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Flashcards in UWorld_3.4 Deck (19)
1

IF/EM microscopy in Berger's disease

  • Berger = IgA nephropathy
  • ==> IgA deposits @ mesangium on IF
    • electron dense material on EM

2

Berger's + extra-renal sx ==> dx?

  • Henoch-Schonlein disease
  1. skin = purpuric lesions on extensor surfaces of arms, legs, buttocks
  2. GI = abdominal pain, N/V, intestinal bleeding and intussusception
  3. rena = IgA nephropathy

3

Psych terms:

Acting out =

Isolation = 

Undoing = 

  • acting out = immature defense mechanism; e.g. throwing temper tantrum
  • isolation = separation of idea and its accompanying emotions (e.g. w/very stressful/strong emotional situations)
    • veteran describing war atrocities in frank, non-emotional terms
  • undoing = symbolically nullifying an unacceptable or guilt-provoking though, idea or feeling by confession or atonement

4

Pathophysiology of hemochromatosis

  • Hemochromatosis gene (HFE) on chromosome 6 mutation ==> increased iron absorption @ GI tract
    • most common mutation = cyst => tyr missense mutation @ aa 282
  • one of most common inherited diseases; caucasians/N. european descent
  • ==> elevated ferritin and liver cirrhosis

5

Proteins that can be detected via Southwestern blot

  • proteins that bind DNA: trxn factors, nucleases, histones
  • trxn factors
    • c-Jun
    • c-Fos

6

Ras =

  • proto-oncogene
  • codes for membrane-bound G-protein
  • Ras ==> MAP kinase pathway ==> increased trxn

7

S-100 = 

  • homodimeric calcium-binding proteins
  • important in protein phosphorylation and cell growth/differentiation
  • marker for cells of neural crest derivation
    • melanocytes
    • schwann cells
  • marker for Langerhan;s cells and other dendritic cells

8

Increased VMA excretion + adrenal mass ==> dx?

  • pheochromocytoma
  • arise @ adrenal medulla ==> paroxysmal secretion of catecholamines
  • ==> intermittent H/A, palpitations, diaphoresis, HTN

9

Characteristics of MEN syndromes

  • MEN = multiple endocrine neoplasms
  • MEN 1 (AD) = tumors of parathyroid, pancreas, and pituitary
  • MEN 2A (AR) = medullary carcinoma of thyroid, pheochromocytoma, parathyroid tumor
  • MEN 2B (AR) = medullary carcinoma of thyroid, pheochromocytoma, mucosal neuromas
  • MEN 2A/2B <== RET (proto-oncogene) mutation
    • ==> MEN b/c organs are all derived from neural crest cells
    • NCS ==> 4 pharyngeal pouches + adrenal medulla
      • ph pouch 4 ==> parafollicular cells of thyroid ==> med. carcinoma of thyroid
      • NSCs ==> mesothelium of adrenal (adrenal medulla) ==> pheo

10

Thyroid cancers (basic)

  • parafollicular thyroid cells ==> medullary carcinoma of thyroid
  • follicular thyroid cells ==>
    • papillary thyroid cancer
    • follicular thyroid cancer

11

muscle/nerve important in eye adduction

  • medial rectus m.
  • CN III

12

CN III course in brain

  • oculmotor nucleus of midbrain
  • emerges anterior to midbrain ==> orbit via superior orbital fissure

13

Nerves that mediate corneal reflex 

  • sensory = nasociliary branch of first division of trigeminal n. (CN V1)
    • enters orbit @ superior orbital fissure
  • motor = temporal branch of facial n. (CN VII)

14

Structures entering orbit via superior orbital fissure

  • oculomotor nerve (CN III)
  • nasociliary branch of CN V1
  • trochlear nerve (CN IV)
  • abducens nerve (CN VI)
  • superior opthalmic vein

15

Two major types of immunization + mechanism of protection

  1. immunize w/bacterial antigen (e.g. capsule-like proteins of S. pneumo)
    1. ==> circulating antibodies that activate complement and induce phagocytosis of bacteria
  2. immunize w/toxoid (e.g. tetanus, diptheria)
    1. ==> circulating antibodies that neutralize bacterial products
    2. these antibodies do not destroy the bacteria itself as the disease is caused by toxins, not by circulating organisms

16

Diuretic overuse impact on blood pH/gases

  • diuretic overuse ==> compensatory increase in aldosterone
  • aldosterone ==> sodium + H2O retention + K+ and H+ loss @ kidneys ==> metabolic alkalosis
    • "contraction alkalosis"
  • labs = high pH, high HCO3, high pCO2

17

[MicroBio] Characteristics of Pseudomonas aeruginosa

  • oxidase-positive, non-lactose fermenting, gram (-)
  • ==> opportunistic pneumonia @ CF patients
  • ==> UTIs in patients w/indwelling catheters

18

[MicroBio] Characteristics of E. Coli

  • lactose-fermenting
  • gram (-) rode
  • ==> complicated and uncomplicated UTIs

19

[MicroBio] Characteristics of K. pneumoniae

  • lactose-fermenting
  • gram (-) rod
  • ==> spontaneous bacterial peritonitis, nosocomial pneumonia, UTIs

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