UWorld Questions

Atropine

Competitive antagonist to the muscarinic receptor

Why would someone put their emotions from a person to the past to a person in the present?

this is a defense mechanism called transference occurs due to the unconscious shifting of emotions

SnRNA

transcribed by RNA polymerase II

Why should you never give isoniazied alone to a patient

will cause there to be a rapid change in antibiotic resistance two mechanisms 1. decrease in bacterial expression of the catalase-peroxidase enzyme that is neefed for isoniazid activation 2. modification of the protein target binding site for isoniazid commonly use: isoniazid & rifampin with streptomycin, ethambutol and pyrazinamide

MEN2

will have pheochromocytoma, MEDULLARY THROID CANCER and either parathyroid hyperplasia (2A) or marfanoid habitus and mucosal neuroma (2B) pt will have nests or sheets of polygonal or spindle shaped cells with extracellular amyloid (these are from calcitonin secreted by the neoplastic C cells and stain with Congo Red

Amiodarone has what effects?

1) has some sodium channel blocking ability - prolong the QRS 2) inhibits the slow L type Ca channels that depolarize the SA and AV node -- decrease sinus rate and prolong PR Interval

CA 125

Ovarian

What hormone promotes the development of acne?

androgens

What will prolong the QT interval

prolonged K+ channel inhibition

What kind of fracture would cause median n. lose

supracondylar humerous fracture

What causes nonexertional heat stroke?

*anticholinergics - amtriptyline, scopalamine (inhibit diaphoresis and heat dissapation) *sympathomimetics -amphetamines, cocaine (impair peripheral vasodilation, limiting heat transfer) *dopamine antagonists - chlropromazine, haloperidol (disrupt hypothalmaic regulation) *diuretics/beta blockers (limit the cardiac response to heat stroke by reducing blood volume or HR so that the blood cannot go to the skin

Which types of malaria have a dormant phase?

P ovale and P vivax these have a hypnozoite -- can reactive several months after returning

Milrinone

PDE3 inhibitor increases intracellular calcium influx - increases cardiac contractility (positive ionotropy) increases Ca uptake in smooth muscle SR -- leads to vasodilation (decreases preload)

Pathogenesis of the annular pancreas?

abnormal migration of the ventral pancreatic bud

What controls flexion of the thigh?

accomplished by the psoas, iliacus, and sartorius muscles innervated by the lumbar plexus and femoral n.

Mitochondrial Myopathies

are rare disorders often presenting with myopathy, lactic acidosis, and CNS disease secondary to failure of oxidative phosphorylation. biopsy shows ragged red fibers on Gomori trichrome stain. MELAS is one such example. will only be passed from mothers, not from the male

Obturator n.

arrises from L2-L4 only major nerve that arrises from the obturator canal

What are the path findings of central retinal artery occlusion?

cherry red macular with a pale retina

Human Chorionic gonadotropin

choriocarcinoma germ cell tumors

What happens when the testes are removed?

decreased androgen synthesis-- leads to a hypgonadal state decreased lean body weight, increased total weight and subcutaneous fat decreased prostate volume

Caudate nucleus, putamen, and globus pallidas

extrapyramidal motor system - regulates voluntary and involunatary motor function

Which drugs require protein mediated transport into the bacterial cell for action?

flouroquinolones, macrolides, and aminoglycosides

Where is the substantia nigra located?

in the midbrain

Effect of azoles of CYP450

increase serum concentration of drugs metabolized by liver P450 -- means there will be increased toxicitiy (warfarin, cyclosporine, tacrolimus, and oral hypoglycemics should be avoided) inducers - rifampin, phenytoin, carbamazapine, phenobarbital MOA: inhibit the demethylation of lanosterol into ergosterol in fungal cells (suppress synthesis of ergosterol)

Radial Nerve injury

injury to the proximal n as it crosses the posterior humerous spare the triceps brachii -- d/t fibers leaving earlier

What happens in a patient with reduced renal perfusion?

lower GFR so then the RAAS system is induced -- leads to production of angiotensin II which is a vasoconstrictor to cause systemic HTN and preferentially will constrict the efferent arteriole

What does it mean to be passively absorbed

means there will not be a clear cut point (like the Tmax) because it is just reabsorbed through passive diffusion

Color variation in melanoma

melanocyte regression due to cytotoxic T cell destruction by recognition of tumor antigens pembrolizumab -- PD-1 inhibitor could also cause this color change

What will prolong the PR interval?

prolong via Ca2+ channel inhibition or sympathetic blockade

False negative TST could be due to what?

recent infection (because it takes ~8 weeks for cell mediated response to form) immunocompromised Improper injection technique natural waning of immunity to latent infection

What does the uterus look like in proliferative phase?

straight, short endometrial glands with compact stroma

What happens with large loads of K+

the majority of K+ is reabsorbed by the time we get to the end of the PCT but excretion is controlled in the DCT * alpha cells - H+/K+ ATPase that will help to reabsob K in hypokalemic states *principle cells - increase K+ secretion d/t K excretion in the apical membrane *hyperkalemia -- aldosterone to be released which increase K+ secretion

What is projection

this involves misattributing one's own unacceptable feelings to another person

Which virus is dependent on HBV replication?

HBV D! does not have its own machinery

CA 19-9

Pancreatic

REM parasomnia

REM sleep behavior disorder and nightmare disorder more prominent sleep pattern during the second half of the night EEG resembles wakefulness - alpha and beta waves, with an occasional sawtooth wave

Celiac Disease

TTGA positive villous atrophy in the small intestine - less absoption of fat soluble vitamins --> Vitamin D deficiency will see rise in PTH --> induces the release of

Polyarteritis nodosa

What vasculitis is characterized by systemic vasculitis in small to medium- size vessels (except the lung); affecting young males; 30% HBsAg-positive; P-ANCA and autoantibodies against myeloperoxidase?

AFP

associated with HCC (high in diagnosis and screen for recurrence) and germ cell tumors d/t production by the fetal yolk sac and liver during gestation

What does the insula do?

consciousness and emotion w/ limbic system autonomic control and awareness of visceral sensations

What does the uterus look like in luteal phase?

dilated, coiled endometrial glands and vascularized stroma. note - this is what it would look like with an ectopic preganancy d/t progesterone as it prepares for implant

Subacute granulomatous (de Quervain) thyroditis path

disruption of the follicules and mixed cellular infiltrate with occasional multinucleate giant cells

Why do women get gallstones in pregnancy

estrogen -- increases cholesterol synthesis by upregulating HMG-CoA reductase (bile becomes supersaturated with cholesterol) progesterone reduces bil acid secretion and slows gallbladder emptying

What is the major side effect of hydroxychloroquine?

irreversible retinopathy need to have regular eye exams

Isoproterenol

nonselective beta agonist -- stimulates B2 and B1 receptors

What are the classic characteristics of diabetic diarrhea

painless, secretory-like diarrhea that persists with fasting (nocturnal diarrhea)

Graves disease

path: thyroid follicular epithelium is tall and crowded with hyperactive reabsorption causing scalloping around the edges of the colloid

Acne vulgarus

proliferation of lipid-utlizing bacteria within pilosebaceous follicles usually propionibacterium acnes *anaerobic diphtheroid that is part of the normal skin flora pathogenesis: follicular epidermal hyperproliferation, excessive sebum production, inflammation and infection EGFR inhibitors, lithium, and methyltestosterone could all cause this

What will prolong the QRS duration?

prolonged via Na+ channel inhibition

TST test

type 4 HS reaction if no reaction then could be due to T cell anergy - this is an impaired lymphocyte response *increases the risk of severe disseminated TB

Carotid message mechanism?

use in paroxysmal supraventricular tachycaria -- most often due to reentrant impulse traveling between the slow and rapidly conducting segments of the AV node this is a vagal manuvere - meaning it increases vagal parasympathetic tone and SLOWS conduction through the AV node and prolongs the AV node refractory period

Methylmalonic acidemia

AT organic acidemia - completely or partial deficiency of enzyme methylmalonyl CoA mutase

What disease has defective tyrosinase?

Albinism melanocytes synthesize melanin from tyrosine using this molecule

Patient with decompensated heart failure and copious pink, amorphous material on cardiac bx.

Amyloid cardiomyopathy - extracellular deposition of fibrils of misfolded amyloid restrictive cardiomyopathy with uniformily thick walls, imapired diastolic relaxation. LV is normal or decreased and increased LV filling pressure causes reduced cardiac output elevated LV pressure is transmitted backward --> left atrial dilation, increased pulmonary arterial pressure and progressive right sided HF

What makes the FFA and glycerol in the fasting state?

Hormone sensitive lipase

What does MEN2A present with

Medullary thyroid cancer Phemochromocytoma primary hyperparathyroidism

How to calculate the chance give AR disease and carrying the gene.

P(affected child) =1/4 x P(carrier mother) x P(carrier father)

Patient with three month history of weight loss, abdominal pain and fatigue developed cardiovascular collapse during a medical procedure.

Suggests chronic adrenal insufficiency complicated by acute adrenal crisis Patient had findings of skin hyperpigmentation -- suggests a chronic adrenal insufficiency which led to increased ACTH

What is palmitic acid used for?

This is the first fatty acid produced from actyl CoA during lipogenesis in the fed state

What is the histology of mesothelioma?

cuboidal or flatted cells (epithelium-like) or spindle cells (stromal like) will stain positive for cytokeratins and many will also stain positive for calretinin. EM will show polygonal tumor cells with numerous, long slender microvilli and abundant tonofilaments

Mullerian aplasia has what characteristics?

defective development or congential abscense of an organ or tissue - they have variable uterine development and no upper vagina. will not be able to menstrate because the uterus is missing, but will have normal secondary characteristics because of the presense of ovaries.

Pathology of Paget disease of bone

disorganized lamellar bone in a mosaic pattern - normal calcium and phosphate

What is the main side effect of daptomycin?

disrupts the bacterial membrane by creating a transmembrane channel and causing intraceullar ion leakage causes myopathy and rhabdomyolysis

How does a large blood transfusion cause hypocalcemia?

donated blood is typicall mixed with solutions contraining citrate --> chelate calcium in the plasma leading to hypocalcemia not rhabdo can also cause this, but this would be a delayed finding (24-72 hours after trauma)

Why does the blood oxygen content slightly drop when leaving the pulmonary vasculature?

due to mixing of deoxygenated blood with oxygenated blood from the pulmonary veins

Wiskott aldrich syndrome

eczema, recurrent infections and thrombocytopenia Z-linked recessive -- cytoskeleton proteins Deficiency in B cell - pyogenic infeactions and T-cells with opportunitis infections - will see severe recurrent infections

Anterior compartment of the leg anatomy

foot extensor muscles, anterior tibial artery and deep peroneal (fibular) nerve these will be damaged by anterior acute compartment syndrome

How does vancomycin work?

glycopeptide that bind directly to the D-alanine-D alanine residues to prevent the incorporation of new subunits in the wall

How does latanoprost help in glaucoma?

increase outflow of aqueous humor due to decreased collagen content in the uveoscleral outflow pathway SE: increase pigmentation in the iris and eyelashes

What immune factor is involved in antiviral therapy

interferon alpha

Patient is given acetylcholine during an exercise stress test. What is the effect of that.

leads to effects on the vascular endothelium this is mediated by changes in acetylcholine, bradykinin, serotonin, substance P and shear forces. stimuli activate specific membrane receptors present on the endothelial cells --> increase in cytosolic calcium levels -- > activation of endothelial nitric oxide synthase which synthesizes nitric oxide from arginine, NADPH and O2. NO then diffuses into the adjacent smooth muscle cells and activates guanyly cyclase -- increases formation of cGMP. high levels of cGMP activate protein kinase G -- causes a reduction in cytosolic calcium levels and relaxation of vascular smooth muscle cells arginine availability is dependent on exogeneous food intake, endogeneous synthesis, intracellular storage and degredation and the presense of asymmetrical dimethylarginine

Porphyria Cutanea Tarda

most common disorder of prophyrin uroporphyrinogen decarboxylase deficiency -- inherited or acquired (alcohol, smoking, halogenated hydrocarbons, hepatitis C, HIV) sxs: photosentitivity with vesicle blister formation on sun exposed areas, edema, pruritis, pain and erythema

Post-streptococcal glomerulonephritis

nephritic syndrome ag-ab immune complex (T3 HS) granular depositis of IgG, IgM, and C3 on GBM and mesangium -- starry sky subepithelial humbs on GBM

Pathology of hyperparathyroid in bone

osteoporosis - note hyperthyroidism results in thinning of the bone more pronounced in the cortical (compact) bone of the appendicular skeleton) --> subperiosteal erosions compared to osteoporosis which affects the trabecular bone

What is the single strongest factor predictive of completed suicide?

past suicide attempt.

What causes Meckel's Diverticulum?

persistence of the vitelline duct this would present with painless lower GI bleeding without emesis

Where will aspiration PNA usually occur in a supine position?

posterior segments of the upper lobes and the superior segments of the lower lobes

Patient with ring enhancing lesions. Negative for toxo and has HIV.

primary CNS lymphoma diffuse, large cell non-hodgkin lymphoma of B cell origin that is a late complication of HIV EBV is identified in most cases

Patient with rapidly spreading, pruiritic rash with erythematous papules and excoriations on the extremities.

scabies sarcoptes scabiei mite -- burrows into the skin and spreads through person to person contact intensely pruritic rash in the flexor surfaces of the wrist, lacteral surfaces of the fingers and the finger web delayed T4 hypersentitivity that makes it worse at night

What nerves are involved in cauda equina syndrome?

sciatic, pedundal, and pelvic splanchnics

What is the normal response to secretin

secretin is secreted in response to acid and fat in the small intestine -- normall increases pancreatic bicarbonate secretion and inhibits the release of gastrin from normal G cells in ZES - this will paradoxically increase gastrin release due to abnormal cAMP secretion

CNIII palsy can present as what?

somatic: innervates the inferior, superior, and medial rectus; inferior obliques and the levator plpebrae muscles ptosis due to paralysis of the levator palpebrae and the unopposed action of the LR and SO lead to a down and out gaze parasympathetics: innervate the iris sphincter and ciliary muscle - fixed, dilated pupil and loss of accomidation

Renal Cell Carcinoma sxs and path

sxs: gross painless hematuria in older adults are a sign of urinary tracts cancer until proven otherwise path: rounded/polygonal cells with abundant clear cytoplasm. proximal tubular epithelial cells and have intracellular glycogen and lipids

What type of vaccine do we give for tetanus?

tetanus toxoid vaccine -- stimulates a humoral antibody response therefore these circulating antibodies neutralize the bacterial products *note the neurotoxin is tetanospasmin

Patient refuses to recieve medical information and expresses a clear preference with capacity.

this decision should be respected. Patient autonomy means that you should do what he says

DNA polymerase III

this has 5' to 3' synthesis and proofreads with 3' to 5' exonuclease

What occurs when there is needle-shaped clefts in the arterioles of the kidney?

typically due to atheroemolization -- after coronary angiopathy will see sequelae of atheroemboli in other organs and tissues

nonbacterial thrombotic endocarditis

valvular endothelial injury caused by circulating inflammatory cytokines and then platelets are deposited because of they hypercoagulable state -- commonly associated with advance malignancy (esp. mucinous adenocarcinoma) and Libman Sacks endocarditis

Where is water permeable in the nephron? Where is it not permeable? where is urine most dilute?

descending limb of loop of henle -- free water is drawn out and the renal interstitium and the tubular fluid becomes hypertonic thick and think ascending limb is impermeable to water and elevtroles are absorbed leading to hypotonic urine DCT is impermeable to water, so the tubular fluid remains hypotonic so the fluid in the distal tubules is most dilute when ADH is not present, the collecting duct and create very dilute urine due to continued solute reabsorption and no water reabsorption

Pernicious Anemia path

destruction of pariteal cells -- predominately in the upper glandular layer of the gastric body and fundus. these are located in the upper glandular layer

How would a patient with Friedrich Ataxia present?

destruction of the dorsal columns, dorsal root ganglion (loss of proprioception and vibration sense), lateral corticospinal tract (spastic weakness), and spinocerebrallar tracts (ataxia) could also have high arches (pes cavus), kyphoscoliosis, and hypertrophic cardiomyopathy

Oocyte development

develop until the fifth month of gestation -- then they are arrested in prophase of meiosis I. menstrual cycle induces the primary oocyte to resume differentiation -- arrested in metaphase II before differentiation

What is the difference between overflow incontinence and detrussor hypercontractility?

difference is usually seen in the post void residual overflow incontinence will have a high post void residual wheras hyperreflexia is lower

Patient with widespread axonal swelling, predominantly at the gray-white junction. immunohistochemical stain with alpha-synuclein and APP in axons. After high speed motorcylcle collision. What is the dx and cause?

diffuse axonal injury. transfer of force results in shearing of the white matter tracts or induces secondary biochemical changes leading to degeneration of the axonal cytoskeleton with subsequent axon breakage. when normal axonal transport is inhibited --> accumulation of axonally transported proteins with axonal swellings at the point of injury widespread axonal swelling, more pronounced at the gray-white matter junction

What happens in acute PE?

dilation of the right ventricle cavity

Syncopal episode with recent hospitalization 2 weeks ago for a fib with RVR and a new medication was started. Patient now with constipation and AV block. What medication? Why not others.

diltiazem - CCB block the L-type calcium channels, decrease the phase 0 depolarization and conduction velocity in the SA and AV nodes this slows the sinus rate and conduction through the AV node causing bradycardia and varying degrees of AV block negative inotropic effect and are contraindicated in patients with congestive heart failure SE: constipation

How do alcohol based disinfectants kill bacteria, viruses and fungi?

dissolves their lipid bilayer membranes and leads to denaturation of proteins. Nonenveloped viruses are less sensitive because they do not have a bilayer envelop.

Patient with migraine give metoclopromide and diphenhydramine. Why diphenhydramine?

dopamine receptor blockage (metocloprmide, prochlorperazie) can be used to abort headaches by antagonizing D2 receptors in the midbrain and striatum can also lead to excess cholinergic activity that manifests as significant extrpyramidial symptoms -- acute dystonic reaction. diphenhydramine can prevent this due to its anticholinergic activity

Cri du Cat syndrome

due to 5p deleations usually present with round face, catlike cry, and microcephaly

Pemphigus Vulgarius

due to autoantibodies directed against desmosomal proteins, bx will show intraepithelial cleavage with detached keritinocytes -- esinophilic inflammatory infiltrate

What causes crescent formation in rapidly progressive glomerulophritis?

due to firbrin and macrophages

What allows for conversion of Corynebacterium diphtheriae to become toxogenic?

due to infection with a lysogenic bacteriophage -- corynephage beta this phage inserts the tox gene into the diphtheriae genome -- results in bacterial expression of diphtheria AB toxin this will then irreversibly half protein synthesis due to ADP-robosylation of elongation factor 2 and cause severe local pseudomembranous pharyngitis and systemic (myocarditis, neuritis) effects

Aortic Regurgitation murmur

early diastolic murmur-high pitched "blowing" - best heard at the left sternal border bounding femoarl and carotid pulses by abrupt distension and quick collapse are water hammer pulses (wide pulse pressure) can also see head bobbing with the carotid pulsations

What is the presentation of homocystinuria?

ectopic lens, intellectual disability, Marfanoid habitus, thrombosis and atherosclerosis

What is the effect of hypothyroidism on serum lipids? How does this happen?

elevate total cholesterol and LDL cholesterol. This is due to decreased LDL receptor expression. may also decrease LDL receptor activity and biliary excretion of cholesterol. hypertriglyceridemia -- due to decreased expression of lipoprotein lipase

What would cause dilation of the coronary sinus in an otherwise healthy adult?

elevated right-sided heart pressure secondary to pulmonary HTN. this is because the coronary sinus drains into the right atrium, and will dilate in response to elevated right heart pressures. hypertrophic cardiomyopathy is instead due to asymmetric sepatal hypertropy with or without left venticular flow and will not cause coronary sinus dilation without biventricular heart failure

Where does focal seizures originate from with impaired awareness?

emporal lobe epilepsy. usually preceeded by a distinctive aura (uneasy epigastric sensation, unpleasant olfactory hallucinations) that localizes to the mesial temporal lobe - hippocampus, amygdala, parahippocampal gyrus. usually due to underlying hippocampal sclerosis due to childhood febrile seizures

Patient with recurrent episodes of chest discomfort, spontaneously resolve in 10-15 minutes. What causes it?

endothelial cell dysfunction and autonomic imbalance that leads to intermittent coronary vasospasm and MI smoking is a strong RG excessive vagal tone - acetylcholine will cause and ergot alkaloise activate 5-HT to cause

Patient with a history of solid food dysphagia with esophagia food impaction. What is the dx?

eosinophilic esophagitis - Th2 cell-mediated disorder -- release chemokines (IL-13 and IL-5) that stimulate eosinophilic recruitment to the esophageal mucosa commonly in males with a history of other atopic conditions, will have intermittent solid food dysphagia endoscopically: circular, ringlike indentations; linear furrowing and scattered, small whitish papules (eosinophilic microabscesses). bx will show eosinophilic muscosal infiltration

What are portacaval anastomoses?

esophageal varices: left gastric vein -- esophageal vein anorectal varices: superior rectal vein -- middle inferior rectal veins Caput medusa: paraumbilical veins -- superior and inferior epigastric veins

What happens at the initiation of labor in the uterus?

estrogen --> upregulation of connexins to allow for myometrial excitability also increases expression of utertonic recpetors (oxytocin) to mediate calcium transport through the ligand activated calcium channels

What is the pathogenesis of the immune development in mycobacterium tuberculosis?

eventually IL-12 differentiates naive CD4 cells into T helper cells (Th1) --> secrete interferon gamma which activates macrophages --> form granulomas

What happens in DIC?

excessive activation of the coagulation cascade generation of thrombin and cross linked fibrin clots -- activate fibrinolysis to clear the clots and make plasmin to degrade the products

Patient with skeletal pain, deformity (bowing of the legs) and focal warmth has Paget disease of bone.

excessive and disordered bone formation, bone is weakened. increased blood flow in pagetic lesions can be apparent as local warmth or bruits and can lead to high output heart failure. elevated Alk phos. calcium, phosphorus, and parathyroid hormone levels. x rays will show thickening of cortical and trabecular bone and bone deformitis

Patient taking Niacin and causes facial flushing. What should he be given to prevent this and why?

facial flushing is due to prostaglandins -- should be given niacin

Incidence is staying the same, but the prevalence is rising in a population. What causes this?

factors the prolong disease duration and increase the disease prevalence -- improved quality of care can lower the mortality rate.

Patient with abdominal discomfort and loose stools. all test are normal. What is the best next step for assessing for impaired nutrient absorption?

fats are typically the earliest and most severely affected nutrient in generalized malabsorption and testing for fat malabsorption is the most sensitive strategy for screening for malabsorption disorders. sudan II stain will quickly and easily identify unabsorbed fat

What would you expect to happen to RAAS when give ACE and ARB?

feedback will cause and increase in RAAS levels *compare to beta blockers and clonidine that will decrease renin levels

Patient at 18 weeks gestation who is found to have fetal ultrasound with unilateral hydronephrosis. Where is the obstruction most likely to occur?

fetal hydronephrosis is detected in the second trimers -- usually transient as the fetal renal pelvis has high compliance and can accomodate large volumes of urine most commonly due to narrowing or kinking of the proximal ureter at the ureteropelvic junction if not dx prenatally, they will present with a palpable abdominal mass with a large kidney

What is the blood gas of someone at high altitude?

fewer O2 molecules --> hypoxemia with a marked reduction in the arterial partial pressure of O2. triggers the chemoreceptors in the carotid bodies --> ventilation --> increased exhalation of CO2 --> respiratory alkalosis. kidney compensate by increasing bicarb excretion to decrease serum HCO3- and normalize pH

How is the clearance of phosphate regulated?

fibroblast growth factor 23 secreted by osteocytes in response to hyperphosphatemia FSF23 1) suppresses 1-hydroxylase -- decreased intestinal phophage absorption and decreased renal phosphate reabsroption 2) downregulates sodium/phosphate cotransporter IIa in the renal tubules

Scar tissue after an MI is made up of what? what is the process?

final stage of MI healing is firbosis and due to increased type 1 collagen deposition. this is made up of type 1 collagen. initially the scar will be made of granulation tissue with type 3 collagen, but this is replaced as the infarct matures

Patient with chronic aortic regurgitation due to infective endocarditis. How does the patient maintain cardiac output

first -- left ventricular dilation caused by an increase in the left ventricular EDV (volume overloads) triggers eccentric hypertrophy --> involves ventricular wall legthening due to the addition of myocardial contractile fibers in series --> increase in the stroke volume that is able to maintain CO overall this is maladaptive -- progressive LV dilation leads to overwhelming wall stress with decreased stroke volume and eventual left ventricular failure

pulsus paradoxus pathology

fluid accumulation in the pericardium causes limitation of right ventricular expansion that is exacerbated druing inspiration by the increase in venous return -- blowing of the intraventricular septum toward the left ventcile -- decreases LC end-distolic volume and stroke volume

Patient with metastatic prostate cancer and poor response to long acting GnRH agonist. Adding flutamide in this patient. How dose it work?

flutamide is a nonsteroid agent that acts as a competitive testosterone receptor inhibitor. prevention of androgen-receptor binding blocks the stimulator effect of androgens on the primary tumor and metastases and leads to a reduction in their size -- improving bone pain and urinary obstruction.

Young patient with a central, gray-white depressed stellate scar from which fibrous septae radiate to the periphery.

focal nodular hyperplasia commonly occurs in young women small, solitary pal nodules composed of cords of normal appearing hepatocytes with a central stellate scar

What type of cancer is most likely to present with a persistent, fluctuating lymphadenopathy that may be associated with an unrelated pharyngitis?

follicular lymphoma indolent NHL waxing and waning clinical course - painless lymph node enlargement cleaved and noncleaved follicular center cells in a nodular pattern t(14:18) translocation

What is the pathology behind radiation induced lung injury?

following thoracic irritation and ionizing radiation causes direct DNA damage (ROS and nitrogen that damages DNA) damage will affect the alveolar-capillary barrier (pneumocytes and vascular endotherlial cells) --> inflammatory response with IL-1 and TNF-alpha and growth factors TGF-beta and PDGF acute: exudative alvolitis with sloughing of penumocytes and vascular endothelial cells, alveolar/interstial edema and hyaline membrane formation delayed: radiation fibrosis - due to TgF-beta forming dense firbosis bands and predispose to chronic infections

Salmonella diarrhea presentation

foodborn gastroenteritis - consumption of contaminated poultry products those on acid suppression require a smaller infectious dose and are at greater risk watery diarrhea complications are long bone osteomyeolitis due to spread through the blood stream

Where are beta 1 receptors located?

found in cardiac tissue and on renal juxtaglomerular cells not found in vascular smooth muscle

What antihypertensive medication is associated with ototoxicity?

furosemide this also causes hypokalemia, hypomagnesemia and hypocalcemia

MOA of entanercept

fusion protein with domains derived from the Fc portion of IgG1 and TNF receptor 2 functions as a decoy receptor for TNF-alpha similar to monoclonal antibodies inflizimab and adalimumab must do a TST

Zollinger-Ellison syndrome

gastrin-secreting tumors - malignant and are in the small intestine or pancreas peptic ulcers, heartburn and diarrhea seeing a distal duodenal ulcer is usually ZES

What is a complication of Shigella?

generalized seizures due to systemic absorption of shigella enterotoxins usually transmitted in day care centers

Graph that shows increasing hormone levels in control subjects leading up to meal time, with a significant drop after food intake. Which hormone is this?

ghrelin produced in the stomach in response to fasting -- surge leading up to meals and fall after eating. stimulates appetite and promotes weight gain caloric restriction and falling fat stores lead to increased ghrelin levels -- which limits weight loss from dietary modification along. bariatric procedures -- removes a portion of the stomach and loose many ghrelin-secreting cells leading to lower ghrelin levels and less stimulation of appetite in response to fasting

Patient is exposed to radioactive iodide, how would you decrease the ultimate uptake and exposure?

give potassium iodide. competitively inhibits radioactive I131 from entering the thyroid follicular cells - because it uses a sodium iodide symporter also the Wolff-Chaikoff effectt - increases in serum iodide levels also inhibit the iodine organification

How does the treatment for acute intermittent porphyria work?

glucose or hemin inhibits ALA synthase so that there is not an accumulation of ALA or PBG usually caused by medications, alcohol use, smoking, progesterone or low-calorie diet

Enterococcus

gram positive cocci in chains and no hemolysis on blood cultures cause UTI, biliary infection and endocarditis

How should you recognize schistomsomiasis?

granulomatous inflammatory response --> manifestations in GI, Bladder and periportal system will see eosinophilia early in the disease process. tx with praziquantel

Patient with phospholipase A2 receptor antibodies and nephrotic syndrome. What is the dx?

has membranous nephropathy this is because antibodies against PLA2R - primarily IgG4 - lead to immune deposition in the glomerulus titers will correlate with disease activity

Type 1 diabetes and the risk of hypoglycemia?

have increased risk because exogeneous insulin is not subject to the same regulation as endogeneous insulin. therefore they will still absorb from the injection site even if glucose is falling. long term diabetics also have alpha cell failure that leads to decreased glucagon secretion so they have a greater risk of hypoglycemia

Heme Synthesis pathway importnace

heme is synthesized in erythrocytes, but only in immature erythrocytes that have their mitochondria when they mature and loose their mitochondria, then they will no longer make heme

Child with Reyes syndrome, what is the pathology?

hepatic failure and acute encephalopathy due to use of aspirin hepatic dysfunction - microvesicular steatosis - presentce of small fat vacuoles in the cytoplasm of hepatocytes (no necrosis or inflammation) EM - swelling, decreased number of mitochondria and glycogen depletion encephalopathy of Reye syndrome - toxic effect of hyperammonemia on the CNS leading to cerebral edema

What is the inactive form of malaria in the liver?

hepatic schizonts is the form of plasmodium falciparum mefloquine ppx must be given for 4 weeks to ensure those released are destroyed - typically over 8 to 30 days need ppx with atovaquone-proguanil, doxycycline, and mefloquine

Patient with dypsnea, hypoxemia and patchy alveolar infiltrates have what?

high altitude pulmonary edema reduced partial pressure of oxygen (PiO2) at high altitude __> hypoxic pulmonary vasoconstriction and increased pulmonary arterial pressure causes alveolar capillary membrane disruption and leads to patchy, bilateral pulmonary edema

COPD respiratory curves

higher FRC - breath at a higher lung volume TLC will increase the absolutel volume of air in the lungs that is not respired the RV will increase

What is propofols mechanism of action?

highly lipid soluble so it has a very short duration of action -- there is rapid redistribution from the brain to other tissues (like fat) due to this

Propofol onsent of action physiology

highly lipohpilic anesthetic drug used for inducation and maintaince of general anesthesia preferentially is distributed to organs recieving high blood flow which leads to the initial distribution and rapid onset of sedation then it is redistributed to ogans receiving less blood flow

Patient with a pruritis, papulopustular rash after a recent vacation. Others also infected. What is the cause?

hot tub folliculitis seen in hotel swimming pools or hot tubs that allows for pseufomonas aeruginosa proliferation motile, gram negative rod that is oxidase positive and produces and pigment

How have tumor cells developed resistance to chemotherapy?

human multidrug resistance gene P-glycoprotein that is a transmembrane protein that functions as an ATP-dependent efflux pump.

What do direct arteriolar vasodilators do?

hydralazine and minoxidil lower BP but then this results in sympathetic activation and increases in HR, contractility, and CO works on RAAS to result in sodium and fluid retention with peripheral edema

Patient with cholesterol gallstones who does not want treatment with surgery. What is a suitable treatment option?

hydrophilic bile acids (ursodeocycholic acid) which reduces cholesterol secretion and increasease biliary bile acid concentration improves cholesterol solubility and promotes gallstone dissolution.

Physiology of hyperparathyroidism

hypercalcemia d.t 1. increased renal tubular Ca absorption (although may have net hypercalciuria due to increased filtered calcium load) 2. increased renal production of Vitamin D3 --> increases Ca2+ absorption 3. increased bone resorption hypophosphotemia due to decreased phosphate reabsorption in the proximal renal tubule

What would cause VEGF -induced tissue proliferation?

hypergranulation tissue that will prevent would epithelization and remodeling these lesions occur at the site of nasogastric tubes or wounds that are left to heal by secondary intention

What are the side effects of ARBS?

hyperkalemia, gynecomastia, impotence and decreased libido

Patient with BPH that responds well to 5-alpha reductase inhibitor. What was his BPH most likely caused by?

hyperplasia of the epithelial components of the prostate gland. if stromal hyperplasia (with smooth muscle predominance) then they will respond best of alpha-1-blockers collagen predominance respond to neither

Patient with CF, bronchiectaisis and massive hemoptosis? What is the cause

hypertrophic bronchial arteries in response to chronic and recurrent airway inflammation. This leads to neovascularization - and with hemoptosis - mosr elikely from the bronchial arteries in the systemic circulation

Patient with increased LV volume with prominent intraventricular septal hypertrophy has what? how to treat?

hypertrophic cardiomyopathy use beta blockers -- improve sxs through increased LV volume that reduces LV outflow and improves cardiac output 1) reduce HR -- increasing EDV 2) reduce LV contractility - reduces the amount of blood ejected during systole

Patient with a hemoglobin level of 42. She is awake and alert and says she feels hungry but has not other symptoms. Why?

hypoglycemia --> activation of the sympathetic NS (NE or Epi) to increase the secretion of glucagon, cortisol and growth hormone neuro sxs: due to NE/epi and acetylcholine release -- tremulousness, tachycardia, and anxiety/arousal. acetylcholine causes sweating, hunger and parathesias neuroglycopenic sxs -- inadequate availability of glucose in the CNS -- behavioral changes, confusion, visual disturbances, stupor and seizures reduced awareness of symptoms usually nonselective beta blocker -- will still have the acetylcholine symptoms beta blockers make it worse because usually epi would stimulate hepatic gluconeogenesis and peripheral glycogenolysis as a result

Patient with episodes of hypoglycemia in the setting of T1DM. Given emergency glucagon. How does it work?

hypoglycemia will manifest with: 1. neurogenic - anxiety, tremor and sweating 2. neuroglycopenic symptoms - confusion, loss of consciousness and seizures emergency glucagon -- increases hepatic glycogenolysis and return to consciousness in 10-15 minutes

What are the side effects of HCTZ?

hypokalemia hyponatremia hypomagnesemia hypercalcemia

Patient with incomplete fusion of the urethral folds. What is the dx? what about labioscrotol folds? What about genital tubercle?

hypospadius p abnormal opening on the ventral surface bifid scrotum epispadius - abnromal opening on the dorsal surface of the penile shaft

Cardiac Tamponade Findings

hypotension, elevated JVP and muffled heart sounds echo will show pericardial fluid accumulation with late diastolic collapse of the right atrium (due to the displacement of pericardial fluid with ventricular expansion. pulsus paradozus - exaggerated drop in systolic BP during inspiration

Imaging of honeycomb pattern in the periphery?

idiopathic pulmonary fibrosis

Patient with diabetes insipidus. How do you know if it is posterior pituitary or hypothalmus?

if below the infundibulum, then will be tranisent because the cell bodies of the nuerons remain intact and neruons can undergo regeneration. if hypothalmic injury results in the death of magnocellular neurons --> permanent centra DI

How to tell if the nondisjunction occured in Meiosis 1 of 2?

if the child recieved 2 different bands from the mother, this means that he inherited both of her homologous chromosomes. This means the problem occured in meiosis I. Down syndrome usually arises from Meiosis I

Lobar consolidation will show what on x-ray

if the consolidation abuts a fissure (oblique, horizontal), there can be a sharper delineation due to consolidation that cannot directly spread across the fissue to another lobe

What does a median nerve injury present with?

impairment of forearm pronation (pronator teres) impairment of proximal interphalangeal joint flexion -- digitorum superficialis sensory nerve in a median distribution

What is the difference between transference and displacement?

in displacement, a person expresses unacceptable feelings for one person to a neutral person or object.

Pralidoxime is given when?

in organosphospate poisioning only when there is muscle weakness and only after atropine is given.

Red Man Syndrome

in response to vancomycin note this is not a true allergic reaction (does not activate IgE) therefore it can be resummed. the reaction just occurs from quick infusion into the blood stream activating histamine directly

When should you not give acetazolamide?

in salicylate toxitiy, because it alkanizes the urine at the expense of acidifying the blood BAD for salicylates because need to remove H in the blood or it will deposit into the tissues

Where is the majority of water reabsorbed in the nephron?

in the proximal tubules (reabsorpbs >60% of water) in the distal nephron - water is only absorbed based on the hydration state -- therefore the proximal tubule is really the main regulator

What effect does estrogen have on thyroid hormone?

increase in estrogen activity --> raises circulating TBG levels -- reduction in free T4 and T3 levels will lead to an increase in TSH and increased thyroid hormone production until additional TBG is saturated. Therefore this is a euthyroid state and leads to an increase in the total T4 and T3

Mutation in the phosphoribosyl pyrophoaspate synthetase gene causes what?

increase synthesis of urines which will cause gout this enzyme is involved in purine synthesis

What do competitive inhibitors do to the Vmax and TKm

increase the Km but do not change the Vmax - this is because it can be overcome by supersaturating the receptor

What are the diagnostic findings if the neuropore does not fuse?

increased AFP and AchE because these are allowed to leak into the amniotic fluid

Patient with right sided heart failure but no edema. What is the mechanism?

increased capillary fluid transudation --> raises intersitial hydrostatic pressure which results in increased lymphatic drainage this allows for a compensatory response that can delay the development of edema

Patient with athletes heart. What happens to LVEF, LV cavity size, maximum cardiac output?

increased maximum cardiac output is due to increased stroke volume to meet demands of endurance training - gradually increase red blood cell mass and plasma volume to increase oxygen carrying-capacity. skeletal muscles develop increased arteriolar and capillary density -- improves oxygen uptake and causes overall reduced systemic vascular resistance increased blood volume and reduced SVR --> increased venous return. places increased volume load on the left ventricle. left ventricle undergoes phsyiologic eccentric hypertrophy to increase left ventricular cavity size and improve diastolic because the end diastolic volume and stroke volume are proportionately increased, left ventricular ejection fraction is mostly unchanged.

What differences in infants makes their response to drugs different.

increased proportion of total body water with lower content of body fat -- this makes water soluble drugs have a larger than expected volume of distribution relative to body mass --> lower plasma concentrations when at the same weight neonates have decreased plasma protein concentrations compared to adults -- can increased free levels of highly protein bound drugs elevated bilirubin levels in neonates can further increase the concentration of unbound drug by displacing them from albumin binding sites

What is the bodys response to decompensated heart failure?

increased sympathetic output d/t decreased perfusion of the baroreceptors --> increasing arteriolar resistance decreased renal perfusion --> activation of RAAS

What happens to urea in a hypovolemic patient?

increased urea reabsorption because of antidiuretic hormone (d/t increased permeability in the inner medullary collecting ducts) this functions to increase the gradient in the tubules

Patient with insulin resistance. What else will be seen that is correlated with this?

increased waist circumference due to increased visceral fat is associated strongly with insulin resistance insulin also causes an increase in triglycerides and low HDL levels due to resistance

What are risk factors for cataracts? why?

increases with age, in smokers, excessive sunlight exposure, diabetes mellitus and glucocorticoid use in hyperglycemia there is oversaturation of the polyol pathway

Changes in prevalance with positive and negative predictive value

increasing prevalance -- NPV decreases and PPV increases decreasing prevalance - NPV increases and PPV decreases

How to decrease the number of wrong operation sites?

independent verification of the patient, procedure and site by 2 health care workers

Primary syphillis presents with what?

indurated and painless ulcer near the glans penis

When does autosomal recessive PKD present and with what other symptoms?

infancy with bilateral flank masses will have cysts and fibrosis in the liver -- presents with protal HTN

Patient with constant back pain that fails to improve with positional changes, rest or analgesics. What is the dx?

infection or malignancy *older pt without hx of IV drug use think neoplastic, especially if the pain is worse at night

Patient with painful external rotation against resistance and preserved abduction of the shoulder has what injury?

infraspinatus injury teres minor help with adduction and external rotation

Patient with lethargy, ataxia, disorientation, slurred speech that was followed by rapid improvement and a perioral and perinasal rash. what is the dx?

inhalant use disorder glue sniffers rash dermatitis around the mouth or nostrils of chronic users immediate effects because they are lipid soluble and act as CNS depressants -- brief transient euphoria, lethargy, disorientation, loss of consciousness, poor coordination and slurred speach

What do trimethoprim, methotrexate, and pyrimethamine all have in common?

inhibit dihydrogolate recutase

What role do bisphosphanates play in osteoporosis?

inhibit osteoclast-mediated bone resorption so they have no estrogen agonist or antagonist activity and do not lower the risk of breast cancer

What does it mean to have clasp-knife spasticitpy

initial resistance to passive flexion followed by sudden resistance seen in UMN lesions d.t lack of UMN inhibition of spinal stretch reflex arch (because in passive arm felxion, the extensor muscles are activated by the disinhibited stretch reflex and then they are overcome)

Patient with total abdominal hysterectomy for symptomatic uterine fibroids. Surgery was performed at the lower aspect of the uterus at the cardinal ligament - compressing bladder. now with fever and right sided back pain and normal urination

injury to the right ureter this is a retroperitoneal structure -- travels along the lateral pelvic sidewall posterior to the ovarian vessels to dive under the uterine vessels (water under the bridge) flank pain due to distension of the proximal ureter with urine. can void normally because the second ureter is uninjured

What happens with damage to the radial nerve?

innervates the extensor pollicis longus and brevis and this controls tumb extension

What is the pathogenesis of coal workers pneumoconciosis?

inorganic dust is inhaled and the finest particles are phagocytized by alveolar macrophages note: larger particles can be trapped by mucus and swept upward, but this is not the pathogenesis of pneumonconeosis.

What is lipofusion?

insoluble pigment composed of lipid polymers and protein complexed phospholipids sign of wear and tear or aging this is the product of free radical injury and lipid peroxidating

What does high levels of fructose 2,6, bisphosphate mean?

insulin causes the activation of PFK-2 which increases F26BP and augments glycolysis at the same time, F26BP leads to decreased conversion of alanine and other glucogenic substrates to glucose

PKU

intellectual disability, gait or posture abnormality, eczema, and a musty body odor are signs of PKU AR

Neonate with bilious emesis and signs of intestinal atresia. What is the pathophysiology?

intestinal atresia is due to vascular occlusion in utero. leads to ischemia of a segment of the bowel with subsequent narrowing or obliteration of the lumen. proximal segment that ends in a blind pouch. distal segment of ileum that assumes a spital configuration around an ileocoloic vessel. apple peal or christmas tree deformity

What is most effective in downregulating gastrin secretion?

intestinal influences ileum and colon release peptide YY which binds to receptors on the ECL cells. counteracts the cephalic and gastric phases of acid secretion by inhibiting gastrin stimulated histamine release from ECLs. Somatostatin and prostaglandins also inhibit release.

Patient with leukemia who recently underwent chemotherapy and now has febrile neutropenia. Found to have fungus. What is most likely cause?

invasive pulmonary aspergillosis CXR with consolidation, nodules or cavitary lesion. candida is common but would not result in a lung infection - more likely to have a bloodstream infection.

How do pencillins and cephalosporins function?

irreversible bind to PBP -- transpeptidases are one form of PCB that function to cross link peptidoglycan in the bacterial cell wall -- therefore inhibiting this will lead to cell wall instability and bacteriolysis

Patient with fever, cough and PNA. Likely in septic shock. What fluids should be given?

isotonic crystalloid - can given 0.9% saling or LR through large-bore peripheral IV catheters

In panic disorder, why would buspirone be used?

it has no risk of dependence in contrast to BZOs

Patient with damage to the 12th rib posteriorly. What was likely injured?

kidney sits by the 12th rib 12th rib also associated with the parietal pleura laterally. spleen is located at the 9th, 10th and 11th ribs fractures 1-6 have the greatest risk of damaging the parietal pleura

How does the kidney regulate acid balance?

kidney utilizes acid buffers to trap H+ to not totally low urinary pH HPO4 2- NH3 therefore in acidosis will see a decrease in HPO4 as it buffers

Patient presents with reddish skin discoloration, tachypnea, headache, and tachycardia. What will you see on labs? What does he have? Treatment?

lactic acidosis and narrowing of the venous-arterial PO2 gradient inhalation of amyl nitrate because it will oxydize ferrous iron present in hemoglobin to ferric iron --> generates methemoglobin. This is incapable of carrying oxygen but has a high affinity for cyanide. will bind and sequester cyanide in the blood to limit its effects also could use hydrocobalamine and sodium thiosulfate as antidotes

Patient with flatulence, crampy abdominal pain, and watery diarrhea after consuming milk products. What is on their labs?

lactose intolerance secondary lactase deficiency due to inflammation or infection since not made into a monosaccharide -- the undigested lactose is fermented by gut bacteria -- decreased stool pH and increased breath hydrogen content. will also see an elevated stool osmolaltiy.

What artery is blocked with ST elevations in leads I and aVL?

lateral MI - occlusion of the left circumflex artery leads V5 and V6 are also elevated with a lateral MI

What does detrussor muscle overactivity cause?

leads to urge incontinence -- more common in women controlled by parasympathetic fibers from the pevlic splanchnic nerves and inferior hypogastric plexus

What does a TEE look at?

left atrium is the most posterior surface of the heart and can see the mitral valve to be well visualized. behind can see the descending thoracic aorta

Intraventricular septum perforation presents with what?

left to right shunt and symptoms of acute heart failure -- chest pain, dyspnea, symptoms of cardiogenic shock and a harsh holosystolic murmur on the left sternal border

What causes the corneal reflex?

lesion from CN V1 (afferent limb) or CN VII (efferent limb)

Granulation Tissue

lesion with abundant capillaries and fibroblasts

Patient with pleuritic chest pain 2 days after an MI

likely a postinfarction fibrinous pericarditis.

Patient with a psudomonas infection that has an enzyme located on the cytoplasmic surface of the cell membrane and this catalyzes the transfer of acetyl groups to exogeneous substances?

likely aminoglycosides -- gentamicin

If there is spread to the skeletal system, how did it occur?

likely happened due to hematogeneous spread in the case of the prostate, this would occur via the vertebral venous plexus which communicated with the prostatic venous plexus. this explains mets to the spine.

Patient with rapidly progressive (cresecentic) glomerulonephritis. no immune complexes or complement on LM. with nasal symptoms.

likely has Pauci-immune RPGN. will have a positive ANCA

Patient with hx of drug use now with fever and new onset aortic regurigation. Also with hypotension and pulmonary edema. autopsy shows symmetric bilateral wedge shaped strips of necrosis over the cerebral convexity, parallel and a few centimeters lateral to the interhemispheric cerebral fissue. What is the cause of these findings?

likely has cardiogenic shock -- these bilateral wedge shaped strips of necrosis are due to global cerebral ischemia profound systemic hypotension -- causes neuron cells death. this will occur in brain regions with high metabolic demand (hippocampus, cerebellar purkinje cells) and areas supplied by the distal most branches of cerebral arteries. this results in bilateral wedge shaped strips that can extend from the frontal to occipital lobe

Kidney reabsorption principles include Tmax which means

limit to the rate of reabsorption which is called the transport maximum. this is determined by the capacity of transporters to be available for active reabsorption glucose will demonstrate this principle

Pregnant Patient with febrile gastroenteritis (fever, vomiting diarrhea) and gram positive rods in blood stream. What is dx? What factors does it have to evade the host immune response?

listeria monocytogenes faculatively intracellular organism listeriolysin O - generates pores in phagosome membranes, which allows phagocytosed L monocytogenes to escape into the cytoplasm of monocytes and avoid lysosomal destruction Actin-based transceullar spread - hijacks the actin-based cellular motility mechanism of host cells -- allows it to spread to adjacent cells without reentering the extracellular space. infections primarily controlled using a cytotoxic T cell response

Patient presents with weight gain, hair loss and mild bradycardia in the setting of a recent manic episode. What is the medication she is taking?

lithium causes hypothyroidism other SE: nephrogenic diabetes insipidious, chronic tubulointersitial nephropathy, Ebstein anomaly

Patient with a lobar pneumonia? What is the most likely potential pathogens? and then patient is activating Th1 cells, what is the most likely?

lobar pneumonia - H flu, Staph aureus, strep pneumoniae cell-mediated immune response is involved in intracellular infections - legionella is intracellular and it has a resistance factor that inhibits phagolysosome fusion other intracellular bacteria (mycobacteria - inhibits phagolysosome acidification) and listeria (allows bacteria to escape from the phagolysosome)

How does angiotensin cause feedback to inhibit

long -lopp will decrease renin release via intrarenal baroreceptor and cula densa pathways inhibits angiotensin on the juxtaglmerular cells from releasing angiotensin II

Pathogenesis of diabetic autonomic neuropathy?

long standing hyperglycemia --> accumulation of cross-linked glycosylated serum proteins in the vasa nervorum --> inflammation and damage of the peripheral n. think of the feet, but also sympathetic and parasympathetic nervous system

When you are testing for strep, what are you testing?

looking for the antigen - use rapid antigen detection testing - looking for GAS antigens

How does loperamide decrease peristalisis?

loperamide is a mu opiod agaonist -- inhibits acetylcholine release from the myenteric plexus neurons to slow peristalsis transit time in the intestine is prolonged -- allowing for increased water absorption. unlike other opiates -- loperamide undergoes high first pass metabolism and does not cross the blood brain barrier

Pathogenesis of idopathic pulmonary fibrosis

loss of type 1 pnumocytes due to lung injury from smoking -- involved in gas exchange Type 2 pneumocytes will undergo hyperplasia (act as the stem cell) but do not end up differentiating

What precipitates cholesterol stones?

low bile salts and phosphatidylcholine cholesteol --> acids by cholesterol 7 alpha hydroxylase as the rate-limiting step in bild acid synthesis bile acids are then conjugated wot glycine or taurine to improve the solubility and emulsifying ability to create the bile salts that are actively secreted into bile canaliculi

Epinephrine

low doses - B2 vasodilation predominates high doses - a1 induced vasoconstriction will become more pronounced

When is an S4 heard and what does it mean?

low-frequency diastolic sound that occurs during the atrial kick of ventricular diastole - reflects blood colliding with a stiff ventricular wall. hypertrophic cardiomyopathy or concentric left ventricular hypertrophy

How do ACE inhibitors cause damage in patients with HTN?

lower angiotensin II levels -- systemic vasodilation and reduced BP cause efferent arteriolar dilation -- lower intraglomerular pressure, so it cannot maintain GFR in the setting of reduced renal perfusion leads to acute renal gailure

Hypersensitivity Pneumonitis looks like what on path?

lymphocytic infilatrate with poorly formed noncaseating granulomas -- progressive alveolar septal firbosis restrictive pattern

What will you see on CSF in HSV1?

lymphocytic pleocytosis, normal glucose and elevated protein. usually elevated erythrocytes in the CSF.

Elastin formation

lysyl oxidase (dependent on copper) - deaminate some of the lysine residents which allows for the formation of desmosine cross links between neighboring polypeptides -- CROSS links hold elastin together, not disulfide bridges

Why are patients with silicosis more at risk of mycobactrium tuberculosis?

macrophages respond to silica and release fibrogenic factors that lead to fibrosis. phagolysosomes may impair macrophages and lead to susceptibility

Patient with a lesion on the tounge 2 cm anterior to the foramen cecum. What is causing his pain?

mandibular branch of the trigeminal n. foramen cecum divides the anterior 2/3 of the tounge from the posterior 1/3 of the tongue

What does it mean to use suppression defense mechanism? intellectualization?

mature defense mechanism conscious choice not to dwell on a particular thought or feeling intellectualization - immature defense mechansim - forcus on the nonemotional components of a distressing event to make it more tolerable

What part of the processing contains complementary binding to a sequence of TTT's?

mature mRNA - 5' capping: 7-methy guanosine cap that is added to the 5' end - polyadenylation: poly-A tail that is added to most eukaryotic mRNA molecules (AAUAAA) consensus sequence that is located near the 3' end of the RNA molecules directs the addition of this tail (not on the DNA) - introns have a GU at the 5' splice site and AG at the 3' splice site

What does an abnormal ristocetin cofactor assay mean?

measure in virto vWF dependent platelet agglutination. activates GP 1b treceptors on the platelets and makes them available for vWF platelet binding. with vWF deficiency, there is poor platelet agglutination in the presence of ristocetin but will normalize with normal serum

Lower extremity lymphatic drainage

medial -- runs along the long saphenous vein to the superficial inguinal lymph nodes, bypassing the popliteal nodes (only inguinal lymphadenopathy) lateral lesions -- drain by the lateral track and communicate with the popliteal and inguinal nodes -- cause lymphadenopathy in the popliteal and inguinal areas

Pronator teres syndrome

median nerve in the forearm courses between the humeral and ulnar heads of the pronator teres muscle and between the flexor digitorum superficialis and flexor digitorum profundus muscles before entering the hand in the carpel tunnel

Patient with a raised pigmented skin lesion on the leg, with nests of uniform round cells at the basal portion of the epidermis. bx shows nests of uniform round cells at the basal portion of the epidermis that extend into the underlying dermsi, inconspicuous nucleoli and no mitotic activity.

melanocytic nevi benign neoplasmas with round uniform melanocytes that are mitotically quiescent. usually less than 6 cm in diameter 1. junctional nevi - limited to the dermoepidermal junction. flat, black-to-brown pigmented macules with darker coloration in the center than the periphery and preserved skin markings 2. compound nevi - form as the aggregates of nevus cells extend into the dermis - raised papules with uniform brown to tan pigmentation. both dermal and epidermal involvement. 3. intradermal nevi - older lesions in which the epidermal nests of the nevus cells have been lost. remaining dermal nevus cells loose tyrosinase activity and produce little to no pigment. sometimes pedunculated

Patient with pelvic fracture and unable to pass foley cathetetor to relieve bladder obstruction. Which part of the urethra is injured?

membranous urethra because it is unsupported by the adjacent tissues and is the weakest point of the posterior urethra

How is isoniazid metabolized?

metabolized by acetylation to N-acetyl-isoniazin in the hepatic microsomal system by the enxyme N-Acteyl transferase the acetylization rate will vary the length of activity of the drug and therefore the therapeutic dose of the drug

How is morphine metabolized and removed from the body?

metabolized by the liver via glucronidation -- forms 2 major metabolites morphine -3 glucoronid and morphine -6-glucoronide then are renal eliminated if renal dysfunction, there will be metabolite accumulation and opiod toxicity

Metronidazole drug interactions

metronidazole should not be used with alcohol due to disulfuram like reaction -- happens shortly after consumption

Patient who immigrated and has a murmur with a loud S1 and a diastolic murmur heard at the end of diastole.

mid to late diastolic murmur - mitral stenosis. due to underlying rheumatic heart disease pt will usually experience exertional dyspnea as the first symptoms -- inability to increase cardiac output to meet exertion demands. as MS worsens - elevated left atrial pressure can lead to orthopenea, paroxysmal nocturnal dyspnea and cough with right heart failure mod diase - absense of volume overload and loud S! (stiff leaflets snapping shut)

Patients with DM are most likely to show what on their urine?

moderately increased albinuria

Hashimoto Thyroditis path

mononuclear infiltrate consisting of lymphocytes and plasma cells with germinal centers

Hepatitis C

more commonly from IV drug use (not sexual infection) acute infxn is usually asymptomatic chronic infxn -- dermatologic manifestations (cryoglobulinemia)

Patient with a cavernous hemagioma of the liver. What is most likely?

most common benign liver tumor

Autoimmune Adrenalitis

most common cause of PAI and occurs due to autoantibody formation --> atrophy of the bilateral adrenal glands

Patient with an elevated AFP for dates. What is the most likely dx?

most common cause of abnormal AFP is a dating error other causes are open neural tube defects, multiple gestation and abdominal wall defects causes of decreased AFP are trisomys

Niacin (Vitamin B3)

most effective agent for raising HDL levels, does not reduce the risk of cardiovascular events

Patient with a left sided mass that presents with lower extremity edema.

most likely a RCC these like to invade the renal vein and will invade the IVC to cause abdominal collateral vein swelling

Patient with metastatic disease to the liver. How did it spread there?

most likely came from the colon -- whcich spreads through the portal venous system to the liver liver is vulnerable to metastatic disease due to 1. fenestrated hepatic sinusoidal epithelium 2. dual blood supply

Patient who presents with cushing syndrome and SLE?

most likely iatrogenic cushing syndrome due to prolonged administration of glucocorticoids for management of symptoms.

What complexes are most likely to contain both protein and RNA in the cell that are floating in the cytoplasm and bound to the ER? Where is this synthesized?

most likely to be ribosome these are synthesized by the nucleolus, this is where rRNA is transcribed

What of the flouroquinoles will not cover psudeomonas?

moxifloxacin will not cover psuedomonas - must use cipro of levo.

Patient with systemic neutropenia is most at risk for what type of infections?

mucositis - damage to rapidly dividing epithelial cells of the digestive tract creasts breaches in the mucosal barrier and allows endogenous bacterial flora to penetrate and enter the bloodstream. neutropenia - because neutrophils are the first line of defense, those that penetrate the mucosa or cutaneous barrier rapidly spread. thus, fever is the only sign of infection.

What are the effects of hypokalemia?

muscle weakness, cramps, possible rhabdomyolysis

Patient with Gaucher disease and being given recombinant beta-glucocerebosidase. How is this administered?

must be given IV because large polypeptides are not well absorbed in the GI tract glucocerebrosidase can enter cells by binding to mannose-6-phosphate receptors --- found in the Golgi netowrk where they help synthesize lysosomal proteins *also are expressed on the cell surface where they bind lysosomal enzymes that are accidently decreted - these can bind and cause endocytosis

The blood content of the aorta and other organs are measured at rest in an experiment. Which will have the greatest differences?

myocardial oxygen extraction is really high -- so the coronary sinus will be the lowest (cardiac venous blood)

Patient who wants to stop drinking alcohol. What pharmocotherpy exists?

naltrexone - blocks the mu-opiod receptor and inhibits the reward and reinforcing effects of alcohol, reduces cravings and improves motivation to quit. can be given as monthly injections Acomprosate - modulates glutamate neurotransmission at the NMDA receptor Disulfram - aldehyde dehydrogenase inhibitor that is considered second line

What does vitamin B6 do?

neccessary for transamination and decarboxylation of amino acids. This is used in gluconeogenesis and other essential biochemical processes active form in pyridoxal phosphatase

Genetic mutations that drive oncogenesis and create unique proteins not found on healthy cells are called what?

neiantigens -- these will be displayed on surface tumor cells and subsequently recognized by patrolling cytotoxic T cells as not self and therefore destroyed. these are particularly common in cancer that have defects in mismatch repair proteins and high micro satellite instability.

Pathology of a lung abscess

neutrophils are the major regulators activated and release cytotoxic granules containing MP and other digestive enzymes that destroy extracellular bacteria. cause damage to the pulmonary parenchyma and result in liqufactive necrosis

Patient with venous blanching and induration and pallor of the tissues surrounding the norepinephrine infusion site. What is the dx and how to you treat?

norepinephrine extrvasation -- norepinephrine leak causes intense alpha 1 receptor mediated vasoconstrction --> local tissue necrosis give patient pentolamine - alpha receptor blocker that leads to vasodilation

What ion movements occur at stable electrical potential?

normal - low concentration of Na and CL in the cell, and high concentration of K+ in the cell. equilibrium potential - electrical potential difference that moves K+ ions into the cell at the same rate as they leave the cell along the gradient. chloride is an ion that is largely located outside of the cell, therefore the gradient will push Cl into the cell

Molar Pregnancy - Complete

normal 46 XX due to only paternal DNA being present from gestational trophoblast disease (trophoblastic hyperplasia leads to elevataed BHcG has no fetal structures - large edematous and disordered (bunch of grapes) pt with pelvic pain and vaginal bleeding

Patient is pregnant. What would you see on her ABG?

normal physiology of pregnancy is chronic hyperventilation elevated progesterone levels --> sensation of SOB and stimulate the hypothalmus to increase the respiratory drive increased by increasing the tidal volume respiratory alkalosis with metabolic compensation (increased renal bicarbonate excretion) arterial oxygenation is slightly above normal which helps facilitate the transport of acidic waste from that oxygen to the developing fetus.

Children at a daycare all get watery diarrhea. What is the most likely cause?

norovirus most common cause of viral gastroenteroisis most commonly fecal oral spread note rotavirus also presents similarly, but the childhood vaccine has greatly reduced this

Lesch-Nyhan Syndrome effects

not able to complete the purine salvage pathway (cannot convert guanosine --GMP and hypoxanthine -->IMP) increased use of the purine synthesis pathway - which starts with PRPP

A patient with xeroderma pigmentosum is prone to developing multiple skin cancers starting in childhood.

nucleotide excision repair defect UV specific endonucleases

What are the four adhesion molecules for neuroendocrine tumors?

nueral cell adhesion molecule (CD56), neuron-specific enolase, chromogranin, synaptophysin

Medullary Thyrodi Cancer

nueroendocring tumor calcitonin - secreting parafollicular C cells shows nests or sheets of polygonal or spindle shaped cells with extracellular amyloid depositis

Patient with right-sided face and arm swelling and engorgement of subcutaneous vein on the same side of the neck. Where is the vein obstructed?

obstructed right brachiocephalic vein. because the right external jugular vein drains into the right subcalvian vein also the right brachiocephalic vein also drains the right lymphatic duct which drains lymph from the right upper extremity, the right face and neck, the right hemithorax and the right upper quadrant abdomen

Alpha-1 Antitrypsin (AAT) Deficiency

obstructive pattern -- emphysema panacinar pattern of emphasema increased TLC, decreased FEV1 to FVC ratio and decreased DLCO (d/t destruction of alveoli and ajoining capillary beds)

What is the pathogenesis of CO poisoning?

occurs because of COs ability to competitively bind iron present in heme proteins. binds heme iron with a much higher affinity than oxygen forming carboxyhemoglobin. the remaining heme groups have increased oxygen affinity, with a left shift of the oxygen dissociated curve and impedes oxygen delievery to tissues. CO can also bind to cardiac myoglobin with high affinity and disrupt the hearts ability to use oxygen and therby decrease CO cells Co binds to cytochrome oxidase which inhibits aerobic metabolism and exacerbates tissue hypoxia

Supine Hypotension syndrome pathology

occurs only in pregnant women hypotension, pallow, sweating, nausea and dizziness due to the gravid uterus compressing and obstructing the inferior vena cava --> reduced venous return

When would you have decreased first pass metabolism occur?

occurs with drugs that are given in a route other than orally -- this allows it to be in the systemic circulation without passing through the portal circulation first

What does Vitamine E deficiency present with?

occurs with fat malabsorption and abetalipoproteinemia. hemolysis and nuerologic dysfunction due to free radical damage of cell membranes looks like friedrich ataxia and vitamin B12 deficiency

Wernike Encephalopathy presentation

oculomotor dysfunction, ataxia, encephalopathy d/t thiamine deficiency - Vitamin B1 mamillary bodies are affected

Arsenic poisioning path

odorless, tasteless and easily absorbed after injestion or inhalation -- get toxicity from pesticides/insecticides, contaiminated water, pressure treated wood binds to sulfhydral groups --> impairs cellular respirtaion and inhibits pyruvate dehydrogenase

Lac operone

one mRNA transcript codes the sequences for many proteins -- one mRNA molecule can be translated into multiple proteins of polypeptides this is all regulated by one operator, a promoter and a dingle group of regulatory elements

DNA polymerase I

only in prokaryotes it has 5' to 3' exonuclease activity that allows it to degrade RNA primers

What is dynorphin?

opioid peptide that modulates the pain response - produced mainly in the periaqueductal gray, rostral and ventral medulla and the dorsal horn of the spinal cord

HIV patient will typically present with...

oral thrush

Patient receives the live attenuate oral (sabin) poliovirus vaccine. How does this compare to the inactivated virus?

oral will produce a much stronger mucosal secretory IgA immune response than the inactived poliovirus (SALK). increased IgA offers immune protection at the site of viral entry by inhibiting attachment to intestinal epithelial cells.

Patient with personality change, disinhibition and irritability. Where is the lesion?

orbitofrontal cortex frontal lobe with strong connections to the limbic system -- involved in behavioral and emotional regulation

osteoblasts vs osteoclasts

osteoblasts - single nucleus that arise from mesenchymal stem cells dound in the periosteam and bone marror osteoclasts - mononuclear phagocytic cell lineage and form when sever precursor cells fuse to create a multinucleated cell * form in response to macrophage colony stimulating factor (M-CSF) *activated nuclear factor kappa -B ligant

Patient with osteogenesis imperfecta. What process is impaired?

osteoid production by osteoblasts type 1 collagen is the predominant collagen in osteoid and allows the bone to be flexible but maintain strength. Type 1 is in teeth, ligaments, skin and sclera

Patient with MS who has urinary frequency and urge incontinence. What is the dx?

overactive or spastic bladder due to the presense of an upper motor neuron lesion urodynamic studies show little or no residual urine after emptying as bladder contractility is normal but distensibility is poor. bladder does not distend or relax due to loss of inhibitory control

How does the PAS stain work

oxidizes carbon-carbon bonds --forms alehydes that produce magenta color really good at highlighting polysaccharides of the fungal wall, mucosubstances secreted by epithelia, and basement membranes

How does primary syphilis present?

paincless single genital ulcer - chancre

What function do eosinophils perform in parasite defense? Hypersensitivity reactions?

parasites: - stimulated by !L-5 produced by Th2 cell -parasite will be coated by IgG and IgA that bind to Fc on eosinophil surface --> eosinophil degranulation and release major basic protein and ROS --> antibody dependent cell-mediated cytotoxicity - used by macrophages, neutrophils and natural killer cells T1HS - synthesize prostaglandins, leukotrienes and cytokines that contribute to the inflammation seen in late-phase type 1 hypersensitivity and chronic allergic reactions

Injury to the vagus nerve in the abdomen during surgery. What is the result?

parasympathetic inervation to the GI tract and stimulates gastric muscle contraction and motility. injury to the vagal trunk leads to delayed gastric emptying -- abdominal pain, early satiety and postprandial emesis note: intestinal peristalsis is mediated largely by the enteric nervous system. vagus nerve injury may cause transient intestinal dysmotility due to sudden loss, it would not cause long term dysfunction

Patient with diplopia and dysphagia and dry mouth. Also neuromuscular symptoms. What is the dx?

patient has nicrotinic and muscarinic symptoms which suggest c. botulinum. inhibits acetylcholine from presynaptic terminal -- so repeated stimulation will help increase the response.

Patient with duodenal ulcers. Where is the cause most likely?

peptic ulcers are most commonly due to helicobacter pylori infection or NSAIDS. H pylori preferentially colonizes the gastric antrum and is associated with decreased somatostatin formation and increased gastrin secretion --> stimulates the parietal cells to produce excess acid. this leads to increased acid load emptying into the proximal duodenum and leads to duodenal ulcers. gastric ulcers are associated with colonization in the gastric body. thought to be due to direct mucosal damage and chronic inflammation.

When doing an episiotomies, what are you likely to cut?

perineal body tendinous center point of the perineum -- separates the urogenital and anal triangles anchors: * bulbospongiosus muscle * external anal sphincter *superficial and deep transverse perineal muscles * fibers from the external urethral sphincter, levator ani and muscular coat of the rectum

Patient with muscarinic agonist. What is likely happening?

peripheral blood vessel walls lack cholinergic innervation, but M3 receptors are present on the endothelial cell surface. activation of M3 receptors promotes synthesis of NO --> diffuses into vascular smooth muscle cells and activates guanylate cyclase and increases intracellular cGMP. increasing levels of cGMP activate myosin light chain phosphatase -- dephosphorylates myosin and prevents interaction of the myosin head with actin --> smooth muscle relaxation and vasodilation vasodilation results in hypotension with persistently low blood pressure leading to somnolece due to inadequate cerebral perfusion

What does a person with schiozoid personality disorder do?

persistent pattern of social detachment, preference for solitary activities and limited emotion expressivity

What is involved in the first and second phase of a T1HS reaction?

phase 1 - IgE cross links and stimulates the release of preformed histamine and leukotrienes that cuase vasodilation and increased capillary permeability. phase 2 - Th2 release cytokines (in response to IgE) that releases cytokines and activates eosinophils -- major basical protein and eosinophil peroxidase causes tissue damage. This is a plpable indurated lesion

What are the phase 1, 2 and 3 trials?

phase 1 - test in humans, data on pharmacokinetic profile, metabolism, and properties. adverse effects monitored with increasing doses evaluated. includes only healthy subjects. phase 2 - efficacy in a small number of affected subjects. phase 3 - safety and effectiveness of a new treatment compared to a standard treatment. involves >/=2 groups of affected subjects phase 4 - adverse effects caused over time

3yo patient immigrated to US and has severe intellectual disability. Autosopy shoes pallor of the substantia nigra, locus ceruleus and vagal nucleus dorsalis

phenylalanine hydroxylase cannot convert phenylalanine into tyrosine hypoprimgentation involving the skin, hair, eyes and catecholaminergic brain nuclei

Experiment with decreased production of epinephrine by the adrenal medulla and cortisol from the adrenal cortex compared with control animals. What enzymes leads to lower epinephrine in experimental animals?

phenylethanolamine - N- methyltransferase expression of this enzyme is regulate by cortisol. after pitutiary resection -- loss of ACTH leads to decreased cortisol and decreased PNMT acitivity

Patient with 3 mo hx of headache and decrease libido now presenting with severe HA, cardiovascular collapse and visual deficits.

pituitary apoplexy

Pleural effusion vs. Consolidation physical exam?

pleural effusion - decreased or absent BS, decreased tactile fremitis, dullness to percussion consolidation - increased breath sounds, increased tactile fremitis, and dullness to percussion

Patient with transmural inflammation of medium sized arteries with areas of amorphous, eosin-staining arterial wall necrosis and areas of disruption of the internal elastic lamina are also present. What is the dx and risk factor?

polyarteritis nodosa correlation with hepatitis B and C

Patient with proximal muscle weakness in the upper and lower extremities without significant pain. What is Dx?

polymyositis can be associated with adenocarcinomas muscle enzymes are elevated (CK and aldose). anti-histidy-tRNA synthetase (anti-Jo-1) antibody bx shows endomysial inflammation without vascular involvement in a scattered or patchy distribution (dematomyositis causes perifasicular inflammation in a segmental pattern without vasculopathy

What is the antigen found in the capsule of H. Flu?

polysaccharide capsule - polyribosylribotal phosphage capsule protects the bacterium against phagocytosis and complement mediated lysis by binding factor H - a cirulating regulator protein that normally prevents C3b on host cells

Hypovolemic shock changes expected in this state?

poor organ perfusion and tissue perfusion --> tissue hypoxia with increased anaerobic metabolism and lactic acidosis leads to increased ventilation to increase CO2 exhalation

Pathogenesis of cirrhosis fluid overload and medications of choice

portal HTN --> splanchnic vasodilation and this decreases the affective arterial volume and lowers systemic blood pressure renal perfusion is reduced --> RAAH --> vasoconstriction and fluid retention block this using spironolacetone -- induces natriuresis without blocking the critical vasoconstrictive effects of angiotensin

What are acute phase reactants?

positive -fibrinogen, CRP, ferritin, hepcidin, ceruloplasmin, haptoglobin, vWF, and complement negative - albumin, transferrin and transthyretin procalcitonin - positive and negative properties - rise in response to bacterial toxins and fall in response to viral infection

Patient with a positive lepromain skin test (development of an indurated nodule at the site of injection). What is the mechanism of protection?

positive test means that there is tuberculoid leprosy -- strong Th1 mediated response (IL-2, IFN-gamma and IL-12) this limits the disease extent and causes a small number of hypopigmented, well demarcated plaques with decreased sensation lepromatous -- inability to mount a cellular response -- accumulation of acid fast bacilli in macrophages with TH2 - IL-4,IL-5, IL-10

West Nile Virus

positive, single strand RNA flavivirus transmitted by mosquitos neuroinvascive -- hx of malignancy or organ transplant 1. meningitis/encephalitis 2. asymmetric flaccid paralysis - parkinsonian features

Patient with preeclampsia (high BP and proteinuria or signs of end organ dysfunction). What causes vision loss.

preeclampsia occurs due to abnormal placental development --- high resistance, low perfusion vessels and subsequent placental ischemia triggers widespread endothelial dysfunction -- causes dysregulated vascular tone (vasospasm, vasoconstriction), increased vascular permeability and decreased end organ perfusion Classically presents with HA and visual changes (due to retinal artery vasospasm and optic nerve ischemia)

Patient with 2 months of fatigue and persistent, nonproductive cough. hx of melanoma and 50 pack year smoking. CXR with multiple lung lesions and hilar lymphadenopathy.

presense of brown pigment (melanin granules) in the cytoplasma of atypical cells is indicative of melanoma recurrence. positive immunohistocehmistry for S100 and HMB-45 mealonma often metastasizes early in the disease course so recurrance by occur after years.

Posterior Urethral valves

present with bilateral hydronephrosis and calcyceal dilation due to obstruction of urine flow in the urethra results from the malformation of the Wolffian duct, therefore only present in males

Pure red cell dysplasia

presentation: anemia with normal cell lines path: inhibition of erythropoietic precursors and progenitors by IgG antibodies or cytotoxic T lymphocytes associated with thymomas and lymphocytic leukemias

Patient with a single large mass in the parenchyma of the brain and AIDS?

primary CNS lymphoma

What does MEN type 1 have?

primary hyperparathyroidism pituitary tumors - prolactin, visual defects pancreatic tumors - gastrinomas *most commonly will have hyperparathryoidism with secondary hypercalcemia

Increased activity of a specific intracellular enzyme makes most susceptible to developing benz(o)pyrene induced lung cancer?

pro-carcinogens are metabolized by ctochrome P450 monooxygenase - an enzyme system present in hepatic microsomes and the ER of other tissues. Cytochrome P450 monoxygenase metabolizes steroids, alcohol, toxins and other foreign substances by rendering them soluble and easier to excrete

How is rabies prevented?

prophylactic vaccination for those at high risk using an inactivated vaccine

How does propofol distribution occur?

propofol is highly lipophilic 1. central compartment - plasma 2. well-perfused peripheral compartment -- quickly redistributes due to increased lipophilicity of the tissues compared to the blood (brain, liver, kidneys, and lungs) 3. over time, drug will redistrubut into the poorly-perfused peripheral compartment - skeletal muscle, fat, and bone which has the highest volume of distribution for lipophilic agents. this is rapid and responsible for the short duration of action for such agents

What is the difference between cardioselective and non cadioselective beta blockers

propranolol and nadolol are non-cardioselective and are contraindicated in patients with underlying COPD metoprolol, atenolol, bisoprolol and nevbrivolol are safe

the afferent artiole is primarily controlled by what?

prostaglandin synthesis which is regulated by ibuprofen and calciuneurin

Patient with sclerotic bone lesions on x-ray. What is the dx?

prostate cancer

What does lopinovir do? side effects?

protease inhibitor in HIV, prevents the formation of mature viral proteins SE: 1) lipodystrophy -- increased fat deposition on the back and abdomen and decreased adipose tissue on the face, extremities and buttocks -- creates a buffalo hump 2) hyperglycemia 3) inhibition of CYP450

What causes the contractile motion in skeletal muscle?

proteins myosin II, actin, tropomyosin, and troponin in addition to ca ions

Naegleria fowleri presentation

protozoan parasite found in water -- exposure through recreational water avtivities will penetrate the olfactory mucosa and cross the cribriform plate to invade the olfactory bulb acute confusion, high fever, photophobia and meningeal symptoms

How can you tell a proximal or distal occlusion apart in the LAD?

proximal occlusion - involve V1-V4 distal occlusion will spare the septal leads V1-V2

Patient with distal ureteral ischemia. What likely allows for proximal perfusion?

proximal ureter blood supply comes from the renal artery.

What gram negative rod that does not ferment lactose can cause UTIs?

psudomonas

Pathology of GBM

psudopalisading necrosis with capillaries at the peripher (vascular proliferation)

How do we respond to acute Hep B infection

pts exposed to HBV -- resolution of acute infection is mediated primarily by polyclonyl cytotoxic T cell response

Patient with left sided heart failure. What lung changes would most likely be present?

pulmonary edema impaires ventilation and causes intrapulmonary shunting. makes the lung heavy and stiff, restricting pulmonary expansion during inspiration. decreased lung compliance can mimic that seen with other causes of restrictive lung physiology

What happens in interstial lung disease that will increase in the lung tissue?

pulmonary fibrosis with thickening and stiffening of the pulmonary intersitium. this causes increased lung elastic recoil and airway widening due to increased outward pulling (radial traction) by the surrounding firbotic tissue. This results decrease in airflow resistance that leads to supernormal expiratory flow rates (higher than normal when corrected for lung volume)

Patient with acute onset right sided weakness and slurred speech. Lethargic with right hemiparesis and lower facial weakness, right hemisensory loss and dysarthria. NonconCT with injury to putamin. What artery?

putaminal hemorrhages almost alway affect the adjacent internal capsule -- dysarthria, contralateral hemiparesis and contralateral hemisensory loss. lenticulostriate arteries due to hypertensive vasculopathy

Need to treat homocystinuria how?

pyridoxine (B6) and can also reduce methionine

Malignant hypothermia

rare, autosomal dominant uncontrolled calcium from the SR -- increasing muscle ton (myoclonus, rigidity, hyperthermia) anesthetics cause this - halothane, succinylcholine

DRESS syndrome presentation

reaction to drug (anticonvulsants -- phenytoin, carbamazepine -- allopurinol, sulfonamides and antibiotics) fever, generalized lymphadenopathy, facial edema, diffuse mobiliform rash -- confluent erythema wil follicular attenation eosinophila, atypical lymphocytes and elevated ALT

Herpes Zoster Ophtalmicus

reactivation within the trigeminal ganglion -- affects the ophthalmic division of trigeminal nerve -- developement of a vesicular rash V1 leads to sensory innervation of the cornea -- acute keratitis and hutchinson sign because of subsequent eye involvement

How does the hepatitis B vaccine work?

recombinant HBsAg to generate protective immunity against the virus collection of envelope glycoproteins found on the surface of HBV -- these are made to mediate the attachment of the virus to hepatocytes and subsequent viral entry

Pathogenesis of CF sweat glands

remember these are opposite then other mucosa normally reabsorb Cl and Na from sweat to make it hypotonic. In CF, patients cannot reabsorb and secrete a sweat with high sodium and chloride levels. This would make the pt hyponatremic and cause lethary and vomitting

Pathogenesis of viridans streptococci?

remember this must occur on injured valves viridans produce and extracellular polysaccharide (using sucrose) called dextrans. these bind to fibrin and platelets that are exposed at the sites of valuvlar lesions

What does exposure to ACE inhibitors in infancy cause?

renal dysplasia -- will see pulmonary hypoplasia, limb contractions, growth restriction or cord compression

Acyclovir SE?

renal toxicity

Patient with membranous nephropathy, flank pain, hematuria and left varicocele. What is the dx and why?

renal vein thrombosis due to nephrotic syndrome antithrobin II can lead to a hypercoaguable state which manifests RVT sudden onsent adbominal or flank pain and gross hematuria with elevated LDH due to renal infarction commonly will see left sided varicocele in healthy pubertal men

Presentation of intermittent explosive disorder?

repetitive outbursts of impulsive aggression - disproportionate to the situation uncontrollable impulses to be verbally or physically aggressive

How does skeletal muscle regulate contraction?

responds to beta receptor and epinephrine to increase PK. but also responses to the release of calcium to increase glycogen phosphorylase kinase

Primary Biliary Cholangitis

results in hypercholesterolemia due to leakage of bile back into the circulation --> formation of xanthelasma

How does SVC syndrome present?

results when the superior vena cava is obstructed, so would see signs and symptoms of SVC syndrome that are similar to just a brachiocephalic obstruction, except that both sides of the fave, neck, and chest would be involved

Patient is 17 yo boy with poor vision at night and loss of vision in the midperiphery. bilateral optic disc pallor, attenuation of retinal vessels and areas of dark discoloration.

retinitis pigmentosa genetic dystrophy progressive retinal degeneration (photoreceptors, pigmented epithelium) loss of rods: night blindness, peripheral visual field loss loss of cones: decreased central visual acuity retinal vessel attentuation - due to altered metabolic demand optic disc pallor - optic nerve atrophy and gliosis pigment accumulation - characteristic bone-spicule pattern around vessels

Patient with intestinal like gastric cancer (ulcerated mass with irregular folded or heaped up edges), characterized by glandular structures containing intestinal like columnar cells. What are risk factors?

salt-preserved foods nitrosamine containing componds and chronic H pylori obesity autoimmune atrophic gastritis

What are the side effects of Resperidone

second generation antipsychotic that can cause weight gain and hyperprolactinemia

Metyrapone stimulation test

sensitive indicator of HPA axis integreity blocks cortisol synthesis by inhibition 11-beta-hydroxylase which converts 11-deoxycortisol to cortisol in the zona fasiculata. this lacks glucocortiocid activity but it does not inhibit pituitary ACTH secretion. if the HPA axis is intact, then will see a rise in response to metyrapone and ACTH levels

What will diffuse esophageal spasm present like on manometry?

several segments of the esophagus contract inappropriately at the same time -- disorganized, non-peristaltic contracts on esophageal manometry and corkscrew esophagus on barium esophagogram path: impaired inhibitory neurotransmission within the esophageal myenteric plexus

Acute Hepatitis B

sexual transmission pt with serum sickness like syndrome - joint pain, lymphadenopathy, pruritic urticarial vasculitis rash with RUQ pain elevations is AST and ALT poor prognosis if have a prolonged PTT

Layers that you go through for a cricothyrotomy?

skin, superficial cervial fascia (increased the platysma), investing and pretrachial layers of the deep cervical fascia, cricothyroid membrane

Non-REM Related Parasomnias

sleepwalking and sleep terrors occur during deep, slow wave sleep - usually more common in the first half of the night delta waves - <4HZ

What does Histoplasma look like on a light microscope?

small ovoid bodies within a macrophage -- because it replicates in the phagosome of macrophages if impaired immunity - at risk for dissmeination through the reticuloendothelial system to due to the organisms affinity for mononuclear cells

In DM neuropathy, what fibers can be involved?

small-fiber injury -- predominance of positive symptoms (pain, parethesias, allodynia) large fiber involvement -- negative symptoms (numbness, loss of proprioception and vibration sense, sensory ataxia (positive rhomberg sign), diminished ankle reflexes degeneration of motor axons -- unbalanced strength in the extremities and hammer or claw toe deformities autonomic neuropathy - gastroparesis, orthostasis, neurogenic bladder, erectile dysfunction

What is the role of the smooth ER?

smooth ER is inovlved in the synthesis and processing of hydrophipid compounds - like lipids, phospholipids and cholesterol derivatives (steroid hormones)

Pathogenesis of Borrelia burgdorferi in lyme disase.

spirochete EM -- due to B burgdorferi spreading through the dermis --> annular lesion with central clearing

Where are the watershed areas of the colon?

splenic flexure and rectosigmoid

gastric varices in a patient are usually do to what?

splenic vein thrombosis or portal HTN short gastric veins drain the fundus of teh stomach into the splenic vein - only a splenic vein thrombosis could increase the pressure to cause gastric vericies only in the fundus

Patient with a mass in the anterior cervical lymph node. Where is the cancer? Explain his middle ear effusion?

squamous cell carcinoma originates in the head and neck will first spread here unilateral middle ear effusion suggest obstruction of the eustachian tube -- eustacian tube dysfunction can be due to anatomic obstruction form a mass in the nasopharynz or due to infections

Patient with muscle tenderness and weakness and taking a statin has what? what predisposes to this?

statin myopathy metabolized by CYP3A4 inhibited by macrolide antibiotics, also ketoconazole, non-dishydropyridine calcium channel blockers, amiodarone and protease inhibitors pravistatin is not metabolized the same way

What matters in calculating the maintaince dose?

steady state plasma concentration drug clearance

What is the mechanism of action for bisacodyl?

stimulant laxative stimulates the enteric nerves within the colonic myenteric plexus -- increases peristalsis and enhances colonic motility similar to senna

What is thyroid dermopathy? When will it appear?

stimulation of fibroblasts bt the TRAb and activated T cells -- excessive production of glycosaminoglycans and adipogenesis this causes skin thickening and induration over the shin -- pretibial myxedema Note: graves ophthalmopathy occurs similarly because of expansion of the retro-orbital tissues being displaced forward

True vocal cords

stratified squamous epithelium therefore these are the ones most likely to be infected by HPV -- respiratory papillomatous causes weak cry, hoarseness, and stridor

Necrotizing Fasciitis bugs

streptococcus pyogenes, staph aureas, and clostridium perfringens (also strep agalactiae and aeromonas hydrophilia strep pyogenes is the only one that is PYR positive - wide zone of beta hemolysis

Women with stress urinary incontience. What do kegel excersises do?

stress urinary incontinence is due to urethral hypermobility the results in incomplete closure of the urethra and bladder neck against the anterior vaginal wall involuntary urine loss with increased intraabdominal pressure and no bladder contraction treatment using dietary fiber to prevent straining and uretheral support using pelvic floor exercises (Kegel excersises)

What is somatomedin C?

structurally similar to insulin -- also called insulin like growth factor -- released in response to growth hormone and stimulates growth in target cells

What does statistical power mean? How do you calculate it?

studys ability to detect a difference when one does exist. the probability of rejecting the null hypothesis when it is truly false (the probability of finding a true relationship) power = 1-beta

Patient with painful enlargement of the thyroid gland. What is dx and histo?

subacute granulomatous thyroidits - onset after a viral illness -painful -transient hyperthyroid symptoms increased ESR and CRP, decreased readioiodine uptake inflammatory infiltrate with macrophages and giant cells

Patient with motor fluctuations. Where could inhibition of neurons using stimulation be helpful?

subthalamic nucleus and globus pallidus internus high frequency firing inhibits firing of these nuclei and this results in thalmo-cortical disinhibition.

Patient with HTN, hematuria and moderate proteinuria. microscopy with linear depositis of immunoglobulin and completment along the GBM.

suggestive of nephritic syndrome. suggestive of goodpastures syndrome which is a rapidly progressive cresenteric glomerulonephritis

Patient with a fluid filled cavity in the liver in conjunction with fevers, chills and right upper quadrant abdominal pain.

suggests an hepatic abscess gain access by: 1. biliary tract infection (ascending cholangitis) 2. portal vein pyemia 3. hepatic artery 4. direct invasion from and adjacent source - enteric gram negative bacilli and enterococci 5. penetrating trauma or injury staph aureus can cause hepatic abscesses via hematogenous seeding of the liver. enteric bacteria can cause hepatic abscesses by ascending the biliary tract, portal vein puemia or direct invasion from an adjacent area

Which nucleus regulates the circadian rhythm and pineal gland function?

suprachiasmatic nucleus

Patient with positive "empty can test"

supraspinatous tendon injury most commony affected in rotator cuff syndrome - vulnerable due to chronic repeated trauma from impingement between the head to the humerous and acromion during abduction empty can supraspinatus test -- abduction of the humerus in parallel to the axis of the scapula while in full internal rotation.

Rheumatoid arthritis presentation

swelling & morning stiffness in multiple joints small joints (PIP, MCP, MTP) but NO DIP systemic symptoms cervicial spine involved: subluxation and cord compression

Patient with acute salicylate intoxication. What will you see on the blood gas.

sxs: N/V, dizziness, confusion, tinnitis, fever and tachypnea 1. primary respiratory alkalosis - salicylates stimulate the medullary respiratory cente -- increased ventilation and loss of CO2 in the air 2. primary anion gap metabolic acidosis -- toxic salicylate levels increase lipolysis, uncouple oxidative phophorylation, and inhibit the CAC -- increase in organic acids that increase the anion gap. can have a pH almost in the normral range -- d.y low serum HCO3- and low PaCO3 due to respiratory compensation PaCO2 is lower than what would be expected for respiratory compensation along

Psuedocholinesterase deficiency

sxs: prolonged muscle weakness after receiving succinylcholine genetics: AR, BCHE gene succinylcholine is rapidly hydrolyzed by plasma pseudocholinesterase -- only a small dose reaches the NM junction. pts with this def cannot metabolize and a lot more gets to the NM junction

What is an aminoacyly tRNA made up of?

tRNA charged with amino acid - 3' CCA tail - T loop with ribothymidine, psuedouridien, and cytidine residules - D loop rich in dihydrouridine residues - anticodon loop

What are common causes of referred ear pain?

tempromandibular joint disease, dental disease, or cancer affecting the tongue base, hypopharynx of larynx

Patient with easy bruising. hx of Crohn disease with partial resection. What is the most likely dx?

terminal ileum of the bowel is frequently involved in Crohn disease. bile acids are absorbed in the terminal ileum, recycled in the liver and reused in the absorptive process loss of bile acids causes fat malabsorption and leads to deficiencies in fat soluble vitamins (A,D,E,K) lack of K messes with the coagulation cascade

What is use dependence?

the idea that the faster the heart rate, the more time the Na channels spend in the open and inactivated states and can therefore be blocked by the drug

What are Ladd's bands in malrotation

these obstruct the second part of the duodenum -- cause intestinal obstruction in the process -- leads to billious emisis this twisting occurs around the superior mesenteric artery

If aortic stenosis is severe, then what happens?

they have a characteristeric arterial pulse - small pulse amplitude (pulsus parvus) and a delayed peak and slower upstroke of the arterial pulse (pulsus tardus) -- due to diminished stroke volume and prolonged ejection time

Patient with maple syrup urine disease. What should be supplemented?

thiamine supplementation due to defective breakdown of branched chain alpha-ketoacid dehydrogenase remember this requires the same 5 cofactors as pyruvate dehydrogenase and alpha ketoglutarate dehydrogenase -- thiamine, lipoate, coenzyme A, FAD, NAD

cirrhosis pathology

thickened collagenous bands (stain with Masson trichrome stain) and separate hepatocytes will see fat infiltration in alcoholic and NAFLD in response to injury - stellate cells are activated and transform into myofibroblasts that proliferate, promote chemotaxis and produce collagen in large quantities *when quiescent these cells are a space of vitamin A storage

Sarcomere structure

thin filaments are bound to structure proteins at the Z line -- the unbound actin filaments project into the middle of the sarcomere where they interact with thick myosin filaments during muscle contraction

What does the path of hepatitis look like?

think about this when someone travels to an endemic region spotty necrsosi with balooning degeneration (hepatocyte swelling with wispy/clear cytoplasm), councilman bodies (eosinophilc apoptotoic hepatocytes) and mononuclear cell infiltrates

What is the difference in immune response between cutaneous and disseminated fungal infection?

think of HIV T lymphocytes (Th) - important in superficial infections Neurtrophils prevent the hematogenous spread of Candida - disseminates is much more common in neutropenic patients

Patient with a low-frequency sound occuring after S2. What is it called and what causes it?

third heart sound heard during rapid passive filling of ventricles in diastole -- sudden cessation of filling as the ventricle reaches its elastic limit due to: systolic heart failure, mitral reguritation, and high output heart states

What is myesthenia gravis associated with pharnygeal abnormalities?

third pharyngeal pouch is where the thymus is from usually have a thymoma or thymic hyperplasia

What do you see if there is a large arteriovenous gradient in the blood with an anesthetic?

this is a measure of the solubility of the anesthetic in peripheral tissues -- determines the size of the AV gradient. if high - then a large amount of the anesthetic is taken up into the blood and therefore blood saturation takes longer and brain saturation also takes longer

Patient with spontaneous but painless lower GI bleeding in a child. Could also present with colicky abdominal pain. 99mTc-pertechentate has an affinity for parietal cells and see a spot in the RLQ?

this is a meckel diverticulum which is due to filure of the obliterated vitelline (omphalomesenteric duct)

Patient with a low frequency sound that occurs shortly after S2 during diastole. What is this sound? What causes it to be worse.

this is a third heart sound. due to sudden cessation of filling as the ventricle reaches its elastic limit. heard during passive filling of the ventricles in diastole. usually due to volume overload or enlargement. listening at the end of expieration makes the sound more audible

How does COX2 work?

this is an inducible enzyme -- undetected normall but then in inflammation and in response to cytokines it is expressed (IL-1 and TNF-alpha) then drives synthesis of arachodonic metabolits

When does a preventable medical error happen?

this is anything that involves harm to the patient by an act of commission or omission rather than from the underlying disease - failure to follow evidence based best practice guideleins

Patient with a wide, fixed splitting S2 that does not vary with respiration. What is the dx and what will happen?

this is due to an ASD and delayed closure of the pulmonic valve. pulmonary arteries will be damaged -- they develop laminated medial hypertrophy that is so sever it increases pulmonary cadcular resistance above the total systemic vascular resistance --> leads to Eissenmeinger syndrome

What is the point where the lung and chest wall presures balanced equals 0?

this is the FRC -- the amount of air left at a normal breath

What does it mean to be a superantigen?

this means that it causes nonspecific T cell receptor activation

Think of contrast induced nephropathy when...?

this occurs in someone who had a PCI usually occurs approximately 24-48 hours after getting the injury mechanism: thought to be the direct cytotoxicity of IV contrast of the tubular cells and due to renal vasoconstriction usually will see acute tubular necrosis --> diffuse necrosis of the proximal tubular cells

Inflammation in ankylosing spondylitis?

thought to originate in the gut defects in the mucosal barrier - induces IL-18 mediated response using TH1 and Th17 cells. 17-17 -- stimulates produce of additionally inflammatory factors (TNF-alpha and prostaglandins) --> bony erosions and abnormal bone growth

Pathology of amniotic fluid embolis?

tissue factor is released from amniotic fluid and this triggers DIC. autopsy will show fetal squamous cells and mucin in the maternal pulmonary arteries

Pathogenesis of acute pancreatitis

toxic or ichemic injury to the acinar cells that leads to premature activation of trypsin in the pancreatic acini activates the other proteolytic anzyme -- causes inflammation and autodigesition due to these enzymes. necrotizing pancreatitis is caused

Pathology in vitamin D deficiency

trabecular thinning with fewer interconnections

Patient with uticaria. What is seen on histology?

transient HS with wheals (intensly pruritic, raised erythematous plaques that arise and resolve. caused by IgE mediated degranulation of mast cells edema of the superficial dermis spongiosis - intercellular epidermal edema that appears as an increase in width of spaces between cells -- associated with spngiotic dermtitis

Patient with sickle cell and symptomatic anemia. Also with pronormoblast and cytoplasmic occlusion. What is the dx?

transient aplastic crisis due to parvovirus B19 infection infection of erythroid progenitor cells prevents red blood cell maturation which leads to the formation of abnormal giant pronormoblasts with intranuclear viral inclusions.

What does it mean if a cells is positive for synaptophysin?

transmembrane glycoprotein found in the presynaptic vesicles of neurons, neuroectodermal, and neuroendocrine cells. this indicates neuronal orgin. GRAP will be positive for astroctyomas - GBM, oligodendrogliomas and ependymomas and peripheral nerve sheath tumors

When would a mutation in bacterial efflux proteins cause resistance to antiboitics?

transmembranous efflux pumps confer resistance to antibiotics that would need to enter the cell (tetracyclines and macrolides). penicillins and cephalosporins will not develop resistance in this way.

How do leukotriene receptor antagonists function?

treat asthma by biding to leukotriene receptors on bronchial smooth muscle cells and blocking the effects bind to the CYST receptror on LTD4

Foscarnet use and SE?

treatment of CMV infections nephrotoxicity and electrolyte disturbances - hypocalcemia, hypomagnesemis, hypokalemia

Pathology of carotid sinus hypersentitivity

triggered by pressure on the carotid sinus -- regulate blood pressure control and use arterial wall stretch as an indicator for systemic BP afferent limb -- uses the glossopharengeal nerve. efferent limb uses the vagus nerve.

What is the pathogenesis of hepatic steatosis?

triglyceride accumulation within the hepatocellular cytoplasm. decrease in fatty acid oxidation secondary to excess NADH production by the 2 major alcohol metabolism enzymes (alcohol dehydrogenase and aldehyde dehydorgenase) impaired lipoprotein secretion and assembly and increase in peripheral fat catabolism

Where does a pheochromocytoma originate from?

tumor of the chromaffin cells of the adrenal medulla - characterized by excess production of catecholamines will be synaptophysin, chromogranin, and neuron-specific enolase positive. EM shows dense membrane boung granules with catecholamines

Toxoplasmic encephalitis

typically in an HIV positive patient with CD4 less than 200 seizures, multiple ring enhancing lesions

Where can uracil and thymine be found?

uracil will only occur in the mRNA transcript (not the DNA) so it cannot be changed in the DNA itself

what do you use vimentin for in tumors?

use this to differentiate cells of mesenchymal orgina

Findaxomicin

used for c. diff infection macrocylic antibiotic (similar to a macrolide) inhibits the sigma subunit of TNA --| protein synthesis and causing death

when do you use matching in a study?

used in case-control studies to control for confounding

Cellular immune response to a viral pathogen requires the presentation of viral antigens to effector immune cells. How does this happen?

uses the ubiquitin proteasome pathway -- role in breaking down native and foreign intracellular proteins. ubiquitin ligase initiaties the UPP by recognizing specific protein substrates and catalyzing the attachment of ubiquitin. tagged proteins are the broken down by a proteasome to peptide fragments. peptide fragments in this process are couple to MHC class I molecules in the ER --> presented to the cell surgace CD8 T cells trigger apoptosis of the cell by activating the caspase cascade through the release of perforin and granzyme

Presentation with a painful eye lesion?

usually glaucoma

hyperacute

usually on the first day of transplant - preformed host antibodies against donor ABO or HLA path: fibrinoid necrosis with hemorrhage and ischemia

What medication should be given to patients who present with bradycardia and inferior MI?

usually this will lead to SA and AV node dysfunction (and bradycardia) because RCA is occluded thus will need to give them atropine to increase the heart rate *atropine can precipiate glaucoma because it causes mydriasis

Irriation of what nerve near the hypopharynx causes ear pain?

vagus n. -- has afferent fibers that innervate the larynx and hypopharnyx * also does this with the glossopharyngeal nerve that innervates the upper pharynx and base of tounge

Exercise Cardiovascular Changes

vasoconstriction of capacitance veins leads to increased venous return (increased preload) which shifts LV end diastolic volume to the right) vasoconstriction of the splanchnic circulation and a higher degree of vasodilation in skeletal muscle -- shunts blood to the skeletal muscle and causes overall reduced SVR --> increased preload by allowing cardiac output to return to the right atrium more quickly and easily myocardial contractility is increased --> increased SV increase in afterload doue to increased peak LV and aortic pressure during LV contraction

normal response to excessive heat includes

vasodilation of the skin vessels (peripheral vasodilation) and vasoconstriction of the splanchnic vasculature

Acute mitral regurgitation findings

very high LA pressures and pulmonary edema increased preload b/c the LV must hold regurgitant blood and normal decreased LV afterload because there is a low resistance regurgitant pathway decreased afterload means there is an increased SV so the LV ejection fraction increases

Outbreak of a diarrheal illness in a community after a hurricane. Community experiences voluminous, watery, diarrhea that quickly leads to severe dehydration. See oxidase positive, curved, highly motile gram negative rods.

vibrio cholera comma-shaped, oxidase positive, highly motile gram negative rod acid sensitive - a high burden is needed to cause clinical symptoms *if inadequate gastric acid production (achlorhydria) can develop the disease with a much smaller infectious dose. This is true for patients on long-term PPI therapy

Patient with exertional dyspnea, fatigue, conjunctival pallor and a systolic ejection murmur that has symptomatic anemia. Peripheral blood smear with hypersegmented neutrophils and macrocytosis. What is the dx?

vitamin B12 deficiency -- this (with folate deficiency) impair DNA sysnthesis and cause cell death. increased apoptosis will cause the anemia and often a dmild thrombocytopenia and leukopenia

If a patient decides to be vegan, what vitamins should they replace?

vitamin B12, vitamin D, calcium maybe - iodine, iron, and zinc

Patient presents with photosensitive dermatitis, diarrhea and dementia. What is the cause? what reactions are at risk?

vitamin B3 (niacin) deficiency NAD and NADP reactions isocitrate dehydrogenase

Patient with pyruvate dehydrogenase deficiency. A diet high in what AA should be given to them?

want a ketogenic amino acid diet - ketogenic amino acid metabolism generates the ketone body precursor acteyl-CoA lysine and lucine are exclusively ketogenic AA Glucogenic amino acid metabolis produces pyruvate or TCA cycle intermediates -- converted to glucose via gluconeogeneisis (alanine and serine)

Child with Tetralogy of Fallot. what is he dependent on?

when the pulmonary stenosis is severe, dependent on the PDA for adequate oxygenation because the ductus arteriosis allows blood flow to go from the aorta to the pulmonary vascular bed. Maintain this with prostaglandin E2.

In SIBO, what will generally increase and why?

will have an increase in vitamins - vitamin K and folate because the enteric bacteria produce vitamins will see decrease in cobalamin (vitamin B12), iron, fat soluble vitamins, and zinc

Acute rejection presentation

within 6 months cell mediated immune reponse to donor human leukocyte antigens perivascular mononuclear infiltrates in the small vessels that can expand to the walls of the alveoli

Where does verapamil work on the cardiac action potential?

work by blocking the L-type calcium channels in cardiac slow response tissues which causes slowing of the phase 4 depolarization and reduced conduction velocity in the SA and AV nodes

In the setting of PE, what do the blood gasses look like?

would expect to see a low PaO2 because of V/Q mismatch. then will see hyperventilation (this will not fix the O2 saturation) but will drop the Co2 (because it diffuses better) -- causes respiratory alkalosis. metabolic compensation (by dropping HCO3-) is not expected in acute settings

fetal autopsy shows microcephaly with tin cerebral cortices, ventriculomegaly and subcortical calcifications

zika virus single-stranded RNA, flavirus Aedes mosquito destroys fetal neural progenitor cells

What does it mean if someone is hipoxic and does not respond to O2

-- means that there is a shunt in their system (foreign body blocking oxygenation

How to reduce malpractice liability from treatment complications?

-acknowledge errors openly -do not hide errors or other relevant factors -express empathy and give apology as appropriate -avoid blaming or denigrating other team members and providers -allow adequate opportunity for patient questions follow up by: - remain engaged in the patient's care - outline steps to prevent future occurance

anorexia nervosa symptoms and dx

-restricted energy intake with a significantly low body weight (BMI is less than 18.5) -intense fear of becoming fat or persistent avoidance of weight gain -distorted body image complications - osteoporosis, amenorrhea, lanugo or hair loss, parotid hypertrophy, hypotension, hypothermia, bradycardia, cardiac atrophy and arrythmias

Where do raloxifene and tamoxifene work?

1) raloxifene is an estrogen agonist in the bone (decreases bon resorption, improves density, decreases fracture risk), antagonist in the breast and uterus to decrease risk of cancer 2) tamoxifene - estrogen antagonist activity in the breast and agonist in the bone and the uterus (which makes it not appropriate for osteoprosis)

Two mechanism of increased bilirubin

1. increased production due to breaking it down over time -- seen in sickle cell anemia 2. altered enterohepatic circulation - ileal disease or resection allows bile that was normally reabsorbed in the ileum to spill into the color -- there they solubilize unconjugated bilirubin and allow for reabsorption

How does insulin signaling work?

1. increases glucose uptake into skeletal muscle cells and adipocytes 2 promotes synthesis of glucagon, triglycerides, nucleic acids and proteins 3. inhibits glycogenolysis and gluconeogenesis transmembrane protein with intrinsic tyrosine kinase activity in cytoplasmic domain. phosphorylates IRS-1 --> activates MAPK for DNA synthesis and cell growth activates PI3K to stimulate metabolic functions -- GLUT-4 to the cell membrane, glycogen synthesis and fat synthesis. promotes glycogen synthesis by activate a protein phosphatase that dephosphorylates glycogen synthase and leads to is activaiton

Digoxin Mechanism of Action

1. inhibits the Na/K ATPase pump in the myocardial cells, this leads to decreased sodium efflux and therefore increased intracellular sodium levels. 2. secondary decrease in calcium efflux due to the increased amount of Ca causes: binding of calcium to troponin C and subsequence actin - myosin cross bridge formation -- improves myocyte contractility

What is the function of the CNVII nerve and how does Bells Palsy present?

1. motor output to the facial muscles 2. parasympathetic innervation to the lacrimal, submandibular and sublingual salivary glands 2. special afferent fibers for taste from the anterior 2/3 of the toungue 4. somatic afferents from the pinna and external auditory canal unilateral facial paralysis -- impaired eye closure, eyebrow sagging, inability to smile and frown, disappearance of the nasolabial fold and mouth being drawn to the nonaffected side decreased tearing, hyperacusis and loss of taste over anterior 2/3

Cellulitis classifications

1. nonpurulent cellulitis - skin warmth, edema and erythema with no fluctuant nodules -- most common beta hemolytic strep, usually group A strep (strep pyogeneous) 1. purulent cellulitis - painful, fluctuant nodule in the dermis or subcutaneous tissue with or without surrounding erythema -- strep

Kidney Embryonic Development Steps

1. pronephros - forms and disinegrates 2. mesonephros - interium kidney and contributes to the male developmental system (female regresses) 3. metanephros (week 5 to 32-36) *uteric bud -- ureter, pelvises, calyces, collecting ducts *metanephric mesenchyme -- glomerulus through the DCT

What happens in the kidney due to aging?

1. reduced renal mass and functional glomeruli - this results in a reduced GFR and creatinine clearance and a reduced ability to concentrate urine 2. reduced renal blood flow - loss of renal microvasculature results in a reduction of renal blood flow with age - renal blood flow becomes more depedent on prostaglandins to maintain adequate blood flow -- increased susceptibility to renal injury with NSAIDs 3. reduced hormonal responsiveness - reduced secretion of renin and reduced hydroxylation of vitamin D in response to PTH production of EPO remains unchanged

How do you recognize tRNA? What are the specific regions in this molecule?

1. tRNA is a small noncoding RNA that contains chemically modified bases - dihydrouridine, ribothymidine, and pseudouridine acceptor stem - base paining with teh 5' and 3' nucleotides 3' CCA tail - add to the 3' end of the tRNA as a post transcriptional modification in eukaryotes -- has the 3' terminal hydorxyl group. D loop - facilitates correct tRNA recognition by the proper aminacyl tRNA synthetase Anticodon loop - complementary to the mRNA codon T loop - sequence that is neccessary for binding of the tRNA to ribosomes

Patient with preeclampsia. What is the response of her kidneys with respect to specific gravity, proteinuria, and RBCs?

1. third apcing and vasoconstriction of renal vesels results in decreased urine production and concentrated (increased specific gravity) because the kidneys are trying to retain sodium and water. 2. damage to the renal endothelium increases glomerular permeability and allows for leakage of large moelcules as evidenced by proteinuria 3. renal vasoconstriction causes a decreased GFR and increased serum creatinine - healthy pregnant patients have decreased baseline serum creatinine levels due to blood volume expansion and increased GFR -- normal appearing is bad.

What does vWF do in the platelet plug?

1. vWF promotes platelet adhesion at sites of vascular injury by binding to and crosslinking platelet glycoproteins (using GpIb) with exposed collagen under the damaged endothelium. 2. protective carrier protein for factor VII that increases the half life

Attributable risk percent in the exposed

100 x (RR-1)/RR represent the excess risk in the exposed population that can be attributed to the risk factor

How to calculate the SD

68, 95, 99.7% rule note this is the total amount outside, so would need to divide in half to just get the above or below

Partial Molar Pregnancies

69, XXX or 69, XXY - result of an ovum being vertilized by 2 sperm contain fetal tissue with normal placental villi intermixed with hydrophic villi

Patient was started on an ACE inhibitor and now has hypertension. Also takes NSAIDs. What is the cause?

ACE inhibitors cause first-dose hypotension --> limiting factor when initiating ACE inhibitors usually in patients with volume depletion from other diuretic use or HF ACE inhibitors cause the abrupt removal of vasoconstrictive effects of angiotensin II --> decreased peripheral vascular tone and a percipitous drop in BP

Patient with memory loss of recent events and other executive dysfunction (difficulty planning and organizing) and visuospatial impairment (getting lost in one's own neighborhood). What is the dx and what is seen on bx?

AD amyloid plaques and neurofibrillary tangles neuritic senile plaques are extracellular deposits in the medial temporal lobe (hippocampus, amygdala, entorhinal cortex) and have central amyloid beta core surrounded by dystrophic neuritis. this is toxic to neurons and is thought to occur secondary to impaired clearance and overproduction of amyloid precursor protein. Neurofibrillary tangles are found in the neuronal cytoplasm -- aggregates of hyperphosphorylated Tau protein which mediates microtubule stabilization

What is the cause of acute intermittent porphyria? tx?

AD prophobilinogen deaminase deficiency tx: infusion of hemin -- downregulates the aminolevulinate synthase

When does autosomal dominant PKD present and with what other symptoms?

AD microscopic cysts at birth are too small to be detected by abdominal ultrasound HTN with increased renin secretion, berry aneurysms and MVP, hepatic cysts

Patient with hypertrophic cardiomyopathy. what is the pathology of his outflow obstruction?

AD sarcomere proteins systolic anterior motion of the mitral valve toward the interventricular septum -- mitral regurgitation and makes it worse PE: harsh crescendo - decrescendo murmur at the apex and left sterol border

In huntington disease, how does the mutation occur?

AD neurodegenerative disease -- increased number of CAG trinucleotide repeasts in huntingtin -- gain of funcation that leads to bad interaction with other proteins transcriptional pression is one of the mechanisms by which it works increases histone deacetylation --> silencing the genes neccesary for neuronal survival.

What enzyme will be reduced in a patient taking isonazid and presenting with anemia and ringed sideroblasts?

ALAS because it requires vitamin B6 as its cofactor iron is still transported to the developing erythrocytes and will form around the nucleus ringed sideroblasts (this is iron in the mitochondria

What is Alkpatonuria described as?

AR deficiency in homogentisic acid dioxygenase -- normally metabolizes homogentisic acid into maleylacetoacetate depostis in connective tissue in the body -- black/blue deposits become apparent in the slcearae and ear cartialge urine of these pts turns black when exposed to air due to oxidization of homogentisic acid

Galactosemia

AR galactose -1-phosphate uridyltransferase deficiency. galactose comes from normal breas milk and regular infant formula sxs: neonatal jaundice, cataracts, hepatomegaly and E Coli sepsis. tx: dietary restriction of galactose

Maple Syrup Urine Disease

AR branched chain alpha ketoacid dehydrogenase complex deficiency normally allows for the breakdown of leucine, isoleucine and valine sxs: neurotoxic due to elevate leucine. irritibility, poor feeding, lethargy and increased muscle tone. urine with maple syrup odor tx: dietary restriction

What type of channel is the CFTR channel?

ATP gated channel

Patient with a fib and RVR. What to ablate to treat the RVR. What would you ablate and where?

AV node - because this controls the rate at which atrial impulses are conducted to the ventricles AV node is located on the endocardial surface of the right atrium near the insertion of the septal leaflet of the tricuspid valve and the orifice of the coronary sinus

Patient with poor weight gain and normal intestinal mucosal architecture, but will clear or foamy cytoplasm. What is the dx?

Abetalipoproteinemia - impaired formation of apoB containing lipoporteins AR loss of function mutation in the MTP gene labs - low plasma triglyceride and cholesterol levels and chylomicrons, VLDLs and apoB are absent from the blood causes a deficiency of fat soluble vitamins and essential fatty acids -- red blood cells with abnormal membranes and thorny projections called acanthocytes and multiple neurologic abnormalities

42 yo women with heavy, painful menstrual bleeding. Uterus is uniformly enlarged. What does she have? What is the path?

Adenomyosis endometrial tissue in the myometrium not - leiomyomas the uterus would be irregularly enlarged

Patient with an SVT is administered a drug that treats arrythmia, but develops flushing, chest pain, and hypotension. Which drug was administered?

Adenosine increases K+ out of cells, hypepolarizing the cell and decreasing CA. leads to a decreasing AV node conduction.

Patient who recently started taking NSAIDs and presents with increased serum creatine, mild proteinuria and evidence of tubular dysfunction.

Analgesic nephropathy - microscopic hematuria and sterile pyruri prolonged use of NSAIDs results in chronic interstitial nephritis -- patchy interstitial inflammation with subsequent tubular atrophy and fibrosis, papillary necrosis and scaring. kidneys will appear shrunken with irregular contours and distortion of the calciceal architecture. NSAIDs cause decreased prostaglandin synthesis --> renal vasoconstriction with further increases the risk of ichemic papillary necrosis

Patient with advanced CKD disease. What type of acidotic derangement is expected?

Anion gap metabolic acidosis with respiratory compensation

Difference between anorexia and bullemia?

Anorexia results in significant low body weight - distorted body image and fear of weight gain can have a binge subtype that is NOT bullemia -- would see hypokalemia and alkalosis parotid swelling just indicates purging and is not specific to bullemia

Patient with a new holosytolic murmur (think MR) Pathoneumonic finding in rheumatic fever?

Aschoff body - interstital myocardial granuloma Anitschkow cells - plump macrophages with abundant cytoplasm and central, slender chromatin ribbons

Patient with recurrent transient pulmonary infiltrates. Patient with proximal bronchiectasis and eosinophilia. What organism is causing this disease?

Aspergillus Fumigatus asthma, CF recurrent fleeting infiltrates with bronchiectasis on CT scan Allergic bronchopulmonary aspergillosis -- occurs in 10% of corticosteroid dependent asthmatics very high IgE levels, eosinophilia and IgE serum antibodies to Aspergillus repeated execrations may produce transient pulmonary infiltrates and proximal bronchiectasis

Patient with urinary hesitancy, weakened urinary stream and nocturia in the setting of an enlarges nontender prostate. What causes hematuria?

BPH will see microscopic or gross hematuria --> due to the formation of new, friable blood vessels in the area of prostatic hyperplasia

Patient with hereditary breast cancer history. What does the gene defect do?

BRCA1 and BRCA2 are involved in repair of double-stranded DNA breaks.

Bladder Anatomy

Bladder is an extraperitoneal organ -- this means that in order to get intraperitoneal fluid, must rupture the bladder dome that is attached to the parietal peritoneum

Patient with Huntington disease. What will happen and what is the most specific disease detector?

CAG trinucleotide repeats -- gain of function mutation that leads to the accumulation of abnormal huntington protein in neural crest cells inhibitory GABAergic neurons in the caudate nuclei (striatum) are especially vulnerable and atrophy early in the course of the disease

Patient with Giardia. How does immune system respond.

CD4+ T helper cells and secretory IgA production. IgA impaires adherance to the upper small-bowel mucosal. Children with IgA deficiency, X-linked agammaglobulinemia, and common variable immune deficiency have a predisposition to developing chronic giardiasis

What causes RA pathogenesis?

CD4+ T-helper cell directed against joint components induce the B cells to synthesize rheumatoid factor (igM specific for the Fc component of IgG) and anti-citrullinated protein antibodies

Patient with breast lump receives an inhibitor of cyclin-dependent kinase. What is the dose-limiting toxicity of this medication?

CDK 4/6 inhibitors (palbociclib) can be used to block the cyclin D binding site of CDK, less CDK 4/6 activation and increased activity of the RB tumor suppressor protein and cell cycle arrest. will inhibit cellular replication in other rapidly dividing cells esp in the bone marrow --> neutropenia, leukopenia and anemia

What is the pathogenesis of CKD?

CKD the phosphate clearance declines due to a fall in GFR this increased PO4 binds free serum calcium resulting in hypocalcemia less vitamin D synthesis -- results in decrease in intestinal Ca absorption and Ca release from bone all of this stimulates PTH production

Patient with HIV and abdominal pain, decreased appetitie and diarrhea. BX shows ulcers revealing inflammatory infiltrate, mucosal necrosis and enlarged endothelial cells with large ovoid nuclei containing prominent basophilic deposits. What is the dx?

CMV colitis giant cells with large ovoid nuclei containing centralized intrancuelar basophilic inclusions

fetal autopsy with hearing loss, chorioretinits, jaundice, and periventricular calcifications

CMV virus

What is the diagnostic findings of Naegleria fowleri?

CSF testing is negative for bacterial, viral, or fungal pathogens. wet mount with motile trophozoites Tx: amphoterinicin B

Calciphylaxis

Calcific uremic arteriolopathy occurs with advanced chronic kidney disease and leads to severe skin ischemia and necrosis superficial arteriolar calcification, subintimal fibrosis and thrombosis

Child with 2 days of fever, abdominal pain and diarrhea. New puppy. patients stool is positive for occult blood.

Campylobacter jejuni ingestion of contaiminated food (especially undercooked poultry) but direct contact with domesticated animals is another important source of transmission inflammation (leukocytes, erythrocytes) but no ova and parasites colonizes the intestinal mucosa, enters enterocytes and causes cytotoxic injury

Patient with right hand pain and numbness, thenar atrophy and weakness of thumb opposition. What needs to be transected?

Carpal tunel syndrome between the carpal bones and the transverse carpal ligament (flexor retinaculum) median n. and 9 tendons (fexor digitorum superificialis, profundus and flexor pollicis longus) all pass through increased pressure causes nerve damage

Which if the antifungal medications inhibits cell wall synthesis? How?

Caspofungin - block glucan synthesis (1,3-beta-D-glucan) the polyene and azole antifungals target the fungal cell membrane

Patient with sensory and motor deficits that are not associated with a single peripheral nerve and follow a dermatome. What is the dx?

Cervical radiculopathy usually present with neck or arm pain associated with motor or sensory deficits due to compression of spinal nerve roots spinal spondylosis -- aging leads to degeneration of vertebral bodies, discs and joint subacute onset of symptoms vertebral disc hernitation

Atherosclerosis

Changes in the walls of large arteries consisting of lipid deposits on the artery walls.

Patient with transient febrile illness and rash followed by severe polyarthritis. What is the dx?

Chikungunya fever tropical/substropical parts of Central/South America, Africa, Asia aedes mosquito incubation is 3-7 days, high fevers and sever polyarthralgias lymphopenia, thrombocytopenia and transminitis supportive care can go on to have chronic arthralgias/arthritis which requries methotrexate coinfection with dengue and zika can also occur

Patient with a pearly mass behind the tympanic membrane and hearing loss. What is the cause and pathology?

Cholesteatomas collection of squamous cell debris that form a round, peraly mass behind the tympanic membrane in the middle ear. due to chronic negative pressure in the middle ear --> retraction pockets in the tympanic membrane that become cystic as the squamous cell debris accumulates usually cause conductive hearing loss

What are the risk factors for Barrett esophagus?

Chronic Gerd obesity (increases intragastric pressure, frequency of lower esophageal sphincter relaxation and rates of hiatal hernia which promote GERD) smoking using medications that lower esophageal sphincter pressure (nitroglycerin) consumption of foods containing nitrosos compounds

White coat HTN is an example of what kind of conditioning?

Classical conditioning this is when a previously neutral stimulus elicits and response after association with a neutral, unlearned stimulus

What is the structure of the histone? How is it tightened?

Core is made up of each protein x2 - H2A, H2B, H3, and H4 H1 is located outside of the histone core and binds the linked segments of DNA that lie between nucleosomes to facilitate packaging of nucleosomes.

What would you see in the CSF of a patient who has progressive neurodegenerative disease caused by prions?

Creutzfeldt-Jakob disease 14-3-3 protein in the CSF

When there is methotrexate in the cell, what accumulates and why?

DHF polyglutamate and folic acid because the DHF reductase is not working

Patient with purulent arthritis of the knee, oligoarticular joint pain, and a few vesiculopustular lesion on the extremities. What is dx?

Disseminated gonococcal infection common cause of septic arthritis in young sexually active individuals when spread of Neisseria gonorrhoeae from a asx GU infection into the systemic circulation

What tumor mutation is associated with GBM?

EGFR promotes cellular survival and proliferation

EGFR signaling in colorectal cancers?

EGRF is stimulated in a paracrine or autocrine fashion by ligands --> downstream activation of KRAS (membrane bound GTP binding protein that simulates cellular growth and proliferation) monoclonal antibodies can target EGFR -- reduced KRAS stimulation and decreased cell growth tumors with KRAS activating mutations are resistance to EGFR agents

Travelers diarrhea is most commonly caused by what?

Enterotoxigenic E. Coli - ETEC - developing countries acute onset of nausea, vomitting and watery, nonbloody diarrhea

What is the role of the nucleolus?

FIRST, will see a round, dense basophilic body this is the primary site of ribosmal RNA transcription RNA polymerase I functions exclusively here -- makes the 45S pre-rRNA -- 18S, 5.8S and 28S rRNA NOTE in malignant cells, there is a high metabolic activity so there is a large number of active rRNA genes

Patient with a subcutaneous nodule on the dorsum of his right hand. 2-3 flat subcutaneous nodules on the dorsum of his right hand and a larger nodule at the Achilles tendon area. Father died of a heart attack at an early age. Also with small yellowish papules on his right lower eyelid. What is the dx and what is decreased?

Familal hypercholesterolemia AD defective LDL cholesterol receptor gene excess LDL is deposited in the arteries as atheromas and in the tendons and skin as xanthomas (lipid rich foam cells in the dermis or subcutaneous tissue, present as yellow rubbery nodules and plaques)

Patient with plasma lipoprotein lipase activity measured after IV heparin administration that is lower than normal and milky white plasma. What is Dx and complications?

Familial chylomicronemia syndrome AR LPL deficiency -- cannot clear dietary lipid loads due to defective hydrolysis of serum triglycerides (especially chylomicrons) marked hypertriglyceridemia, recurrent acute pancreatitis, lipemia retinalis (milky appearing retinal vasculature) and erruptive xanthomas (small yellowish papules surround by erythema found on extensor surfaces)

What is condyloma lata?

Flat fleshy warts, ulcerate, 2° Syphilis

Glucose transport proteins types and where they work

GLUT-4 is only responsible to insulin (expressed in skeletal muscle cells and adipocytes) GLUT 1,2,3,5 - responsible for insuline-independent glucose transport 1- erythrocytes and BBB 2 - hepatocytes, pancreatic beta cells and basolateral membrane of renal tubules and small intestinal mucosa 3- placental and neuronal glucose transport 5 - fructose transporter in spermatocytes and the GI tract

Patient with fatigue and abdominal distension. Pallor and ecchymoses on the extremities and massive splenomegaly. Decrease in all cell lines.

Gaucher AR B-glucococerebrosidse deficiency --> accumulation of glucocerebrodise and causes lipid laden macrophages with wrinkled tissue paper in bone marrow

Patient dx with DM 6 months ago and now presents with coalescing erythematous plaques with crusting and scaling at the borders and central areas of brownish induration. What is dx?

Glucagonoma arises from the alpha cells of the pancreatic islets hyperglycemia and overt DM necorlytic migratory erythema -- elevated painful and pruritic rash typically affecting the face, groin and extremities. Small erythematous papules colesce to form indurated palques with central clearing

What antibodies are present in Graves disease? In chronic lymphcytic (Hashimoto) thyroiditis?

Graves: thyrotopin receptor antibodies Hash: Tyroid peroxidase antibody

Which bands change length during muscle contaction?

H and I bands because they are the areas where actin and myosin do not interact

Patient with COPD exacerbation. What is the most likely causitatve agent?

H. Flu also strep pneumo, moraxella catarrhalis and rhinovirus severe COPD more at risk for psuedomonas

What are the major adverse effects of nitrate therapy?

HA, cutaneous flushing, lightheadedness, hypotension and reflex tachycardia avoid in patients with hypertrophic cardiomyopathy (due to increased outflow tract obstruction), right ventricular infarction (due to reduction in preload, impairing cardiac output) and those on phosphodiesterase inhibitors (synergism increases the risk of hypotension)

How does HIV viral entry occur?

HIV attaches to host cells using gp120. this glycoprotein binds to CD4 and CCR5 or CXCR4 as a coreceptor. this induces a confomational change in gp120 that exposes the underlying transmembrane protein gp41 - which mediates viral fusion to the host cell and release of the viral capsid into the cytoplasm if only blocks fusion - then this means it is blocking binding of the chemokine receptor these are the chemokine receptor antagonists - maraviroc and enfuvirtide

TMP-SMX

HIV prevent and treatment of P Carinii megaloblastic anemia, SJS, toxic epidermal necrolysis

what does a child have who is presenting with oral thrush, interstitial pneumonia, and severe lymphopenia in the first year of life?

HIV-1 through vertical transmission prevented by treatment during pregancy - will use 2 NNRTI and a third drug cannot use efavirenz in the first 8 weeks due to teratogenic risk infants should receive many weeks of zidovudine ppx

Child with swollen gums and vesicular, inflammed lesions on his hard palate and lips. also with enlarged and tender cervical lymph nodes. What is the dx and characteristics?

HSV-1 causing gingivostomatitis enveloped and has a double-stranded DNA genome virus replicates in the host cell nucleaus and causes abnormal cell division --results in intranuclear inclusion bodies and multinucleated giant cells that are visible on Tzank smear

Patient with mouth ulcers and vesicular lesions on his hands during the summer and at summer camp. What is the long term sequellae?

Hand-foot and mouth disease caused the enterovirus this has fecal oral tranmission long term could develop myocarditis (congestive heart failure) or CNS disease (aseptic meningitis)

Patient with several months of fatigue and weight loss. Liver bx shows large hepatocytes filled with finely granular, homogeneous, pale pink cytoplasm. What is the dx?

Hepatitis B infection due to chronci infection that leads to accumulation of hepatitis B surface antigen within infected hepatocytes --> finely granular, diffusely homogenous, pale eosinophilic cytoplasm

3 yo with unknown FH and has anemia, reticulocytosis and increased indirect bilirubin. See blood smear with RBCs without central pallor.

Hereditary Spherocytosis defective binding of the RBC cytoskeleton to the plamsa membrane due to mutations involving ankyrin, band 3 or spectrin elevation in mean corpuscular hemoglobin concentration

What would you expect to see in the CSF of patients who have substance use disorders, psychosis and mood disorders? And Parkinson?

Homovanillic acid this is a primary dopamine metabolite

Patient with a serpiginous, puritic rash after walking barefoot on a beach.

Hookworm infection egg containing feces are deposited in shardy soid -- hatch and come into direct contact with human skin dermal penetration usually has a pruritic, maculopapular lesion ant the site of entry. spread of larvae through the adjacent dermal tissue can lead to the formation of migrating, reddish brown serpiginous tracks cat and dog hookworms cannot penetrate the cutaneous basement membrane or spread

Patient with cognitive decline, chorea, and family history of similar symptoms. What is diagnosis and path?

Hungtingtons disease AD, excessive number of trinucleotide repeats in huntingtin gene -- gain of function mutation that results in the toxic accumulation of mutant huntingtin. abnormal protein buildup causes loss of inhibitory GABA neurons in the caudate nucleus. atrophy of the caudate nuclei

Patient with a 4 month history of nonproductive cough and exertional dyspnea. BAL with more than 50% of cells being lymphocytes.

Hypersensitivity Pneumonitis - exaggerated immunologic response to an inhaled antigen (farmers lung due to moldy hay) and birdkeepers (bird facier's lung due to exposure to avian proteins) chronic disease can show diffuse reticular interstial opacities

Causes of acute pancreatitis include:

I Get Smashed idiopathic gallstones ethanol trauma steroids mumps autoimmune disea scorpion sting hypercalcemia/hypertryglyceridemia ERCP drugs (sulf, NRTI, protease inhibitors)

What cytokine is anti-inflammatory

IL-10

What are the anti-inflammatory cytokines and who releases them?

IL-10, IL-4, TGF-beta TH2 and Treg cells secrete them overproduction of proinflammatory cytokines leads to pathology that is observed in inflammatory bowel disease

Which cytokines are more important in allergic conditions?

IL-5 and IL-4

What cellular processes are couple to phospholipase C?

IP3 and DAG cleavage

Patient with acute pruritis following administration of morphine likely has what reaction.

IgE-independent mast cell activation due to opioids, radiocontrast agents, and some antibiotics (vancomycin) occurs due to activation of PKA and PI3 IgE mediated degranulation is more likely to occur due to environmental exposures - foods or stings, and with beta lactams and sulfonamide antibiotics

What type of antigens are given in Rhesus immunization?

IgG anti D antibodies these can cross the placenta but they do not cause significant transplacental fetal hemolysis because the amount of antibody administered is negligible with the amount produced in a normal reaction

What is the pathogenesis of T2DM?

Islet amyloid polypeptide is one factor that is thought to be responsible for beta cell dysfunction. Amylin is store in insulin secretory granules and is co-secreted with insulin from pancreatic beta cells

Patient with delayed puberty plus anosmia. What is the dx?

Kallman syndrome failure of GnRH secreting neurons to migrate from their origin in the olfactory placode to normal anatomical location in the hypothalmus KAL-1 gene or fibroblast growth factor receptor-1 gene decreased LH, FSH, GnRH and testosterone in females have amenorrhea

Patient with multiple respiratory infections and dextrocardia on PE (point of maximal impulse in the right 5th intercostal space).

Kartagener Syndrome primary ciliary dyskinesia AR condition

What causes the massive inflammatory response in neisseria meningitidius infections?

LOS - endotoxins that is released into the plasma via shedding of the outer membrane due to blebbing or bacterial lysis endotoxins bind to toll -like receptor 4 on monocytic and dendtiric cells to release IL-1, IL-6 and TNF-alpha

Patient is given nitrates. What happens to LVEDV, peripheral venous capacitance, SVR?

LVEDV decreases, peripheral venous capacitance increases, systemic vascular resistance decreases (MILDLY but don't forget)

Patient with recent onset of high fever, confusion, headache and watery diarrhea and cough. Numerous neutrophils but no bacteria on gram stain. What is the dx?

Legionnaires disease - high fever with diarrhea, confusion and cough in an older adult who smokes

Turner Syndrome Findings

Loss of paternal chromosome X cystic hygroma and bilateral swelling that is consistent with lymphadema coarctation of the aorta presents with diminished femoral pulses

Patient with initial painless, small, shallow genital ulcer and infection cell. Weeks later develop painful, coalescing inguinal nodes. Cell scrapings show cytoplasmic inclusion bodies. What is the dx?

Lymphogranuloma venereum will contain areas of mixed granulomatous and neutrophic inflammation with intracytoplasmic chlamydial inclusion bodies

Which syndrome should you associate with a thyroid nodule and arm span >height and mucosal neuromas?

MEN 2B * medullary thyroid cancer * pheochromocytoma *mucosal neuromas/marfanoid habitus therefore would expect to see headaches

What cell surface proteins do APCs have?

MHC Class II molecules this is because after phagocytosis or endocytosis -- the protein is degraded in acidified lysosomes and loaded on MHC II

Multiple Myeloma dx

MM is due to light chain cast nephropathy in the kidney -- far exceed the resportive capacity -- form obstructive casts (by combining with Tamm-Horsfall proteins) to cause tubular rupture and kidney injury Note: for the large immunoglobulins to pass through, then would need to cause damage that allows albumin to be detected on dipstick

Child with a peritonsilar abscess who recieves local/topical anesthetics to drain becomes hypoxic.

Methemoglobinemia due to benzocaine which causes Fe2+ to go to Fe3+. unable to bind oxygen and the oxygen binding is increased (causes a left shift). cyanosis that does not improve with supplemental O2. pulse oximetry will be inaccurate --> reads near 85% due to the absorption wavelength

MELAS

Mitochondrial Encephalopathy, Lactic Acidosis, and Stroke-like episodes mitochondrial deficiency

Patient with hx of lung transplant on immunosuppression.

Most likely CMV will see CMV penumonitis - most common form of tissue invasion CMV following lung transplant) and this will show enlarged cells with intranuclear and intracytoplasmic inclusions (viral partical) often with a surrounding halo (owels eye)

Patient with bone pain, fatigue, anemia and hypercalcemia. What is dx? What is tx?

Multiple myeloma increased protein production of plasma cells --> makes them susceptibel to the effects of proteosome inhibitors (bortexomib) a bornoic acid containing dipeptide proteasomes -- recylcing centers for proteins, breakdown misfolded, damaged and cytotoxic proteins into their component building blocks for reuse in new proteins --> results in the accumulation of toxic intracellular proteins - regulates the balance of pro and antiapoptotic proteins (inhibition leads to excess of proapoptotic proteins -- induce apoptosis of the malignant cells)

Patient undergoes coronary revacularization with LVEF at 35%, then 10% recovers to 50%. What is the cause?

Myocardial hibernation chronic myocardial ischemia in which both myocardial metabolism and function are reduced to match a concomitant reduction in coronary blood flow. This prevents myocardial necrosis. coronary revascularization and subsequent restoration of blood flow to hibernating myocardium improves contractility and LV function

Theophylline overdose

N/V, abdominal pain, diarrhea, cardiac arrythmias, and seizures tx: activated charcoal to reduce GI absoprtion beta blockers to help with tachyarrhythmias and benzos or barbituates for seizures

Patient with degredation of IkB inhibitor protein which normally binds to latent transcription factor found in the cytoplasm. What factor is released due to this?

NF-kappa B

Patient with an acute kidney injury after taking ibuprofen. What was the cause?

NSAID induced kidney injury prostaglandins help to maintain renal perfusion by dilating the afferent arteriole (esp when intravascular volume depletion or CKD). Increased prostaglandin synthesis is neccessary to preserve renal blood flow and maintain GFR. inhibition of afferent dilation with NSAIDs results in reduced glomerular filtration and prerenal azotemia with elevated BUN and creatinine urinalysis will be bland.

Patient with excessive daytime sleepiness, episodic loss of motor tone triggered by emotion(cataplexy) and inability to move on awakening (sleep paralysis) suggests what? What would you see on CSF?

Narcolepsy hypocretin-1 (orexin A) and hypocretin-1 (orexin B)

Patient with nystagums, ataxia, poor recollection of the previous nights evens, and high BP and pulse. What is the acute drug toxication?

PCP will have horizontal or vertical nystagmus

Pembrolizumab MOA and use

PD-1 monoclonal antibody -- restores the cytotoxic T cells response and promote tumor cell apoptosis melanoma and RCC

Patient with cyanosis and clubbing to the feet with normal peripheral pulses. Right blood gas is 99%.

PDA left to right shunt that can lead to increased pulmonary vascular resistance and reverse the shunt from left to right differential clubbing and cyanosis in the lower extremities when there is a significant decrease between pre-ductal and postductal oxygen saturation. upper extremities are supplied by oxygenated blood from the left ventricle but deoxygenated blood flows right to left acrsoss the shunt and supplies the descending aorta

What medications can affect the peripheral conversion of T4 to T3

PTU, glucocorticoids, nonselective beta blockers

How does Chancroid present? Cause?

Painful singular ulcer, with tender lymphadenopathy base may have a gray to yellow exudate Cause - haemophilus ducreyi

Patient with a smoking history, upper limb/pain weakness and ipsilateral ptosis and miosis.

Pancoast Tumor - usually non-small cell lung cancers that arise near the superior sulcus local spread makes it so that it goes into the brachial plexus and cause shoulder finsings

What factors is expressed by staph that is more likely to cause a skin abscess?

Panton-Valentine Leukocidin

Patient with hemolytic anemia, hypercoagulability (hepatic vein thrombosis) and pancytopenia with CD55 and CD59 deficiency?

Paroxysmal nocturnal hemoglobinuria mutation in the PIGA gene (aquired) - glycosylphosphatidylinositol anchor (GPI anchor). These are important for keeping complement for attacking the RBCs attack occurs at night due to decrease in the pH and activation of complement activity then

Patient with pins and needles sensation in his legs. painful lesions on his lips and the corners of his mouth. Also with glossitis and angular stomatitis.

Patient has riboflavin deciency this is used as a cofactor in redox reactions

What is NADPH used for in biochemical reactions?

Pentose phosphate shunt is really active in cells experiencing high oxidative stress - where NADPH is used to regenerate reduced glutathione and maintain cell integrity liver and adrenal cortex are involved in reductive biosynthesis (synthesis of fatty acids, cholesterol, steroids) and cytochrome P450 metabolism Phagocytic cells generate a respiratory burst using NADPH

Paranoid Personality Disorder

Pervasive pattern of distrust & suspiciousness beginning in early adulthood & occurring in a variety of settings (no clear delusions) - believes being exploited & decieved by others, interprets benign comments and events as threats, reacts angrily, bears grudges, questions loyalty

Patient with decreased metabolites of a drug. What would that happen?

Polymorphism of cytochrome P450 enzyme cytochrome P450 are responsible for the majority of drug metabolism in the liver - deactivate drugs and facilitate excretion by improving water solubility but polymorphysims can make different phenotypes this can happen with tamoxifene -- decreased levels of the active metabolite

Where is the locus ceruleus located?

Posterior rostral pons near the lateral floor of the 4th ventricle pigmented neurons this is where NE is synthesized, normally leads to arousal and autonomic function (ie BP control)

What is it called when m. tuberculosis is in the back?

Pott Disease - hematogeneous seeding from the primary infection radiographic evidence of vertebral bone destruction and a fluid collection can develop months or years later

Patient with scaly, erythematous plaques on the extensor surface. What is dx and histology?

Psoriasis - most common in areas exposed to pressure or friction -- extensor surfaces of the elbows tha knees Koebner phenomenon - minor trauma can precipitate formation of lesions Disruption of the epithelial barrier leads to activation of antigen presenting dendritic cells and subsequently to a self-reinforcing inflammatory cascade that is characterized by recruitment and activation of T helper cells and proliferation of keratinocytes hyperkeratosis (thickening of the stratum corneum) parakeratosis (retention of nuclei in the stratum corneum) epidermal hyperplasia (acanthosis) - elongated and clubbed rete ridges corresponding to typical erythematous plaques perivascular lymphocytes and dilated dermal capillaries

The region where the frontal, parietal, temporal, and sphenoid join together? What artery supplies here

Pterion this is where the middle meningeal artery gets damaged to cause an epidermal hematoma. the middle meningeal artery is a branch of the maxillary artery (this enters the skull at the foramen spinosum and supplies the dura mater and periosteum)

Patient with Raynauds and CREST syndrome. Now with loud pulmonic component of S2 and progressive dyspnea - what is the most likely cause?

Pulmonary arterial HTN due to secretion of T cells and TGF-beta --> stimulates firboblasts to increase the production of collagen and extracellular matrix proteins results in vasoconstriction and smooth muscle proliferation with intimal thickening of the vascular smooth muscle wall

Osteosarcoma tumorgenesis

RB1 tumor supressor gene -- encodes for RB - which is a protein that regulates cell-cycle progression. TP52 - tumor suppressor gene

Patient in cardiogenic shock after an inferior wall MI. Lungs are clear. What will CO, PCWP, CVP be?

RCA also gives marginal branches that supply the RV --> RV infarct. see hypotension, distended jugular veins and clear lungs. decreases RV stroke volume --> decreased LV filling and CO. with less LV filling, PCWP also decreases. Elevated CVP due to impaired forward flow and backup of blood into the systemic venous system

Patient with progressive agitation, disorientation and pharyngospasm after a camping trip.

Rabies contaminated saliva from and infected animal -- bullet shaped envelope with knob-like glycoproteins that allow it to attach to the nicotinic acetylcholine receptor at the neuromuscluar juction

Ghon complexes become what?

Ranke complex -- these sites become calcified and fibrosed and then can be visualized on gross pathology and radiographic imaging

What does RAS do?

Ras increases the renal blood flow and the tubular hydrostatic pressure in an attempt to maintain the GFR (overal in a hypovolemic patient these are still decreased).

What are the metabolic effects of metformin?

Reduced hepatic gluconeogenesis -- inhibits glycerophosphate dehydrogenase and complex I to reduce the availability of substrates for gluconeogenesis increased insulin dependent peripheral glucose uptake reduces circulating lipid levels -- upregulates AMP-activate protein kinase in hepatocytes and inhibits lipogenesis

Patient with DKA now given subq. What were they transitioned to?

Regular insulin starts working in 30 mins, peaks in 2-4 hours and lasts 5-8 hours

Patient with mid-esophageal and mediastinal lymphadenopathy with history of smoking and alcohol. Lesion is in the middle third of the esophagus?

SCC carcinoma - sheets of pleomorphic squamous cells and adundant eosinophilic cytoplasm with large, bizarre nuclei and atypical mitosis. keratin formation and intercellular bridges.

What two antidepressant classes can cause sexual side effects?

SSRI and SNRI

How do you calculate ejection fraction?

SV/EDV x100

50 yo patient with cough, shortness of breath, and fatigue. Characteristic granulomas.

Sarcoidosis elevated calcium levels due to increased acitvation of 1 alpha hydroxylase mediated vitamin D activation in macrophages

Patient with skin rash involving hands, feet and scalp. Hx of HIV and has erythematous patches with scales and crusting. Organisms seen in the stratum corneum on bx.

Scabies. Sarcoptes scabiei impaired cell mediated immunity cannot contain the infection and develop crusted scapies tx. with topical permethian or oral ivermectin

Patient with generalized rash, lymphadenopathy and a corkscrew shaped organism on histopathology. What is the disease? How would you treat it?

Secondary syphilis caused by Treponema pallidum. dark field microscopy and specialized stains can identify the spirochete. tz: with penicillin - beta lactam antiboitic that disrupts the cell wall by inhibiting transpeptidase which cross links the cell wall. must us IM for prolonged exposure because this antibiotic only works when the organism is replicating.

Patient with chronic dry mouth and palpable salivary gland enlargement and extensive lymphocytic infiltrate with a germinal center on salivary gland biopsy.

Sjogren syndrome corneal ulcerations and dental caries chronic B lymphocyte stimulation in SS predispose patients to malignant transformation causing non-hodgkin lymphoma (marginal zone lymphoma, diffuse large B cell lymphoma)

Patient with Graves disease and hyperthryroidism. How does the medication help with graves ophthalmopathy?

TSH receptors on fibroblasts, adipocytes and other cell types are activated --> excess deposition of extracellular glycosaminoglycans and T cell activation and inflammatory infiltration glucocorticoids decrease peripheral conversion of T4 to T2, but their antinflammatory effects improve graves opthalmopathy

What is in a telomere?

TTAGGG repeats

Patient with HIV recently started on antiretrovirals now with proximal tubule dysfunction (hypophosphotemia, glucosuria, proteinuria, bx abnormalities. What is the likely cuase

Tenofovir-induced nephrotoxicity primarily eliminated in the proximal tubule of the cells of the kidney -- can interfere with mitochondrial DNA synthesis and result in cell damage. will manifest as acute kidney injury - elevated creatinine and water retention or with signs of proximal tubule dysfunction. histo will show damage to proximal tubule cells and evidence of giant mitochondria (large eosinophilic inclusions) Trimethoprim-sufamethoxazole does not cause focal damage to the proximal tubules

Accumulation effect in epi means what?

The reduction in risk is associated with the duration of exposure the exposure must be around for some minimal set of time before it is affected

How to integrins bind to the extracellular matrix?

They use fibronectin

Patient with recurrent episodes of chest pain, tachycardia, shortness of breath, sweating and tremulousness in a young, otherwise healthy patient with normal EEG.

This a panic disorder somatic presentation are common. administration of BZO for the rapid relief of symptoms and SSRI and SNRI for ongoing treatment

2 day old with abdominal distension, bilious emesis and x-ray findings with bowel obstruction. Green inspissated mass (dehydration meconium) in the distal ileum makes you think of meconium illus. What is he most at risk for?

This is a specific finding for CF at risk for pnuemoniae

What does the Ghon complex do?

This is an area of infection - lower lobe and the ipsilateral hilar lymph node - that together are infected by mycobacterium tuberculosis typically is a calcified right hilar lymph node

What does mucin expression in a tumor typically mean?

This means that there is a poor prognosis typically, provides a protective barrier to epithelial cells

Patient presents after dissection of the posterior triangle of the neck and with left shoulder drooping and inability to abduct past 100 degrees.

Trapezius muscle is injured due to injury of the spinal accessory. symptoms: drooping of the shoulder, impaired abduction of the arm above 100 degrees and lateral displacement of the scapula deltoid only lifts to 100, trapezius >90 and serratus anterior lifts >100

Patient with subacute meningeal symtpoms and thick gelatinous exudate on autoposy. HIV patient.

Tuberculous Meningitis - thick gelatinous exudate most prominent in the basal portion of the brain. encase CN and lead to CN palsy to invade the circle of Willis Tuberculous vasculitis of cerebreal arteries -- multiple bilateral brain infarctions (esp. periventricular) Hydrocephalus due to obstruction of tubercular proteins -- elevated intracranial pressure and ventriculomegaly

Patient with tenderness and easy bleeding of the gums when she brushes her teeth. She eats a tea and toast diet. What is she deficient in and where is this made in the cell?

Vitamin C deficiency - scurvy gingival swelling/bleeding, petechiae, ecchymoses and poor wound healing. perifollicular hemorrhages and coiled (corkscrew) hairs are also commonly seen. collagen synthesis and proline and lysine hydroxylation occurs in the RER

Patient with well defined, variable sized patches of depigmentation after exposure in sun. What is dx and path?

Vitiligo would show an absense of melanocytes and melanin pigment due to autoimmune acitivity, neurohormonal toxicity specific for melanocytes and melanocytic self-destruction. associated with other autoimmune disorders

What would you need to do to make the minute ventilation match the alveolar ventilation?

Would need to decrease the physiologic dead space minute ventilation is the amount of air a person breathes in a minute while the alveolar ventilation is the amount of air volume that reaches the alveoli per minute

arsenic posioning presentation

abdominal pain, vomiting, severe watery diarrhea, delerium and hypotension garlic odor on breath tx: dimercaprol

What reaction occurs in ketone synthesis?

acetoacetyl-CoA to 3-hydroxy-3-methylglutary-CoA this occurs in starvation situations but does not make glucose

Organophosphates

acetylcholinesterase inhibitors DUMBELS diarrhea/ diaphoresis, urination, miosis, bronchospasm, emesis, lacrimation, salivation Atropine > pralidoxime

Patient with a transient loss of consciousness due to decreased cerebral perfusion. What is the most likely cause

acetylcholinesterases (donepezil, rivastigmine) used in the management of Alzheimer dementia causes enhanced parasympathetic tone that can lead to bradycardia and AV block in some patients --> reduced cardio output that is seen as presychopy

Patient with rosette like accumulation of basophilic filamentous bacteria in the setting of poor dentition. presents with lower lobe consilation and bronchograms.

actinomyces -- presents with sufur granules (under H/E they have an amorphous, basophilic appearance) tx: PCN

Patient with fever, RUQ pain, jaundice, confusion and hypotension.

acute cholangitis due to biliary obstruction -- enables bacteria to proliferate within the biliary tree - usually due to calculous obstruction of the common bile duct

Babesiosis Presentation

acute febrile illness, thrombocytopenia, hemolytic anemia (indirect hyperbillirubinemai, elevated LDH, low haptoglobin), abnormal LFTs, and intraerthrocytic inclusions (ring shaped, maltese cross)

Patient who gets a blood transfusion and then prevents with fever and chills, hypotension, dyspnea, chest and back pain and hemoglobinuria.

acute hemolytic transfusion reaction minutes to hours due to ABO incompatibility antibody mediated T2HS -- activates compleement mediated cells lysis using IgG and IgM

Patient with transplant and is asymptomatic?

acute rejection usually within the first 6 months usually aymptomatic and discovered on survelliance bx histo: perivascular and interstitial mononuclear infiltrates

Patient with guillain barre syndrome. What are the pathological findings?

acute, immune-mediated demylinating polyneuropathy due to molecular mimicry where infectious agents provoke and immune response that cross reacts with the meylin histo will show and inflammatory infiltrate located in the endoneurium - the innermost layer of connective tissue that surrounds a nerve axon and its corresponding blood vessel -- leads to lipid laden macrophages due to stripping of the myelin sheath from the axon

Patient presenting with a retroperitoneal hematoma near the psoas muscle

acute, severe pain in the groin, lower abdomen or back and can cause injury to the femoral nerve femoral nerve descends through the psoas major muscle, emerges laterally between the psoas and iliacus quadricpes wekaness, decreased patellar reflex, sensory loss over the anterior and medial thigh and medial leg

Acyclovir mechanism of action?

acyclovir is a guanosine analog --> phosphorylated to acyclovir monophosphate by virally encoded thymide kinase (this is the rate limited step in acyclovir activation) then is is phophorylated by cellular anzymes into the active triphosphate form -- impairs viral DNA polymerase-mediated replication of HSV EBV and CMV do not have the thymidilate kinase so they cannot do this

Patient with abdominal pain, weight loss, salt craving, orthostaisis and electrolyte disturbance.

addisons disease autoimmune destruction of bilateral adrenal cortex. reduction in circulating mineralcorticoids, glucoroticoids and androgens.

Patient on long term glucocorticoids. What can be expected?

adipose: lipolysis, altered fat distribution adrenal cortex: atrophy bone: osteoporosis immune system: suppression, T cell apoptosis Liver: increase gluconeogenesis and glycogenesis skeletal muscle: atrophy skin: tinning, stria, impaired wound healing

Child with hematogenous osteomyelitis. where is it located?

affects the metaphysis of long bones - region contains slow-flowing, sinusoidal vasculature that is conducive to microbial passage. adults are less likely to develop hematogenous osteomyelitis in the long bones but if they do it is in the epiphysis.

How do opiates work?

afferent neuron - close voltage gated calcium channels, reduce calcium influx, and decrease excitatory neurotransmitter release from the presynaptic terminal. On the postsynaptic membrane -- open potassium channels leading to mambran hyperpolarization from potassium efflux.

Patient with connective tissue hyperpigmentation and degenerative joint disease. Accumulate homogentisic acid.

alkaptonuria AR deficiency of homogentisic acid oxidase cannot break down tyrosine

What do the poisons in mushrooms do?

amatoxins - death cap transported to the liver by portal circulation where active transport by organic anion transporting polypeptide and sodium taurocholate co-transporter concentrates the toxin within liver cells. Amatoxins bing to DNA dependent RNA polymerase type II and halt mRNA synthesis --> apoptosis usually rapid cell turnover locations -- GI tract and PCT alpha-amanitin can confirm dx through urine test

How does amino acid attachment happen?

aminoacyl tRNA synthetases catalyze this reaction these are highly specific and some synthetases can proofread their specific tRNA molecules and hydrolyze the amino acid bond when incorrectly charge erroneous amino acid/tRNA coupling by AA tRNA synthetase causes the wrong amino acid to be incorporated into the polypeptide chain

What antibiotic causes oto and nephrotoxicity?

aminoglycosides bind to the bacterial 30s subunit -- genetic code misreading and bacterial protein synthesis inhibition - impact translocation in tRNA

Aniscoria pathology

aniscoria = pupillary asymmetry - means there must be a unilateral defect with input from the ocular sympathetic or parasympathetic pathway. asymmetry increases in dim light - smaller pupil is unable to dilate due to loss of sympathetic never input. asymmetry increases under bright light - larger pupil cannot constrict due to loss of parasympathetic input

CREST syndrome antibodies?

anticentromere

What is the antibody associated with autoimmune hepatitis?

antismooth muscle antibody presents as chronic progressive hepatitis in a middle aged women

What are the central effects of dopamine replacement in Parkinsons?

anxiety and agitation these will not be reduced with carbidopa and they can increased

What murmur is best heard with the patient leaning forward?

aortic regurgitation -- characteristic decrescendo diastolic murmur that has peak intensity just after the aortic valve closes when there is a maximal pressure gradient decrescendo mumur because the pressure gradiate falls as the blood regurgitates into the left ventricle

What does Candida look like under the microscope?

appears as budding yeasts with pseudohyphae, but then can form true hyphae from the yeast and this is a germ tube

Germ cell tumors in the brain

arise from the pineal gland in the dorsal midbrain. These cause obstructive hydrocephalus with symptoms of increased intracranial pressure (HA, vomiting, AMS) and Parinaud syndrome (upward gaze palsy)

In Hirschsprung disease, what is usually involved?

arrest of migration of neural crest cells into the colon. always involves the rectum and anus, sometimes sigmoid colon because the neural crest cells migrate caudally, the rectum is always involved

common femoral artery anatomy

arterial puncture above the inguinal ligament will increase the risk of retroperitoneal hemorrhage

Treat malaria in areas with resistance using what drugs?

atovaquone-proguanil or artemisinins. if there is sensitivity can use chloroquine. need to use primiquine only when there is a dormant hepatic phase. p falciparum does not have a dormant phase.

Patient with a left atrial mass on echo. What is the cause? What is the path?

atrial myxoma left atrium -- systemic embolization can occur release IL-6 -- cause constitutional symptoms may mimic a mitral valve stenosis path: amoprhous extracellular matrix with abundant mucopolysaccharide - may see areas of necrosis due to high vascularity

What parts of the HPA axis are affected by long term cortisol use

atropjy of the CRH releasing neurons in the hypothalmus, pituitary cortcotropic cells, and the adrenal zona reticularis (androgen) and zona fasciculata (cortisol)

How can the grade of mitral valve regurgitation be determined?

audible S3 gallop - when the left venticle is unable to accommodate the excess blood flow. - due to the sudden cessation of blood flow into the left ventricle during passive filling - due to higher volume of blood flow or more dilated left ventricle.

Bullous Pemphigoid

autoimmune condition with serous fluid-filled tense bullae on normal or erythematous skin. hemidesmosomes on the basement membrane of the dermal-epidermal junction destructive inflammatory cascuase - entire epidermis separates from the dermis -- subepidermal, nonacntholytic blisters IgG or C3 deposits in a linear pattern along the basement membrane

What medications should you avoid in HOCM? What should you use?

avoid vasodilators (dihydropyridine calcium channel blockers, nitroglycerin, ACE inhibitors) -- decrease systemic vascular resistance, leads to decreased afterload and lower LV volumes Diuretics - decrease LV venous filling (preload) and result in greater outflow obstruction can use negative ionotropic agens - beta blockers, nindihydropyridine calcium channel blockers and posopyramide to reduce LVOT obstruction

What is the process of Wallerian degeneration?

axon is damanged and there is breakdown of the myelin sheath distal to the site of injury CNS - phagocytic macrophages/microglia are recruited more slowly d/t blood brain barrier. oligodendrocytes also become inactive and undergo apoptosis. slows removal of the myelin debris which can perist for year in the degenerating tracts and suppress axonal growth via myelin factors. Astrocytes form a glial scar that serves as a barrier.

Patient with a Beta-lactamase producing bacteroids species. What should be treatment?

bacteroides - gram negative anaerobic rods that produce B lactamase. combination of piperacillin and taxobactam is affective against gram positive, gram negativ and anaerboic bacteria also metronidazole, carbapenums, and clindamycin

Rules for disclosure of information when the patient is incapacitated?

basic information can be shared, if in the professional judgement, doing so would be in the patients best interest

What is condyloma acuminatum?

benign warty growth on genital skin due to HPV type 6 or 11 characterized by koliocytic change

In short term therapy of specific phobias, what could you consider using?

benzos - these should not be used long term

4 week old baby with elevated direct bilirubin and dark yellow urine but few pale colored stools. also has enlarged, firm liver.

biliary atresia - progressive complete or partial obstruction of extrahepatic bile ducts normal at birth and then undergoes immune or viral induced destruction jaudice with dark urine (excessive bilirubin excretion) and pale stools (lack of intestinal bile) inflammation --> firm hepatomegaly

Patient with a CCK stimulation test that shows slow and incomplete gallbladder emptying with symptoms. What is the pathologic finding?

biliary sludge - cholesterol monohydrate crystals, calcium bilirubinate, and mucus) not likely to be a pigmented stone (these are brown -- biliary tract infection with microbes producing B glucuronidases-- or black -- chronic hemolytic anemias (sickle cell disease)

Mechanism of action of penicillin?

binding to and inhibiting transpeptidase - this enzyme catalyzes the final cross-linking step in the peptidoglycan cell wall formation connecting it to the D-alanine-D alanine of another petidoglycan molecule

How does vacomycin lead to cell wall distruction?

binds to the terminal D-alanine residues of cell wall glycoproteins and prevents transpeptidases from forming cross-links

Zidovudine MOA and SE

bone marrow toxitiy NRTI

What is similar between babesiosis and lyme disease?

both transmitted by the Ixodes tick -- coinfection is common

If you damage the median nerve, what artery runs alongside it?

brachial artery

Length of time for diagnosis of schizophrenia disorders?

brief psychotic disorder: >1 psychotic symptoms lasting >1day and <1 month schizophreniform: >1 month but less than 6 months schizophrenia if more than 6 months

Which drug class can you use in depression that does not cause sexual side effects?

buproprion NE and Dopamine reuptake inhibitor -- stimulating effects contraindicated in bulimia, anorexia and seizure because lowers the seizure threshold

How does myocyte relaxation occur in the heart?

calcium efflux from the cytoplasm. intracellular calcium is removed primarily via an Na/Ca exchange pump and sarcoplasmic reticulum Ca-ATPase pump (SERCA) NCX - uses the large Na gradient to pump Ca out of the cell (one Ca for 3 Na) SERCA is a Ca ATPase pump that actively transfers Ca from the cytosol to the lumen of the SR at the expense of ATP hydrolysis

What is usually injured in prostate removal?

can causes erectile dysfunction prostatic plexus -- originates from the inferior hypogastric plexus (from the pelvic and sacral splanchnic nerve) lesser and greater cavernous nerves arise form the prostatic plexus -- involved in penile erection

What is a side effect of glucocorticoids?

can develop early cataracts generally cataracts are due to chronic photoxidative injury -- this could be a side effect of glucocortiocid induced transcription of genes in the lens epithelium

Patient with hypotension, tachycardia and jugular venous distension with clear lung and pulsus paradoxus.

cardiac tamponade pulsus paradoxus -- abnormal exaggerated decrease in systolic blood pressure >10 mmHg on inspiration

How is compression of the ulnar nerve in the carpel tunnel different than in the pronator teres?

carpal tunnel -- impaires sensation to the palmar aspects of the first 3 1/2 digits pronator teres - sensation is impaired not only to the palmar aspect of the first 3 1/2 digits but also the entire lateral palm and thenar eminence (palmar branch)

Rhabdomyolysis acute kidney injury

causes ATN because of myoglobin degenerationi and heme pigment release --> acute tubular necrosis through direct cytotoxicity and renal vasoconstrition microscopy: granular, muddy brown casts note: myoglobin will cross-react with urine dipstick that detect hemoglobin -- false positive result but really no RBCs

What happens with a lunate dislocation?

causes compression of the carpal tunnel and will compress the median nerve causes: 1) numbness pain and paresthesia in the palmar surface of the first 3 and 1/2 digits -- weakness of the first and second lumbrical muscles 2) recurrent branch of the median nerve to the thenar muscles -- wekness of abductor pollicis brevis (thumb aduction), fexor pillicis brevis (thumb flexion) and opponens pollicis (thumb opposition)

Sickle cell disease presentation

causes intra and extravascular hemolysis --> increased indirect bilirubin and LDH and decreases haptoglobin haptoglobin binds circulatin hemoglobin to reduce renal excretion of free hemoglobin and prevent tubular injury

What is a risk associated with hydroxychlorowuine?

causes retinopathy --> decreased central visual acuity, photopsia, and central macular degeneration

Difference between physiologic and cerebellar tremor?

cerbellar - action tremor -- low frequencey and high amplitude -- increase in amplitude as an action approaches the target frequently will see other signs too physiologic - action and rest, usually low amplitude and high frequence - not visible under normal circumastances and is enhanced with sympathetic activation

How would penicillins and cephalosporins develop resistance?

change in protein structure to prevent the binding of these proteins

Why do older patients have a harder time responding to EPO?

changes in cellular composition of the bone marrow impaires the generation of new cells in response to acute stress older patients have a higher quanity of fat and a reduced overall mass older patients do not have an increase in bone marrow fibrosis, just a decrease in bone marrow mass

Female with gallstones and taking a fibrate. What enzyme activity is decreased that causes this?

cholesterol 7 alpha hydroxylase this enzyme catalyzes the rate limiting step in the synthesis of bile acids -- reduced bile acid production results in decreased cholesterol solubility in bile and favors the formation of cholesterol gallstones

What disease processes are charactertized by prolonged pruritis and fatigue, clay colored stools and osteoporosis?

chronic cholestatic processes - PBC, PSC will have these due to reduce intestinal bile flow and vitamin D deficiency

Bronchiolitis obliterans

chronic lung transplant rejection submucosal lyphocytic inflammation in the walls of small airways slowly worsening dyspnea, dry cough is the initial presentation

Patient with cough, dyspnea, obstructive findings on spirometry and firbrotic destruction of the small airways?

chronic transplant rejection airflow limitation with a drop in FEV1 and FEV1/FVC ratio bronchiolitis obliterans --

What is the last cell type to disappear as move down the respiratory tree?

cilliated cells are present in the proximal portions of the respiratory bronchioles, but are not present in the ducts This is important because cilia function to propel mucus toward the pharynx so they must be the last to disappear

Which class of antiarrythmics have the lowest bidning state? middle? high?

class IB - lidocaine - has the weakest binding compared to other class I antiarrythmics class IC - propafenone, flecainide - have the strongest binding (slowest to dissociate from the channel) and this allows their blocking effects to accumulate over multiple cardiac cycles Class IA- disopyramide, quinidine, and procainamide - class IA antiarrythmics drugs that have intermediate dissociate speed

What proteins are upregulated to cause tight junction formation?

claudins, occludin

Systemic Mastocytosis

clonal mast cell proliferation in the bone marrow, skin and other organs associated with mutation in KIT receptor tyrosine kinase with prominent expression of mast cell tryptase excessive histamine release from degranulation of mast cells mediates many of the symptoms of the disease - syncope, flushing, hypotension, pruritus and uticaria histamine also induces gastric acid secretion --> gastric ulceration excess acid inactivates pancreatic and intestinal enzymes, causing diarrhea

Patient with abdominal pain, diarrhea and leukoctyosis. on sigmoidoscopy see white-yellow plaques composed of fibrin, inflammatory cells and cellular debris.

clostridium dificile and patient likely had PNA and was given antibiotics bacterial PNA fiven fluoroquinolones increases the risk of C dif

Patient died due to intracranial hemorrhage from a ruptured cerebral aneurysm. Found to have a cardiac defect, what was it?

coarctation of the aorta decreased perfusion to the lower extremities and asymptomatic upper extremity hypertension in children and adults complications: 1. cerebral aneurysm with life threatening rupture that causes subarachnoid hemorrhage.

Patient with Clostridium Septicum causing spontaneous gas gangrene. What is his risk factor?

colonic malignancy -- allows for a portal of entry. spore forming, exotoxin producing gram positive bacterium that is commensal in the GI tract. causes subsequent hematogenous dissmination and spontaneous gas gangrene when GI mucosa is broken down

What similar precursor molecule is ACTH, MSH, and B-endorphin all from?

come from POMC

What does the musculocutaneous nerve do?

comes from C5-C7 and the lateral cord innervates the major forearm flexors (biceps brachii and brachialis and coracobrachialis lateral cutaneous nerve to provide sensory to the lateral forearm

Salicylate toxicity

comes from aspirin tinnitis, N/V, alteration in mental status primary respiratory alkalosis with a primary anion gap metabolic acidosis tx; with sodium bicarb in the blood

Patient with RCC. What is the pathology?

common in history of chemical exposure and necrotic kidney mass. orriginates in the renal cortex. Smoking, obesity, HTN and toxin exposure (heavy metal, petroleum by products, asbestos) clear cell carcinoma -- epithelium of the proximal renal tubules. phere like mass composed of golden yellow tissue (due to high lipid content) with areas of focal necrosis and hemorrhage) invade renal vein --> IVC

Urethral injury that causes high riding prostate

common in pelvic fracture causes a membranous transection

Patient with a fracture at the neck of the fibula. What nerve is injured. What are the findings?

common peroneal n. loss of dorsal foot sensation as well as impaired dorsiflexion and eversion resulting in foot drop superifical -- lateral compartment of the leg to everrt, sensory to dorsum of foot deep - anterior compartment of the leg - main dorsiflexors of the foot and toes sensory innervation between the first and second digits of the foot

In what conditions would concentric hypertrophy be more likely to occur?

conditions that create ventricular pressure overload -- involves ventricular wall thickening due to addition of myocardial contractile fibrils in parallel

Baby that presents with a palpable bulge in the child's neck, favoring looking to one side and cries when the head is turned the other way. What is the dx and why?

congenital torticollis due to brith trauma or malposition of the head in utero (due to fetal macrosomia or oligohydramnios) which can cause sternocleidomastoid muscle injury and fibrosis. may have hip dysplasia, matatarusus abductus and talipes equinovarus pe: head is tilted toward the affected side with the chin pointed away from the contracture. soft tissue mass may be palpable in the inferior one third of the affected SCM.

What are the teniae coli?

continuous layer of longitudinal smooth muscle that surrounds the rectum just below the serosa these coverage at the root of the vermiform appendix and can be used as a surgical landmark.

Stroke in the temporal lobe causes what visual defect

contralateral upper quandrantanopsia this is due to the lower division of the geniculocalcrine tract to be in the temporal lobe

Recurrent laryngeal nerve path

could be blocked by the enlargement of the left atrium (think d/t mitral stenosis when hear a mid-diastolic ruble best heard at the cardiac apex this is because it loops behind the ligamentum arteriosum and underneath and around the aortic arch up back to the trachea by the larynx Ortner syndrome - mitral stenosis that causes left atrial dilation sufficicent to impinge on the left recurrent laryngeal n.

Patient undergoes radiofrequency ablation form PSVT near the crista terminalis. What is likely injured?

crista terminalis -- located in the right atrium and is the site of origination for atrial PSVT. right phrenic nerve -- courses along the pericardium tht overlies the right atrium and is at risk. will see elevation of the right hemidiaphragm on chest x-ray

Patient with intracellular protozoa with rod-shaped kinetoplasts. What is the dx?

cutaneous leishmaniasis transmitted through the bites of infected sand flies -- matures in mammalian macrophages and are visualized on biopsy as intracellular, round oval amastigoes with rod shaped kinetoplasts. chronic, enlarging, pinkish papules at the site of the bite that develops into a nodules or plaque and ulcerates

Patient with a skin rash - several violaceous, raised, nonblanchable lesions on the bilateral lower extremtities a week after taking oral penicillin therapy.

cutaneous small vessel vasculitis only affects the skin and arises due to drug (penicillins, cepahlosporins, sulfonamides, phenytoid, allopurinaol) markedly inflammed small blood vessels with firbinoid necrosis primarily nuetrophils in the first 24 hours and fragmented neutrophilic nuclei (leukocytoclastic vasculitis) with mononuclear cells in older lesions skin exam shows nonblanching palpable purpura

Aortic Dissection

cystic medial degredation with aging, collagen, elastin and smooth muscle are broken down and replaced -- leads to a basket weave pattern - many cystic colections of mucopolysaccharides a small intimal tear can lead to dissection

Patient with an MI and now dyspnea and orthopnea. What is likely to be seen in the lung?

d/t left ventricular failure which can result in rapid onset of pulmonary venous hypertension and acute pulmonary edema fluid that accumulates is transudate -- an ultrafiltrate of plasma caused by changes in hydrostatic or oncotic pressure engorged capillaries are evident and the intraalveolar transudate appears as acellular pink material

What causes scapular winging?

damage to long thoracic n. -- lymph node disection in radical mastectomy

Young patient with dyspnea, lower extremity edema, jugular venous distension and pulmonary crackles. What is the dx and most likely cause?

decompensated heart failure if there is a symptomatic viral prodrome - fever, sinus congestion, myalgias - dialated cardiomyopathy due to viral myocarditis path: depletion of cardiomyocytes with subsequent fibrosis causes weakened myocardial contracitlity (systolic dysfunction), volume overload and ventircular dilation (eccentric hypertrophy)

Patient is in early septic shock. What will you see in PCWP, CI, SVR, mixed venous O2 saturation?

decreased PCWP, and SVR increased CI and mixed venous O2 saturation note that in late stages may see a decrease in cardiac index. but in the early stages (and with this patient having flusing) more likely that the compensatory increase in sympathetic drive that increases heart rate and mycardial contractility is driving this increase. high blood flow rates then will prevent complete extraction of oxygen by the tissues -- results in high mixed venous oxygen saturation

What changes are normal in an aging hear?

decreased left ventricular chamber size -- especially in the apex to base dimension --> ventricular septum aquires a sigmoid shape with the basilar portion bulging into the left ventricular outflow tract. atrophy of the myocardium results in increased interstitial connective tissue with concomitant extracellular amyloid deposition. lipofuscin pigment - result of indigestible byporducts of subcellular membrane lipid oxidation.

Why does vaccine failure happen with aging?

decreased production of naive B lymphocytes due to immunosensence. There is the same number of memory T lymphocytes - they just tend to be against antigens that have already been seen. There is also no change in antibiotic quality

What predisoposes to calcium stone formation?

decreased urinary citrate and low fluid intake will cause stone formation citrate is normally excreted by the kidneys and binds to ionized calcium in the urine while preventing the formation of insoluble calcium oxalate complexes. When urinary citrate is low (hypocitraturia) increased calciuma availbility leads to the formation of calcium oxalate complexes that cen precipitate and form calcium oxalate stones

What is the normal role of estrogen in the body?

decreases bone resorption

How do the testes descend into the scrotum?

deep inguinal ring - opening in the transcersalis fascia bound laterally by the transcersus abdmonius and medially by the inferior epigastic enters the scrotum via the superficial inguinal ring -- physiologic opening in the external oblique muscle aponeurosis

What is the pathogenesis of wilsons disease?

defective ATP7B results in impaired biliary excretion of copper -- accumulation of hepatocellular copper results in oxidated stress and apoptosis --> with cell death, the free copper is then released into the blood stream and deposited into extrahepatic tissues (basal ganglia, cornea), causing the classic triad of hepatic, neurologic and psychiatric (depression) symptoms. ATP7B is also required for the hepatic production of ceruloplasmin -- inability to create and secrete this results in low levels that can be used for dx

Cumulative incidence calculation

defined as the number of new cases of a disease over a specific period of time divided by the number of people AT RISK at the beginning of the period no time in the denominator

What happens in a clavicular fracture?

deltoid will pull the distal freagment of the clavicle in the inferolateral direction pulss is away from the sternocleidomastoid and trapezius muscles deltoid muscle originates on the distal clavicle and inserts onto the humerous

Schizophrenia symptoms

delusions hallucinations disorganized speech disorganized or catatonic behavior negative symptoms