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Flashcards in UWorld_3.15 Deck (21)
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1

Characteristics of G6PD Pathway

  • G6PD: G6P == .... ===> ribulose-5-P + 2 NADPH
  • NADPH ==> oxidative processes
    • FA, cholesterol
    • steroid synth
    • drug metabolism
  • ribulose-5-p ==> nonox processes
    • glycolytic
    • aromatic aa synth
  •  

2

HIV+ w/800 T cells + pneumo ==> causative agent?

s. pneumo

PCP common @ < 200 T cells

3

Mycoplasma pneumo ==> dx?

atypical pneumo 

4

Characteristics of drugs w/various volume of distribution

  • low Vd = 3-5 L
    • highly bound
    • charged
    • hydrophillic
    • high molecular weight
  • Vd = 14-16L = plasma + interstitial fluid
    • small molecular weight
    • hydrophillic
  • Vd = 41L = highest distribution
    • lipophillic (or hdyro)
    • uncharged

5

Where is the majority of water reabsorbed at nephron?

  • proximal tubule, regardless of patient hydration status

6

Implications of folate deficiency

  • thymidilate synthase: 5,10-MEtetrahydrafolate + dUMP ==> dihydrofolate + dTMP (deoxythymidine monophosphate)
  • folate deficiency ==> megaloblastic anemia and promotes erythrocyte apoptosis
  • supplementing with thymidine would decrease erythro apoptosis

7

Most potent cerebral vasodilator [blood gas]

pCO2

8

Aorta anterior and to the right of pulmonary artery ==> dx + embryologic cause?

  • dx = transposition of the great arteries (vessels)
  • due to failure of aorticopulmonary septum to spiral normally during septation of the truncus arteriosus

9

Embryology:

  • fail of proliferation ==>
  • fail of obliteration ==>
  • fail of migration ==>
  • fail of apoptosis ==>
  • fail of fusion ==>

 

  • prolif ==> fibular aplasia
  • obliteration ==> branchial cyst
  • migration ==> hirschsprung
  • apoptosis ==> overactive/autoreactive B/T cells ==> apoptosis
  • fusion ==> hypospadia

10

Factors used in the ddx of metabolic alkalosis

  1. urine chloride
  2. patient volume status
  • low urine chloride ==>
    • vomiting/ng aspiration
    • prior diuretic use
  • high urine chloride + hypo/euvolemia ==>
    • current diuretic use
    • barter or gittelman syndrome
  • high urine chloride + hypervolemia ==>
    • excess mineralocorticoids:
      • Cushings
      • ectopic ACTH
      • primary hyperaldo

11

Isoniazid: MOA

  • antimycobacterial
  • inhibits mycolic acid synthesis

12

Cell structure of mycobacteria that lead to acid-fastness

mycolic acids (loss of myc acid ==> loss of acid-fast)

13

Buspirone: MOA/properties, use

  • MOA: partial 5HTA1 agonist
    • no muscle relaxant
    • no anti-seizure
    • little hypnosis/hallucinatory
  • Use:
    • anxiety
    • esp. @ previous abusers of anxiolytics
      • less addiction potential vs. benzos

14

Consequences of Vit A abuse

  • ==> acute, chronic, teratogenic
  • acute = N/V
    • vertigo
    • blurred vision
  • chronic
    • alpecia
    • skin changes, dry skin
    • hepatomegaly
    • intracranial HTN (pseudotumor cerebri) ==> papilledema
    • vision difficulties
  • teratogenic
    • abortive
    • microcephaly
    • cardiac abnormalities

15

Beck's triad = 

  • hypotension
  • JVD
  • distant/muffled heart sounds
  • ==> cardiac tamponade

16

Recent viral illness + thyrotoxicosis, thyroid tenderness, reduced radioactive iodine uptake, elevated ESR ==> dx + histo features

  • subacute thyroiditis
  • mixed, cellular infiltrate w/occasional multi-nucleated giant cells

17

a1 receptors location + effect + drugs (agonists)

  • pupil sphincter ==> mydriasis (dilation)
  • bladder ==> sphincter contraction
  • peripheral blood vessels ==> increased SBP
  • agonists
    • norepi
    • epi
    • phenylephrine
    • methoxamine

18

beta-1 receptor locations + effects + agonist drugs

  • heart ==> increased HR, contractility
  • agonsits
    • epinephrine
    • dobutamine
    • dopamine
    • isoproteronol

19

beta-2 receptor locations + effects + agonist drugs

  • bronchi ==> bronchodilation
  • uterus ==> relaxation
  • skeletal muscle bood vessels ==> vasodilation
  • agonist drugs
    • isproteronal
    • terbutaline
    • ritodrine

20

unsteady gait, tremor + elevated transaminase + low ceruloplasmin ==> dx + tx?

  • dx = wilsons disease = excess copper @ liver, brain, eye
  • tx = penicillamine
    • chelation agent

21

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