March 20 Test 1 Flashcards Preview

1 USMLE-rx > March 20 Test 1 > Flashcards

Flashcards in March 20 Test 1 Deck (18):
1

What is the MOA of Digoxin?

Inhibits Na/K ATPase---causes increased Ca--positive inotrophy
-decreased ESV

Also stimulates vagus nerve--reducing HR
-Allows for longer filling time

2

What is the MOA of Tacrolimus?

Inhibits Calcineurin--binds the FK506 binding protein--prevents IL-2 transcription

3

What is the MOA of Disulfiram?

Inhibits acetaldehyde dehydrogenase--causing accumulation of acetaldehyde--intermediate from ETOH to Acetate---this causes hangover symptoms

4

What are the 5 organisms that can cause reactive arthritis?

Shigella
Salmonella
Yersinia
Campylobacter
Chlamydia

5

What portion of the large bowel is most susceptible to ischemia due to being a watershed area?

Splenic flexure

6

What portion of the lymph node is least developed in the contexts of Di-george syndrome?

Paracortex--lymph node compartment that housed T-cells

7

Mutations of tumor suppressor gene WT1 and WT2 on Chromosome ____ occurs with Wilms tumor.

11

8

What is deficient in Tay-Sachs disease and what substrate accumulates?

Deficient--Hexosaminidase A
Accumulation--GM2 ganglioside

9

What is the molecular role of bcl-2 protein?

Antagonist of apoptotic cell death

Along with bcl-x they prevent the release of cytochrome C and stops binding of APAF-1 and activating of the caspase cascade

So when its up-regulated in follicular lymphoma then malignant transformation is promoted

10

Young pt presents with tendon xanthomas and major increase in serum LDL, and an uncle who died of MI at age 20. Dx?

Familial hypercholesterolemia IIa--Absent or defective LDL receptors

11

What hormonal changes are seen with menopause?

Decreased estrogen

Increased FSH, LH and GnRH
-No negative feedback of estrogen

Before age 40 with these labs--primary ovarian insufficiency

12

What endocrine hormones used cAMP signaling pathway?

FSH
LH
ACTH
TSH
CRH
hCG
ADH
MSH
PTH
calcitonin
GHRH
Glucagon

FLAT ChAMP

13

What estrogen is important during menopause and where is it produced?

Estrone--produced by adipocytes

14

What disease has Cafe-au-lait spots, Lisch nodules (pigmented iris hamartomas), cutaneous neurofibromas, optic gliomas and pheochromocytoma?

Neurofibromatosis type I--mutated NF1 tumor suppressor gene on ch. 17

15

What substrate is increased in the urine with lead poisoning?

d-aminolevulinic acid--only at very high lead levels

16

What do the fibrates activate in order to increase HDL?

Activated PPAR-a to induce HDL synthesis

17

Genetic male (46, XY) age 14 presents with recent masculinization of external genitalia, which was previously ambiguous. Testes are found to be present in the abdomen. Dx?

5a-reductase deficiency--testosterone cannot be turned into DHT which is responsible for formation of external gonads

Feminized genitalia with normal internal genitalia

18

What is inspiratory reserve volume?

The amount of air that can be inhaled after normal breath of air