% of available, relevant data - evaluate current performance - used to reduce bias Ex: Hospital rate of HAI compared to state rate 3. Research- Complex Data - precise, valid, reliable measures - control all possible factors - inform others and publis - slow, expensive, elaborate - eliminates bias Ex: Rate of hospital- acquired pneumonia pre 10000 catheter days in ICU *** When measuring data - select items to be measured with great thoughtfulness - carefullt design sampling strategy and data collection techniques - avoid conclusions that exceed the limitations of the methods

Functions of the oral cavity

1. Ingestion of foods: usually a voluntary acivity preceded by food processing/cooking 2. Mechanical Digestions (chewing) breaks up food chunks: tongue and teeth help, the motility also mixes saliva with food 3. Chemical Digestion (salivary amylase, lingual lipase) begins 4. Absorption in the oral cavity is MINIMAL: limited time for absorption, small surface area, most nutrients still req. digestion, some drugs (ex. Nictoine) can be administered via oral absorption ** one of most important fxs of lips and tongue is sensory- detects unswallowable material and allows for one to spit it out- but for this module assume that all food is properly ingested

Common causes of R heart failure

1. L sided heart failure (most common caused) 2. Right sided MI 3. Cor Pulmonale (due to pulmonarty HTN) Sxs and Symptoms - valve pathologies can be suscultates (murmurs and heart sounds) - peripheral edema and elevated jugular pulse can be seen and palpated - hepatomegaly, elevated levels of bilirubin causing jaundice, elevated AST and ALT which signal liver damage - RAD can be seen on ECG *NOTE: pulmonary HTN does not usually evole to chronic state like in systemic HTN - so pulmonary HTN gives acut afects of high afterload- whichc begins with an increase in ESV in the ventricle

With lateral body folding the body cavities are formed, which are

1. Pleural 2. Pericardial 3. Peritoneal: the peritoneal cavity is divided into two comparment after roation of the foregut: Lesser Sac (omental bursa) and the Greater Sac (these two sacs are connected by the epiploic foramen of Winslow NOTE: the primitive gut tube is ONLY suspended by a DORSAL mesentery ** There is however also a VENTRAL mesentery which is associated with the foregut ----- We learned that the stomach rotates during development- this clockwise rotation results in: - R and L vagus nerves becoming anterior and posterior and dorsal and mesenteries rotating - Greater and lesser sacs formed with the epiploid foramen which is a way to communicate between the two

What are the 3 parts to defecation

1. Role of ENS and PNS 2. Filling the Rectum 3. Emptying the Rectum

Describe the synthesis of Glycero-phospholipids (phosphatidol- inositol, choline, ethanolamine, glycerol)

1. Starts with Glycerol-3-phosphate we can get glycerol phosphate either from: - DHAP via glycolyis or - phosphorylation of glycerol (in liver only, bc only liver has glycerol kinase- this is TAG degradation) * this is usually in gluconeogenesis but can be used in lipid synthesis ----- - two fatty acids are then added: the first is typically saturated, whereas the midd. FA is typically unsaturated - end up with phosphatidic acid which can be converted to diacylglycerol (DAG)- either one of these can have headgroups added to complete glycerophospholipid synthesis --- 2. In order to add the headgroups you must first prime the substrates with cytidine triphosphate - primer either phosphatidic acid (PA) or a headgroup with cytidine diphosphate (CDP) PA can either react with - glycero-phosphate to form phosphatidyl glycerophosphate- this is not typically a membrane constituent but can be made into cardiolipin or - inositol to make phosphatidyl inositol (PI) Headgroups primed with CDP (choline, ethanolamine, or other alcohols) can react with DAG- the final glycerophospholipid is formed * for phosphatidyl glycerol- glycerol phosphate is added and the phosphate on the glycerol is subsequently removed ** THIS DOES NOT HOLD TRUE FOR PHOSPHATIDYL SERINE

Right Atrium receives venous blood (poorly oxygenated) from 4 sources, which are

1. Superior Vena Cava 2. Inferior Vena Cava 3. Coronary Sinus 4. Anterior Cardiac Veins

What are the heart borders & surface anatomy

1. Superior: R and L Atria and auricle (L atria more seen post.) 2. Inferior (AKA diaphragmatic border): L ventricle and MAINLY the R ventricle 3. Right border (right 3rd rib and 6th rib at right parasternal borders): R atrium, SVC, IVC 4. Left border (Left 2nd rib and 5th intercostal space at midclavicular line*): Left ventricle mainly and the left auricle

Characteristics of mucosal defense:

1. The epithelium is the main physical barrier (skin), secretions provide chemical defense while resident and recruited cell provide biological defense 2. Effector cells induces at one mucosal site are imprinted with receptors that enable them to respond to homing signals back to the mucosal system (ex. if you induct cell at GI- it can go anywhere in the body but tends to go back to GI mucosa) 3. Inflammation at mucosal surfaces is normally DISCOURAGED through the activity of T regulatory cells and the production of anti-inflammatory cytokines

Tunica of Blood vessels (arteries and veins) USUALLY contains 3 Layers, which are:

1. Tunica Intima (associated with inner lumen) ** this is the ONLY layer found in capillaries 2. Tunica media 3. Tunica adventitia (externa)

As intensity of aerobic exercise increases, oxygen consumption increases- the body meets these needs for more oxygen in two ways:

1. blood flow to active muscle increases - CO is increased (SNS) - local vasodilation increases blood flow to activ emuscles (metabolic theory) 2. active muscle extracts more oxygen from the blood

In vascular fx curve 3 parametes will DECREASE venous retunr and CO

1. decrease in blood volume 2. increase in venous compliance 3. increase in arteriole resistance

Two origins of the right atrium

1. from the original primitive atrium 2. from the right horn of the sinus venosus

The hear is a dual pump- it serves 2 circulations which are linked in SERIES- which are

1. systemic circulation 2.pulmonary circulation ** each receives and ejects the SAME volume of blood/min (L/min) *** whatever R side of heart pumps to lungs --> L side of heart pumps to the rest of the body ------- It is very important that ventricular outlflow is similar in each ventricle Ex. if R ventricle pumped 1mL more/beat than L then almost the entire blood volume would be displaced to the lungs within an hour - this does NOT occur in healthy heart - as the increased pulmonary pressure will increase LAP and therefore ventricular filling via the Frank starling law, the additional blood will be ejected by the LV

Thoracic cavity is divided into 3 compartments which are

2 lateral pleural cavities: contain the lungs 1 central MEDIASTIUM: contains many things including thymus, heart, pericardium, great vessels, trachea, esophagus, thoracic duct, azygos venous system

Cholecalciferol (VitD) from light conversion or dietary ergocalciferol go to the liver where they are convereted to

25-OH D3 (calcidiol) - Calcidiol then travels to the kidney where it is converted to 1,25 diOH-D3 (calcitriol) **** this conversion is regulated by phosphate levelsand parathyroid hormone (low phosphate levels increase conversion, presence of PTH increases conversion), Calcitriol also has feedback inhibition on itself. - Calcitriol (is a nucler hormone receptor ligand) acts through intracellular receptors and regulates gene transcription to increase Ca2+ binding protein levels in the intestine ** changes in protein levels increases intestinal Ca2+ absorption ***calcitriol along with PTH increase calcium resorption from bone BOTH mechanisms act to increase circulation calcium Kidney re-uptake of calcium is increases, lowering renal excretion of calcium CLINICALLY: Calcidiol rather than calcitriol is measured as an indicatore of VitD levels

Lactase should inactivate around

3-5yrs old - Adults with non-persistance of lactase (loss of lactase production wth age) frequently develop abd pain, cramping, distension, flatulence and diarrhea (these sxs are caused by malabsorbed lactose which draws water into the intestinal lumen producing osmotic diarrhea) - intestinal flora metabolizes unabsorbed lactose to acids H2, methane and CO2 - Lactase deficiency is an autosomal recessive gene which occurs in infancy - Lactase persistence is an autosomal dominant gene NOTICE that - tolerance is the mutation (most prevalent in "cheese countries") Diagnosis for lactose intoleranc: Hydrogen Breath Test to measure H2 levels in the breath

1 cal=

4.18 joules - one calorie= the energy req. to heat 1 mL of water 1 degree celsius - a large calories= a Cal= 1,000 caloiries 1 Cal= 1000 cal= 1kcal * the large Cal is what is used in food nutrition labeling so kcal=Cal

Which rib articulates with the sternum ath the xiphisternal joint?

7th rib

Menetrier's Disease

A RARE disease in the stomach - characterized by hypertrophic and hyperplastic changes - hypertrophy of muscularis - hyperplasia of rugae

Flail Chest

A life threatening unstable injury of the thoracic wall - Multiple rib fractures detach part of the thoracic wall from the rib cage - The detached part is subjected to unopposed intra-pleural pressure resulting in PARADOXICAL MOTION seen durng the breathing cycle So In inspiration: when thoracic cavity expands, the damaged portion is sucked IN by negative pressure In expiration: when the thoracic cavity moves in, the damaged segment is pushed OUT by positive pressure

Endothoracic Fascia

A loose CT that separates the inner surface of the thoracic wall and the parietal pleura (acts like glue between the parietal pleura and thoracic wall)

All 4 heart valves are supported by

A rigid FIBROUS CT, leaflets (cusps) and chordae tendinae which are all derived from the cardiac FIBROUS skeleton - there is an overlying layer of endocardium

Posterior sheath can be found

ABOVE the arcuate line NOT below

Gastroschisis

AKA cleft stomach - this is a rare problem, which occurs in 1/3000 births and there is currently no known cause - occurs when there is a defect in the ventral abd. wall allowing protruding of viscera - a baby who is born with gastroschisis may have associate malabsorption, from partial bowel obstruction - associated with increased alpha fetaprotein during pregnancy - high mortiatily rate - Tx: push intestines back gradually as baby grows

Kwashiorkor

AKA the "disease of the disposed baby, when the next one is born" - bc first baby wheened off breast milk Diet inadequate, particularly in protein, associated with high-carb subsistence diet - common at ages 1-4 Symptoms: pot belly, enlargedfatty liver, hypoalbuminemia- which causes pitting edema, muscle wasting is masked by edema * Marasmus Kwashikor combines symptoms of both protein and energy deficiency

Atrial Septal Defects

Account for apprx 10% of all Cong. Heart Defects (probe patent foramen ovale excluded) - seen more frequently in FEMALES than males - the lesion consists of an abnormal opeing between the atria 1. Probe patent foramen ovale 2. Ostium Secundum defect 3. Endocardial cushion defect with ostium primum defect 4. Sinus venosus defect 5. Common atrium ** theres are Acyanotic

What is the critical event in pancreatitis?

Activation of precursors (proenzymes) into active enzymes leading to autodigestion of tissues EX: Acinar cell injury leading to premature activation of trypsin --> autodigestion of pancreatic tissue ---> local and systemic manifestations Locally: Pancreatic edema, necorsis, and hemorrhage Systemically: capillary leakage (loos of protein from circulation), Gut barrier breakage (bacterial translocation), Alveolar damage (impaired gas-exchange) ----> can lead to Systemic Inflammatory Response Syndrome, Adult Respiratory Syndrome, Acute Tubular Necrosis - Acute inflammation is in response to tissue damage - OUTCOME can be either: Resolution, Sepsis, Shock, Chronic Pancreatitis

Between the values of RDA (recommended dietary allowance) and Tolerable upper intake levele (UL) one can find

Adequate intake (AI): this is the value used when evidence is insufficient to develop an RDA and is set at a level assumed to ensure nutritional adequacy

densities on xray from increasing density

Air (least dense) --> fat --> water --> bone --> metal

Dietary Concerns in regard to Alcohol

Alcohol yields 7Cals/g (these are empty calories) - alcoholism can lead to decreased appetite, and thus diminished intake of nutrient-dense diet--> can lead to general malnutrition, particularly of protein, also vitamin deficiencies - high conc. of alcohol lead to B12 deficiency by decreasing the production of intrinsic factor - alcohol interferes with thiamine absorption Dietary recommendation (if consumed): - men <2 drinks/day - women <1 drink/day calories should be counts (7Cal/g) ** 1 drink equivalent= ~ 0.6oz neat EtOH ~ one normal beer ~ one 5 oz glass of wine ~ one shot 40% liquour 0.6oz EtOH = 14g ~100 Cal

What are two major types of bile acids?

All are ultimately derived from cholesterol; all have a hydrophilic side and a hydrophobic side Each modification changes solubility from the "level" before it-- cholesterol to primary AAs, primary AAs to secondary AAs, either from unconjugated to conjugated and back Primary Bile acids: made by hepatocytes from cholesterol- Enhances solubility, allows for "soap action" of bile acids, particularly when changed to bile salts - these have enough -OH groups to make a wall Secondary Bile acids: modified from primary bile acids by intestinal and colonic bacteria. Generally DECREASES solubility, though not enough that they cannot travel through the blood back to the liver (enterohepatic circulation) - these can be reconjugated into bile salts for re-use

the half life of which CCB agent is longer than the others

Amlodipine

Starch (a dietary carbohydrate) includes

Amylose (linear, unbranched and more tightly folded into a helix, more slowly digested) and Amylopectin (branched, more hydrated, readily digested) - both must be cooked to be effectively digested- how long they are cook affects the speed of digestions and the glycemic index

Collateral Circulation betwwn the foregut and midgut includes

Anastomosis between the foregut and midgut: - Superior pancreaticoduodenal aa. - Inferior pancreaticoduodenal aa.

Collateral Circulation between the midgut and hindgut includes

Anastomosis between the midgut and hindgut: - SMA--> Middle Colic A. - IMA---> Left Colic A.

Venous drainage of the Scrotum includes

Anterior Scrotal Veins - drain into EXTERNAL pudendal v. and Posterior Scrotal Veins- drain into INTERNAL pudendal v.

What are the close anatomical relationships of the spleen?

Anteriorly: stomach Posterolaterally: Diaphragm: left dome and Ribs 9,10,11 Medially: Left colic flexure Inferiorly: Left kidney and Tail of the pancreas ** spleen has impression due to these close relationships (ex. Gastric area, renal area, colic area)

Presence of acid in the gastric lumen would stimulate

Antrum D cells (indirect) this would secrete more somatostatin and shut down production of too much stomach acid

Truncus arteriosus gives rise to the

Aorta and Pulmonary Trunk

ApoC-I, ApoC-II, and ApoC-III function in

ApoC-I and ApoC-II - readily transferred between lipoprotein classes - C-II activates LPL ApoC-III - INHIBITS LPL **** C: regulates lipoprotein lipase (LPL) for release of fatty acids to peripheral tissues

Minor Salivary Glands

Are scattered throughout the submucosa of the lips, cheeks, tongue, soft palate and floow of the mouth - secrete into the oral cavity through many short ducts - with the EXCEPTION of Von Ebners Glands (associated with the papillae of the tongue) they are ALL seromucus glands but differ widely in the proportion of serous and mucus acini

Types of Blood Vessels in the body:

Arteries - Large elastic - Medium muscula (distributing) - Arterioles Capillaries - Continuous - Fenestrate - Sinusoidal Veins - Venules - Medium or Large Sized veins (the only distinction between these two are the size) -------- AS you leave the L ventricle blood travels first to: Elastic aa.--> Muscular aa. --> arterioles --> (may or may not go to capillaries: continuous capillary --> fenestrated capillary) --> venule --> medium-sized vein --> large vein --> Right atrium of the heart

Describe the control of secretion (including both ion channels & exocytosis) in pancreatic acinar cells

As in many other secretory cells of the GI, secretion of Cl- ions is followed by sodium and water, and in this case is accompanied by exocytosis of many proteins including digestive enzymes - for both chloride secretion and exocytosis, the phospholipase C-induced pathway plays a larger role than does the adenyly cyclase-mediated pathway - and the two major signal molecules for these are the PNS NT ACh and the hormone cholecystokinin (CCK) - However, for full stimulation of secretion, adenylyl cyclase must also be activated, and this requires both PNS neurons using vasoactive intestinal peptide (VIP) and the hormone secretin * when both second messenger systems are activated, they potentiate one another, producing levels of secretion greater than that of just adding the levels produced by either AC or PLC pathways ----- Main point: - chloride is secreted - sodium, water follow - exocytosis of pancreatic proteins

Excess fluid in the peritoneal cavity is referred to as

Ascites

Which neuronal plexus can be found in the Muscularis Externa of the small intestine?

Auerbachs (myenteric) plexus (motor innervation) - it is found in between the inner circular and outer longitudinal muscle layers

odds ratio=

AxD/BxC -- odds ratio less than one- decreased likelihood of risk factor being associated with outcome

ENS sensory information is sent to

BOTH ENS control plexuses (myenteric and submucosal) and then ENS motor neurons originating in there plexuses alter muclse and glandular activity

The lateral domain of hepatocytes form the

Bile canaliculi, which receives the livers' exocrine secretion (bile) - leakage of the bile from the canaliculi is prevented by tight junctions (Zonula Occludens) between adjacent cells. Gap junctions are also present for communication

Stimulant Laxatives include:

Bisacodyl and Senna Pharmacological Effect: - Increased GI motility Pharmacokinetics: - Oral onset 6-12hrs - Rectal onset 1-3hrs (Bisacodyl comes as suppository with faster rectal onset) Adverse Effects: - nausea, vomiting, cramping - atonic nonfunctioning colon (this is why recommended use is 10 days or less) - inflammatory response to small bowel and colon - colonic ischemia Clinical Use: - Constipation - Adjunct for colon cleansing before colonoscopy (co-administer with osmotic laxative)

Minerals include

Boron Calcium Chromium Copper Fluoride Iodine Iron Magnesium Manganese Molybdenum Nickel Phosphorus Selenium Vanadium Zinc *** these have many upper limits that if passed can lead to deleterious health effects * except chromium has no upper limit

What inguinal contents do both males (wider canal) and females (narrower canal) have in common?

Both males and females contain the following in their inguinal canals: - Ilioinguinal nerve - Genital branch of genitofemoral nerve - Blood and lymphatic vessels ONLY males will transmit the spermatic cord and therefore, all of the cords contents and ONLY females have the round ligament of the uterus (remember this was a remnant of the gubernaculum)

Drugs that work as Laxatives can be divided into:

Bulk- Forming: - Methylcellulose Stool Softeners: - Docusate - Mineral Oil Osmotics: - Polyethylene glycol - Lactulose Stimulants: - Bisacodyl - Senna

Anti-Oxidant Vitamins include:

C and E (sometimes A) - Ascorbic Acid (vitC): is water-soluble - Vit E (tocopherols): is fat-soluble - VitA can also be an antioxidant but has other important roles as well

Short and Medium chain fatty acids (FA) have lengths of

C4 to C12 - C3 and C4 created by microbiota (NOT our diet) - DO NOT require bile salts to be soluble - Enter enteric blood and are collected by the liver for storage or use as needed

MAP=

CO x TPR - body maintains MAP by adjusting CO and TPR

What is CTR

Cadiothoracic ratio - ratio of max horizontal cardiac diameter to max horitzontal thoracic diamter (inner edge of ribs/edge of pleura) CTR= cardiac width/thoracic width

Sources of Vit A, retinol include

Carrots, vegetables and fruits (yellow, green and orange ones), liver, kidney, meat, eggs, cream, butter Deficiency (is RARE in modern world) - common in developing countries - sxs: night blindness, eventual loss of retinal cells - Xerophthalmia: dryness of conjunctiva and cornea caused by keratin synthesis * Retinoic acid can be used to treat psoriasis and acne Toxicity: Hypervitaminosis A - characterized by dry skin, enlarged and eventually cirrhotic liver, increased intracranial pressure * this is one of the reasons that eskimos no longer eat polar bear liver bc it has soo much VitA that it can lead to this

PV loop changes in LV heart failure (Diastolic Dysfunction)

Cause Systemic Hypertension: Decreases: - ventricular compliance: associated with concentric ventricular hypertropy - filling and therefore preload - EDV, EV - stroke work Increased: slope of EDPVR line Ejection fraction has little changes (i.e. HFpEF= heart failure with preserved ejection fraction) ** this increases slope of end-diastolic-pressure-volume-relationship (EDPVR)

First part of the Large Intestine that is continuous with the ascending colon:

Cecum - in right lower quadrant (RLQ) --> iliac fossa close to the inguinal ligament - intraperitoneal organ as it can be lifted relatively freely and is entirely covered in a visceral layer of peritoneum - bound to the post. abd wall by cecal folds instead of having its own mesentery (still intraperitoneal though) - arterial supply is via ileocolic artery which is direct branch of the superior mesenteric artery

Sensitivity to Gliadin Protein in gluten found in wheat, rye and barely

Celiac Disease/Gluten enteropathy Results in: - chronic active inflammation of the bowel (mainly characterized by lymphocytes- "lymphocytic infiltrate") - subacute inflammation - chronic inflammation: lymphocytes and macrophages ----- NOTE: Some diseases can be characterized by "chronic" inflammatory cells WITHOUT a preceding "acute type" inflammatory response dependent on: what triggers the respongs, the type of cells activated and attracted to the site by release of chemicals by cells (cytokines)-- this determines what is seen on the microscope (ex. Lymphocytic infiltrate in Celiac Disease

The Lymphatics of the Spleen ultimately drain by following the arteries towards the

Celiac Lymph Nodes

The lymphatics of the stomach ultimately drain by following the areteries to the

Celiac Lymph Nodes

Lymphatics of the gallbladder are ultimately drained by following the arteries towards the

Celiac Lymph nodes

Lymphatics of the Pancreas ultimately drain by following the arteries and drain into the

Celiac Lymph nodes or Superior Mesenteric Lymph Nodes

Describe the mucosa of the Small Intestine (duodenum, jejunum, ileum)

Characteristic feature are the villi/crypts which are thrown into transverse folds known as the plicae circulares * plicae circulares is associated with surface projections

Elastic Laminae

Characteristic feature of elastic arteries - thin sheets of elastic fibers in the tunica media of elastic arteries Holes in the elastic laminae allow: - nutreints and oxygen to diffuse through layers - process of SMCs contact each other across layers

Anuerysums (not related to atherosclerosis)

Charcot- Bouchard: anuerysm of small cerebral aa Berry: inherited anuerysm at circle of willis in base of brain

Vitamin B5, Pantothenate is a constitutive part of

Coenzyme A (CoA) - a coenzyme in fatty acid synthetase * it is common in the diet: not known to have a deficiency under ordincary conditions - No RDA

Tetralogy of Fallot

Collection of 4 abnormalities by the same primary defect Unequal division of the truncus arteriosus caused by anterior displacement of the aorticopulmonary septum - R to L shunting of blood after birth Displacement of the septum produces 4 classic cardiac defects 1. Pulmonary Stenosis 2. Ventricular Spetal Defect (membranous type) 3. Overriding Aorta (rightward displacement of the aorta) 4. Right Ventricular hypertrophy caused by higher pressure on R side ** Constellation of abnormalities leads to poor oxygenation of body, CYANOSIS- less blood reaching the lungs (depends on degree of stenosis)

Potassium Secretion only occurs in the ___, typically during dehydration

Colon Potassium has two type of secretion Passive secretion: - paracellular - greatest in DISTAL colon - follows increased electrical gradient and Active secretion: (only if you have desperate need to get rid of K+, ex. having arrythmias) - transcellular - more in PROXIMAL colon than in distal colon - stimulated by aldosterone on surface epithelial cells (ex. in kidney, active potassium secretion is secondary to trying to maximize sodium and water retention in blood via aldosterone) OR.. - stimulated by cAMP activation in intestinal crypt cells - increased number/activity of apical potassium channels

Diverticulosis

Colonic diverticula are herniations of the mucosa and submucosa through the colonic wall - if ASYMPTOMATIC this finding is called diverticulosis - intraluminal pressure is high during segmentation in the sigmoid, so this is the most common site of diverticula formation - most commonly located in the aread between the mesenteric and the antimesenteric taenia - the mucosa and submucosa bulged out through the focal weak areas of the colonic wall, usually in an area of vessel penetration, creating multiple false diverticula ** If a fecalith gets stuck here it can infect/inflame and if it perforates an artery it can cause sxs of Diverticular Disease

Celiac Trunk (AKA Celiac A.) which supplies the foregut (and spleen) has 3 branches which are

Common Hepatic Artery Splenic Artery Left Gastric Artery ----- Common Hepatic Artery branches into the - Gastroduodenal artery - Hepatic Artery proper (proper hepatic artery) Splenic Artery branches into the - Short gastric artery - Left gastro-omental artery Left Gastric artery branches into the - Esophageal branches ------------------- Gastroduodenal Artery branches into the - Right gastro-omental artery - Supraduodenal artery - Superior pancreaticoduodenal arteries (Anterior and Posterior) Hepatic Artery Proper (Proper hepatic artery) branches into the... - Right gastric artery - Left hepatic artery - Right hepatic artery - Cystic artery ----------- NOTE: Celiac trunk gets - Parasym Innervation via Vagus nerves (CNX) - Symp. Innervation via Thoracic Splanchnic Nerve (T5-T9) for Pre-ganglionics and vis the Celiac Ganglion for Post-ganglionic cell bodies

Root of 5th intersegmental artery (5ISA) forms the

Common iliac arteries - they also give rise to external iliac arteries and proximal segment of internal iliac arteries *** The R and L umbilical arteries arise in connecting stalk (future umbilical cord), early in 4th week - initially they are connected to dorsal aortae in sacral region - loss of connection of dorsal aortae in fifth week and connect to proximal segment of internal iliac arteries *** So umbiliac aa--> distal internal iliac aa

Vascular compliance

Compliance= change in volume/ change in pressure - compliance is indiacted by the slope of the cuve (increased slope= increased compliance) - veins "venous compliance" exhibit high compliance when at low pressure, compliance decreases at high pressure - arteries exhibit low compliance at BOTH low and high pressures *** at higher pressures and volume, venous compliance (slope of compliance curve) becomes similar to arterial compliance- this makes veins suitable for use as arterial by-pass grafts ** An artery can be respresented by a balloon with more elastic walls whereas the a vein is better represented by a polythene bad, where the walls are much less elastic and therefore more compliant

Metarteroiles

Connect arterioles to capillary networks - NO TRUE tunica media - Presence of a precapillary sphincter: a single SMC that encircles the metaarteriole at the metarteriole-capillary junction- it regulates the flow of blood into the capillaries Constriction of precapillary sphincter - blood bypasses the capillaries and passes through a thoroughfare channel to the venule - this is a type of shunt system - located in fingertips, nose, lips, and erectile tissue - functions in thermoregulation and erection

Types of Capillaries

Continuous (somatic) - solid endothelial layer (tunica intima) and basement membrane Fenestrated (visceral) - Fenestrations Sinusoid (sinusoidal/discontinuous) - Intercellular gaps and incomplete basement membrane

Ventricular muscle (myocytes)

Contractile Myocardial cells - prodce FAST response action potential

Barium Enema

Contrast is inserted into the pts anus and various images are taken while pt lays down- rotating sides to move the barium along ** this allows for a very good view of the entire bowl ** Colonoscoy and Barium Enema can be used to view Colonic Diverticula

ATP7A and ATP7B are

Copper translocases - mutation in ATP7A gene, which normally encodes Intestinal Cu+2-Translocase --> Menkes Disease - mutation in ATP7B gene, which normally encodes Cu+2-ATPase --> Wilsons Disease

67 y/o male collapses at work - autopsy shows ischemic heart disease most likely caused by

Coronary artery artherosclerosis *** this is most likely cause of ischemic heart disease

Gallbladder receives its arterial supply via the

Cystic Artery - the cystic artery is highly variable, however, it most commonly branches DIRECTLY from the Right Hepatic Artery ** REMEMBER if you are removing your gallbladder you need to ligate the blood supply to this area

Identification of which triangle can aid in identifying a variation in the cystic artery or biliary apparatus

Cystohepatic Triangle usually: R. hepatic artery --> cystic artery variation: L hepatic artery --> cystic artery *** NOTE dissection of this triangle is key in performing a safe laparoscopic cholecystectomy The borders of the triangle are: (*these 3 boundaries vary from the origianl thesis from Dr. Calot in 1891) 1. Superior: Inferior border of the liver 2. Medial: Common hepatic duct 3. Lateral: Cystic duct

CCBs pharmacological activity on nodal tissues (SA and AV nodes)

DHPs: - decrease current in dose-dependent fashion BUT they do NOT effect the rate of recovery (ROR) of the calcium channel (not clinically useful) - action is independent of frequency of stimulation NON-DHPs - decrease current and decrease ROR of the calcium channel - action is dependent on frequency of stimulation (more freq. stimulation leads to more block) - decreased rate of SA node pacemaker (lowers HR) - decreased AV node conductance (decreases signal velocity) (ex. increased refractory period)

Primary bile acids are made

DIRECTLY from cholesterol

SMALL cystic veins drain

DIRECTLY into the liver

If MAP increases: Then the efferent activity in bulbospinal pathway, activity of pre-ganglionic symp neurons, TPR, output from the vasomotor center, slope of phase 4 of AP in SA node, cAMP concentration in cardiac cells, circulating levels of epinephrine, flux through L-type Ca channels, and rate of sequestation of Ca by sarcoplasmic reticulum all Increase of Decrease?

Decrease! * efferent activity in bulbospinal pathway would decrease bc you have inhibited via GABAergic neuron

Entrance of the Inguinal Canal is the

Deep Inguinal Ring (AKA "internal" inguinal ring) - opening in the transversalis fascia where it lies - located 1/2 way along the inguinal ligament - LATERAL to the inferior epigastric artery and vein

Describe the Filling of the Rectum in defecation:

Defecation Reflex (ENS-based with parasympatehtic assist): gets motility greater to make sure it occurs 1. secretion of lubricating mucus into rectum (and anal canal)- to make sure solid mass keeps moving along (reduced resistance to flow) 2. mass movement to fill rectum 3. filled rectum passively distends chamber * If sufficiently full (if passive distension of rectum is sufficiently large), triggers active contraction of rectal smooth muscle to occur via ENS - drives material to the anal canal, also movement of the pelvic wall to decrease angle between sigmoid colon and rectum to make easier movement through *** this active contraction of rectal smooth m. facilitates defecation by increasing the pressure in the rectum relative to the anal canal

Portal Hypertension

Defined as an increase in pressure of the blood travelling in the veins of the portal system - Venous blood draining away from the GI tract usually drains to the liver before draining into the IVC.. so if the route of the liver is obstructed then the reverse (collateral) flow from the portal systemic veins through the caval system veins instead can divert blood to the heart insted of the liver * The small caliber veins of both the portal and caval system are not suited to handle this reversed blood flow for an extended period of time, as these collateral veins are forcing through a very large volume of blood *** Hepatic Causes can be due to Cirrhosis and Acute Liver Failure (an increase in fibrous tissue, consticts vasculature into liver via the Hepatic Portal Vein) ** Varices: increased portal blood pressure can result in potentially fatal, abnormally dilated veins

Absence of Hepatic Segment in the Inferior Vena Cava

Deoxygenated blood CANNOT pass into the RA in the normal manner - Result: blood from the caudal parts of the body drains via azygous and hemizygos veins and then into the SVC and RA - is usually associated with heart malformations

Stimulators of slow waves of GI smooth muscle ____ the membrane

Depolarize To help get an action potential- this is done by: - stretch - ACh (excitatory parasympathetic) - some GI hromones (ex. gastrin in stomach) * depolarizing a cell makes it more excitable

The ____ is the fourth part of the large intestine and begins at the L colic (splenic) flexure where it connects the transverse colon to the sigmoid colon

Descending Colon - in LUQ and LLQ - secondarily retroperitoneal organ - L paracolic gutter is located laterally (allows peritoneal fluid to drain superior --> inferior) - typically longer than the ascending colon - L colic (splenic) flexure is closely related to the spleen - Arterial supply via: L colic artery which is a direct branch of the inferior mesenteric artery

Gastroparesis can be seen in

Diabetics

Arterioles

Diameter 10-100micrometers - Tunica intima consists of endothelium (simple squamous) basal lamina and subendothelial layer containing SMCs * a thin internal elastic lamina may be present in large arteriole but is absent in small arterioles - Tunica media: consists of 1-2 layers of smooth muscle: control of blood flow into capillary networks - Tunica adventitia: consists of thin poorly defined sheath of CT

Muscular Arteries (Large)

Diatmeter (2-10mm) are distributing arteries and include the radial and ulnar arteries & axillary arteries - Tunica Intima: consists of endothelium, basal lamina and an underlying subendothelial layer containing SMCs * Prominent internal elastic lamina (IEL) between tunica intima and media* - Tunica media: consists of up to 40 layers of SMCs, collagen fibers and some unorganized elastic fibers ** Prominent external elastic lamina ( EEL) between tunica media and adventitia is present in large muscular arteries and is absent in small musclar arteries - Tunica adventitia consists of CT and elastic fibers- it is thinner than the tunica media in muscular arteries

Glycemic Index (GI)

Difference in area between the same amounts test carb food and control glucose bolus (50g as glucose or white bread) - high GI foods (GI>70) : white rice, white bread, potatoes (near 100) - low GI foods (55>GI): rolled or steelcut oatment, whole wheat breach, pumpernickel bread, fruits, beans, peas *** Compares speed of absorption of equivalnet amts of carbs- number varies between 0-100, 100= curve for absorption of pure glucose * Note that some foods GI value depends greatly on how it is prepared (ex. oats have values that vary among all categories) * high blood glucose- high glycemic index

Which type of inguinal hernia is more common in OLDER males

Direct Inguinal Hernia

What is the most common type of Inguinal Hernia

Direct Inguinal Hernia * because weakness is MOST common in Hesselbach's Triangle which is where a direct inguinal hernia originates this triangl contains: inferior epigastric a., rectus abdominis, inguinal ligament NOTE: weakness in the ant. abd wall can cause tearing of the wall and protrusion of abd contents- this condition is called an inguinal hernia

Rib Dislocation vs a Rib Separation

Dislocation is at the sternocostal joint (costal cartilage from the sternum) Separation is a dislocation of costochondral joints

Rib Separation

Dislocation of the costochondral joints - separated rib may be displaced SUPERIORLY and often overrides the rib above

Irritable Bowel Syndrome (IBS)

Disorder characterized by cramping, abd pain, bloating, constipation and diarrhea - many possible causes including infectious agents - serotonin (5-HT) is linked with normal GI functioning - ppl with IBS may have impaired serotinergic signaling capability - other research shows a parasympathetic control path may be involved Treatments: - dietary and lifestyle changes, as well as drugs as anticholinergic agents and antiserotoninergic agents

Diverticular Disease

Diverticula associated with significant symptoms is termed Diverticular Disease Presentation/Symptoms may include: - abd pain - fever - leukocytosis - anorexia - obstipation (sever or complete constipation)

Diverticulum vs. Diverticulosis vs. Diverticular Disease

Diverticulum: a sac-like protrusion of the colonic wall Diverticulosis: presence of diverticula- implies that the diverticula are ASYMPTOMATIC Diverticular Disease: clinically significant and SYMPTOMATIC diverticulosis Ex. Diverticular bleeding, Diverticulitis, Segmental Colitis associated with diverticula, LLQ pain

Describe Sphingosine synthesis

Doing two things - oxidizind C-C bond - attaching fatty acyl-coA moiety - also collect reducing agents (FAD) and oxidize part of carbon chain into double bond -------- 1. combine serine and palmitoyl coA to make sphinganine (which is not a fatty acid ester, but makes a C-C bond with serine to form a continuous hydrocarbon chain) 2. Add a second hydrocarbon chain to the amine - forms a stable amide bond - w/o fatty acid chain this is called sphingosine ( a structural part of ceramide, but NOT an intermediate in the synthesis) - this stip also involves oxidation of the first hydrocarbon to introduce a DB 3. the product of this step is ceramide (an important intermediate and start of glycolipid synthesis- it is the basis for sphingomyelin and glycolipids)

Coronary Artery Variation

Dominance depends on the origin of the Posterior Interventricular Artery Normally (70%) of population this is a branch of the Right Coronary Artery A common varition= Is it being a branch of the Left Coronary Artery (15% of population) ** this determines the dominance of the heart

In development when the intestines re-enter abdomen the attachment of ______ to the posterior abdominal wall is greatly modified

Dorsal Mesentery - Mesenteries of ascending and descending portions of colon fixed against peritoneum of posterior abd. wall- upon fusion of these layers, these segments become retroperitoneal structures NOTE: foregut derivates the distal 2nd, 3rd, and 4th parts of duodenum, pancreas are retroperitoneal ** REMEMBER for retroperitoneal structures: "SAD PUCKER" primary retroperitoneal: - suprarenal (adrenal) glands - aorta and IVC - ureters - kidneys - esophagus - rectum: proximal 1/3rd secondary retroperitoneal: - duodenum: 2nd, 3rd, and 4th parts - pancreas: head, neck, and body - ascending colon - descending colon

Since the transverse colon as dual embryological origin it has

Dual arterial supply (bc it is from Midgut and Hindgut) - proximal 2/3rds: middle colic artery - distal 1/3rd: left colic artery

Cardiac Temponade (Heart Compression)

Due to extensive pericardial effusion - compressed volume does NOT allow for full expansion of the heart --> limits the amount of blood heart receives --> reduces cardiac output Symptoms: "Becks Triad" 1. HYPOtension: low stroke volume, low cardiac output 2. Jugular-venous distension: bc blood cannot go to SVC, so distension accomdates amount of blood 3. Muffled heart sounds (bc of pericardial effusion) Treatment: Pericardiocentesis - withdrawal of fluid from the pericardial sac - main site: LEFT 5th-6th intercostal space near the sternum or infrasternal angle

Cryptorchid (undescended) testis

Due to the testes relocating from the lumbar region down into the scrotum, it is common for this process to encounter anomalies Four degrees of incomplete (arrested) descent: 1. in abd cavity dloce to deep inguinal ring 2. in inguinal canal 3. at superficial inguinal ring 4. in upper part of the scrotum Four type of ectopic maldescent (all over the place- totally abnormal) 1. in superficial fascia (scarpa's fascia) of the anterior abd wall, above sup. inguinal ring 2. at root of penis 3. in perineum 4. in thigh --- ** this is common in premature babies (30%), 1-3% are full-term ** typically unilaterl: apprx 95% ** increased risk of developing malignancy

Elastic Arteries During the Cardiac Cycle

During Ventricular Contraction 1. ventricle contracts 2. semilunar valve opens 3. Aorta and arteries EXPAND and store pressure in elastic walls During Ventricular Relaxation 1. isovolumic ventricular relaxation 2. semilunar valve shuts 3. ELASTI RECOIL of arteries sends blood FORWARD into rest of the circulatory system

Major risk factors for atheroclerosis

Dyslipidemia: increased cholesterol and LDL, decreased HDL Smoking: endothelial injury and dysfunction HTN: vasospasm and endothelial injury Diabetes mellitus: distortion of lipid metabolism and endothelial dysfucntion Others: age, family, history, obesity, sedentary life style, etc

Clinical term for difficulty in swallowing

Dysphagia Many causes include: - CNS disorders affecting salivation and/or swallowing: rabies, poliomyelitis, encephalitis - Paralysis of swallowing muscles and/or failure of neurotransmission: muscle dystrophy, myasthenia gravis, botulism

In general, D cell secretion of somatostatin inhibits both

ECL cells and parietal cells

Which layer of the heart contains the Purkinje Fibers

Endocardium (most inner layer) - Purkinje fibers are specifically located in the Deep Subendocardial layer of the endocardium (which merges with the outer myocardium)

Function of Hepatocytes include

Endocrine function: - production and release of plasma proteins (ex. albumin, fibrinogen) -- allowed by microvilli Exocrine function: - bile production (this secretion is received by the bile canaliculi) ** NOTE: metabolic wastes, by-products of RBC destruction, and toxic substances removed from the blood are enzymatically inactivated (detoxified) in the SER and released into the bile canaliculi

Endoscopic Retrograde Cholangiopancreatography (ERCP)

Endoscope is introduced into patients oral cavity and fed through the esophagus, stomach and duodenum - X-ray contrast material is injected into the pancreatic or bile ducts - a series of xrays are taken Most common complication: pancreatitis due to irritation of pancreatic duct by the x-ray contrast material or cannula Can be used to visualize - Biliary ductal system "aka Biliary Tree" (can be used to find gallstones (cholelithiasis) and acute cholecystitis)

Extrapleural Intrathoracic Surgical Access

Endothracic fascia forms an important natural cleavage plan for surgical separation of parietal pleua from the thoracic wall

In crypt cell secretion what are all things that increase CFTR activity?

Enteric neurons - Ach (M3, + phospholipase C, PLC) - VIP ( + Adenylyl Cyclase, AC Basolateral Endocrine/Paracrine agents and some toxins: - Serotonin (5HT) (+PLC) - Prostaglandins (+AC) - Histamine (in inflammation) (+AC) - Ceratin toxins that cross cell to (+AC) Apical Agents and some toxins: - Minor hormone Guanylin (+Guanylyl Cyclase, GC) - Certain toxins that act at apical membrane (+GC) **** ALL these things above increase CFTR activity and thus crypt cell secretion- the only way to shut off CFTR is if ALL these things go away: No hormones/toxins

The ___ is an elongated, tightly coiled, convoluted tube that is located on the posterior surface and superior pole of the testis

Epididymis - Stores spermatozoa until maturation occurs - Arterial supply is provided by the testicular artery 3 part os epididymis: 1. Head: receives efferent ductules 2. Body: narrower in diameter 3. Tail: continuous with ductus deferens

What type of glands can be found in the submucosa of the esophagus?

Esophageal glands which secrete mucus

The esophagus and the cardia of the stomach meet at the

Esophago-gastric junction

Dietary protein includes both

Essential and Non-essential Amino Acids Non-essential AA: - can be synthesized de novo or from essential precursors Includes: - alanine - arginine - asparagine - aspartate - cysteine - glutamate - glutamine - glycine - proline - serine - tyrosine Essential AA: - required in the diet - NOT vitamins because they are required in substantial quantities Includes: - Histidine - Methionine - Threonine - Valine - Isoleucine - Phenylalanine - Tryptophan - Leucine - Lysine * NOTE: ALL AA can be degraded or metabolized for energy

T or F: The transversus abdominis makes a huge contribution the layers of the spermatic cord

FALSE!!!! NO!!!!!! only the transversalis fascia contributes to covering of spermatic cord and scrotum, the transversus abdominis muscle doesnt NOT

T or F: Improvement, Accountability/Judgement and Reasearch are ALL mutually exclusive

FALSE!!!! They are NOT - To improve quality of care, physicians need to build skills in all three areas ------ NOTE: - measurement of healthcare processes and outcomes influence the care that is delivered - identifying whether measures are for reasearch, judgment, or improvement is vital first step - interpreting and analyzing vartion in data (using run charts or statistical process control charts) creates useful information that proves insight into a process

Which lysosomal storage disease is the only one that is X-linked

Fabry disease (deficiency in alpha-galactosidase A) * all others are Autosomal Recessive

Persistent Truncus Arteriosus

Failure to partition truncus arteriosus (1 in 10,000 live born infants) - allways associated with VSD (membranous) - results in common outflow channel for BOTH ventricles; body and lungs receive partilly deoxygenated blood, CYANOSIS; untreated the infants usually die within the first 2 years ** Seen in DiGeorge Syndrome *** There is lots of deoxygenated blood flowing into the systemic circulation therefore cyantoic form of Congenital Heart Defect ** Right to L shunting of blood

Dietary recommendations for Fat

Fat as a percent of total calories: 20-35% (%total kcal) - limit saturated fat <10% of total kcal - essential FAs: linoleic (12/17g for F and M minimum) Linolenic (1.1/1.6g) - limit or exclude trans fats - cholesterol- NO set limit (old limit 300mg/d)

Usual size of fatty acids

Fatty acids are designated by the number of carbons - only even #s occurs normally when synthesized in the human body, but odd ones can be found in the diet - you can have 4-24 carbons *most common are in range of 16-22 carbons, but others occur as well

Longitudinal folds of the mucosa of the stomach

Gastric rugae - can be temporary: diminish as stomach distends (so they disappear when the stomach is full) - can be permanent: form the gastric canal * the gastric canal is a groove that appears along the lesser curvature during swallowing

__ is a hormone produced by the stomach during a fasting state. It acts on the brain to increase hunger and thereby appetite. It has NO direct effects on GI function

Ghrelin

LARGER cystic veins drain into the

Hepatic Portal Vein

Chest xray reveals pulmonary edema- pt has worsening orthopnea (breathlessness laying down), dyspneic with exercise but WITHOUT chest pain- most likely has

Hypertension ** will have LV hypertrophy

3 Main movements in Quiet Inspiration to Increase Thoracic Volume

I. Anterior Posterior Dimension (expanding front and back: Primarily involves 2-6th ribs II. Lateral Dimension (expanding on the sides): primarliy involves 7th-10th ribs III. Superior-inferior (vertical) dimension: as the diaphragm contracts its dome flattens ** involves external and internal intercostal and abdominal muscles

Prevalence=

Incidence x Disease - a cure discovered : decreases prevalence - effective preventrion/ vaccine: decreases prevalence and incidence

Pericarditis

Inflammation of the pericardium - causes chest pain - "pericardial friction rub" (sounds like rustle of silk) ** inflammed areas rub against eachother- no pericardial fluid to cause smooth beating heart layers instead rub together

Class III antiarrhythmic drugs block

K+ channels

The second day after an MI what may appear on pathology

Karyolysis and PMS (polymorphonuclearcytes) infiltration

Static compliance of the Aorta: The "Windkessel Effect"

Keeps blood moving during ventricular diastole - the aorta is distended during systole - then recoils during diastole, pushing blood forward through the systemic circulatory system while the ventricle fills - helps maintain coronary blood flow

The triangular ligament is formed from the

L and R Coronary Ligaments

Lymph from the testes initially drains to the

Lumber (AKA PARA-aortic lymph nodes) *"para"= around

The accessory pancreatic duct drains into the

MINOR duodenal papilla

Medium and Large Veins

Medium veins (diameter of 1-10mm) and large veins (diameter of >1cm) run with corresponding arteries - tunica intima consists of endothelium, basal lamina, and subendothelial layer containing SMCs (extends into the lumen of large and medium veins as valves) - tunica media: consists of 2-15 layers of SM and collagen fibers - tunica adventitia: consists of CT, some elastic fibers, dollagen fibers and bundles of SMCs for the purpose of peristaltic action ** Tunica adventitia is much thicker than the tunica media

Driving Force=

Membrane potential- Nernst Potential for that ion

Abdominal Exam: 4. Palpation

Method: - Palpate all areas of the abdomen, using a sequential/methodical approach will prevent missing an area - palpate on exposed abd, not on the garments - use the flat of the hand; do not use fingertips - be gentle - watch the patients face for any expressions of discomfort - perform both superficial and deep palpation - begin palpation in region furthest away from the painful area

Common causes of ACUTE abdominal pain

Most common on admission are: - Acute appendicitis - Nonspecific abdominal pain - Pain of urologic origin - Intestinal obstruction

Role of Extracellular Ca2+ in myogenic reflex

Myogenic vasoconstriction involves: 1. increased intraluminal pressure 2. stretch-insuded smooth muscle depolarization 3. opening of voltage-gates Ca2+ channels 4. global increase in Ca2+ concentration 5. myosin light chaing phosphorylation

Gangliosides are branched structures containing

NANA

Formation or development of a NEW ABNORMAL growth of tissue

Neoplasia - this is NON-REVERSIBLE - this is different from hyperplasia which is only and increase in cells and it is reversible

What occurs if we do NOT have the total 270 degrees anticlockwise rotation occur in the development of the intestines?

Non-rotation of the midgut: - occurs when midgut rotates ONLY 90 degrees anticlockwise - results in small intestine on the R side, large intestine on the left side (L-sided colon) - usually asymptomatic this is opposite of... Mixed Rotation and Volvulus: - failure of intestines to complete final 90 degreed of rotation - result cecum inferior to pylorus fixed to posterior abd wall by peritoneal bands (from duodenum) - Volvulus (twisting) of intestines impedes intestinal contents, compromising supply ** you must correct this or there will be death of tissue

Innermost intercostal muscles

Occupy the lateral most part of the intercostal spaces - muscle fibers run inferior posteriorly (just line the internal intercostal muscles but is seperated from it by the intercostal neurvascular structures- VAN) ** these had no membrane

Cyanotic Congenital Heart Diseases

Occur due to deoxygenated blood bypassing the lungs and entering the systemic circulation of a mix of oxygenated and deoxygenated blood entering the systemic circulation - results in low blood oxygen level ** Cyanosis refers to a bluish color of the skin and mucous membranes Mixed blood flow: transposition of great arteries, Truncus arteriosus Decreased pulmonary blood flow: Tetraology of Fallot

Patent Ductus Arteriosus (P.D.A)

Occurs commonly in preterm infant and in rubella during pregnancy - can close spontaenously (by day 3 in 60% of normal term neonates) - remainder are usually ligated simply and with little risk Medications: - for premature babies, may used NSAIDs such as ibuprofen (Advil, Motrin, other) or indomethacin (Indocin), to help close a PDA. NSAIDs block prostaglandin E1 that keep the PDA open

Describe the Innervation to the Spleen

Parasympathetic--> Vagus (CNX) Sympathetic --> Greater Splanchnic (T5-T9) and Lesser Splanchnic (T10-T11)

Prostaglandins inhibit the AC pathway- leading to decreased gastric acid secretion by inhibited

Parietal cells (direct effect) * direct means the action is directly on the parietal cell that secrets HCl

Pericardial Effusion

Passage of FLUID from pericardial capillaries into the pericardial cavity (or pus accumulation ** pus can have a solid component) Ex. Bulbous ("water bottle") heart ** If pericardial effusion is extensive it can lead to Cardiac Tamponade (Heart Compression)

Describe the process of emptying the rectum in defecation:

Passive rectal distension relaxes the internal anal sphincter - the reflex response of the external anal sphincter is to contract, if defecation is not desired - if defecation is desired, relaxation of the external anal sphincter is VOLUNTARY * Deliberately increasing abdpelvic pressure by straining, or changing body position to lessen angle between rectum and anal canal is also voluntary- this is called Valsalva Maneuver ( used in vomiting also) * with sufficient pressure gradient, the feces will be removed from the body

CCBs affect which phases in Action Potential Conductance

Phase 0: Upstroke (opening of L-type Ca2+ channels and influc of ca2+ and Phase 4: at -55mV opening of T-type Ca2+ channels and when threshold of -40mV reaching opening of L-type Ca2+ channels generating upstrole of next AP *** L-type calcium channels "trigger" at threshold, influx of calcium in phase 0 takes membrane potential to point where K+ channels push MP to depolarized state

Phosphatidylcholine and Phosphatidylethanolamine are similar except that

Phosphatidyl choline has 3 methyl groups - choline a trimethylated ethanolamine - it is the MOST common phospholipid - choline can be synthesized in body but NOT sufficient quantity- so its also req. in diet - phosphatidyl choline can serve other fx. * infants born prematurely without DPPC can lead to infant respiratory distress syndrome --- Phosphatidyl-ethanolamine (PE) - principal constituent of bacterial membranes - common constituent of eukaryotic/mammalian membranes

phosphatidyl serine must become what before becoming phosphatidlycholine

Phosphatidylethanolamine PS --> PS --> PC

The rough part of the ventricles are made from the

Primitive Ventricle

L sided heart failure usually accompanies or preceds

R sided heart failure

Which gastric motility effectors slow gastric emptying

Reduced pressure and increased resistance are needed Slowed motility and reduced pressure occur via: - Fat in gastric lumen - NE - GIP *** sympathetic (inhibitory)- shuts down gut, your gut will shut down if youre nervous enough Increased resistance, by increasing pyloric tone is done by: - Intrinsic signals (distal to pylorus) - CCK - Gastrin - NE (symp.- sphincter tightens) - ACh (vagus) *** sympathetic AND parasympathetic (excitatory): the balancing of both of these allows for "fine control"- lets the pyloric sphincter not be too open or too closed

Hydronephrosis can be properly viewed on a

Renal ultrasound

Metaplasia

Replacement of a mature (differentiated) cell (tissue) type by another differentitated type Ex. Barrett's Esophagus

Left SVC in isolation

Resulting from failure of the Left anterior cardianl vein to become obliterated NO left brachiocephalic vein in this condition as it develops from an anastomoses between Left and RIght anterior cardinal veins when the CAUDAL part of the left anterior cardinal vein degenerates - Also obliteration of common cardianl and portion of anterior cardinal on the right take place (so there is NO right SVC formed) Result: Blood from the R side drained by the persistent left superior vena cava into the RA through the coronary sinus - Coronary sinus enlarges to cope with increased blood flow

Which are your TYPICAL ribs?

Ribs 3-9 - in the costal groove runs the intercostal vein, artery, nerve (VAN from most sup-inf.) *** MOST fractures occur immediately anterior to the costal angle --> the weakes part of the rib

56 y/o women with SOB, ankle edema, and mild hepatomegaly most likely has

Right sided heart failure

For improvement due to error- start with a

Root Cause Analysis (RCA) - systematically determine underlying system factors contributing to a error or series of negative incidents - bring together individuals from diff. departments and training to review an incident with the purpose of recommending changes to prevent a similar occurence * Consider a Cause and effect diagram using the terms: - ppl - processes - policy - methods - material - environmental factors

When phosphorylated, phospholamban dissociates from

SERCA and Ca uptake rates increase - Ca removed from sarcoplams, decreasing contractility of smooth muscle and leading to relaxation

Cardiac output

SV x HR

In the oral cavity as part of GI mucosal immunity what substance can be found in the mouth

Saliva! Contains - mucus - amylase - bicarbonate - lysozyme - RNAse - DNAse - IgA etc.. *** Sjogren Syndrome: inability to produce salive and tears because there may be an infection or lacrimal sac/salivary glands can lead to - dry eyes (xerophthalmic) or dry mouth (xerostomia)

Selenium is important as

Selenium-cysteine in a number (~20 enzymes) Ex. Oxidoreductases RDA= 0.055mg/d It can be found in: nuts, cereals, meat, mushrooms, fish and eggs Deficiency can be seen in HYPOthyroidism

Does the stomach have adventitia or serosa?

Serosa! - CT covered with mesothelium (AKA epithelium) - serosa is better than adventitia here bc the stomach should be able to move

Acute Abdominal Pain

Severity of the pain does NOT necessarily correlate with the severity of the underlying condition - any patient with abd pain of recent onset requires early and thorough evaluation and accurate diagnosis - abd pain that worsens with jolting movements, such as going down stairs (peitoneal pain)= peritonitis - pain may be referred to abdomen for pathologies outside the abdomen

Circulation through the primitive heart

Sinus venosuss through to the primitive atrium through the atrioventricular valve to the primitve ventricle to the bulbus cordis to the truncus arteriosus into the aortic sac

Compare the Laxative effects at Usual clinical dose of different types of laxatives

Softening of Feces (1-3days SLOW) can be done via: - Bulk forming laxative - Stool Softeners - Osmotic - Low dose laxatives (for softening of stool and evacuation of feces Soft or Semifluid Stool (6-8hrs MEDIUM) via - Stimulant laxatives Watery Evacuation (1-3hrs FAST) via: - Osmotic Laxatives (given at High dose for rapid evacuation of unformed feces from the colon)

Intercostal Nerves (** VAN in costal groove of rib)

Source: Ventral primary rami of spinal nerves T1-T11 Branches: Lateral and anterior cutaneous branches (to the skin) Motor: Intercostal muscles (internal and innermost), abd wall muscles (via T7-T11), muscles of the forearm and hanve (via T1) Sensory: skin of cheat and abd anterolaterally, skin of the medial side of the upper limb (via T1-T2)

Sources of VitE, Tocopherol

Sources: vegetable oils, oil seeds, wheat germ Deficiency: rare, but can occur in newborns who have to develop stores - otherwise, its typically due to poor absorption or chylomicron packaging - NON-toxic NOTE: anti-oxidants are touted as being beneficial, BUT most studies show little, if any, effect of taking large doses of anti-oxidants

What are two general forms of Sphingolipids

Sphingomyelins (a phospholipid) and glycolipids NOTE: - sphingosine can be found as a breakdown product of sphingomyelin - sphingomyelin has choline headgroup and its middle FA is attached by a stronger amide bond rather than an ester bond - ceramide is the basis structure for glycolipds (ceramide + sugar) - ceramide is also the basis for glycolipids) - cermides is also a breakdown intermediate

L colic flexure is AKA as the

Splenic flexure (associated with the spleen) - turn between the transverse colon to descending colon

Negative feedback for blood pressure control

Stimulus (change in BP) ---> receptor (baroreceptor- stretch receptors) --> control center (nucleus tractus solitarius (NTS) in Medulla (brain stem) --> effectors (heart and vessels- regulation of HR, SV, and TPR) --> response (restores BP towards normal)

Mucosal Protective Agents include

Sucralfate Misoprostol Bismuth subsalicylate

Pt with excruciatingly painful headache- then found unresponsive, autopsy shows Subarrachnoid Hemmorhage- most likely due to

Systemic Hypertension *** Subarachnoid Hemmorrhage is a common complication

T or F: sphingolipids are used in blood type groups

T! these differ in their glycolipid tree and have diff. enzyme that allow for transfer of diff sugars to the end Type O: has fruc Type A: has Gal-Nac and Fuc Type B: has Gal and Fuc

T or F: DHPR channel blockers will not interfere with contraction of skeletal muscle

TRUE!

T or F: The relative permeability to different ions is VERY IMPORTANT in influencing membrane potential

TRUE!

The absence/down-regulation of what protein can lead to increased susceptibility to UTIs

Tamm-Horsfall protein (THP) * which is part of the chemical defense of the GU it is only found in the GU made by uroepithelial cells - this protein binds to UPEC (uro-pathogenic E.coli) which is the MOST common cause of UTIs- this binding prevents it from binding to GU tract - so people with increased THP usually have more protection from UTIs - ppl with less THP may experience increased UTIs

3 distinct bands of smooth muscle that turn longitudinally in the LI are referred to as

Teniae Coli - begin at the appendix - terminate by merging together at the rectosigmoid junction - contract lengthwise to form haustra (or pockets that facilitate formation of fecal pelets)

Rectum is much like the colon except it LACKS

Teniae coli

MOST bile acid/bile salt absorption occurs at the

Terminal ileum - most typically of conjugated primary bile acids (bile salts) - this occurs using secondary active transport, with an apical sodium symporter ** if something occurs that requires a patient to have his/her terminal ileum resected, the persons enterohepatic circulation of bile acids will be severely compromised

Innervation of the Testes

Testes are Visceral Organs and therefore receive autonomic innervation Sympathetic (fight or flight) - paravertebral ganglia --> lesser splanchnic nerve --> prevertebral (PRE-aortic) ganglia - testicular plexus of nerves is involved - wraps around the testicular a. to reach the testis, epididymis and ductus deferens - promotes ejaculuation: propels semen along the duct system - increases glandular secretions Parasympathetic Innervation (rest and digest) - erectile tissues of the penis and prostate gland receive parasympathetic innervation from the pelvic splanchnic nerves - promotes sexual arousal

General structure of the Major Salivary Glands

The paortid, submandibular and sublingual glands are structurally very similar to one another, although they produce various secretions - Each of these glands has a secretory portion (indicated by the acinus above) and a ductal portion * use the analog of a bunch of grapes to assist in this understanding- the grape is the secretory portion and the stalks are the ductal portions Acinus collectively secrete fluid (mucus and/or serous) --> intercalated ducts --> striated ducts (remember intercalated and striated ducts are part of the intralobular ductal system) --> interlobular duct --> out through main duct

3 Types of Ribs based on their articulation with the sternum

True ribs (1-7): connect to the sternum via costal cartilages False ribs (8-10): connect to the cartilages of the ribs directly ABOVE them (ex. they connect to costal cartilage of 7th rib) Floating ribs (11th and 12th): NO connection with sternum; terminate in the post abdominal muscles

T or F: the muscularis mucosae is absent in the upper part of the esophagus

True!

T or F: Visceral pleura is NOT part of the thoracic wall layers

True! * only the parietal pleura and pleural space are * pleural space is where the thoracic wall ends

T or F: Lactose intolerance is the normal state

True! Lactose tolerance after age of 3 is actually a mutation

From ceramide to make glycosphingolipids you can commonly use

UTP to tag (ex. UDP-galactose or UDP-glucose) or UDP to make Globoside using CMP as tag to attach N-acetylneuraminic acid --> ganglioside * Gangliosides contain sialic acid (N-acetyl neuraminic acid) * Globosides are linear sugar chains on ceramide

Gastric Injury Ex:

Ulcer - this is when the damaging forces are increased or there are impaired defenses ex damaging forces: - H. pylori infection - NSAID - Aspirin - Cigarettes, Alcohol, Gastric hyperacidity, duodenal- gastric reflux can lead to - ischemia, shock, delayed gastric emptying, host factors ultimately leading to an ulcer or some type of gastric injury

Development of the Anal Canal

Upper anal canal develops from the hindgut ---- separated by pectinate line------ Lower anal canal develops from the proctodeum *** this dual embryonic origin of the anal canal means variation in epithelium, blood supply and lymphatic drainage ** junction between upper and lower anal canals marked by pectinate line which marks the site of former anal membrane

Possible sxs of carcinoma in uterurs, ovaries, and labium majus

Uterine: abd vaginal bleeding and pelvic or abd pain Ovarian: fatigue, menstrual changes, pelvic or abd pain Labium majus: gradual change, lasting itch, pain or soreness, lump or swelling

As the stomach (foregut) rotates the LESSER omentum is formed from the modification of the

VENTRAL mesentery NOTE: Growth of the liver results in splitting of the VENTRAL mesentery into the lesser omentum and the falciform ligament

Beta-glucoamylase (alpha- and beta-glucosidase) and Trehalase are

VERY MINOR enzymes - Beta-glucoamylase (alpha- and beta-glucosidase) is secreted by all of the small intestine (enterocyte) - Trehalase is secreted by the duodenum (enterocyte

Class IV antiarrhythmic drugs

Verapamil Diltiazem Nicardipine Nifedipine Amlodipine ** These are all Ca2+ channel blockers

What does supracolic refer to?

Visceral structures below the diaphragm and above the transverse mesocolon * remember transverse mesocolon separates infracolic from supracolic

Which has neuropsychiatric symptoms Folate deficiency or VitB12, Cobalamin

Vitamin B12 Cobalamin is the one that has neuropsychiatric symptoms

The initial (oral) stage of swallowing is

Voluntary - everything beyond this is involuntary - the process is under control of the swallowing center (in the medulla and lower pons) - it is stimulated by touch receptors in the oropharynx (very back of oral cavity) - 100% skeletal muscle-mediated in oral cavity, pharynx and upper 1/3 of esophagus- there is NO enteric nervous system here, just well-controlled motor unites - Upper Esophageal Sphincter (UES) also controlled in this way- gets opened up as part of skeletal m. otherwise it is closed

Rapid growth of the liver results in physiological hernitation of the migut in what week?

Week 6 - The intestinal loop rotates 90 degrees anticlockwise around the Superior Mesenteric Artery (SMA) - Midgut enlarges jejunal-ileal loops are formed ----- During the 10th week the intestines RETURN to abd. cavity - 180 degree anticlockwide rotation occurs - Results in definitive pattern/arrangement of midgut achieved **** The intestines have undergone a total of 270 anti-clockwise rotation during development - As intestines return to the abd. cavity, vitelline duct is obliterated and loses its connection to the intestines

Ectopic Pancreatic Tissue

With rotations, parts of the pancreatic tissue can break off and get lost They can be found in areas ranging from distal esophagus to tip of primary intestinal loop - Most frequently in duodenum or stomach mucosa (bc these are closest to where it normally originates) - Small proportion of Meckels Diverticula contain pancreatic tissue

Disorders of salivation resulting in

Xerostomia (dry mouth) - often mentioned in context of certain drugs

Inferior Thoracic Aperture (ITA) Boundaries

Xiphisternal Joint 7th-10th Costal cartilages (R&L) 11th & 12th ribs T12 vertebra *** ITA is covered by the diaphragm and is mobile

What kind of fracture is commonly seen in poor CPR procedure or Contact Sports?

Xiphoid Process Fracture - dislocation of the xiphisternal joint - Injury compromises the diaphragm: bc the xiphisternal joint forms the anterior attachment of the diaphragm - Broken pieces can puncture the heart or the liver

Enzymes that are made in an inactive form then activated under specific physiological conditions are referred to as

Zymogens - typically these are enzymes that could cause harm if not controlled - inactive form can be stockpiled without damage to the cell or tissues (have an N-terminus that inhibits enzymes from working) - ACTIVE forms can cause damage, such as erosion of tissue (ex. GERD) Many digestive enzymes are produced as Zymogens Such as: - Pepsin - Trypsin - Chymotrypsin - Elastase - Lipases - Carboxypeptidases - Phospholipase A2 ------- Ex of cascade of activation: Trypsinogen has its "N-terminus" tail chopped off via enterokinase "AKA enteropeptidase"--> its activated to Trypsin * Trypsin can activate ANY of the proteases made as zymogens by direct clevage of the N'terminus Ex. chymotrypsinogen --> chymotrypsin Trypsinogen --> trypsin Proelastase --> elastase

As flow rates increase _____ falls, and ____ rises

[Na+] falls [H+] rises ** pH drops (gets more acidic)

The minor duodenal papilla (AKA the lesser duodenal papilla) is where the ___ opens

accessory pancreatic duct - it releases pancreatic juices ONLY - it is located apprx. 2cm superior to the major duodenal papilla * minor and major duodenal papilla are both found in the 2nd part of the duodenum

The stomach is an expanded part of the GI tract where food can

accumulate and prepared for mechanical breakdown and chemical digestion - it is an intraperitoneal J-shaped organ

Increase in tone=

an increase in vessel resistance caused by an increase in symp innervation, aka increased symp drive to the vessel

cholesterol is the precursor of

bile acids and bile salts

Stable angina pectoris

chest pain - lasts 2-5 min (<20 min) - alleviated with rest or nitroglycerine

decreased blood volume leads to decreased driving pressure and thus

decreased venous retunr

increased venous compliance (decreasing vessel tone) --> venous reservois held in veins-->

decreased venous return

In muscle, LPL is ____ by insulin

downregulated! (in fed state) - In fasted state, when insulin is low: the higher LPL in muscle helps provide fatty acids for energy to the muscle

When contained exudate is pure pus in the gallbladder, the condition is referred to

empyema of gallbladder

Which cardiovascular disorder is most common in US?

hypertension

Right Heart failure leads to a backup of fluid in systemic veins and capillaires ( back up of fluid from heart to venous system and capillary beds i.e. increased CVP) which leads to

increased fluid in capillary beds --> increased systemic capillary hydrostatic pressure --> increased filtration and reduced reabsorption --> peripheral edema

Peritonitis

infection can occur if gas, fecal matter or bacteria enter the peritoneal cavity which would result in inflammation of the peritoneum

Microscopic change that is characteristic of acute MI

loss of cardiomyocyte nuclei

incidence=

number of new cases / number at risk to be a new case

The Omental Foramen is an

opening that provides a direct communication between the greater and lesser sacs and is AKA epiploic foramen and foramen of winslow

What pathological conditions are characteristic of L sided heart failure

pulmonary edema and pleural effusion

Cystic Fibrosis is due to mutations that

result in blockage of channels CFTR Decreased chloride and water transport out of cells leading to thicker secretions - higher concentrations of zymogens in pancreatic secretions increases freq. of auto-activation of enzymes - thicker secretions may cause blockage of pancreatic duct - activated zymogens erode duct tissues and pancreas (pancreatitis) *** Pancreatic trypsin increases in blood due to destruction of pancreas

Risk factors for ischemic heart disease

smoking, hypertension, diabetes mellitus, obesity, sedentary life style

Glucose and Galactose use the

sodium-linked symporter, SGLT-1

The primordial tests function in

sperm production

Abdominal angiography can be used to view

the vessels of the abdomen with the use of contrast and the blood supply in the bowel

Cerebral blood glow is almost entirely controlled by local factores bc

there is limitied SNS control bc very few alpha-1 receptors present Metabolic control: - active hyperemia- hypercapnia (high CO2) - whereas reduced arterial COA (ex. hyperventialtaion)--> vasoconstriction and dizziness ** Basila artery and internal carotids combine to form the Circle of Willis which helps maintain blood flow to the brain *** as CO2 levels in cerebral blood increase, flow to the brain increases due to vasodilation via active hyperemia ** symp innervation reduces flow to the brain via vasoconstriction but only seen at higher arterial pressure

Anterior and posterior intercostal VEINS anastomose as

they approach the vertebral coulmn