test #17 4.5 Flashcards Preview

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Flashcards in test #17 4.5 Deck (159)
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1

what converts NE to E

PNMT, phenylethanolamine-N-methyltransferase

2

dopa stands for..

dihydroxyphenylalanine

3

how does cortisol affect epinephrine secretion?

adrenal venous drainage cortex inwards. cortisol produced in fasiculata will travel into adrenal medulla --> increase expression of gene encoding PNMT.

4

MAO converts..

epinephrine and NE to dihydroxymandelic acid

5

COMT converts..

epinephrine to metanephrine. norepinephrine to normetanephrine

6

Rh- women are treated with what 28 wks into gestation & immediately after? why?

treat with IgG against Rh (D) antigen. RhoGAM. stops mother from mounting immune response to Rh+ baby. small amounts, so IgG does not travel transplacentally & hurt baby.

7

RhoGAM is.. goal of therapy?

IgG against Rh (D) antigen. prevent mom from EVER mounting an immune response to Rh factor. Abs cover fetal erythrocytes & mom will sequester in spleen.

8

what type of immune response is mounted when Rh- mom exposed to Rh antigen in baby? what happens in subsequent pregnancy?

after transplacental fetomaternal hemorrhage, mom will mount maternal Ab response, form memory B-lymphocytes. subsequent prengnancies, Rh+ fetus at risk for hemolytic disease of newborn (erythroblastosis fetalis). maternal IgG anti-Rh antibodies cross placenta, enter fetal circulation, massive hemolysis of fetal erythrocytes.

9

IgG or IgM in RhoGAM? why?

IgG! while IgM is good for promoting agglutination of foreign cells, this isn't so useful bc of low concentration of fetal cells in maternal circulation. IgG does not cause significant transplacental fetal hemolysis bc so little given.

10

somatostatin decreases secretion of.. (5)

(1) secretin (2) CCK (3) glucagon (4) insulin (5) gastrin. insulin is inhibited far more than glucagon. net = hyperglycemia.

11

somatostatin inhibits secretion of both glucagon and insulin. which is inhibited more?

insulin inhibited more. net effect: HYPERGLYCEMIA

12

secretin

adjust secretions from stomach and pancreas (affects environment of duodenum). S cells in crypts of Lieberkuhn in duodenum. also helps regulate duodenal pH (increase bicarb secretion in duodenum and inhibit acid secretion from stomach)

13

somatostatin analogues..

octreotide and lanreotide

14

deltaF508 mutation causes... (2) problems in CFTR

(1) abnormal protein folding and (2) failure of glycosylation. = absent from exocrine ductal cells.

15

protein abnormality of Friedreich's ataxia? important for which 2 things. at what level is this gene affected.

frataxin gene: codes for mitochondrial protein, important for (1) respiratory fxn and (2) iron homeostasis. GAA repeat disruptions TRANSCRIPTION

16

inflixamab

monoclonal Ab that irreversibly binds to & inhibits TNF-alpha

17

what enzyme is exclusively expressed in inflammatory cells?

COX-2

18

allopurinol

xanthine oxidase inhibitor

19

APML is what type of AML?

M3 type

20

what suggests good prognosis in ALL (children)?

presence of CD10 antigen (CALLA)

21

causes of low glucose, high insulin, high c-peptide?

excess sulfonylurea & meglitinide use (stimulates insulin secretion). note: somatostatinoma inhibits insulin far more than glucagon.

22

sulfonylurea & meglitinide?

insulin secretagogues

23

differentiate factitious hypoglycemia (sulfonylurea/meglitinide use) from insulinoma

urine hypoglycemic agent screen

24

presentation of glucagonoma (3)

(1) hyperglycemia (2) anemia (3) necrolytic migratory erythema (raised erythematous rash affecting face, groin, and extremities.

25

pancreatic cholera, or VIPoma (non-beta cell pancreatic islet cell tumor) causes..

results in WDHA syndrome (watery diarrhea, hypokalemia, achlorhydria).

26

what epidemiological measure depends on prevalence?

positive predictive value INCREASES w/ increased prevalence. more common the disease, more likely a patient with a positive test will be a true positive. [NPV: inverse association w/ prevalence, as prevalence increases, NPV decreases

27

which epidemiological values are inherent to the test itself?

sensitivity and specificity.

28

reliability

provision of identical measurements on different occasions separated by short time interval (reproducible)

29

describe acid fast stain process:

1. aniline dye (CARBOLFUCHSIN) -- penetrate wall and bind MYCOLIC ACID 2. treat slide w/ hydrochloric acid & alcohol - will dissolve outer cell membranes of nontuberculous bacteria, but presence of mycolic acids prevents decoliarization

30

describe mycobacterial cell wall

encapsulated w/ mycolic acid -- waxy, long-chain fatty acid, covalently bound to the sugars within the cell wall