8/19/12

Question 1

Hemolytic anemia + hypercoagulability + decreased blood counts =

Answer 1

Paroxysmal Nocturnal Hemoglobinuria

Question 2

What kind of enzymes require biotin?

Answer 2

carboxylase

Question 3

What is thought to be the etiology of narcolepsy?

Answer 3

lack of orexin (hypocretin), a stimulatory neurotransmitter involved in wakefulness (suppressing REM sleep).

Question 4

What is the first line treatment for narcolepsy? Second line?

Answer 4

modafinil (provigil); amphetamines

Question 5

What happens to the embryonic vitelline veins after birth?

Answer 5

They become the hepatic portal system.

Question 6

What happens to the embryonic umbilical vv. after birth?

Answer 6

They degenerate; become ligaments.

Question 7

What happens to the embryonic cardinal vv. after birth?

Answer 7

They become the systemic veins.

Question 7

Isoniazid is structurally similar to what vitamin?

Answer 7

B6

Question 8

HGPRT, deficient in Lesch-Nyhan Syndrome, is part of the _______ pathway.

Answer 8

purine salvage

Question 9

What is enoxaparin?

Answer 9

LMWH

Question 10

What does enoxaparin bind and inactivate?

Answer 10

Factor Xa

Question 11

What does unfractionated heparin bind and inactivate?

Answer 11

Factor Xa AND thrombin (by forming a ternary complex w/ it and anti-thrombin).

Question 12

What is fondaparinux?

Answer 12

a Factor Xa inhibitor

Question 13

Formula for number needed to treat?

Answer 13

1/ Absolute Risk Reduction (ARR)

Question 14

Formula for Absolute Risk Reduction (ARR)?

Answer 14

risk in placebo group - risk in tx group

Question 15

If 25/100 die of disease X w/ placebo and 1/60 die of disease X with drug Y, what is the number needed to treat w/ drug Y vs. placebo?

Answer 15

1/(25/100 - 1/60) = 4.3 ~ 5

Question 16

Which diuretic will cause Ca++ retention and may be useful in preventing osteoporosis?

Answer 16

thiazides!!!!!!

Question 17

Aside from osteoporosis prevention, what is another fortuitous side effect of increased Ca++ absorption in certain diuretics?

Answer 17

decreased renal stone formation

Question 18

What two muscles are present in the inner ear? What are each of their functions?

Answer 18

tensor tympani; stapedius. Both dampen loud sounds, the tensor tympani mainly chewing, and the stapedius mainly one’s own voice.

Question 19

Which cranial nerves innervates the 2 muscles of the inner ear? Which muscle does each inervate?

Answer 19

tensor tympani - V3

stapedius - facial

Question 20

Why might a person with Bell’s palsy experience hyperacusis?

Answer 20

Paralysis of CN VII –> stapedius m.

Question 21

What are the two anti-inflammatory cytokines?

Answer 21

IL-10 and TgF-β

Question 22

What susbstance regulates the closure of K+ channels in pancreatic β-cells?

Answer 22

ATP

Question 23

Briefly describe the mechanism by which increased blood glucose causes the release of insulin from the pancreatic beta cell.

Answer 23

Glucose enters beta cell thru GLUT-2 and undergoes glycolysis. ATP produced by this process binds to KATP regulatory subunit of K+ channel to close it and depolarize the cell. Insulin is then released.

Question 24

What is the mech and effect of the alpha toxin of C. perfringens?

Answer 24

Alpha toxin, aka phospholipase C or lecithinase, cleaves phospholipids causing hemolysis and tissue necrosis.

Question 25

What is released from the pancreas as a result of stimulation by secretin?

Answer 25

bicarb

Question 26

What does CCK cause to be released from the pancreas? What else does it cause the secretion of?

Answer 26

pancreatic enzymes and bile from the gallbladder

Question 27

What does perfringens, as in C. perfringens mean?

Answer 27

to break through, similar to perforate. The alpha toxin of C. perfringens cleaves phospholipids, allowing the bacteria to break through the cell membrane.