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Flashcards in UWorld_3.28 Deck (32)
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1

DiGeorge due to...?

malformation of third and fourth pharyngeal pouch

2

Prevention measures for acute organ rejection

-calcineurin inhibitors -corticosteroids

3

Bio active form of pantothenic acid = ?

coenzyme A

4

Rxn that requires coA

OAA ==> citrate (first step of Krebs cycle)

5

Steps in active vit D synthesis

1. sunlight catalyzes first rxn: 7-dehydrocholesterol ==> cholecalciferol 2. @ liver: cholecalciferol ==> 25-hydrocholecalciferol 3. @ kidney: 25-hydrocholecalciferol ==> 1,25-dihydrocholecalciferol [1-alpha hydroxylase] 4. @ vit D excess ==> @ kidney: 25-hydrocholecalciferol ==> 24,25-dihydrocholecalciferol = inactive form [24-alpha hydroxylase]

6

How does EBV enter B cells?

attaches to CD21 = cellular receptor for C3d complement component via gp350

7

Process of PAH secretion @ proximal tubule

-taken up by endothelial cells and secreted into filtrate -accomplished via carrier-mediated transport

8

Mechanism + testing for mushroom poisoning

-amatoxin (e.g. death cap toxin) ==> inhibition of DNA-dependent RNA pol II ==> inhibited mRNA production ==> apoptosis -test = alpha-amantin levels @ serum

9

Cystinuria presentation/mechanism

-defect in transporter of ornithine, lysine, arginine, cystine - ==> nephrolithiasis/renal colic in teens-20s -hexagonal cystine crystals

10

Histo appearance of carcinoid tumors

nests or sheets of cells w/eosinophillic cytoplasm + round/oval stippled nuclei

11

Trazadone: use, SE

use: sedation for insomnia w/depression in conj. w/SSRIs SE: priapism (extended erection)

12

Venlafaxine: drug category

SNRI

13

Active vs. Inactive RB

-active = hypophosphorylate ==I G1/S transition -inactive = hyperphosphorylated

14

Histoplasma endemic locations

Ohio & MS river basins; found in bird and bat droppinga

15

Most important risk factor for development of intimal tears ==> aortic dissection

HTN

16

Anaplastic definition/characteristics

Anaplastic = cells w/complete lack of differentiation 1. loss of polarity/complete disorganization; e.g. sheets 2. variation in cell/nuclear shape and size (pleomorphism) 3. high N-C ratio w/hyperchromic nuclei & clumped chormatin 4. numerous, abnormal mitotic figures 5. giant cell formation

17

First vs. Second Generation Anti-Histamines + examples

-first gen= hydroxyzine, promethazine, chlorpheniramine, diphenhydramine ==> antiH1 + SE: antimusc + anti-serotonergic (increased appetite) + alpha-adren (postural hypotension) -second gen = fexofenadine, cetirazine ==> much less SE/sedation

18

Kussmual sign

-paradoxically elevated JVP during inspiration (normally decreases) <== due to restriction in RV filling capacity -sign of constrictive pericarditis

19

Characteristics of drugs w/primarily hepatic clearance

high lipophillicity & Vd

20

Homeobox ==>

transcription factors

21

Causes of upper quad/low quad hemianopsia

upper quad = contralateral temporal lesion ==> disruption meyers loop = fibers carrying contralateral visual field upper quadrant vision (#4) lower quad = contralateral parietal lesion ==> disruption of fibers carrying contralateral visual field lower quad vision (#5)

22

Hypo- or hyper-pigmented patches that are more visible after tanning ==> dx?

  • Pityriasis versicolor <== Malassezia furfur
  • ==> Spagghetti and meatballs appearance on KOH prep

23

Important allosteric activator of gluconeogenesis

  • [@mito] Acetyl-CoA stimulates pyruvate carboxylase: Pyruvate ==> OAA
  • [@mito] OAA ==> malate ==> cytosol
  • [@cytosol] malate ==> OAA ==> PEP [via PEPCK]

24

Molecular stimulators of PMN chemotaxis

  • IL-8 <== produces by macrophages
  • C5a = complement = also chemotaxis for eosinophils, monocytes, and basophils
  • LTB4

25

Histone characteristics

  • H1 = non-core ==> increased packaging w/linkage of nucleosome
    • H2A, H2B, H3, H4 = nucleosome core proteins

26

Sudden, severe headache w/out focal neurologic deficits ==> sx?

  • subarachnoid hemmorhage <== commonly due to rupture of berry aneurysm @ COW
  • assoc. w/ED, ADPCKD

27

Hepcidin role/source

  • Hepcidin = APR produced by liver parenchyma = major control of iron homeostasis
  • Hepcidin ==> internalization of ferroportin on cells ==> decreased intestinal iron absorption + inhibition of iron release by macs

28

Most common cause of fatigue + new-onset murmur in young adult

bacterial endocarditis

29

Commonly used drugs in MRSA infections + MOA

  • Vancomycin: binds D-ala-D-ala subunits ==> prevents membrane formation
  • Daptomycin: disrupts cell membrane through formation of transmembrane channels
  • Linezolid: inhibits protein synthesis by binding 50S subunit

30

SE:

Vancomycin

Daptomycin

Linezolid

 

  • Vanc = Red man; nephrotoxicity
  • Daptomycin = myopathy & CPK elevation
  • Linezolid = thrombocytopenia, serotonin syndrome, optic neuritis

31

Formulas for calculating CO

  • CO = SV x HR
  • CO = O2 consumption/arteriovenous O2 difference

32

Cardiac tissue conduction velocity

  • Fastest to slowest:
  • Purkinje
  • Atrial m.
  • Ventricular m
  • AV node
  • "Park At Ventura Ave"

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