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USMLE Step 1 > Rx_2.3 > Flashcards

Flashcards in Rx_2.3 Deck (22)
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1

Characteristics of vWD

  • autosomal dominant
  • deficiency/dysfxn of vWF
  • vWF = platelet adhesion + carrier molecule for factor VIII ==>
    • reduced ristocetin-induced platelet aggregation
    • prolonged partial thromboplastin

2

Trinucleotide repeat diseases

  • CAG @ chromosome 4 = Huntington's
  • GAA @ chromosome 9 = Friedrich's ataxia
  • CTG @ chromosome 19 = Myotonic dystrophy
  • CGG on X chromosome = Fragile X

3

Drug used to prevent NSAID-induced gastric ulcers + MOA

  • misoprostol = prostaglandin E1 analog
  • NSAIDs ==: inhibition of prostaglandins ==> increased acid secretion/reduced bicarb/reduced mucous barrier ==> ulcer
  • misoprostol acts as a prostaglandin and antagonizes these effects and prevents ulcers

4

Misoprostol: uses + SEs

  • uses
    • prevention of NSAID-induced ulcers
    • maintain PDA
    • medical termination of pregnancy (w/mifepristone)
  • SEs
    • induction of labor
    • uterine cramps

5

Genetic problem/mutation ==> cystic fibrosis

  • deletion of phenylalanine on chromosome 7

6

Genetic problem/mutation ==> duchenne's muscular dystrophy

  • frame-shift mutation = nucleotide insertion or deletion ==> altered reading frame
  • X chromosome 

7

Genetic problem/mutation ==> sickle cell

  • missense mutation: glutamic acid substitued for valine

8

FAP results from ....?

  • mutation in APC gene on chromosome 5

9

Abnormality on chromosome 11 = ?

wilms' tumor

10

Abnormality on chromosome 13 = ?

  • retinoblastoma
  • osteosarcoma

11

Abnormality on chromosome 22 = ?

  • neurofibromatosis type 2

12

Peaked T waves on ECG = ?

hyperkalemia

13

Common cause of hyperkalemia in pt/ w/HTN

pottasium-sparing diuretic, e.g. Spironolactone

14

Cimetidine: MOA, SE

  • MOA = H2 antagonist
    • used to tx ulcers
  • SE
    • headache, confusion
    • thrombocytopenia
    • inhibition of cytochrome P-450 system
    • anti-androgen effects 
      • increased prolactin ==>
      • gynecomastia
      • impotence
      • decreased libido

15

Characteristics of I-cell disease

  • failure to phorphorylate mannose residues ==> mannose-6-phosphate ==>
    • exocytosis of enzymes that should be targeted to the lysosome
  • ==> intracellular inclusion that are not properly degraded by lysosomal enzymes

16

Diabetic meds that ==> hypoglycemia

  • any med that increases/promotes insulin secretion can lead to hypoglycemia
  • e.g.
    • insulin = IM injection
    • sulfonylurea drugs
      • glyburide = oral

17

Acarbose: MOA, use, SE

  • MOA: inhibits intestinal brush-border alpha-glucosidase (prevents release of glucose from starches/disaccharides)
  • use: T2D antihyperglycemic drug
  • SE: GI disurbance

18

Exenatide: MOA, use, SE

  • MOA: glucagon-like peptide 1 (GLP-1) agonist
    • delays gastric emptying and enhance's glucose-dependent insulin secretion
    • subq administration
  • use: T2D
  • SE
    • not associated w/hypoglycemia when used alone
    • GI disturbance
    • increased risk of pancreatitis

19

Metformin: MOA, use, SE

  • MOA: not exactly known, may decrease gluconeogenesis and increase insulin sensitivity
  • use: FIRST LINE in T2D
  • SE
    • few adverse effects
    • contraindicated in renal failure (==> lactic acidosis)

20

Liver polypeptides enter circulation @ ...?

hepatic vein

21

Sore midline neck mass in child ==> dx?

  • infected thyroglossal duct cyst
  • result of peristent pathway between site of thyroid embryo development (primitive pharynx) and eventual location in neck
  • duct normally involutes, but may remain and become infected

22

Polymyxins: MOA, use, SE

  • MOA: destroy gram-negative bacteria by binding cell membrane phospholipids and acting as a detergent
  • Use: severe gram-negative infections resistant to less toxic antimicrobials
  • SE
    • numbness @ extremities
    • nephrotoxocity
    • dizziness
    • drowsiness, confusion
    • nystagmus, blurred vision

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