#6 3/14 Flashcards
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
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
age at which aspirin can be used w/o fear of reyes?
> 12 y/o
acetaminophen mechanism?
anti-pyretic of choice in kids, inhibit cyclooxygenase in CNS, reduce PGE2 synthesis. oral or rectally = equally effective
symptoms of hypoglycemia (2; early and late).
- EARLY: adrenergic symptoms (sweating, tremor, palpitations, hunger, nervousness) from epinephrine and norepinephrine release.
- LATE & LOWER LEVELS: behavioral changes, confusion, visual disturbances, stupor. seizures
why is there a sympathetic surge when hypoglycemic (3)?
- stimulate lipolysis in peripheral tissue 2. stimulate gluconeogenesis in live 3. decrease peripheral glucose consumption
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)
golden yellow / brownish cytoplasmic granules (2)? distinguish using?
either lipfuscin or hemosiderin; prussian blue stain (detects intracellular iron) differentiates.
black = hemosiderin
prussian blue histochemical rxn
colourless potassium ferrocyanide converted by iron into blue-black ferric ferrocyanide
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
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
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
(2) HIV fusion inhibitors
- enfuvirtide (fusion inhibitor, binds to gp41) 2. maraviroc ( CCR5 inhibitor)
HIV polypeptide cleavage inhibitors
protease inhibitors -navirs
cleaved portion of proinsulin polypeptide in golgi is…
packaged along w/ insulin in secretory granules & secreted in equimolar concentrations
first line treatment for enterobiasis (infxn w/ enterobius vermicularis)? rx: in pregnant women?
first-line: albendazole / mebendazole = first-line. pyrantel pamoate = preferred in pregnancy
diethylcarbamazine used for (2)
- Loa loa (loiasis) 2. wuchereria bancrofti (lymphatic filariasis)
ivermectin used for (2)
- strongyloides stercoralis 2. onchocerca volvulus
nifurtamox used for (1)
trypanosoma cruzi
praziquantel (3)
- schistosoma, 2. clonorchis sinensis, 3. paragonimus westermania
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.
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
rule of thumb: if calcium levels are high, phosphate levels are…
low! and vice versa
PTHrP on phosphorous levels
low! PTHrP inhibits phosphorous reabsorption from proximal renal tubule