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Nodular Glomerulosclerosis

*Diabetic Nephropathy* -ovoid or spherical hyaline masses (KW lesions) that's PAS+

Protamine Sulfate

Heparin-specific antidote (binds heparin)

Sequelae of SAH is due to what mechanism?

*Vasospasm* *Vasospasm* occurs in the vessels surrounding the ruptured aneurysm. The mechanism of vasospasm is related to impair brain autoregulation Tx: *CCB* #500

Nasopharyngeal specimen obtained and cultured on a selective medium containing Vancomycin, Colistin, Nystatin, and Trimethoprim. The organism most likely isolated is typically associated w/ what condition?

*Meningitis* The agar described it *Thayer-Martin Medium*, used to isolate *Neisseria sp.* #1024

Nondepolarizing Blockers

*Vecuronium* These are competitive inhibitors of postsynaptic AChRs., decreasing strength of muscle twitch, and showing *progressive reduction in response (fade)*.

Rats exposed to high levels of carbon tetrachloride suffer rapid and extensive liver damage. LM of liver: fatty change and hepatocyte necrosis. These changes are a result of:

*Free Radical Injury* *CCl4* causes free radical injury and is oxidized by P450 system. The free radicals react w/ lipids, resulting in lipid degeneration and H2O2 formation (*lipid peroxidation*) #314

Why is there a slight decrease in Partial Pressure of O2 as blood gas from alveolar capillary bed to systemic arterial blood?

*Mixture of deoxygenated blood* *Bronchial As.* travel w/ the pulmonary A. to provide dual blood supple for the lungs. *Bronchial Vs.* return a small portion of blood to the RA and *pulmonary Vs.*. *Small cardiac veins* also drain into the LA. #1542

24 yo female c/o 2 episodes of bloody emesis and now feels lightheaded and dizzy. Dx w/ Factitious Disorder and she admits to ingesting rat poison several ds ago. PE: scattered ecchymoses. Abdomen soft and nontender. Rectal exam shows maroon-colored, guaiac + stool. Immediate tx w/ what?

*Fresh frozen plasma* *Rodenticides* are known as *"Super Warfarin"* and cause decrease in vitamin k-dependent coagulation factors. *FFP* contains all blood clotting factors and proteins

Rapidly rising pulse w/ high amplitude

*Hyperkinetic pulse* is due to rapid ejection of a large stroke volume against a decrease afterload

56yo male c/o acute, severe chest pain. EKG normal. Chest CT: wide aortic arch w/ fibrous line in the middle of the lumen. What is the most important risk factor for this condition?

*Hypertension* Pt has an *Aortic Dissection*, as seen by the widened aortic arch and the "fiber" being the tunica intimate torn from the wall. #473

A pt w/ T2DM will most likely die from what?

*Myocardial Infarction* Cardiovascular mortality increases 2-4 fold w/ T2DM and about 40% of pts die secondary to coronary heart disease. *Highest risk factors for CHD*: Noncoronary atherosclerotic disease, DM, and CKD. *Major RFs*: HTN, hyperlipidemia, cigarette smoking, increased age, obesity, and physical inactivity #1011

71 yo male w/ c/o progressive exertion dyspnea and sever orthopnea. PE: bilateral lower extremity edema and JVD. Cardiac auscultation at apex shows a low frequency sound right after S2. These osculatory findings most likely reflect what?

*Increased LV EDV* Pt has an *S3 gallop* b/c of *LV volume overflow/failure*. S3 develops b/c of *forceful rapid passive filling* that exceeds capacity of ventricle. #2108

Osler Nodes

*Painful*, violaceous nodules seen on finger tips and toes of those w/ IE; due to *immune complex-mediated vascular lesions* (also Roth Spots)

Urine labs: Inulin 200.0 mg/dL, Glucose 0, K+ 50.0 mEq/L, Uric acid 15.0 mg/dL, and PAH 100 mg/dL. Serum labs: Inulin 2.0 mg/dL, Glucose 90 mg/dL, K+ 5.0 mEq/L, Uric acid 3.0 mg/dL, and PAH 0.2 mg/dL. Assuming Hct of 50% and urine flow rate of 1 mL/min, what is the best estimate of Renal Blood Flow?

*1,000 mL/min* *RBF = RPF/1-Hct* *RPF = PAH clearance = (urine PAH conc x urine flow rate)/ serum PAH conc* PAH clearance = (100 mg/dL x 1 mL/min)/ 0.2 mg/dL = 500 RBF = 500/(1-0.5) = 1,000 mL/min #1556

62 yo female hospitalized for 2d hx of MI sxs and is confirmed upon testing. On 5th day, she dies suddenly despite adequate resuscitation. What is the most likely CoD in this pt?

*Profound Hypotension* Pt died of profound hypoTN due to *ruptured Lv free wall*. This tends to occur *5-14d* after large anterior transmural MI. Abrupt rupture leads to *hemopericardium and cardiac tamponade* #195

Elastin fibers w/in alveolar walls normally allows lung to stretch w/ active inspiration recoil w/ passive expiration. What explains this property of elastin?

*Interchain cross-links involving lysine* *Elastin* is a *fibrous connective tissue* that has similar assembly to collagen. Once outside the cell, *Lysine Oxidase* (requires Cu+2) *deaminates lysine* on tropoelastin, facilitating the formation of *desmosine cross-links* btwn neighboring polypeptides #1249

Pt has a solitary mass on R temporal lobe. What visual defect is most likely present?

*Left Homonymous Superior Quadrantopia* Half of the axons from the Lateral Geniculate Nucleus carry information from the lower retina and project into the temporal lobe (*Meyer's Loop*). *Lesions of temporal lobe* disrupt Meyer's Loop and causes *contralateral homonymous superior quadrantopia*. May also have other manifestations: aphasia, memory deficits, seizures, and hallucinations #8594

21 yo male is hit in L posterior chest wall. Images show 12th rib fracture. What structure is damaged?

*Left Kidney* #1700

55 yo male w/ poorly controlled HTN and T2DM c/o difficulty seeing. Had blurry vision for 2wks and 1d ago suddenly noticed a shadow across visual field of L eye. No other sxs. PERRL. Fundoscopy: flame-shaped hemorrhage in L temporal hemiretina. What neural structure is disrupted?

*Left Lateral Geniculate Body* Pt has *hypertensive hemorrhage in L. temporal hemiretina*, which receives information from *nasal field* #11685

Study comparing Drug A vs standard tx for prevention of recurrent PE. Absolute risk reduction for Drug A is 4%. Incidence of recurrent PE w/ standard tx is 6%. 24 pts developed recurrent PE on Drug A. How many subjects were in Drug A group?

*1,200* *ARR = Event Rate(control) - Event Rate(tx)* ARR = 4%; ER(control) = 6%; ER(tx) = ? *ER(tx) = ARR - ER(control)* ER(tx) = 0.06 - 0.04 ER(tx) = 0.02 *ERtx = # of events in tx/# of subjects in tx* *# of subjects in tx = # of events in tx/ER(tx)* # of subjects = 24/0.02 # of subjects = 1,200 #1175

74 yo male c/o several mos of choking spells, dysphagia, and cough. Has had recurrent episodes of pneumonia. PMHL HTN and osteoarthritis. Normal vitals. Pt has foul-smelling breath, but oropharyngeal and neck are normal. Barium swallow shows abnormality in upper esophagus. What is the mechanism of sxs?

*Cricopharyngeal motor dysfunction* Pt has a *Zenker Diverticulum*. Increased oropharyngeal pressure eventually results in herniation of pharyngeal mucosa through muscle weakness (false diverticulum) in the posterior hypo pharynx (Killian change) #279

62 yo male w/ MI demonstrated by his hx, sxs, EKG, and labs. Investigators designed a randomized control trial to test the hypothesis that drug B will decrease the mortality associated w/ acute STEMI compared to standard of care. To ensure that investigators will not miss a difference btwn drug B and standard of care, which would they maximize?

*1-B* Statistical *power (1-B)*, represents a study's ability to *detect a difference when one exists*. The probability of rejecting a null hypothesis when it is truly false. *Power depends on* sample size and the difference in outcome btwn the group tested. #1272

2 yo female w/ ambiguous genitalia. Born w/ clitoral enlargement and partial fusion of labioscrotal folds. High BP. 50th percentile for ht and wt. Fam hx --. Labs: hypoK+. 46XX. What enzyme is deficient?

*11B-Hydroxylase* Pt has *Congenital Adrenal Hyperplasia* b/c of *11B-Hydroxylase def.*; which is responsible for converting *11-deoxycorticosterone to corticosterone* and *11-deoxycortisol to cortisol* Labs: *high* aldosterone (hypoK+) and androgens (virilization); *low* glucocorticoids #611

64 yo male w/ c/o dizziness and gait instability. PMH: HTN, hyperlipidemia, and T2DM. 30 pack years. PE: nystagmus and dysdiadochokinesia. MRI shows extensive atherosclerosis of carotid and vertebral As and one in cerebellum. Histology of cerebral lesion shows neurons w/ eosinophilic cytoplasm and loss of Nissl substance. When did the cerebella insult occur?

*12-24 hr ago* Pt had an *Ischemic Stroke*. *"Red Neurons"* are seen at *12-24 hr w/ intense eosinophilic staining* -pyknotic nucleus #19

Calculate Filtration Fraction in pt assuming urine flow of 1.0 mL/dL. Urine labs: Cr 110.0 mg/dL, glucose 0, K+ 55.0 mEq/L, Uric Acid 15 mg/dL, and PAH 100 mg/mL. Serum labs: Cr 1.1 mg/dL, Glucose 80.0 mg/dL, K+ 4.0 mEq/L, Uric Acid 30 mg/dL, and PAH 0.2 mg/dL.

*20%* *FF = GFR/RPF* *GFR = Cr CL* *RPF = PAH CL* *CL = [(urine concentration)(urine flow rate)]/plasma concentration* Cr CL= (110.0 x 1)/1.1 = 100 mL/min PAH CL = (100 x 1)/0.2 = 500 mL/min FF = 100/500 = 20% #1555

Substance A is freely filtered by glomerulus and reabsorbed by renal tubules. Labs: Inulin clearance 100 mL/min, PAH clearance 500 mL/min, plasma concentration of substance A 0.5 mg/mL, and tubular reabsorption rate of substance A is 25 mg/min. What is the excretion rate?

*25 mg/min* *Excretion Rate = Filtration Rate - Tubular Reabsorption Rate* ER = FR - 25 mg/mL *FR = GFR x Plasma concentration* ER = (100 mL/min x 0.5 mg/mL) - 25 mg/mL ER = 25 mg/mL *GFR = inulin clearance* (this is b/c inulin is neither secreted nor reabsorbed) #2011

What component of viral genome replication is most likely inhibited by Zidovudine?

*3'-5' Phosphodiester bond formation* *Zidovudine* is a *nucleoside reverse transcriptase inhibitor* that binds reverse transcriptase incorporated as a *thymidine analog* and prevents DNA chain elongation -*must be phosphorylated* to be active #2019

W/ a SD of 0.5, normal distribution of 5.0, and CI of 95%, what are the limits?

*4.0 and 6.0* At 95% CI, you are 2 SDs At 99.7% CI, you are 3 SDs #1172

56yo female w/ 3yr hx of A-fib c/o HA and R homonymous hemianopia w/ macular sparing. Occlusion occurred in what artery?

*Posterior Cerebral Artery* *PCA* supplies occipital lobe, which contains the *striate or primary visual cortex*. The straits cortex receive information about the contralateral visual field from the ipsilateral lateral geniculate body via optic radiations. Macular is sparred b/c of collateral circulation from Middle Cerebral A. #8592

Researchers assess relationships btwn essential HTN and mutation in Na+ channel protein. Random population is selected and blood collected for leukocyte genotyping. Prevalence of HTN determined by mean BP measurements over 1wk. Based on this, they make an accurate association. What best describes this study design?

*Cross-Sectional Study* *Cross-sectional Study* (prevalence study) measures exposure and outcome. It has a *"snap-shot" design*--blood sample in the cause -limitation: a temporal relationship btwn exposure and outcome is not always clear #1276

26yo male c/o chest pains, palpitations, SOB, and sweating. Has been to ER twice in past month w/ similar sxs. PMH--. Vitals: BP 130/90, HR 90, and RR 20. EKG norm. He exclaimed that he "feels like he's going to die!" What is the next appropriate step in management?

*Benzodiazepine Administration* Pt has a *Panic Disorder* where the *sxs are unexpected and peak w/in minutes*. "Fear of dying" is an indicator. *Immediate tx*: Benzos. *Long-term tx*: SSRI/SNRI w/ or w/o cognitive-behavioral therapy. -answer is not "Pheochromocytoma" b/c he lacks episodic HAs and paroxysmal HTN--Pheo also doesn't induce sweating #11756

A meta analysis on the effect of cocoa intake on SBP revealed results: Total = -2.2 [-2.7,-1.3] What is the most appropriate conclusion?

*Cocoa intake was associated w/ a statistically significant decrease in SBP* The CI range [-2.7,-1.3] did not cross the null (0) so change is statistically significant #10672

Photoaging, inducing wrinkles, is ude to decrease of what?

*Collagen Fibril Production* *UVA* produces ROS that disrupts transcription factors. This leads to *decreased collagen fibril production*, increased matrix metalloproteinases, and *increased collagen cross-linking* -will see gradual thinning of epidermis #1860

71 yo female w/ hx of CHF c/o fatigue and muscle weakness. 3 wks ago, started on tx for CHF. Labs: hypokalemia. Doc adds another tx and her fatigue and muscle weakness resolves. Her new meds act where on the nephron?

*Collecting Duct* Pt was most likely started on *loop diuretics* (non-K+ sparring) for CHF. Doc added a K+-sparring diuretic (Aldosterone antagonist) #2005

A new test measuring homocysteine levels is created. The test is repeated 3 times w/ pt's blood sample, and the results are 11.8, 9.2, and 13.7 (w/ reference range of 4-14). What parameter is most likely low?

*Precision* *Precision* (reliability) is the ability of a test to reproduce identical or similar results w/ repeated measurements (#s are clustered together) #1278

35 yo male was fixing up a 1960 convertible in his garage, while it was running, and the door was closed. He's found unconscious. What changes to arterial blood will be found? (%carboxyhemoglobin, PaO2, and % methemoglobin)

*40% Carboxyhemoglobin; 95% PaO2; 1% Methemoglobin* *CO* binds Hb about 250x more tightly than O2, *decreasing the number of available binding sites*. This then causes *increaed HBCO. Decreasing available Hb* causes *decreased O2 carrying capacity and O2 content*, but it does not affect *the amount of O2 dissolved in plasma*, which is represented by *PaO2*. Also causes L. shift. -*Methemoglobin* is only formed b/c of drugs (Dapsone or Nitrites) or genetic defects #1545

What is the number needed to harm if new drug has 40 alive and 60 dead in 1yr and standard drug has 51 alive and 69 dead in 1yr?

*40* *Number Needed to Harm = 1/Absolute Risk Increase* *Absolute Risk Increase = Adverse event rate in experiment - Adverse event rate in control* *AERE = #adverse events/# pts treated* AERE = 60/100 = 0.60 *AERC = #adverse events/# pts treated* AERC = 69/120 = 0.575 ARI = 0.60 - 0.575 = 0.025 NNH = 1/0.025 = 40 #1231

Liver biopsy shows extensive lymphocytic infiltrate and granulomatous destruction of interlobular bile ducts. Biopsy was taken from what kind of pt?

*45 yo female w/ a long hx of pruritus and fatigue who passes pale stools and xanthelasma* Pt has *Primary Biliary Cirrhosis*, a chronic autoimmune disease characterized by portal tract infiltrate resulting in *granulomatous destruction of intrahepatic, interlobular bile ducts* #403

34 yo male treated for acute leukemia develops oliguria. Serum Cr 2.7. Renal biopsy: multiple uric acid crystals obstructing renal tubular lumen. The principle site of uric acid precipitation would be where?

*Collecting ducts due to low urine pH* *Uric acid* precipitates in *acidic environments* and the lowest pH is found in *DCTs and CDs* -even if the PCT was unable to reabsorb uric acid, this would not induce precipitation due to the alkaline environment #1050

52 yo smoker c/o 2 wks of malaise, SOB, and decreased appetite. PMH of bicuspid aortic valve and HTN. Vitals: 102.2F and BP 140/80. PE: systolic ejection murmur at R upper sternal border (old) and new decrescendo diastolic murmur at 3rd intercostal space at L sternal border. Blood cultures: Streptococcus bovis. Additional work-up should focus on what?

*Colonic Neoplasia* Pt has *Subacute Bacterial Endocarditis*. -*S. bovis* is normal flora of colon and is associated w/ *colonic cancer* #1001

Newborn w/ growth retardation has low-set ears, a small mandible, and a prominent occupy. Neonate has a weak cry and hypertonia of extremities, including clenched fists w/ 2nd and 5th digits on top of 3rd and 4th digits. Cardia auscultations: harsh, 4/6 holosystolic murmur best heard at L sternal border. What is the most likely chromosomal abnormality?

*47, XX, +18* *Edward Syndrome (Trisomy 18)* presents w/ micrognathia, low-set ears, prominent occiput, and *rocker bottom feet*. Will see hypertonia as seen w/ *clenched fists w/ overlapping fingers*. Anomolies: cardiac (*VSD and ASD*), horseshoe kidneys, or GI (Meckle's or Malrotation) #1823

What is the fx of DNA Poly III?

*5' -> 3' DNA synthesis* *3' -> 5' Exonuclease activity*--this allows for *mismatch repair* during DNA replication. (*Prokaryotes only*) #1435

In response to ischemic injury in a MI, ATP levels w/in cardiomyocytes drop. At what time point would myocardium stop contracting?

*60 seconds* Even though ATP levels remain relatively constant for the first few minutes of ischemia, ATP is rapidly depleted and lactate levels increase. Ischemia <30 minutes is when loss of contractility is irreversible. Adenosine from ATP breakdown attempts to vasodilate and help coronary blood flow to meet O2 demand. However, 1/2 cellular stores of Adenosine are lost at 30 min. #42

10yo male immigrant c/o ataxia, myoclonus, and visual problems. He's been acting strangely and has had difficulty w/ school work. Brain biopsy: RNA virus w/ hemagglutinin cultured. Dx?

*Subacute Sclerosing Panencephalitis* *Measles*, a part of the Paramyxoviridae, uses *hemagglutinin* for adhesion and *matrix protein* for assembly. *Subacute Sclerosing Panencephalitis* is thought to be due to *absent of mutated matrix protein* #910

TP 10, TN 975, FN 990, and FP 25. How many pts are needed to be treated w/ superstatin, compared to control, to prevent one additional MI?

*67* *Number Needed to Treat = 1/Absolute Risk Reduction* *ARR = Control Event Rate - Experimental Event Rate* *Control Event Rate = FP/(FP + TN)* CER = 25/(25 + 975) = 0.025 *Experimental Event Rate = TP/(TP + FN)* EER = 10/(10 + 990) = 0.01 ARR = 0.025 - 0.01 = 0.015 *NNT = 1/0.015 = 67* A low NNT indicates a good drug #1174

A pt is started on a subcutaneous insulin that's a recombinant human insulin w/o any amino acid modification. What is its duration of action?

*7 hours* *Regular Insulin* has a half-life of 5 min and allows for rapid adjustment of glucose levels. Its typically used along w/ NPH (also w/o amino acid modification). It works w/in 30 min, peaks in 2-4 hrs, and lasts 5-8 hrs. #600

37 yo male has jet lag b/c of numerous trips from America to France in 3mos. Which hypothalamic nuclei is responsible for improvement?

*Suprachiasmatic Nuclei* This mediated circadian rhythm via input from photosensitive ganglion and regulates pineal gland #8573

Alcoholic is hospitalized. Which signs and sxs will most likely present earliest?

*Tremulousness* Acute EtOH increases GABA, but *chronic EtOH downregulates GABA Rs.*; *Tremulousness is most common initial finding* #870

What is the cumulative incidence? Population is 4,000,000. Beginning of year there were 20,000 cases. At end of year, 7,000 new cases and 1,000 deaths assoc. w/ condition. Another 40,000 deaths from other causes.

*7,000/3,980,000* *CI=# new cases/(General pop - # people already w/ disease)* *CI* is the proportion of at-risk individuals who contract the disease over the specified period. #1270

A knockout mouse's skeletal muscle fibers fail to contract in response to a substance normally released from Sarcoplasmic Reticulum. What is deficient?

*Troponin* Calcium from SR binds Troponin C, Tropomyosin shifts to expose actin binding sites for myosin, allowing for contraction to occur. #7592

A previously healthy 8yo male is vomiting and lethargic. Pt has been w/o food for 24hrs on a hike. He became weak and was carried for the last mile. PE: appears listless and mild hepatomegaly. Labs: Glucose 30 (low), Acetoacetate 0, AST 341 (high), and ALT 412 (high). Chid begins seizing. What enzyme is deficient?

*Acyl-CoA Dehydrogenase* Pt has *Medium Chain Acyl-CoA Dehydrogenase (MCAD) Deficiency* presenting as *hypoketonic hypoglycemia* after a period of fasting. Pt cannot conduct *FA B-oxidation* in mitochondria. He cannot convert *Acyl-CoA -> Trans-enol CoA and FADH2*. Tx: do not fast and administer glucose during period of illness #1888

Pt w/ fever and painful mouth ulcers presents. He's on MTX for psoriasis and takes his meds too often. PE shows multiple aphthous ulcers in oropharynx. Labs: decreased Hb, platelet, and WBCs. What is the next best step in management?

*Administer Folonic Acid (leucovorin)* *Leucovorin* is used in early intervention and is a form of folate that does not need to be converted to THF by DHFR. -can be added to 5-FU to potentiate tx against colorectal cancer #1818

What is a poor prognostic factor of PSGN?

*Adult Onset* *Increasing age* is the most important *poor px factor* of PSGN b/c only 60% of adult cases resolve completely. Pre-existing kidney disease is another poor px factor. #25

44 yo truck driver c/o a few hrs of PE sxs. He smokes 2 ppd. Vitals: 97F, BP 116/76, HR 102, RR 22. BMI 31. Cardiopulmonary exam normal. What would be seen on blood gas? (pH, PaO2, PaCO2, and plasma HCO3-)

*7.57 pH; 65 PaO2; 26 PaCO2; 23 plasma HCO3-* *PE* causes *hypoperfusion* of affected pulmonary parenchyma, leading to a *V/Q mismatch*. Worsening of V/Q mismatch causes significant *intrapulmonary R->L shunting*. This *hypoxemia* induces a *hyperventilation* that *cannot significantly improve blood oxygenation*. The hyperventilation increases CO2 removal, leading to *hypocapnia and RR alkalosis*. The *HCO3- remains normal in the acute phase*, but metabolic compensation occurs after 48hrs #1981

Antibiotic follows 1st order kinetics and has Vd of 70L and a Clearance of 0.5 L/min. How much should be administered every 6 hrs to maintain a steady state of 4 mg/L?

*720 mg* *Maintenance Dose = (Cpss x Clearance)/(Bioavailability Fraction)* -BF = 1 in IV infusion Maint Dose = (4 x 0.5)/1 Maint Dose = 2 mg/min For 6hr intervals: (2 mg/min)(60 min/hr)(6 hrs) =720 mg #8291

Test A is for dx of MI. TP 200, TN 80, FN 120, and FP 50. Pt has +Test A. Assuming his pretest probability is equivalent to the prevalence of MI in the study, what is the probability the pt has an MI?

*80%* *Positive Predicative Value = TP/(TP+FP)* PPV = 200/(200+50)=80% *PPV*, unlike specificity and sensitivity, *changes w/ prevalence* -*increased disease prevalence*=> increased PPV -*decreased disease prevalence*=> decreased PPV #1232

A periappendiceal abscess would most likely culture what microbe?

*Bacteroides fragilis* -common G-- anaerobic bacillus -others that cause intraabdominal abscesses: Escherichia coli, Enterococci sp., and Streptococci sp. #7573

A new test for dementia is created. A pt's test results are --. A study assessing the test's efficacy had a sample size of 200, in which prevalence of dementia is 50%, shows a specificity of 80% and sensitivity of 90%. Assuming pretest probability is equivalent to disease prevalence, what is the probability the pt does not have dementia?

*89%* *Negative Predictive Value = TN/(FN + TN)* TP = 90 FN = 10 FP = 20 TN = 80 NPV = 80/(10 + 80) = 89% #1233

53yo male w/ gastric cancer undergoes complete gastrectomy w/o complications. He must receive life-long administration of what substance?

*A water soluble vitamin* -there's no acidity to remove B12 from animal protein and no parietal cells to produce intrinsic factor so no B12 is absorbed! -answer is not "hydrolyzed-protein" b/c protein metabolism does not require HCl and pepsin b/c pancreatic enzymes can pick up the slack #1605

Construction worker w/ progressive constipation, SOB, conjunctival pallor, and decreased concentration. Labs: microcytic anemia, increased lead, and increased zinc protoporphyrin. What's seen on blood smear?

*Basophilic stippling* -Lead poisoning -Lead inhibits heme synthesis (aminolevulinate dehydrates and ferrochelatase) #1156

Pulsus Alternans

*Beat-to-beat variation in QRS complex* due to swinging motion of heart in fluid -cardiac tamponade

60 yo female c/o fatigue and chronic weakness. Undergoes Metyrapone stimulation test. There's increased urinary excretion of 17-hydroxycorticosteroid following Metyrapone administration. What mechanism is responsible?

*ACTH Surge* *Matyrapone stimulation test* assesses HPA axis integrity by *blocking cortisol synthesis* via inhibiting *11-B-hydroxylase* conversion of *11-deoxycortisol -> cortisol* in zone fasciculata (does not inhibit pituitary ACTH secretion). Increased 11-deoxycortisol is converted by the liver into *17-hydroxycorticosteroids* that accumulate in the urine. -increased 11-deoxycortisol and urinary 17-hydroxycorticosteroid-> normal HPA axis #608

Experiment where an animal inhaled noxious odor caused the release of a pentapeptide w/ strong affinity to delta and mu Rs. Which substance probably has a common molecular origin?

*ACTH* *B-endophin* is an endogenous opioid peptide dx from *Proopiomelanocortin (POMC)*. -POM is also a precursor for *ACTH and MSH* #775

What cancers are Down syndrome pts at increased risk of getting?

*ALL>AML* #1599

Which statistical method is best for comparing one variable amongst 4 groups of 200 pts?

*ANOVA* is used to determine significance btwn the means of 2 or more independent groups. Tests null hypothesis that all groups are random samples of same population. #8519

Pt is started on IV tx. Several minutes after administration, she experiences an anaphylactic reaction. What is elevated in her serum?

*Tryptase* Anaphylaxis results from widespread *mast cell and basophil degranulation* and resultant *histamine and tryptase* (mast cell only) *release* #2068

Family has a novel gene disorder characterized by increased insulin and frequency hypoglycemia due to even brief fasting. They have a mutation in K+ channel in pancreatic B cells. K+ channels are overly sensitive to their normal, activity-modulating regulatory substance, causing hypoglycemia. What substance directly binds to those channels?

*ATP* Glucose enters *B cells* via *GLUT-2*->glycolysis->TCA->*ATP*. The buildup of ATP then goes over to the *ATP-sensitive K+ channel* that normally *effluxes K+* and the K+ channel closes. *High ATP/ADP ratio* leads to decreased K+ efflux and *membrane depolarization*-> opens v-gated Ca+2 channels->Ca+2 influx-> *insulin release* #1009

Elderly pt has sudden onset palpitations and dyspnea. EKG shows HR 120, irregular rhythm, narrow QRS, and no P waves. What physiologic factors determines the ventricular contraction rate in this pt?

*AV Node Refractory Period* Pt is in *A-fib w/ rapid ventricular response*. See EKG results above for what A-fib looks like. Rapid, irregular atrial depolarizations signal to the AV node. The pace is now set by AV node refractory period. Average ventricular rate in A-fib is btwn 90-170 bpm. #1977

Heart action potential velocity is measured at 4 points: 0.05, 0.3, 1.1, and 2.2 m/sec. What locations corresponds to these points, respectively?

*AV node, ventricular muscle, atrial muscle, and purkinje system* Fastest to slowest: Purkinje system-> atrial muscle-> ventricular muscle-> AV node (Park At Venture Avenue). Slow AV node allows for ventricular filling. Fast purkinje system ensures ventricles contract in a bottom-up fashion. #1513

HIV pts cannot take what medication if they are HLA-B57:01 +?

*Abacavir* *Abacavir* is a nucleoside reverse transcriptase inhibitor that may induce *Abacavir Hypersensitivity Reaction* if someone is *HLA-B57:01 +*. It results in a *Typer 4 Hypersensitivity* that's characterized by fever, malaise, GI sxs, and a *delayed rash* #11590

Cross-Sectional Study

"Prevalence Study"; simultaneous measurement of exposure and outcome

Intestinal-Type AdenoCA

"Rapid intraluminal expansion"; well-formed glands; lesion may ulcerate/bleed w/ biopsy

Laparotomy on a 35yo WM w/ abdominal pain shows chalky white lesions in the mesentery. Histo: fat cell destruction and Ca+2 deposition. Dx?

*Acute Pancreatitis* -pancreatic enzymes induce fat necrosis and Ca+2 deposition #439

Accuracy

(validity) The ability of a test to measure what it is supposed to measure (stays w/in reference range)

Riboflavin

(B2) Mitochondrial e- carrier (FMN;FAD) Def= angular cheilosis, stomatitis, and glossitis

Niacin

(B3) e- transfer rxns (NAD;NADP) Def= dermatitis, dementia, diarrhea, and peripheral neuropathy

Pyroxidine

(B6) Transamination of aas Def= cheilosis, stomatitis, and glossitis

Calculate odds ratio of developing an arrhythmia if 20/90 pts on B-blockers develop arrythmias and 30/70 pts not on B-blockers develop arrhythmias.

*(20 x 40)/(70 x 30)* *Odds Ratio = (TP x TN)/(FP x FN)* -Exposed odds of developing an arrhythmia = 20/70 -Unexposed odds of developing an arrhythmia = 30/40 #1205

5 yo male w/ poor wt gain is noted to have bulky and greasy stools. Jejunal biopsy shows normal intestinal architecture, but enterocytes contain clear or foamy cytoplasm that is more prominent at tips of villi. What dx?

*Abetalipoproteinemia* Pt has *Abetalipoproteinemia*, which is due to impaired formation of *apolipoprotein B-containing lipoproteins*. Will see accumulation of lipid by enterocytes on biopsy. This is an *AR* loss of fx mutation in the *MTP gene*, which fxs as a chaperone protein necessary for *proper folding of apoB* and *transfer of lipids to newly formed CMs and VLDL*. -Labs: very low TGs and cholesterol; absent CM, VLDL, and apoB -deficiency in fat soluble vitamins and essential FAs=> acanthocytes and neurological abnormalities (ataxia and retinitis pigmentosa) -ApoB-100 in VLDL; ApoB-48 in CM #327

Infant w/ persistent vomiting that is initially clear and becomes bilious. Normal vitals and abdomen exam. Normal rotation of gut. Pancreatic tissue encircles duodenum. What caused this?

*Abnormal migration of ventral pancreatic bud* Pt has an *Annular Pancreas* (forms around 2nd part of duodenum) Normal process: ventral bud is a foregut dx that rotates behind duodenum in 7th wk and fuses w/ dorsal bud at 8th wk. #438

4 yo pt w/ CF. What doe the CF mutation most commonly cause?

*Abnormal post-translational processing of a TM protein* Most common CF mutation is a 3 bp deletion of Phe (*deltaF508*), causing impaired post-translational processing--*detected by ER* and is degraded by proteasomes. #802

1 mo Caucasian male w/ hx of persistent jaundice experiences muscle rigidity, lethargy, and seizures. Which cause of hyperbilirubinemia produced this pt's neurologic sxs?

*Absent liver conjugation enzymes* Pt has *Crigler-Najjar Syndrome Type 1*, an *AR disorder* due to a *genetic lack of the UGT enzyme* required for *conjugation of bile*, leading to *unconjugated hyperbilirubinemia*. *Unconjugated bilirubin* is not water soluble and is highly bound to albumin so it is not excreted in the urine. Instead, it is *deposited in various tissues*, especially the brain=> *Bilirubin encephalopathy* (kernicterus) #363

36 yo female w/ breast lumps undergoes biopsy. They're cytokeratin +. Special IHC stain shows over expression of a 185 kD glycoprotein that spans the cell membrane and has tyrosine kinase activity int he intracellular domain. What is the fx of this protein?

*Accelerates cell proliferation* *HER2 oncogene* encodes an epidermal growth factor receptor w/ tyrosine kinase activity in intracellular domain. *HER2+* is associated w/ *worse px*. Tx: *Trastuzumab* #2093

Where on tRNA would aminoacyl tRNA synthetase add on Lysine residues?

*Acceptor Stem of tRNA* The *Acceptor Stem* is created through the base pairing of 5' and 3' nucleotides. It contains a *CCA tail* at the *3' end* and serves as the *amino acid binding site*. This acceptor stem helps ensure correct tRNA recognition by the proper aminoacyl tRNA synthetase. #1428

3 yo female w/ c/o several mos of fatigue and difficulty walking. She ambulates normally but quickly becomes fatigued. Has not been ill recently. Hx of developmental delay but otherwise normal. Vitals: normal. PE: mildly decreased strength in all extremities w/o ataxia. Cardiac: 1/6 systolic murmur and S3 gallop. Labs: Gluc 37 mg/dL (low) and CK 304 U/L. Muscle biopsy shows low carnitine content. What substance has decreased synthesis?

*Acetoacetate* Pt has *Primary Carnitine Deficiency* due to a defect in the *enzyme that transports carnitine across mitochondrial membrane*. FAs can no longer go to mitochondria as acyl-carnitine and there is *decreased B-oxidation of FAs->acetyl-CoA*. Liver is unable to synthesize ketone bodies (*Acetoacetate and B-hydroxybutyrate*) w/ hypoglycemia -sxs: muscle weakness, cardiomyopathy (S3), hypoketotic hypoglycemia, and increased muscle TGs #1886

35 yo female w/ c/o n/v and fever. Sxs began 24 hr ago and cannot consume substance. She has a 3yo daughter w/ similar sxs 2d earlier but she is fine now. Labs: blood glucose 82 despite 24hr fasting. Blood glucose is facilitated by hepatic conversion of pyruvate->glucose. What stimulates the first enzyme is this process?

*Acetyl-CoA* During *Gluconeogenesis*, *Alanine and Lactate* are converted to *pyruvate*. Pyruvate goes to *mitochondria* to be catalyzed by *Pyruvate Carboxylase (w/ B7)* to become *Oxaloacetate*. PC is induced by *Acetyl-CoA*--which is increased b/c of B-oxidation of FFAs #1034

5mo male w/ c/o poor feeding. Mom says he cannot keep his head up and suckling has decreased in strength. Wt in 5-10th percentile and length and head circumference in 25th percentile. PE: hepatomegaly and hypotonia in extremities. Cardiac PE: S3 gallop. CXR: severe cardiomegaly. Muscle biopsy: enlarged lysosomes containing PAS+ material. What enzyme is deficient?

*Acid a-glucosidase* Pt has *Pompe Disease* due to deficiency in *acid a-glucosidase*, the enzyme required for *breaking down glycogen in acidic lysosomes*. This is especially prevalent in hepatocytes and myocytes, which is seen by accumulation of glycogen in liver and muscle -classic sxs: *cardiomegaly, hypotonia*, macroglossia, and hepatomegaly -Labs: *normal blood glucose* #1023

15 yo female w/ c/o fatigue and sore throat. PE: anterior and posterior cervical LAD and splenomegaly. Peripheral blood smear shows large cells w/ abundant cytoplasm, eccentrically placed nuclei, and cell membrane that appears to conform to borders of neighboring cells. This atypical cell is most likely what?

*Activated CD8+ Cytotoxic Lymphocyte* Pt has *Infectious Mononucleosis* due to *EBV infection*. EBV infects *B cells* by binding to *CD21 R.* *CD8+ lymphocytes* clonal expand in Infectious Mononucleosis and you see *reactive (atypical) CD8* -CD21 is a R. for C3d #7643

34 yo female c/o fatigue, exertional dyspnea, and cough. PMH-- and no tobacco use. Vitals normal w/ RR 22. Pulmonary PE: normal air exchange w/ scattered crackles and no wheezes. Pt has nontender cervical LAD. Serum Ca+2 12 (increased). CXR: scattered nodules and parenchymal infiltrates. LN biopsy shows noncaseating granulomas. What is the cause of increased Ca+2?

*Activated Macrophages* Pt has *Sarcoidosis*. Granulomatous disorders *activate macrophages* and cause *PTH-independent* production of *1,25 Vitamin D*, causing increased intestinal absorption of Ca+2 -especially AAs for Sarcoidosis -extrapulmonary sxs: skin lesions, anterior/posterior uveitis, and Lofgran Syndrome -CXR: bilateral hilar adenopathy #984

54yo male has a palpable neck lump determined to be "cold". Fine-needle aspiration shows spindle-shaped cells in an amorphous background. Pt's calcitonin levels are increased. What gene change is responsible?

*Activating mutation of RET proto-oncogene* *Medullary Thyroid Cancers* are tumors of *parafollicular C cells*. Sporadic and familial (Men 2a/b) are all associated w/ *RET photo-oncogene* mutations (this is a membrane-bound Tyrosine kinase R.) #1660

45 yo male w/ DM. He's getting started on a tx that alters glucose metabolism w/in the liver by increasing the concentration of fructose-2,6-bisphophate w/in hepatocytes. What conversion will be inhibited by increased levels of this metabolite?

*Alanine->Glucose* *Fructose-2,6-Bisphosphate* helps control the balance btwn *gluconeogenesis and glycolysis* by *+ stimulation of Phosphofructokinase-1* and *--stimulation of Fructose-1,6-Bisphosphatase* (fed state) for conversion of *F-6-P->F-1,6-BP*. -insulin *+stimulation* of PFK-2 to *increase F-2,6-BP* and stimulate conversion to pyruvate -increased F-2,6-BP: *--gluconeogenesis*=> decreased conversion of Ala->Glucose #1031

Hereditary Fructose Intolerance

*Aldolase B deficiency* Pres: hypoglycemia and vomiting after fructose ingestion. Failure to thrive and liver and renal failure Buildup of *Fructose-1-Phosphate*

What serum marker is used for Hepatocellular CA?

*Alph-Fetoprotein* -also for germ cell cancers #56

Thinning of glomerular BM

*Alport Syndrome* -benign; assoc. w/ microscopic hematuria -presents w/ hearing loss, ocular abnormalities, and progressive renal insufficiency

HIV pt w/ active TB infection is started on 4 combo tx. 3 wks f/u and he c/o red urine and red stained contacts. TB is found to be resistant to antibiotics. What explains the resistance to the drug responsible for pt's sxs?

*Altered structure of enzymes involved in bacterial RNA synthesis* Taking *Rifampin* -MoA: inhibits bacterial DNA-dep-RNA-Poly -SEs: rash, cytopenia, and red-orange body fluids #1226

Why would cancer cells have abnormal FasR that are only found in the cytoplasm and not in the cell membrane, despite the lack of a receptor gene mutation?

*Alternative Splicing* -they spliced out the TM domain to evade apoptosis #11913

45 yo male w/ 1d hx of severe dyspnea on exertion. Dyspnea worsens throughout d. No trauma. PMH and meds--. 20 pack yr smoking hx. Vitals: BP 110/60 and HR 90. Blood gas: PaO2 54 (low) and PaCO2 26 (low). What is the cause of blood gas abnormality?

*Alveolar Hyperventilation* Acute-onset dyspnea, hypoxemia, and hypocapnia is consistent w/ *Alveolar Hyperventilation*. *PaCO2 is inversely proportional to alveolar ventilation*, and is considered the main indicator. This cane be created by V/Q mismatch that causes decreased O2 and CO2 exchange. Hypoxemia-> peripheral chemoreceptors-> increased RR-> hypocapnia but hypoxemia persists b/c of impaired O2 transport-> increased A-a gradient #528

16 yo male w/ c/o sudden onset of L-sided abdominal pain and hematuria. Pain waxes and wanes in intensity and does not improve w/ position change. Lengthy hx of similar sxs, but 1st time w/ hematuria. PE: CVAT. Microscopic exam of urine shows hexagonal crystals. What lab abnormality is present?

*Aminoaciduria* Pt has *Cystinura*, and *AR disorder* w/ decreased activity if Na+-independent dibasic aa transporter found in *PCT* and formation of *cysteine stones*. -*Sodium Cyanide-Nitroprusside test* to detect cystinuria; + = red-purple -tx: *urinary alkalinization* -stones are *radio-opaque* -urinary pH <7.0 #814

22yo female c/o 5d hx of nauseate, constipation, and severe abdominal pain. She also has anxiety, difficulty concentrating, poor sleep quality, and tingling of limbs. She's had similar episodes before in the past. She's been restricting diet to lose wt. PE: abdomen is soft, nontender, and nondistended. Bowel sounds decreased. She receives infusion of heme and that resolves sxs. This downregulated what enzyme?

*Aminolevelinate Synthase* Pt has *Acute Intermittent Porphyria*, an *AD* disease due to *Porphobilinogen Deaminase deficiency*. Tx w/ *heme or glucose* b/c they *downregulate* hepatic *ALA synthase*, the rate-limiting enzyme in heme synthesis -note: ALA Synthase can be induced by: Barbituates, anti-epileptics, chronic EtOH abuse, smoking, and *low calorie diet* (this pt) -Urinalysis: increased PGB and ALA #1338

65 yo male w/ new-onset confusion, suprapubic discomfort, lack of urine output. PMH: BPH, HTN, hyperlipidemia, and T2DM complicated by neuropathy. Hx of chronic insomnia. PE: afebrile, confused, and oriented only to self. A urinary catheter is placed and immediately 1L of urine is drained. What tx caused this?

*Amitriptyline* *TCAs* have strong *anticholinergic properties* that can lead to significant *adverse SEs*: confusion, constipation, and acute urinary retention. #575

59 yo male w/ fatigue and chronic back pain that began 3mos ago and mainly occurs w/ position changes. PE: midline tenderness over middle to lower back. Lab: normocytic anemia and mild hyperCa+2. Bone marrow biopsy: plasma cells w/ clock-faced nuclei. Pt is at increased risk of what?

*Amyloidosis* Pt has *Multiple Myeloma* Increased *bone resorption* b/c of IL-1 and IL-6 production; lytic bone lesions via osteoclasts *HyperCa+2* from bone resorption *Monoclonal Ig production* increases susceptibility to infection; Bence-Jones Proteins; Rouleux formation *AL Amyloid* forms b/c of monoclonal Ig light chains; contributes to renal failure and increases risk of Amyloidosis *Renal Failure* from BJ proteins, AL Amyloid, hyperCa+2, and macrophages #872

54yo female c/ PMH of breast cancer and radical mastectomy experiences chronic lymphedema in her R arm postop. What is the most likely etiology of her current skin lesions?

*Angiosarcoma* *Chronic Lymphedema* is a risk factor for *cutaneous angiosarcoma* #1937

Immigrant w/ a titer of anti-Hep A IgM -- and anti-Hep A IgG +. Not immunized. What do these lab findings say?

*Anicteric viral infection as a toddler* Asymptomatic pt w/ anti-Hep A IgG means *prior infection*. -80% of cases are asymptomatic -there is no carrier state for Hep A #373

Elderly female w/ episodic loss of urine for several months. She says it starts as an urge to pee and cannot make it to the bathroom in time. PE is unremarkable. There is significant detrusor muscle instability noted. Appropriate tx includes an agent that affects what?

*Antagonism of muscarinic cholinergic Rs.* *Urge incontinence/overactive bladder syndrome* is caused by uninhibited bladder contractions. *Anticholinergics* (oxybutynin) antagonize M3 Rs. on smooth m. of bladder. *M3 antagonism* causes decreased IP3 production, decreased Ca+2 release, and smooth muscle relaxation. #8249

Life-long smoker and nickel miner presents w/ worsening SOB. Develops RR failure. Dies and upon autopsy it is found that his bronchi walls are thickened, PMN infiltrates, mucous gland enlargement, and patchy squamous metaplasia. What is his greatest risk factor for disease?

*Behavioral (life-long smoking)* *Chronic bronchitis*: chronic productive cough w/ airflow limitation. Primarily caused by tobacco smoking. Ddx: nickel inhalation is a carcinogen associated with nasal or lung cancer. #524

12 yo male presents to ER w/ c/o difficulty breathing, wheezing, and nonproductive cough. He's visited the ER several times in the past yr b/c of similar sxs. PE: decreased bilateral breath sounds, prolonged expiration, and end-expiratory wheezes. CXR: hyperinflated lungs w/ no infiltrate. He's treated w/ B-agonists and corticosteroids. Sxs improved and started on tapered-dose oral corticosteroids. Comes to ER 2wks later w/ severe RR distress w/ similar sxs and requires endotracheal intubation. What tx mechanism would prevent future events?

*Anti-IgE Abs* Pt who fails tx to inhaled B-agonists and corticosteroids and required control via oral glucocorticoids, are found to be resistant to Leukotriene antagonists and Theophylline, so they're treated w/ *Omalizumab*, and *anti-IgE mAb* that binds IgE and prevents interaction w/ mast cells and basophils #2128

Adult dx w/ idiopathic membranous nephropathy develops edema, sudden L-sided flank pain, and gross hematuria. Vitals normal. PE shows L-sided varicocele and L-sided CVAT. Urinalysis: proteinuria and hematuria Labs: Increased LDH Urinary loss of what predisposed this pt to his acute condition?

*Antithrombin III* Pt's *nephrotic syndrome* (IMN) allowed for proteinuria (loss of antithrombin III), leading to a hypercoagulable state. This then caused the pt to receive a *renal v. thrombosis* as seen by the flank pain, hematuria, and increased LDH. -new onset varicocele is also indicative of RVT -L. Renal V. crushed by Aorta or SMA #26

52 yo male c/o increasing fatigue over last 2wks, as well as exertion dyspnea and occasional HAs. What condition is consistent w/ pt's findings?

*Aortic Regurgitation* *Aortic Regurg* is a *diastolic murmur* that is best heard at the *L sternal border*. AR is most commonly b/c of aortic root dilation or bicuspid aorta, in developed countries #2105

What is the best determinant of bioavailability of a drug when measuring plasma concentration of the drug taken orally and via IV?

*Area under the oral curve divided by the area under the IV curve* This reasoning works only if dosage for oral and IV are equal. IF not, you have to do: *Bioavailability = (oral AUC x IV dose)/(IV AUC x oral dose)* -oral bioavailability is affected by: gastric acidity and mobility, absorptive ability of gut, presence of other material in gut, and first pass metabolism #1709

43 yo male w/ CAD. Coronary angiography shows mild luminal irregularities but no significant obstructive lesions. Each infusion during procedure results in dilation of epicardial vessels. A reaction involving what amino acid is responsible for observed dilation?

*Arginine* *Endothelium-dependent vasodilation* is mediated by ACh, Bradykinin, Serotonin, Substance P, and shear force. This stimuli *increases intracellular Ca+2* -> causing *activation of endothelial NO synthase* to synthesize *NO* from *Arg, NAPH, and O2*. NO then activates *guanylyl cyclase* to *increase cGMP*, thus activating *Protein Kinase G*, *decreasing intracellular Ca+2*, and *relaxation of vascular smooth muscle cells* #8563

Full-term neonate born w/ ambiguous genitalia and clitoromegaly. Labs: increased testosterone and androstenedione. Karyotype: 46, XX. US: normal-sized uterus. Mother experienced facial hair growth and voice deepening during pregnancy. What enzyme is deficient in neonate?

*Aromatase* *Aromatase* is the key enzyme in *steroidsynthesis*; it converts androstenedione to estrone and testosterone to estradiol. *Aromatase deficiency* is an *AR* disorder that manifests in early embryonal life w/ *high androgen and low estrogen* levels in a female fetus. *Maternal hirsutism* commonly occurs in pregnancy. *Females* will have *normal internal female genitalia and ambiguous external genitalia*. At puberty, they'll have primary amenorrhea, osteoporosis, and tall stature (delayed fusion of epiphyses) *Males* w/ aromatase deficiency will be tall w/ osteoporosis, but no genital abnormalities #955

65yo male missed his CHF f/u appointment b/c of an upset stomach that just wouldn't go away. He c/o disturbed color perception, anorexia, and n/v/d that have worsened in the past 2wks. He states that his CHF has been maintained on multiple meds. If the cause of this pt's sxs aren't treated, what complication may develop?

*Arrhythmia* *Digoxin Toxicity* can cause non-specific GI sxs, neurologic sxs (*color distortion*, weakness, confusion), and the most serious is *any cardiac arrhythmia*. Digoxin has a narrow therapeutic index. May see hypoK+, hypovolemia, and renal failure. tx: anti-Digoxin Ab fragments MOA: direct inhibitions Na+/K+ ATPase w/ indirect inhibition of Na+/Ca+2 exchanger (increase intracellular Ca+2 and vagal stimulation) #156

67 yo male w/ dyspnea, othopnea, and bilateral pitting edema. What is expected to be increased?

*Arteriolar Resistance* Pt has *CHF*, most likely both L- and R-sided. *CHF* is due to either *decreased myocardial contractility (systolic dysfunction)* or *inability of heart to relax for filling (diastolic dysfunction)*. Ultimately decreased CO. -decreased renal perfusion=> *activation of RAAS*=> AngII=> vasoconstriction => *increased arterial resistance and increased after load* xCHF is worsened by Aldosterone b/c it increased preload (increased blood volume) #843

34 yo female w/ c/o recurrent transient pulmonary infiltrates. Hx of bronchial asthma w/ severe exacerbations, especially in winter months. Currently asymptomatic. No other PMH and no travel. Meds: albuterol and medium-dose inhaled glucocorticoid. Afebrile. PE normal. CBC: eosinophilia. Chest CT: proximal bronchiectasis. Pt is colonized w/ what?

*Aspergillus fumigatus* *A. fumigatus* is low virulent and is not significant unless immunocompromised. Will colonize bronchial mucosa. Can cause *Allergic Bronchopulmonary Aspergillosis (ABA)*, which tends to occur in *corticosteroid-dependent asthmatics* -pts w/ ABA have: increased IgE, eosinophils, and IgE and IgG Abs to Aspergillus -proximal bronchiectasis #665

47 yo male presents w/ persistent fever, night sweats, and fatigue. He's dxed w/ CML. During chemotherapy, he starts to c/o HAs, scant nasal discharge, and a problem w/ his L eye. PE: tenderness to peranasal sinuses and L-sided orbital swelling and cellulitis. Mild protosis and ptosis of L eye are present. Biopsy of sinus mucosa shows fungal hyphae branching at acute angles and lots of RBCs. Pt is infected w/ what?

*Aspergillus fumigatus* Pt has *Fungal Rhinosinusitis* due to *immunosuppression*. He's at increased risk of *invasive aspergillosis* b/c of prolonged neutropenia from CML tx. It most commonly forms lung granulomas w/ development of fever, pruritic chest pain, and hemoptysis. Tx w/ Amp B. -note: Aspergillus fungal balls tend to invade pre-existing pulmonary cavitary lesions #105

3 yo male c/o erythematous, itching rash on cheeks, trunk, and arms that's associated w/ consumption of certain foods. This pt's condition is most closely associated w/ what other disorder?

*Asthma* Pt has *Atopic Dermatitis (Eczema)*, a chronic inflammatory disorder triggered by environmental factors. Presentation by age 5 and diaper area is usually spared. Older children have manifestations of *lichenification* in a *flexural distribution*. Dx cannot be made w/o *intense pruritis*. AD is thought to be caused by mutations in proteins of components of epidermis, *impairing skin's barrier fx*. Pts have *high serum IgE, peripheral eosinophils*, and high levels of cAMP phosphodiesterase in their lymphocytes. AD is similar to *allergic rhinitis and asthma* #876

At what lung volume is total pulmonary vascular resistance the lowest?

*At the end of expiration of tidal volume; Functional Residual Capacity* *Increased lung volume* causes alveolar expansion. This increases their length and decreases their diameter, *increasing alveolar vessel resistance* *Decreased lung volumes* causes extra-alveolar arteries and vessels to narrow, *increasing extra-alveolar vessel resistance* *Pulmonary vascular resistance* is the sum of alveolar and extra-alveolar resistances, thus both values will be at their middle at *FRC* #1620

54yo male had abdominal surgery. Doc gave him a drug that caused flushing, diaphoresis, and nausea. Vitals: BP 100/70 and HR 55. Pupils are constricted but reactive to light. This drug is given for what condition?

*Atonic Bladder* Sxs are consistent w/ a *cholinergic agonist*. Above is *Bethanechol*, which is used in non-obstructive urinary retention (atonic bladder) and *post-op ileus* (this case) #1362

Pt w/ Hypothyroidism has too high of a dose of Levothyroxine, as seen by near absent TSH. What does this put her at greatest risk of developing?

*Atrial Fibrillation* Long-term complications of *too high Levothyroxine* are: HTN, increased bone resorption, and *A-fib* (think about complications of hyperthyroidism). Hyperthyroidism can cause the *increased expression of B receptors*, which triggers the A-fib -*increased contractility*: increases EF and CO; increases myocardial O2 demand and angina; increases pulmonary artery pressure -*decreased afterload*: decreased SVR -*additional effects*: decreased diastolic pressure, increased systolic pressure, increased pulse pressure, and high output HF #14985

67 yo male hospitalized for syncopal episode preceded by dizziness. Pt had loss of consciousness but regained consciousness w/o disorientation 1 min later. EKG: bradycardia w/ regular rhythm and narrow QRS. There is desynchronized P waves and QRS complexes. What location is responsible for pacing of pt's ventricles?

*Atrioventricular Node* Based on the EKG findings of *asynchronous P waves and QRS complexes*, the pt most likely has a *Third Degree (Complete) AV Heart Block*. SA node causes atrial contraction and AV node causes ventricular contraction -*QRS complex is narrow* b/c ventricular depolarization precedes normally -AV node has a 45-55 bpm pace #1976

64 yo smoker c/o R shoulder pain that radiates to ipsilateral arm and weakness in R upper extremity. Sxs began 2mos ago and have worsened progressively. Neurologic exam normal. He has partial R-sided ptosis w/ fully intact extraoccular muscles. His pupils are asymmetric in dim light w/ 2 mm on R and 2 mm on L, but both reactive to light. Both pupils are more symmetric in bright light. Upper extremity has 3/5 strength and absent deep tendon reflexes. Autonomic dysfx is due to lesion where?

*Autonomic Ganglia* Pt has a *Pancoast Tumor* found in superior sulcus that's compressing and invading the *brachial plexus*, causing the UE dysfx. Involvement of the *cervical sympathetic ganglia* may lead to *Horner's Syndrome* (ipsilateral) #566

5wk old male c/o rapid breathing and tiring w/ feeds. Vitals: 98F, BP 76/38, HR 124, and RR 66. Cardio PE: hyperdynamic precordium, midsystolic rumble at L sternal border, and 3/6 holosystolic murmur at apex that radiates to axilla. Echocardiogram: defect at lower part of interatrial septum and IVS. What genetic condition is associated with this?

*Autosomal Trisomy* Pt has *Complete Atrioventricular Canal Defect*, which is most commonly seen in *Down syndrome*. *Failure of endocardial cushion fusion* results in *ostium primum ASD, VSD, and single AV valve*. Will see: HA, AV regurgitation, and increased pulmonary venous return #188

56 yo male w/ persistent L wrist pain. Pt was walking dog, fell forward, and landed on an outstretched hand. Pt has swelling on dorsal of L hand. Point tenderness over dorsolateral aspect of hand btwn tendons of extensor pollicus longus and extensor pollicus brevis. Pt is at greatest risk of what complication?

*Avascular Necrosis* *Scaphoid Fractures* are the most common carpal bone fracture. Often due to falling on outstretched hand or wrist hyperextension. -pt experiences *tenderness in anatomical snuff box* -increased risk of *avascular necrosis* of proximal pole (*radial A.*) #8670

55 yo male w/ advanced HIV c/o fever, wt loss, diarrhea, and weakness. Sxs started several wks ago and have worsened. PE: HSM and skin pallor is noted. Labs: CD4+ 40 and increased Alk Phos and LDH. CXR:--. Abdominal CT: HSM and retroperitoneal LAD. Blood cultures: acid-fast + that grows at 41C. Pt's infection could have been prevented w/ what prophylaxis?

*Azithromycin* Pt is infected w/ *Mycobacterium avium complex* that tends to hit CD4+ <50. The growth characteristics and widespread RES involvement differentiates it from other Myobacterium spp. They're resistant to normal TB drugs but are susceptible to *Azithromycin and Clarithromycin* #1312

41 yo female has + pregnancy test. LMP 12 wks ago. Has experienced extreme n/v for past month. Has 3 children via C-section. US shows echogenic intrauterine tissue w/o amniotic sac and multiple ovarian cysts. Curettage shows hydronic villi. What should be closely monitored?

*B-hCG* Pt has *Complete Mole* and you worry about malignant transformation (choriocarcinoma) -Increased B-hCG is assoc. w/: hyperemesis, pre-eclampsia, hyperthyroid, and theca-lutein cysts. Karyotype: 46 XX or XY (*paternal only*) IHC: p57-- No fetal tissue #791

35yo female diagnosed w/ Multiple Sclerosis several yrs ago has developed several sxs of spasticity: painful muscle spasms, stiffness in legs, urge incontinence, and spastic paraparesis and abnormal sensation below mid-thoracic region. What mono therapy would provide the best benefit for this pt's spams?

*Baclofen* *Spasticity* is defined as the increase in resistance to passive muscle movement or a velocity-dependent increase in tonic stretch reflexes. This is due to loss of UMN inhibitory control. *Baclofen* is a *GABA-B receptor agonist* for tx of spasticity -note: *Tizanidine*, an *a2-agonist*, is also effective #11458

35 yo female c/o several month of hearing loss and tinnitus in L ear. PMH:--. Does to use cotton swabs. PE: external ear normal w/ diminished L-sided hearing. Neurologic exam: L-sided facial numbness, asymmetric smile, and decreased afferent and efferent corneal reflex responses in L eye. There's an intracranial mass where?

*Between the cerebellum and lateral pons* Pt has an *Intracranial Schwannoma* located at the *Cerebropontine Angle* btwn the cerebellum and lateral pons. Sxs: 1) Impairment of *cochlear portion of VIII* causes *sensorineural hearing loss* and *tinnitus*; damage to *vestibular portion* causes *vertigo, nystagmus, and dysequilibrium* 2) Compression of *CN V* causes *loss of facial sensation* and paralysis of *muscles of mastication* 3) *CN VII* nonsense #1306

17 yo female w/ small, underdeveloped ovaries composed of connective tissue w/o follicles. What additional findings will be noted?

*Bicuspid valve, horseshoe kidney, webbed neck, coarctation of aorta, narrow palate, cubits values, and short stature.* Pt has *Turner syndrome*. 45X0 female w/o paternal X chr. -no breasts or menses -Labs: elevated LH and FSH #256

45 yo female w/ hx of SLE treated w/ multiple medications found head at home. BP 150/90. Records show progressive truncal obesity, facial plethora, and proximal muscle weakness. Labs: mild hyperglycemia. CoD: L. coronary A. mainstream thrombus. Evaluation of adrenal glands show what?

*Bilateral cortical atrophy* Pt has *iatrogenic Cushing's syndrome* b/c of prolonged glucocorticoid tx. -excess glucocorticoids inhibit entire HPA axis (decreased CRH, ACTH, and cortisol) -> bilateral cortical atrophy -> sudden stopping of meds may induce adrenal crisis Note: SLE and Cushing's increased risk of embolus #928

52 yo postmenopausal female w/ c/o several mo hx of episodic abdominal discomfort and nausea, especially after a fatty meal. PMH--. BMI 33. PE: normal abdominal exam. Liver span 8cm. Murphy--. Abdominal Xray shows no calcifications, but Abdominal US shows small, non-obstructive gallstone. Pt prefers medication over surgery. What tx is best?

*Bile Acid Supplement* Pt has *Cholesterol Gallstones* (most common). Normal, *bile acids and phospholipids* solubilize cholesterol. *Risk factors*: increased age, obesity, excess bile salt loss, female, and rapid wt loss. -admin of *hydrophilic bile acids* decreases cholesterol secretion and increases bile acid concentration, promoting gallstone dissolution -*gallbladder hypo mobility and mucous hyper secretion* also increases risk of stone formation #11739

46 yo male c/o 3d fever, SOB, pleuritic chest pain, and productive green cough. 20 pack yrs. PE: crackles at base of L lung. CXR: lower lobe consolidation. Micro: G+ lancet-shaped cocci in pairs. What biochemical characteristic does this bacteria have?

*Bile Solubility* *Streptococcus pneumoniae*: G+, alpha hemolytic, cat--, bile +, and optochin + #731

34 yo male c/o easy bruising, even w/ minor trauma. Also states that he has spontaneous bruising all over legs. Also c/o general fatigue, poor appetite, and dull pain and stiffness in his lower back and joints. PMH: Crohn's w/ partial bowel resection 1yr ago. 3mos ago antibiotics for anal fistula. Mother died of colon cancer at 56yo. PE: several ecchymosis on LEs. What is the most likely dx?

*Bile acid malabsorption* All of his sxs are manifestations of his *Crohn's disease*, which may have extra intestinal manifestations such as ankylosing spondylitis and peripheral arthritis. *Terminal ileum* is most often involved, which is the location of *bile acid absorption*. Decreased bile acid leads to *fat and fat-soluble vitamin malabsorption*. This will lead to *Vitamin K Deficiency* and subsequent vitamin k-dependent clotting factors #12047

45 yo male w/ minor laceration develops cellulite from a G+ cocci that grows in clusters. This organism synthesizes a protein as a part of its peptidoglycan cell wall that does what?

*Binds to the Fc portion of IgG* *S. aureus* has *Protein A* built into peptidoglycan and binds Fc portion of IgG to *prevent C' activation*. Thus, there is *decreased C3b production* and impairment of opsonization. #677

What is the MOA of Argatroban?

*Binds to thrombin active site* *Argatroban* is used as a *treatment for Heparin-Induced Thrombocytopenia* b/c *direct thrombin inhibitors* do not require anti-thrombin III to be active -note: HIT is most common w/ unfractionated heparin. #1078

What is the MOA of Ethosuximide?

*Blocks thalamic T-type Ca+2 channels* -alternate for absence seizures = Valproate; blocks Na+ channels and increases GABA #509

Female w/ n/v and L-sided chest pain that began 30 min ago w/ exertion. Hx of dyslipidemia and HTN. Fam hx of MI. Tender to chest palpation. EKG and cardiac enzymes normal. Stress test ordered. During test, what parameters is likely to be the most similar btwn the system and pulmonary circulation?

*Blood flow per min* In order to maintain blood flow through the body, blood flow/min in systemic must be close to pulmonary circulation. -true to exercise and rest -if blood flow pulm<systemic->L ventricle empties -if pulm>systemic->L ventricle overload #1528

65 yo male had recent travel to tour wool-processing plants in several Asian countries and now c/o ulcer w/ black eschar. The toxin causing edema is most similar to a toxin produced by what other bacterium?

*Bordetella pertussis* *Anthrax edema factor* works by *increasing cAMP* via acting on adenylate cyclase *and Pertussis' adenylate cyclase toxin* works in the same way #1101

Bilateral Facial N. Palsy

*Borrelia burgdorferi* (Lyme)

36 yo female c/o dyspnea and weakness. PMH --. Mother had similar sxs and died at 42 yo. Lung biopsy shows medial hypertrophy, intemal fibrosis, and decreased intraluminal diameter of the small branches of the Pulmonary A. Pt is scheduled for lung transplant. Which medication is she placed on until then?

*Bosentan* Pt has *Pulmonary HTN* -*plexiform lesions*=> lesions that form interlacing tufts of small vascular channels -maybe familial (*especially female*) #903

In a normal individual w/ high dietary K+ intake, what best describes the amount of K+ in the tubular fluid as it flows along the nephron in comparison to the filered K+ load?

*Bowman's Capsule 100%; PCT 35%; Thick Ascending limb of LoH 10%; CD 110%* K+ is freely filtered by glomerular membrane and depends on GFR. About 2/3 K+ is reabsorbed by PCT. Thick ascending limb go LoH reabsorbed 25-30% of K+. Alpha intercalated cells of DCT and CD modulate K+ via H+/K+ ATPases. #1554

The intracellular signaling found w/ Sildenafil is most similar to what substance produced normally by the body?

*Brain Natriuretic Peptide* *ANP and BNP* both bind TM receptors that are linked to *guanylyl cyclase* to increase cGMP. The increased cGMP induces activation of *protein kinase* to induce *vasodilation*. Nitric oxide is also similar! Penile erection is generated by ACh and NO release from parasympathetic fibers, leading to rise in cGMP and vasodilation of arteries to corpus cavernous. *Phosphodiesterase inhibitors* (Sildenafil) decrease degradation of cGMP, enhancing parasympathetics in erectile tissues. #1118

32yo female c/o pain and mass in the R flank. Imaging: large mass arising from R kidney and several smaller masses in L kidney. Histo: mass is composed of fat, smooth muscle, and blood vessels. Pt probable has what additional finding?

*Brain hamartomas and ash-leaf spots* *Renal Angiomyolipomas* are benign tumors of blood vessels, smooth m., and fat. *Angiomyolipomas* are associated w/ *Tuberous Sclerosis*, an *AD* (chr 17) disorder characterized by cortical tubers and *subependymal hamartomas* w/ consequent seizures and cognitive disability. Other things: mitral regurgitation, cardiac rhabdomyomas, facial angiofibromas, and *ash-leaf spots* #6

54 yo male w/ c/o 1wk of progressive HAs and confusion. He was treated for viral esophagitis 6mos ago and PCP pneumonia 2mos ago. Vitals: 100.4F, BP 142/86, and HR 64. Pt is lethargic. Head CT: mildly increased ventricular size. LP: increased opening pressure and CSF has increased protein and pleocytosis. Latex agglutination +. LM of CSF would show what?

*Budding Yeast* Pt's PMH is suggestive of *AIDS*. *Latex agglutination +* is indicative of *Cryptococcus neoformans* meningioencaphalitis. This organism will be *budding yeast* on LM. Can be cultured on *Sabouraud agar*. Tx w/ *Amp B* #118

Pt has NADPH oxidase deficiency. What infection is he at increased risk of receiving?

*Burkholderia cepacia* Pt has *Chronic Granulomatous Disease* characterized by *recurrent bacterial and fungal infections* due to *impaired intracellular killing* by phagocytes due to a defect in *NADPH oxidase*. NADPH transfers electrons to O2 to generate *reactive oxygen species*, such as H2O2 and OH-. *Catalase + organisms* can destroy their own H2O2 and will increase risk of infection. Common cat+ organisms: *Staphylococcus aureus, Serretia marcescens, B. cepacia, Nocardia sp., and Aspergillus sp.* #1441

73 nulliparous female c/o difficulty breathing. Increased abdominal girth, decreased appetite, and constipation for 6 mos. PMH--. PE: abdomen distended and nontender w/ R. adnexal mass. Surgical biopsy shows anaplasia of epithelial cells w/ invasion into stroma and multiple papillary formations w/ cellular atypia. What is most likely increased in this pt?

*CA-125* Pt has *Ovarian Cancer* and *epithelial subtype* is most associated w/ *increased CA-125* -*CA-125* is good for: *epithelial reproductive tract* and *peritoneum* #1837

2yo male c/o persistent diarrhea. Was healthy until 6mos old and has had 4 episodes of otitis media and 3 episodes of pneumococcal pneumonia. Was 50th percentile for wt and ht at birth but its not 25th % for ht and 10th % for wt. Diagnosed w/ Giardia lamblia infection. Workup shows very low serum levels of all Ig types. Flow cytometry shows deficiency of cells w/ what marker?

*CD 19* Recurrent sinopulmonary infections, failure to thrive, Giardia infection, and decreased Its makes this *X-Linked Agammaglobulinemia*, which is due to a mutation in *Bruton Tyrosine Kinase* causing failure of BM *pre-B cells (CD 19 and 20)* to develop into *mature B cells (CD 19, 20, and 21)*. Pan hypogammaglobulinemia (IgG, M, and A). Increased risk of *pyogenic (encapsulate) bacterial infections*. #1763

Russian immigrant w/ hx of wt loss, night sweats, and cough. Lung biopsy shows granulomas w/ central caseous necrosis. Surrounding necrosis are large cells w/ abundant pale cytoplasm. What serum marker is specific for these cells?

*CD14* Pt has *TB* and described cels are *macrophages*. *CD14* applies to the *monocytic-macrophage lineage* #1598

Inhibiting AA to PGs

*COX inhibitors*

What drug for psoriasis activates a nuclear transcription factor?

*Calcipotriene* *Topical Vitamin D analogs* (Calcipotriene, Calcitriol, and Tacalcitol) *bind and activate Vitamin D R.*, and nuclear TF that causes *inhibition of keratinocyte proliferation and stimulation of keratinocyte differentiation* #8569

30 yo WM w/ adult polycystic kidney disease comes to ER w/ severe HA and confusion. Neurologic PE: no meningeal signs or focal neurologic deficits. CT shows SAH. On fifth day of hospitalization, he c/o weakness in R arm and leg. What drug could have prevented his sequelae?

*Calcium Channel Blocker* Pts w/ *Adult Polycystic Kidney Disease* are at increased risk of *Berry Aneurysm*, that is at increased risk of rupture during *hypertensive episodes*. Once they rupture, they cause *Subarachnoid Hemorrhage*. Sequelae from a SAH can be prevented w/ the use of a specific CCB, *Nimodipine* #146

What crystals form w/ Pseudogout?

*Calcium Pyrophosphate* *Pseudogout* is almost clinically indistinguishable from gout. Synovial fluid analysis: increased WBC count and *rhomboid-shaped calcium pyrophosphate crystals*. + birefringent #1451

12 yo female w/ recurrent episodes of colicky abdominal pain and n. lasting several ds. Was recently hospitalized for an episode of difficulty breathing. No significant PMH, but mother has hx of severe abdominal pain and diarrhea. PE is normal. Labs show decreased C4 and C1 esterase inhibitor levels. What drug is contraindicated?

*Captopril* Pt has *Hereditary Angioedema*, and *AD disorder* that causes episodes of painless non pitting edema--neck, face, lips, and tongue are most commonly affected, but may involve internal organs (GI sxs) *C1 Esterase Inhibitor* suppresses C1 activation and also *inactivates kallikrein*, which *catalyzes kininogen -> bradykinin* -Bradykinin, C3a, and C5a mediate angioedema by increasing vasodilation and vascular permeability -Labs: increased bradykinin, C3a, C5a; decreased C4 and C1 esterase inhibitor -since *ACE inhibitors* also *create bradykinin*, they're contraindicated b/c of increased edema #1612

What enzyme makes it to where the Cl- content of RBCs is much lower in arterial blood than in venous blood?

*Carbonic Anhydrase* *Hb* carries *15% of CO2 as carbamate* and the *remainder of CO2 is carried as HCO3-*. CO2 is converted to carbamate (H2CO3) via *carbonic anhydrase* an carbamate spontaneously converts to *HCO3- and H+*. HCO3- tends to diffuse out of RBCs into plasma. In order to *maintain electrical neutrality Cl- ions take their place*, thus there is decreased Cl- in venous blood (but more Cl- in RBCs) #1414

15 yo female w/ gait instability. Since 12yo, she's had mild weakness and "clumsiness" in lower limbs that's progressed. She has to hold railing to walk. PE: kyphoscoliosis, pos cavus, and bilateral lower extremity ataxia. Joint position and vibration senses are impaired. She has an inherited disorder. What is she at the greatest risk of dying from?

*Cardiomyopathy* Pt has *Friedreich Ataxia*, an *AR disorder* associated w/ progressive *gait ataxia* (destruction of spinocerebellar tracts) and *impaired joint and vibration sense* (destruction of dorsal columns and DRG). May involve lateral corticospinal tract and cause +Babinski. May have findings of: skeletal abnormalities, *HCM*, and DM. Common cause of death: *Cardiomyopathy* arrhythmia and CHF) #636

55 yo male w/ COPD is evaluated for long-term oxygen therapy. His RR decreases shortly after beginning nasal annular oxygen supplementation. Pt's decreased RR is most likely due to stimulation of what sensory R.?

*Carotid Bodies* Pts w/ *COPD* develop a *decreased RR* when exposed to supplemental O2 b/c pts w/ long-standing COPD have *decreased sensitivity to PaO2*. The rapid increase in PaO2 w/ supplemental O2 can *decrease peripheral chemoreceptor stimulation* (carotid body and sinus) and *decrease RR*. -these sense PaO2 and H+ concentration #1583

Pt w/ CHF has bibasilar lung crackles and bilateral 1+ pitting edema of lower extremities. Echocardiogram shows biventricular dilation and a LV EF of 35%. Pt is -- for inducible ischemia. Long term tx w/ what will improve survival in this pt?

*Carvedilol* Pt has *Decompensated Systolic HF* due to nonischemic cardiomyopathy. After initial stabilization, *B-blockers* (Carvedilol or Metoprolol) increase survival in HF pts b/c of LV systolic dysfx. -decreases myocardial work and O2 demand by slowing ventricular rate and decreasing contractility -also decreases TPR -others that increase survival in systolic HF: *ACEi, ARB, and Aldosterone Antagonists* #1944

48 yo male w/ acute R knee pain. PME: PUD and GERD. R knee is swollen, erythematous, and tender. Athrocentesis: needle-shaped, negatively birefringent crystals w/ many PMNs. The treatment given selectively binds to an IL-1 inducible enzyme that is highly expressed on inflammatory cells and undetectable in surrounding tissues. What is the tx?

*Celecoxib* *COX-2* is an *inducible enzyme* that is undetectable in most tissues under normal conditions. During *inflammation*, macrophages secrete *IL-1 and TNF-a* that cause COX-2 upregulation to increase renal perfusion, vasodilation, tissue repair, increase pain sensitivity, and inflammation #7792

58 yo male w/ unrescectable hepatocellular cancer is scheduled for percutaneous embolization of the artery supplying the tumor. Contrast administered to which artery would enhance imaging of cancer?

*Celiac Trunk* This gives of Splenic A., L Gastric A., and *Common Hepatic Artery*. *Common Hepatic Artery* further divides into Gastroduodenal A, R Gastric A, and *Proper Hepatic Artery* #11760

75 yo male dies in MVA. No PMH, no meds, in good health, and his previous EKG showed no abnormalities. Autopsy shows heavy calcifications on aortic valve. What most likely preceded the aortic valvular changes seen?

*Cell necrosis* Pt has *dystrophic calcification*, affecting the aortic value. This is a hallmark of *cell injury and death* in all types of necrosis in the setting of *normal Ca+2 levels*. -may see Psammoma bodies -effects secondary to *chronic hemodynamic stress* -starts as aortic sclerosis -> aortic stenosis #296

62 yo female w/ long-standing T2DM experiences progressive renal decline for 4-5yrs despite BP control. She's started on hemodialysis and received a deceased renal allograft. 3wks later, she has generalized malaise. PMH: diabetic retinopathy and osteoporosis. Meds: Tacrolimus and Mycophenolate. Labs: K+ 5.2 (high), BUN 45 (high), Cr 3.1 (high), glucose 123 (normal), and Ca+2 10.0 (normal). Kidney biopsy shows lymphocytic infiltrate. What is the cause of pt's condition?

*Cell-medited immunity* Pt is in *Acute Rejection* (<6mos). Sxs tend to be fever, malaise, chills, and arthralgia. This can be humor or cell-mediated. *Cell-mediated* is characterized by lymphocytic interstitial infiltrate and necrotizing vasculitis. *Humoral-mediated* is characterized by C4d deposition, PMN infiltrate, and necrotizing vasculitis #11064

46yo homeless male w/ hx of alcoholism c/o frequent falls for 2-3wks. He "feels unsteady" and c/o occasional blurry vision. Drugs --. PE: coarse, rhythmic postural tremor affecting fingers and arms. This pathology is associated w/ damage to what brain structure?

*Cerebellum* Pt has *Alcoholic Cerebellar Degeneration* due to B1 deficiency and direct EtOH-related neurotoxicity. It is specifically due to loss of *Purkinjie cells* w/in *cerebellar vermis*. Pt may also have wide-based gait ataxia and trunchal instability #6810

21 yo male w/ c/o lesion on his penis. He noted a painful ulcer on L. side of his penis 4d ago and has increased in size since. No dysuria, hematuria, or penile discharge. He is HIV+ and sexually active. No meds. He appears comfortable and afebrile. PE: 1.5 cm ulceration on the R side of the base of the penis; this lesion is soft and very tender; has irregular borders; and is covered by grey exudate. There is a palpable inguinal LN of R. groin. PCR for herpes -- and dark field microcopy --. Dx?

*Chancroid* *Chancroid* is caused by *Haemophilus ducreyi*; a G-- that grows in a clumping pattern #11927

44 yo alcoholic male hospitalized for acute cholecystitis. 2d after admission, he becomes anxious, tremulous, and agitated. No other medical problems. What is the most appropriate tx for this pt?

*Chlordiazepoxide* *Chronic Alcoholism* causes *decreased GABA sensitivity*. Barbs and Benzos have similar GABA activity as EtOH. *Benzodiazepines* are used to *first line tx* for psychomotor agitation associated w/ EtOH withdrawal and to *prevent progression to seizures and delirium*. Long-acting Benzos (Diazepam and Chlordiazepoxide) are preferred. W/ liver disease, use of lorazepam, oxazepam, or temazepam b/c they don't have active metabolites and do not undergo oxidative metabolism. #350

65 yo male undergoing rehab for stroke still c/o muscle weakness and increased tone in the L. upper and lower extremities. Diazepam is used to decrease muscle spasticity or extremities. What other medication should he avoid?

*Chlorpheniramine* *Benzos* (Diazepam) are used for: *anti-anxiety, sleep, anticonvulsant, and muscle relaxation* (here for UPN disorder). Benzo's most common SE is *sedation* so you should always avoid coadministration of these drugs: *EtOH, Barbituates, neuroleptics, and 1st generation antihistamines* (Diphenhydramine, Promethazine, and Hydroxyzine) -other SEs: impaired coordination and balance, decreased memory, and confusion #352

73 yo male c/o unstable angina. He undergoes coronary angio via femoral approach. Stent is placed in R coronary A. and discharged. 2d later, he c/o a blue R toe. He has mild pain and tingling of affected toe. PMH: coronary A disease and hyperlipidemia. PE: apparent cyanotic toe and there is livedo reticularis affecting the R thigh. Peripheral pulses in lower extremities are bilaterally palpable. Preop serum Cr 1.0 but post-op Serum Cr 2.8. What histopathologic findings are seen on kidney biopsy?

*Cholesterol clefts in arterial lumen* Signs of embolism *blue toe, livedo reticularis* w/ normal peripheral pulse) following an invasive procedure is suspicious of *atheroembolic disease*. This caused ischemia and *Acute Kidney Injury*. Will not see flank pain or hematuria here b/c *cholesterol emboli* are too small. They leave *needle-shaped clefts* that obstruct arcuate and intralobular arteries. #810

56 yo male w/ persistent HTN. PMH:--. Fam hx: father had stroke at 60yo. Vitals: BP 152/95 and HR 75. Labs: Na+ 140 (norm), K+ 4.0 (norm), Cr 0.8 (norm), and fasting glucose 102 (norm). Pt is stared on low-dose Chlorthalidone monotherapy. Serum level of what is most likely increased?

*Cholesterol* *Thiazides* (Chlorthalidone) decrease BP by decreasing blood volume, decreasing CO, and decreasing systemic vascular resistance. They *inhibit Na+/Cl- co-transporters* in DCT. Its more potent than HCTZ in decreasing BP but is more associated w/ *metabolic abnormalities*: -*Hyperglycemia and Hypercholesterolemia*: decreased insulin secretion and increased insulin resistance-> increased *LDL cholesterol* -*HypoNa+*: inhibition of Na+/Cl- channel -*HypoK+*: compensatory increased renin and aldosterone -*HyperCa+2*: increased resorption in distal tubule -*Hyperuricemia*: increased resorption in PCT #2002

What tx for hyperlipidemia as a monotherapy would actually increase TGs?

*Cholestyramine* *Bile acid-binding resins* (Cholestyramine) work by binding intestinal bile acid and *inhibiting enterohepatic circulation*. This causes hepatic increase bile acid synthesis, increased uptake of LDL, decreased serum LDL, and increased hepatic synthesis of TG and VLDLs #163

45yo male c/o 1wk hx of purulent nasal discharge, HA, sore throat, and non-productive cough. PMH: -- except for Mononucleosis at 22yo. Smokes 1ppd. 100.4F. PE: maxillary sinus tenderness, pharyngeal erythema, and tender anterior cervical LAD. Labs: WBCs 58,000 (high), PMNs 42%, Myelocyes 30%, Metemyelocytes 8%, Bands 1%, Blasts 1%, Eosinophils 6% (high), Basophils 4% (high), and decreased leukocyte alk phos. Dx?

*Chronic Myelogenous Leukemia* DDX should be *CML* (uncontrolled mature granulocyte proliferation, mostly PMNs but also Basophils and Eosinphils) and Leukemoid Reaction. Both cause *increased WBC count and increased precursor forms*, but CML has *decreased leukocyte alk phos*. This is a *t(9;22)* at *BCR-ABL*. Tx is a *tyrosine kinase inhibitor* #1569

32 yo female w/ progressive SOB. Arterial blood labs: PaO2 normal; %sat normal; 02 content LOW. Most likely cause of results?

*Chronic blood loss* Total O2 content in blood is defined by the amount of Hb and SaO2. -here it is the lower Hb concentration

64 yo AA female has had several falling episodes in the past 6 mos. She gave up driving 1 yr ago b/c of multiple near-miss MVAs. PMH: HTN and T2DM. Normal MSE and Neurologic exam. Ophthalmic exam shows decreased vision in periphery and increased intraocular P. Pt is started on Timolol drops. What structure doe this target?

*Ciliary Epithelium* Pt has typical features of *Open-Angle Glaucoma* (chronic, progressive loss of peripheral vision) characterized by *atrophy of optic N. head* -common w/ advancing age and AAs -*Timolol*, and other non-specific B-blockers, fx to decrease aqueous humor production by the ciliary epithelium to *decrease intraocular P.* #1363

What component of terminal bronchioles would clear dust particles?

*Ciliated Cells* *Terminal Bronchioles* are ciliated cuboidal epithelium w/ Club cells -alveolar macrophages don't appear until RR bronchioles (next level) #1548

68 yo female w/ thigh and leg pain worse w/ exertion. PMH: HTN and DM. Smokes 2ppd and consumes EtOH occasionally. PE: weak dorsals pedis pulses bilaterally. Dx w/ moderate Peripheral A. Disease bilateral lower extremities. Which drug would provide symptomatic relief b/c of direct dilation of As. and inhibit platelet aggregation?

*Cilostazol* *Cilostazol decreased platelet activation* by *inhibiting platelet phosphodiesterase*, which is responsible for cAMP degradation and is a *direct vasodilation* -ultimately increased cAMP #1080

78 yo female is hospitalized for 2d of n/v, abdominal pain, and HA. Hx of COPD and she takes Theophyline. Was hospitalized for stroke, which was complicated by UTI and delirium. Pt appears restless and agitated. Vitals: 98.6F, BP 110/70, HR 118, and RR 22. PE: fine hand tremor. RR: mild expiratory wheeze. Serum Theophyline is increased. Tx w/ what agent caused her current sxs?

*Ciprofloxacin* *Cipro for her UTI* induced *Theophyline toxicity*. Theophylie is an *adenosine R. antagonist and phosphodiesterase inhibitor* for asthma and COPD. Bronchodilation via cAMP increases -theophyline is *metabolized by hepatic cytochromes* (inhibited by Cipro) -low therapeutic index: seizures, tremor, insomnia, GI disturbance, tachycardia, and arrhythmias #11752

Drug of choice for Gardnerella vaginalis?

*Clindamycin* -can also use Metronidazole #1958

41 yo male c/o fever, wt loss, and productive cough. HE drinks 12-18 beers/d. PE shows poor dentition. Foul-smelling sputum. CT shows air fluid levels/abscess in lungs. What antibiotic is most appropriate?

*Clindamycin* Pt has *Aspiration Pneumonia* caused by *Streptococcus pneumoniae*, associated w/ *alcoholism* -*Clindamycin* has the most activity against *oral anaerobes* and covers most G+ (works by inhibiting 50S rRNA) -note: abscesses are typically *polymicrobial* #1446

56 yo male w/ hx of HTN and hyperlipidemia w/ c/o chest pain, diaphoresis, and light headedness. His sxs started 1hr ago while stacking boxes. Pain described as tight squeezing sensation in center of chest and radiates down L. arm. EKG: STEMI in leads I, III, and aVF. The tissues affected by this pt's acute condition undergo what histologic changes over the next few days?

*Coagulative Necrosis* *Coagulative Necrosis* develops after an *irreversible ischemic injury*in more tissues (except brain). *Tissue architecture is preserved* after cell death due to denaturation of lytic enzymes and disrupted proteolysis. Cells become *anucleated* w/ eosinophilic cytoplasm*. #178

69yo female c/o R foot weakness following hip replacement. She was in R lateral decubitus position for entire surgery. PE: unable to dorsiflex or evert R ankle or extend toes. Sensation is decreased over dorsum of foot. What nerve is injured?

*Common Peroneal Nerve* *Common Peroneal N.* is the lateral branch of the sciatic nerve and further divides into superficial and deep perineal Ns. Common perineal N. is susceptible to injury at the *lateral neck of the fibula* (i.e. laying on side, a cast, or crossed legs) or *proximal fibular fracture*. Presents w/ *foot drop* from damage to *deep peroneal N.* and *loss of dorsal foot sensation* from damage to *superficial peroneal n.* #1149

34 yo male gets in MVA and has considerable trauma. He's hypotensive w/ several bleeding sites. Has splenic laceration and receives emergency blood transfusion. En route to OR, he develops difficulty breathing, chills, and pain in chest and back. Urine drainage is now brown in color. What is the most likely cause of pt's new findings?

*Complement-mediated cell lysis* Pt is experiencing an *Acute Hemolytic Transfusion Reaction*. Occurs minutes-hours after blood transfusion, primarily due to *ABO Incompatibility* This is a *Type II Hypersensitivity* mediated by IgG and IgM and C' activation -may progress to DIC #747

27 yo female finds incidental raised, pigmented lesion on leg. No itching or pain. Admits to tanning bed use. Fam hx: father died of skin cancer. PE: <6mm diameter w/ a symmetric, demarcated border. Biopsy: uniform round cells at basal potion of epidermis into dermis. Inconspicuous nuclei w/o mitotic activity. Dx?

*Compound Melanocytic Nevus* #11502

54 yo female c/o difficulty hearing for past few wks. Tuning fork his heard bone>air on L. side and Weber test lateralizes to L. ear. What type of hearing loss does she have?

*Conductive heading loss in left ear* *Conductive hearing loss*: BC>AC in *affected ear*, AC>BC in unaffected ear, and Weber *lateralizes to affected ear*. #8589

Researchers are assessing the association btwn colorectal CA and NSAID use. They first interview pts w/ colorectal CA and then they interview a group of the pt's neighbors of similar age and ethnicity. Analysis is based on comparing pairs of individuals who have similar characteristics. This helps address what bias?

*Confounding Bias* *Matching* helps control *counfounding* (a perceived association btwn an exposure and outcome is actually explained by a founding variable associated w/ exposure and outcome). It ensured *similar distribution* #1189

21-Hydroxylase Deficiency

*Congenital adrenal hypoplasia* (most common form) -neonates w/ virilization -life-threatening hyponatremia (salt-wasting)

Mitral Valve Prolapse is closely related to abnormality in what tissue?

*Connective Tissue* *Primary MVP* is characterized by myxomatous degeneration (i.e. pathologic *deterioration of CT*) affecting the leaflets and chord tendineae--this is what *secondary MVP* is associated w/ Ehlers-Danlos Syndrome and Osteogenesis Imperfecta -murmur disappears w/ squatting #947

Which of the following will most likely decrease Renal Plasma Flow and Increase Filtration Fraction?

*Constriction of efferent arteriole* Efferent constriction *decreases RPF*; increased glomerular capillary hydrostatic pressure (b/c fluid blacks up)--b/c GCHP increased, *filtration fraction increases* *FF=GFR/RPF*; RPF directly proportional to PAH *GFR=Kf[(Pg-Pb)-(pig-pib)]* #1618

56 yo male for checkup. PMH: HTN, T2DM, Hyperlipidemia, and mild intermittent asthma. No meds. Reports feeling we.. Vitals: BP 152/101 and HR 87. Waist circumference 43 in. Labs: increased LDL, Glucose, and HbA1C. What vascular bed will have the most atherosclerosis?

*Coronary Arteries* The most susceptible regions of atherosclerosis are at *bends and branches* b/c of high turbulence and local flow distribution. Thus, *lower abdominal aorta and coronary As.* are most susceptible--there are even fatty streaks in the second decade of life here! #11636

Administration of certain drugs in ischemic myocardium causes a redistribution of blood away from ischemic areas, exacerbating myocardial ischemia. This phenomenon is b/c of what mechanism?

*Coronary Arteriolar Dilation* In ischemic cardiomyopathy, collateral circulation develops to provide O2 to the ischemic areas. *Adenosine and Dipyridamole* are *selective coronary vasodilators* and cause redistribution of blood flow through the collateral microvessels and coronary arterioles that can decrease collateral blood flow. This is known as *Coronary Steal* #952

What vessel has the greatest difference in blood O2 content compared to the Aorta?

*Coronary Sinus* Most cardiac venous blood drains into the RA via *Coronary Sinus*. Things to note: *LV is only perfused during diastole* b/c coronary vessels are blocked during systole. Subendocardium most susceptible to ischemia *Myocardial O2 extraction is very high*; the extraction is higher than any other tissue, making it the most de-O2 blood in the body *Myocardial O2 demand and coronary blood flow are tightly coupled*; mediated by Adenosine and NO -the answer isn't "Pulmonary Artery" b/c it contains coronary sinus blood and blood from systemic venous circulation #2009

If the nerve deep to the mucosa overlying the piriform recess is damaged, what is impaired in the pt?

*Cough Reflex* The *Piriform Recess* contains the *Internal Laryngeal Nerve*, a branch of the superior laryngeal nerve (CN X). This only carries sensory and autonomic fibers and mediates the *afferent limb of the cough reflex* #8703

21 yo male c/o SOB, fatigues, myalgia, and debilitating retroorbital HAs for several ds. He's been working on a dairy farm for 3wks. He cleans out animal waste, but does not handle hay. PHM --. No tobacco. Abd. --. CXR: R lower and middle lobe consolidation. CBC: normal Hb, decreased platelets, and normal leukocytes. LFTs: increased AST and ALT. HIV--. Most likely causative agent?

*Coxiella burnetti* Pt has *Q fever* due to *inhalation from air contaminated by animal waste* -may also have photophobia -lobar consolidation is very common -Labs are + for abnormal LFTs and Thrombocytopenia #11859

42 yo male c/o SOB and fatigue for 2wks. No chills but has recent wt gain and ankle swelling. PMH--. Vitals: BP 162/93 and HR 95. PE: bilateral lower extremity pitting edema. Urinalysis: 2+ protein, WBC 5-7, and RBC 75-100. IF of kidney biopsy shows linear deposits. What would be seen on LM?

*Crescent Formation* Pt has *Nephritic Syndrome* due to *Anti-Glomerular Basement Membrane Disease*. Abs target *Type 4 Collagen* of GBM, activating C' deposition -*LM*: *Glomerular Crescents* of proliferating parietal cells and monocytes infiltrate -*IF*: *linear deposition* of *IgG and C3* -Abs may crossreact w/ pulmonary tissue and induce *Pulmonary Hemorrhage* (hemoptysis)--combined w/ renal sxs=*Goodpasture Syndrome* #9

35 yo male received a kidney transplant 1yr ago and comes to ER w/ c/o pleuritic chest pain and cough. Has low-grade fever. CXR: infiltrate in lower L lobe. Pt started on broad spectrum antibiotics w/o resolve. BAL conducted and mucicarmine stain shows red cells. Dx?

*Cryptococcus neoformans* *Cryptococcus neoformans* has a lot of different stains. *Methenamine silver* stains the yeast form as *round cells w/ narrow-based buds*. *India Ink* fails to stain the capsule so its presents as a *halo*. *Mucicarmine* stains it *red* While meningoencephalitis is more common, C. neoformans may also cause *Cryptococcal Lung Disease* and presents as pneumonia-like disease: pleuritic chest pain, dyspnea, and hemoptysis #117

34 yo industry worker experiences rapid-onset SOB, dizziness, palpitations, and flushed skin after accidental exposure to chemical fumes. Pt has reddish discoloration of skin w/o cyanosis. He's instructed to inhale Amyl Nitrate. This antidote works by converting Hb into a form w/ increased affinity for what substance?

*Cyanide* Pt has *Cyanide Toxicity*, which is dependent on its ability to bind *ferric iron (Fe+3)* w/ high affinity, inhibiting *cytochrome c oxidase* and disrupting oxidative phosphorylation. Labs: *severe lactic acidosis and narrowing of venous-arterial PO2 gradient*. Administration of *Amyl Nitrate* oxidizes ferrous iron (Fe+2) to Fe+3, generating *methemoglobin*. Methemoglobin cannot bind O2 but binds CN tightly and sequesters from blood -note: Hydroxycobalamin and Sodium Thiosulfate are also antidote but they increase renal excretion #1415

What agar is specific for Corynebacterium diphtheriae?

*Cysteine-Tellurite Agar* -G+ cat+ aerobic club-shaped #1095

34 yo male w/ severe Crohn's disease is found to have a small bowel obstruction. The severely inflamed portion is removed and genetic analysis shows a gene mutation resulting in decreased activity of NF-kB pathway. This pt's mutation will most likely impair what process?

*Cytokine Production* *IBD* (Crohn's and Ulcerative Colitis) likely involves abnormal response to intestinal micro biome in genetically predisposed individuals. *NOD2 gene* is highly assoc. w/ *Crohn's disease*. *NOD2* is expressed on epithelial cells and macrophages to regulate *innate immunity*. It encodes an intracellular R. to recognize LPS and *activate NF-kB*, which is a pro inflammatory TF that *increases cytokine production*. There is decreased expression in Crohn's. #135

34 yo male presents w/ fever, myalgias, malaise, and progressive fatigue for 2wks. No sore throat. He received a blood transfusion for gastric ulcer. PE: mild splenomegaly. No LAD or jaundice. Lymphocytosis w/ 30% atypical lymphocytes. Pt's serum failed to agglutinate horse RBCs. HIV--. What caused pt's condition?

*Cytomegalovirus* *CMV* causes heterophile Ab-- *mononucleosis-like-syndrome* #1593

Cell line is infected w/ a virus isolated from a 45 yo male. Viral progeny have a phospholipid component highly similar to cell nuclear membrane. Pt is infected w/ what?

*Cytomegalovirus* *Herpesviridae* (CMV) bud out of nucleus #1408

53 yo male w/ c/o frequent HAs and dizziness. PMH: HTN and PUD. Meds: Chlorthalidone and Antacids. Vitals: 98.6F, BP 146/92, HR 89, and RR 16. BMI 26. PE: facial plethora and splenomegaly. Labs: Hb 21.5 (high), Hct 64% (high), RBCs 7.6 (high), platelets (high), and WBCs (high). Pt has a mutation in what type of protein?

*Cytoplasmic Tyrosine Kinase* Pt has *Polycythemia Vera* due to a mutation in *Jak kinase 2*, a *cytoplamsic (non-receptor) tyrosine kinase*. This causes activation and clonal proliferation of myeloid cells. Increases risk of PUD and gouty arthritis. #8591

67 yo male w/ c/o fatigue and low-grade fever. No hx of heart disease. Vitals: 101.1F, BP 117/76, HR 82, and RR 14. PE: diastolic murmur at L sternal border. HE has nontender erythematous macule on hands and feet. Blood cultures: G+ cocci cat-- and grows in hypertonic (6.5%) saline and bile. PMH will show what previous procedure?

*Cytoscopy* Pt has *Enterococcal Endocarditis* from *Lancefield Group D Enterococci* (Enterococcus faecalis and Enterococcus francium) -gamma hemolytic -cat-- -PYR + -saline and bile + -*flora*: urinary and GI -increased antibiotic resistance (B-lactam and Aminoglycoside for tx) #733

Clostridium difficile's toxin damages what compartment of intestinal mucosa?

*Cytoskeleton Integrity* *C. diff* has two toxins: *Toxin A (enterotoxin) and Toxin B (cytotoxin)*. Both toxins *inactivate Rho-regulatory proteins* involved in signal transduction and *actin cytoskeletal structure*. This then *disrupts intercellular tight junctions*, leading to watery diarrhea #1397

19 yo male college student w/ ulcer on his penis. Lesion for 3ds. PE shows indurated and painless ulcer near glans of penis w/ no erythema or inguinal LAD. 1st line tx has structural similarities to what?

*D-Ala-D-Ala* Pt has *Syphilis* and is tx w/ *Penicillin G*. -they work by binding *transpeptidases* that *crosslink peptidoglycan cell walls* #1952

8 yo male w/ hx of recurrent RR infections and is being evaluated for neurological sxs. Pt's gait is unsteady w/ spontaneous loss of balance. Parents are concerned about language development. Pt's eyes won't "move smoothly" when looking at moving objects. PE: numerous superficial blanching nests of capillaries on sun-exposed areas. The genetic defect in this child most likely plays a role in:

*DNA Break Repair* Pt has *Ataxia Telangiectasia*, an *AR* disorder w/ mutation in *ATM gene*, responsible for DNA break repair -*triad*: cerebral ataxia, telangiectasia, and increased risk of sinopulmonary infections -primarily *IgA deficiency* #587

What is the normal fx of BRCA 1/2?

*DNA Repair* -TSG important in familial breast and ovarian cancer -repairs dsDNA breaks -AD w/ variable penetrance #1083

6mo female in for well child visit. Mom is concerned about baby's growth despite adequate feeding. PE: hepatomegaly, hypotonia, and ht and wt are below 10th percentile. Labs: hypoglycemia and ketoacidosis. Liver biopsy: hepatic fibrosis w/o fat accumulation. There are abundant quantities of multi branched polysaccharides w/ abnormally short outer chains w/in cytosol. What enzyme is deficient?

*Debranching Enzyme* *Cori Disease's* key distinguishing feature is the *cytosolic accumulation of abnormally short outer chains* #1030

55 yo male is aout to get surgical repair on his rotator cuff muscles. Immediately before surgery, he receives anesthesia w/ an injection btwn the R anterior and middle scalene muscles for blockade of brachial plexus. Which muscles is likely to be paralyzed?

*Diaphragm* *Brachial Plexus* (C5-T1) passes btwn the anterior and middle scalene muscles in the posterior triangle. *Interscalene nerve block* causes transient ipsilateral *diaphragmatic paralysis* b/c of the *phrenic nerve* (C3-C5) #11744

Researchers infuse healthy volunteers w/ a pure adrenergic agonist that causes increased systolic and diastolic blood pressure but decreases HR. What other physiologic change happened?

*Decreased AV node conduction velocity* Pts were injected w/ *selective a1 agonists* (Phenylephrine or Methoxamine), causing *vasoconstriction* (increased BP) and *stimulation of Baroreceptors* on carotid sinus and body caused *reflexive increased vagal influence* (decreasing pacemaker activity/decreasing HR/decreasing myocardial contractility) -increased pulmonary capillary wedge pressure (increased LA pressure) -increased afterload #1343

How would the cardiac hemodynamics of a pt with acute mitral regurgitation due to spontaneous rupture of chordae tendineae compare to a normal heart? (afterload, preload, and left ventricular ejection fraction)

*Decreased Afterload; Increased Preload; Increased Left Ventricular Ejection Fraction* B/c LV must accommodate regurgitated blood and normal pulmonary venous blood, there's *increased LV EDV (increased preload)*. The incompetent mitral valve causes regurgitation and that *decreases LV afterload*. Increased preload w/ decreased afterload (per Frank-Starling) ultimately causes *increased LV EF*. Note: Stroke volume decreases, leading to *hypoTN* and cariogenic shock #11851

33 yo male c/o worsening dyspnea. He used to be a frequent jogger but not gets short of breath while walking dog. PMH--. Smokes 1ppd. BMI 27. Cardiac exam normal. Labs: decreased serum a-1 antitrypsin. What PFTs would most likely be present? (FEV1/FVC, TLC, and DLCO)

*Decreased FEV1/FVC; increased TLC; decreased Diffusing capacity of Carbon Monoxide* Pts w/ *AAT Deficiency* develop early-onset *emphysema*. These 3 changes in PFTs are b/c of destruction of alveoli and ajoining capillary beds. #1919

38 yo male w/ c/o dyspnea on exertion and decreased exercise tolerance. PMH--. Never smoked and no occupational exposures. Pt has gained almost 100 lb in 4yrs and is in a new sedentary lifestyle. Currently weighs 297.6 lb and BMI 41. Vitals: RR 22 and Pulse Ox 93%. PE: central obesity. Lungs clear bilaterally. What changes to FEV1, FVC, ERV, RV, and TLC would be seen on this pt's PFTs?

*Decreased FEV1; decreased FVC; decreased ERV; normal RV; decreased TLC* P that *Obesity-Related Restrictive Lung Disease*. Obesity causes *decreased chest wall compliance* (b/c of increased wt) and *decreased lung compliance* (b/c of microatelectasis). To compensate for decreased compliance, obese people increase RR and thus they have *decreased tidal volume* (rapid-shallow breaths). #11900

Pt binge drinks. Liber biopsy shows hepatic steatosis. What caused the fatty change in pt's liver?

*Decreased FFA oxidation* *Alcohol-induced hepatic steatosis* is due to decreased FFA secondary to *increased NADH production* from the alcohol metabolism enzymes -also will see impaired lipoprotein assembly #370

46 yo female gets radical hysterectomy and R. ureter is damaged. Studies show partial obstruction of R. ureter w/ mild dilation of proximal collecting system. What changes are seen w/ R. kidney?

*Decreased GFR and Filtration Fraction* *GFR* is dependent on hydrostatic and oncotic pressure -*increases w/*: increased glomerular hydrostatic P. -*decreases w/*: increased capsular hydrostatic P. or increased capillary oncotic P. #1651

72 yo female evaluated for fatigue and SOB on exertion for 1mo. Pt c/o lower back pain but no cough or fever. PMH: HTN and Valsartan. Vitals: 99F, BP 130/80, HR 84, and RR 14. PE: conjunctivae area pale. CBC: Hb 8.2 (low), Cr 2.1 (high), Ca+2 11.2 (high), total protein 8.5, and Albumin 3.7. X-ray of lower back shows lucency in L4 and L5 vertebrae. Serum protein electrophoresis shows a monoclonal gamma globulin spike. Labs show? (PTH, Urine Ca+2, Vitamin D, and PTH-rp)

*Decreased PTH; Increased urinary Ca+2; Decreased Vitamin D; Normal PTH-rp* Pt has *Multiple Myeloma*. *HyperCa+2* from *osteolysis*, which then *inhibit PTH* release. Low PTH causes decreased Vitamin D #12101

43 yo female recently dx w/ hypothyroidism has Labs: increased TSH; decreased T3 and T4. After administration of T3 to this pt, what change in hormone levels occur?

*Decreased TSH; increased T3; decreased Reverse T3; and decreased T4* Pt has *Primary Hypothyroidism*, as seen by her initial lab values. *HPT axis* is regulated by *--feedback by T3* on TRH. *Exogenous T3* decreases TSH, which then *decreases T4 secretion* by thyroid. Further, *rT3 decreases* b/c of decreased available T4 for conversion to T3. -*Reverse T3* is an inactive form that is generated by peripheral conversion of T4 #1615

What cellular changes would be seen with low dose Atenolol? (cardiomyocyte [cAMP], JG cell [cAMP], vascular smooth muscle [cAMP])

*Decreased cardiomyocyte [cAMP]; decreased JC cell [cAMP]; no change vascular smooth muscle [cAMP]* *Atenolol* is a *selective B1 antagonist* and B1 Rs are found on *cardiac tissue and JG cells*, but not vascular smooth muscle. *B1 blockade* will cause *decreased Gs* stimulation, thus *decreasing cAMP levels* #8289

64 yo male /o acute-onset pain, n, and v. Pt had small bowel resection due to bowel ischemia 1yr ago and has been on TPN since. PMH: A-fib and HTN. PE: RUQ pain on deep palpation. Labs: moderate leukocytosis w/ normal hepatic transaminase, amylase, and lipase. Abdominal US: gallstones and edema of gallbladder wall. No hx of gallstones. What is the reason for gallstone development?

*Decreased cholecystokinin release due to lack of enteral stimulation* Pt has *Cholesterol Gallstones* due to *decreased CCK release* and subsequent *biliary stasis*. That CCK was not released b/c there was no fat or amino acid sensing from small intestine. #77

43 yo female is started on a new medication for T2DM. The new drug activates peroxisome-proliferator activated receptor-gamma, a nuclear receptor and transcription facto. Activation of this receptor would result in what?

*Decreased insulin resistance* *Thiazolidinediones* (Pioglitazone) decreases insulin resistance by binding PPAR-gamma, which binds other coactivataors. Important genes unregulated include: *GLUT-4 and Adiponectin* *GLUT-4*=> insulin-dependent glucose transporter on skeletal muscle and adipose *Adiponectin*=> adipose cytokine to increase insulin-sensative adipocytes and stimulates FA oxidation Overall effects: decreased insulin resistance, increase adiponectin production, increase FA oxidation, decrease TNF-a production, and decrease leptin production #920

23 yo male gets in MVA and was unrestrained. Several ds after hospitalization, his plasma volume and plasma osmolarity are measured. There is symmetric decrease in ECF and ICF volumes and symmetric increase in their osmolarities. What condition cause this?

*Diabetes Insipidus* Pt has *Central DI* from head trauma in MVA disruption hypothalamus/pituitary, decreasing ADH. This caused excessive free water excretion by kidneys, causing *hyperosmotic volume contraction*. The is when *loss of free water is greater than loss of electrolytes*. -can occur in: *DI, dehydration, or profuse sweating* #1379

87 yo nursing home resident brought to ER b/c of 2d hx of fever, vomiting, and progressive lethargy. PMH: dementia and stroke. Vitals: 101F, BP 88/62, and HR 120. PE: coarse rhonchi over R lower lung. Labs: leukocytes 23,000 (high), platelets 210,000, Na+ 140, K+ 4.2, Cl- 101, HCO3- 18 (low), Cr 0.9, Glucose 121, and lactic acid 4.0 (high). What caused this pt's anion gap?

*Decreased oxidative phosphorylation* Pt is in *septic shock* and has *anion gap metabolic acidosis* from *lactic acidosis*. *End-organ hypo perfusion* in septic shock impair tissue oxygenation and *decreases oxidative phosphorylation* (increased NADPH and shunting of pyruvate-> lactate) #2101

32 yo male started on Infliximab for refractory Crohn's. 10d later, he develops joint pain and pruritic risk. Skin biopsy shows fibrinoid necrosis and PMN infiltrate of small blood vessels. What accompanied this pt's condition?

*Decreased serum C3 level* Pt has *Acute Serum Sickness* due to *tissue deposition of circulating immune complexes (Type III Hypersensitivity)*. Starts 7-14d after Ag exposure. May also see LAD and proteinuria. *Deposition of IgM and/or IgG* causes C' activation and *hypocomplementemia* -highly associated *w/ chimeric mAbs* (Rituximab and Infliximab), *non-human Igs* (venom antitoxin), and *nonprotein drugs* (penicillin, cefaclor, and TMP-SMX) #741

12 yo male w/ c/o fatigue. PE--. Urinalysis: protein +1, trace blood, RBC 20-30, and RBC casts. LM of kidney biopsy shows enlarged, hypercellular glomeruli. What additional finding is most likely seen?

*Decreased serum C3 level* Pt has *PSGN* Labs: increased anti-streptococcal Abs (streptolysin O, DNase B, or cationic proteinase) and decreased C3 concentration; maybe cryoglobulin+ LM: as above EM: electron dense deposits ("humps") on epithelial side of BM IF: coarse granular deposits of IgG and C3 w/ *"starry sky"* appearance #12

54 yo male w/ restrictive cardiomyopathy progresses to acute decompensated HF. He's started on Digoxin and reports symptomatic relief. What initial intracellular event is happening b/c of Digoxin?

*Decreased sodium efflux from myocardial cells* *Digoxin* is a *positive ionotropic agent* for acute decompensated HF due to LV dysfx. It also *increases parasympathetic tone* and *slows conduction through AV node*. It works by directly *inhibiting Na+/K+-ATPase pump*, leading to *decreased Na+ efflux* and increased intracellular Na+. The increased intracellular Na+ decreases the activity of the *Na+/Ca+2 exchanger*, causing secondary *decrease in Ca+2 efflux*. Increased intracellular Ca+2-> increased binding of Ca+2 to Troponin C-> increased actin-myosin binding-> *improve myocyte contractility* and LV systolic fx #148

42 yo male c/o exertion dyspnea and fatigue. His sxs have progressively worsened for 2wks and cannot walk across a room. He dies despite aggressive tx. Autopsy of his heart shows a dilated LV. His sxs are cause by what mechanism?

*Decreased ventricular contraction force* -pt has systolic dyxfx #92

What is the MOA of the drug used to treat Status Epilepticus?

*Decreases sodium current in cortical neurons* *Phenytoin* is a long-term anticonvulsant used to prevent frequency of *Status Epilepticus* by inhibiting neuronal high-frequency firing in the cortex via reducing the ability of *Na+ channels* to recover from inactivation -note: *Benzos* (lorazepam) is used for *immediate control* of status epileptics and works by *increasing GABA effect* by increasing postsynaptic Cl- influx -other note: Phenytoin and Benzos are often used concurrently! #353

24 yo mountain climber falls on R. arm and heard a snap. There's extensive bruising over lateral R. arm w/ inability to extend arm. Xray shows mid shaft fracture of humerus. What artery is injured?

*Deep Brachial Artery* *Deep Brachial A. and Radial N.* (C5-T1) could be damaged -Deep brachial A. passes inferior to teres major and courses along w/ Radial A. #1704

20 yo male c/o intermittent episodes of self-resolving jaundice. Sxs are not provoked. Pt feels otherwise healthy. CBC is normal. LFTs: normal total protein and albumin; increased total bilirubin and direct bilirubin; normal Alkaline Phosphatase, ALT, and AST. Liver biopsy: abundant pigment inclusions in the lysosomes of otherwise normal hepatocytes. Pigment is composed of polymers of Epinephrine metabolites. Most likely cause of pt's jaundice?

*Defective hepatocellular excretion of bilirubin glucuronides* Pt has *Dubin-Johnson Syndrome*, and *AR disorder* where there's a mutation in the canalicular membrane transport protein. -pts are asymptomatic and only have episodic jaundice -liver is grossly black from decreased epinephrine metabolite excretion -direct/conjugated hyperbilirubinemia #101

34 yo male w/ progressive lower back pain. Stiffness gets better throughout day. HLA-B27 Ag+. Xray shows fusion of sacroiliac joints. What is most helpful to monitor disease progression?

*Degree of chest expansion* Pt has *Ankylosing Spondylitis* *Enthesitis*: inflammation at site of inception of tendon to bone *RR*: involvement of costovertebral and costosternal junctions can limit chest wall expansion, leading to hypoventilation. *Cardio*: ascending aortitis may lead to dilation of aortic ring and aortic insufficiency *Eye*: *anterior uveitis*--pain, blurred vision, photophobia, and conjunctival erythema. #753

34yo male c/o weakness, dizziness, and paresthesias involving face and extremities after eating pufferfish. Neurologic PE: decreased muscle strength and deep tendon reflexes. What part of action potential is impaired?

*Depolarization* *Tetrodotoxin* (pufferfish) and Saxitoxin ("red tide") *bind v-gated Na+ channels*, preventing Na+ influx and depolarization COD: hypoTN and RR failure #8352

26 yo female w/ hx of childhood dermatitis, asthma, and hay fever has been routinely applying corticosteroid cream to flexor areas for yrs. A punch biopsy of these areas would likely show what?

*Dermal Atrophy* Extended use of topical corticosteroids will decrease production of extracellular matrix collagen and GAGs and consequences include dermal atrophy, telengiectasias, and atrophic striae. #1214

5 yo male presents w/ cyanosis on minimal exertion. Cyanotic episodes are increasing in frequency. During episodes, pt squats and it makes him feel better. PE: prominent R ventricular impulse and harsh systolic murmur. What is the mechanism of this pt's condition?

*Deviation of infundibular septum* The clinical presentation (*cyanotic episodes* that improves w/ *squatting*, prominent ventricular impulse, and *systolic murmur*) is consistent w/ *Tetrology of Fallot*. *Abnormal neural crest cell migration* leads to *deviation of infundibular septum*, resulting in *VSD and overriding aorta*. The *cyanosis* occurs b/c of *RVOT obstruction*, which also causes *RV hypertrophy*. Squatting increases systemic vascular resistance (increased afterload) and decreases R->L shunt, decreasing cyanotic episode #1705

52 yo male w/ c/o 2wk hx of progressive fatigue and exertion dyspnea. No chest pain or palpitations. Cardiac auscultation of murmur best heard when he sits up and leans forwards. Murmur is best heard where on Wigger's Diagram?

*Dicrotic notch as LV starts to decrease in pressure* Pt has *Aortic Regurgitation*. This graph actually *lacks a dicrotic notch, steep diastolic decline in aortic P., and high LV and aortic systolic peaks*. -has a *decrescendo diastolic murmur* best heard sitting up and leaning forward w/ breath held at end-expiration #227

Pulse w/ 2 distinct peaks

*Dicrotic pulse* in pts w/ severe systolic dysfx and high system vascular resistance.

54 yo male c/o abdominal pain, chronic diarrhea, and recent wt loss. Abdominal pain worse after eating. Pt consumes alcohol regularly. Abdominal Xray: calcifications in epigastric area. What is likely cause of diarrhea?

*Digestive Enzyme Deficiency* Pt has *Chronic Pancreatitis* and the calcifications are due to ductal plugs. *Malabsorption and diarrhea* are due to *exocrine deficiency*. #1547

43 yo female w/ c/o occasionally chest pain over 1yr. Described as midline pressure or squeezing that lasts 10-15 min and is sometimes w/ diaphoresis. No hx of HTN or DM, but is a smoker. Exercise stress test is good w/o signs of ischemia. Ambulatory EKG shows transient STEMI in leads I, aVL, and V1-V4 during chest pain at night. Which tx would provoke pt's chest pain?

*Dihydroergotamine* Pt has *Variant (Prinzmetal) Angina*, char by spontaneous episodes *at rest or nighttime andgina* associated w/ *transient STEMI*. -caused by *transient, sudden, and significant decrease in luminal diameter* of a coronary A. due to spasm -*Dihydroergotamine* txs acute migraine HA; induces variant angina by constriction of smooth muscle b/c of *partial a and serotonin agonism* (others: cigarettes, amphetamines, and triptans) -tx w/ *Amlodipine* #38

65yo male c/o sudden onset HA. No head trauma. PMH: HTN and lung adendoCA w/ metastasis. Initial had CT: small temporal hemorrhage. Over 24hrs, he's progressively obtained and develops generalized tonic-clonic seizures. Vitals: BP 160/96, HR 38, and RR 6 w/ brief episodes of apnea. Repeat CT: acute hematoma expansion w/ brain herniation. What is found on repeat neurologic exam?

*Dilated Pupil* Pt's *Cushing Triad* (HTN, bradycardia, and bradypnea) likely *increased ICP.* The lesion and increased ICP induced *Uncal Herniation*, compressing *ipsilateral CN III* and have a *fixed dilated pupil* due to damage of preganglionic parasympathetic fibers. #11804

28 yo female G3P3 presents w/ severe abdominal pain in LLQ and vaginal bleeding. Saturating pads every 3-4 hrs. LMP 6 wks ago. Surghx of 3 Csections and bilateral tubal ligation. Urine pregnancy test +. US shows 2cm adnexal mass addicted to ovary and a thickened endometrial stripe. If a uterine curettage is performed, what would be present?

*Dilated, coiled endometrial glands and edematous stroma* Pt has an *Ectopic Pregnancy* -most common site is *ampulla* -Path: *decidualized endometrium* consistent w/ above --due to progesterone --will lack embryonic and trophoblastic tissue #324

Elderly pt experienced a syncopal episode and c/o recent-onset severe constipation. PMH: HTN, COPD, and A-fib. Vitals: BP 105/60 and HR 50. EKG: new-onset 2nd degree AV block. What drug caused this?

*Diltiazem* *Nondihydropyridine CCBs* (Diltiazem, Verapamil) are *L-type CCBs* that decrease phase 0 depolarization and conduction velocity of pacemaker cells. They "act on the heart." They *slow sinus rate* and AV node conduction, causing bradycardia and varying AV blocks. -they have *-- ionotropic effects* that make them contraindicated in CHF due to LV dysfx -*constipation* is a major SE -note: dihydropyridine CCBs are known to "act on vascular smooth m." 3153

45 yo male c/o epigastric abdominal pain and fatigue. Has had similar sxs in past. Vitals normal. PE: midepigastric tenderness and hepatomegaly. No jaundice or LAD. Labs: decreased Hb; increased MCV; and normal platelets and WBCs. Abdominal CT shows pancreatic calcification. RUQ US is -- for gallstones. What is responsible for pt's anemia?

*Diminished Thymidine Synthesis* Pt has *Chronic Pancreatitis*due to EtOH abuse. *Hepatomegaly* from EtOH-induced hepatic steatosis. *Macrocytic anemia* from *folate/B12 deficiency* (most likely folate). -*megaloblastosis* from deficient DNA synthesis b/c folic acid is responsible for purine and pyrimidine (thymidine) synthesis #1580

What is the MOA of Pramipexole?

*Directly stimulates dopamine receptors* *Dopamine Agonists* do not have to be metabolized to be active. There are 2 classes: 1) Ergot: *Bromocriptine* 2) Non-ergot: *Pramipexole and Ropinirole* Dopamine agonists have a *long half-life* and can *delay the need to start Levodopa* thereby postponing motor fluctuations -note: Bromocriptine is also used to tx hyperprolactinemia #703

62 yo male w/ hx of acute MI 2yrs ago and long hx of HTN. Doc decides to increase dose of diuretic. At f/u, labs show increased serum Ca+2. Diuretic acts where on nephron?

*Distal Convoluted Tubule* *Thiazides* work at *DCT* by *increasing Na+, Cl-, and water excretion* by acting on the early DCT *Na+/Cl- supporter*. Decreased intracellular Na+ causes increased activity in *basolateral Na+/Ca+2 exchanger*, causing decreased intracellular Ca+2-> increased luminal absorption of Ca+2 in DCT. Increased Ca+2 reabsorption by *PCT* is what causes the *increased serum Ca+2* w/ thiazides. -SEs: hypoK+, hypoNa+, hypoMg+2, and hyperCa+2 #683

After 12hrs of water deprivation, where in the nephron would most likely be measured at 110 mOsm/L?

*Distal Convoluted Tubule* Tubular fluid osmolarity in setting of *high ADH*: *PCT*: 300 mOsm/L (isotonic) *Descending limb of LoH*: >300 mOsm/L and may get to 1,200 (hypertonic) *Thin ascending limb of LoH*: <300 mOsm/L (hypotonic) *DCT*: about 100 mOsm/L *CD*: up to 1,200 mOsm/L #1608

Additional tx blocking what Rs. would be helpful in chemo-induced emesis?

*Dopamine, Serotonin, and Neurokinin 1* *Nucleus Tractus Solitarus* found in medulla coordinates vomiting and is stimulated by: M1, D2, H1, 5-HT3, and NK1 Rs. #11728

External beam radiotherapy decreases a tumor's size via what mechanism?

*Double-stranded DNA breaks* *Ionizing Radiation* (gamma rays and x-rays) induce cell death via 2 mechs: 1) *dsDNA breakage*--requires damage to both strands 2) *Free Radial Formation*-- damage to cell and DNA #1474

Pt complains of diplopia and difficulty focusing eyes. No PMH. Shining light into R eye causes constriction of R pupil, but NOT L pupil. Shining light into L eye causes constriction of only the R pupil. What would also be found on PE?

*Drooping of L eyelid* Pt has *L. CN III Palsy* -loss of somatics for: inferior, superior, and medial rectus, inferior oblique (down and out gaze), and lavatory palpebrae (ptosis) ms. -loss of parasympathetics for: innervation of iris sphincter and ciliary m. (fixed, dilated pupil w/o accommodation) Pretectal nucleus->EW Nucleus->CN III->Ciliary ganglion->eye #8557

Pt presents w/ progressive dyspnea, dizziness, and chest discomfort. No PMH other than URI 2 wks ago. Fam hx of MI. EKG shows pericardial fluid accumulation w/ later diastolic collapse of R atrium. What PE will be seen in this pt?

*Drop is pulse amplitude during inspiration* Pt has *pericardial effusion assoc. w/ cardiac tamponade* *Beck's triad*: HTN, JVD, and muffled heart sounds. EKG findings: b/c of displacement of pericardial fluid w/ ventricular expansion. #1782

3 alpha agonists are assessed for vasoconstrictive activities. Drug #1 is furtherest to the L. on drug concentration but peaks/levels off 1/2 way before the other 2. Drugs 2 and 3 have tall, sigmoidal curves, except Drug #3 is further R. than Drug #2. What is the best statement concerning the effects of these drugs? (x-axis = drug concentration and y-axis is effect)

*Drug 2 has higher affinity for alpha-receptors than Drug 3* *Efficacy* is the intrinsic ability of a drug to elicit and effect. It is the measure of the *maximum ceiling of activity [Emax]*. This is measured by the *y-axis*. *Potency* is the dose of the drug that is required to produce a given effect. Potency is primarily affected by the *affinity of a drug for its receptor and amount of drug that is able to reach target tissues.* Higher affinity = greater potency. A lower ED50 = lower potency. This is measured by the *x-axis*. -Drugs 2 and 3 have similar efficacy, but Drug 2's potency > Drug 3's potency #1707

50 yo G0P0 female w/ no fam hx of cancer has microcalcifications found on routine mammogram. Histology of breast biopsy: ducts distended by pleomorphic cells w/ prominent central necrosis. Lesion does not extend beyond BM. What is the most likely origin?

*Duct* Pt has *Ductal Carcinoma In Situ* and it arises from breast ducts. It is the precursor to the most common type of breast cancer, *invasive ductal CA*. Age and nulliparity are risk factors; whereas, breastfeeding is protective. Spread of these malignant cells to the nipple results in eczematous nipple changes and indicates *Paget's disease*. #1057

Researchers notice that colonization of the gastric Antrum w/ Helicobacter pylori is associated w/ decreased number of somatostatin-producing Antrum cells. Depletion of these cells from the Antrum will most likely cause what?

*Duodenal Ulcers* Somatostatin normally decreases gastrin release, thus increasing gastric pH. W/o delta cells, the gastric pH decreases and the duodenum receives highly acidic contents, inducing *duodenal ulcers* -not associated w/ malignancy -answer would have been "gastric ulcer" if H. pylori was present in the gastric body (corpus) #1603

4 yo WF w/ abdominal pain has a blind pouch connected to ileum. Pouch is removed and has pancreatic acini in mucosa. The latter finding is described as?

*Ectopy* Pt has a *Meckel Diverticulum* due to incomplete obliteration of *omphalomeseneteric duct* that connects midgut to yolk sac -most commonly has gastric tissue though -presents as acute appendicitis -*Ectopy*=> functional and microscopically normal cells in wrong location #321

Anthrax Exotoxin MOA

*Edema factor*: increases cAMP concentration by acting as an adenylate cyclase, causing edema and phagocyte dysfx *Lethal factor*: a zinc-dependent protease that inhibits mitogen-activated protein kinase signaling, causing apoptosis and multisystem physiologic disruption

7yo previously healthy male c/o swelling of hands and feet. 2wks ago, he was treated for anaphylaxis form a bee sting. In the past 10ds, he's had progressive hand and feet swelling, increased "tightness" of his pants. Urine is "frothy". PE: periorbital edema, pitting edema of hands and feet, and mild ascites. Lungs clear. Lipids mildly increased. Urinalysis: protein 4+, hyaline casts, and everything else --. What is abnormal in this pt?

*Electron microscopy of a glomerular filtration unit* *Minimal Change Disease* is the most common nephrotic syndrome in *children* and tends to follow URTI, immunization, or insect bite. Systemic T cell dysfx induces *selective albuminuria* b/c of loss of -- charge of GBM. LM and IF --. *EM: effacement of podocytes* -tx: *corticosteroids* #384

5 yo male develops HUS 4d after eating hamburgers at a family picnic. Vitals normal. PE: pallor. He has no peripheral edema or rashes. Labs: anemia, thrombocytopenia, and increased BUN and Cr. What other lab would be seen?

*Elevated serum indirect bilirubin* *HUS* causes intravascular hemolysis, causing decreased Hb and haptoglobin and increased LDH and indirect bilirubin #1857

Why does the Peds Hib vaccine contain both the capsular polysaccharide of Hib and conjugated tetanus toxins if a kid already has DTaP?

*Elicits T cell dependent immune response* *Polysaccharide capsule elicits a B cell IR*. However, polysaccharide vaccines are ineffective in children <2yo b/c of immature humoral immunity. B/c of this, the *capsule is conjugated to a carrier protein* to amplify the humoral response via T cell recruitment. #965

Atypical endometrial cells, disorganized glands, and multiple mitoses

*Endometrial CA* -primarily postmenopausal women w/ vaginal bleeding

30 yo nulliparous female w/ c/o infertility. Trying to conceive for 2 yrs. Menarche at 11 yo w/ menses 2-3 times/yr that lasts 7-10d. Vitals: BP 128/84, HR 84, and BMI 35. PE: acne and hair growth on upper lip and chin. Pt is at greatest risk for what?

*Endometrial Carcinoma* Pt has *Polycystic Ovarian Syndrome* and has a classic *triad* of hirsutism, irregular menses, and/or polycystic ovaries -increased androgens prevents follicular maturation (anovulatory)=>oligomenorrhea/no pregnancy *Decreases progesterone secretion* => *long-term risk of endometrial hyperplasia and endometrial CA* #258

Child w/ facial skin lesions for 2d. Afebrile. Lesions are tender perioral papule and pustules; some have broken down and are covered in golden yellow crusts. Micro: G+ cocci in chains. Which component of the clinical syndrome most likely follows infection?

*Facial puffiness and dark urine* Pt has *impetigo* caused primarily by S. aureus and secondarily by *S. pyogenes*. He is at highest risk for *PSGN* char by: facial edema, HTN, hematuria, nephrotic proteinuria, and urinary RBC casts. Immune complex deposition. #725

62 yo female c/o several mo hx of tingling and numbness in her feet. She also has a small ulcer on her R foot that doesn't seem to be healing. PMH: long-standing diabetes, HTN, and gout. PE: decreased pain sensation over both feet and bilateral absent ankle reflexes. Pt's neurologic sxs are associated w/ what?

*Endoneural arteriole hyalinization* *Nonenzymatic glycosylation* of proteins leads to increased thickness, hyalinization, and narrowing of walls of arteries. Ischemic nerve damage follows. *Intracellular Hyperglycemia* occurs in peripheral nerves. Glucose is covered into sorbitol and fructose by aldose reductase. *Sorbitol* increases cell osmolarity and facilitates water influx. Osmotic damage to axons and Schwann cells #1059

24 yo female in ER for L leg swelling and pain for 2d. Pt is 14 wks pregnant and it has been uneventful. Does not c/o SOB or chest pain. PMH--. Nonsmoker. PE: 1+ edema of L lower extremity to knee, associated w/ mild erythema. US shows popliteal and femoral vein thrombosis. Serum Cr 0.7. What is the best treatment option?

*Enoxaparin* Pregnancy increases risk of venous thromboembolic disease. *LMWHs* (enoxaparin) provides the best balance btwn safety for mother and fetus. They *do not cross the placenta*, have simple administration, good bioavailability, and short half-life #1194

Vibrio cholerae toxin

*Enterotoxin*: permanently activates Gs, increasing cAMP levels -osmotic diarrhea (rice water)

35 yo male has lab studies that show high titers of IgG directed against Hepatitis C envelope protein. What is the most likely reason these Abs don't confer effective immunity to infection?

*Envelope proteins have variations in their antigenic structure* *Hep C Virus* has multiple subtypes b/c of its *RNA-Dep-RNA-Poly* has no *proofreading 3'->5' exonuclease*, increasing mutation rate. Further, the strains differ primarily at *hypervariable genomic regions*, such as those found on *envelope glycoproteins* #44

26 yo female w/ newly dx seizure disorder presents w/ fever and skin rash. She was stared on Phenytoin 6wks ago. Temperature 102F. There is a diffuse confluent erythema involving 60% of her body, palpable generalized LAD, and symmetrical facial swelling. What lab finding is present?

*Eosinophilia* *DRESS Syndrome* (Drug Reaction w/ Eosinophilia and Systemic Sxs) is associated w/ *anticonvulsants* (phenytoin and carbamazepine) *Allopurinol*, Sulfonamides, and antibiotics (minocycline and vancomycin). Maybe associated w/ drug-induced herpes reactivation. Sxs: *fever, generalized LAD, and diffuse morbilliform skin rash*. Labs: *eosinophilia*, lymphocytosis, and increased ALA. #508

61yo male has Wernicke-Korsakoff Syndrome. The pt's brain findings are most likely associated w/ a decrease in what?

*Erythrocyte transketolase activity* *Thiamine (B1)* is a cofactor for the following enzymes: -*Pyruvate Dehydrogenase* -*a-ketoglutarate dehydrogenase* -*branched chain a-ketoacid dehydrogenase* (breakdown Ile, Leu, and Val) -*transketolase* (pentose phosphate pathway to convert ribulose 5-P to Glyceraldehyde 3-P) -answer is not "glutathione reductase" b/c that's not measured in B1 deficiency #598

57 yo WM hospitalized for muscle pain, fatigue, and dark urine. PMH: stable angina. Meds: Atorvastatin, Metoprolol, and Aspirin. Labs reveal he's in acute renal failure. Addition of which medication most likely precipitated this pt's condition?

*Erythromycin* *Rhabdomyolysis* is a rare SE of *statin use*. W/ the exception of *Pravastatin*, they're all metabolized by *c-P450 3A4*, which is *inhibited by Erythromycin*, thus increasing serum concentration of *Atorvastatin* -alternate use would have been *Azithromycin*, since its a macrolide w/o cup inhibition #161

Pt w/ PCOS wants to increase fertility w/ a drug. What is the tx?

*Estrogen Receptor Modulator* *Clomiphene* is an ERM that *prevents negative feedback inhibition* on hypothalamus and pituitary by estrogen, causing increased FSH and LH and ovulation #2095

49yo G2P2 c/o 10mos of irregular vaginal bleeding. Her LMP was 3yrs ago. PMH: hypothyroidism on Levothyroxine. US: thickened endometrium and solid L adnexal mass. Endometrial Biopsy: abnormal. Ovarian mass is yellow and firm. Path: small cuboidal cells in sheets w/ gland-like structures containing acidophilic material. Cells are arranged in a microfollicular pattern around a pink, eosinophilic center. What is secreted from this tumor?

*Estrogen* *Granulosa Cell Tumors* tend to present as *postmenopausal bleeding*. They're *"sex cord-stomal tumors"*, which contain granulose and theca cells. Granulosa cells form rosettes (*Call-Exner Bodies*) that's gland-like and have *coffee bean nuclei*. Theca cells give the yellow color b/c of lipid content. They tend to be *unilateral* masses that *secrete estrogen* and induce *endometrial hyperplasia*. Labs: increased estrogen and inhibin -pts are at increased risk of endometrial CA #1158

Calculate Excretion Rate

*Excretion Rate = Filtration Rate - Tubular Reabsorption Rate*

13 month old male comes for f/u for undescended R testicle. PE: absence of R. testis in scrotal sac w/ a round mass palpated superior to scrotum and medial to R. mid-inguinal point. During repositioning, the malpositioned testis will most likely be pulled through a physiologic opening in what?

*External abdominal oblique muscle aponeurosis* During normal testicular desertion, testes pass from abdomen through the *deep inguinal ring* to enter the inguinal canal, via a physiologic opening in the *transversalis fascia* (muscle is lateral and inferior epigastric vessels are medial). Testes then travel anteromedial out of canal via *superficial inguinal ring*, formed by *external abdominal oblique muscle aponeurosis*, and on to scrotum! #11762

4 wk old male born to primigravada has been breastfeeding really well and has had sufficient wet diapers. His urine is dark yellow and has had a few pale-colored stools. He's been slightly icteric for 2wks. PE: well-appearing w/ icteric sclerae and jaundice on head and upper chest. Abdominal exam: mildly enlarged and firm liver. LFTs: total bilirubin 7.3 and direct bilirubin 5.0 (both increased). What is the mechanism of pt presentation?

*Extrahepatic obstruction of bile ducts* *Biliary Atresia* is an *obstruction of extra hepatic bile ducts*. Biliary tree is normal at first but undergoes destruction via either immune or viral-mediated mechanisms. Its will present w/ *jaundice* w/in first 2mos of life, along w/ *dark urine and acholic* (pale) *stools* from increased renal excreted bile. Labs: *increased direct bilirubin and gamma-glutamyl transferase*. -liver biopsy: intrahepatic bile duct proliferation, portal tract edema, and fibrosis -cause of death: cirrhosis (needs surgery) #317

Calculate Filtration Rate

*FR = GFR x Plasma concentration*

14yo female c/o bump below her R breast. Bump has been there forever, but has become larger in past 2-3 yrs. It becomes tender before onset of menses. Menarche at 12yo w/ normal ovulatory cycle. Tanner stage 5. Both breasts and axillae seem normal. PE: soft, raised, hyperpigmented, 0.5 cm nontender lesion inferior to R breast. What is the cause of presentation?

*Failed involution of the mammary ridge* Pt has an *accessory nipple* due to the *failure of involution of the mammary ridge*. They're asymptomatic but may *swell or become tender* w/ menses. They can occur anywhere along the embryonic milk line (think pig tiddies). May see *hyperpigmenation and epidermal thickening* #8904

21 yo college athlete c/o fatigue and recent wt loss. He says that no matter how much he eats, he can't gain wt. He's also had increased thirst, drinking lots of water, and making frequent bathroom trips. He's sexually active with one lifetime partner. Fam hx: father diagnosed w/ colorectal cancer at 64yo. What study would help w/ dx?

*Fasting Glucose Level* Wt loss despite increased food intake, polydipsia, polyuria, and fatigue are suggestive o *T1DM*. Labs: *fasting glucose >126*, random glucose >200, and *increased HbA1C* -oral glucose tolerance test for GDM and CF-related DM #921

26 yo female w/ newly dx schizophrenia is started on Olanzapine. At her 3 mo check up, what studies should be obtained?

*Fasting glucose and lipid panel* 2nd generation antipsychotics are often used 1st line to avoid EPS. However, they tend to cause *metabolic adverse effects* (wt gain, dyslipidemia, increased glucose, and increased risk of DM). -*Olanzapine and Clozapine* are at greatest risk #11848

Elderly female presents w/ n/v and abdominal pain that began 6 hrs ago. C/o vague pelvic pain for a few months. Vitals: febrile, HTN, and tachycardic. PE: mild abdominal distention and tender bulge below inguinal ligament. What structure is immediately lateral to the bulge?

*Femoral V.* *Femoral hernias* occur *below* inguinal ligament and protrude through femoral ring. #417

Where on a damaged heart's valve would Viridans streptococci adhere?

*Fibrin-Platelet Aggregates* *Viridans streptococci* is a G+ cocci that's capable of producing extracellular polysaccharides (*dextrans*) using sucres. They're associated w/ *transient bacteremia* after *dental procedures*. Dextrans facilitate attachment to *fibrin and platelets*. #1003

Angiography of hepatic neoplasm shows a well-demarcated, highly vascularized tumor surrounded by normal liver parenchyma. What substance was likely contributing to neovascularization?

*Fibroblast Growth Factor* *Angiogenesis* is primarily mediated by 2 factors: 1)*VEGF*: angiogenesis and increases endothelial motility and proliferation 2)*FGF*: angiogenesis, embryogenesis (angioblast production), hematopoiesis, and would repair (macrophage recruitment) #1873

Biopsy of malignant melanoma shows that it has decreased integrin expression. B/c of this, it'll have decreased binding to what extracellular matrix component?

*Fibronectin* *Integrins* are transmembrane proteins that bind: *collagen, laminin, and fibronectin* #1872

54 yo male dies of profuse upper GI hemorrhage. Gross exam of liver shows a bright-red nodular liver. Condition resulted from what process?

*Fibrosis and nodular parenchymal regeneration* *Cirrhosis* is characterized by *diffuse hepatic fibrosis w/ replacement of normal nodular architecture w/ fibrous regenerative parenchymal nodules*. #368

7 yo male injured his R knee bicycling. Motor and sensory nerves intact. X-ray shows nondiplaced patellar fracture. Pt placed in cast. 1wk f/u and he c/o paresthesias and numbness at dorsal of R foot and weakness of dorsiflexion at R ankle. What is the site of nerve compression?

*Fibular Neck* *Common Peroneal Nerve* courses around the *fibular neck* and divides into deep and superficial branches. Pinching at *fibular neck* causes *foot drop, eversion, and impaired sensation on lateral shin and dorsal of foot* #1748

Stillborn born from a mother w/o prenatal vitamins. PE: several dysmorphic features including closely set eyes and a midline mass consistent w/ a proboscis. Autopsy: fused cerebral hemispheres w/ an absent forebrain fissure and a single intracranial ventricle. What is the most likely mechanism?

*Field Defect* Stillborn has *Holoprosencephaly* due to *incomplete division of the forebrain* (prosencephalon) into 2 hemispheres. Occurs at *5wks*. It's associated w/ Trisomy 13, Hedgehog gene mutation, and maternal EtOH abuse #252

Newborn has a Strawberry Hemangioma on L buttock. This vascular tumor will do what overtime?

*First increase in size and then regress* #466

Is Lung Cancer the first, second, or third in rate of mortality in females?

*First* *Mortality* in Females: Lung > Breast > Colon *Incidence* in Females: Breast > Lung> Colon #1823

56 yo female septic secondary to kidney/bladder infection. Vitals: 102.6F, BP 70/40, HR 130, and RR 28. CBC: leukocytosis w/ increased PMNs. Coagulation normal. Several hours later, she becomes hypoxic and requires mechanical ventilation. Her respiratory sxs are likely due to what pathologic finding?

*Fluid accumulation in the alveolar spaces* *Sepsis* and pulmonary infections are risk factors for *ARDS*. During sepsis, *TNF, IL-1, IL-6, and IL-8* circulate and activate pulmonary epithelium. This induces PMN extravasation into lung tissue, provoking an inflammatory response, and *fluid accumulation in alveolar spaces*. #1579

32yo female c/o progressive SOB. No chest pain or tobacco use. Vitals: 98F, BP 132/81, HR 102, and RR 30. Her condition rapidly deteriorates and she's intubated b/c of acute respiratory failure. She goes into cardiac arrest and dies. Medical records show numerous medications w/ poor compliance. Autopsy: hyper inflated lungs, airway mucous plugging, and cellular infiltrate into bronchial wall. Long-term use of what drug would have prevented the cellular reaction in the pt's airway?

*Fluticasone* PT has *Bronchial Asthma*, which is characterized by *chronic airway inflammation* and edema leading to *bronchial wall thickening and remodeling*. Airway is hyper responsive and there's increased risk of bronchoconstriction. *Glucocorticoids* have anti-inflammatory effects, decreasing airway obstruction by decreasing mucous production, and decreases WBC extravasation #169

16 yo male w/ mild intellectual disability evaluated for ADHD. He's noted to be impulsive and inattentive by parents and teachers. Poor grades. Hx of gross motor and speech delay. PE: long and narrow face, prominent mandible, and large testes. Hyperlaxity of finger and thumb joints. Most likely dx?

*Fragile X Syndrome* *FXS* is an X-linked disorder w/ a loss of fx mutation in *FMR1 gene* on long arm of X. #1808

23 yo apparently health male immigrated to America. PMH-- but he was told he "has a problem metabolizing sugar." He has absolutely no diet restrictions. Urine sample shows +Cu+2 reduction test and glucose oxidase dipstick --. What enzyme is deficient?

*Fructokinase* Pt has *Essential Fructosuria*, a benign *AR disorder* where you experience fructosuria due to inability to metabolize fructose. Fructose, as is glucose and galactose, is a *reducing sugar* and can be detected on a *Cu+2 reduction test*. -- glucose dipstick rules of presence of glucose in urine. #1067

Different monosaccharides have different rates of intracellular metabolism. What would have the fastest rate of metabolism in glycolytic pathway?

*Fructose-1-Phosphate* Look for monosaccharides that bypass their rate-limiting enzymes. F-1-P bypasses PFK-1 and can be converted by *Aldolase B* into *DHAP and Glyceraldehyde*. Aldolase B can use either F-1-P or F-1,6-BP as substrates #1068

Insulin infusion causes a drastic increase in what substance w/in the liver?

*Fructose-2,6-Bisphosphate* *Insulin* is often used in DKA pts to push cells towards *glycolysis* by *decreasing cAMP*, resulting in the *activation of PFK-2* to convert *F-6-P -> F-2,6-BP*. F-2,6-BP then *stimulates PFK-1* to convert *F-6-P -> F-1,6-BP* and ultimately pyruvate #6758

72 yo female c/o difficult hearing. She was admitted 1wk ago for dyspnea, orthopnea, and bilateral leg swelling, which has improved w/ tx. Her hearing was normal prior to hospitalization but has gotten worse in the past 2d. PMH: HTN, HF, and CKD. PE: bilateral sensorineural hearing loss. Which meds caused hearing loss in this pt?

*Furosemide* Pt w/ *pulmonary edema and peripheral edema* due to HF and CKD tx w/ diuretics, most like *loop diuretics* -they *inhibit Na+/K+/2Cl- symporters* in the *ascending limb of LoH* -they are also associated w/ *ototoxicity*--*especially in CKD pts* -additional SEs: hypoK+, hypoMg+2, and hypoCa+2 #685

An antiepileptic medication works by selectively blocking v-gated Ca+2 channels. This tx most likely affects what step of neurotransmission?

*Fusion and release of neurotransmitter vesicles* Once the axon hillock becomes sufficiently depolarized by Na+ influx, v-gated Na+ channels open for Na+ influx, and AP is propagated. This allows for *v-gated Ca+2 channels* to open and allow for *Ca+2 influx*, which is essential for *fusion and release of NTs* #11682

46 yo male has been acting strange for the last 6mos. He does not seem to care about his family anymore and sometimes becomes aggressive. He has periodic jerky movements of his arms. No fam hx b/c he's adopted. Deficiency of what NT causes these sxs?

*GABA* Pt has *Huntington's Disease*, an AD disorder that tends to present in 30-40yrs old. There's *atrophy of caudate nucleus and striatum* #902

11 yo female w/ c/o blurry vision. Adopted at 9yo. No hx of trauma or radiation. Achieved developmental milestones. Has good appetite w/o restriction. Up to date on vaccines. Vitals normal. 40th percentile for ht and wt. Normal PE, other than bilateral lens opacities. Urine + for reducing substances. What enzyme deficiency is causing this pt's eye condition?

*Galactokinase* Pt has *Galactosemia* and cannot convert *Galactose->Galactose-1-Phosphate* and a buildup of galactose is then *converted to Galactitol*, causing *cataracts* #1074

5d old newborn c/o multiple emesis. Breastfed infant has been having fewer. Wet diapers for past 2d. Vitals: tachycardia, tachypnea, and hypoTN. PE: icteric, lethargic baby w/ shrunken fontanelle, dry mucous membranes, and hepatomegaly. Cultures: G-rods. CBC: leukocytosis and bands. Labs: hypoglycemia, increased transaminases, and normal ammonia levels. Newborn placed on special formula and improves over next few ds. What reaction cannot be conducted?

*Galactose-1-Phosphate -> (w/ the conversion of UDP-Glucose to UDP-Galactose-> Glucose-Phosphate* Pt has a deficiency in *Galactose-1-Phosphate Uridyl Transferase (GALT)*, which catalyzes the above reaction. Lactose is converted into glucose and galactose and the galactose cannot be metabolized. This causes *Galactosemia*, which presents w/ *vomiting and lethargy* soon after *breastfeeding*. May have renal liver dysfx. Predisposes infant to *E. coli sepsis*. #1071

68 yo female comes in for check-up. Feels healthy and recently lost 9lb on diet and exercise. No hx of jaundice, abdominal pain, or changes in stool. PMH: HTN and hypercholesterolemia. PE: firm mass is palpated in RUQ. CT of abdomen shows thickened gallbladder wall w/ a rim of patchy calcification. Pt is at an increased risk of what?

*Gallbladder Adenocarcinoma* Pt has a *Porcelain Gallbladder*, typically an asymptomatic, palpable gallbladder w/ CT findings described in question -it's a potential manifestation of *chronic cholecystitis* #87

64yo male c/o 2d hx of dysuria, urinary frequency, and urgency. He underwent cystoscopy for hematuria. PMH: HTN, T2DM, and 30 pack hx. 100.8F. PE: suprapubic tenderness w/o CVAT. Urinalysis: leukocyte esterase +, nitrites --, bacteria +, WBCs +, and RBCs +. Urine culture: G+ cocci in chains. What biochemical characteristic does this microbe have?

*Gamma hemolysis on blood agar* The pt's *cystoscopy* increased his risk of *Enterococcus sp.* infection. G+, cat--, gamma hemolytic, bile +, salt +, and PYR + that grows in chains/pairs -they tend to be MDR #11812

46 yo female w/ persistent hyperlipidemia despite 6mos of healthy diet and exercise. PMH: biliary colic secondary to gallstones and refused cholecystectomy. Fam hx: father died of MI at 54yo and mother has DM. Vitals: 97F, BP 122/79, HR 78, and RR 14. PE: normal. Labs from 1wk ago: increased TGs and LDL. Given preexisting gallbladder disease, what tx should be avoided?

*Gemfibrozil* *Fibrates* (Gemfibrozil) work by inhibiting *Cholesterol 7-alpha hydroxylase*, the rate-limiting enzyme in bile acid synthesis. Decreased bile acid *decreased cholesterol solubility*, increasing precipitate formation, and *promoting gallstone formation*. Thus, vibrates are *contraindicated in preexisting gallbladder diseases* -statins, fish oil, an niacin are associated w/ *decreased gallstone risk* #164

3 yo female w/ developmental and speech delay does not imitate parent's actions, have a social smile, or show interest in other children. Lab shows 226 CGG trinucleotide repeat on X chromosome. What's the cause?

*Gene methylation* Pt has *Fragile X Syndrome*. This is the most common inherited intellectual disability. PE: macroorchidism and dysmorphic facies. Psych: ADHD and Autism Cause: *hypermethylation of FMR1* during meiosis in oocytes. CGG! #1421

4d old preme develops a decreased level of unconsciousness and hypotonia. She had normal pregnancy and delivery. Baby's birth wt was 1,200 g. PE: lethargic infant w/ a weak and high-pitched cry, prominent scalp veins, and tense fontanels. US: blood in lateral ventricles. What is the source of the bleed?

*Germinal Matrix* Pt has an *Intraventricular Hemorrhage*, which is associated w/ prematurity and birth wt <1,500 g. Tends to present w/in 5 d of life. These usually originate from *Germinal Matrix*, a highly vascularized layer in the sub ventricular zone that lacks supporting glial cells #8564

Pt c/o light headedness whenever he buttons a tight collard shirt. Even feints. Decreased BP w/ events. Stimulation of afferents from what nerve is responsible?

*Glossopharyngeal (CNIX)* Pt has *Carotid Sinus Hypersensitivity*. -*Afferent limb*: IX -*Efferent limb*: X (parasympathetic) #1609

What endogenous substance allows for serum insulin to be higher w/ oral glucose vs IV glucose infusion?

*Glucagon-like peptide-1* *Incretins* (GLP-1 and Gastric Inhibiting Peptide) are produced by gut mucosa and stimulate pancreatic insulin secretion. They're independent of plasma glucose levels #6803

Inhibiting conversion of Phospholipid to Arachidonic Acid

*Glucocorticoid* inhibit *Phospholipase A2*, decreasing the formation of LTs and PGs -given to gout pts that cannot take NSAIDs or Colchicine

24 yo female diagnosed w/ Gestational DM during her 1st pregnancy. Her blood glucose has remained increased since delivery. PMH:--. Fam hx: mother and sister had "high blood sugars" during pregnancy. If pt's gestational hyperglycemia is genetically predisposed, she is most likely to have decreased activity of what enzyme?

*Glucokinase* *Glucokinase* has a *lower glucose affinity* (high Km) than Hexokinase. B/c of its high Km, it acts as the *glucose sensor* in pancreatic B cells. Heterozygous mutations can decrease glucose metabolism-> decreased amount of ATP is produced-> result of decreased insulin produced. This produces a *maturity-onset diabetes of the young*, that worsens w/ pregnancy-induced insulin resistance. #1010

When a pt is in metabolic acidosis, what aa is metabolized to increase excretion of acid?

*Glutamine* Acidosis stimulates *renal ammoniagenesis*, where glutamine is metabolized into NH4+ (excreted) and HCO3- (reabsorbed) #11939

54 yo male w/ hx of cirrhosis found agitated and confused. He was nauseous and vomiting bright red blood several times yesterday. Cirrhosis is secondary to chronic Hepatitis C infection, and has received tx for esophageal varies in the past. PE: abdominal distention, decreased liver span, and testicular atrophy. A jerky, irregular flexion-extension tremor involving his hands is seen w/ wrist extension. what is increased in his astrocytes?

*Glutamine* Pt has *Hepatic Encephalopathy* b/ of recent GI bleed causing *increased nitrogen absorption in gut* (increased circulating *ammonia*). *Astrocytes* regulate the CNS environment and regulate neurotransmission by taking up *Glutamate* and undergoing a condensation reaction via *Glutamine Synthase and NH3* to generate *Glutamine*. *Excess NH3* w/in blood is taken up by astrocytes, *increasing Glutamine production*. Astrocytes will swell b/c of increased osmolarity. Ultimately, there's *disruption of excitatory neurotransmission*. #8578

Which diabetic drug will increase pt's C-peptide level?

*Glyburide* *Sulfonylureas* (Glyburide and Chlorpromide) cause *increase insulin release from pancreatic B cells* #1655

76 yo female w/ T2DM found unresponsive after having a busy day prior and not eating meals. She's on one oral medicatin for DM. Random glucose 44. Her condition rapidly improves after IV Dextrose, but she becomes confused several hrs later. Repeat glucose 49. What medication caused her condition?

*Glyburide* Persistent hypoglycemia is a common SE of *2nd generation Sulfonylureas* (Glyburide), which act by *binding and inhibiting ATP-dependent K+ channels* in pancreatic B cells. This causes a net insulin release that is *independent of glucose concentration*. 2nd generation Sulfonylureas have different duration times. *Glyburide and Glimepride* are long-acting and have increased incident of hypoglycemia; whereas, Glipizide is short-acting w/ decreased incidence. #11565

18 yo female w/ T1DM c/o several hrs of n/v and abdominal pain. Admits to not taking insulin for 2d. Labs: blood glucose 452 and high anion gap metabolic acidosis. Urinalysis: ketones+. Pt's insulin deficiency caused increased production of gluconeogenic precursors that are converted in liver to glucose. What enzyme provides these precursor substrates?

*Glycerol Kinase* Pt is in *DKA* and there is *increase triglyceride metabolism* via *hormone-sensitive lipase*. TGs yield FFAs (ketogenesis) and *glycerol*. Since adipocytes cannot metabolize glycerol, it travels to the liver and is phosphorylated by hepatic *glycerol kinase* into Glycerol-3-P. G-3-P is then converted to*DHAP* via *G-3-Dehydrogenase* and can now undergo gluconeogenesis. #1889

A Myastenia Gravis pt, on appropriate medication, begins to experience abdominal cramping, n/v, and sweating. What tx will control these sxs?

*Glycopyrrolate* Pt is on an *AChE inhibitor* but this may induce *muscarinic overstimulation* of smooth muscle cells and glands. *Selective muscarinic antagonists* (Glycopyrrolate, Hyoscyamine, and Propantheline) decrease SEs of AChEi while allowing them to be therapeutic bc they have *no activity at Nicotinic Receptors* (which is where MG pathology is located) #2062

Pt consumes excess amounts of food w/ sodium nitrite. Distal third of his esophageal cells have accelerated cytosine deamination of chromosomal DNA. Damage is most likely repaired through what enzymatic sequence?

*Glycosylase, Endonuclease, Lyase, Polymerase, and Ligase* *Dietary nitrites* promote deamination of cytosine, adenosine, and guanine to form uracil, hypoxanthine, and xanthine, respectively. *Base Excision Repair* repairs non-bulky DNA-based alterations. *Glycosylase* cleaves the altered base. *Endonuclease* cleaves the 5' end and *Lysase* cleaves the 3' sugar-phosphate. *Polymerase* replaces the base and *Ligase* seals the nick. #1475

What structure induces sudden muscle relaxation in the setting of someone experiencing sustained, strong muscle contraction?

*Golgi Tendon Organ* *GTOs* are sensory receptors found at the junction of muscle and tendon are innervated by *group 1b sensory axons*. When a muscle contracts against resistance, the increase in *tensions* activates GTOs. They are relatively insensitive to changes in length,. 1b sensory axons synapse onto *inhibitory interneurons*, which in turn synapse/inhibit *alpha motor neurons* #8266

Previously health 43 yo male in early Fall c/o 4wk hx of cough. He initially had a "bad cold" that lasted 10ds. The sneezing, rhinorrhea, and muscle aches have improved, but cough has persisted and worsened. Pt has "bursts of coughing" for several mins and cannot clear mucous. Often induces vomiting. Works as kid's karate instructor. Has not seen a doctor in many yrs. No travel hx. Vitals and PE normal. CXR: --. What is the cause of sxs?

*Gram -- coccobacillus* *Pertussis (whooping cough)* occurs in adults w/ waned immunity. Adults present w/ tracheobronchitis w/o vaccine boosters. Utilizes *Pertactin*, which is what the vaccine has, promotes *adherence* to RR epithelium. 1) *Catarrhal Phase*: like other URTIs 2) *Paroxysmal Phase*: severe coughing spells w/ post-tussive emesis 3) *Convalescent Phase*: cough improves #11630

LM 12ds after MI would show what?

*Granulation tissue and neovacularization* #41

35 yo female c/o vulvar lesion, occasional HAs, and memory loss. Admits to polygamy w/o protection. Cardio PE: diastolic murmur w/ prominent second heart sound. There's a painless induration on her vulva. Cervical culture -- for gonorrhea. VDRL+. CXR: calcifications on ascending aortic arch. Blood cultures --. LP: mild pleocytosis and VDRL +. HIV --. What best describes vulvar lesion?

*Gumma* Pt has *late (tertiary) syphilis* and her vulvar lesion is a *gumma* (white-gray and rubbery). May be asymptomatic, or cause subacute meningoencephalitis, tabes dorsals, or other neurologic sequelae. Note: neurosyphilis is most common in tertiary phase but can happen at *any stage* #651

What HBV seromarker indicates increased risk of vertical transmission from mother to fetus?

*HBe Ag* This is associated w/ high infectivity and ability to transmit to fetus #378

2mo female born to immigrant w/o prenatal care. Mother has serum + HBsAg, HBeAg, and anti-HBc, but anti-HBs--. Pt exclusively breastfeeds and grows normally. Vitals and PE normal. No hepatomegaly or jaundice. Infant labs show what?

*HBeAg* Mother is in a *high infectivity state* due to high viral load and *HBeAg+*, increasing risk of vertical transmission. Infants will have high viral load and HBeAg+ despite being asymptomatic--*"immune-tolerant"*. High risk of cirrhosis and hepatocellularCA in infant. #46

25 yo male presents w/ fever, fatigue, and anorexia. Admits IV drug use and unprotected sex. Condition is treated and he's discharged. Pt f/u for 8mos for seromarkers. PT has anti-HBcAg IgM for 4.5mos; anti-HBcAg IgG for 8mos (and still going); HBsAg and HBeAg can be found throughout. What is the pt's state?

*Had acute Hepatitis B that has progressed to chronic hepatitis with high infectivity* *HBsAg* is present prior to sxs and peaks w/ peak illness (will be undetectable w/in 3-6mos unless it goes chronic) *HBeAg and HBV DNA* can be *detected shortly after HBsAg appears* and after *markers of active viral replication* *Anti-HBc Ag IgM* appears after sxs onset and is quickly replaced by *anti-HBc Ag IgG* w/in a few months *Anti-HBeAg* appears shortly after *HBeAg vanishes* and suggestive of *subsiding viral activity* (transition from high infectivity->low) *Anti-HBsAg IgG* appears w/ *acute resolution* (unless it goes chronic) and tends to appear after HBsAg goes away--life long immunity *HBsAg and HBcAg* persistence w/ low *anti-HBcAg* and no anti-HBsAg suggest *highly infective chronic hepatitis* #379

What bias/effect will most likely occur when someone know's their behavior is being studied?

*Hawthorne Effect* #1302

What does a +Prussian blue stain on lung Macs containing golden cytoplasmic granules mean?

*Heart failure due to LV dysfx*. Pulm edema Increased pulmonary capillary P.->Increased permeability of capillary walls -> extravasation of RBCs -> Macs consume -> HF cells -> +Prussian Blue (detects intracellular Fe+2) #185

ETEC Toxins

*Heat-Labile Toxin*: overactivates adenylate cyclase, increasing cAMP, and increasing Cl- secretion from gut and osmotic diarrhea *Heat-Stable Toxin*: overactivates guanylate cyclase, increasing cGMP, and increasing Cl- secretion from gut and osmotic diarrhea

What enzyme causes a bruise to go from blue to blue-green?

*Heme Oxygenase* RBC destruction causes release of Fe+2-containing heme. *Heme Oxygenase* (found in macrophages) degrades *heme into biliverdin*, Carbon Monoxide, and ferrous iron. Biliverdin is *green* and then further reduced to *yellow pigmented bilirubin* via *Biliverdin Reductase*. #1456

22 yo male suffers a knife wound to the neck. Vitals are stable and pt is alert. Neurologic exam: R-sided hemiparesis and loss of proprioception and vibratory sensation below C8 dermatome on R side. On the L side, there is loss of pain and temperature sensation below T2 dermatome. MRI of the pt's spine would show what?

*Hemisection of the right side of the cord* Pt has *Brown-Sequard Syndrome* due to R-sided *hemisection* of the spinal cord. Lesions: 1) *Anterior Horn* (LMN): ipsilateral flaccid paralysis at the level of lesion 2) *Corticospinal* (UMN): ipsilateral spastic paralysis below level of lesion 3) *Dorsal Column*: ipsilateral loss of touch, vibration, and proprioception below level of lesion 4) *Spinothalamic*: contralateral loss of pain and temperature 1-2 levels below level of lesion #12030

63 yo male c/o abdominal pain. PE: abdominal tenderness w/o guarding or rebound. Labs: Hb 8.9 (low), Platelets 134,000, total bilirubin 6.3 (high), LDH 740 (high), and haptoglobin is low. Abdominal MRI: mesenteric vein thrombosis. Flow cytometry: absence of CD 55 on RBCs. What is the pathologic renal finding?

*Hemosiderosis* *Paroxysmal Nocturnal Hemoglobinuria* is due to a gene mutation in *PIG A gene*, which synthesizes the *GPI anchor* for *CD 55* (decay accelerating factor) and *CD 59* (MAC inhibitory protein) that inactivates C'. Absence of these proteins leads to *uncontrolled C'-mediated hemolysis*. Features: -*hemolytic anemia/hemoglobinuria* -*thrombosis* at atypical sites -*pancytopenia* *Fe+2 deposition* in kidney (hemosiderosis) interferes w/ PCT fx and causes interstitial scarring and infarcts. Increased risk for CKD. #11869

22 yo male w/ fever and joint pain has atypical lymphocytes in his blood smear. Its found that he's infected w/ an enveloped virus containing partially ds circular DNA. An enzyme packed in its vision has RNA-dep-DNA-Poly activity. Name that virus!

*Hepatitis B Virus* #376

34 yo male c/o 2d hx of n/v anorexia, and dark-colored urine. Just returned from Mexico. Vitals: 100.2F, BP 125/70, and HR 94. Cardiopulmonary PE normal. Mild RUQ tenderness w/o rebound or guarding. Serologic Entamoeba histolytica --. What would be seen on liver biopsy?

*Hepatocyte Swelling* Sxs are highly suggestive of *Acute Viral Hepatitis*, most likely *Hep A* b/c of epidemiology. Histo: mononuclear infiltrate and hepatocyte necrosis (*cellular swilling and cytoplasmic empyting=> "ballooning degeneration"*) #1863

37 yo male brought to hospital for pneumonia and tx lasts 2d. He gets better. However, he now c/o new-onset abdominal pain, diarrhea, and severe muscle aches. No hx of GI complaints but admits to recreational drug use. PE: appears uncomfortable and yawns frequently. BP 124/80 and HR 88. Pupils are dilated w/ prominent lacrimation. Abdominal exam shows hyperactive bowel sounds w/o tenderness or distention. What is the most likely dx?

*Heroin withdrawal* *Sxs*: n/v, abdominal cramps, and muscle aches *Exam findings*: dilated pupils, yawning, lacrimation, piloerection, and increased bowel sounds #1353

Even w/ Fructokinase deficiency, how can someone maintain normal fructose metabolism?

*Hexokinase* takes over and converts dietary fructose to *Fructose-6-Phosphate*. It can now be metabolized in glycolytic pathway or converted to Gluc-6-Phosphate or Gluc-1-Phos. Condition is called *Essential Fructosuria* #1070

A pt w/ CKD will have what levels of PTH and serum Ca+2?

*High PTH and Low serum Ca+2* *CKD* pts have *decreased PO4- clearance* b/c of *decreased GFR*. The *increased PO4-* in serum then binds serum Ca+2, causing *hypoCa+2*. Loss of renal parenchyma causes decreased Vitamin D, further deceasing Ca+2. Increased PO4- and decreased Ca+2 stimulates *Secondary Hyperparathyroidism* #979

A new inhaled Drug A is being compared to NO. Their partial Ps. are compared. NO peaks significantly faster than Drug A, but they eventually level off w/ each other. What best describes the properties of the new anesthetic compared to NO?

*High blood/gas partitioning coefficient* Partial pressure of drug rises until it matches that of inspired gas and is not said to be saturated. *Speed of saturation* is dependent on the *drug solubility*. Blood solubility of an anesthetic is indicated by its *blood/gas partition coefficient* (they're directly proportional). *NO* has low solubility and thus a low blood/gas partition coefficient, which is why it saturated so fast. Solubility is inversely proportional to the amount of gas needed to equilibrate w/ brain and onset of action #659

What finding is most suggestive of increased insulin resistance in T2DM?

*High waist circumference* *Excess visceral fat* (surrounding internal organs) correlates more strongly w/ insulin resistance than subcutaneous fat. Measuring *waist circumference* or *waist-to-hip ratio* indirectly measures visceral fat. Waist circumference >102 cm (male) and >88 cm (female) is associated w/ increased insulin resistance, diabetes, and CAD x *other signs:* -increased hepatic gluconeogenesis -dyslipidemia as seen by increased TG and decreased HDL (no change to LDL) -decreased glucose uptake in skeletal muscles and decreased glucose oxidation and glycogen synthesis #1327

Early-stage Alzheimer Disease presents w/ atrophy where?

*Hippocampus* -will progress to temporoparietal atrophy and then diffuse atrophy in late stage #794

What protein forms the outside core of the "bead" on "beads on a string" found in chromatin fibers?

*Histone H1* *Nucleosome core* is made of (H2A, H2B, H3, and H4)2, which *H1* is located on the *outside of histone core*. H1 binds *linker* segments of DNA that lie btwn nucleosomes and *facilitate packaging of nucleosomes* #1472

38 yo male w/ c/o pain in multiple joints. Has a 5yr hx of lumbar pain and a 2 yr hx of bilateral knee pain. He works in construction and pain is worse at the end of the day. Ibuprofen does little. Pt has paternal aunt w/ osteoarthritis. PE: blue-black spots on his sclerae and diffuse darkening of the auricular helices. What is this pt's cause of arthritis?

*Homogentisic acid dioxygenase deficiency* *Alkaptonuria* is a benign childhood disorder that causes *arthritis in adults*. Its an *AR disorder* due to a deficiency in *homogentisic acid dioxygenase*, which metabolizes *homogentisic acid-> maleylacetoacetate*. Accumulation of homogentisic acid causes *pigment deposition in connective tissue*, seen as *blue-black deposits* in adults (especially sclerae and ear cartilage). It it effects spine, then it causes ankylosis, motion restriction, and significant pain -*urine turns black when exposed to air due to oxidation of homogentisic acid* #1503

9mo female had 2 minute generalized seizure. Pt has fever for past 12hrs and has been fussy. PMH:--. Temp 103F. PE: normal. Discharged. 3ds later, she's afebrile but developed a maculopapular rash on her trunk. What is she infected with?

*Human Herpesvirus 6* Pt has *Roseola Infantum* from *HHV 6* infection. This is classic presentation. The rash *starts on trunk* and progresses to face and extremities. Self-limited #11822

What hormone contributes to developing GDM?

*Human Placental Lactogen* *Maternal insulin resistance* tends to occur in *second and third trimesters* and is mediated primarily by *hPL*, a peptide hormone secreted by *syncytiotrophoblasts*. hPL also increased maternal lipolysis. hPL *stimulates pancreatic B cell insulin production*. Screening for GDM is more accurate in 3rd trimester and done via *oral glucose challenge*. #8330

43yo male w/ HIV is non-compliant w/ his meds and c/o progressive memory loss and cognitive decline over past several yrs. He has problems w/ attention, concentration, and speech. In past few pos, he's become more apathetic and increasingly lethargic. More recently, he's had difficulty w/ balance and has had multiple falls. -- for: HA, tremor, vision change, fever, n/v, or urinary incontinence. Fam hx: brother has sever intellectual disability and seizures. His MMSE is 18/30. Head CT: diffuse cortical atrophy w/ enlarged ventricles. Dx?

*Hydrocephalus Ex-Vacuo* Its w/ neurodegenerative diseases (*AIDS Dementia*) have significant *cortical atrophy*, which allows the ventricles to expand while maintaining *normal CSF pressure.* This gives the *appearance of increased CSF* on imaging, but *ICP is normal.* This condition is known as *Hydrocephalus Ex-Vacuo* -note: his brother may or may not have Lissencehaly due to congenital absent gyri tho... #14

74yo female w/ multiple comorbidities, including HTN, T2DM, and CHF, experiences a hip fracture. What diuretic would have decreased risk of fracture?

*Hydrochlorothiazide* *Thiazide diuretics* are especially recommended for HTN pts w/ DM. They *inhibit Na+/Cl- supporter in DCT*, decreasing Na+ reabsorption. They also cause peripheral vasodilation, decreasing peripheral vascular resistance. There's *increased Ca+2 reabsorption* in DCT. #993

73yo male c/o severe chest tightness and dyspnea, which started several hrs ago at dinner. No hx of similar sxs. PMH: HTN, hyperlipidemia, T2DM, and prostate cancer. 30 pack yrs but quit 10yrs ago. Chest CT: saddle pulmonary embolus. What contributed to this pt's condition?

*Hypercoagulability* PMH of prostate *cancer*, smoking, and increased age increased risk of developing a *venous thromboembolism* (DVT-> PE/Saddle Embolus). *Virchow's Triad*: endothelial injury, venous stasis, and *hypercoagulable state* (cancer!) #1880

58 yo male c/o sudden R-sided weakness. No other stroke-like sxs. He's previously been told that he has HTN, but does not take any meds. Fam hx: mom w/ CAD and dad died of stroke. PE: normal cranial nerve function but 3/5 strength on R side. Initial CT: no abnormalities. 4wks later, there's a 9 mm, fluid-filled cavitary lesion in L internal capsule. This pt's condition is cause by what?

*Hypertensive Arteriolar Sclerosis* Pt has a *Lacunar Infarct*, which is a form of *ischemic stroke involving small penetrating arterioles* that supply deep brain structures (basal ganglia and pons) and subcortical white matter (internal capsule and corona radiata). These infants are due to *chronic HTN*, which promotes *hypertensive arteriolar sclerosis* #22

In normal female development, non-fusion of urethral folds forms vestibule of vagina. In males, non-fusion of urethral folk would cause what?

*Hypospadias*--opening of *ventral* surface of penis #1870

34 yo male w/ c/o excessive thirst and frequent urination. This happened several yrs ago and tx worked, but he's run out of meds. His urinary Osm after 2hrs of water restriction is 250 mOsm/L and increases to 700 mOsm/L w/ administration of ADH. Persistence of pt's condition is likely due to damage of what structure?

*Hypothalamic Nuclei* Pt has *Central DI* due to *imparied ADH production*. ADH is synthesized in *paraventricular and supraoptic nuclei of hypothalamus* and stored in Posterior Pituitary. Damage to hypothalamic nuclei causes *permanent* central DI. -may also see other sxs: autonomic dysfx, eating disorders, and temperature dysregulation -Note: damage to Posterior Pituitary will only cause *transient* central DI #206

14yo male in for WCV. He's tall but looks younger than his peers and no signs of "masculinity." PE: poorly developed secondary sexual characteristics. He's unable to distinguish smells but has good visual acuity. What pathway is defective?

*Hypothalamus->Pituitary* *Kallmann Syndrome* is characterized by anosmia and delayed puberty. It is due to *failure of GnRH-secreting neurons* to migrate from olfactory to hypothalamus. Mutation in KAL-1 or FGF-1 receptor genes #579

2 mo male broth to ER b/c of progressively worsening "floppiness" and poor feeding. Infant born in Eastern Europe and immigrated to America. Has been known as a "good baby" but lately has been difficult to rouse for breastfeeding. Stools have decreased to every other day and are small and pellet-like. PE: hypotonic infant w/ a large anterior fontanelle, large tongue, and irreducible umbilical hernia. He has low tone and unable to erect on his own. No other abnormalities. What is the cause of pt's condition?

*Hypothyroidism* Pt has *Congenital Hypothyroidism* associated most commonly w/ thyroid dysgenesis or *maternal iodine deficiency* (seen in Europe). Maternal placental transfer of T4 decreased initial neonatal sxs. Overtime, T4 concentration in neonate decreases, impairing metabolism and marked slowing of physical and mental activity. Accumulation of metric substances causes non pitting edema (*puffy face*), *umbilical hernia*, protruding tongue, and large anterior fontanelle. Infants are at increased risk of *irreversible intellectual disability* b/c of poor brain development and myelination due to absent T4. -tx w/ *Levothyroxin* by 2wks to normalize cognitive and physical development #1407

45 yo smoker w/ PMH of HTN and DM. Goes to ER w/ STEMI. While in cardiac Cath lab, he develops cariogenic shock requiring vasopressors. Dies of V-fib. Autopsy shows bilateral wedge-shaped strips of necrosis over cerebral convexity, parallel to and a few centimeters lateral to the longitudinal cerebral fissures. Findings described are caused by what?

*Hypoxic-Ischemic Encephalopathy* Pt w/ cariogenic shock and *watershed necrosis* on autopsy most likely suffered from *HIE*. *Systemic hypoTN* caused global ischemia. Due to lack of glycogen storage in CNS, the brain is very susceptible to ischemia. -*Pyramidal cells of hippocampus* and *Purkinje cells of cerebellum* are most vulnerable to ischemic injury -*watershed zones* are at the *borders* btwn the areas perfused by anterior, middle, and posterior cerebral As. #23

5 yo male w/ severe recurrent RR infections. A specific type of bacteria is causing them. Tests show pt's T cells lack IL-12 R. Supplementation w/ what will improve condition?

*IFN-g* A deficiency in IL-12 R. would *prevent TH0->TH1* differentiation. Thus, no IFN-g production would occur to activate macrophages. -inability to do Type 4 hypersensitivity or kill intracellular pathogens -TH0->TH1 requires IL-12 and IFN-g #762

65 yo male c/o 3d hx of HAs localized to R. temporal region that's accompanied by bilateral intermitted blurred vision. Also c/o fatigue and stiffness in shoulders and hips for 1wk. Afebrile. Tender to palpation of R. temporal region w/ enlargement of underlying A. Fundoscopy: edematous optic discs bilaterally. Labs: elevated ESR (115). What is the most important mediator of pt's condition?

*IL-6* Pt has *Giant Cell Arteritis/Temporal Arteritis* w/ assoc. *Polymyalgia Rhematica* -common in Europeans >50yo -inflammatory infiltrate primarily CD4 and macrophages forming giant cells -can treat w/ *Tocilizumab* (mAb against IL-6) #11770

What is the main mediator of increased ESR?

*IL-6* The liver responds to inflammatory cytokines (IL-1, *IL-6*, TNF-a, and IFN-g) to release *acute phase reactants* and increase ESR #1801

37 yo male c/o increasing pain in his R forearm. He got in a fight 6d earlier and sustained a 4 cm laceration. Tx included cleaning and dressing. PE: erythema and yellow pus. What molecule mediated the pus to form?

*IL-8* *Pus* is generated by dead *PMNs*. Macrophages produce a strong *PMN chemoattractant, IL-8* (which also induces phagocytosis) #8539

28 yo female receives IV morphine sulfate for kidney stone pain. 15 min later, she develops diffuse itching involving the arms, legs, and back. What mechanism caused this reaction?

*IgE-independent mast cell degranulation* Pt has *Redman Syndrome*, which is induced by *opioids, radiocontrast agents, and Vancomycin*. This *IgE-independent* mast cell degranulation is induced by activation of *Protein Kinase A and PI3 Kinase*. #11852

8 yo male w/ c/o fever, throat pain, and difficulty breathing. Not immunized. Throat PE: extensive, coalescing gray pharyngeal exudates and cervial LAD. Dies of myocarditis. Presence of what would have prevented death?

*IgG against circulating proteins* Pt is infected w/ *Corynebacterium diphtheriae*, a non-invasive G+ pleomorphic bacteria that colonizes the pharynx and produces a *toxin that inhibits protein synthesis through ADP-ribosylation of EF-2* This toxin would be *neutralized by IgG* (AB toxin) #1092

Elderly female w/ 2-d hx of abdominal cramps and vomiting w/o any other sxs. Months ago had acute calculous cholecystitis w/o operative tx. PE shows distended, tympanic abdomen w/ high pitched bowel sounds. Abd. Xray shows air in biliary tree and gallbladder. Gallstone is found where?

*Ileum* *Gallstone ileus* is an uncommon complication of longstanding cholelithiasis. Gallstone causes formation of *cholecystoenteric fistula*, normally found on duodenum, but stone gets lodged in *ileum*. #1525

3wk old male is lethargic. He was born at home and has no vaccinations. Head circumference in 99th %. Wt and ht 25th %. PE: large, bulging anterior fontanel. Eyes appear downward and pt is not able to track upward. No scalp swelling present. Intercranial hemorrhage dx by CT. What is the cause of pt's condition?

*Impair clotting factor carboxylation* Neonates have a sterile gut and cannot produce their own Vitamin K yet. Routine procedure is to administer Vitamin K perinatal. *Impaired Vitamin K-depending clotting factor production* caused the *intercranial hemorrhage*. #1062

What is Flutamide's MOA?

*Impaired Androgen-Receptor Interaction* *Flutamide* is a nonsteroidal that acts as a *competitive testosterone R. inhibitor*. Prevention of androgen-R. binding blocks stimulatory effects on primary tumor and metastases and leads to a decrease in their size. #657

31 yo female c/o transient visual changes that are characterized by a "loss of vision for a minute" and are commonly attributed to lifting object. HAs have persisted for 6mos. Vitals: BP 140/90 and HR 72. BMI 32.4. Fundoscopy: bilateral papilledema. What is the cause of the abnormal fundoscopy?

*Impaired optic nerve axoplasmic flow* Pt has *Idiopathic Intracranial HTN* (Pseduotumor Cerebri), which is consistent w/ a young obese female w/ *daily HA*, bilateral papilledema, and *transient visual disturbances* related to impaired cerebral venous flow or increased ICP. Increased ICP-> compresses optic N.-> *impairs axoplasmic flow* w/in optic N.-> *bilateral papilledema* #12257

16yo female c/o pelvic pain and abdominal crampy pain that occurs each month and resoves in 2ds. Pain began 6mos ago and has been progressively worsening. Pt has never had a menstrual cycle. Has never had sexual intercourse. Wt, ht, and BMI are normal for age and sex. She has fully developed secondary sexual characteristics. PE: palpable mass anterior to rectum. B-hCG --. Dx?

*Imperforate Hymen* *Imperforate Hymen* is due to the incomplete degeneration of a fibrous band connecting the walls of the vagina. Pt will present w/ *Primary amenorrhea* and normal secondary sexual characteristics w/ *cyclic abdominal or pelvic pain* due to accumulation of blood in uterus (*hematocolops*). Will have a vaginal bulge anterior to rectum. #8390

Newborn male in NICU born to a 40 yo female w/o prenatal care. PE shows slate palpebral fissures, epicentral folds, thick nuchal folds, and a single palmar crease. Pt has a large, reducible midline abdominal protrusion covered by skin that is more pronounced w/ crying. Umbilical stump is center of protrusion. What caused this?

*Incomplete closure of the umbilical ring* Pt has *Down syndrome* and *Umbilical Hernia*. Umbilical ring failed to close, which normally forms linea alba, allowing for protrusion -they're asymptomatic and resolve spontaneously in a few yrs #11803

Child w/ heritable disorder has a single nucleotide substitution in G->A w/in an [intron] (5'...[CAG]GTA...3'). This causes a loss of fx motion in the affected protein. What was the most likely effect of this mutation?

*Incorrect splicing of pre-mRNA* *Spliceosomes* remove introns containing *GU at 5' splice site and AG at 3' splice site* #2038

What hormone pattern is seen w/ Klinefelter syndrome? (LH, FSH, Testosterone, Sperm count)

*Increase LH; Increase FSH; Decreased Testosterone; No Sperm* #582

68 yo male w/ Myasthenia Gratis is experiencing worsening of his sxs. He is currently on a low-dose Pyridostigmine. Infusion of Endrophonium significantly improves sxs. What is the next step in management?

*Increase Pyridostigmine Dose* *Pyridostigmine*, a long-acting AChEi, wasn't working b/c the pt was receiving a suboptimal dose and not enough ACh was at the NMJ, inducing *Myasthenic Crisis*. This is detected via *Tensilon Test (Endrophonium)* to see if sxs improve. -*Cholinergic Crisis* is when the dose is *too high*. They will be *Tensilon Test--* and AChE should be temporarily discontinued #1320

How is CO maintained in Aortic Regurgitation?

*Increase in left ventricular stroke volume* *AR* causes increased back flow to LV, causing *increased preload* (EDV), increased wall stress, and *eccentric hypertrophy*. Gradual increased eccentric hypertrophy causes *increased stroke volume* to maintain CO. -There is also decreased afterload. #237

37 yo female G3P1 at 28 wks gestation c/o loss of urine w/ cough. Uneventful pregnancy. PMH:--; BMI prior to pregnancy 32. Gained 32 lb during pregnancy. Urine culture --. What is the mechanism for urinary incontinence?

*Increased Abdominal Pressure* *Stress incontinence* is a frequent pregnancy complaint. Pregnancy hormones al *decrease urethral tone* and relax pelvic floor muscles (*levator ani and coccygeus*), which mediate urethral tone. There may also be *urethral hyper mobility*. #11926

44 yo male gets in MVA and an arteriovenous shunt is developed w/ injury. What is most likely to happen to LV P/V loop?

*Increased Cardiac Preload* An *AV fistula/shunt* allows for blood under arterial Pressure to enter venous circulation. *Preload increases* by increasing rate and volume of blood back to heart #1518

44 yo female c/o persistent back pain associated w/ radiation of vertebral metastasis from breast cancer. She's started on oral morphine. What is the most likely direct effect of this medication on the spinal cord neurons?

*Increased K+ efflux out of cells* *Morphine* is an *opiate analgesic* for chronic pain in cancer pts. All opiate Rs. are coupled to *Gi proteins*. *At the spine*, Rs. on primary afferent neuron causes *closure of v-gated Ca+2 channels*-> decreased Ca+2 influx -> decreased excitatory NT release from the *presynaptic terminal*. Opiates can also bind to *postsynaptic mu Rs.*-> *open K+ channels* -> *K+ efflux*-> membrane *hyperpolarization* #776

65 yo male w/ extertional dyspnea and easy fatiguability. Not been to doc in 10yrs. Smokes 1ppd, drinks 7-10 beverages/wk, and no meds. Vitals: BP 170/90 and HR 90. PE: bilateral lung crackles. What changes to LV EDP, LV EDV, and LV EF would be seen?

*Increased LV EDP; Normal LV EDV; Normal LV EF* Pt has *Diastolic HF*. Diastolic dysfx is due to conditions that *decreases LV compliance*, such as impaired relaxation or increased wall thickness #186

50yo male w/ Polycystic Kidney Disease c/o constant, deep pain in his shoulders, arms, and legs. PMH: HTN and Ramipril. Vitals: BP 150/85 and HR 78. Cardiopulm PE: normal. Abdominal PE: large, palpable renal masses. Bilateral lower extremity edema present Labs from 2yrs ago show BUN 25 and Cr 2.3. Current Labs: Na+ 136 (n), K+ 4.8 (n), Cl- 104 (n), HCO3- 22 (n), BUN 66 (high), Cr 5.5 (high), and Ca+2 7.5 (low). What metabolic state is this pt in? (Phosphate, PTH, and Calcitriol)

*Increased Phosphate; Increased PTH; Decreased Calcitriol* Pt is in *Metabolic Bone Disease* due to *Chronic Kidney Disease*. Decreased GFR causes *decrease PO4- filtration* (more is reabsorbed) and hyperphosphatemia decreases serum Ca+2 and stimulates FGF-23, which *decreases calcitriol synthesis*. HypoCa+2 and hyperPO4- stimulate *PTH release*. Prolonged PTH release will cause *osteitis fibrosa and bone pain* #11977

Pt w/ hx of depression and HTN found unconscious. She is hypotensive and bradycardia. IV glucagon is administered and condition improves. What intracellular changes occurred that improved her condition?

*Increased cAMP in cardiac myocytes* Pt *overdosed on B-blockers* causing depressed myocardial contractility, bradycardia, and AV block. *Glucagon* is the *reversal drug*--it acts on GPCR to increased intracellular cAMP that increases intracellular Ca+2 #1444

What labs are seen w/ autoimmune gastritis? (gastrin lvls; gastric pH; parietal cell mass)

*Increased gastrin; high gastric pH; decreased parietal cell mass* Pts w/ *Pernicious Anemia* have CD4 mediated destruction of parietal cells. Decreased intrinsic factor causes B12 deficiency/megaloblastic anemia. Loss of parietal cells means *decreased gastric acid* (increasing gastric pH). The increased gastric pH stimulates increased gastrin release. #12068

56yo male admitted b/c of severe dehydration secondary to excess output from ileostomy. Total colectomy 5yr ago w/ diverting ileostomy b/c of colon cancer. For the last 6mos, he's had increased ileostomy output and hospitalized twice for dehydration. On 2nd day of admission, he develops R flank pain. Abdominal Xray: nonspecific bowel gas pattern w/o evidence of renal calculi. Abd US: 4 mm stone in distal R ureter. Stone passes spontaneous diamond-shaped stones. What is the underlying mechanism leading to stone formation?

*Increased hydrogen ion excretion in the kidney* *Uric acid stones* are yellow/brown *diamond/rhomboid-shaped* crystals that are *radiolucent* (Xray--). Risk factors: *decreased urine pH* and low urine volume w/ *high uric acid concentration*. Pt's *recurrent dehydration/diarrhea* decreased HCO3- reabsorption from gut, leading to chronic metabolic acidosis. The kidneys compensated and *increased excretion of H+* and increased reabsorption of HCO3-, *acidifying the urine*. #12081

What is seen on biopsy of a pt w/ Dermatitis Herpetiformis?

*Increased intestinal intraepithelial lymphocytes* *Dermatitis Herpetiformis* is characterized by erythematous pruritic papule, vesicles, and bullae that appear bilaterally and symmetrically on extensor surfaces, butt, and upper back. Histo: *microabscesses* containing fibrin and PMNs at the *dermal papillae* tips. DH is strongly associated w/ *Celiac Disease*, which is due to *IgA Abs* against *gliadin*. GI Histo: *Increased intraepithelial lymphocytes* and variable loss in villus ht. #1111

8yo male w/ CF has a nasal transepithelial potential difference that is more -- than normal. The pt's mucosa most likely demonstrates what physiologic changes?

*Increased sodium absorption* Normal respiratory epithelium has an *ENaC coupled to CFTR channel*. CFTR normally pumps out Cl- and has an inhibitory effect on ENaC not allowing Na+ to move into the cell. The lack of CFTR increases Na+ reabsorption and the potential difference is more --. Note: CFTR fx is reversed in *sweat glands* compared to nasal and intestinal mucosa; CFTR in sweat glands is supposed to increase reabsorption of Na+ and Cl-, thus a CFTR mutation induces high sweat NaCl content. #804

63 yo male w/ hx of MI has been noncompliant w/ his meds and is c/o several days hx of acute decompensated HF, as seen by orthopnea, bibasilar lung crackles, JVD, and bilateral pitting LE edema.CXR: cardiomegaly and pulmonary venous congestion. What is most likely causing the pt's sxs?

*Increased sympathetic nervous system activity* *HF* is ultimately a *decrease in CO*, which is detected by initial decrease in BP triggering *compensatory neurohormonal stimulation* to maintain BP and perfusion. This stimulation is mainly mediated by *increasing SNS activity* to stimulate ADH and RAAS activity to increase CO by increasing ionotropy and chronotropy. *Adverse effects*: 1) *Increased afterload from excessive vasoconstriction* further decreases CO and causes fluid retention, causing decreased renal perfusion 2) *Increase RAAS* increases fluid retention #8546

52 yo female on f/u for menopausal sxs is on an estrogen and progesterone OCP to tx severe hot flashes. PMH of diet-controlled HTN, but no meds. Labs: normal TSH. What will most likely occur as long term effect of meds?

*Increased total T4 pool* 99% of TH is bound to *Thyroxine-binding globulin*. TBG increases w/ *estrogen activity*, thus increasing TBG levels. This causes *transient decrease in T3 and T4*; however, in order to maintain HPA axis homeostasis, *T3 and T4 are produced* to match TBG (Total T3 and T4 will increase) #727

4d old female born to G5P4. Breastfed exclusively w. difficult feeding in past 24hr. She's been "too sleepy to feed" and vomiting. Has 3 healthy siblings but 1 brother who died of "low blood glucose." PE: tachypnea and signs of dehydration. Pt is only responsive to pain stimuli. Urine shows increased methylmalonic acid. What lab pattern is seen w/ this condition? (Urine propionic acid, serum glucose, urine ketones, and serum ammonia).

*Increased urine propionic acid; decreased serum glucose; increased serum ketones; increased serum ammonia* Pt has *Methylmalonic Acidemia*, an *AR organic acidemia* b/c of deficiency in *methylmalonyl-CoA Mutase* that converts methylmalonyl CoA-> Succinyl-CoA (*using B12*). Metabolic sxs present as hypotonia, lethargy, vomiting, and respiratory distress. #1341

5 yo male w/ prolonged epistaxis. Hx of hemarthrosis in R. knee. Has a maternal uncle w/ hx of hemarthrosis and prolonged bleeding after dental procedures. Pt receives desmopressin and stops bleeding. What is the therapeutic mechanism?

*Increases circulating factor VIII* Fam hx, pt hx, and response to decompressing are consistent w/ *X-linked Hemophilia A* (*Factor VIII deficiency*) -*Desmopressin* increases circulating VIII and vWF #942

24yo w/ SLE has labs that reveal several types of autoAbs directed against components of the cell nucleus. One targets proteins complexed w/ small nuclear ribonucleic acid. These complexes have what cellular fx?

*Removal of introns from RNA transcripts* *Smith protein* normally complexes w/ *small nuclear RNA (snRNA)* in the cytoplasm to form *snRNPs* and other proteins. They recognize introns based on a *5' GU donor site* and a *3' AG acceptor site* w/in introns #361

5 mo male w/ R-sided scrotal enlargement. Its been present since birth and increases w/ crying or BM. No hx of trauma or infection. No pain associated w/ it. No discoloration. US: fluid collection around R. testis. This embryologic defect can also lead to what else?

*Indirect Inguinal Hernia* Pt has *failure of obliteration of processus vaginalis*, allowing for continued connection btwn scrotum and peritoneum via inguinal canal--causing *Communicating Hydrocele* in this pt. -fluid leakage into tunica vaginalis -increased size w/ Valsalva -if passage is large enough, increased risk of *indirect inguinal hernia* #419

21 yo male brought to ER in a stuporous condition. He returned from Mexico 2wks ago. One wk ago, pt began developing high-grade fever, severe myalgias, and joint pain. He had similar sxs w/ a trip to Mexico 5yrs ago but sxs did not progress and resolved spontaneously in 5ds. Vitals: 101F, BP 80/50, and HR 128. PE: diffuse maculopapular rash, multiple purpuric lesions, and hepatomegaly. Labs: thrombocytopenia, leukopenia, and increased liver aminotransferases. What is the mechanism of severe illness?

*Infection with a different viral serotype* Pt has *Dengue Hemorrhagic Fever*, which is caused by a +ssRNA flavivirus transmitted by the Aedes mosquito. There are 4 serotypes. *Primary infection* may be asymptomatic or if symptomatic they'll experience fever, HA, *retro-orbial pain*, bleeding, *diffuse maculopapular rash*, muscle and joint pain, leukopenia, and thrombocytopenia. *Secndary infection by a different serotype* causes a more severe infection due to Ab-dependent enhancement of infection w/ accelerated T cell response. There will be *shock and + tourniquet test* #11395

What landmark would a surgeon use to distinguish btwn an indirect and direct inguinal hernia?

*Inferior Epigastric vessels* #418

42 yo male is found to have internal hemorrhoids. During anoscopy, building purple-blue mucosal lesions above dentate line are noted. Rubber ligation of the lesions is most likely to involve what vessel?

*Inferior Mesenteric Vein Tributaries* *Internal Hemorrhoids* occur *above the dentate line* and are a results of abnormal distention of the anal arteriovenous plexus system. Internal hemorrhoids drain into the *superior rectal vein*, which communicates w/ the *inferior mesenteric vein* (ultimately goes to the *portal system*) #11840

36 yo female experiences weakness in hands and heaviness of eyelids. CXR shows anterior mediastinal mass. The organ from which the mass most likely originates shares its embryonic origin w/:

*Inferior Parathyroid Glands* -Question referenced thymus -note: Mysthenia Gravis is assoc. w/ Thymomas #756

29 yo G2P2 female c/o fever, crampy abdominal pain, and R. flank pain 8d after uncomplicated vaginal delivery. CT shows R. ovarian venous thrombosis. If untreated, where would thrombus go?

*Inferior Vena Cava* Pt has *Postpartum Ovarian Venous Thrombosis*. *L. ovarian V.*->*L. Renal V.* *R. ovarian V.*->IVC -R-sided is the most common #19920

23 yo male stabbed in RUQ. Stab wound is 2cm inferior to the R. costal margin. Brisk, nonpulsatile blood is seen emanating from behind liver. Surgeon occludes hepatoduodenal ligament, but pt continues to hemorrhage. Where is the source of bleeding?

*Inferior Vena Cava* The *Portal Triad* runs through the *hepatoduodenal ligament* (hepatic A., hepatic portal V., and common bile duct) -would either be IVC or hepatic V. #10583

59 yo male c/o recent unintentional wt loss and epigastric discomfort after meals w/ occasional nausea. He reports that food is not as appetizing as it used to be. PMH--. Fam hx: father has PUD. Stomach biopsy: signet ring cells. The lesion demonstrates what?

*Infiltrative growth within the stomach wall* Pt has *Gastric Adenocarcinoma*, specifically *Signet-Ring CA*. There will be *diffuse* involvement of the stomach wall b/c of the *loss of E-cadherin*. Has a plaque-like appearance and is ill-defined--*"linitis plastic"* Metastasis: *supraclavicular* (Virchow LN) or *umbilical* (Sister Mary Joseph LN) #307

Why do appendicitis sxs begun periumbilical and then localize to McBurney's?

*Inflammation of the parietal peritoneum* The pain moves from *visceral abdominal pain* (b/c of luminal distention and smooth muscle stretching) to *parietal peritoneal pain* (somatic pain) #11775

15 yo athlete c/o sudden-onset of severe L. leg pain. She felt a popping sensation and developed anterior leg pain after landing a jump. She's unable to bear wt. PE: swelling of L. knee w/ focal tenderness just above patella. She's unable to raise L. leg while supine. Imaging: complete tear of quadriceps tendon. Lidocaine injection at what site would provide anesthesia for the procedure?

*Inguinal Crease* *Femoral N. (L2-L4)* innervates knee extension and hip flexion, along w/ sensory to anteromedial thigh, shin, and arch of foot. Nerve emerges btwn psoas and iliacus muscles and passes under inguinal ligament (lateral to A.) and into thigh before branching in femoral triangle. Optimal site for *femoral N. block is inguinal crease* at lateral border of femoral A. -also blocks saphenous N. (decreased sensation of medial leg below knee) -femoral N. not w/in femoral sheath #11777

36yo WF has had 3 episodes of DVTs in past 6yrs. PMH: pulmonary saddle embolism. PTT is normal limits and remains unchanged when activated Protein C is added to her serum. What is the cause of her problem?

*Inherited* Pt's persistent hyper coagulable state and *resistance to antithrombotic effects of Protein C* makes *Factor V Leiden Mutation* likely. This makes Va resistant to activated Protein C #465

35yo male w/ PUD has new-onset gouty arthritis. Doc prescribes appropriate medication. Shortly after starting the medication, pt experiences n/v and diarrhea. What is the MOA of this drug?

*Inhibition of microtubule formation* -pt is on *Colchicine* -b/c it says "appropriate med" that rules out inappropriate use of NSAIDs w/ concurrent PUD. Plus, NSAIDs don't tend to cause vomiting and diarrhea #1168

32 yo male got in a fight. He's agitated and says his chest hurts. Vitals: BP 170/100 and HR 130. Pt is combative and uncooperative. Pupils are dilated and reactive to light. Nasal exam shows mucosal atrophy. EKG shows MI. Inhibition of what cellular process is responsible?

*Inhibition of presynaptic monoamine reuptake* -Cocaine and TCAs! #2001

How does the injection of flu vaccine induce immunity?

*Inhibition of viral entry into cells* *Influenza vaccine* is an *inactivated, killed vaccine* that fxs by inducing *neutralizing Abs* against the *hemagglutinin Ag* -b/c its not live, it will not go through the MHC I pathway and will not generate CD8+ lymphocytes #1466

Where is the AV node located in the heart?

*Interatrial septum near the opening of the coronary sinus* -also *septal leaflets of the tricuspid valve* #11956

What is the MOA of Ribavirin?

*Interfering with duplication of viral genetic material* *Ribavirin* and interferon-a are used in *Chronic Hepatitis C infection* (HCV RNA in serum and liver biopsy shows chronic inflammation and fibrosis). Ribavirin is used for HCV and RSV. It is a *nucleoside antimetabolite* that interferes w/ duplication of viral genetic material via several mechs: 1) Must be *phosphorylated* by *adenosine kinase* to incorporate into RNA and *pair w/ Uracil or Cytosine*. This induces *hypermutation of RNA-Dep-RNA-Poly* 2) *Direction inhibition of HCV RNA Poly* by triphosphate 3) Monophosphate *inhibits IMP dehydrogenase*, decreasing intracellular GTP 4) *Inhibits viral RNA guanyl- and methyltransferases*, causing defective 5' cap formation and *insufficient viral translation* 5) *Increases TH1 immunity* and inhibiting TH2 cytokine production #8455

40yo nulligravada female found to have abnormal adnexal mass. W/in the true pelvis, the surgeon most likely palpated the R ureter immediately anterior to what structure?

*Internal Iliac Artery* #1804

24 yo female delivers twins vaginally after prolonged labor. Shortly after placental delivery, there's profuse bleeding and a boggy uterus. Meds and mechanical assistance do not stop bleeding. Bilateral ligation of what artery would control bleeding and preserve fertility?

*Internal Iliac Artery* *Postpartum hemorrhage* risk factors are twins and prolonged labor. This leads to *uterine atony*, characterized by the body uterus. *Internal Iliac Arteries* send of *uterine As.* to provide blood supply to uterus. Ligation of these would stop blood flow and preserve fertility. This is fine b/c the uterus has *collateral circulation from ovarian As.* #11908

Neonate born w/o complications from a normal pregnancy. Evaluation shows abnormal sexual differentiation. Karyotype 46 XY. Biopsy of gonads shows absent Sertoli cells but normal Leydig cells. What phenotype is present?

*Internal Reproductive Organs: Female and Male; External Reproductive Organs: Male* Gonads all start the same; however, w/ the presence of *SRY gene on Y chromosome*, this encodes for testes determining factor--Testes now develop. -*Sertoli cells* suppress female internal organ growth by producing *anti-mullerian hormone* (AMH) and concentrates testosterone -*Leydig cells* secrete *testosterone* to stimulate *Wolffian Ducts* to differentiates into internal male genitalia. Conversion of testosterone->DHEA forms external male genitalia #1449

45yo female c/o exertion dyspnea and fatigue and episodes of pain. Also has bluish discoloration of fingers and toes w/ cold weather. PE: tightening of skin over fingers. Cardiac PE: accentuated 2nd heart sound over upper L sternal border. Abdomen soft w/ mild hepatomegaly. Bilateral LE pitting edema. PFTs: normal. What is the most likely cause of pt's presentation?

*Intimal thickening of pulmonary arterioles* Pt's accentuated 2nd heart sound is indicative of *Pulmonary HTN*, which causes *cor pulmonale* and sxs of R-sided HF. Her *sclerodactyly and Raynaud's* are suggestive of *CREST Syndrome*, which PAH can be a product of. Both forms of systemic sclerosis are ultimately due to collagen deposition w/ proliferation of monoclonal T cells and TBG-B production -*anti-centromere Ab+* #825

35 yo alcoholic presents w/ hematemesis. Prior he vomitied 3x. No jaundice. Normal PE. Endoscopy shows longitudinal mucosal tears at GE junction. Pt's condition is most likely related to what?

*Intraabdominal Pressure* *Mallory-Weiss Syndrome* is secondary to rapid increase in intraabdominal P. assoc. w/ retching and vomiting. -may see hiatal hernias (predisposing factor) #281

76 yo male w/ c/o severe midsternal chest pain and diaphoresis. PMH: HTN, T2DM, and asymptomatic R coronary A stenosis. Vitals: BP 120/70 and HR 75. Lungs clear. EKG: STEMI in I, II, and aVF. Pt receives aspirin, alteplase, low-dose B-blocker, and one-time dose morphine. Several hrs later, pt is found comatose w/ asymmetric pupils and irregular breathing pattern. What was the cause of this pt's condition?

*Intracerebral Hemorrhage* *Fibrinolysis* via *Alteplase* binds fibrin and *converts plasminogen to plasmin* to restore blood flow. The most common SE of alteplase is *hemorrhage*. Signs of *ICH*: decreased consciousness, asymmetric pupils, and irregular RR. -to avoid these SEs, do *percutaneous coronary intervention* instead #823

21d old male has palpable swelling of neck. He feeds well but he is only comfortable when held sideways. Normal percentile for growth. Child favors looking toward the R and cries when his head it turned to the L. There is a firm swelling on the L side of his neck that does not move w/ swallowing. PE normal otherwise. What condition was most likely present prenatally?

*Intrauterine Malposition* Pt has *Congenital Tortcollis* which typically occurs b/c of birth trauma or malposition of head in utero. Both induce *SCM injury and fibrosis*. May also see blue foot, plagiocephaly, and facial asymmetry. #8325

Pt received an IV medication for recurrent syncopal episodes associated w/ palpitations and dizziness that's found to increase cardiac contractility and decrease vascular resistance. What was most likely given?

*Isoproterenol* A non-selective B-agonist that has *+ionotropy* (increased cardiac contractility) b/c of *B1 stimulation and vasodilation* (decreased vascular resistance) b/c of *B2 stimulation* -cannot use Esmolol b/c this is a selective B1 antagonist w/ --ionotropic effects #1836

23 yo male recently dx w/ HCM. What medication should be avoided to tx his angina?

*Isosorbide Dinitrate* Pts w/ *HCM* have dynamic *LV outflow tract obstruction* that worsens w/ decreased LV volume (associated w/ decreased preload or decreased systemic vascular resistance) so *vasodilators and diuretics* should be avoided in HCM pts *Vasodilators* (dyhydropyridine Ca+2 channel blockers, nitrates, and ACEi) decrease SVR, leading to decreased afterload and LV volume *Diuretics* decrease LV venous filling (preload) In contrast, *negative inotropic agents*--B-blockers (Metoprolol), non-dihydropyridine Ca+2 channel blockers (Verapamil), and Dysopyramide--*decreased LV outflow tract obstruction* and are helpful in HCM #141

Volume of distribution of a new drug is 4.5 L. The drug has what property?

*It is highly charged* *Total Body Water* is about 41 L. *ECF volume* is 1/3 of TBW (14 L). *Plasma volume* is about 3 L. *Interstitial volume* is about 11 L. *Highly charged drugs* (hydrophilic) tend to remain in the *plasma compartment* (3-5 L). -*large MW drugs*: highly bound to plasma proteins -*low MW and hydrophilic drugs*: can distribute to interstitial fluid compartments (14-16 L) -*low MW and uncharged/hydrophobic drugs*: goes to ALL compartments (41 L) #1710

RBC precursors are incubated in media containing radiolabeled cysteine. These cysteine residues are linked to appropriate tRNAs. The bound cysteine residues are chemically modified to form Alanine. End product is a tRNA containing cysteine anticodon but is mischarged w/ Alanine. What will most likely occur to this Alanine residue during polypeptide synthesis of alpha-Hb?

*It will be incorporated into the polypeptide chain at a site requiring cysteine* *Proof reading* in protein synthesis is associated w/ aa-tRNA synthetases #2032

Where would a lesion involving both CNs X and XI most likely be?

*Jugular Foramen* -also contains CN IX and Jugular V. -uvular deviation away from side of lesion #8522

Pt needs a coronary A. bypass via Great Saphenous V., this vein can be accessed from which site?

*Just inferolateral to the pubic tubercle* *Great Saphenous V.* runs superficially along medial foot-> anterior to medial malleolus -> up medial aspect of leg and thigh to join w/ femoral V. via saphenous opening at the cribriform fascia. *Femoral Triangle Boundaries*: -*Superior*: Inguinal lig. -*Lateral*: Sartorius m. -*Medial*: Adductor Longus m. #1967

A single nucleotide substitution induces an activating mutation, causing cancer. Which gene (APC, BRCA1, KRAS, RB, or TP53) is it most likely?

*KRAS* *Proto-oncogenes* stimulate cell proliferation and *activating mutations* lead to increased cell proliferation and neoplastic growth. ex: *KRAS* -the others are TSGs and loss of fx mutations (inactivation) leads to increased cell proliferation #1760

46yo male c/o intermittent, bloody diarrhea and abdominal pain for 1mo. Has lost 12lbs as well. Dxed w/ HIV 5yrs ago and is noncompliant w/ meds. Labs: CD4 50 and viral load 650,000. Colonoscopy: multiple hemorrhagic polyploidal lesions. Biopsy: spindle cells w/ surrounding blood vessel proliferation. Dx?

*Kaposi Sarcoma* -due to HHV8; can be reddish/violet maculopapular or raised hemorrhagic #8290

54 yo male w/ c/o severe fatigue and dyspnea. PMH: Hodgkin Lymphoma several yrs ago, which he received chest radiation. Now has long hx of treatment-resistant HF. He's hospitalized and continued to decline despite treatment. Dies 3d later. At autopsy, heart shows dense, thick fib rough tissue in the pericardial space. What sign would be detected on PE?

*Kussmaul Sign* Pt has *Constrictive Pericarditis*. The rigid pericardium restricts ventricular filling, decreasing CO, and causing R-sided HF. There's increased JVD. *Kussmaul sign* is the paradoxical increase in JVD seen w/ inspiration b/c RV cannot accommodate increased venous return. #98

68 yo female w/ sudden onset diplopia and it worsens when looking to the R. Hx of HTN, hyperlipidemia, and T2DM. BP 160/90. Eye exam is normal except the inability of L eye to accomplish Rightward gaze. Lesion is where?

*L. Dorsal Pons* Pt has *Internuclear Ophthalmoplegia*, a disorder of conjugate horizontal gaze due to damage to heavily myelinated fibers if *MLF*--mediated communication btwn CN III and CN VI. -Frontal eye feel project to contralateral PPRF->efferents to ipsilateral CN VI nucleus at facial colliculus in dorsal pons. -Subsequenctly, CN VI nucleus projects to ipsilateral LR muscle and contralateral MR via *MLF*. #12083

Why is there genetic instability w/ Hepatitis C Virus?

*Lack of 3'->5' exonuclease activity* *HCV* has a large amount of sub genotypes due to *hypervariable* genomic regions responsible for *envelope glycoproteins*. These are mainly generated by the *lack of 3'->5' exonuclease activity* in viral-encoded RNA Polymerase. #388

12yo male w/ mild intellectual disability brought for PE. Adoptive parents don't know fam hx, but he's otherwise doing well. Cytogenetic studies show a small gap near the tip of the long arm of the X chromosome. What would be seen on PE?

*Large ears, long face, and macroorchidism* *Fragile X Syndrome* is the most common inherited cause of intellectual disability and is due to *trinucleotide repeat expansion of CGG* found on the *long arm of chromosome X*. When cells are grown in *folate-deficient media*, the area of repeats *does not stain and appears "broken"* (small gaps). Earliest manifestation is motor and development delay. Classic features: *macrocephaly, long narrow face, macroorchidism, and prominent forehead, jaw, chin, and ears*. #344

24 yo G4P0 female experiences recurrent 2nd trimester pregnancy losses. Has menses every 28d w/ light bleeding for 2-3ds. PMH: L renal agenesis. Labs: anticardiolipin -- and lupus anticoagulant --. Hysterosalpingogram shows unfused uterine horns and there's abnormal contour to uterine fundus. What embryologic mechanism did not occur?

*Lateral fusion of the paramesonephric ducts* *Paramesonephric ducts* form Fallopian tubes, cervix, and upper vagina. Defects are closely associated w/ *renal anomalies. Incompletel lateral fusion* of paramesonephric ducts is associated w/ a *bicornate uterus* w/ an *indentation in the center of the fundus*. #1831

What muscle innervated by the thoracodorsal nerve is responsible for internal rotation of the arm?

*Latissimus Dorsi* -C 6-8 nerve roots #11679

72 yo male w/ stroke sxs. PMH: HTN and persistent A-fib. His anticoagulant was stopped 6 months ago b/c of GI bleeds. BP 160/80 and pulse irregular. CT w/o intracranial hemorrhage. Transthoracic Echo shows L. atrial enlargement, normal LV systolic fx, and mild mitral regurgitation. Sxs caused by thromboembolic event. What is the most likely source of thrombus?

*Left Atrial Appendage* *A-fib* is assoc. w/ increased risk of thromboembolic event. *L. atrial appendage* often found w/ mitral regurgitation b/c of increased atrial size and will be the sport for the thrombus formation. #11842

Pt undergoes pulmonary artery catheterization. Pulm A. is occluded by balloon and Pressure beyond point of occlusion is measured. The Pressure reading most likely corresponds to what other Pressure?

*Left Atrial Pressure* *Pulm. A. Occlusion P.* closely reflects *L atrial P.* and *LV end diastolic P.* #11780

64 yo male w/ T2DM c/o occasional dizziness. His sxs occur while playing tennis. Pt has no had loss of consciousness. 40 pack yr hx and drinks alcohol occasionally. Orthostatic vitals normal. EKG normal. Doppler US of L vertebral A. shows retrograde flow. What artery is most likely occluded based on these findings?

*Left Subclavian Artery* Pt has *Subclavian Steal Syndrome*, due to extreme *subclavian stenosis* proximal to origin of vertebral artery. The contralateral vertebral artery then shunts blood via connection as Basilar artery to the affected side's vertebral artery to supple the blood in the subclavian artery distribution. When sxs occur, they're related either to *arm ischemia* (exercise-induced fatigue, pain, and paresthesias) or *vertebrobasilar insufficiency* (dizziness, vertigo) #12046

77 yo male w/ severe midback pain, nausea, diaphoresis, and lightheadedness. PMH: HTN and CKD. Poor medication compliance. 40 yr smoker. TEE shows a dissection flap in descending aorta but none in ascending aorta. Dissection flap most likely originates where?

*Left Subclavian Artery* Pt has a *STanford Type B Aortic Dissection* (Descending) #12151

23 yo female w/ recent-onset diplopia. T2 hyper intensity consistent w/ axonal demyelination. Dx of MS. What neuronal property is most likely to decrease as a result of demyelination?

*Length constant* This is the measurement of how far along the axon an impulse can propagate. There is an increased charge dissipation along axon. #1318

An obese individual wants to get a gastric band that's placed around the cardiac part of the stomach. In order to encircle the stomach, the band must pass through what structure?

*Lesser Omentum* *Lesser Omentum* extends from liver to lesser curvature of stomach and beginning of duodenum. It's divided into 2 ligaments: *hepatogastric ligament* and *hepatoduodenal ligament.* Btwn the 2 layers of lesser momentum lie: hepatic A, common bile duct, portal V., lymphatics, and hepatic plexus #8587

3d old male c/o poor feeding, vomiting, and progressive lethargy. Diapers have a "burnt sugar odor." Normal pregnancy and delivery. Mother exclusively breastfeeds. Other 2 kids normal. PE: lethargic infant w/ dry mucous membranes and generalized hypertonia. What should be restricted from his diet?

*Leucine* Pt has *Maple Syrup Urine Disease*, and *AR disorder* due to a deficiency in *Branched Chain a-ketoacid dehydrogenase complex*. This normally breaks down *Leu, Ile, and Val* for TCA cycle. -*neurotoxic* b/c of increased *Leu* #1335

Middle aged male wakes up w/ severe knee pain, redness, and swelling. HE doesn't smoke but drank heavily the night before. PMH of PUD. Tx w/ oral Colchicine. What step does it inhibit?

*Leukocyte attraction -> inflammation* Pt has *gouty arthritis* induced by binge drinking. 1st line tx are NSAIDs (indomethacin) but that's contraindicated by PUD. *Colchicine* inhibits *microtubular polymerization*, preventing chemotaxis, phagocytosis, and degranulation. Also decreases formation of LTB4. -no effect on uric acid metabolism -do not admin to elderly pts w/ renal problems #858

72 yo male w/ 6 mo hx of back and thigh pain provoked by walking. He can walk further by being assisted w/ a stroller than w/o one. Also c/o occasional tingling sensation on LEs. No hx of trauma. PE: muscle strength normal w/o sensory findings. Peripheral pulses normal. Thickening of what ligament caused sxs?

*Ligamentum Flavum* Pt has *Spinal Stenosis*. This is *posture-dependent*: *lumbar flexion* relieves sxs -*lumbar extension* worsens sxs #12073

23 yo WF c/o acute optic neuritis. PMH: relapse-remitting MS. MRI: demyelinatization of L optic nerve. What is found on PE w/ light reflexes?

*Light in Right eye: Right and Left pupils constrict; Light in Left eye: no constriction bilaterally* The *Optic Nerve (CN II)* is the *afferent limb* of the pupillary light reflex pathway. Signals are transmitted to *superior colliculus*-> ipsilateral and contralateral *EW Nucleus* (start of *efferent limb*)-> ciliary ganglion-> oculomotor nerve (CN III)-> sphincter of iris #1735

Autopsy of 78 yo WM who died of esophageal cancer reveals a small heart w/o significant coronary artery atherosclerosis. Myocardial cells show prominent intracytoplasmic granules that are tinged yellow-brown. What accounts for microscopic findings?

*Lipid Peroxidation* Pt has *lipofuscin* inclusion that's normal "wear and tear". They're a product of free radical injury and lipid peroxidation. #300

16 yo female found unresponsive. Vitals: 103.5F, BP 70/40, and HR 130. There is diffuse petechial and ecchymotic skin rash. Labs: leukocytosis w/ L-shift and evidence of DIC and multi organ failure. Pt dies. Autopsy: hemorrhagic necrosis and bilateral adrenal gland destruction. What virulence factor allowed for such severity?

*Lipo-oligosaccharide* *Neisseria meningitidis* has an outer cell membrane VF called *LOS*, which is primarily responsible for disease severity. *Endotoxin* that acts on *TLR-4* on monocytes and dendritic cells to release *IL-1, IL-6, and TNF-a* #738

59 yo male w/ HTN, diabetes, and hypercholesterolemia comes in for f/u 3wks after new tx. No complaints. Labs: increase in K+ from 4.8 to 5.2 and serum Cr from 1.2 to 1.6. What new drug caused the change in pt's renal fx?

*Lisinopril* *ACEi* ("-pril") prevents efferent arteriolar constriction b/c of lack of Ang II, thus decreasing GFR #1148

"Moldy grains" in China cause a specific G-to-T mutation in gene p53. People in this region are at increased risk for what?

*Liver Cancer* *Aflatoxins*, from Aspergillus sp., are strongly associated w/ *Hepatocellular CA* #57

Pts w/ primary Hemochromatosis are at greatest risk of developing what?

*Liver cirrhosis and hepatocellular carcinoma* *Primary Hemochromatosis* is due to a mutation in *HFG protein*, which normally interacts w/ the *transferrin receptor* to sense Fe+2 levels. These mutations *inactivate HFE* causing RBCs and hepatocytes to *detect falsely low Fe+2 levels.* There's increased Fe+2 accumulation throughout the body via 2 mechanisms: 1) *Enterocytes* increase apical expression of *DMT1*, increasing GI Fe+2 absorption 2) *Hepatocytes decrease hepcidin synthesis*, causing increased basolateral ferroportin Fe+2 excess leads to: *micronodular cirrhosis*, DM, and skin bronzing. There's increased risk of *HCC* , CHF, and hypogonadism #395

Which organ (spleen, brain, kidney, liver, or Heart) would be least susceptible to infarction secondary to vasoocclusion?

*Liver* This has a *dual blood supply* (hepatic artery and portal vein). Portal venous and retrograde arterial flood from accessory vessels would sustain parenchyma -kidney and spleen have end-arterial blood supply and are susceptible to infarct #1875

3 yo male w/ 4d hx of high fever and malaise. Parents say he started to limp yesterday and will not bear wt on it. PMH--. 103F. Passive RoM does not illicit pain. No joint effusion. There increased focal radiotracer uptake where?

*Long Bone Metaphysis* Pt has *Hematogenous Osteomyelitis*, that primarily affects *metaphysis*. -adults are less likely to get osteomyelitis b/c of epiphyseal plate closure -*Sequestrum*: retained necrotic bone=> reservoir for infection -*Involverum*: poorly constructed shell of new bone #721

How would LV P/V loop be affected by Nitroprusside administration?

*Loop shrinks and shifts to the L. w/o shortening width* *Nitroprusside* is a balanced venous and arterial vasodilator. *Decreased preload* (decreased LV EDP) and *decreased afterload* (decreased MAP) w/o change in stroke volume #1652

What HIV medication would cause someone to have increased fasting glucose levels?

*Lopinavir* *Protease inhibitors* ("-navir") inhibit HIV polyprotein cleavage that normally forms mature virions. Adverse effects: 1) *Lipodystrophy*: buffalo hump w/ central obesity and peripheral wasting 2) *Hyperglycemia* 3) *P450 inhibitor* #819

Pt's glossopharyngeal nerve is accidentally transected in surgery. What sx is likely seen?

*Loss of general sensation at the tonsillar lining* *CN IX* originates at medulla and exits skull at the *jugular foramen* *Somatic motor*: stylopharyngeus m. (elevates larynx when swallowing) *Parasympathetic*: inferior salivary nucleus-> otic ganglion-> parotid gland *General sensory*: TM, Eustachian tube, posterior 1/3 tongue, tonsillar region, upper pharynx, and carotid body and sinus *Special sensory*: taste to posterior 1/3 tongue #1815

5 yo male w/ generalized edema following upper respiratory tract infection. PMH unremarkable. BP and HR normal. Serume Cr normal. Urinalysis: proteinuria w/o hematuria. Urine + for albumin. What pathologic changes are causing pt's urinary protein loss?

*Loss of glomerular basement membrane anions* Pt has *Minimal Change Disease*, which is common following an URTI in children. -caused by immune dysregulation -> overproduction of *glomerular permeability factor* (dmgs podocytes, causing effacement)-> decreasing anion properties of BM-> loss of -- charge-> *selective albuminuria* #385

Newborn female born to primigravida via an uncomplicated pregnancy w/ vitamins. PE: posterior neck mass and bilateral non pitting edema of the hands and feet. Femoral pulses diminished. Neck US: mass composed of cystic spaces separated by connective tissue. What underlying mechanism is responsible for this pt's condition?

*Loss of parental chromosome X* Pt has *Turner syndrome* w/ karyotype 45X0 pt's posterior neck mass is a *cystic hygroma*, bilateral extremity swelling from *lymphedema*, and *diminished femoral pulse* is suggestive of *coarctation of the aorta*. #339

56 yo female w/ 2-d hx of high fever, HA, confusion, and dry mouth. C/o abdominal discomfort and watery diarrhea. Cruise to Hawaii. 20 pack year smoker. 104F. Lung exam shows left lower crackles w/ no wheezing. Normal abdominal exam. CXR shows bilateral lower lobe interstitial infiltrates. What additional finding are present?

*Low serum sodium* (hyponatremia) *Legionella pneumonphila* is a community acquired pneumonia assoc. w/ the elderly, smokers, recent travel, and nursing home. -Labs: hyponatremia and Gram stain w/ PMNs w/ few/no microbes -Dx: culture BCYW and urine Ag tests #8257

22 yo male gets a penetrating R-sided stab wound just above clavicle, btwn the midclavicular and lateral sternal line. Course seems to be perpendicular w/ skin. Vitals: BP 88/60 and HR 114. What structure is injured?

*Lung Pleura* *Lung Apices* are found *above clavicle and first rib*. Pt would most likely have a *Tension Pneumothorax* w/ increased air accumulation w/in pleura=> increased pressure w/in chest cavity => decreased systemic venous return => decreased CO -sxs: tachycardia, hypoTN, tachypnea, hypoxemia, and absent breath sounds and hyper resonance on percussion of affected side. #1695

Researchers are assessing factors that effect vascular resistance. A catheter is measuring pressure and an oximeter for continuous recording of O2 saturation. The fraction of O2 inspired is gradually changed. A graph shows high vascular resistance w/ low O2 and low vascular resistance w/ high O2. What organ is this?

*Lungs* Lungs undergo a phenomenon called *hypoxic vasoconstriction* so that bloodflow can be diverted away from under ventilated regions and toward better ventilated regions for better gas exchange. -the relationship btwn hypoxia and vasoconstriction is reverse in systemic circulation -however, increased sympathetic tone does decrease splanchnic circulation #1587

8 mo old male w/ developmental delay, failure to thrive, and episodic seizures. PE: ophthalmoplegia and hypotonia. Labs: increased lactate. Studies show decreased pyruvate dehydrogenase activity. Increasing which aa will help generate energy w/o increasing lactate?

*Lysine* Pt has *PDH deficiency*, so he cannot convert *pyruvate to Acetyl-CoA*; there no link btwn glycolysis and TCA. Increased pyruvate->stimulates lactate dehydrogenase -> *lactic acidosis*. -pt should be on a *keotgenic diet* w/ high protein and low carb; *high Lys and Leu*; purely ketogenic amino acids are metabolized into a ketone body precursor for Acetyl-CoA, thus no extra lactic acid will be produced #998

CXR: round density w/ an air-fluid level in the lower lobe of the R lung. What is the most important contributor this lung lesion?

*Lysosomal content release by neutrophils* *Lung Abscess* is a necrotic infection of pulmonary parenchyma and often presents w/ *copious sputum and cavitation w/ air-fluid levels.* Tends to be b/c of aspiration of oropharyngeal bacteria. *PMNs* are key to forming lung abscesses. They're recruited and *release cytotoxic granules* containing myeloperoxidase. #302

45 yo male w/ c/o sudden-onset vomiting and severe abdominal pain that radiates to back. Labs: bilirubin 0.9, AST 98, ALT 32, alk phos 98, and serum lipase markedly elevated. Abdominal US: normal gallbladder and common bile duct. Dx: acute pancreatitis w/ specific etiology. What lab would show the specific underlying cause?

*MCV of 108 fL* *Alcohol-Related Pancreatitis* given *>2AST:ALT ratio* and *absence of gallstones*. While they're clinically indistinguishable, ARAP may present w/ *macrocytosis (MCV>100)* #434

45yo female c/o a generalize tonic-clonic seizure followed by post-ictal confusion. Pt has had mild daily HAs associated w/ nausea for 2yrs. HAs worse at night and often wake her up. Biopsy of intracranial mass shows psammoma bodies. Dx?

*Meningioma* *Meningiomas* are benign tumors of meningioepithelial cells of the arachnoid layer. Psammoma bodies are found in: meningiomas, mesothelioma, thyroid CA, and papillary serous CA. Meningiomas are typically found at the *falcine*, parasaggital, or lateral convexity of the brain. *Seizure* is b/c of compression of cerebral cortex #1151

4 yo male w/ c/o high fever, nasal discharge, and cough for 3d. Just returned from Mexico. PE: ill-appearing, febrile child. Pt has bilateral conjunctival injection and several small white spots w/ an erythematous base on buccal mucosa. No vaccines. Over the next several days, what is he likely to develop?

*Maculopapular Rash* *Measles Virus* (Rubeola) is an enveloped, --ssRNA virus of Paramyxoviridae. Transmitted airborne or person-to-person. *Classic Mealsure prodrome*: fever, cough, rhinorrhea, and conjunctivitis. *Koplik Spots* are pathognomonic. *Maculopapular Exanthem* that starts on *face* and spreads down to *trunk and extremities* occurs *later* (spares palms and soles) -could have been prevented w/ a *live, attenuated vaccine* -complications: encephalitis (w/in ds.), acute disseminated encephalomyelitis (w/in wks), and subacute sclerosing panencephalitis (w/in yrs) #1670

36 yo male c/o skin rash on his shoulders and upper chest. Rash began 2mos ago while at a beach resort. Rash has worsened progressively and is associated w/ mild pruritus, but no other sxs. Pt is a road construction worker in hot, humid areas. PMH: seasonal allergies and childhood asthma. Skin PE: hypopigmented macule on shoulder. Microbe?

*Malassezia globosa* *Pityriasis vesicolor* is characterized by hypopigmented, hyperpigmented, or erythematous macule on upper body. *Malassezia globosa* infection confines to *stratum corner* and is common in hot, humid areas w/ sun exposure. Dx via *KOH stain*. Morphology: *spores and hyphae*, producing *"spaghetti and meatball"* appearance. Hyphae have a *short, "cigar butt"* appearance. #104

Alcoholic found unconscious. Recovers over several days. Neurologic exam: short-term memory loss, nystagmus, ataxia, and ophthalmoplegia. What neural structure is damaged?

*Mammillary bodies* Pt has *Wernicke Encephalopathy*=> chronic alcoholism/malnutrition leading to *thiamine deficiency*. -thiamine is important in glucose metabolism b/c it is a coenzyme for *pyruvate dehydrogenase* #2129

Infant is born with Down syndrome. Southern Blot is conducted to look for etiology of the extra 21st chromosome. Southern Bloth shows child's DNA has 3 distinct 21 chromosome bands, where 2 overlap w/ mom and 1 overlaps with dad. When did the meiotic nondisjunction occur?

*Maternal Meiosis I* B/c the extra overlap did not coincide w/ the father's chromosomes, that means its *maternal nondisjunction*. B/c there are 3 distinct bands, that means it was *meiosis I nondisjunction*. This is due to *failure of homologous chromosomes* to separate. -answer is not "maternal meiosis II" b/c this would present w/ *2 bands where one band is larger than the other* #8328

An experiment where cells are lysed and all contents, except nucleic acids, are chemically removed. Cellular extract w/ purified nucleic acids are incubated along w/ short sequences of repeated deoxythymidine residues fixed to latex beads. What types of nucleic acid is most likely to bind the strongest?

*Mature mRNA* Experiement described the *poly-A tail on mature mRNA* b/c the Adenine will bind to the complementary deoxythymidine residues. #2033

23 yo female w/o seatbelt on gets in an MVA. PMH --. Meds --. A linear skull fracture at the junction of the frontal, temporal, parietal, and sphenoid bones is seen on head CT. A branch of which A. is severed?

*Maxillary* Pt suffered a fracture to the *Pterion* and lacerated her *Middle Meningeal A.* causing an *epidural hematoma*. MMA is a branch of the maxillary A., which enters the skull via *Foramen Spinosum* #1813

Med student is comparing blood glucose levels between mild and severe cases of acute pancreatitis. Prior to this, he conducts a descriptive analysis of the variable in each group. Blood glucose levels in pts w/ severe acute pancreatitis were found to have a strong positively skewed distribution. What is most likely true regarding the data?

*Mean>Median* *Positively skewed distribution*: increased number of observations w/ *larger than expected magnitudes* that shift curve to the *R* -*Mode<Median<Mean* #1282

3 yo male w/ small bowel obstruction undergoes laparotomy. During procedure, an incidental abdominal cyst is discovered and removed. The cyst is connected by a fibrous band to ileum and umbilicus. What condition is caused by the same embryo defect as the cyst?

*Meckel Diverticulum* *Vitelline Duct* connects midgut to yolk sac and is obliterated at wk 7. -there is partial closure of vitelline duct w/ paint ileum; fibrous band #322

56yo smoker w/ persistent dry cough c/o recent-onset HAs, dyspnea, and "having a puffy face" for 2wks. No shoulder pain. PE: symmetrical facial swelling and conjunctival edema. PERRL. Dilated vessels are seen over his neck and upper trunk. Heart sounds clear. Pt's condition is caused by what?

*Mediastinal Mass* *Superior Vena Cava Syndrome* is typically due to lung cancer or non-Hodgkin Lymphoma. Tumors obstruct SVC just below its fusion at the 1st costal cartilage on the R. Presentation is seen in vignette. May have increased ICP. #565

Chemotherapy pt experiences emesis. What brain structure is responsible for this?

*Medulla* Chemotherapy trigger zone is found on the *dorsal surface of the medulla at the caudal end of the 4th ventricle* (area postrema) #1741

14 yo male is incidentally found to have milder hypercalcemia. Further questions shows fam hx of mild hypercalcemia. Pt's PTH is mildly increased and urinary Ca+2 is very low. 25-hydroxyvitamin D is normal. A mutation in what receptor type is responsible for these labs?

*Membrane-bound receptor coupled with a G protein* *Ca+2-sensing receptors* are GPCR that regulate secretion of PTH. *Familial Hypocalcinuria Hypercalcemia* is an *AD Disorder* due to defective CaSR in parathyroid and kidneys #992

56 yo male recently dx w/ colon cancer has generalized edema. Urinary protein excretion is 4.5 g/24hr. Kidney biopsy shows glomerular capillary thickening w/o increased cellularity. Stained w/ silver methenamine shows irregular spikes protruding from GBM. Dx?

*Membranous Glomerulonephropathy* His nephrotic syndrome and *underlying malignancy* suggest *MG*, one of the most common adult nephrotic syndromes. -IF: *granular deposits containing IgG and C3* #382

61yo obese female c/o peripheral edema and proteinuria w/o other sxs. Serum IgG4 Abs to Phospholipase A2 Receptor (PLA2R), a transmembrane protein on podocytes +. Dx?

*Membranous Nephropathy* *Membranous Nephropathy* is the most common cause of Nephrotic Syndrome in *white people*. Its w/ primary disease are *PLA2R +*. Secondary disease is from drugs (NSAIDs, penicillin), infection (hepatitis), or SLE. May progress to CKD. EM: *spike and dome* appearance w/ *subepithelial deposits* #2131

17yo male c/o occasional hematuria. It began 1yr ago follow a flu-like illness that resolved spontaneously. He had another episode 6mos ago and it resolved. PMH:--. Fam hx:--. Pe:--. Vitals normal. Labs: BUN 14 and Cr 0.8. Urinalysis: protein 2+, trace blood, and some WBCs. Renal biopsy shows what?

*Mesangial Deposition of IgA* Pt has *IgA Nephropathy* (Berger Disease). It presents as *painless hematuria following URTI*. Renal Biopsy: *Mesangial hypercellularity and mesangial IgA deposition* -extra-renal involvement = Henoch-Schonlein Purpura #10

What germ layer is the spleen dx from?

*Mesoderm* #12198

What is detected when using rtPCR to dx CML?

*Messenger RNA transcript containing BCR and ABL axons* *rtPCR* works by using an *mRNA sample* to then generate *cDNA*, thus it would only contain *exons* since it is complementary to mRNA. -note: FISH would detect "chromosome position of the BCR and ABL genes" -note: Western Blot would detect "fusion protein containing BCR and ABL domains" #12278

43 yo male c/o nighttime dyspnea that awakens him. Sxs started 1yr ago following an URTI. PMH:--. Fam hx: brother w/ atopic dermatitis. Vitals: normal. PE: normal. PFTs: FEV1 88% (norm), FEV1/FVC 91% (norm), and DLCO 95% (norm). What medication would be good in diagnostic workup?

*Methacholine* PT's sxs and fam hx makes *asthma* a likely dx, despite his normal PFTS. *Methacholine* causes *brochoprovocation* and will induce asthma attacks and confirm dx. It is a *muscarinic agonist*, inducing bronchoconstriction, mucous production, and decreased FEV1. #1523

34yo previously healthy male presents to ER w/ 3hr hx of chest pain, diaphoresis, and dyspnea. PMH --. Fam hx: father died of MI at 56yo. Vitals: BP 110/70 and HR 110. PE--. EKG: ST elevation in anterior leads. Coronary angio: proximal LAD stenosis and thrombosis, which is treated. Labs: increased plasma homocysteine. Further testing shows homozygous mutation in methylene tetrahydrofolate reductase gene that leads to decreased enzymatic activity. Pt will have difficulty converting homocysteine to what?

*Methionine* *Increased homocysteine levels* is associated w/ *increased thrombotic events*, due to *endothelial damage*. Homocysteine can either be converted to *methionine* via remethylation of *cystathionine* via transsulfuration. Remethylation uses the enzyme *Methionine Synthase* and cofactors *B12* and Me-THF. In order to regenerate the Methyl, you need *methylene tetrahydrofolate reductase* and cofactor *FAD*. Thus a defect in MTHFR would cause increased accumulation of homocysteine and decreased methionine production #788

32 yo male pt w/ new holosystolic murmur best heard over cardiac apex recently dx w/ Endocarditis. Skin exam show nontender lesions on the sole of his feet. These lesions most likely represent what?

*Microemboli to skin vessels* Pt has *mitral regurgitation*, secondary to *Infective Endocarditis*. These are *Janeway Lesions*, described as non-tender, macular, and erythematous lesions on palm and soles. They are *septic emboli* from valvular vegetations. #72

What histopathologic findings are associated w/ HIV-associated dementia?

*Microglial Nodules* *HIV-associated Dementia* is characterized by progressive cognitive decline due to *subcortical dementia*, which involves *inflammatory activation of microglial cells*. *Microglial nodules* form around small areas of necrosis and may form multinucleate giant cells #11568

Ischemic Stroke >2wks later

*Microscopic changes*: glial scar formation *Macroscopic changes*: cystic area w/ dense glial fibers

Ischemic Stroke 1-2 wks later

*Microscopic changes*: reactive gloss and vascular proliferation around necrosis *Macroscopic changes*: liquefactive necrosis (1wk-1mo)

6yo in ER w/ confusion and intractable vomiting. Sxs began a few hrs ago and have been worsening. Mom says younger brother gave him an illness a few ds ago and she's been giving "OTC pills" for fever. Boy becomes comatose. LM of liver shows what?

*Microvesicular Steatosis* Pt has *Reye Syndrome* from being treated w/ *Aspirin* during a viral illness (most common in children btwn 5-14 yo). *Hepatic dysfx*: vomiting and hepatomegaly; increased ALT, AST, ammonia, bilirubin, PT, and PTT; LM: *microvesicular steatosis*; EM: *swelling and decreased mitochondria and glycogen* #881

65 yo male found unresponsive at home in pulseless V-fib. Paramedics take 10 minutes of CPR to receive spontaneous circulation. Medically-induced coma is achieved. Upon attempt to bring him out, he remains comatose w/ fixed and dilated pupils w/o direct or consensual light reflex. MRI: diffuse loss of grey-white matter. What area of the brain is responsible for pupillary findings?

*Midbrain* *Normal pupillary reflex*: retina and *optic nerve*-> upper midbrain-> *pretectal nucleus*-> bilateral *EW nuclei*-> preganglionic parasympathetic via *CN III*-> ciliary ganglion -> postganglionic parasympathetic -> sphincter muscle #12119

Mature RBCs are unable to synthesize heme, despite containing the necessary enzymes in their cytoplasm. Lack of which organelle is the reason?

*Mitochondria* *Heme synthesis* occurs in/around the *mitochondria*. It begins and ends here. -1st step: Succinyl-CoA + ALA Synthase-> ALA -Final step: Protoporphyrin IX+Fe+2-> Heme #1455

What would indicate irreversible cell injury?

*Mitochondrial Vacuolization* -also could see: rupture of lysosomes, plasma membrane damage, increased mitochondrial permeability, and nuclear condensation, fragmentation, or fading -disaggregation of nuclear granules is NOT irreversible #176

HCM sxs are most likely explained by LVOT obstruction created by what 2 structures?

*Mitral valve leaflet and interventricular septum* -anterior mitral valve leaflet shifts towards aortic valve -IVS moves in front of aortic valve #76

34 yo female c/ c/o 1wk hx of mood swings, difficulty concentrating, and hand tremor. She has associated it w/ pain in front of her neck. Pain radiates to ears and worsens w/ swallowing. Pt originally attributed sxs to flu-like illness a few wks ago. Vitals: BP 140/80 and HR 105. Thyroid is very tender to palpation. Thyroid scan shows diffuse decrease in radioactive iodine uptake. ESR 105. What pathologic changes occurred in pt's thyroid?

*Mixed, cellular infiltration with occasional mulinucleated giant cells* Pt has *Subacute Granulomatous Thyroiditis (de Quarvian Thyroiditis)*. It typically follows an *acute viral illness* and is thought to be due to a cross reaction of immune response. Pt will have transient hyperthyroidism, but will later move to hypothyroidism. This is self-limited and resolves in <6wks. #768

Charcot-Bouchard Aneurysm

Due to chronic HTN Involves lacunar arteries Rupture causes intraparenchymal hemorrhage Acute

34 yo male c/o severe HA and blurry vision. Sxs began after eating at a new Italian Deli, where he ate "fancy meats and cheeses" and drank iced tea. PMH: severe, atypical depression. Vitals: BP 210/130 and HR 110. PE: tremulous and diaphoretic. The medication used to treat this man affects what step of monoamine neurotransmission?

*Monoamine Degredation* Pt is in a *Tyramine-Hypertensive Crisis* due to the concurrent ingestion of *Tyramine-containing foods* (aged-cheese, meats, and beer) and *MAOis* (Tranylcypromine and Phenelzine). These drugs also inhibit degradation of dietary tyramine, allowing it to enter the systemic circulation and cause severe HTN and other signs of sympathetic hyperactivation. #572

51 yo female c/o constipation, wt gain, and fatiguability. Sxs started 6mos ago and have worsened. PMH: --. Vitals: BP 110/70 and HR 55. PE: diffuse, mild enlargement of thyroid. Rest of PE--. What would thyroid biopsy show?

*Mononuclear parenchymal infiltration with well-developed germinal centers* Pt has *Hashimoto Thyroiditis*, the most common cause of hypothyroidism in the US -this is not Reidel Thyroiditis b/c the thyroid would have been rock-hard #769

44 yo male w/ c/o low mood, impaired concentration, increased sleep, and appetite, feelings of heaviness in arms and legs, and loss of energy. Has had difficulty at work b/c of being overly sensitive to criticism. Despite his boss' complements, he is worried that his job is in jeopardy. Sxs started 8mos ago w/o trigger. He hasn't had luck w/ 3 different anti-depressants and declines ECT. Doc considers Phenelzine. Presence of what other sxs would make this medication appropriate?

*Mood Reactivity* Pt has *Atypical Depression* characterized by *mood reactivity, leaden paralysis, rejection sensitivity, and increased sleep and appetite*. Mood reactivity (feeling better in response to positive events) is key. *MAOis* (Phenelzine, Tranylcypromine, Selegiline) are typically only used to treat *Atypical Depression* and *Treatment-resistant Depression* b/c of severe SEs of hypertensive crisis and Serotonin Syndrome #573

What is the most rare cause of Down Syndrome

*Mosaicism* -nondisjunction during mitosis -recurrence risk is similar to normal population #1610

46 yo female alcoholic has not consumed alcohol in 4wks and is motivated to remain abstinent. She wants to decrease cravings. What MoA is most effective?

*Mu-opioid receptor blockade* *Naltrexone blocks mu-opioid receptors* and can be used while pt is still drinking It (blocks the reward pathway* and decreases cravings -cannot use Disulfiram in actively drinking pts and does not decrease cravings -Acamprosate is used once abstinent as well as binds NMDA receptors #11577

4yo male c/o decreased appetite, abdominal cramps, and diarrhea for 3ds. Stools started watery and became bloody. 100.4F. Signs of dehydration and mildly distended abdomen w/ diffuse pain elicited by palpation. Cultures: non-lactose fermenting G-- rods on MacConkey agar. Bacteria ferments glucose w/o gas or H2S production. Cannot grow in refrigeration. What bacteria factor is most important for pathogenesis?

*Mucosal Invasion* Pt is infected w/ *Shigella sp.* They are non-motile and do not produce H2S (contrast w/ Salmonella sp.). *Mucosal invasion* is essential for pathogenesis of Shigella sp. via M cells that overlay Peyer's Patches. Shigella sp. can then move from cell-to-cell via *actin polymerization* and induce *dysentery* -note: Shigella sp. pathogenesis does not require/rely on toxin production #1135

An outbreak of water-borne gastroenteritis reported in Latin America is caused by oxidase +, G--, comma-shape rods that can survive on alkaline media. Stool microscopy demonstrates what?

*Mucous and some sloughed epithelial cells* *Vibrio cholerae* is a non-invasive bacteria that produces *Cholera Toxin* to activate adenylate cyclase, increase cAMP, and increase Cl- excretion into lumen (similar to ETEC heat labile toxin). This induces *"rice-water stools"* (watery diarrhea) w/ mucous and epithelial cells #976

Pubescent female w/ amenorrhea and normal BMI has fully developed secondary sexual characteristics, shortened vaginal canal, and rudimentary uterus. Dx?

*Mullerian Aplasia* Mullerian ducts give rise to Fallopian tubes, uterus, cervix, and upper vagina. -pts have normal ovaries -may have *renal agenesis* #1809

A pt w/ Ulcerative Colitis is concerned about her risk for colorectal cancer. Compared to the general population, colorectal malignancy arising w/ her will exhibit what feature?

*Multifocal Origin* *IBD* pts have a 30% increased risk of colorectal cancer. They happen *younger* (40-55yo), originate as *flat* (nonpolyploidal) lesions, *proximal*>distal, multifocal, *mucinous &/or signet* ring cells, *poorly differentiated* (high grade), *early p53* mutation, and *late APC* mutation -opposite of above is found in sporadic cases #411

Elderly pt comes in w/ shingles rash on chest. What pathologic finding is most likely in the effected area?

*Multinucleated cells w/ intranuclear inclusions* -*+Tzanck smear* -skin biopsy: acantholysis of keratinocytes and intraepidermal vesicles #1042

24 yo male dx w/ schizophrenia and started on Chlorprozamine. Stopped taking it b/d he didn't like how it made him feel. He's changed to Fluphenazine. Compared to initial tx, Fluphenazine will most likely cause what?

*Muscular Rigidity* *First Gen Antipsychotics* are classified based on *potency*. *Low Potency FGAs (Chlorpromazine and Thioridazine)* cause *non-neurologic SEs* associated w/ *histamine, cholinergic, and NE blockade* (sedation and orthostatic hypoTN) *High Potency FGAs (Haloperidol and Fluphenazine)* cause *neurologic SEs* or *EPS* due to potent *D2 antagonism* of *nigrostriatal pathway* -Drug-Induced Parkinsonism #515

A woman taking Valproate and Labetalol wants to conceive. If she conceives now, what will most likely develop in her offspring?

*Myelomeningiocele* *Valproate* is contraindicated in pregnancy b/c it increases risk of neural tube defect due to interference w/ folate metabolism -switch pt to Levetiracetam #507

44 yo male w/ c/o 3d hx of fever, chills, malaise, dyspnea, and productive cough of "green sputum." PMH-- and never been hospitalized. 25 pack hx of smoking. PE and CXR are indicative of pneumonia. What made this pt's sputum green?

*Myeloperoxidase* A relatively healthy individual w/o hospitalization and dense lobar infiltrate likely has *Community Acquired Pneumonia*, which is primarily *Streptococcus pneumoniae*. Tobacco use increased risk. PMN *myeloperoxidase* is responsible for *green sputum* b/c it is a blue-green pigment -pt does not have P. aeruginosa b/c is it not a common CAP in healthy adults #1910

A pt dx w/ acute MI complicated by acute severe HF is started on an IV Dobutamine infusion. What is most likely increased in this pt?

*Myocardial Oxygen Consumption* *Dobutamine* is a *B1 agonist* (weak B2>>a1) and is used in management of refractory HF w/ LV diastolic dysfx and cariogenic shock. B stimulation increases cAMP to do: 1) *positive ionotropy and chronotropy*: increased contractility and HR=> increased CO (helps end-organ perfusion) and decreased LV filling pressure (helps pulmonary edema) 2) *mild vasodilation*: decreased SVR=> decreased BP--helps avoid increased after load The *strong ionotropy* of dobutamine is what *increases myocardial O2 consumption*, which may worsen myocardial ischemia, but the increase in CO make up for it -do not give to decompensated HF #1344

53 yo male c/o SOB and chest tightness. Hx of HTN but is noncompliant. Vitals: BP 195/115 and HR 90. Lungs reveal bibasilar crackles. Nitroglycerin infusion provides symptomatic relief. Repeat BP 165/90. What intracellular events is responsible for beneficial effects of pt's tx?

*Myosin Dephosphorylation* Pt is in *Hypertensive Emergency* and IV Nitroglycerides (vasodilators) improve acute HF by *decreasing preload and after load* -*Nitrates*-> vascular smooth muscle-> *activate guanylate cyclase*-> increase cGMP-> *decreased intracellular Ca+2*-> *activates myosin light chain phosphorylase*-> promotes *myosin light chain dephosphorylase*-> vascular smooth muscle dilation #136

21 yo WM suffers from weakness and gait disturbance. He has had difficulty releasing the doorknob lately. PE: cataracts, frontal baldness, and gonadal atrophy. Biopsy: loss of mostly type 1 muscle fibers. Pt's condition is described as what?

*Myotonic Dystrophy* Abnormally slow relaxation of muscles is called *myotonia*. *Myotonic Dystrophy* is an *AD trait* due to an abnormal trinucleotide repeat *CTG* that encodes *myotonia-protein kinase*. Vignette has other characteristics. -Unlike DMD, necrosis of muscle fibers and fibrofatty replacement are NOT common in myotonic dystrophy #1268

2 yo male found to have Ehlers-Danlos Syndrome. A skin biopsy shows a defect in extracellular processing of collagen. What step in collagen synthesis is impaired?

*N-terminal propeptide removal* *Ehlers-Danlos Syndrome* is due to a deficiency in *procollagen peptidase*, the enzyme that *cleaves terminal propeptides from procollagen* in the extracellular space. Impaired propeptide removal forms a soluble collagen that does not properly crosslink, causing *joint laxity, hyperextensible skin, fragile tissue, and poor wound healing* #1245

What mutation and chromosome is associated w/ Bilateral Acoustic Schwannomas?

*NF2 on chromosome 22* *NF2* is an *AD* disorder w/ a mutation in *merlin* #1305

30yo female w/ TDM c/o anorexia, wt loss, and decreased insulin dependence. PE: generalized hyperpigmentation. ACTH stimulation test fails to illicit increased cortisol. What would the lab values be for this pt? (Na+, K+, Cl-, and HCO3-)

*Na+ decreased; K+ increased; Cl- decreased; HCO3- decreased* Pt's T1DM predisposed her to *Addison's disease* (Primary Adrenal Insufficiency), which is why *exogenous ACTH did not increase cortisol*. Lack of cortisol negative feedback caused increased POMC production, causing *hyperpigmentation*. The *lack of aldosterone* put her into a *hypoNa+, hyperK+, hyperCl-, non-anion gap metabolic acidotic state* #924

23yo male falls asleep when talking to people and frequently snores. He almost always naps in the afternoon and feels refreshed afterwards. He states that sometimes he hears a voice calling his name prior to falling asleep. Also states a few episodes of clumsiness. Dx?

*Narcolepsy* *Narcolepsy* is characterized by the frequent overwhelming urge to sleep. Its associated w/ *cataplexy*, sudden hypotonia in response to + emotions. Will see *low hypocretin-1* from lateral hypothalamic neurons. Will see shortened REM latency. May c/o *hypnagogic* (upon sleep) or *hypnopomic hallucinations* (upon waking) #1458

6 yo male w/ persistent epistaxis due to persistent nose picking. Fam hx -- for bleeding disorders. No meds. Silver nitrate cautery is performed and bleeding stops. Where was cautery place in nasal cavity?

*Nasal Septum* *Anterior Epistaxis* is the most common form of nose bleeding and most commonly occurs w/in *nasal septum* b/c of *Kiesselbach Plexus*. *Anastamoses here*: -Septal branch of *anterior ethmoidal A.* -lateral nasal branch of *sphenopalatine A.* -septal branch of *superior labial A.* (from facial A.) #11783

55yo male c/o intermittent abdominal pain. Takes occasional OTC NSAIDs for osteoarthritis. Tobacco and alcohol --. Fam hx:--. Works at a busy airport as an air traffic controller. Upper GI endoscopy: ulcer in distal duodenum. Fasting gastrin at upper limit of normal and increases w/ administration of IV secretin. Condition is b/c of what?

*Neoplasm* The distal duodenal ulcer and gastrin level and response to secretin makes *Z-E Syndrome* likely. Pt has a *gastrinoma* in pancreas or small intestine. Increased gastrin causes: parietal cell hyperplasia, *peptic ulcers*, heartburn, and *diarrhea* (impaired pancreatic enzymes due to low pH). -*Secretin* normall inhibits gastrin secretion; however, it *paradoxically increases* gastrin secretion in *Z-E Syndrome* -Secretin decreases gastrin secretion in *hypergastrinemia* (atrophic gastritis) -H. pylori and NSAIDs cause proximal duodenal ulcers #305

76 yo male c/o 2mo hx of progressive lower back pain. Pain is constant and nagging and is not relieved by rest. It interferes w/ sleep at night. NSAIDs/analgesics do not relieve sxs. PMH: HTN and osteoarthritis of knees and hands. Admits to IVDU in 30s. What pathologic process if responsible for back pain?

*Neoplastic* *Spinal Metasteses* features: advanced age, pain that is *worse at night*, and persistent even w/ analgesics. Bony metastases locations: breast, kidney, thyroid, and lung #341

59yo male c/o several hrs of diplopia. PMH: long-standing Diabetes w/ poor glycemic control, osteoarthritis, and PUD. PE: R-sided ptosis w/ R pupil in inferolateral position. PERRL. Condition is due to what etiology?

*Nerve Ischemia* *Diabetic Ophthalmoplegia* in CN III is due to *ischemia nerve damage* involving the core of CN III w/ *sparring of superficial parasympathetics* (this allows for PERRL) #1060

Biopsy of small cell lung cancer would most likely stain + for what histopathology?

*Neural Cell Adhesion Molecule* *Small cell CA of the lung* is the most *aggressive* type of lung cancer. They're associated w/ SIADH. These tumors are + for *neuroendocrine markers* such as: *neural cell adhesion molecule* (CD 56), neuron-specific *enolase, chromogranin*, and synaptophysin. Some express *neurofilaments*. #650

11mo male c/o irregular jerking movements. He's had 2wks of looking pale and tired and has been more fussy and less playful than usual. Vitals: 98F, BP 100/60, HR 114, and RR 16. PE: spontaneous bursts of nonrhythmic conjugate eye movements in various directions. Pt also has myoclonus in trunk and extremities as well as generalized hypotonia. A R-sided, nontender, abdominal mass is palpated. No HSM. CBC: anemia. Urine + for catecholamine metabolites. Dx?

*Neuroblastoma* *Neuroblastoma* heavily presents in *children* w/ *opsoclonus-myoclonus syndrome* (eye movements and myoclonus described in vignette). Arises from *neural crest cells* of adrenal medulla or sympathetic ganglia. Typically <2yo. May see *anemia/pancytopenia* and *periorbital ecchymoses*. *Increased catecholamines* b/c of neural crest origin. Biopsy: *small round blue cells and Homer Wright rosettes*. IHC: *N-myc* #1263

31yo female w/ new-onset generalized tonic-clonic seizures has an intracranial mass that stains + for synaptophysin and -- for glial fibrillary acidic protein. Neoplastic cells originate from the same precursor as what?

*Neurons* *Synaptophysin* is a TM glycoprotein found on presynaptic vesicles of *neurons*, neuroectodermal, and neuroendocrine cells #880

55 yo male goes to ER w/ c/o CAD sxs. PMH: asthma, HTN, and diabetes. Smokes heavily. Initial Vitals: BP 160/100 and HR 100. Administered tx and chest pain goes away, but becomes SOB. New Vitals: BP 135/85 and HR 65. PE: prolonged expiration and bilateral wheezes. Impairment of what at the synapse cause this pt's SOB?

*Neurotransmitter-receptor interaction in adrenergic synapses* Pt has *Atherosclerotic CAD*, as seen w/ PMH, lifestyle, and sxs. Initial tx was a *B-blocker*, which treated tachycardia and chest pain, but induced an *asthma exacerbation*. This is seen when you administer a B-blocker to a pt w/ asthma or COPD #2000

43yo WM found to have recent-onset oliguria and increased serum Cr. He's had several nasal ulcers that fail to heal. He has autoAbs to what?

*Neutrophils* *Wegner's* presents w/ *nasal ulceration and glomerulonephritis* w/o pulmonary involvement. *c-ANCA +* (PMNs) #459

56 yo male has acute gouty arthritis. PMH: mixed hyperlipidemia. What medication precipitated his gout?

*Niacin* *Niacin* improves hyperlipidemia by *decreasing hepatic synthesis of VLDL* and *decreasing HDL clearance*. Its the most effective at *increasing serum HDL*. Niacin can *decrease renal excretion of uric acid* and *increase risk of acute gouty arthritis.* Other SEs: flushing, hyperglycemia, and hepatotoxicity #167

12 yo male w/ c/o gait instability and pruritic skin rash for several wks. He's been irritable and had loose stools. Child development normal, except several episodes of skin rash that resolved spontaneously. PE: scaly, erythematous skin lesions in sun exposed areas and cerebral ataxia. Labs: increased levels of neutral aas in urine. Sxs would improve w/ what supplement?

*Niacin* Pt has *Hartnup Disease*, an *AR disorder* w/ a defect in *neutral aa transporter*, especially Trp, in the small intestine and PCT. *Trp* is an essential aa for *niacin, serotonin, and melatonin synthesis*. Conversion of *Trp->Niacin* is responsible for >50% generation of *NAD+*. Pt presents w/ pellagra-like skin eruptions and cerebral ataxia -tx: Niacin and NAD+ and supplementation #1334

A new partial agonist/antagonist against receptor X is applied to cells and there is immediate change in transmembrane Ca+2, Na+, and K+ flow secondary to the opening of the R. channel. Receptor X is most likely what type of R.?

*Nicotinic Cholinergic Receptor* The key to this question is *immediate* flux of ions -Na+ and Ca+2 influx -K+ effluxes #1360

Vesicoureteral Junction

*Non*obstructive fetal hydronephrosis

A sickle cell pt is experiencing an aplastic crisis. What is the structure of the casual organism?

*Nonenveloped ssDNA* -Parvovirus B19 #1496

75yo male found unresponsive. PMH: poorly controlled HTN. Vitals: BP 240/120 and HR 104. PE: extensor posturing and pinpoint pupils. Head CT: acute pontine hemorrhage w/ mass effect. Pt dies hrs later. Autopsy: disruption of all pigmented neurons in the posterior rostral pons and lateral floor of 4th ventricle. These neurons normally produce what?

*Norepinephrine* Pt had hypertensive pontine hemorrhage at *locus ceruleus*, a brainstem nucleus found in the *rostral pons near the lateral floor of the 4th ventricle*. Locus ceruleus secretes *NE*. This area also controls: mood, *arousal*, sleep-awake states, cognition, and autonomic fx -pt's PE is due to disruption of *reticular activating system* -abnormal activation of locus ceruleus = anxiety disorders #12226

34 yo female w/ c/o generalized weakness and paresthesias. PMH--. Meds--. BP 150/95. Cardiac and PV PE normal. Labs: decreased renin and normal serum Cr. CT of abdomen shows solitary, hypodense 1.5 cm R. adrenal mass. What serum electrolyte pattern is seen? (Na+, K+, and HCO3-)

*Normal Na+; Decreased K+; Increased HCO3-* *Hyperaldosteronism* (primary mineralocorticoid excess) is suggested in *young pts w/ HTN* (suggest secondary cause), weakness, paresthesias (acid-base disorder), and *decreased renin*. This pt has *Conn Syndrome* from adrenal adenoma. Hyperaldosteronism has *increased Na+ reabsorption* from CD. This creates a --lumen, *pulling K+ and H+* into urinary excretion, causing *hypoK+*. This loss of H+ stimulates *HCO3-/Cl- exchanger*, resulting in *metabolic alkalosis* (increased production of HCO3-). -you don't see increased Na+ absorption, hyperNa+, and edema w/ hyperaldosteronism b/c of *ANP/BNP* detect the increased vascular volume and limits Na+ retention #929

64 yo female w/ hx of close TBI c/o progressive gait disturbance for 2yrs. Also has difficulty concentrating, forgetfulness, and lack of interest in daily activities for 12 mos. 6wk hx of urinary urge incontinence. Mini-Mental Status Exam score of 20/30 w/ poor performance in executive fx. PE: increased tone and hyerreflexia of lower extremities along w/ slow gait and decreased step ht. Head CT shows ventriculomegaly w/o sulk enlargement. Dx?

*Normal-Pressure Hydrocephalus* Pt's *NPH* is b/c of *decreased CSF reabsorption by arachnoid granulations* (aka: Communicating Hydrocephalus) -sxs are *progressive* and due to disruption of periventricular white matter -normal ICP -urinary incontinence is a late sx -dx made by sxs going away after spinal tap/CSF removal #16

52 yo male dx w/ asymptomatic heart murmur 3yrs ago noticed he gets fatigued easier now. Vitals: BP 145/90 and HR 80. PE: holosystolic murmur best heart at apex that radiates to axilla. What is the best indicator of severity of pt's disease?

*Presence of audible S3* Pt's murmur findings is consistent w/ *Mitral Regurgitation*, allowing for retrograde blood flow from LV->LA in diastole. This increase in LA pressure/volume causes increased blood re-entering into LW during diastole=> *audible S3 gallop* (cannot accommodate excess blood flow). #944

A mutant Candida sp. is found to have an altered gene involving ergosterols. This species has enhanced growth in the presence of drug X. The MOA of drug X is via a decrease in ergosterol incorporation into the cell membrane. Drug X is what?

*Nystatin* *Polyenes* (Nystatin and Amp B) fx by *binding ergosterol* molecules in the cell membrane, *creating pores* and lysis. They *depend on the amount of ergosterol* incorporation into cell membranes for *efficacy*. Pores induce loss of ions, esp K+, and loss of cell membrane integrity causes lysis. Resistance: decreased amount of ergosterol in cell membrane #271

Asthmatic kid comes in w/ white plaques on tongue. How to tx?

*Nystatin* Pt has *Oropharyngeal Candidiasis* due to inhaled corticosteroid. *Nystatin* binds ergosterols causing pores and leakage of cell contents. -not absorbed in GI tract -"swish and swallow" -Amp B is for systemic use only; not topical #1195

65 yo female is concerned about osteoporotic hip fracture. PMH: HTN, hyperlipidemia, CAD, seizure disorder, and GERD. Underwent menopause at 52yo. Long-term use of what medication increases risk of osteoporotic hip fracture?

*Omeprazole* *Insoluble Ca+2* requires acidic environment to be absorbed and *PPIs* (Omeprazole) will *decrease Ca+2 absorption* and increase risk of osteoporotic fractures #10930

Researchers assess sugar metabolism in WT vs mutant E. coli. Both grow on lactose-containing media. Growth is then assessed on media w/ only glucose and colonies from here undergo Western Blot w/ fluorescent probe for B-galactosidase. WT has little expression. Mutant expresses a significant amount of B-galactosidase. Further analysis shows that mutants have mutation that inhibits binding of a certain protein to is regulatory sequence. What location did this mutation occur?

*Operator Locus* *Repressor proteins* are constitutively expressed to inhibit gene expression by binding the *operator locus* -note: lac operon is *positively* regulated by *cAMP-CAP* binding *upstream of promoter* #1479

62 yo female w/ c/o decreased vision. Had 6wk hx of progressive difficulty seeing objects on her R. side. Also c/o intermittent HAs that are worse in the morning. PE: R. homonymous hemianopia. Light in L. eye causes bilateral pupil constriction; light in R. eye appears to dilated pupils. Pt's sxs are due to a L-sided lesion where?

*Optic Tract* *Optic Tract Lesions* cause *contralateral homonymous hemianopia*. Its may experience *afferent pupillary defect* in pupil contralateral to lesion--"appears to dilate" #8595

34 yo immigrant from Eastern Europe c/o 3mo hx of productive cough, night sweats, and low grade fever. Sputum cultures grow yeast that forms germ tubes at 37C. Most likely site of organism was prior to entering sputum was?

*Oral Cavity* Pt is colonized by *Candida albicans*. In *tissue section* they have *single cells w/ pseduohyphae*. Pt has TB but Candida albicans in sputum indicated that only oral cavity is colonized #119

52 yo male w/ slowly enlarging, painless mass in his R groin. PE: several enlarged, hard LNs are palpated in the R inguinal area inferior to inguinal ligament. Excisional biopsy shows malignant cells. These cells most likely originate from where?

*Orifice of anal canal* Pt has palpable *Superficial Inguinal LNs*, which drains *most cutaneous lymph from umbilicus down*, including external genitalia and anus (below dentate line) -*Exceptions*: glans penis and posterior calf go to deep inguinal LNs #1631

A pt w/ congenital deficiency in dopamine B-hydroxylase will most likely develop what?

*Orthostatic Hypotension* These pts cannot convert *Dopamine -> NE*, and subsequently cannot synthesize Epi. This disorder is characterized by impaired *sympathetic adrenergic activities*, w/ normal cholinergic and parasympathetic fx -*Infantile presentation*: hypoTN, ptosis, and hypothermia -*Adult presentation*: orthostatic hypoTN, exercise intolerance, nasal congestion, and retrograde ejaculation #6695

23yo WM c/o recurrent severe nosebleeds and pink spider-like lesions on his oral and nasal mucosa, face, and arms. What does he suffer from?

*Osler-Weber-Rendu Syndrome* *AD* inheritance of *congenital telangiectasias of skin and mucous membranes* #469

70 yo male w/ c/o intermittent leg pain and difficulty walking. Hx of osteoarthritis in hands, so he takes NSAIDs, but it has never affected his knees. PE: point tenderness over R tibia. Labs: increased alkaline phosphatase. Bone biopsy: haphazardly oriented segments of lamellar bone w/ prominent cement lines. Initial phase of pt's disorder is due to increased activity in what cells?

*Osteoclasts* Pt has *Paget's disease of the Bone*, per epidemiology, alk phos, and bone biopsy. There is *excess RANK and NF-kB activation*, causing increased osteoclast activity. 3 phases: 1)*Osteolytic*: increased osteoclast and resorption 2)*Mixed*: rapid bone formation and destruction 3)*Osteosclerotic*: increased osteoblast actin where mosaic pattern forms #987

Osteogenesis imperfecta is due to impairment of what process?

*Osteoid production by osteoblasts* #702

Other than Rb, what cancer is a child at risk of receiving w/ this mutation?

*Osteosarcoma* -Rb is a *TSG on chromosome 13* that is associated w/ Retinoblastoma and Sarcomas -active (dephosphorylated) Rb normally inhibits G1->S phase progression #863

48 yo female c/o muscle weakness. Sxs have progressed in past 3mos. She c/o difficult w/ climbing stairs, getting out of chairs, and placing dishes in overhead cabinets. Reports 10 lb wt loss, subjective fevers, and occasional abdominal discomfort. PMH: GERD and hypothyroidism, for which she's on appropriate meds. PE: weakness of shoulder and hip girdle muscles. There are also erythematous plaques on hands and joints. Further evaluation shows she has what condition?

*Ovarian Adenocarcinoma* *Dermatomyositis* is a systemic autoimmune disease characterized by *proximal muscle weakness* resembling Polymyosistis, but w/ additional skin inflammatory sxs. Unique features: *heliotrope rash* in periorbital area and cheeks along w/ *Gottron's Papules*, which are erythematous plaques found on joints of hand. Biopsy: *perimysial inflammation and atrophy w/ CD4 T cells*. May occur alone or *paraneoplastic* (ovarian, lung, colorectal, or non-Hodgkin) -pts may be sero+ for: *anti-Jo-1, anti-SRP, or anti-Mi2 Abs* #11805

67 yo WM w/ PMH of treatment-resistant HTN dies of inter cranial hemorrhage. Autopsy: small R kidney and grossly normal L kidney. What mechanism explains renal morphology?

*Oxygen and nutrient deprivation* Pt has *Unilateral Renal A Stenosis*, which is most commonly due to an atheromatous plaque at origin of renal A. Associated w/: males. DM, and increased age. Histology: crowded glomeruli and tubulointerstitial atrophy and fibrosis #453

34 yo male c/o frequent clumsiness. 6 mo hx of recurring minor injuries, such as walking into stationary objects and bumping into coworkers. PMH: recurrent renal stones and had to get surgical tx for them. Unknown fam hx b/c he's adopted. PE: bitemporal visual field defects. Neural PE is otherwise normal. In addition to brain imaging, what else should be screened for tumors?

*Pancreas* Pt has *Multiple Endocrine Neoplasia Type I (MEN I)* due to mutation is TSG menin. Char by: *Parathyroid, Pancreas, and Pituitary tumors (3 P's)* -*Primary Hyperthyroidism*: recurrent renal stones (1st manifestation) -*Pituitary*: tends to present as hyperprolactinemia (female w/o menses or galactorrhea w/ postmenopaus) or HAs or bitemporal visual field/clumsiness -*Pancreas*: gastronoma (Z-E Syndrome) > insulinoma (mortality) #1845

A mutation in trypsinogen is discovered that prevents trypsin from being permanently inactivated by enzymatic cleavage. Pts w/ this mutation would most likely develop what?

*Pancreatitis* *Hereditary Pancreatitis* is a rare disorder w/ mutations in *trypsinogen or SPINK1 gene*, which is responsible for pancreatic acing production of a protein that *prevents premature activation of trypsin in the pancreas* #433

61yo female has a neck lump but otherwise feels normal. Vitals: 98F, BP 115/70, and HR 78. PE: nontender, firm nodule in the L lobe of the thyroid. Normal TSH levels. Thyroid US: 2 cm, hypoechoic thyroid nodule w/ increased central blood flow. Biopsy: clusters of cells w/ large, overlapping nuclei containing sparse, finely dispersed chromatin. Numerous internuclear inclusion bodies and grooves noted. Dx?

*Papillary Carcinoma* *Papillar CA* is the most common thyroid CA. Risk factors: fam hx and radiation exposure. They have characteristic *finely dispersed chromatin*, giving them a ground glass appearance (*Orphan Annie Eye*). *Intranuclear inclusion and grooves* also seen. Psammoma bodies! #1658

Where would testicular cancer metastasize to?

*Para-aortic lymph nodes* -"retroperitoneal LNs" #2021

Pt dx w/ pheochromocytoma. The cells responsible for pt's disease have a common embryologic origin w/ which cell line?

*Parafollicular Cells* *Neural crest cells give rise to*: thyroid parafollicular cells and chromatin cells of adrenal medulla -*MOTEL PASS*: Melanocytes, Odontoblasts, Tracheal cartilage, Enterochromaffin cells, Laryngeal Cartilage, Parafollicular Cells, Adrenal Medulla/All ganglia, Schwann Cells, and Spinal Membrane #771

45 yo female w/ c/o 4mo hx of HAs and blurred vision. PMH--. Abdominal CT shows a 2cm L-sided adrenal mass. Gross exam shows a well-defined yellowish tumor w/in the cortex. If the tumor cells are functionally similar to those of the outermost layer of adrenal cortex, what additional sxs would this pt have?

*Paresthesias and muscle weakness* Pt has *Primary Hyperaldosteronism* due to an *aldosterone-secreting adenoma* (*Conn Syndrome*). *Aldosterone* stimulates renal cortical collecting duct cells to increase *exchange of Na+ for K+ and H+* (Na+ retention w/ K+/H+ excretion)=> HTN, hypoK+, and metabolic alkalosis -Electrolyte abnormalities cause sxs #454

3yo male w/ c/o 1hr oral bleeding post-tooth extraction. PMH: --. Vitals: BP 90/60 and HR 100. PE: slow oozing of blood from site of dental extraction. Fam hx: maternal uncle w/ bleeding into his joints. What lab would be abnormal?

*Partial Thromboplastin Time* Pt's hx and fam hx is suggestive of an *X-linked Coagulopathy*, such as Factor VII or IX deficiency (which are clinically indistinguishable). Both have *isolated prolongation of PTT* due to defects in *intrinsic pathway*. PT and thrombin time are normal in hemophilia pts. Tx: replace factor and desmopressin #1953

Pt c/o leg swelling after dog (who was vaccinated) bit him the night before, leading to skin breakage and bleeding. Pt washed w/ soap and water. This morning he noticed that it was warm, red, and swollen. Afebrile. No wound drainage or creptitus. Distal pulses palpable. Wound cultures show G-- coccobacilli w/ mouse-like odor. What microbe is responsible?

*Pasturella multicida* *Dog bite* more likely have P. multicida, S. aureus, or Streptococcus sp. #11547

Small for gestational age infant born prematurely. PE: small head and eyes as well as cleft lip and palate. There's a small, punched-out lesion w/ an overlying thin membrane on the pt's scalp. A small membranous sac w/ a loop of bowel protrudes from pt's abdominal midline. Dx?

*Patau Syndrome* *Patau Syndrome* (Trisomy 13) has phenotypic features due to a defect in fusion of the *prechordal mesoderm*. Midline defects: *holoprosencephaly*, microcephaly, *microphthalmia, cleft lip/palate, and omphalocele*. Intellectual disability and seizures. May also have *polydactyly and cutis aplasia* #1822

32 yo female c/o progressive exertion dyspnea and easy fatiguability. Immigrated a few yrs ago. PMH: Rheumatic Fever as a child. Cardiac: diastolic high frequency sound and a rumbling diastolic murmur best heard at apex. Where on the Wigger's Diagram would the high-frequency sound be heard?

*Peak pressure in left atrium* Pt has *Mitral Stenosis* due to PMH of Rheumatic Fever. There's an *early diastolic high-frequency opening snap* and a *low-pitched diastolic rumble*. -severity of MS is based on how early the opening snap is #235

67 yo male w/ c/o progressive SOB and chest tightness. No lightheadedness or syncope. Lisinopril for HTN and metformin for T2DM. 40 pack yrs. BP cuff inflated to 140 mmHg and deflated slowly. At 120mmHg, Korotkoff sounds are heard only w/ expiration. At 100mmHg, Korotkoff sounds are heard throughout RR cycle. This PE finding can be seen in what condition?

*Pericardial Disease* Systemic arterial pressure decreases <10mmH during inspiration; however, *Pulsus Paradoxus* has an exaggerated decrease (>10) during inspiration. Detected as above. This difference btwn systolic P. at which *Korotkoff sounds* first appear and are heard throughout defines pulsus paradoxus (20mmHg for this pt). -*increased RV preload* w/ inspiration->*bowing of IVS* toward LV-> decreased LV EDV, LV stroke volume, and SBP #2099

What structure is most likely cut in a vertical, midline episiotomy?

*Perineal Body* *Perineal Body* is essential for integrity of the pelvic floor. It anchors: bulbospongiosus, external anal sphincter, superficial and deep perineal, and levator ani muscles. #11823

Gram-- bacteria is cultured and, as they're actively dividing, they're lysed and DNA extracted. DNA is analyzed, showing presence of uracil. This finding is related to what enzyme?

*Primase* In prokaryotic DNA replication, *Primase (RNA Polymerase)* is responsible for synthesizing a short RNA primer, allowing DNA polymerase to initiate DNA synthesis #2017

4yo male has several episodes of vomiting following the consumption of mysterious mushrooms in the park. PMH--. He's intubated due to somnolence. Analysis of this mushrooms shows they stimulate muscarinic receptors. What is the direct effect of this poison?

*Peripheral Vasodilation* *Muscarinic agonism increases parasympathetic activity* and M2 and M3 are the primary causes of sxs. *M3 Rs.* are found on *endothelial cells* and agonism causes production of *nitric oxide (NO)*, which diffuses down to *vascular smooth muscle cells*-> increased cGMP-> *activation of myosin light chain phosphatase*-> no interaction btwn myosin and actin-> *smooth muscle relaxation and vasodilation* -all other tissues constrict w/ muscarinic agonism! #1361

34 yo female has Multiple Sclerosis. What would best describe her pathologic brain lesion?

*Periventricular Inflammatory Cells* *Multiple Sclerosis* is an immune-related disorder characterized by focal lesions of demyelination. *Active MS plaques* are characterized by *periventricular inflammatory infiltrates* made of T cells and macrophages against myelin #919

3wk old male w/ discharge from umbilicus. Post-natal unremarkable w/ loss of umbilical cord around 14d of life. Vitals normal. PE: small reducible umbilical hernia, minimal clear to straw-colored discharge from umbilicus, and erythema around area. Labs: Hb 12, Hct 36%, Leukocytes 11,000, PMNs 50%, and Lymphocytes 45%. What is the cause of this pt's condition?

*Persistence of allantois remnant* Pt has *Patent Urachus*. The yolk sac forms a protrusion (*allantois*) that extends to the urogenital sinus. The upper part of the sinus gives rise to the bladder. Allantois eventually becomes the *urachus*, a duct btwn the yolk sac and bladder. -this is due to the *complete failure of obliteration of urachus* #652

6mos after a cerebral ischemic infarction, what would most likely be observed in the affected pyramidal tracts?

*Persistent Myelin Debris* *Wallerian Degeneration* occurs when axons are damaged, resulting in breakdown of *myelin sheath distal to site of injury*. In the *CNS*, this process is slow. Oligodendrocytes either inactivate or atrophy. The *slow removal of myelin debris* can last for *years*. *Astrocytes* produce inhibitory factors to prevent axonal growth and they proliferate to form a *glial scar* that acts as a *barrier for axonal regeneration*. -glial cells will undergo hyperplasia! -note: calcification of the scar takes years and is rare -note: CNS nerve repair does not involve Oligodendrocytes -note: PNS nerve repair DOES involve Schwann cells #11576

Bordetella pertussis toxins

*Pertussis toxin*: disinhibits adenylate cyclase through G1 ADP-ribosylation, increasing cAMP levels; causes edema and phagocyte dysfx *Adenylate cyclase toxin*: fxs as an adenylate cyclase, increasing cAMP levels; causes edema and phagocyte dysfx

Vascular tone is measured w/ administration of NE and w/ Drug A and NE. Graph shows decreased maximal effect. Drug A is similar to what agent?

*Phenoxybenzamine* *NE* has a1 agonism and B1 agonism, making it a vasoconstrictor. *Drug A* shows *decreased maximal effect (Vmax)* w/o change to affinity (Km) for a1 Rs. This means the drug is either a *noncompetitive antagonist or irreversible antagonist* of a1 Rs. -*Phenoxybenzamine* is an irreversible a1 antagonist for pheochromocytoma tx -change in Km would be a L or R curve shift #1947

67 yo male admitted to R lower lobe pneumonia develops hypoTN and lactic acidosis. He's started on a NE drip. A few hours later, the antecubital vein being infused blanches and the tissues surrounding IV site become cold, hard, and pale. Local injection of what would provide greatest benefit?

*Phentolamine* Pt is experiencing *norepinephrine extravasation*. The NE leak causes *intense a1 R. mediated vasoconstriction*, which can lead to necrosis. *Phentolamine* is an *a1 R. antagonist* and must be given w/in 12hrs to be effective. #1164

What enzyme converts NE-Epi?

*Phenylethanolamine-N-Methyltransferase (PMNT)* -effects are exacerbated by cortisol -Tyr dx #602

43 yo male w/ multiple dxs, including seizure and mental illness. PE shows a mouth w/ enlarged, pale gums. What drug is responsible for sxs?

*Phenytoin* Pt has *gingival hyperplasia*, a common Se of *Phenytoin* often taken for tonic-clonic, status epilepticus, and partial seizures. It *blocks v-gated Na+ channels in neurons*. Low therapeutic index. -CNS tox: ataxia and nystagmus -long-term tx SEs: gingival hyperplasia, coarse facial features, and hirsutism -alters metabolism of folic acid -induces P450 -contraindicated in pregnancy=> fetal hydantoin syndrome #1197

6 mo old male w/ concerns of not developing normally. Feeding regularly. Had a mild RR infection 1 mo ago. Not as interactive as other kids. PE: delayed developmental milestones and hypotonia. 2 yrs later, kid has involuntary movements and a tendency to bite his own lips and fingers. Labs: increased uric acid. What enzyme is increased?

*Phophoribosyl Pyrophosphate Amidotransferase (PRPP Amidotransferase)* Pt has *Lesch-Nyhan Syndrome*, an *XLR disorder* characterized by dystonia, choreoathetosis, self-mutilation, and *hyperuricemia*. Due to *HGPRT deficiency*, which is important in *purine salvage pathway* to convert *hypoxanthine to IMP* and *guanine to GMP* -*PRPP A* is inhibited by AMP, GMP, and IMP #2067

W/ increasing gestational age, 2 components are measured. One starts out lower and increases drastically a 30wks; whereas, the other starts off higher but kind of levels off. What are these 2 compounds?

*Phosphatidylcholine and Sphingomyelin* *Phosphatidylcholine* (lecithin) is a component of surfactant and *Sphingomyelin* is a component of membrane phospholipid. Lung maturity is measured by *L/S ratio* and 2:1 or higher means they're mature (35 wks). -phosphatidylglycerol is produced at 36wks #800

60 yo female w/ long-term COPD is started on high-flow O2 supplementation. Shortly afterward, she becomes increasingly lethargic and confused. Pt's clinical decline is associated w/ increase in what parameter?

*Physiologic Dead Space* *Supplemental O2* in *COPD* pts may cause *Oxygen-Induced Hypercapnia* b/c high O2 concentration can lead to increased CO2 retention. The major cause is b/c of *increased V/Q mismatch*. This happens b/c supplemental O2 increased O2 levels in areas w/ poor ventilation, *reversing pulmonary vasoconstriction*. The redistribution of blood from well-ventilated areas leads to *increased physiologic dead space* w/ decreased total alveolar ventilation xOther mechanisms: -Peripheral chemoreceptor simulation (normal COPD)-> addition of O2-> *decreased chemoreceptor stimulation*-> *decreased minute ventilation*-> increased CO2 retention -High Hb affinity for CO2 (normal COPD)-> *decreased Hb affinity for CO2 (Haldane)*-> increased blood PCO2-> Increased CO2 #12141

78yo pt admitted for bronchoscopy receives IM Atropine and becomes acutely restless, disoriented, and combative. Vitals: 100.5F, BP 116/72, HR 110, and RR 15. PE: pupils dilated and not reactive to light. What tx reverses signs and sxs?

*Physostigmine* *Atropine* is an *anticholinergic* that inhibits muscarinic receptors both centrally and peripherally. The elderly are especially susceptible. *Cholinesterase inhibitors* will increase ACh at synaptic cleft. *Tertiary Amines (Physostigmine)* can cross BBB and will fix all signs and sxs -Quaternary Amines (Neostigmine and Edrophium) cannot cross BBB and only fix peripheral sxs #1564

14 yo male presents w/ n/v, generalized HA, ataxia, and visual complaints. HAs wake him up nightly for 6wks. MRI: cystic tumor in cerebellum. Biopsy: well-differentiated neoplasm comprised of spindle cells that have hair-like glial processes and are associated w/ micro cysts. Cells are mixed w/ Rosenthal fibers and granular eosinophilic bodies. Dx?

*Pilocystic Astrocytoma* #1153

12yo male c/o gait instability and HAs for several mos. Brain MRI: a large mass in cerebellum of 2 densities. Dx?

*Pilocytic Astrocytoma* *Pilocytic Astrocytomas* are the most common brain tumors in *children* and present w/ *cystic and solid components* w/in the *cerebellum*. They're *low-grade* gliomas. Histo: pilocytic astrocytes w/ bundles of *GFAP + hair-like processes* and classic *Rosenthal Fibers* (eosinophilic intracytoplasmic inclusions). #615

65 yo male c/o fever, chills, and confusion. Hx of poorly-controlled DM w/ a non healing ulcer of the L foot. Vitals: 101F, BP 90/60, HR 112, and RR 22. PE: slight erythema around L foot ulcer and foul-smelling discharge. Blood cultures show B-lactamase-producing Bacteroides sp. What antibiotic should be used?

*Piperacillin-Tazobactam* *G-- anaerobic rods* are susceptible to: Piperacillin-Tazobactam, Metronidazole, Carbepenems, and Clindamycin -can also add Clavulanate to inhibit B-lactamase #1198

30 yo male c/o 4d hx of progressively worsening abdominal pain and bloody diarrhea. He was started on Mesalamine 6mos ago for Ulcerative Colitis but has been noncompliant. Vitals: 102F, BP 100/70, and HR 130. Pt is lethargic w/ dry mucous membranes. There's abdominal distention and tenderness w/o rebound or guarding. Rectal exam: guanaco +, maroon-colored liquid stool. What is next step in pt workup?

*Plain Abdominal X-ray* Pt w/ abdominal pain/distension, dysentery, fever, and signs of shock in the setting of untreated Ulcerative Colitis has a *Toxic Megacolon*. UC>Crohn's. It's highly associated w/ *Clostridium difficile*. Pathophysiology begins w/ colonic smooth muscle paralysis-> rapid distention-> perforation. *Plain abdominal x-ray* is diagnostic b/c it'll show *colonic dilation* w/ multiple air fluid levels. -barium enema and colonoscopy are contraindicated b/c it may cause a perforation #410

34 yo male c/o difficult walking. He fell and punctured his R leg. PE: R foot is dorsiflexed and everted. Pt is unable to stand on his tiptoes. Muscle strength at hip and knee are intact. Xray-- for fracture. Where does he have sensory loss?

*Plantar Foot* Pt damaged his *Tibial N. (L4-S3)*. This is the medial branch of the sciatic nerve that travels through the *popliteal fossa* and enters the *deep posterior compartment*. It enter plantar aspect of foot via tarsal tunnel (btwn flexor retinaculum and medial aspect of talus and calcaneus). *Complete motor loss*: cannot plantar flex, invert foot, or flex toes 2-5. *Complete Sensory Loss*: sole of foot #1638

A comparison of pts w/ hormone receptor + breast cancer who had disease recurrence and who remained cancer free showed that some of the relapsed pts had lower serum concentration of edoxifen and 4-hydroxytamoxifen, the active metabolites of Tamoxifen. What is the likely cause of drug's ineffectiveness?

*Polymorphism of a cytochrome P-450 enzyme* *CYP polymorphisms* are expressed as: *poor, intermediate, or fast metabolizers*. *Tamoxifen* is metabolized by CYP2D to *active endoxifen*. Poor metabolizers will have decreased effect b/c of decreased conversion to active metabolite. #1711

54yo male suffers TBI in an MVA. He was found unresponsive and had several generalized tonic-clonic seizures. PMH: HTN and alcohol and cocaine abuse. Vitals: 98F, BP 170/96, HR 50, and RR 10. Pulse O2 is 98% on mechanical ventilation w/ 50% O2. PE: pt is comatose w/ mid-positioned and fixed pupils and rigid extension of UEs and LEs. Damage to what neural structure caused this pt's abnormal posturing?

*Pons* Pt has a *transtentorial (uncal) herniation*. Hematoma expansion increases ICP and induces *brainstem (Pons) compression* w/ Cushing's Triad (HTN, bradycardia, and RR depression). *Damage to brainstem at or below red nucleus (midbrain tegmentum/Pons)* usually causes *extensor posturing* due to loss of descending excitation to upper limb flexors #11574

What is abnormal in LN anatomy in DiGeorge kids?

*Poor development of Paracortex Region* -Deficiency in mature T cells -Paracortex would only have dendritic cells #8532

28 yo female c/o acute-onset abdominal pain, nausea, and confusion. PMH--. No alcohol or tobacco b/c they "make her feel sick." Serum lipase and LFTs are normal. Abdominal CT normal. Urine is reddish in color and darkens on 24hr standing. IV dextrose is administered and sxs improve. Dextrose infusion affected which pathway?

*Porphyrin Synthesis* Pt has *Acute Intermittent Porphyria*, and *AD Disorder* of heme synthesis due to the lack of *Porphobilinogen Deaminase* (cytosolic enzyme). It presents *acutely* w/ variable *GI and neurologic sxs* most commonly abdominal pain, vomiting, peripheral neuropathy, and neuropsych sxs. Reddish urine that darkens is b/c of increased PBG. Tx and prevention is accomplished by *inhibiting ALA Synthase* to decrease toxic metabolites. ALA Synthase is *upregulated* by *CYP inducers* and *downregulated* by *heme and glucose*. Avoid tobacco and alcohol b/c they induce cyps! #1339

46yo male c/o sudden-onset large volume hematemesis. He was working and experience nausea and started vomiting bright red blood. PE: palpable spleen. Endoscopy: esophageal varices. Liver biopsy 2ds later: normal. Cause of pt's condition?

*Portal Vein Thrombosis* *Portal HTN* induces esophageal and splenic varices. This is a pre sinusoidal process, thus there is no pathology w/ the liver #1701

55 yo male c/o persistent R arm tingling and numbness for several hrs. No other stroke-like sxs. PMH: HTN, paroxysmal A-fib, and ischemic stroke w/o residual sxs. His anticoagulant was discontinues 2mos ago b/c of GI bleeding. Vitals: BP 150/90. While in ER, he experiences R-sided paresthesias, progresses to R-sided convulsions, and followed by generalized tonic-clonic seizure. Where in the L. cerebral hemisphere did the seizure originate?

*Postcentral Gyrus* Seizure started out *sensory* and then progressed to motor... #12008

28yo G2P2 c/o worsening SOB for 1wk and an episode of hemoptysis. Pt has had ongoing vaginal bleeding after an uncomplicated delivery of her son 9wks ago. No other bleeding and has yet to have sex again. PE: enlarged uterus w/ normal adnexa. Labs: markedly increased B-hCG. CXR: bilateral lung nodules. What would be seen on endometrial curettage?

*Proliferation of cytotrophoblasts and synctiotrophoblasts* *Gestational Choriocarcinoma* is a *malignant* tumor arising from *trophoblasts*. It most commonly follows a normal pregnancy. Tumor causes *abnormal vaginal bleeding*, uterine enlargement, and *increased B-hCG*. ChorioCA tends to have *hematogenous spread* to the *lungs* (SOB and hemoptysis). Histo: diffusely anaplastic/necrotic w/ vascular invasion. *Villi absent* #335

55 yo female c/o n, fatigue, fever, and anorexia. Just returned from Mexico, where she had an emergency cholecystectomy w/o complications. Vitals: 101F, BP 100/60, HR 90, and RR 12. Pt is alert and oriented but appears extremely weak and slightly icteric. PMH --. Meds --. Condition worsened over next 2d. Viral serology --. Dies. Gross exam of liver is small. What additional findings would be found?

*Prolonged Prothrombin Time* Pt has *Drug-Induced Liver Injury* most likely associated w/ inhaled anesthetic. *Inhaled-Anesthetic Hepatotoxicity* is frequently associated w/ *halothan*, causing *hepatocellular pattern* of acute liver injury. Sxs range from asymptomatic to fulminant hepatitis. -thought to be a hypersensitivity rxn -Labs: increased ALT and AST; decreased VII and K+ coagulation factors #369

23yo male c/o sudden-onset heart palpitations that started at rest. PMH: --. Initial vitals: BP 110/70 and HR 160. Neck massage provides immediate improvement. New vitals: BP 120/80 and HR 75. What mechanism is responsible for change in condition?

*Prolonged atrioventricular node refractory period* Sudden-onset palpitations and rapid and regular tachycardia is indicative of *Paroxysmal Supraventricular Tachycardia (PSVT)*, which is often b/c of *reentrant impulse* traveling btwn the *conducting segments of AV node. Vagal maneuvers* (carotid massage, Valsalva, and cold water) can acutely terminate PSVT. *Carotid Sinus* (afferent = IX; efferent = X) sends parasympathetics to *SA and AV nodes*. Massage *increases baroreceptor firing* to then *increase vagal parasympathetic tone*, thus *slowing conduction through AV node and prolonging AV node refractory period*. -will see decreased systemic vascular resistance #1515

53 yo male w/ DM gets in MVA and breaks leg. In hospital, he receives NPH insulin and regular insulin. Blood glucose decreases below 50 mg/dL several times, but only sxs in hypoglycemic episodes are sweating and hunger. What medication is responsible?

*Propranolol* *Non-selective B-Blockers* (Propranolol, Timolol, and Nadolol) *inhibit NE/Epi-mediated compensatory reactions to hypoglycemia* (masks adrenergic sxs) -B2 blockade inhibits hepatic gluconeogenesis and peripheral glycogenolysis and lipolysis -increased risk of hypoglycemia and decreased pt awareness of hypoglycemia -use a *B1 blocker instead!* (Pindolol or Acebutol) #1492

A study of 400 females (40% smokers and 60% non-smokers) for 10 yrs shows 25 smokers and 24 non-smokers developed breast cancer. What type of study design is this?

*Prospective Cohort Study* This is when a cohort is selected, their exposure status is determined, and followed for a period of time to observe the outcome #1203

57 yo male w/ Dyslipidemia is found to have persistently, drastically increased levels of TGs, despite vibrates. The doc administered a drug that causes facial flushing and warmth. What primary agent mediates these SEs?

*Prostaglandin* Pt is started on *Niacin* to increase HDL and super decrease TGs. *Flushing and itching* are mediated by PGs (*PGD2 and PGE2*). -co-administer w/ *Aspirin* or take niacin w/ meals to decrease these SEs #160

70 yo male has prostatic mets to his lumbar vertebral area. What structure helped them get there?

*Prostatic Venous Plexus* *Vertebral venous plexus* allows for hematogenous spread from *prostatic venous plexus*, which runs up and down the spinal column. Its valveless w/ didirectional flow and allows for regulation of ICP. #11747

72 yo female on warfarin experiences severe skin and subcutaneous fat necrosis. Drug effect on what process is responsible for skin findings?

*Protein C Activity* Pt has *Warfarin-induced skin necrosis* thought to be due to a *transient hyper coagulable state*. Warfarin also decreased synthesis of Proteins C and S. *Protein C* has a *short T1/2*, so its anticoagulant activity is decreased very rapidly. #1088

Glucagon binds transmembrane receptors in hepatocytes, which promotes binding of intracellular GTP to a specific receptor-associated protein. This causes further downstream signaling and changes. What is the most likely mediator of these effects?

*Protein Kinase A* *Glucagon*->GPCR-> alpha subunit *Gs* undergoes conformational change -> exchanges GDP for GTP -> alpha subunit dissociates and *activates Adenylate Cyclase* -> *increased cAMP* -> *activation of Protein Kinase A* -> phosphorylation of Ser/Thr residues w/ transcriptional modification activity #994

GAS has significant resistance to phagocytic killing. Resistance can be overcome by Abs to what?

*Protein M* *Protein M* is *GAS'* major VF and *inhibits phagocytosis and C' activation*. -its also cytotoxic against PMNs #723

58 yo male w/ hematuria has kidney biopsy that shows rounded and polygonal cells w/ abundant cytoplasm. This lesion originates from what portion of the kidney?

*Proximal Renal Tubules* Pt has *Renal Cell Carcinoma*, the most common renal neoplasia and microscopically *clear cell carcinoma*. These originate from *proximal renal tubules* an are associated w/ smoking and obesity #905

24 yo female comes to ED b/c of fever and chills for 24 hrs. 3wks ago, she had a partial bowel resection due to Crohn's disease and had feeding difficulties ever since. They inserted a central venous catheter to receive TPN. Vitals: 101F, BP 100/60, and HR 114. Surgical wound healed well. Catheter site is tender w/o erythema. CXR: shows correctly place catheter. Blood cultures are + for yeast. What is the microscopic characteristic of this yeast?

*Pseudohyphae with blastoconidia* *Catheter-induced Fungemia* is associated w/ *Candida sp.* #11633

39 yo paraplegic male w/ an indwelling catheter develops acute pyelonephritis. Urinalysis: 3+ leukocyte esterase and WBC casts. Urine culture: non-lactose fermenting G-- rods. What pathogen is the most likely culprit?

*Pseudomonas aeruginosa* #1146

32 yo male hospitalized w/ n/v and severe abdominal pain. Hx of alcohol abuse and had acute pancreatitis 1 yr ago. Continued drinking and had a fifth of alcohol last night. Vitals: 101F, BP 110/80, HR 104, and RR 20. Abdomen has marked tenderness in epigastric region. CXR: new bilateral opacities. 24hr fluid intake 2,800mL and output 1,800mL. What parameter is normal?

*Pulmonary Capillary Wedge Pressure* Pt has *ARDS*, which acute pancreatitis is a risk factor for. This is characterized by *diffuse injury to pulmonary microvascular endothelium and alveolar epithelium*, increasing capillary permeability. This results in noncardiogenic pulmonary edema w/ *normal (6-12mmHg) pulmonary capillary wedge pressure*. -lung compliance decreases (hyalinosis) -atelectasis can cause V/Q mismatch by decreasing ventilation #486

A pt w/ obstructive sleep apnea is at increased risk of developing what?

*Pulmonary Hypertension* *Obstructive Sleep Apnea* vignettes are usually an overweight male w/ loud snoring, daytime sleepiness, and a thick neck/narrow airway. Recurrent nocturnal airway obstruction causes transient *hypercapnia and hypoxemia*. These blood gas changes induce reflexive systemic and *pulmonary vasoconstriction*, endothelial dysfx, abnormal venous return, cardiac output, and *sympathetic cardiac stimulation*. Prolonged, untreated OSA can cause *Pulmonary HTN* and R-sided HF. May develop *systemic HTN* due to chronic sympathetic activation and increased NE levels -other random complications: A-fib, CAD, and increased risk of sudden cardiac death #1985

12yo WM is found to have a wide, fixed splitting S2. He denies sxs. This congenital heart disease may require repair to prevent irreversible changes in the:

*Pulmonary Vessels* The fixed splitting is consistent w/ *Atrial Septal Defect*, which creates a L->R shunt. After long-term ASD, an *Eisenmenger Syndrome* occurs and it is now a R->L shunt. Because of this shift in shunts, pathology will be found in all pulmonary vessels -chronic pulmonary HTN will occur #201

Slow rising pulse w/ low amplitude

*Pulsus parvus de tardus* due to decreased stroke volume and prolonged LV ejection time -due to fixed LV obstructive outflow (valvular aortic stenosis)

48 yo male c/o "bump" in his groin. PE: R. inguinal LAD and R. popliteal LAD. This distribution of LAD is seen in which condition?

*Purulent laceration on the R. lateral foot* In the *lower extremities*, the superficial LV drainage is separated in medial and lateral tracts. *Lateral lesions* communicate w/ *popliteal and inguinal LNs* -*Medial lesions* bypass the popliteal Los and go straight to *inguinal LNs* #11830

Hepatocytes are grown in glutamate-rich media w/ nitrogen isotopes. After some time, the Nitrogen isotopes are transferred to Oxaloacetate, forming Aspartate. What cofactor is involved?

*Pyridoxine* *Pyridoxine (B6)* is important for *transamination and decarboxylation* of aas for gluconeogenesis. *Transamination* occurs btwn an *aa* and an *a-ketoacid* to form a new aa -this is the connection btwn TCA cycle and urea cycle #1482

5yo male w/ developmental delay has difficulty seeing the board in class. PE: tall, thin habitus w/ elongated extremities. Fundoscopy: bilateral lens subluxation. 4yrs later, he dies of CVA. Autopsy: middle cerebral artery thrombosis and old infarcts. What supplement could have prevented this?

*Pyridoxine* Pt has *Homocystinuria*, and *AR disorder* most often due to a deficiency in *cystathione B-synthase*, which requires the cofactor *Pyridoxine (B6)*. This methionine metabolism error presents w/ *ectopia lentis (dislocated lens)*, 1/2 have *intellectual disability, Marafanoid Habitus, and thromboembolic occlusions*. #1504

Streptococcus pyogenes toxins

*Pyrogenic exotoxin*: acts as a super antigen, inducing ever and shock; associated w/ scarlet fever and streptococcal toxic shock syndrome *Streptolysin O & S*: damages erythrocyte membranes, causing B-hemolysis

64yo male c/o severe abdominal pain and n/v. PMH: HTN, MI, and systolic HF. Vitals: BP 100/60, HR 116, and RR 24. PE: soft, mildly distended, and tender abdomen. Serum Labs: Na+ 136, Cl- 96, HCO3- 12 (low), and lactic acid 6.2 (increased). Arterial gasses: pH 7.2 (low) and PaCO2 26 (low). Abdominal CT: distal ileal wall thickening and lack of enhancement w/ contrast. Decreased activity of what enzyme explains this pt's acid-base disorder?

*Pyruvate Dehydrogenase* Pt has *Acute Mesenteric Ischemia*. Due to the lack of O2 there's an *increase in intracellular NADPH*, causing *PDH to be inhibited* and pyruvate must now undergo anaerobic metabolism via *Lactate Dehydrogenase* to produce lactic acid #996

31 yo previously healthy male c/o myalgia, anorexia, and skin rash. He's a personal trainer. Denies anabolic steroids but has consumed a large amount of raw egg whites for several months. PE: macular dermatitis of extremities. Water soluble vitamin is deficient. What biochemical conversion uses this cofactor?

*Pyruvate->Oxaloacetate* Pt has a *Biotin (B7) deficiency*, which is important for *carboxylase enzymes*. It's a *CO2 carrier*. Important for hepatic gluconeogenesis. -*egg whites* have high levels of *biotin-binding avidin* -pts may also experience *metabolic acidosis* #1063

Smoker w/ hx of SOB and mild cough that progresses and has suddenly become worse. Hx: HTN on HCTZ. Normal vitals except Pulse O2 is 86% on room air. Decreased breath sounds on R. CXR shows white out on R. side w/ R-sided tracheal deviation. Dx?

*R. Mainstem Bronchus Obstruction*. *Collapsed lung b/c of bronchial obstruction* caused decreased breath sounds, hemithorax opacification, and deviation of trachea *toward opacification*. -complete collapse is b/c of mainstream bronchus -loss of lung vol./collapse/atelactasis is why trachea deviates towards ipsilateral side. #2116

Cancer biopsy shows malignant cells w/ large nuclei that contain prominent, round, basophilic bodies. What enzyme only fxs w/in this basophilic region of the nucleus?

*RNA Poly. I* This is describing the *nucleolus* and malignant cells have very prominent nucleoli. *RNA Poly I* fxs to *produce 45S pre-rRNA* and is *only found in the nucleolus* #2039

What PFT is increased in a pt w/ Emphysema?

*RV/TLC ratio* -although TLC increases w/ Emphysema, it is increased mainly b/c of increased RV (as seen by air trapping) -FEV1, FVC, and FEV1/FVC are all decreased #1521

6yo female landed on an out-stretched arm. PE: swelling of R elbow and tenderness to palpation over distal humerus. X-ray: suprachondylar humeral fracture w/ anterolateral displacement of the proximal fracture fragment. What structure is at greatest risk of injury?

*Radial Nerve* -common w/ hyperextension injuries #11855

54yo male c/o progressive SOB for 6mos and persistent nonproductive cough. Tobacco --. Vitals: 98F, BP 132/78, HR 74, and RR 16. PE: fine crackles bilaterally and drumstick shaped fingers. CXR: diffuse reticular opacities. PFTs: decreased FVC, increased FEV1/FVC, and expiratory flow rtes that are higher than normal. This pt's supernormal expiratory flow rates are explained by increase in what parameter?

*Radial traction on airway walls* Pt's clinical presentation is suggestive of *interstitial lung disease* that may progress to *pulmonary fibrosis*. There will be *increased lung elastic recoil*, as well as *airway widening* due to increased outward pull *(radial traction)* by surrounding fibrotic tissue. This leads to supranormal expiratory flow rates -RLD pts have decreased lung compliance #1543

46 yo female is a marathon runner that's been unable to train b/c of a vertebral stress fracture. LMP 1yr ago. mother died of breast cancer at 52yo. Xray shows decreased bone density in lumbar vertebrae. What drug would decrease risk of fracture and breast cancer?

*Raloxifene* *Selective Estrogen Receptor Modulators* (Raloxifene and Tamoxifen) bind estrogen Rs. and exhibit *antagonist and agonist properties in a tissue-specific manner*. *Raloxifene* has *estrogen agonist* activity in *bone* (decreases resorption) and *estrogen antagonist* activity in *breast* (decreases risk of breast cancer). Also exhibits *estrogen antagonist* activity in *uterus* (not increasing risk of endometrial CA) -*Tamoxifen* has the same R. distribution, except it causes *endometrial estrogen agonism* (increasing risk of endometrial CA) so it is not used for osteoporosis #1795

29 yo female dx w/ anxiety disorder started on Fluoxetine. It works by inhibiting reuptake of a NT released by neurons found where?

*Raphe Nuclei* *Serotonin-secreting neurons* are found in the *Raphe Nuclei* of the brainstem. *Fluoxetine is an SSRI* #1834

45 yo male w/ c/o fever, severe HA, myalgia, and pleuritic chest pain for several days. PE: fever and mild tachycardia. Lungs bilateral crackles. CXR: segmental pulmonary infiltrates. Failes to respond to empiric antibiotic tx. Micro of lung tissue: spherules packed in endospores. Pt hx reveals what?

*Recent travel to Arizona* Pt has *Coccidoides immitus*, which is endemic to SW US, Central America, and South America. Dimorphic fungus: -*25-30C*: mold form w/ hyphae -*37-40C*: spherules containing endospores (human body) #269

Anaphylaxis is mediated by Ag-specific IgE Abs attached to high affinity Rs. on mast cells and basophils. What mechanism is most likely to trigger vasoactive substance release?

*Receptor Aggregation* #2069

72 yo male w/ hx of arterial insufficiency undergoes emergency cholecystectomy. Surgery is complicated by a severe episode of hypoTN. Colonoscopy would show pathology in what portion of large bowel?

*Rectosigmoid Junction* Pt has *Acute Nonocclusive Ischemia Colitis*, which preferentially affects areas of anastomosis. These "*watershed*" areas are primarily in the L colon at the *splenic flexure* (border of SMA and IMA) and *rectosigmoid junction* (border of sigmoid A. and superior rectal A.) #413

10 yo male is an immigrant and has required several blood transfusions for anemia. Afebrile. BMI 21. PE: conjunctival pallor and splenomegaly. Labs: Hb 9.4 and platelets 240,000. Fount to have pyruvate kinase deficiency. What caused the splenomegaly?

*Red Pulp Hyperplasia* *Pyruvate Kinase* normally converts Phosphoenolpyruvate->Pyruvate to generate *ATP*. Mature RBCs lack mitochondria and rely on lactate to maintain glycolysis. Most ATP produced is used for cation transport across RBC membrane. Thus, defective ATP production disrupts gradient, causing water and K+ loss, defective membrane architecture, and *hemolysis. Splenic red pulp* removes damaged RBCs and will undergo *hyperplasia* to accommodate increased destruction. #1020

26 yo female w/ acute-onset diplopia. Had hx of blurry vision in R eye two separate times, 6mos and 2 yrs ago. Events were assoc. w/ deficits in color vision and pain. Most of the sxs have regressed. PE: 20/20 OS and 20/40 OD, R optic disk atrophy, and R afferent pupillary defect. Slowed and impaired adduction of L eye w/ R lateral gaze. Pt's diplopia is caused by what mechanism?

*Reduced saltatory conduction* Pt has *Internuclear Ophthalmoplegia* (impair adduction on L eye w/ R lateral gaze). Previous *optic neuritis* (blurred vision and pain w/ eye movement) raises concerns for *multiple sclerosis*. -AI disorder against *oligodendrocytes*, decreasing saltatory conduction #917

36 yo sedentary male w/ Labs: cholesterol 290, HDL 45, LDL 110, and TGs 675. Is stable on a Fibrate. this helps the pt via what mechanism?

*Reducing hepatic VLDL production* *LPL* hydrolyzes TGs from VLDL and CMs to release FFAs, which are then transferred to HDL via LPL. *Fibrates* (Gemfibrozil and Fenofibrate) activate *PPAR-a*, which leads to *decreased hepatic VLDL production* and *increased LPL activity.* This decreases TGs by 25-50% and increases HDL by 5-20%. -*Fish oil's omega-3-FAs* also *decreases VLDL production* and *inhibits synthesis of apoB* #11844

70 yo male tx w/ Metoprolol for long-standing HTN. PMH: coronary A. disease. Long smoking hx and cannot quit. Enalapril is added. BP normalizes but labs show increased serum Cr levels. What is the best explanation for what happened?

*Reduction in renal filtration fraction* *ACEi* can precipitate *acute renal failure* in susceptible pts. This is b/c *Angiotensin II* is a powerful *vasoconstrictor* that *maintains GFR* in pts w/ renovascular HTN (this pt!) by causing *efferent arteriolar constriction* and increasing GFR and RBF and FF. ACEi in this pt decreases Angiotensin II, causing efferent arteriolar dilation, decreasing GFR, RBF, and FF. Pts w/ a hx of coronary A. disease should caution ACEi usage. #694

What is the most common valvular disease predisposing to the development of Infective Endocarditis in developed countries?

*Reguritant Mitral Valve Prolapse* -rheumatic heart disease is for developing countries #230

24 yo G1P0 comes to L&D at 28wks gestation w/ c/o intense abdominal pain, vaginal bleeding, and decreased fetal movement. Vitals: 98F and BP 170/96. US: hematoma btwn the placenta and uterine wall w/o fetal heartbeat. Labs: Hb 9.2 (low), Platelet 60,000 (low), AST 12, and ALT 24. She begins to bleed from her orifices. What is the cause of bleeding?

*Release of tissue factor into the the maternal circulation* *DIC* risk factors permpartum: *placental abruption* (this case), sepsis, postpartum hemorrhage, HELLP, and amniotic fluid embolism. In pregnancy, DIC is mediated by *tissue factor* (thromboplastin) released by trophoblasts at sites of *placental injury*, initiating the *coagulation cascade* #1296

18 yo male c/o progressive skin rash for 1yr. Also has a long-standing hx of intermittent burning sensation of palms and soles that's exacerbated by stress and fatigue. Pt notes that he sweats minimally. PE: clusters of non-blanching, red papule in the gluteal, inguinal, and umbilical areas. Labs: undetectable a-galactosidase A. What condition is this pt at greatest risk for developing?

*Renal Failure* Pt has *Fabry Disease*, an *XLR lipid storage disorder* due to the lack of *a-galactosidase A*, which I a lysosomal enzyme responsible for *breaking down globotriaosylceramide* (Gb3). Gb3 accumulates in vascular smooth muscle, glomerular/renal tubules, cardiomyocytes, and Autonomic and DRG. Early sxs are *neuropathic pain and hypohidrosis*, which are exacerbated by fatigue, stress, and exercise. Late adolescence sxs present as *angiokeratomas and telangiectasis*. Adulthood, the most common CoD: *cerebrovascular disease* (ischemia/stroke) or *cardiac disease* (LV hypertrophy). Gb3 building up kidneys may also lead to *porteinuria and polyuria*, that may progress to *renal failure*. #1989

1 hr old male is tachycardia and hypoxic. Born to term via C-section. No prenatal care. Low birth wt. PE shows flattened nose and bilateral clubbed feet. Breath sounds diminished bilaterally. O2 levels do not improve despite intubation. Dies 1hr later. What is found on autopsy?

*Renal agenesis* Pt has *Potter Sequence* (pulmonary hypoplasia, flat facies, and limb deformities), This is due to a *renal anomaly* that *decreases urine output of fetus*. -oligohydraminos present #1752

How would a graph assessing airway resistance as it passes through trachea, medium sized bronchi, and ultimately terminal bronchioles look?

*Resistance starts out about 70% resistant at trachea, rises as it gets to medium-sided bronchi, and bottoms out at terminal bronchioles* -it increases at md-sized bronchi b/c of increased turbulence -it decreases after that b/c of increased cross-sectional area #481

24 yo AAF c/o fever, malaise, and intense pain in R thigh. She has a long hx of sick cell crises. This episode of pain is very different as she is febrile (103F) w/ equisite tenderness over R thigh. No skin changes. MRI taken and antibiotics administered. Cultures: non-lactose fermenting, oxidase --, motile organisms. What virulence mechanism aided in this presentation?

*Resistance to opsonization* *Sickle cell pts* are at increased risk of *Salmonella osteomyelitis*. Salmonella sp. has a special *capsule called the "Vi Ag"* that protects it from *opsonization* and phagocytosis. #1137

23 yo male in DKA. Vitals: 100F, BP 96/58, and HR 112. PE: dry mucous membranes and urine has a strong fruity odor. Labs: Na+ 134 (low), K+ 3.8 (low/norm), Cl- 100 (norm), HCO3- 14 (very low), Cr 1.0 (norm), Glucose 498 (very high), pH 7.17 (very low), and PaCO2 40 (norm). Based on labs, what's happening in pt?

*Respiratory Failure* Pt in *DKA* has an *anion gap metabolic acidosis*. These extra anions (acetoacetate and B-hydroxybutyrate) bind and lower serum HCO3-. Metabolic acidosis develops *compensatory respiratory alkalosis* by hyperventilating (Kussmaul RRs), which induces RR alkalosis and decreases PaCO2. However, this pt's PaCO2 persisted above expected compensation (calculated by Winter's Formula), indicating *superimposed respiratory acidosis*. Pt has a *mixed acid-base disorder* #1979

Pregnant female comes in for US. Fetus is noted to have bilateral enlarged fetal kidneys w/ diffuse small cysts. Oligohydraminos present. No other anomalies. What will be present after delivery?

*Respiratory distress* Pt has *ARPKD* that's assoc. w/ *PKDH1* that encodes for *fibrocystin*. This is found in kidney and liver. Clinical signs: renal insufficiency, nephromegaly, and HTN. Oligohydraminos causes *Potter Sequence*: flattened facies, limb deformities, and pulmonary hypoplasia. #1915

32 yo male w/ c/o progressive fatigue, easy bruising, and recurrent gum bleeding. PE shows several ecchymoses. Labs: decreased Hb, platelet, and WBCs; increased PTT, PT, and D-dimer w/ decreased fibrinogen. BM and FISH are done and show balanced translocation btwn long arms of chromosomes 15 and 17. What protein in hemopoietic stem cells is abnormal?

*Retinoid Acid Receptor* Pt has *Acute Promyelocytic Leukemia* associated w/ *t(15;17)* (PML/RARA) -*Auer Rods*=> DIC/Thrombocytopenia -tx: all-trans retinoid acid (Vitamin A) #1403

71yo male w/ MI goes in for a femoral cardiac Cath. During cannulation of R common femoral artery, the artery wall is penetrated superior to R inguinal ligament. Firm pressure achieves hemostasis. Soon after procedure, pt becomes cold, clammy, and hypotensive. PE: 5 cm region of ecchymosis surrounding the femoral puncture site. Where is his internal bleeding?

*Retroperitoneal Space* *Arterial puncture above the inguinal ligament* increases risk of *retroperitoneal hemorrhage* of the external iliac artery. You know this is retroperitoneal b/c bleeding in the retroperitoneal space *cannot be controlled w/ external pressure* and leads to *hemodynamic instability* (hypoTN, decreased Hb, and flank pain) #11764

54 yo male w/ episodic burning substernal chest pain, that worsens w/ activity and decreases w/ rest is being worked up for ischemic heart disease. A myocardial perfusion study reveals inducible ischemia on inferior surface of the heart. Which coronary A. is occluded?

*Right Coronary Artery* *R. Coronary A.* gives off *Posterior Descending A.* (*R. Dominant Heart*) to supply *posterior 1/3 IVS* and *inferior wall of LV* #1871

Pt has sinus bradycardia and STEMI in leads II, III, and aVF. What coronary A is occluded?

*Right Coronary Artery* -you see sinus bradycardia b/c of decreased blood flow to SA node #179

A cardiac Cath measures pressure changes in one area as max 25 mmHg and minimum 2 mmHg. Its then advanced and measures pressure changes as max 25 mmHg and min 10 mmHg. Where is the first set of readings from?

*Right Ventricle* *SVC/RA*: 1-6 mmHg *RV*: 15-30/2 mmHg *Pulmonary Artery*: 25/10 mmHg *PCWP/LA/LV EDP*: 6-12 mmHg *LV*: 130/10 mmHg *Aorta*: 130/90 mmHg #1653

Pt has Scurvy due to vitamin C deficiency. This deficiency causes hypoactivity of an enzyme found in what compartment?

*Rough Endoplasmic Reticulum* *Proline and Lysine hydroxylation* during normal collagen synthesis occurs in *RER* #1247

78 yo female c/o altered mental status of recent onset and difficulty walking. PMH: Parkinsonism. She's had a few falls recently. Vitals: BP 180/100 and HR 68. Head CT: crescent-shaped mass w/ midline shift. What ruptured?

*Rupture of cortical bridging veins* Pt has a *Subdural Hematoma* due to *rupture of cortical bridging veins* that carry bloody from cortex to sinuses. This is seen in infants and elderly. Venous bleeding means there will be a *gradual onset of sxs* #506

43 yo female presents w/ acute back pain after dragging box. Located in lower back and radiated down posterior thigh to foot. "Shooting" and 8/10. No bowel or bladder sxs. PE: + straight leg raise on R and R hip extension is weaker than L. Knee reflexes 2+ bilaterally, but R ankle jerk is absent. What nerve root is affected?

*S1* Pt has *Sciatica* (back pain that radiated down leg). -most commonly b/c of disc herniation -Sciatic N. = L4-S3 -L5 and S1 are most commonly damaged -*S1 radiculopathy*:see above sxs #1692

46 yo missionary returned from Latin America w/ fever, abdominal pain, and 1 wk hx of watery diarrhea, that recently became bloody. PE: HSM and several faint, erythematous maculopapular lesions on chest and abdomen. Cultures pending. Most likely cause?

*Salmonella typhi* Pt has *Typhoin Fever* from *fecal-oral contamination of food or water* -S. typhi infects M cells -proliferates in macrophages of *Peyer's Patches* -intestinal perforation! -chronic carriers, especially those w/ cholelithiasis #1138

35yo female c/o 3mo hx of progressive dyspnea on exertion, nonproductive cough, and fatigue. PMH: seasonal allergies and she takes antihistamines. She cut down smoking from 1ppd to 4 cigs/d. Fam hx: mom has rheumatoid arthritis. Lung biopsy: non-caveating granulomas. Dx?

*Sarcoidosis* *Sarcoidosis* presents w/ non-caveating granulomas. Typically: *young adults, AA, and female*. CXR: *bilateral hilariously LAD* #795

15 yo male c/o R arm numbness. He's a pitcher on his high school's baseball team and pain is worsened by pitching. He's c/o several weeks of fluctuating tingling and numbness involving R shoulder, arm, and hand and recently developed dull pain in R little finger and hand. PE: decreased sensation over medial 2 fingers and hypothenar eminence of R hand. PMH -- except his was told he has an extra rib. What structure is contributing to his condition?

*Scalene muscles* Pt has *Thoracic Outlet Syndrome*. The pt has an extra *cervical rib* that extends into the *scalene triangle* allowing for *compression* of the lower trunk of the *brachial plexus*, presenting w/ UE numbness, tingling, and weakness. Compression of *Subclavian V.* is associated w/ arm swelling and compression of *Subclavian A.* is associated w/ exertional arm pain. #11778

Liver biopsy of a pt w/ Sarcoidosis would show what?

*Scattered Granulomas* -random fact: sarcoidosis pts have increased ACE #798

45 yo Asian male w/ exertinoal calf pain and painful foot ulcers demonstrates hypersensitivity to intradermally injected tobacco extract. What pathologic process is responsible for pt's condition?

*Segmental vasculitis extending into continuous veins and nerves* Pt has *Buerger's Disease* (thromboangitis obliterans). He should be an assumed smoker b/c of the tobacco hypersensitivity reaction. Disease likes tibial and radial arteries. May see superficial nodular phlebitis and cold sensitivity (Raynaud's) -this disease pathology is similar to Giant Cell Arteritis #451

4,000 females were enrolled thru random selection to assess daily EtOH consumption w/ breast cancer incidence. At 5 yr f/u, 800 females were lost, esp those of moderate to heavy EtOH use. What bias is present?

*Selection Bias*: refers to system differences between groups in terms of tx response or px. A form of *Attrition Bias* where if there is a loss of subjects different in their risk of developing the outcome compared to the remaining subjects. #1188

Isoniazid mono therapy for TB would most likely result in what?

*Selective survival of bacterial cells secondary to gene mutation* *Isoniazid resistance* occurs by 2 selective gene mutations 1) decrease in bacterial expression of *catalase + enzyme* that is required for Isoniazid activity 2) Modification of protein target -Isoniazid mono therapy is only for PPD + and CXR -- TB -MOA: decrease mycolic acid synthesis #1225

82yo male c/o progressive dyspnea and fatigue and bilateral leg swelling for 1yr. PMH: HTN and on Amlodipine. Vitals: BP 122/72 and HR 55. PE: increased JVD w/ rapid 'y' decent and S4 heart sound. Abdominal PE: ascites. 3+ bilateral pitting edema. Echocardiogram: L atrial enlargement w/ LV hypertrophy and normal LV ejection fraction. Labs: normal. Endomyocardial biopsy: amorphous, acellular, light pink material. Dx?

*Senile Amyloidosis* Pt has *Diastolic HF* due to *Restrictive Cardiomyopathy*. W/ cardiac amyloidosis, this causes *ventricular hypertrophy. Cardiac amyloidosis* is due to: AL Amyloidosis, mutated transthyretin (familial ATTR), or wild-type transthyretin (*Senile Amyloidosis*). Congo red will be apple-green birefringent #94

How to calculate sensitivity!

*Sensitivity = TP/(TP + FN)* The ability of a test to correctly identify those *w/* a given disease

5 month old male w/ developmental delay and decreased activity relative to older siblings. PE shows inability to roll front to back and does not recognize parents. Labs show decreased Tetrahydrobiopterin Synthesis. What is deficient?

*Serotonin* is def. Pt. has *PKU* due to *BH4 deficiency* (required for Phe and Trp metabolism) secondary to *dihydropteridine reductase deficiency*. As a result, there is defective Phe and Trp metabolism. *Labs*: increased Phe and Trp; decreased Serotonin and Catecholamines. *Pres*: dev. delay, hypotonia, dystonia, and seizures. #1500

23yo male c/o 2mo hx of fatigue, malaise, and abdominal discomfort. He has hepatomegaly and increased liver enzymes. Never been vaccinated against hepatitis. Doesn't eat raw or undercooked foods. No sick contacts. Blood transfusion --. He immigrated to America 2yrs ago. Smokes 2ppd and drinks on weekends. Drugs --. Admits to several episodes of unprotected sex w/ different female partners in past year. What is present in his serum?

*Serum HBsAg* *HBV* is primarily transmitted via *sexual intercourse* (hetero- and homosexual), percutaneous, and vertical transmission. This *unvaccinated individual* w/ tender hepatomegaly and abnormal LFTs has acute HBV infection, which is characterized by *HBsAg* -remember: HBsAg means *infection*; anti-HBsAg means *vaccination or resolution* -note: while HCV can be transmitted via IVDU (or less commonly, sex) it is usually asymptomatic #386

1yo AA male c/o 3hr hx of severe swelling and tenderness of hands and feet. There is no known etiology but they are tender to the touch. Fam hx: older brother died of pneumococcal sepsis at 6yo. PE: bilateral, severe swelling of hands and feet. What lab is abnormal in this pt?

*Serum Haptoglobin* Pt has *Sickle Cell Disease*. Repeated sickling of RBCs causes *intra- and extravascular hemolysis*, increasing LDH and indirect bilirubin but decreasing haptoglobin. This is b/c haptoglobin binds free-floating Hb to prevent renal tubular injury -pt is in a sickle cell crisis right now #1855

What test should be conducted prior to administration of Amiodarone?

*Serum TSH* *Amiodarone* is 40% iodine by wt and may cause either *hypothyroidism or hyperthyroidism* -other labs: PFTs and hepatic transaminases -other SEs: QT prolongation, optic neuropathy, blue-gray skin discoloration, and peripheral neuropathy #625

What marker reflects osteoblast activity?

*Serum level of bone-specific alkaline phosphatase* #638

Shigella dysenteriae toxin

*Shiga toxin*: halts protein synthesis by disabling the 60S ribosomal subunit, leading to intestinal epithelial cell death and diarrhea

EHEC Toxin

*Shiga-like toxin*: inactivates 60S ribosomal subunit, inhibiting protein synthesis and eventual cell death

What are the independent effects of Simvastatin and Cholestyramine on hepatic cholesterol synthesis?

*Simvastatin* increases *Cholestyramine* no change *Statins* inhibit HMG CoA Reductase (HMG -> Mevalonate) resulting in decreased hepatic cholesterol synthesis. They then up regulate LDL receptors and increase LDL uptake. #165

25yo AAM receives a 5/6 HLA-matched kidney transplant. His immunosuppressive works by inhibiting lymphocyte proliferation by blocking IL-2 signal transduction. This medication is similar to what other drug?

*Sirolimus* *Sirolimus* fxs as a proliferation signal inhibitor by targeting *mTOR*. It works by *binding FKBP*, leading to *interruption of IL-2 signal transduction*, preventing G1->S progression, and lymphocyte proliferation #11786

Based on a graph w/ 2 variables (x-axis = insulin conc.; y-axis = glucose transporter expression), what cell type increases w/ glucose transporter expression w/ increasing insulin and which doesn't?

*Skeletal muscle cells and renal tubular cells*, respectively. Of the 5 major GLUTs, *only GLUT-4 is inducible by insulin* -GLUT-4 is found on *adipose and skeletal m.* -the others are insulin-independent #847

A pt w/ varicose veins is at increased risk for what?

*Skin Ulcerations* *Varicose veins* are dilated, tortuous veins typically involving *superficial veins* of the leg. *Increased intraluminal pressure or loss of vessel wall tensile strength* can lead to venous dilation and valve failure. This results in blood back flow and venous congestion. Common complications: chronic edema, *skin ulcerations*, poor wound healing, and infections -will not see pulmonary embolism b/c it only involves superficial veins, not deep veins -won't see intermittent claudication b/c that's caused by inadequate arterial blood flow #474

30yo female w/ GAD treated w/ Buspirone. Buspirone is associated w/ what?

*Slow onset of action* *Buspirone* is a *nonbenzodiazepine anxiolytic* for GAD and has a *slow onset of action*. Its a partial agonist on serotonin Rs. #247

43 yo male c/o palpitations provoked by anxiety. Described as sudden-onset pounding sensation tin the chest followed by light headedness and SOB. Syncope--. PMH and fam hx--. He's treated w/ Verapamil and reports improvement. What effect would Verapamil have on cardiac pacemaker cells?

*Slow spontaneous depolarization* Pt has *Paroxysmal SVT* and *Verapamil* works by *blocking L-type Ca+2 channels*, causing *slowing of phase 4 depolarization* (spontaneous depolarization) and reducing conduction velocity of SA and AV node -does also decrease myocardial contractility #1973

65 yo male c/o progressive wt loss, jaundice, and anorexia for last 3yrs. He notes that his urine has been dark and stools have been pale. PE: gallbladder is found to be enlarged and nontender. What is the most important risk factor?

*Smoking* Pt's sxs are consistent w/ *Pancreatic Adenocarcinoma* obstructing the common bile duct. #436

What cells are responsible for the formation of the fibrous cap in atheromas?

*Smooth Muscle Cells* *Atherosclerosis* is initiated by chronic hemodynamic stress and hyperlipidemia, which causes *endothelial cell injury*. This increases VCAM expression and *monocytes* migrate to the intimate. Cytokines and growth factors (PDGF, FGF, endothelin-1, and IL-3) promote *migration and proliferation of vascular smooth muscle cells* w/in the intimate. Smooth muscle cells produce *collagen* to form the *fibrous caps* of mature atheroma. Disruption of this cap is what causes thrombosis #443

40 yo female w/ R. knee injury. She's tx w/ opioid and knee pain decreases. Soon after administration, she has new-onset upper abdominal pain. Vitals normal. BMI 34. PE: tenderness over RUQ. Adverse drug effect on what structure is responsible for pt's condition?

*Smooth Muscle Cells* *mu opioids, morphine,* cause smooth muscle constriction in the *sphincter of Oddi*, leading to *spasm* and increased common bile duct pressure, increased risk for *Biliary Colic* -tx: admin NSAIDs #1258

55 yo male tx for depression ODs and presents to emergency department w/ severe confusion and hallucinations. Vitals: BP 80/60 and HR 100. His mouth is dry and face flushed. EKG: QRS prolongation and frequent premature ventricular beats. What would correct cardiac abnormality?

*Sodium Bicarbonate* Pt has *TCA Overdose*: delirium, seizures, cardiac abnormalities, severe hypoTN, and anticholinergic toxicity. Overdose caused *blockade of cardiac fast Na+ channels*. This calls for *Na+HCO3-* to increased serum pH, non-ionize the drug, and prevent blockade of fast Na+ channels #708

60 yo male found confused at home. Daughter found an empty bottle of Amitriptyline. No other meds. He's delirious and has visual hallucinations. He appears flushed. He has a brief seizure and is unconscious. Vitals: 99F, BP 70/40, and HR 120. Both pupils are dilated and equally reactive to light and his skin and mucous membranes are dry. EKG: QRS widening and QTc prolongation. Dies. Death is more likely related to what?

*Sodium Channel Inhibition* *TCAs* inhibit reuptake of NE and Serotonin for depression -they also *inhibit Na+ channel* conduction, slowing myocardial depolarization, and leading to *cardiac arrhythmias*--most common CoD w/ TCA overdose -may also see refractory hypoTN from decreased concentration and direct vasodilation, for mortality #574

46 yo male w/ treatment-resistant HTN. Workup for secondary HTN is unremarkable. PMH--. Enrolls in a trial long-acting tx that causes direct relaxation of smooth muscle of arterioles but not veins. What's the most likely SE?

*Sodium and fluid retention* *Selective arteriolar vasodilators* (ex: Hydralazine and Minoxidil) decrease BP and systemic vascular resistance. *Sympathetic activation*, via baroreceptor activation, limits these effects, causing *activation of RAAS* (Na+ and fluid retention) and *increase HR, contractility, and CO* #1252

How to calculate specificity!

*Specificity = TN/(TN + FP)* Ability of a test to correctly identify those *w/o* a given disease.

67 yo pt w/ nonischemic cardiomyopathy had a recent hospitalization for acute decompensated HF. PT's sxs improved w/ tx, but he has persistent SOB. PMH: HTN and hypercholesterolemia. Vitals: 115/70 and HR 66. PE: 3rd heart sound and mild lower extremity pitting edema. Echocardiogram: left ventricular ejection fraction of 30%. What diuretic would improve survival?

*Spironolactone* *Mineralocorticoid R. Antagonists* (Spironolactone and Eplerenone) prevent aldosterone from acting on distal renal tubules, causing increased Na+ and water excretion while sparring K+. They *improve survival* by blocking *deleterious effects of aldosterone on heart*, causing regression of myocardial fibrosis and *improvement in ventricular remodeling*. -should be used w/ ACEi and B-blocker to increase survival -contraindicated in renal failure and hyperK+ #686

6mo male delayed motor development He's weaker than the other kids and can barely roll side-to-side. PE: generalized hypotonia and decreased deep tendon reflexes. They discover a mutation on a protein involved in assembly of small nuclear ribonucleotides (snRNPs) in motor neurons. Pt has impaired fx of what cellular element?

*Spliceosomes* Pt has *Spinal Muscular Atrophy* due to mutation in *survival motor neuron (SMN1) gene*, which encodes *snRNPs* in lower motor neurons. Defective snRNPs results in *impaired spliceosomes and degeneration of anterior horns of spinal cord*. #2036

53 yo female w/ skin rash. 3wks hx of pruritic rash of worsening severity over posterior thigh. Has been exercising to lose wt and been applying a topical analgesic to thighs. PMH--. PE: erythematous rash w/ blisters, ulcers, and weeping drainage. What's found on skin biopsy?

*Spongiosis* Pt has *Eczematous Dermatitis*/*Acute Allergic Contact Dermatitis* (ACD) due to a *Type 4 Hypersensitivity*. Ag presentation via *Langerhans cells* to CD4 -ACD Histo: *Spongiosis* (accumulation of fluid in intracellular spaces of epithelium)--persistences causes plaque formation (acanthuses and hyperkeratosis) #1115

64yo male c/o several lesions on his forehead. Pt has been a gardener for most of his life. On palpitation, the lesion have a rough grainy texture. Biopsy: atypical keratinocytes w/ hyperkeratosis and parakeratosis. Pt's lesions make him at greatest risk for developing what?

*Squamous Cell Carcinoma* Pt has *Actinic Keratosis*, which are small, scaly, erythematous lesions w/ a *sandpaper texture* occurring on *sun exposed areas*. LM: *hyperkeratosis* (hyperplasia of stratum corneum), *parakeratosis* (retention of nuclei in stratum corneum), and *atypical keratinocytes*. May have pigment irregularities. AK *does not invade dermis* and in several yrs may progress to *invasive squamous cell CA*. #1993

73yo male c/o epigastric pain that starts 30-40 postprandial and does not respond to antacids. Pain is non-radiating and 6/10. Pt's lost 10 lbs in past few months b/c of fear of eating. No v/d or urinary sxs. PMH: HTN, hyperlipidemia, coronary bypass, and R-sided carotid endarterectomy. 32 pack yrs. Upper GI endoscopy --. The pt's underlying pathophysiology is most similar to what other condition?

*Stable Angina* *Chronic Mesenteric Ischemia* is consistent w/ *postprandial epigastric pain* w/ associated *food aversion/wt loss* in the setting of general atherosclerosis. His atherosclerosis involves mesenteric arteries, *decreasing blood supply*. This decreased blood supply is noticed postprandial b/c there's increased need for blood during digestion, inducing pain. This is *analogous to stable cardiac angina* b/c there's exercise-induced chest pain due to increased myocardial O2 demand. Dx via US. #414

57 yo female hospitalized for fever, chills, and RUQ pain. 104F. PE: abdomen shows rebound tenderness. Labs: increased alk phos. Imaging: fluid-filled cavity w/in R. lower lobe of liver. Which microbe/route combo is the cause of this pt's condition?

*Staphylococcus aureus by hematogenous route* The fluid-filled cavity in liver and sxs are suggestive of *Hepatic Abscess*. In *underdeveloped countries* these are *parasitic infections*. In *developed countries* these are *bacterial*. Pyogenic bacteria access liver via: 1) *Biliary tract infection* (ascending cholangitis)--caused by enteric G-- bacilli 2) *Portal tract infection* (bowel or peritoneal sources) 3) *Hepatic A.* (systemic hematogenous spread) 4) *Direct invasion from adjacent source* (peritonitis or cholangitis) #62

70 yo previously healthy male c/o abrupt onset fever, HA, myalgia, malaise, cough, and throat pain. His 2 granddaughters had similar sxs and missed a lot of school. PE: mild hyperemia and throat is w/o exudate. Pt sent home on conservative management. 5d later, he's admitted w/ c/o progressive dyspnea, chest pain, and productive cough. What pathogen caused this?

*Staphylococcus aureus* Pt initially had *Influenza A* but some pts may get secondary bacterial infection b/c of virally-mediated damage to mucocilary clearance of epithelium. -Top 3 bugs: *S. aureus, Streptococcus pneumoniae, and H. influenzae* #1666

38 yo male c/o abdominal discomfort and loose stools for 1yr. He lost 22lb despite normal appetite. Eats a balanced diet. No international travel, works as indoor office manager, and no sick contacts. PMH--. Vitals and PE normal. Labs normal. What is the next best step for assessment of malnutrition?

*Stool microscopy with Sudan III stain* *Generalized Malabsorption* is common due to defects in pancreatic secretion, mucosal disorders, bacterial overgrowth, or parasites. *Fats* are usually the first and most severely affected in GM, and *testing for fat malabsorption* is the most *sensitive* screening test. A qualitative assay w/ *Sudan III stain* will quickly identify unabsorbed fat and confirm malabsorption (stool show not have fat). #323

3 mo male w/ c/o slowly growing skin lesion on buttock. PE: brightened compressible plaques w/ sharply demarcated borders. Dx?

*Strawberry (Capillary) Hemangioma* Pt has a *Strawberry Hemangioma*, the most common benign vascular tumor in pediatrics. -typically regresses by 5-8yo -maybe found on liver -Histo: thin-walled blood vessels w/ narrow lumens #827

46 yo female w/ recurrent renal colic. Labs: increased Ca+2 and urinary Ca+2; decreased phosphorus. What change in bone structure is assoc. w/ pt's condition?

*Subperiosteal resorption w/ cystic degeneration* -"osteitis fibrosa cystica" Pt has *Primary Hyperparathyroidism*, often due to parathyroid adenoma. -classic sxs: bone pain, renal stones, psych disorder, and GI disturbance -"stones, bones, and groans" -"salt and pepper"=> skull HyperCa+2 via: 1) PTH-increases renal Ca+2 reabsorption 2)increased 1,25-D prod causes increased GI Ca+2 absorption. 3) PTH causes bone reabsorption via osteoclasts #631

Elderly pt w/ Shingles on chest. Pt did not receive initial tx b/c of delayed presentation. Shingles rash is gone but pain remains. She refuses systemic tx b/c of fear of SEs. She's started on topical Capsaicin and pain improves. Decreased activity of what NTs is associated w/ pt's pain relief?

*Substance P* Pt has *Postherpetic Neuralgia* due to sensitization of afferent fibers in dorsal horn -typically txed w/ *TCAs or anticonvulsants (gabalin)* -*nonsystemic*=> Lidocaine or Capsaicin (causes release and *depletion of Substance P* and also *defunctionalization of nociceptive Rs.*) #11680

72yo male c/o involuntary movements of his R arm for several hours. He was watching tv and all of a sudden he threw his remote. PMH: long-standing HTN and DM. PE: wild, large-amplitude, flinging movements affecting the proximal muscles of his R arm. What area of his brain is injured?

*Subthalamic Nucleus* *Subthalamic Nucleus* is a component of the *Basal Ganglia*. Damage will decrease excitation of globes pallidus internus, there by *reducing inhibition of thalamus*. This may result in *contralateral hemiballism*, a movement disorder characterized by wild, large-amplitude, flinging movements. This commonly occurs due to a *lacunar stroke*, which is associated w/ long-standing HTN and T2DM. #635

Homeless man is found to have a deficiency in Riboflavin. Activity of what enzyme in the TCA cycle and ETC is directly impaired?

*Succinate Dehydrogenase* *Riboflavin (B2)* containing coenzymes are key constituents in the *ETC*. B2 becomes phosphorylated into *FMN and FAD* to be apart of redox reactions. They're then reduced to *FMNH2 and FADH2. FMN* is an component of *complex I* and *FAD* is a component of *succinate dehydrogenase (complex II)*--seen in TCA and ETC #1807

43 yo male is w/o food for 3d and his liver begins to undergo gluconeogenesis from Alanine, lactate, and glycerol. As a part of this, Phosphoenopyruvate is made from Oxaloacetate in a reaction that requires a specific nucleoside triphosphate as a cofactor. What TCA cycle reaction synthesizes this?

*Succinyl-CoA->Succinate* The creation of succinate in the TCA cycle creates one *GTP* molecule and is then used by *PEP carboxylase* to convert PEP-> oxaloacetate #1022

Pt w/ COPD exacerbation needs to be intubated so they administer muscle relaxant X, but he remains apnea longer than expected. Assessment of neuromuscular blockade once, and again in 30mins, shows initial total and equal decrease in response; whereas, 30 mins later shows progressively decreasing response. What is relaxant X?

*Succinylcholine* *Depolarizing blockers (Succinylcholine)* have 2 phases. *Phase I Blockade*: prevents depolarization of motor end plate and shoes *equal reduction*, b/c presynaptic AChR stimulation mobilizes ACh vesicular release. *Phase II Blockade*: persistent exposure causes AChRs. to become *desensitized and inactivated*, causing a *fade*. -some pts are homozygous for atypical plasma cholinesterase and paralysis may last hours #1212

6 mo male w/ c/o lethargy and vomiting. Normal growth and development. Exclusive breastfeeding until 2d ago w/ pureed food. No fever or diarrhea. PE: pale, diaphoretic, and ill-appearing. Serum glucose 30 mg/dL. Confirmed Aldolase B deficiency. Remove what from diet?

*Sucrose* Pt has *Fructose Intolerance*, and *AR disorder* characterized by Aldolase B deficiency b/d of inability to convert *Fructose-1-P to DHAP* -*Sucrose->Fructose+Glucose* #1073

24 yo male w/ harsh systolic ejection murmur dies suddenly. Dxed w/ HCM. What most likely increased the intensity of pt's murmur?

*Sudden Standing* Pt has *HMC*, complicated by *L. ventricular outflow tract obstruction*, which caused his *harsh crescendo-decrescendo systolic murmur*. This murmur depends on *LV EDV*. Mechanisms that *decrease preload or decreased afterload* intensify HCM murmurs. This includes (decreasing preload): *sudden standing, Valsalva* (straining phase), or *Nitroglycerin administration* -increase preload/afterload decreases intensity: sustained hand grip, squatting, and passive leg raise #85

72yo male w/ long-standing dyspnea suddenly experienced an episode of syncope. PE: weak and slowly rising arterial pulses. There's a harsh systolic murmur best heard at R 2nd intercostal space w/ decreased intensity of 2nd heart sound. Diagnosed w/ aortic stenosis. 2mos later, he c/o palpitations and SOB. Vitals: BP 90/60 and HR 130 w/ irregularly irregular rhythm. EKG: new-onset A-fib. CXR: bilateral pulmonary edema. What hemodynamic change is associated w/ this pt?

*Sudden decrease in LV preload* *Severe Aortic Stenosis* has decreased CO b/c of valvular obstruction, which can be exacerbated by *loss of normal atrial contraction*. Atrial contraction is important b/c the heart most likely has undergone LV eccentric hypertrophy and therefore decreased LV compliance. This decreased atrial contraction causes *decreased LV preload* and may induce severe *hypoTN*. Will present w/ *acute pulmonary edema*. -no STEMI = no change in LV systolic fx #244

Pt was exposed to too much Nitroprusside. The reversal agent acts as a donor of which element to reverse condition?

*Sulfur* Pt has *Cyanide Toxicity* from *nitroprusside infusion*. Cyanide binds Fe+3 and prevents *cytochrome c oxidase* activity. Sxs: mental status change, seizures, lactic acidosis, and bright red venous blood. CN absorbs sulfur. *Sodium Thiosulfate* provides *sulfur groups* for rhodanese. -*Hydroxycobalamin*=> cobalt moiety binds intracellular CN and increases renal excretion -*Sodium Nitrite*=> promotes methemoglobin formation to bind CN #1254

63 yo male w/ long-standing osteoarthritis receives R total hip arthroplasty and acute postoperative course is unremarkable. F/u shows difficulty walking despite minimal pain. PE: pt leans to his R side when walking. When asked to stand on R leg, his L hip tilts downward. What nerve is injured?

*Superior Gluteal Nerve* *Superior Gluteal Nerve damage* is often mediated from hip arthroplasty or buttocks infections. It *innvervates* gluteus medius, gluteus minimus, and tensor fasciae latae muscles. These muscles *stabilize the pelvis and abduct the thigh*. Damage will cause *drooping of contralateral side* w/ standing on *affect leg* (*+Trendelenberg Sign*). *When walking*, the pt will *lean to ipsilateral side* to compensate for his hip drop (*Gluteus medius lurch*). #1639

63 yo female found to have R-adnexal mass. In surgery, the surgeon should ligate what structure during the oophorectomy to avoid excess bleeding?

*Suspensory ligament of the ovary* Ovaries are found posterolateral to uterus and are suspended by the mesoovarium superiorly ligament medially, and *suspensory ligament of the ovary* laterally. This ligament is a *fold in the peritoneum* and contains the *ovarian A., ovarian V., lymphatics, and nerves*--it arises directly from the abdominal aorta #1632

87 yo septic nursing home resident receive antibiotics and improves on 3rd day. PMH: stroke and dementia. Rhonchi are heard over lower R lung. CXR: dense air space opacities in superior region of R lower lobe. What is the etiology of hospitalization?

*Swallowing muscle dysfunction* *Hx of dementia and stroke* are risk factors for *Aspiration Pneumonia*. These will be found in superior region of lower lobe or posterior region of upper lobe. Most common causes: Peptostreptococcus sp., Bacteroides sp., Prevotella sp., and Fusobacterium sp. #2102

Nicotine Withdrawal

*Sxs*: dysphoria, irritability, anxiety, and increased appetite no PE

Stimulant Withdrawal

*Sxs*: increased appetite, hypersomnia, psychomotor retardation, and severe depression no PE

Alcohol Withdrawal

*Sxs*: tremors, agitation psychosis, anxiety, and *delirium* *Exam findings*: seizures, tachycardia, and palpitations

Benzo Withdrawal

*Sxs*: tremors, anxiety, perpectual disturbances, psychosis, and insomnia *Exam findings*: Seizures, tachycardia, and palpitations

1 yo male w/ bacterial meningitis due to indwelling cerebral shunt for his congenital hydrocephalus. Blood cultures: Coag -- Staphylococcus. What is the most important VF for this bacterium?

*Synthesis of an extracellular polysaccharide matrix* Pt is infected w/ *Staphylococcus epidermidis*, a *biofilm-forming* bacterium #8533

8yo male c/o severe dyspnea, tachypnea, and inspiratory stridor. He's also had worsening dysphagia for 2wks. Labs: increased blasts in periphery. These neoplastic cells normally give rise to what?

*T Lymphocytes* *Blasts* are highly suggestive of *leukemia*. Most common Pediatric leukemia is *ALL*. His *worsening dysphagia* can be explained by an *enlarging anterior mediastinal mass*, thus *T-ALL* would be most likely #1798

Equation for half life!

*T1/2 = (0.7 x Vd)/ CL*

How do PFTs change w/ increasing age? (TLC, FVC, and RV)

*TLC unchanged; FVC decreases; RV increases* -TLC is unchanged but RV takes over more of it -Vital capacity decreases -FRC increases #12100

68 yo WM w/ Giant Cell Arteritis. The morphologic changes in his As. are most similar to what other condition?

*Takayasu Arteritis* *Takayasu Arteritis* may present w/ *medial granulomas typically affecting aortic arch* and sometimes its branches. Predominantly in females <40yo. Its may have decreased BP and pulse in upper extremities compared to LEs. #452

67 yo male found dead at home w/o cause. Hx of HTN and MI 1 year ago. Gross exam shows LV hypertrophy. H&E sows fibrosis. The type of collagen present is similar to what other tissue?

*Tendon* -talkin about Type 1 collagen #8711

17 yo female has appendicitis. During surgery, what landmark is most helpful to identify the appendix?

*Teniae Coli* *Teniae Coli* is a longitudinal muscle that condense to form *3 distinct longitudinal bands and converges* at the rectosigmoidal junction at the root of the *appendix* #11782

Clostridium tetani toxin

*Tetanospasm*: protease that cleaves SNARE proteins for NTs. -blocks release of inhibitory NTs (GABA and Glycine)

In addition to appropriate dietary restriction, MSUD pts should be supplemented with what?

*Thaimine* *MSUD* is an *AD* disorder due to defective *branched-chain a-ketoacid dehydrogenase complex*, decreasing the metabolism of *Ile, Leu, and Val*. This enzyme requires 5 cofactors: *Thiamine, Lipoate, Coenzyme A, FAD, and NAD*. Some MSUD pts improve w/ high dose B1. #1336

A new drug is found to prolong survival in pts w/ stage 3 and 4 CML, w/o curing malignancy. If this drug is widely used, how would it change the number of incident and prevalent cases of CML?

*The number of incident cases will not change, the number of prevalent cases will increase* *Incident cases* represent *new cases diagnosed* in a time period. *Prevalent cases* are the *total number of cases* (both old and new) at a point in time #1171

34 yo female w/ a small bluish lesion under the nail of her R index finger. The lesion is extremely tender to touch. If the lesion is a tumor, its cells of origin are most likely to have what fx?

*Thermoregulation* A *bluish neoplasm under the nail* is either a *glomus tumor* or a *subungual melanoma*. B/c "pigmentation" was not an answer choice, it is not sublingual melanoma. *Glomus tumors* arise from *modified smooth muscle cells* that fx to *shunt blood away from skin in cold weather* and to *shunt blood toward skin to dissipate heat*. #467

Adult w/ 1 month hx of dyspnea, fatigue, weakness, and palpitations. Has not been taking care of himself for a year. PE: tingling and numbness of lower extremities, displaced PMI, 3rd heart sound, bilateral pitting edema, and bilateral lower extremity hyporeflexia. What nutrient is deficient?

*Thiamine* -required for decarboxylation of a-ketoacids Pt has *Wet Beri Beri*: peripheral neuropathy of distal extremities and cardiac involvement. #1047

32 yo female w/ c/o 6mos of persistent diarrhea. Has had 8-10 episodes/d of tea-colored, odorless, watery stools. Sxs persisted through lactose-free and fasting trials. No abdominal pain, fever, or vomiting. Afrebrile. Abdominal exam --. Gastric contents show lack of gastric acid secretion. Somatostatin tx relieves sxs. Excess of what hormone is responsible?

*Vasoactive Intestinal Peptide (VIP)* Pt has a *VIPoma* causing *watery diarrhea, hypoK+, and achlorhydria* (pancreatic cholera). -*VIP* increases pancreatic Cl- and HCO3- secretion, stimulating cAMP->diarrhea #1938

25 yo male c/o worsening abdominal pain, distention, and n/v for 3ds. He has 4yr hx of recurrent abdominal pain associated w/ diarrhea, low-grade fever, and easy fatiguability. Sxs tend to occur w/ stress. PMH: --. Vitals: 100.8F, BP 110/70, HR 104, and RR 16. BMI 19. PE: tender mass in RLQ of abdomen. Imaging shows small bowel obstruction. Laparotomy: abdominal mass is composed of inflamed small bowel that is adherent to mesentery and LNs. Mass is resected. What is seen on histology?

*Thickening of muscularis mucosae* The recurrent sxs plus the small-bowel obstruction makes *Crohn disease* likely. Crohn's is known for *transmural inflammation* w/ several complications: -*strictures and hypertrophy muscularis mucosae* leads to a *small bowel obstruction* -*fistulae* -*abscesses* #409

36 yo female c/o weakness, fatigue, and pallor. Denies heavy menses or melena. PE: conjunctival pallor. Labs: Hb 7.2 (low), RBC count 1.8 million (low), MCV 90, Reticulocytes 0.1% (low), Platelets 280,000, and WBC count 6,700. Fe+2, B12, and folate levels are normal. Bone marrow biopsy: absence of erythroid precursors. Further workup shows what?

*Thymic Tumor* Pt's anemia is b/c of *Pure Red Cell Aplasia*, which is due to *inhibition of erythropoietic precursors by IgG Abs or CD8 T cells*. This is associated w/ *Thymomas or Lymphocytic Leukemias*. Dx w/ chest CT. May also be assoc w/ Parvovirus B19 #1786

Researcher is studying hormone Rs. Receptor proteins isolated and one has a 30 aa motif containing a zinc molecule that's btwn 2 His and 2 Cys residues. Receptor for which hormone is described?

*Thyroid Hormone* A *zinc-finger* is associated w/ *DNA-binding domains*. Transcription factor use Zn+2 fingers. Only *intracellular Rs.* can act *directly as transcription factors*. They tend to be *lipid soluble* -all of the above applies to *Thyroid hormone* #11950

43 yo male w/ c/o painful muscle cramps. He also has tingling sensation around his mouth and intermittent sensation of choking in the throat. Vitals: BP 95/60 and HR 75. PE: appears comfortable but anxious. Light tapping on anterior ear elicits twitching of perioral muscles. What is a likely cause of pt's sxs?

*Thyroid Surgery* Pt has *Hypocalcemia* as seen w/ muscle cramps, perioral paresthesia, hypoTN, and possible larygnospasm. Signs: *Chvostek sign* (seen in vignette) and *Trousseau Sign* (prolonged inflation of BP cuff causes carpopedal spasm). *Neuromusclar hyperexcitability* happens when Ca+2 <7.0. -this pt's *parathyroid glands* were injured during thyroid surgery #1656

8yo Middle Eastern immigrant c/o low-grade fever and skin rash. Rash started on his face and spread rapidly down his body. Boy recently returned from Yemen. PE: generalized, fine, pinkish maculopapular rash and tender LAD bilateral behind his ears. What is the cause of disease?

*Togavirus* Pt has *Rubella*, an enveloped +ssRNA virus apart of Togaviridae. Its *rash spreads faster than Measles' rash* and does not darken or coalesce. Postauricular and occipital LAD is also common w/ Rubella #1669

46yo male w/ diet-controlled T2DM c/o substernal chest pain. PMH:-- for HTN. Fam hx:-- for CVAs. Exercise stress test: walks for 7min on treadmill and stops due to fatigue w/o chest pain. EKG: no abnormal changes. HR ranges from 70 to 132 at peak and meat BP ranges from 95 to 112. What parameter decreased at peak?

*Total Systemic Vascular Resistance* In exercise, the overall mean arterial pressure is much lower due to *an overall decrease in systemic vascular resistance*. This is b/c of arteriolar vasodilation in active skeletal muscles, which is mediated by Adenosine, K+, ATP, CO2, and lactate #1622

44yo homeless man found unresponsive. Hx of alcohol abuse. Vitals: 96F, BP 90/60, and HR 110. He's responsive only to pain and has dry mucous membranes. He's rehydrated, gains some mental status, but develops flank pain and decreased urine output. Renal biopsy: ballooning and vacuolar degeneration of PCT; multiple oxalate crystals present. What is the cause of renal failure?

*Toxic Renal Injury* Pt has *Acute Tubular Necrosis* b/c of *ethylene glycol poisoning*, as seen by the *oxalate crystals* -answer is not "prolonger hypotension" b/c this does not have oxalate crystals #887

Clostridium difficile toxins

*Toxin A*: recruits and activates PMNs, leading to release of cytokine that cause mucosal inflammation, fluid loss, and diarrhea *Toxin B*: induces actin depolymerization, leading to mucosal cell death, bowel wall necrosis, and pseudomembrane formation

8 yo male found to have endemic form of Burkitt Lymphoma. These translocated in these lymphoid cells produces a protein that is most directly responsible for what fx?

*Transcription Activation* *Endemic African form of Burkitt Lymphoma* is strongly associated w/ *EBV*. *Burkitt Lymphoma cells* are monomorphilic lymphocytes w/ prominent nuclei, multiple nucleoli, and vacuolated basophilic cytoplasms. *Tingible body macrophages* will be found on biopsy, along w/ a *"starry-sky appearance"*. Most Burkitt Lymphomas have a translocation btwn *c-Myc* on long arm *chromosome 8* and *Ig heavy chain* on *chromosome 4*. *t(8;14)*. c-Myc is a *nuclear phosphoprotein* that fxs as a *transcription activator* #1755

Researchers are looking at RTKs and their pathways. Their general pathway is: Binding growth factor-> autophosphorylation of tyrosine residues-> activation of phosphoinositide 3-kinase -> activation of protein kinase B (Akt) -> activation of X. What is the most likely direct effect of "X"?

*Translocation to the nucleus and gene transcription* #8632

Knockout of PECAM-1 gene would affect what PMN fx?

*Transmigration* 1)*Margination* 2)*Rolling*: PMN has loose binding of Silly Lewis to *L-selectin* on *PMNs* or *E-Selectin/P-selectin* on *endothelium* 3)*Activation*: slow rolling and induced conformational change in interns 4)*Tight adhesion/crawling*: PMNS bind their *CD18 B2 integrins (Mac-1 and LFA-1)* to endothelium's *ICAM-1* 5)*Transmigration/Margination*: *PECAM-1* -*Leukocyte Adhesion Deficiency*: absence of CD18 (no Mac-1 or LFA-1); recurrent skin infections w/o pus, delayed detachment of umbilical cord, and poor wound healing #8480

37 yo male has progressively enlarging cervical LN. Pt undergoes excision biopsy in L. posterior triangle of neck. At f/u, he has difficult w/ overhead activities. PE shoes a L. shoulder droop w/ weakness of L. arm abduction above horizontal. Other shoulder movements are normal. No sensory loss. What muscle is paralyzed?

*Trapezius* *CN XI damaged* and passes through *posterior trundle of neck* to innervate SCM and trapezius -fx: elevate scapula, rotate it, and stabilize shoulder -trapezius weakness: *shoulder droop*, impaired abduction of arm *above horizontal*, and winged scapula #11772

52yo female c/o 2mo hx of skin rash that worsens w/ sun exposure. She's become irritable, hostile, and had episodes of disorientation. Admits to chronic alcoholism. She has poor dietary intake and intermittent diarrhea. She restricts her diet for wt control. BMI 17. PE: hyperpigmented, scaly rash on hands, forearms, and upper chest. Its determined she lacks a precursor vitamin for NAD+ synthesis. The compensatory pathway to synthesize this coenzyme uses what as a precursor?

*Tryptophan* *Pellagra* is due to *Niacin (B3) deficiency* (diarrhea, dermatitis, and dementia). Niacin is an essential component of *NAD+ and NADP+* for redox reactions. Niacin can be obtained from dietary intake or *synthesized from Tryptophan*. -niacin deficiency is also seen in: Hartnup Disease, Isoniazid tx, and carcinoid syndrome #1064

What do you test prior to administration of Etanercept?

*Tuberculin Skin Test* *Etancercept* is a fusion protein derived from *Fc portion of IgG1 and TNF receptor* to inhibit TNF-a. This inhibition leads to decreased CMI and promotes reactivation of TB -Infliximab and Adalimumab are mAbs against TNF-a #720

32 yo male w/ multiple fractures and internal bleeding from MVA. Goes in OR for L femoral fracture fixation. BP 118/68 and HR 88. He develops oliguria on 2nd day of hospitalization. Renal biopsy: loss of columnar epithelial cells, denaturation of BM, interstitial edema, and epithelial vacuolization. What is the most likely outcome of pt?

*Tubular Re-epithelization* Pt has *Acute Tubular Necrosis* due to hypoTN from hemorrhage -1st 2 wks: oliguria, fluid overload, and electrolyte abnormalities (hyperK+ and metabolic acidosis) w/ stably decreased GFR and increase serum Cr #1053

Pt is found to be Influenza A +. In the infected cells, viral proteins are degraded and attached to MHC I and expressed on cell surface for CD8+. What enzyme is involved?

*Ubiquitin Ligase* *Ubiquitin Proteasome Pathway* is important for breakdown of native and foreign proteins. -proteins are degraded-> coupled to MHC I in ER #11674

17 yo male has c/o progressive proximal muscle weakness for the last several months. Meds--. Fam hx--. EM of a muscle biopsy shows sparse transverse tubules in some muscle fibers. What is the most likely consequence of muscle biopsy finding?

*Uncoordinated contraction of myofibrils within affected muscle fibers* *T-tubules* are *invaginations* of the *sarcolemma* and contain *v-gated L-type Ca+2 channels*. During muscle contraction, T-tubules allow the *depolarization impulse to rapidly propagate*, ensuring *Ca+2 release* from sarcoplasmic reticulum is uniform throughout the fiber and ultimately allowing for *synchronized contraction of myofibrils*. -decreased numbers causes *uncoordinated contraction* #824

63 yo male w/ c/o 1hr sudden onset chest pain that's not relieved by antacid. PMH: HTN, hyperlipidemia, and T2DM. Vitals: BP 100/60, HR 100, and RR 18. EKG shows ST-segment depression in inferior leads and cardiac Troponin T+. What anticoagulant is most effective in inactivating thrombin?

*Unfractionated Heparin* Pt has *Acute Coronary Syndrome*, as seen w/ +Troponin. Both *LMWH and unfractionated heparin* contain a pentasaccharide sequence that binds antithrombin, causes conformational change, and increases ability to inactivate Factor Xa. -only *unfractionated heparin* has the ability to bind thrombin and antithrombin (equal Xa and thrombin activity) -*LMWH* has created activity against Xa than thrombin. #2132

3yo male w/ abnormal development. Uncomplicated pregnancy and delivery. Normal development for first year of life. However, for the past 2 yrs, he's had progressive bilateral leg stiffness and abnormal involuntary muscle movements. Cognitive and motor development delay. Fam hx:--. Pt's wt, ht, and head circumference below 3rd percentile. PE: bilateral spastic paresis of LEs and frequent choreoarthetoid movements. Labs: increased Arginine in blood and CSF. The deficient enzyme normally produces what?

*Urea* Pt has *Arginase Deficiency*. This enzyme normally creates *Ornithine and Urea from Arginine*. Tx: *low protein diet* w/o Arginine. Unlike other Urea Cycle disorders, pts w/ Arginase Deficiency had *mild or no hyperammonemia* #1480

36 yo female received hysterectomy due to symptomatic uterine fibroid. The larger is found on the lower aspect of the uterus at the level of cardinal ligaments, compressing the bladder anteriorly. Postop, she has fever and R-sided back pain. She has been able to urinate w/o difficulty. What structure is causing pt's postop sxs?

*Ureter* Pt is able to urinate b/c second ureter is uninjured Water under the bridge!!! #11781

34 yo pregnant female comes in for f/u. Normal pregnancy to date w/ vitamins. Normal labs. Fam hx --. Detailed fetal US shows unilateral hydronephrosis. Male external genitals visible. If hydronephrosis is caused by obstruction, what is the most likely site?

*Ureteropelvic Junction* *Fetal Hydronephrosis* is primarily detected in second trimester. -most common pathologic cause of unilateral fetal hydronephrosis is narrowing of uteropelvic junction (if not dx prenatally, pt will have *palpable abdominal mass and enlarged kidney*) -hydronephrosis b/c of high compliance -females may have UPJ obstruction b/c of failure of canalization of ureteric bud #837

Serum makers for osteoclast activity?

*Urinary deoxypyridinoline*, TRAP, and urinary hydroxyproline

23 yo male w/ c/o recurrent blistering on back of hands and forearms for several yrs. They're normally small, itchy spots but they are becoming larger and heal w/ hyper pigmentation. OTC hydrocortisone and emollients didn't work. He's a night security guard. Drinks 2-3 cans of beer/d. PE: vesicles and erosions on dorsal of both hands. What enzyme is deficient?

*Uroporphyrinogen Decarboxylase (UROD)* Pt has *Porphyria Cutanea Tarda*, the most common heme synthesis disorder where to *lack UROD*. Typically manifests as *photosensitivity*, b/c of accumulation of *porphyrinogens* #1337

3d old female presents w/ persistent vomiting and refusal to feed. Vomiting has been greenish-yellow and does not contain blood. Infant appears dehydrated. Laparotomy: normal-appearing duodenum, absent jejunum and proximal ileum, and distal ileum winding around a vascular stalk. What intrauterine process is responsible?

*Vascular Occlusion* *Jejunal/Ileum intestinal atresias* are due to *vascular injury/occlusion* in utero, typically SMA. The distal segment assumes a *spiral configuration* and is known as an *apple peel" deformity -sxs: bilious emesis and abdominal distention #319

45yo male w/ hx of non-ischemia cardiomyopathy develops LV systolic dysfx is started on Milirone. What response will be seen?

*Vasodilation* *Milirone* is a selective *Phosphodiesterase-3 (PDE-3) inhibitor* that decreases rate of cAMP degradation (*+ ionotropy*). Milirone also works on *vascular smooth muscle* to increase cAMP, inducing *systemic arterial and venous vasodilation* #149

20 yo female c/o multiple burns on her hands. She burns them quite often b/c she says that she cannot feel when objects are "really hot." No PMH or sick contacts. Fam hx is significant for mom w/ MS. PE: diminished pin prick and temperature sensation along upper back, shoulders, and arms. Light touch, position, and vibration are preserved. Damage to what spinal cord area is responsible?

*Ventral White Commissure* Pt has a *Syringomyelia*, which primarily damaged ventral white commissure and ventral horns. The *spinothalamic tract* mediate *pain and temperature sensation*. Fibers travel: DRG-> Dorsal horn-> decussation in *ventral white commissure*-> contralateral lateral fasciculus-> VPL of thalamus-> primary somatosensory cortex of parietal lobe #503

What is the most likely CoD in a pt w/ acute MI from R coronary A occlusion on day 1?

*Ventricular Fibrillation* -this is the most common CoD of sudden cardiac death 48hrs after acute MI. ITs related to electrical instability due to lack of perfusion in the ischemia myocardium -A-fib may occur but it is not lethal #192

11yo male in for routine check-up. Fam hx: father died of "heart condition" 2yrs ago. Pt is 75th and 85th % for ht and wt, respectively. Vitals normal. PE normal. Cardiac: lower L sternal border has a harsh systolic murmur. Murmur intensifies w/ hand grip. What condition does this pt have?

*Ventricular Septal Defect* Pt has a *small VSD*, as seen by him being asymptomatic. *Handgrip* increases systemic vascular resistance and therefore *increases after load*, increasing the intensity of his murmur #2117

64 yo male w/ stable angina on Atenolol and Aspirin c/o worsening sxs. Doc adds a new medication. Several days later, he c/o severe dizziness. Vitals: BP 100/70 and HR 38. What is the new medication?

*Verapamil* B-blockers are using in stable angina to decrease myocardial O2 demand and target HR is btwn 55-60bpm. The significant decrease in HR implies added drug also has a *-- chronotropic effect*. When B-clockers and *Non-dihydropyridine Ca+2 Channel Blockers* are used together, there is an additive -- effect on HR, AV node conduction, and myocardial contractility -negative chronotropes: B-clockers (Metoprolol and Atenolol), non-dihydropyridine CCBs, cardiac glycosides (Digoxin), Amiodarone and Sotalol, and cholinergic agonists (Pilocarpine and Rivastigmine) #1776

56 yo female w/ c/o several ds of progressive dyspnea, productive cough, and fever. Son found her obtained and very SOB. PMH: HTN, T2DM, and Rheumatoid Arthritis. Exam shows bilateral pneumonia and severe RR distress. Pt is lethargic w/o focal neurologic deficits. Pt has emergent mechanical ventilation and started on broad spectrum antibiotics. Repeat exam 2hrs later shows areflexic, flaccid paralysis of all extremities. What caused her neurologic deficits?

*Vertebral Subluxation* *Long-standing RA* frequently involves the *cervical spine* and causes joint destruction w/ *vertebral subluxation/malalignment*. *Alantoaxial joint at C1* is most commonly affected b/c of high mobility. Unfortunately, *endotracheal intubation can acutely worsen* the subluxation and cause *compression of the spinal cord* and/or vertebral As., presenting as flaccid paralysis and areflexia. #11793

60yo female c/o persistent, profuse mucoid diarrhea. Despite not eating much for past 2d, her diarrhea has not decreased. No other sxs. Denies hx of colonoscopy. Fam hx:--. Tobacco and EtOH --. PE:--. Vitals normal. Labs: hypoK+ and microcytic anemia. Colonoscopy: 2.5 cm cauliflower-like mass on sigmoid colon. Dx?

*Villous Adenoma* *Villous Adenomas* are often large and sessile and can have velvety or cauliflower-like projections. These are the most likely to undergo *malignant transformation*. Adenomas tend to cause *Fe+2 deficiency anemia*. Villous Adenomas are known to secrete large quantities of watery mucous, leading to *secretory diarrhea*, hypovolemia, and electrolyte abnormalities. #430

42 yo Asian male is a known HBV carrier. Found to have a liver mass and increased serum AFP. Current condition is b/c of what?

*Viral DNA integration into host genome* Pt has *Hepatocellular CA* where *integration is the primary cause* -there's increased IGF II synthesis and IGF-1 R production #822

Researcher is studying antiretrovirals against HIV. She follows a protein that becomes glycosylated before being proteolytically cleaved into 2 smaller proteins in ER and Golgi. Based on this, what is the fx of these 2 newly formed HIV proteins?

*Virion attachment to the target cells* *env gene* is translated into a *polyprotein,* called *gp160*, that is glycosylated and cleaved into *gp120* and *gp41* -*gp120* mediates attachment to *CD4 R.* -*gp41* anchors gp120 via non covalent interactions #1672

What is Oseltamavir's MOA?

*Virion particle release* -it is a *neuraminidase inhibitor* and will cause vision buildup in cytoplasm; can also slow viral entry #1648

Deficiency of what vitamin w/ acute meseals infection is associated w/ a high rate of complications?

*Vitamin A* *Acute measles depletes Vitamin A stores*, increasing risk of *keratitis and corneal ulceration*. *Vitamin A supplementation*: prevents ocular complications, decreases risk of comorbidities, decreases recovery time, and decreases length of hospital stay #1045

45 yo WF c/o inability to walk. Spinal cord shows symmetric myelin layer vacuolization and axonal degeneration involving dorsal columns and lateral corticospinal trances. What is the cause of pt's condition?

*Vitamin B12 Deficiency* *B12 deficiency* causes abnormal myelin synthesis, leading to degradation of: 1) *Dorsal Columns*: bilateral loss of position and vibration senses; sensory ataxia 2) *Lateral Corticospinal Tracts*: UMN signs 3) *Axonal Degeneration of Peripheral Nerves*: numbness and paresthesias #65

16yo c/o progressive gait instability, dysmetria, and dysarthria for past several yrs. Can no longer play basketball. He's worried b/c his brother died of a neurodegenerative disorder at 21yo. PE: bilateral lower extremity weakness and loss of deep tendon reflexes, joint position, and vibration sensation. Brain MRI and spine: degeneration of posterior columns and spinocerebellar tracts. This disease pathology resembles what condition?

*Vitamin E Deficiency* *Vitamin E Def* is notable for hemolytic anemia and *neurologic dysfx* (b/c of free radical damage). Vitamin E def mimics *Friedrich Ataxia*, and AR disorder due to degeneration of spinocerebellar tracts and dorsal columns -distinguishing features: kyphoscoliosis, Diabetes Mellitus, and HCM (CoD) -this also kind of looks like B12 deficiency #671

Gut bacteria make what vitamins?

*Vitamin K and Folate* This is problematic b/c *small intestine bacterial overgrowth* increases folate and Vitamin K, causing nausea, bloating, abdominal discomfort, and malabsorption #11860

What is the most likely SE of Pioglitazone?

*Weight Gain And Edema* *Thiazolidinediones* (Pioglitazone) work by *decreasing insulin resistance* by *binding intracellular PPAR-gamma* and acting as a transcription factor to: increase FA uptake, increase Adiponectin, increase insulin sensitivity (liver and muscle), decrease TNF-a, and decrease leptin. They cause *fluid retention* by increasing Na+ reabsorption, which may *induce decompensation of CHF* #599

34yo immigrant from South Asian c/o heart palpitations that are prominent on the R. He notes that w/ moderate exertion, he has head "pounding" accompanied by involuntary head bobbing. Was diagnosed w/ murmur yrs ago. What do you suspect?

*Widening of the pulse pressure* Palpitations are b/c of forceful ventricular contractions ejecting large stroke volumes. Head pounding from unusually high amplitude pulsations of intracranial arteries. *Involuntary head bobbing* is a sign of *widening of pulse pressure*. These findings are consistent w/ *Aortic Regurg*. #238

35 yo female c/ end-stage renal disease secondary to T2DM. PMH: HTN, diabetic retinopathy, and neuropathy. Hemodialysis and EPO started 2mos ago. She takes daily long- and short-acting insulin, Lisinopril, and Calcitriol. Hb increased from 7.4 to 10.2 in 2mos. What complication may be seen from EPO tx?

*Worsening Hypertension* *EPO* is often used to tx *anemia of Chronic Kidney Disease*, which tends to happen around <30 GFR. SEs: increased risk of *thromboemolic events* (increased blood viscosity and RBC mass) and *HTN*. #11945

55 yo female w/ metastatic breast cancer is on an opioid analgesic for bone pain but sxs are worsening. Doc wants to increase her dose. Over the next few wks, she will most likely experience what SE?

*Worsening constipation* *Constipation* is the *most common SE of opioid use*. Further, tolerance to *constipation and meiosis* do not readily occur. #1257

What is the inheritance pattern of G6PD deficiency?

*XLR* #894

Researcher is studying the structure of a sarcomere. He develops mAbs that disrupt the binding of actin to structural support elements w/in sarcomere. What region do these mAbs bind?

*Z Line* *Z line* is the structural portion (super dark) -*thin filaments/actin*-> light area around Z line -*thick filaments/myosin*-> medium dark area btwn Z lines #1734

Inhibiting Arachidonic acid to LTs

*Zileuton* inhibits *5-lipooxygenase*, decreasing all LTs produced -good for asthma or allergic rhinitis

What short-term drug is the best for insomnia in the elderly and has least risk for addiction?

*Zolpidem* *Zolpidem* is a short-acting hypnotic that is structurally different from Benzos, but also *binds GABA receptors and enhances GABA inhibitory activity*. It has a *rapid onset of action* (about 15 min) and is metabolized by *liver P450 microsomal oxidases*. Half-life is 3hrs. -low potential for tolerance and addiction -no anticonvulsant activity -no muscle relaxing effects #349

22yo male c/o recurrent episodes of muscle weakness. PMH:--. Stable wt w/ BMI 23. Vitals: BP 190/110 and HR 70 w/o orthostatic hypoTN. Rest of PE --. Labs: very low renin. Overactivity of what structure is causing sxs?

*Zona glomerulosa of the adrenals* *Primary Hyperaldosteronism* is consistent w/ this pt (Adrenal hyperplasia or Conn Syndrome). *Aldosterone* normally increases absorption of Na+ and decreased absorption of K+ and H+ in CD. Aldosterone is secreted from glomerulosa and is *regulated by Angiotensin II and K+ levels*. Hyperaldosteronism causes: Na+ retention (*HTN*) and feed-back inhibition of RAAS (*very low renin*). Pts may develop *metabolic alkalosis and hypokalemia*. Symptomatic hypokalemia: *muscle weakness*, cramps, and arrhythmias #547

Med student injects Drug A into a pregnant dog and assesses the following parameters: BP, HR, pupil size, and uterine contractions. Studies show decreased uterine contractions and pupil dilation. What best describes "Drug A"?

*a and B adrenergic agonist* *Pupillary dilator muscle* of the eye contains *a1 Rs.and stimulation* will induce *contraction of muscle w/ subsequent dilation of pupil* (mydriasis) -ex: *Phenylephrine*, a selective a1 agonist *Uterine adrenergic Rs.* are *B2 Rs.* and stimulation leads to *uterine relaxation* (tocolysis). -ex: *Ritodrine and Terbutaline* are selective B2 agonists to prevent preterm labor #1368

Consumption of Alanine at the end of a 12hr fast period induces gluconeogenesis. But before it becomes glucose, its amino group is transferred to what?

*alpha-ketoglutarate* *Glutamine and Alanine* are important for movement of nitrogen through he body. *Glutamine* primarily regulates acid-base and cellular metabolism. Glutamine is converted by many tissues into Alanine, its especially excreted by skeletal muscle to remove excess nitrogen. *Alanine* goes to the *liver* to remove nitrogen and conduct *gluconeogenesis*. Alanine is then *transaminated* by alanine aminotransferase into *pyruvate* and the amino group is now transferred to *alpha-ketoglutarate* to form *Glutamate* #1369

Biologists are classifying proteins involved in various intracellular signaling pathways. A protein mixture from cell culture is electrophoresed and transferred to a filter membrane. Labeled ds-DNA probes are then used to detect a single protein of interest. What is most likely detected?

*c-Jun* *Southwestern Blot* is used to identify *DNA-binding proteins* (c-Jun) via *ds-DNA probes* #2044

Septic 84 yo male given IV NE for his hypotension. What cellular changes are likely to be seen as direct response to this medication?

*cAMP increase in cardiac muscle cells* *NE* is an adrenergic against that acts on a1, a2, and B1 receptors *a1 stimulation*: *vasoconstriction* to increase BP via *IP3 pathway* *B1 stimulation*: on the heart *increases cAMP concentration* via the *Gs pathway*, causing increased contractility, conduction, and HR *a2 stimulation*: *decreases cAMP* on pancreatic B cells #1367

Acanthosis Nigrans is due to what?

*increased FA lvl* Insulin resistance hinders antilipolytic effects of insulin on adipocytes -> lipolysis -> FFAs #1328

What is the initial step in pathogenesis of B-Thalassemia?

*mRNA formation* Pts w/ *B-Thalassemia minor* have increased HbA2. Common in Mediterranean population. There are alterations to B-chain production affecting *transcription, processing, and translation* of B-globin *mRNA*. Typically due to problems w/ splicing or chain termination #1940

76 yo female found to have Enterococcus derived vegetations on her mitral valve. An IV antibiotic is administered. Several ds later, she develops tinnitus and hearing loss attributed to this antibiotic. What does this antibiotic disrupt?

*mRNA genetic code reading* *Aminoglycosides* (Gentamycin) are used for *Enterococcal Endocarditis* and they're associated w/ *ototoxicity and nephrotoxicity*. In prokaryotes, Shine-Delgarno, a unique mRNA sequence found upstream of Aug, recognizes N-formylmethionine-tRNA and allows binding of 30S rRNA to form the *initiation complex*. *Aminoglycosides irreversibly bind 30S rRNA*, causing *genetic code misreading*. May also impact translocation #1488

24 yo male c/o abdominal pain, vomiting, and severe watery diarrhea after consuming wild mushrooms. PMH and meds--. PE: ill-appearing and jaundiced. Liver is soft, tender, and palpable 4 cm below costal margin. Labs: increased ALT, AST, and bilirubin. What is most likely directly inhibited by toxin?

*mRNA* *Amatoxins* from death cap mushrooms concentrate in the liver and bind *DNA-Dep-RNA-Poly* (RNA Poly II) to inhibit *mRNA synthesis*. -Can also cause acute renal failure by damaging PCT #8482

What labs are seen in a pt who overdosed on a bunch of Aspirin a little over 12 hrs ago? (pH, PaCO2, and HCO3-)

*pH 7.38, PaCO2 20 mmHg, HCO3- 12 mEq/L* *Acute Salicylate Poisoning* presents w/ n/v, dizziness, *tinnitus, fever, and tachypnea*. Will have: 1) *RR alkalosis* due to direct stimulation of RR center in medulla 2) *Anion gap metabolic acidosis* develops after 12hrs when salicylate increase lipolysis, uncoupling oxidative phosphorylation, and inhibiting TCA B/c this pt is >12hrs post-consumption, she has a *mixed RR alkalosis/metabolic acidosis disorder. pH* will be in *normal range*. *PaCO2* will be lower than expected b/c of concurrent RR alkalosis #1544

24 yo male lives at sea level and wants to climb a tall mountain. While hiking, he c/o lightheadedness, dyspnea, and fatigue. 2d later, he reaches peak. Never smokes, PMH--, and no fam hx. Arterial blood gas would show what?

*pH 7.46; pCO2 29 mmHg; pO2 57 mmHg* Pt has *High Altitude Sickness* due to decreased atmospheric pO2. Most cases go away in 2d. High altitude induces *hypobaric hypoxia, decreasing arterial pO2*. Hypoxia stimulates peripheral chemoreceptors to induce *hyperventilation*. Hyperventilation causes *RR alkalosis* (increased blood pH by loss of CO2) and *decreased pCO2*. B/c you're at *48hr*, *renal HCO3- excretion* compensates for alkalosis, stabilizing pH #12024

What lab findings are assoc. w/ SLE?

+ANA, anti-dsDNA, and anti-Smith Decreased C' Increased immune complexes #11798

Epispadias

Due to faulty position of *genital tubercle*, causing *dorsal* opening of penis

Incomplete recanalization of the fetal intestinal tract

Duodenal atresia Pres: bilious vomiting w/in 24hr of birth

DNA Poly I

5'->3' DNA Synthesis 5'->3' exonuclease activity--for excising RNA primers

Secondary Syphilis

5-10wks after chancre heals Presents w/ diffuse macular rash that encompasses palms and soles Condylomata Late are large gray wartlike growths on genital/perianal region

Androgen Insensitivity Syndrome

46 XY males who are phenotypically female -pretty much *hairless* -cryptorchid testes -no uterus or ovaries

Kleinfelter Syndrome

47 XXY w/ mild intellectual disability, gynecomastia, tall stature, small testes, and infertility

Sensorineural Hearing Loss

AC>BC bilaterally Weber lateralizes to unaffected ear

Carvedilol

B-blocker w/ a-blocking activity; not good for decompensated HF b/c CO is dependent on sympathetic tone -SEs: bradycardia, hypoglycemia, and fatigue

Junctional Nevi

Aggregates of nevus at dermoepidermal junction; black-brown pigmented macules w/ darker coloration in center; progresses to CMN

Terbinafine

Accumulated in skin, nails, and adipose -tx of Dermatophytoses

Dilation of sinusoids and perivascular hemorrhage

Acute venous obstruction w/in liver (Budd-Chiari)

Dysgerminoma

Adolescents Increased B-hCG and LDH "fried egg"

Tyrosinase Deficiency

Albinism

5a-Reductase Deficiency

Ambiguous genitalia in *male* b/c of decreased conversion of testosterone to dihydrotesterone *Female:* normal genitalia w/ normal BP and electrolytes

Human Bite

Anaerobes, Streptococci sp., or Eikenella corrodens (clenched-fist)

Spironolactone

Antagonizes Aldosterone on distal tubule and CD -SEs: hyperK+, gynecomastia, impotence, and decreased libido

Surface Ectodermal Dxs

Anterior Pituitary, lens, cortex, inner ear, olfactory epithelium, nasal and oral epithelium, and salivary, sweat, and mammary glands

Reactivation of HSV-1 occurs through what cell transport process?

Anterograde axonal transport via *kinesin* #1922

Myocardial Reprofusion Injury

Arrythmias, myocardial stunning, and myocyte death

Pulsus Paradoxus

Assoc. w/ *tamponade* and refers to decrease in SBP (>10mmHg) w/ inspiration. -limitation of R ventricular expansion b/c of fluid accumulation -IV septum bows towards LV-> decreased LV end diastolic volume and stroke volume.-> decreased systolic pulse pressure during inspiration

Intracellular hemosiderin

Assoc. w/ hemolytic anemia or frequent transfusions

Purkinje System

Assumes pacemaker in bradycardia -<40bpm

GFAP +

Astrocytes, oligodendrocytes, and ependymal cells

IL-5

B cell differentiation IgA production Eosinophil activity

GLUT-1

BBB and RBCs

Lithium labs

BUN, Cr, and Thyroid

Ciguatoxin (Moray eel) and Batrachotoxin (frogs)

Binds Na+ channels, keeping it open, and causes persistent depolarization

Ischial spine nerve block

Blocks Pudendal N. (S2-S4) for vaginal deliveries

Clostridium botulinum toxin

Blocks presynaptic release of ACh at the NMJ, resulting in flaccid paralysis

Capsofungin MOA

Blocks synthesis of glucan component of fungal cell wall -good for Candida sp. and Aspergillus sp.

Local Anesthetics

Blocks v-dependent Na+ channels -> decreased Na+ influx and AP propagation

Bordet-Gengou Agar

Bordetella pertussis

Rhizopus sp. morphology

Broad, ribbon-shaped, non-septated hyphae that branch at wide angles

B2 agonism

Bronchodilation, vasodilation, and tocolysis Rs found in smooth m. of airways, vasculature, and uterus

t(9;22)

CML BCR-ABL Tyrosine kinase activity

Foramen Rotundum

CN V2

Foramen Ovale

CN V3

Superior Orbital Fissure

CNs III, IV, V1, VI, ophthalmic V., and sympathetics

CYP Inducers

Carbamazepine, Phenobarbital, Phenytoin, Rifampin, Griseofulvin, St. John's Wort, Nevirapine, and Chronic Alcoholism

Primary Syphilis

Chancre A painless ulceration w/ raised, indurated borders Dissemination occurs at this stage

Nucleus Basalis of Meynert

Cholinergic neurons Decreased in Alzheimer's

NF1

Chromosome 17 Presents w/ cafe-au-lait spots, multiple neurofibromas, and lisch nodules

Progressive Mucosal Atrophy

Chronic Gastritis

CYP Inhibitors

Cimetidine, Ciprofloxacin, Erythromycin, Azole antifungals, Grapefruit juice, Ritonavir, Isoniazid, Acute Alcohol Abuse, Chloramphenicol, Sulfonamides, Omeprazole, and Metronidazole

Partial Hydatiform Mole

Clin features: vaginal bleeding, cramps abdominal pain, normal uterine size, and normal B-hCG. Path: focal trophoblast proliferation and fetal tissue present Karyotype: 69 XXX or XXY (*paternal or maternal*) IHC: *p57+*

Persistent Vitelline Duct

Connection btwn intestinal lumen and umbilicus at birth; meconium discharge from umbillicus

Superior Colliculus

Controls vertical gaze *Lesion*: upward gaze palsy, absent pupillary light reflex, and impaired convergence -dorsal midbrain

tPA

Converts plasminogen -> plasmin for fibrinolysis

Debranching Enzyme Deficiency

Cori Disease Hepatomegaly Ketotic hypoglycemia Hypotonia and weakness Abnormal glycogen w/ very short outer chains

Short arm chromosome 5 partial deletion

Cri du chat Round face, cat-like cry, and microcephaly

Impaired conjugation of bilirubin

Crigler-Najjar Syndrome and Gilbert Syndrome -indirect/unconjugated hyperbilirubinemia

Pigeon droppings

Cryptococcus neoformans

Drugs associated w/ osteoporotic fractures

Cyp-inducing anticonvulsants: phenytoin, phenobarbital, and Carbazamapine--increases Vit. D catabolism Aromatase inhibitors: decreases estrogen Medroxyprogesterone: decreases estrogen GnRH agonist: decreases testosterone and estrogen PPI: decreases Ca+2 absorption Glucocorticoids: decreases bone formation

Howell-Jolly Bodies

DNA inclusions found in asplenic pts

Supracondylar fracture w/ anteromedial displacement

Damages Median Nerve and Brachial Artery

Kallman Syndrome

Decreased GnRH synthesis -Primary amenorrhea, no secondary sexual characteristics, and olfactory defect

a2 agonism

Decreased generalized sympathetic outflow and decrease BP ex: Methyldopa and Clonidine Watch out for rebound HTN!

21-Hydroxylase Deficiency

Decreased glucocorticoid and aldosterone synthesis w/ increased androgen synthesis *Female*: ambiguous genitalia w/ hypoTN and hyperK+

ALA Synthase Deficiency

Decreased heme synthesis Hypochromic, microcytic anemia Requires B6

Bundle branch conductivity

Determines duration of QRS complex -Widened when blocked

B1 blockers

Decreases HR and contractility and blocks catecholamine-induced renin secretion Rs. found on cardiac and JG cells in kidney

What neurovasculature exits in anterior compartment of leg?

Deep Peroneal Nerve Anterior Tibial Artery and Vein

Bare Lymphocyte Syndrome

Defect in expression of HLA class II Ag on APCs -decreased CMI and HMI

Niemann-Pick Disease

Defect in sphingolipid degradation AR Increased sphingomyelin in monocytes cells Sxs: HSM, anemia, hypotonia, areflexia, and "cherry-red spot" on macula

Heinz Bodies

Denatured Hb in G6PD def.

Microabscesses at the tips of dermal papillae

Dermatitis herpetiformis

Polypeptide folding

Determined by aa's primary structure

Argatroban

Direct thrombin inhibitor for tx of heparin induced thrombocytopenia

Deficient bilirubin excretion into bile canaliculi

Dubin-Johnson Syndrome AR Absent biliary transport protein, MRP2 Dark liver Asymptomatic

LM: Focal Glomerulosclerosis

Dx: FSGS; IF: -- but maybe + for IgM and C3; EM: effacement of foot process

LM shows: Basement membrane splitting

Dx: Membranoproliferative glomerulonephritis; mesangial cell proliferation and increased mesangial matrix; IF: granular deposition; EM: spike and dome appearance in subepithelium

Cerebellopontine Angle

Dysfx of CN VIII presents as tinnitus and sensorineural hearing loss -vestibular schwannoma

Straight, short endometrial glands and compact stroma

Early proliferative phase of menstrual cycle -4-7d post menses onset

1st Pharyngeal Groove dxs

Epithelium of external ear canal

1st Pharyngeal Pouch dxs

Epithelium of middle ear and auditory tube

2nd pharyngeal pouch derivatives

Epithelium of tonsils crypts

Obstructive Lung Disease PFT pattern:

FEV1 <80% FEV1/FVC <70% FVC normal/decreased

Restrictive Lung Disease PFT pattern:

FEV1 <80% FEV1/FVC >70% FVC <80%

a-Galactosidase Deficiency

Fabry Disease; XLR Pres: cataracts, neurosensory findings, and angiokeratomas

Urachal Cyst

Failure of central portion of obliterate

Urachal Sinus

Failure of closure of distal urachus Periumbilical tenderness and purulent discharge from umbilicus

Acute Rheumatic Fever

Fatigue and heart murmurs associated with *untreated S. pyogenes pharyngitis*

Smooth phi thrum and thin vermillion border

Fetal Alcohol Syndrome

t(14;18)

Follicular Lymphoma bcl-2 gene and Ig Heavy chain Overexpression of apoptotic inhibitors

Dorsal bud of Pancreas

Forms tail, body, and rest of head

Ventral bud of Pancreas

Forms uncinate process and main pancreatic duct

Central Chemoreceptors

Found in Medulla Stimulated by decreased pH *PaCO2* is the major stimulatory factor b/c H+ cannot cross BBB but CO2 can and will form H+ on the other side

Posterior Circumflex A. Injury

Fracture of surgical neck of humerus damages A. and Axillary N.

Amifostine

Free radical scavenger that decreases nephrotoxicity assoc. w/ alkylating and platinum-containing chemo drugs

Biochemical characteristics of Staphylococcus epidermidis

G+ cocci, cat+, coag --, Novobicin +, and gamma hemolytic #679

Carcinoembryonic Antigen

GI (colorectal)

Endodermal Dxs

GI tract, liver, pancreas, lungs, thymus, parathyroid, thyroid, follicular cells, middle ear, bladder, and urethra

Restriction of Galactose

Galactosemia (AR) defect in Galactose-1-Phosphate Uridyltransferase Pres: neonate w/ jaundice, cataracts, hepatomegaly, and E. coli sepsis

Filgrastim

Granulocyte CSF for pts in neutropenia

Microglial Nodules

HIV Encephalopathy Dementia, slowed movement, and depression

Koilocytosis of the superficial epidermal layers

HPV

Pleural effusion on CXR

Hemithorax opacification w/o tracheal deviation.

Charcot-Bouchard Aneurysm

Hemorrhage of deep brain structures (basal ganglia, cerebellar nuclei, thalamus, pons...)

GLUT-2

Hepatocytes, pancreatic B cells, and renal tubular cells -has a ATP-sensitive K+ channel important for insulin release

Mississippi/Ohio River; bat/bird droppings; caves

Histoplasma capsulatum

Restriction of Methionine

Homocystinuria (AR) defect in cystathionin B-synthase -increased homocysteine and methionine

Hypertonic saline infusion and changes to ECF/ICF volume and mOsm

Hypertonic volume expansion Increased ICF and ECF volume Increased ECF mOsm Decreased ICF mOsm

Adrenal insufficiency and changes to ECF/ICF volume and mOsm

Hyposmotic volume contraction Super decreased ECF volume Decreased ECF and ICF mOsm Increased ICF volume (all b/c of NaCl loss)

Primary Polydipsia and SIADH and changes to ECF/ICF volume and mOsm

Hyposmotic volume expansion Decreased ICF and ECF volume Increased ECF mOsm (limited by aldosterone and ANP) Super increased ICF mOsm

What IL is responsible for IgM to IgE switching?

IL-4 is responsible for IgE secretion and predisposes to Type 1 hypersensitivity. Also stimulates TH0->Th1 #759

17a-Hydroxylase Deficiency

Impaired androgen and cortisol synthesis w/ *increased aldosterone synthesis* *Female:* normal genitalia *Male:* unvirilized/ambiguous genitalia sxs: HTN, hypoK+, and no puberty

Amantadine

Impairs uncoating/disassembly of Influenza A

Endodermal Sinus

Increased AFP Aggressive Schiller-Duval Bodies--resembles glomerulus

Systolic HF LV EDP, LV EDV, and LV EF

Increased LV EDP Increased LV EDV Decreased LV EF

Granulosa Tumor

Increased estrogen and inhibin Call-Exner Bodies and coffee bean nuclei

Pneumothorax on CXR

Increased lucency on affected side. Intrapleural air accumulation

Negatively skewed distribution

Increased number of observations w/ *smaller than expected magnitudes* that shift the curve to the *L* -*Mean<Median<Mode*

Triazoles MOA

Inhibits ergosterol synthesis ("-conazole")

Griseofulvin

Inhibits fungal mitosis at metaphase -tx of Dermatophytoses

Ricin

Inhibits protein synthesis by cleaving rRNA of 60S

Inferior Gluteal Nerve Damage

Innervates Gluteus maximus muscle Weakness w/ extension and external rotation Pt has difficulty rising from seated position

Dexrazoxane

Iron chelator that prevents Anthracycline-induced cardiotoxicity

Ring sideroblasts

Iron granules from defective heme synthesis -bone marrow

Chi2 Test

Is used to evaluate 2 categorical variables. i.e.: low vs high

Acute Hemorrhage and changes to ECF/ICF volume and mOsm.

Isosmotic volume contraction Decreased ECF volume Normal ICF volume Normal ICF and ECF mOsm Also seen in diarrhea

A-flutter ablation location

Isthmus btwn IVC and tricuspid valve

How would a point mutation in the TATA box effect a cellular protein's dogma?

It would disrupt *transcription initiation*. *TATA Box* is found about 25bp upstream of coding region. *RNA Poly II* binds *promoter region* for transcription (initiation) #2030

Histoplasma capsulatum prophylaxis

Itraconazole

Granuloma Inguinale

Klebsiella granulomatis Extensive and progressive ulcerative lesions w/o LAD Deep staining G-- intracytoplasmic cysts

Inability to close L eye

L VII lesion

Ablation for A-fib location

L. atrium near opening of pulmonary veins

Loading Dose Equation

LD = (Vd x Cpss)/Bioavailability Fraction

R 8th-11th rib organ

Liver

Cerebral Amyloid Angiopathy

Lobar hemorrhages (esp. elderly)

Type 4 collagen

Location: basement membrane Assoc. Disease: Alport Syndrome

Type 2 collagen

Location: cartilage, vitreous humor, and nucleus propulsus

Type 1 collagen

Location: dermis, bone, tendons, ligaments, dentin, cornea, blood vessels, and scar tissue Assoc. disease: OI

Type 3 collagen

Location: skin, lungs, intestine, blood vessels, BM, Lymph, and granulation tissue Assoc. disease: Ehlers-Danlos Syndrome

Hypertensive Arteriolar Sclerosis

Long-standing HTN predisposing occlusion of perforating branches of cerebral As. -Lacunar stroke

LTD4 R. Blocker

Monteleukast

DNA Mismatch Repair

Lynch syndrome (hereditary non-polyposis colorectal CA)

Bifid Scrotum

Malunion of *labiosacral folds* (these form labia majora in females)

t(11;14)

Mantle Cell Lymphoma cyclin D1 and Ig heavy chain G1->S phase

Arachnodactyly, Scoliosis, and Lens Displacement

Marfan Syndrome

Mitral valve prolapse and lens displacement are assoc. w/ what?

Marfan Syndrome

alpha (stats)

Maximal probability of making a Type I Error a research is willing to make

Obstruction of Cystic Duct

May result in *biliary colic* or *acute cholecystitis* No air present on Xray

Impaired ATP production during active muscle contraction

McArdle Disease

Glycogen Phoshorylase Deficiency

McArdle Disease Weakness and fatigue w/ exercise No increase in lactate after exercise

Pearson Correlation Coefficient

Measures the strength and direction of a linear relationship btwn 2 quantitative variables. ex: btwn HBA1C and average blood glucose levels.

Posterior Hypothalamic Nucleus

Mediates heat conservation

Anterior Hypothalamic Nucleus

Mediates heat dissipation

Lateral Hypothalamic Nucleus

Mediates hunger

Ventromedial Hypothalamic Nucleus

Mediates satiety

MEN 2a

Medullary thyroid cancer (calcitonin), Pheochromocytoma, and Parathyroid

Men 2b

Medullary thyroid cancer, Pheochromocytoma, and mucosal neuroma/marafanoid habitus

Mass of Posterior Fossa

Medulloblastoma Increased ICP and cerebellar dysfx (dizziness, ataxia, and nystagmus)

GFAP and Synaptophysin --

Meningioma

Ischemic Stroke 3-7d later

Microscopic changes: Macrophages/neuroglia invade

Ischemic Stroke 24-72 hr later

Microscopic changes: PMNs invade

Time is last drink EtOH Withdrawal Sxs

Mild withdrawal (6-24hr)=> tremors, anxiety, and insomnia Seizures (12-48hr) Alcoholic hallucinations (12-48hr) Delirium Tremens (49-96hr)=> confusion, agitation, fever, tachycardia, HTN, diaphoresis, and hallucinations

Enlarged villi and avascular edematous stroma

Molar pregnancy

Eosinophilic cytoplasmic inclusions

Molluscum contagiosum; pox virus

Vaginal Adenosis is assoc. w/ what?

Mom taking DES while pregnant

Cherry Hemangioma

Most common benign vascular tumor in *adults*; small and bright-red; dilated capillaries and post-capillary venules -doesn't regress

Non-small cell CA of lung markers

Mucin, EGFR, and KRAS

Cardiac Embolism

Multiple infarcts w/in different major vascular territories

Orchitis

Mumps, Chlamydia trachomatis, Neisseria gonorrhoeae, or Escherichia coli

Mesodermal Dxs

Muscles, connective tissue, cartilage, bone, serosa lining, blood vessels, lymphatics, spleen, internal genitalia, kidneys, ureters and adrenal cortex

Impaired NMJ transmission

Myasthenia Gravis -autoAb against ACh Rs

Locus Ceruleus

NE neurons Dorsal Pons Fight or flight

T Loop of tRNA

Necessary for binding of tRNA to ribosomes (TUC)

Sphingomyelinase Deficiency

Niemann-Pick Disease Pres: HSM, motor neuropathy, anemia, and macular cherry-red spots

Allopurinol

Noncompetitive inhibitor of xanthine oxidase -tx gout and prophylaxis against tumor lysis syndrome

Choledocholithiasis

Obstruction of *common bile duct* by gallstone. Leads to *pancreatitis* and/or cholangitis. *Cholangitis*: fever, RUQ pain, and jaundice. No air present on Xray

External Hemorrhoids

Occur below dentate line Drain into inferior rectal vein -> inferior pudendal vein -> internal iliac vein -caval system

Absence of corneal reflex

One of two lesion sites: 1) *V1 afferents* 2) *VII efferents*

Persistence of primary spongiosa in medullary cavity w/ no mature trabeculae

Osteopetrosis

Trabecular thinning w/ fewer interconnections

Osteoporosis

CA 125

Ovarian

Cat Bite

P. multicida (most common) or Bartonella henslae (lymphangitis)

Winter's Formula

PaCO2 = (1.5 x HCO3-) + 8 +/- 2

Disorganized lamellar bone structure in mosaic pattern

Paget's disease of bone

CA 19-9

Pancreatic cancer

Vitelline Sinus

Partial closure w/ opening at umbillicus

Acantholysis and intercellular IgG deposits

Pemphis Vulgaris -Ab against desmoglein 3

Vitelline Duct Cyst

Peripheral potions obliterate w/ central part intact

Mass of Dorsal Midbrain

Pinealoma/Germ Cell Tumor Causes obstructive hydrocephalus w/ increased ICP (HA, vomiting, and altered mental status) and Perinaud Syndrome (upward gaze palsy)

Transmural inflammation of the artery wall w/ fibrinoid necrosis

Polyarteritis Nodosa

Meta Analysis

Pooling of data from several studies

Imprinting

Prader-Willi and Angelman Syndromes (chr 15)

Decompensated Mitral Regurg Hemodynamics

Preload: increased Afterload: increased Contractile fx: decreased Ejection fraction: decreased Stroke volume: decreased -will see pulmonary edema b/c of decreased contractility

Compensated Mitral Regurg Hemodynamics

Preload: increased Afterload: no change Contractile fx: no change Ejection fraction: increased Stroke volume: no change

Congenital Diaphragmatic Hernia

Pres as severe respiratory distress, pulmonary HTN, and absent breath sounds unilaterally. -no limb or face deformities

Primary Carnitine Deficiency

Pres: muscle weakness, cardiomyopathy, hypoketonic hypoglycemia, and increased cytoplasmic muscle triglycerides

Hep A Reinfection

Presence of anti-Hep A IgM

What sxs/signs are unique to hyperthyroidism?

Pretibial myxedema (infiltrative dermopathy), exophthalmos, periorbital edema, and eye movement limitations. -note: very assoc. w/ Grave's #623

Mesna

Prevents hemorrhagic cystitis due to cyclophosphamide or ifosfamide

Anti-mitochondrial Abs

Primary biliary cirrhosis

Beta (stats)

Probability of committing a Type II error

IL-1

Prod. by Macs Endogenous pyrogen Differentiation of TH0 to TH1 and TH2

IL-12

Produced by Macs Increases population of TH1

IL-2

Produced by T cells when contacted w/ Ag Secreted primarily by TH1 Promotes differentiation of CD4, CD8, and B cells

IL-3

Produced by T helper cells Stimulates growth of BM stem cells

IL-10

Produced by TH2 Decreases population of TH1 Inhibits synthesis of IFN-g

Intradermal Nevi

Progression from CMN; intradermal nevus loses tyrosinase activity and produces no pigment; dome-shaped

Beat-to-beat variation in pulse amplitude

Pulses alternans is assoc. w/ LV dysfx

a1 blockers

Relax smooth muscle in A. and V walls, leading to decreased PVR. -good for HTN and BPH "-azosin"

Lateral Geniculate Body

Relays information to ipsilateral primary visual cortex *Lesion*: contralateral homonymous hemianopsia

Topo II/DNA Gyrase

Removes supercoils

Collecting Duct Cells renal cancer

Renal Oncocytoma Well-differentiated and multiple mitochondria

HSV latency is mediated via what cell transport process?

Retrograde axonal transport via *dynein*

Flumazenil

Reverses benzodiazepine toxicity

Extensive stromal fibrosis extending beyond the thyroid capsule

Riedel Thyroiditis Hard and non-tender

HCTZ SEs

SEs: hypok+, hypoNa+, hypoMg+2, and hyperCa+2

Supraoptic Hypothalamic Nucleus

Secretes ADH and Oxytocin

Paraventricular Hypothalamic Nucleus

Secretes ADH, CRH, Oxytocin, and TRH

Arcuate Hypothalamic Nucleus

Secretes Dopamine, GHRH, and GnRH

Case-Control Study

Selecting pts w/ disease (cases) and w/o disease (control) and then determining their previous exposure status

Berkson's Bias

Selection bias created by only choosing hospitalized pts as a control

L5 lesion

Sensory loss: booty, posterior lateral thigh, posterior lateral calf, and dorsal foot Weakness: foot dorsiflex and inversion, foot eversion, and toe extension

S1 lesion

Sensory loss: booty, posterior thigh and calf, and lateral foot Weakness: Achilles reflex, hip extension, knee flexion, and foot plantar flexion

L4 lesion

Sensory loss: lower anterior lateral thigh and knee, medial calf foot. Weakness: Hip adduction, Knee extension, and patellar reflex

L3 lesion

Sensory loss: lower anterior medial thigh Weakness: hip flexion, hip adduction, and knee extension

L2 Lesion

Sensory loss: upper anterior medial thigh Weakness: hip flexion

Progressive Supranuclear Palsy

Sequelae from Parkinsomism due to degeneration of midbrain and frontal subcortical white matter; vertical gaze palsy

Odansetron

Serotonin inhibitor to tx n/v in chemo tx

Direct Inguinal Hernia

Site of protrusion: Hesselbach triangle Lower border: inguinal ligament Medial border: rectus abdominus muscle Lateral border: inferior epigastric vessels -use pulp of finger

Indirect Inguinal Hernia

Site of protrusion: deep inguinal ring Lower border: inguinal ligament Medial border: inferior epigastric vessels -use tip of finger

L 9th-11th rib organ

Spleen

Saccular Aneurysm

Subarachnoid Hemorrhage

What neurovasculature exists in the lateral compartment of leg?

Superficial Peroneal Nerve

4th Pharyngeal Pouch dxs

Superior Parathyroid Glands Ultimobrachial Body

Brachial A. Injury

Supracondylar Fracture Anteromedial travel in arm

RNA Poly III

Synthesizes 5S rRNA and tRNA

RNA Poly II

Synthesizes mRNA, snRNA, and miRNA

Ethambutol

TB tx MOA: inhibition of arabinosyl transferase SEs: optic neuropathy

Isoniazid

TB tx MOA: inhibits mycolic acid synthesis SEs: neurotoxic (co-admin B6) and hepatotoxic

Pyrazinamide

TB tx MOA: unclear SEs: heptatotoxic and hyperuricemia

PCP and Toxoplasma gondii prophylaxis

TMP-SMX

Hexosaminidase A Deficiency

Tay-Sachs Infants w/ retinal cherry-red spots and loss of motor skills

Granulomatous inflammation of the media

Temporal Arteritis

Time constant

Time it takes for a charge in membrane to reach 63% of new value. -this increases in MS, bad :(

3rd pharyngeal pouch dxs

Thymus Inferior Parathyroid Glands

What neurovasculature exists in the deep posterior compartment of leg?

Tibial Nerve Peroneal Artery and Vein Posterior Tibial Artery and Vein

Renal Pelvis cancer

Transitional cell CA Forms papillary tumors

1st Pharyngeal Membrane dxs

Tympanic membrane

Stop Codons

UAA, UGA, and UAG

Nicotinic Cholinergic Blockers

Used for anesthesia to induce paralysis Rs. found on postganglionic sympathetic and parasympathetic skeletal m. at NMJ ex: Tubocuraraine

Multiple Logistic Regression

Used to predict the probability of a binary outcome based on one or more independent variables.

Muscle fiber inflammation and necrosis

Various myositises

Dilated Cardiomyopathy (Ventricular Wall Thickness, Ventricular Cavity Size, Contractile/Systolic Fx, and Diastolic Fx)

Ventricular Wall Thickness: N/decreased Ventricular Cavity Size: increased Contractile/Systolic Fx: decreased Diastolic Fx: normal

Ischemia Heart Disease (Ventricular Wall Thickness, Ventricular Cavity Size, Contractile/Systolic Fx, and Diastolic Fx)

Ventricular Wall Thickness: N/decreased Ventricular Cavity Size: increased Contractile/Systolic Fx: decreased Diastolic Fx: normal

HCM (Ventricular Wall Thickness, Ventricular Cavity Size, Contractile/Systolic Fx, and Diastolic Fx)

Ventricular Wall Thickness: increased IVS Ventricular Cavity Size: decreased Contractile/Systolic Fx: normal Diastolic Fx: decreased

Hypertensive Heart Disease (Ventricular Wall Thickness, Ventricular Cavity Size, Contractile/Systolic Fx, and Diastolic Fx)

Ventricular Wall Thickness: increased globally Ventricular Cavity Size: decreased Contractile/Systolic Fx: normal Diastolic Fx: decreased

Ribs 1-6 organ

Visceral Pleura

Excess unmineralized osteoid w/ widened osteoid seams. Osteoid matrix accumulation around trabeculae.

Vitamin D deficiency

Glucose-6-Phosphatase Deficiency

Von-Gierke Disease Impaire G-6-P -> Glucose Hepatomegaly and steatosis Fasting hypoglycemia Lactic acidosis Hyperuricemia and hyperlipidemia

Permissiveness (pharm)

What one hormone allows another to exert its max effect #551

Pygmalion Effect

When a researcher's beliefs in the efficacy of the tx can potentially alter the outcome

Misclassification bias

When either the exposure or outcome is not identified correctly (i.e.: using Peds BP cuff on adults)

Type II Error

When researchers fail to reject the null hypothesis when it is truly false ex: study finds that aspirin does not alter platelet production

Type I Error

When researchers reject the null hypothesis when the null hypothesis is actually true ex: candy improves HF mortality rate

Rugal Thickening and Hypersecretion

Z-E Syndrome

Neural Tube Dxs

brain and spinal cord, posterior pituitary, pineal gland, and retina

Abciximab

mAb that inhibits platelet aggregation by binding IIb/IIIa R.

GLUT-5

fructose transporter for spermatocytes and small intestine

Prostatic LN drainage

internal iliac LNs

L. Circumflex A. (Coronary A.)

lateral and posterior superior walls of LV

Epidermal Growth Factor

mitogenic influence of epithelium, hepatocytes, and fibroblasts

Sodium Nitrite

promotes methemoglobin formation to bind CN

GLUT-3

placental and neuronal

LAD (Coronary A.)

supplies: anterior 2/3 IVS, anterior wall of LV, and anterior papillary muscle

Tension Pneumothorax on CXR

tracheal deviation *away*

Ventricular Septum rupture post-MI

w/in 3-5d Acute ventricular septal defect and L->R shunting New holosystolic mumur

Papillary muscle rupture post-MI

w/in 3-5d Acute-onset severe mitral regurgitation Acute pulmonary edema

R. Marginal Branch A. (Coronary A.)

wall of RV and collateral circulation for LAD

Lead-time bias

when a screening test dxs a disease prior to natural occurrence.


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