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Flashcards in Misc. UWorld Stuff Deck (27):
1

Tx of drug-induced Parkinsonism?

Drug class + 2 examples

Anticholinergics

benztropine and trihexyphenidyl

2

How can left atrial pressure be measured?

Pulmonary artery occlusion pressure (PAOP)

AKA pulmonary capillary wedge pressure

  • PA catheter (Swan-Ganz) used to dx pulm htn + in critical care
  • Catheter placed in pulmonary artery, inflated, and P backs up to catheter tip from LA + is measured

3

What may be cause of disseminated mycobacterial infection in childhood?

Why?

How can these kids be tx?

Interferon Signaling Deficiency

  • i.e. AR deficiency of IFN-y receptor
  • infected macrophages produce IL-12 > stimulate T/NK production of IFN-y > stimulates macrophage IC killing of mycobacteria (via JAK1/2 > STAT1)
  • tx with life-long anti-mycobacterials

4

Generally, what are serum Ca and PTH levels like in primary osteoporosis patients?

Normal


(wrongly answered low Ca and high PTH)

5

What is the mnemonic for structures arising from neural crest cells?

MOTEL PASS:

  • Melanocytes
  • Odontoblasts
  • Tracheal cartilage
  • Enterochromaffin cells
  • Laryngeal cartilage
  • Parafollicular cells (thyroid)
  • Adrenal medulla + all ganglia
  • Schwann cells
  • Spiral membrane

6

Mutation in primary myelofibrosis

JAK2

same as in PV, and ET

(treatable with ruxolitinib, a JAK2 inhibitor)

7

Mutations in...

acute promyelocytic leukemia?

CLL?

Burkitt?

Mantle cell lymphoma?

  • APL - t(15;17) PML/RARalpha
  • CLL - increased BCL2 expression
  • Burkitt - t(8;14) involving c-myc via EBV
  • Mantle cell - t(11;14) cyclin D1 overexpression

8

what is cumulative incidence?

total number of new cases of a disease during a given period divided by number of people at risk during that period

9

Antidote for cyanide poisoning and its mechanism

Amyl Nitrate

  • cyanide binds Fe3+, inhibiting mitochondrial cytochrome c oxidase > red skin, tachypnea/-cardia, headache, lactic acidosis + decr. veno-arterial O2 gradient
  • amyl nitrate oxidizes Fe2+ in hemoglobin to form Fe3+ (methemoglobin) which binds + sequesters cyanide
  • hydroxycobalamin and Na Thiosulfate can also be used (make nontoxic metabolites w/ Cn- > urinary excretion)

10

What structure prevents normal ascent of a horseshoe kidney?

What are horseshoe kidney pts at increased risk of (5)?

inferior mesenteric artery

  1. uteropelvic junction obstruction
  2. recurrent infection
  3. urolithiasis
  4. Wilms tumor (kids)
  5. Renal cell cancer (adults)

11

Process of granuloma formation in TB (cell types etc.)

  1. Macrophages phagocytose bacilli
  2. Ms present Ags to T cells
  3. CD4+ cells further stim macrophages
  4. Macros may for Langhans giant cells (mult. nuclei in horseshoe formation)
  5. (Macros also stim fibroblasts which help produce granulomas)

12

Cryptococcus neoformans

morpho, epidem, infection, dx, tx

  • yeast w/ polysacch capsule; round/oval with narrow-based bud
  • bird poop; inhaled; AIDS pt CD4 < 100
  • meningoencephalitis (fever, HA, confusion)
  • India ink > bubbly budding yeast; latex agg of CSF for polysacch Ag; Sabouraud culture
  • ampho B / flucytosine induction; fluconazole maintenance

13

How much of filtered water is absorbed in the different parts of the nephron?

  • PCT - ~60% regardless of hydration status
  • DL henle - ~20% due to corticopapillary gradient
  • AL henle + early DCT - impermeable
  • cortical + medullary CD - up to ~20% based on ADH > aquaporin translocation

14

Changes in levels of what molecule are seen in narcolepsy?

where?

decreased hypocretin-1

  • neuropeptides hypocretin-1 and 2 (orexin 1/2) made in lateral hypothalamus; promote wakefulness and inhibit REM sleep
  • normally detectable in CSF, but not elsewhere

15

Condition in which tyrosine becomes an essential AA

biochemical consequences + symptoms of the condition?

Phenylketonuria

  • AR deficiency of Phe hydroxylase inhibits Phe > Tyr conversion
  • excess Phe inhibits Tyr hydroxylase > decr. melanin (fair skin)/ catecholamine production
  • intellectual disability by 6 mos; seizures, eczema, low pigmentation, "musty" odor

16

Perinatal Hep B infection

  • risk factors
  • clinical findings
  • prevention

  • maternal viral load + HBeAg level
  • immune tolerance (no sx / low-normal LFTs); high chronic risk; high viral load + HBeAg in baby
  • HBsAg vacc + Ig within 12 hrs birth; maternal anti-viral tx; other routine vacc; serology 3 months after 3rd HB vacc dose

17

a holosystolic murmur heard at the apex subsides after diuretic + vasodilator treatment

what was the cause of the murmur + why did the tx help?

  • functional mitral regurgitation due to transient hemodynamic changes (NOT anatomical issues such as deformed cusps, calcified annulus, ruptured papillary muscles, etc.)
  • diuretics > decreased preload and end-diastolic LV volume > less LV dilation > less mitral dysfunction
  • vasodilator > decreased afterload > decreased intraventricular systolic pressure > less mitral dysfunction

18

How is urinary pH buffered when large amounts of H+ ions must be excreted (as in DKA)?

Buffers such as NH3 and HPO42- in the tubules bind H+ ions to form NH4+ and H2PO4-

  • NH3 (ammonia) is most important as it can be greatly increased via Gln metabolism in acidosis

19

Sx of Lithium toxicity (acute vs. chronic)

Conditions / factors which increase Li toxicity

  • acute = GI > N/V/D
  • chronic = neuro > confusion, agitation, ataxia, tremor, fasciculations (twitch)
  • volume depletion (decr. GFR) and drugs (thiazides, NSAIDs, ACE-I, tetracyclines + metronidazole)
  • (thiazides via decr. DCT Na reabs > stim PCT Na/Li reabs.)

20

what are the 2 main components of "advance directives"?

  1. living will - specifies end-of-life wishes re intubation, CP resuscitation, enteral feeding, etc.
  2. healthcare proxy - specifies individual who will make HC decisions for pt if they are unable to

21

What are type I and type II error?

And the "power" of a study?

  • Type I error (alpha) - probability of seeing a difference when there is no real difference
  • Type II error (beta) - probability of not seeing a difference when in reality there is one
  • Power is the probability of a study seeing a difference when there is one, so P = 1 - beta

22

What are the 2 clinical tests for hypocalcemia with fancy guys' names?

  • Chvostek sign - tapping facial nerve (CN VII) elicits nose/lip twitching
  • Trousseau sign - bp cuff inflation > carpal spasm (flexion of wrist/thumb, extension of fingers)

23

sensory innervation of tongue

  • Anterior 2/3:
    • sensory: lingual nerve (CN V/3)
    • gustatory: chorda tympani (CN VII)
  • Posterior 1/3:
    • sensory + gustatory: glossophar. n. (CN IX)

24

What are the 3 sets of nephric systems that arise from the nephrogenic cord?

What do they become?

  1. Pronephros - completely regresses
  2. Mesonephros - Wolffian duct (vas def, epidid); regress > Gartner's duct in females
  3. Metanephros - induced by ureteric bud (>collecting system); becomes all of nephron from glom to DCT

25

What are the two functions of type II pneumocytes?

  • surfactant production
  • proliferation in response to injury (progenitors for type I pneumocytes)

26

what is number-needed-to-harm?

  • # ppl who must be treated before 1 additional adverse event occurs
  • calculated using the absolute risk increase:
    • NNH = 1 / ARI

27

What is absolute risk increase?

the difference in adverse event rate between two study groups

  • 60/100 people die in a tx grp (60%) and 69/120 in a ctrl grp (57.5%) so ARI is 2.5%