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Flashcards in UWorld_3.21 Deck (25)
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1

Mutations associated with Alzheimer disease

  • Early onset (<60 yo)
    • Amyloid precursor protein (APP) @ chromosome 21
    • Presenilin 1 @ chromo 14
    • Presenilin 2 @ chromosome 1
  • Late-onset
    • Apolipoprotein E`4

2

Contraindications for use of OCPs

  1. Prior thromboembolic event/stroke
  2. hx of estrogen-dependent tumro
  3. women > 35 who smoke heavily ==> higher risk of CV events
  4. hypertriglyceridemia
  5. decompensated or active liver disease
  6. pregnancy

3

Gross painless hematuria @ older adult ==> dx?

  • urothelial cancer until proven otherwise
  • most common = clear cell carcinoma <== renal tubular cells
    • high glycogen or lipid content on histologic prep

4

RCA occlusion ==> dx + EKG findings?

LAD occlusion ==> dx + EKG findings?

LCX occlusion ==> dx + EKG findings?

  • RCA ==> transmural ischemia @ inferior wall of L ventricle ==> ST elevations @ II, III, aVF
  • LAD ==> anteroseptal transmural ischemia ==> ST elevation @ V1-V4
  • LCX ==> lateral wall transmural ischemia ==> ST elevation @ V5, V6 & possibly I and aVL

5

Locations of ovarian artery

Location of uterine artery

  • ovarian a. w/in suspensory ligament
  • uterine artery w/in transverse cervical ligament

6

Calculating A-a gradient @ sea levle

  • A = PAO2 = 150 - (PaCO2/0.8)
  • a = PaO2
  • Normal A-a < 10-15

 

7

Risk factors for gallstone formation

  • "fat, fertile, female, forty"
  • OCPs/Pregnancy ==> increased estrogen and progesterone
  • estrogen ==> upregulated HMG-CoA reductase activity ==> supersaturation of bile with cholesterol
  • progesterone ==> gallbladder hypomotility

8

Pulsus Paradoxus ==> Ddx?

  • = decrease in systolic BP > 10 mmHg w/inspiration
  • acute cardiac tamponade
  • constrictive pericarditis
  • severe obstructive lung disease
  • restrictive cardiomyopathy

9

Microbio characteristics of Corynebacterium

  • gram (+) rods
  • non-motile, unencapsulated
  • clumps ~ chines letters or V- or Y-shaped chains
  • cytoplasm has metachromatic granules that stain w/aniline dyes

10

RBF calculation

= PAH clearance / (1-Hct)

11

S. pyogenes microbio characteristics

  • gram + cocci in chains
  • b-hemolytic
  • susc. to bacitracin
  • pyrrolidonyl arylamidase (PYR) positive

12

Post-influenza bacterial pneumonia causes

  • s. pneumo
  • s. aureus
  • h. influenzae

13

Role of "P bodies" in cell

  • cytoplasmic proteins that play a role in mRNA translation regulation and mRNA degradation

14

Causes of exacerbation of mysathenia gravis

  • myasthenic crisis = undertx <==ephodrium will improve sx
  • cholinergic crisis = overtx <==ephodrium will not improve sx

15

Consequences of HCV infection

  1. acute hepatitis (+/-)
  2. chronic hepatitis
  3. slowly progressive to cirrhosis

16

Serotonin precursor amino acid

tryptophan

17

Glutamic acid ==> molecular product?

Histidine ==> molecular product?

Methionine ==> molecular product?

Tyrosine ==> molecular product?

  • glutamic = GABA
  • histidine = histamine
  • methionine= cysteine, carnitine, taurine, lethicin
  • tyrosine = thyroxine, dopamine, epinephrine, norepi, melanin

18

Antidote for serotonin syndrome

  • cyproheptadine = antihistamine + anti-serotonergic properties

19

Verapamil: MOA, use, SE

  • MOA = non-dihydropyriddine ca-channel blocker
    • slows conduction through AV nodes
  • use = rate control in afib w/rapid ventricular response
  • SE
    • constipation
    • gingival hyperplasia
    • bradycardia
    • first, second, or third degree AV node block

20

Leoprolide impact @ male

  • GnRH
  • transient increase, then decrease in both T and DHT

21

Vancomycin: MOA vs. Ceftriaxone: MOA

  • Vanc binds D-ala (glycoproteins @ cell wall of bacteria)
  • Ceftriaxone binds PBPs
    • PBPs = transpeptidases that cross-link peptidoglycan @ cell wall

22

Most common cause of nephrotic syndrome in children

  • MCD = fusion of foot processes on EM

23

Watershed areas of the colon

  • splenic flexure and distal sigmoid colon
  • lie between major arteries ==> susc. to damage during hypotension/low perfusion states

24

Lead placement in biventricular pacemaker

  • 2-3 leads used
  • first two = @ RA and RV via subclavian/SVC
  • left ventricle pacer lies @ atrioventricular groove

25

Characteristics of lac operon

  • genetic sequence in E. Coli that codes for proteins requried for metabolism of lactose
  • regulatory gene (i), promotor region (p), operator region (o) + three structural genes (z, y, a)
    • z = beta-galactosidase ==> lactose ==> glucose + galactose
    • y = transmembrane enzyme allows cell perm. to lactose
    • i = repressor protein ==> w/out lactose binds operator and prevents RNA pol binding to promotor
  • lactose assoc. w/repressor ==> release of repressor ==> trxn of lac operon
  • glucose ==> decreased aden cyclase ==> decreased cAMP ==> decreased expression of lac operon genes

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