8/23/12 Flashcards
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.
ALS
AR disease that affects children 5-15 y.o. Causes difficulty walking, hypertrophic cardimyopathy, kyphoscoliosis, foot abnormalities, and DM. Briefly describe the mutation.
Friedrich’s ataxia - GAA repeats code for the pathological frataxin protein.
Tx and mech of Tx for ALS.
Riluzole - decreases glutamate release
Name 3 causes for cold agglutinins (2 infectious, 1 non-infectious). Name a commonly associated lab finding.
Mycoplasma pneumoniae, EBV, hematologic malignancy; may cause anemia
What is the amino acid formula for collagen?
(-Gly-X-Y-)*333
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.
TXA-2 inhibition; PGE2 and PGI2 inhibition increases acid secretion from parietal cells.
label:
Does the disease follow GAS pharyngitis or skin infection:
PSGN?
Rheumatic fever?
PSGN: both
Rheumatic fever: ONLY PHARYNGITIS!
Many children in a daycare facility come develop jaundice and abdominal pain. Likely etiology? Route of spread?
HAV; fecal-oral
What is the defect responsible for SCID? What cells are deficient?
IL-2 receptors on T-cells; both T- and B-cells are deficient.
Chronic granulomatous disease results from a deficiency of?
NADP oxidase
Where is most water reabsorbed in the nephron under all circumstances?
straight proximal tubule
What are the 3 stages of gastric acid secretion from the parietal cells?
cephalic, gastric, instinal
Describe the chain of events in the gastric phase of gastric acid secretion.
- the chemical stimulus of food in and distention of the stomach causes gastrin release from the G-cells of the stomach, duodenum, and pancreas
- gastrin binds to CCK-B receptors on enterochromaffin-like cells and causes Histamine release
- histamine causes gastric acid release
What substance released in the intestinal phase of gastrin secretion inhibits histamine release from enterochromaffin-like cells (ECLs)?
peptide YY
What substances inhibit gastrin secretion?
prostaglandins, substance YY, and somatostatin
Martin, why do your allergies worsen when you eat a big meal?
Food in the stomach (via chemical and mechanical influences) causes histamine release from ECL’s. This, in turn, causes gastrin release from parietal cells.
What are the 2 medications for thyrotoxicosis?
propyllthiouracil (PTU) and methimazole
What is the major adverse side effect of medical treatments for thyrotoxicosis?
agranulocytosis
Which thyrotoxicosis medication would you use during pregnancy?
PTU
What is the difference between the two thyrotoxicosis meds?
PTU inhibits peripheral conversion of T4 to T3 and is not teratogenic, unlike methimazole.
What is used to prophylax HIV+ pts against MAC? At what Th count do you begin prophylaxis?
azithromycin; <50 cells/mL
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?
Trimethoprim-Sulfamethoxazole (TMP-SMX); @ 200 Th cells/mL. (Toxoplasma doesn’t infect until Th cell count below 100.)
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?
A “red neuron”.
