8/23/12

Question 1

Affects middle-aged pts. Atrophy of both upper and lower motor neurons. Anterior horn neurons, precentral gyrus, and CN V, IX, X, and XII affected.

Answer 1

ALS

Question 2

AR disease that affects children 5-15 y.o. Causes difficulty walking, hypertrophic cardimyopathy, kyphoscoliosis, foot abnormalities, and DM. Briefly describe the mutation.

Answer 2

Friedrich’s ataxia - GAA repeats code for the pathological frataxin protein.

Question 3

Tx and mech of Tx for ALS.

Answer 3

Riluzole - decreases glutamate release

Question 4

Name 3 causes for cold agglutinins (2 infectious, 1 non-infectious). Name a commonly associated lab finding.

Answer 4

Mycoplasma pneumoniae, EBV, hematologic malignancy; may cause anemia

Question 5

What is the amino acid formula for collagen?

Answer 5

(-Gly-X-Y-)*333

Question 6

Two mechanisms by which aspirin increases risk of GI bleeding. First, one that occurs at low doses, and second one that only occurs at high doses.

Answer 6

TXA-2 inhibition; PGE2 and PGI2 inhibition increases acid secretion from parietal cells.

Question 7

label:

Answer 7

Question 7

Does the disease follow GAS pharyngitis or skin infection:

PSGN?

Rheumatic fever?

Answer 7

PSGN: both

Rheumatic fever: ONLY PHARYNGITIS!

Question 8

Many children in a daycare facility come develop jaundice and abdominal pain. Likely etiology? Route of spread?

Answer 8

HAV; fecal-oral

Question 9

What is the defect responsible for SCID? What cells are deficient?

Answer 9

IL-2 receptors on T-cells; both T- and B-cells are deficient.

Question 10

Chronic granulomatous disease results from a deficiency of?

Answer 10

NADP oxidase

Question 11

Where is most water reabsorbed in the nephron under all circumstances?

Answer 11

straight proximal tubule

Question 12

What are the 3 stages of gastric acid secretion from the parietal cells?

Answer 12

cephalic, gastric, instinal

Question 13

Describe the chain of events in the gastric phase of gastric acid secretion.

Answer 13

1. the chemical stimulus of food in and distention of the stomach causes gastrin release from the G-cells of the stomach, duodenum, and pancreas
2. gastrin binds to CCK-B receptors on enterochromaffin-like cells and causes Histamine release
3. histamine causes gastric acid release

Question 14

What substance released in the intestinal phase of gastrin secretion inhibits histamine release from enterochromaffin-like cells (ECLs)?

Answer 14

peptide YY

Question 15

What substances inhibit gastrin secretion?

Answer 15

prostaglandins, substance YY, and somatostatin

Question 16

Martin, why do your allergies worsen when you eat a big meal?

Answer 16

Food in the stomach (via chemical and mechanical influences) causes histamine release from ECL’s. This, in turn, causes gastrin release from parietal cells.

Question 17

What are the 2 medications for thyrotoxicosis?

Answer 17

propyllthiouracil (PTU) and methimazole

Question 18

What is the major adverse side effect of medical treatments for thyrotoxicosis?

Answer 18

agranulocytosis

Question 19

Which thyrotoxicosis medication would you use during pregnancy?

Answer 19

PTU

Question 20

What is the difference between the two thyrotoxicosis meds?

Answer 20

PTU inhibits peripheral conversion of T4 to T3 and is not teratogenic, unlike methimazole.

Question 21

What is used to prophylax HIV+ pts against MAC? At what Th count do you begin prophylaxis?

Answer 21

azithromycin; <50 cells/mL

Question 22

The same drug combo is used to prophylax HIV+ pts. against Pneumocystis jiroveci and Toxoplasma gondii. What is this drug combo and when do you begin administration?

Answer 22

Trimethoprim-Sulfamethoxazole (TMP-SMX); @ 200 Th cells/mL. (Toxoplasma doesn’t infect until Th cell count below 100.)

Question 23

A neuron following ireversible injury displays shrinkage of the cells body, increased eosinophilia, pyknosis of the nucleus, and loss of the Nissl substance. What do you call this neuron?

Answer 23

A “red neuron”.