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Flashcards in #6 3/14 Deck (122)
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1

fever (in Celsius)? hyperpyrexia temp and cause? temp that causes neurological sequelae? what temp is incompatible w/ life?

fever = >38.3 C. hyperpyrexia = >40; severe infection, malignant hyperthermia, neuroleptic malignant syndrome, heat stroke. neurological seq = > 42 (mental status change, convulsions, delirium, coma). incompatible w/ life = >43

2

pathogenesis of fever

exogenous pyrogens (i.e. LPS) stimulate synthesis of endogenous pyrogens (IL-1, IL-6, TNF). enter brain and stimulate release of arachodonic acid (phospholipase A2) and synthesis of PGE2 --> increases hypothalamic set-point

3

age at which aspirin can be used w/o fear of reyes?

>12 y/o

4

acetaminophen mechanism?

anti-pyretic of choice in kids, inhibit cyclooxygenase in CNS, reduce PGE2 synthesis. oral or rectally = equally effective

5

symptoms of hypoglycemia (2; early and late).

1. EARLY: adrenergic symptoms (sweating, tremor, palpitations, hunger, nervousness) from epinephrine and norepinephrine release.
2. LATE & LOWER LEVELS: behavioral changes, confusion, visual disturbances, stupor. seizures

6

why is there a sympathetic surge when hypoglycemic (3)?

1. stimulate lipolysis in peripheral tissue 2. stimulate gluconeogenesis in live 3. decrease peripheral glucose consumption

7

what drugs can make symptoms of hypoglycemia? (and therefore, be avoided in diabetics)

non-selective B-blockers (propanolol, timolol, nadolol). inhibit epinephrine and norepinephrine-mediated compensation to hypoglycemia.

specifically, B2 blockade inhibits hepatic gluconeogenesis and peripheral glycogenolysis and lipolysis

(use B1 blocker if needed)

8

golden yellow / brownish cytoplasmic granules (2)? distinguish using?

either lipfuscin or hemosiderin; prussian blue stain (detects intracellular iron) differentiates.
black = hemosiderin

9

prussian blue histochemical rxn

colourless potassium ferrocyanide converted by iron into blue-black ferric ferrocyanide

10

hemosiderin-containing alveolar marcophages indicate?

"siderophages" or "heart-failure cells", indicate episodes of pulmonary congestion and edema (increased pulmonary capillary hydrostatic pressure) associated w/ chronic left-sided heart failure occurred previously.

increased intravascular pressure --> extravasation of iron-containing proteins & erythrocytes, eaten by macrophages --> converted to hemosiderin

note: pressure must be elevated at capillary beds for this to happen, not proximal to capillaries

11

what can cause granulomas in the lung (7)

TB, fungal infxn, inhalation of foreign particles, beryllium lung disease, granulomatosis w/ polyangiitis (wegners), sarcoidosis, histiocytosis X

12

describe HIV pathophysiology once intracellular. describe how raltegravir is an effective antiretroviral.

2 RNA strands. reverse transcriptase synthesizes complementary DNA strand --> makes DS DNA, integrates into host chromosome. uses HOST RNA pol II to make mRNA and ultimately proteins.

w/o integration, can't use host RNA pol II to make mRNA

13

(2) HIV fusion inhibitors

1. enfuvirtide (fusion inhibitor, binds to gp41) 2. maraviroc ( CCR5 inhibitor)

14

HIV polypeptide cleavage inhibitors

protease inhibitors -navirs

15

cleaved portion of proinsulin polypeptide in golgi is...

packaged along w/ insulin in secretory granules & secreted in equimolar concentrations

16

first line treatment for enterobiasis (infxn w/ enterobius vermicularis)? rx: in pregnant women?

first-line: albendazole / mebendazole = first-line. pyrantel pamoate = preferred in pregnancy

17

diethylcarbamazine used for (2)

1. Loa loa (loiasis) 2. wuchereria bancrofti (lymphatic filariasis)

18

ivermectin used for (2)

1. strongyloides stercoralis 2. onchocerca volvulus

19

nifurtamox used for (1)

trypanosoma cruzi

20

praziquantel (3)

1. schistosoma, 2. clonorchis sinensis, 3. paragonimus westermania

21

likelihood of plaque rupture depends on either (1) plaque stability or (2) plaque size?

(1) stability: mechanical strength of the overlying fibrous cap. balance of collagen synthesis and degradation. degradation --> chronic inflammation: macrophage secretion of metalloproteinases.

22

enzyme deficiency in Ehlers-Danlos syndrome? characterized by?

procollagen peptidase, cleaves terminal regions of procollagen molecule exocytosed by fibroblasts or SMC, transforming procollagen into insoluble tropocollagen. aggregate to form collagen fibrils

Ehlers-Danlos: disorganized collagen bundles, stretchable skin, hypermobile joints, short-stature

23

rule of thumb: if calcium levels are high, phosphate levels are...

low! and vice versa

24

PTHrP on phosphorous levels

low! PTHrP inhibits phosphorous reabsorption from proximal renal tubule

25

why does pregnancy increase the risk of DVT (5)?

increased clotting factors, decreased fibrinolysis, reduced levels of protein S, decreased venous tone, pressure of gravid uterus on IVC (predispose to venous stasis)

26

classic presentation of DVT (4)

unilateral leg pain, swelling, warmth. characteristic: tenderness of calf muscle on dorsiflexion of foot (Homan' sign)

27

mainstay rx: for DVT in pregnancy?

heparin --> increased ATIII activity (coumadin is teratogenic!)

28

Conn's syndrome. name 2 common causes. clinical presentation

primary hyperaldosteronism, 65% are aldosterone secreting adrenal adenomas. 30-40% idiopathic hyperaldosteronism, inclu primary adrenal hyperplasia.

hyperaldosteronism -- HTN & hypokalemia & metabolic alkalosis

hypokalemia: muscle paresis
hypokalemic alkalosis: paresthesia

29

weight gain & easy bruising are symptoms of...

glucocorticoid excess (Cushing syndrome)

bruising: inhibited collagen and matrix glyocsaminoglycan synthesis (thin, weak skin)

30

excess hair growth & virilization can result from excess of..

androgens (adrenal cortex)