test #28 4.19 Flashcards Preview

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Flashcards in test #28 4.19 Deck (133)
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1
Q
examples of delayed-type hypersensitivity reactions
A
(1) contact dermatitis
(2) granulomatous inflammation
(3) tuberculin skin test
(4) candida extract skin reaction
2
Q
delayed-type HSR mediated by..
A
T-lymphocytes (not Ab or complement).

reaction takes 1-2 days, bc antigen taken up by dendritic cells, present to CD4+ cells on MHC II.

Th1 cells secrete IFN-gamma, recruit & stimulate macrophages --> monocytic infiltrate.

[also occurs when 'walling off' TV
3
Q
increased WBC post-corticosteroids
A
falsely elevated. due to demargination (release from vascular walls) of cells
4
Q
2 disorders of mast cells
A
urticaria pigmentosum. systemic mastocytosis
5
Q
what two factors drive angiogenesis
A
VEGF and FGF
-vascular ENDOTHELIAL growth factor
- fibroblast growth factor

VEGF: angiogenesis in variety of tissues: normal, chronically inflammed, healing, neoplastic. increases endothelial cell motility and proliferation --> new capillaries.

FGF-2: made by many cells. significantly involved in (1) promotion of endothelial cell proliferation, migration, and differentiation. also: impt in (2) embryogenesis (stimulating angioblast production)

[FGF: angiogenesis, embryonic develoment, hematopoiesis, wound repair]
6
Q
somatomedin C
A
IGF-1

synthesized by growth-hormone influenced hepatocytes. stimulate cell growth and multiplication.
7
Q
barrier to angiogenesis
A
laminin in basement membranes
8
Q
non-viral-dependent nucleotides analogues
A
cidofovir (activated by cellular kinase) & tenofovir
9
Q
rx for thymidine kinase-deficient (acyclovir-resistant) varicella?
A
fosacarnet: (PYROPHOSPHATE analog viral DNA polymerase inhibitor)

cidofovir: broad spectrum NUCLEOTIDE. analogue of cytidine monophosphate (activated by CELLULAR kinase)
10
Q
factitious disorder vs. malingering
A
both CONSCIOUSLY creates symptoms.

factitious: for 1' gain (sick role/medical attn)

malingering: for 2' gain (avoid work, compensation)
11
Q
munchausen syndrome
A
chronic factitious disorder
12
Q
conversion disorder
A
unconscious; somatic.

post-stressor.

sudden neurological symptoms (loss of sensory/motor) with NO physical evidence.
13
Q
somatic disorder vs. factitious & malingering
A
somatic disorder syndromes (i.e. conversion, hypochondriaisis, somatization) are UNCONSCIOUS

factitious & malingering: CONSCIOUS
14
Q
somatization disorder (vs. conversion disorder)
A
somatoform disorder, several symptoms

usu begins <30 y/o. impact social/occupation.

4 pain
2 GI
1 sexual
1 neuro

with no physical exam / imaging evidence

(differs from conversion, which has specific NEURO and POST-STRESSOR)
15
Q
hypochondriasis
A
somatoform disorder

preoccupation/fear of having serious illness despite medical evaluation & assurance.

often, mistinterpretation of normal bodily symptoms (gas = colon cancer). associated w/ Dr. shopping
16
Q
body dysmorphic disorder
A
think body is pathologically flawed, when in fact, it is not.
17
Q
chromosome 3p deletion
A
VHL
18
Q
von-Hippel Lindau
A
autosomal DOMINANT.

cerebellar hemangioblastomas, clear cell renal carcinoma, and pheochromocytoma.

RCC develops in 40% of patients.

tumor supressor
19
Q
cerebellar hemangioblastoma, clear cell renal carcinoma, pheochromocytoma
A
VHL (tumor supressor chr. 3)
20
Q
location of RB
A
chr. 13

(osteosarcoma and retinoblastoma)
21
Q
location of NF-1
A
chr. 17
22
Q
WT-1 location
A
chr. 11
23
Q
location of chemoreceptor trigger zone (area postrema)
A
dorsal surface of medulla, caudal end of fourth ventricle.
24
Q
adhesion molecules
A
integrin, cadherin, selectin, Ig superfamily members
25
Q
laminins bind to
A
collagen, fibronectin, laminin in ECM
26
Q
fibronectin
A
large glycoproteins produced by fibroblasts & some epithelial cells. binds to integrin, matrix collagen, glycosaminoglycans. mediations cell adhesion
27
Q
heparan sulfate
A
proteoglycan component of ECM.

associated w/ reticular fibers and basal laminae. helps w/ endothelial cell attachment to BM.

does not bind to cell surface integrins.
28
Q
hyaluronic acid
A
glucuronic-acid containing glycosaminoglycan in ECM.

contributes to water retention in ECM -> lubricant properties. viscous, gel-like consistency.
29
Q
elastic fibers
A
core of elastin protein surrounded by fibrillin
30
Q
keratan sulfate
A
galactose-containing glycosaminoglycan. role in maintaining type I collagen fibril organization in cornea.
31
Q
aromatase deficiency
A
present early:
- mom virilization (androgens)

female:
- ambiguous/male genitalia
- primary amenorrhea & tall (no estrogen to fuse epiphyseal plate

male
- tall w/ osteoperosis
32
Q
aromatase rxns (2)
A
androstenedione -> estrone
testosterone -> estrogen
33
Q
aromatase deficiency vs. 21-b hydroxylase deficiency in girls
A
aromatase deficiency
- has mom virilization
- no hypotension w/ salt wasting & hyperkalemia
34
Q
auscultation site determined by..
A
position closest to where sound waves reverberate. NOT at position of valve
35
Q
glomerular splitting of basement membrane (2)
A
MPGN II and Alport syndrome
36
Q
Alport syndrome
A
triad:
1. glomerulonephritis
2. sensorineural deafness
3. eye problems

mutation in alpha-side chain of collagen type IV.

thinning and splitting of basement membrane

X-linked dominant.
37
Q
nasal mucosal ulcerations "saddle nose" w/ glomerulonephritis
A
granulomatosis w/ polyangiitis (wegner's)
38
Q
HSP 4 signs
A
IgA / C3 deposits everywhere
1. palpable purpura
2. abdominal pain
3. arthralgia
usu self-limiting, but can get..
4. glomerulonephritis & end-stage renal failure

usu post-infectious
39
Q
drugs w/ negative chronotropic effects
A
(1) b-blockers
(2) non-DHP calcium blockers
(3) digoxin (independent vagal effects)
(4) amiodarone
(5) sotalol (class III w/ b-blocking effects)
(6) cholinergic agonists
40
Q
what cell type exerts master control over iron metabolism?
A
HEPCIDIN, made by liver parenchymal cells
41
Q
fate of Fe2+ in GI system
A
absorbed via DMT-1 channel in duodenum, bind to intracellular FERRITIN..
(1) stay in enterocyte, and pass in stool when sloughed off
(2) exist basolaterally via FERROPORTIN -> bind to transferrin in blood -> taken up by cells via transferrin receptor

PATH determined by hepcidin!
42
Q
hepcidin
A
acute phase reactant. binds to ferroportin in enterocytes & macrophages & degrades it.

BLOCKS release of Fe2+. prevents iron overload.
43
Q
anemia of chronic disease
A
increased levels of hepcidin (from liver) down regulate ferroportin. trap Fe2+ in macrophages and enterocytes.
44
Q
filtered load =
A
GFR x Px
45
Q
excretion rate =
A
V x Ux
46
Q
RPF estimated w/
A
PAH clearance -- fully cleared
47
Q
GFR estimated w/
A
creatinine clearance (similar to inulin)
48
Q
normal filtration fraction
A
20% (GFR/RPF)
49
Q
when does glucose begin to appear in urine? when are glucose transporters maximally saturated?
A
- begin at 200mg/dL
- saturated at 375mg/dl
50
Q
normal GFR
A
100ml/min
180L/day
51
Q
when GFR is normal (100ml/min), large decreases in GFR, causes ___ in serum creatinine
A
small increases in serum creatinine
52
Q
when GFR is very low (<60ml/min), small changes in GFR causes ___ in serum creatinine
A
LARGE increases in serum creatinine
53
Q
serum creatinine can be normal after loss of how much GFR
A
even after 50% loss!
54
Q
general rule of thumb with changes in GFR & serum creatinine
A
everytime GFR halves, serum creatinine doubles.
55
Q
increase in cardiac output during exercise
A
5 L/min to 20 L/min
56
Q
early in exercise, how is CO maintained?
A
increase BOTH HR and SV
57
Q
late in exercise, how is CO maintained
A
increase only HR

(stroke volume maxes out)
58
Q
pulse pressure is directly related to? inversely related to
A
PP = systolic - diastolic
directly related to CO
inversely related to arterial compliance
59
Q
three sympathetic hemodynamic effects in exercise.

why does MAP only increase 2-40mmHg?
A
(1) increased CO
(2) venoconstriction to increase preload
(3) vasoconstriction to muscles not participating in exercise

only modest increase in MAP bc of MAJOR decrease in SVR due to...

local vasodilation in skeletal muscle (via adenosine, adenosine, K+, ATP, CO2, lactate)

in exercise, skeletal muscle can get 85% of CO
60
Q
infection of liver capsule w/ violin string adhesions of peritoneum to liver.
A
Fitz-Hugh-Curtis syndrome, resulting from PID
61
Q
manifestation of pelvic inflammatory disease
A
endometritis, salpingitis, tubo-ovarian abscesses, pelvic peritonitis

can result in infertility
62
Q
how does pregnancy increase risk of gallstones?
A
ESTROGEN: increase HMG-CoA reductase activity, bile = SUPERSATURATED w/ cholesterol

PROGESTERONE: reduce bile acid secretion, slow gall bladder emptying = HYPOMOTILE

together: ppt cholesterol crystals
63
Q
staphylococcus bacteremia associated with..
A
intravascular devices

(i.e. indwelling central venous catheters)
64
Q
in dehydration, fluid is primary reabsorbed by..
A
always PCT (~65% reabsorption), even in dehydration

(collecting ducts can take ~20% free water)
65
Q
Fenoldopam
A
SELECTIVE D1 agonist.
vasodilate most ARTERIAL beds (esp coronary, renal, splanchnic, peripheral)

overall decreased SVR.

increased flow to kidney allows for Na+ and H20 excretion

ONLY drug to reduce BP while increasing blood flow to KIDNEY
66
Q
rx for HTN emergency w/ concomittant renal insufficiency
A
fenoldopam
67
Q
diazoxide
A
anti-HTN

K+ activator, relax smooth muscle --> ARTERIAL vasodilation
68
Q
mechanism of hydralazine. must be given w/?
A
increase cGMP -> smooth muscle relaxation

arterioles > vein. afterload reduction

must give w/ beta-blocker, as it causes reflex increased contractility, HR, & fluid retention
69
Q
first-line rx for HTN in pregnancy?
A
hydralazine (increase cGMP) with methyl-dopa (a2 agonist)
70
Q
methyl-dopa
A
HTN in pregnancy. alpha-2 agonist
71
Q
use of hydralazine & diazoxide
A
though arteriole vasodilator, often cause significant increase in HR and contractility & Na+ and fluid retention
72
Q
nimodipine
A
DHP calcium channel blocker, used for post-subarachnoid hemorrhage (to prevent vasospasm)
73
Q
nicardipine
A
DHP calcium channel blocker. vasodilates arterioles & myocardium.

can cause tachycardia
74
Q
ways to get EHEC 0157:H7
A
- eating undercooked contaminted ground beef.
- person-to-person
- raw unpasterized milk
- swimming in / drinking sewage contaminated water
75
Q
1st line disease modifying for rheumatoid arthritis?
A
methotrexate.
76
Q
Leflunomide and TNF-alpha inhibitors for rheumatoid arthritis
A
also disease modifying agents, can use in combo w/ methotrextate

leuflunomide -- decreases pyrimidine synthesis
77
Q
methotrexate side effects
A
stomatitis (painful mouth ulcers) and hepatotoxicity (hepatitis, cirrhosis)
78
Q
hydroxychloroquine
A
unclear mechanism. accumulates in cell, and increases pH, reducing fxn.

antimalarial and used in SLE
79
Q
impt side effect of hydroxychloroquine
A
RETINAL DAMAGE
80
Q
formula for volume of distribution
A
amount of drug given (mg) / plasma concentration of drug (mg/L)
81
Q
what causes a drug to stay in blood (low volume of distribution) (3)
A
large molecular weight
bound extensively to plasma proteins
highly charged
(~3-5L)
82
Q
if drug has small molecular weight, but hydrophillic
A
will also distribute to interstitial space (~15L)
83
Q
if drug has small molecular weight, and uncharged
A
can also cross cell membranes -- ~41 volume of distribution
84
Q
Vd for drugs that are avidly bound in tissues?
A
higher than total body water (>40L)
85
Q
G. lambia in stool
A
O&P (smear w/ iodine stain)

ellipsoidal cysts w/ smooth defined walls and 2+ nuclei
86
Q
loperamide
A
opiate antimotility drug, can be used in traveller's diarrhea w/ no fever / blood in stool
87
Q
rx for inflammatory traveler's diarrhea (stool w/ mucus & blood)
A
ciprofloxacin
88
Q
rx for ancylostoma, ascaris, enterobius?
A
mebendazole
89
Q
rx for tapeworms (cestode) echinococcus granulosa
A
albenzadole
90
Q
mechanism of enfuvirtide
A
binds to gp41, blocks conformational change needed for fusion
91
Q
side effects of nnrtis (nevirapine, efavirenz, delavirdine)
A
hepatic failure (first 6 wks). also steven-johnsons
92
Q
propionyl-CoA made from catabolism of...
A
VOMIT
valine, odd-chain fatty acids, methionine, threonine, isoleucine, threonine
93
Q
propionyl-CoA carboxylase deficiency
A
build up proprionyl-CoA

poor feeding, vomiting, hypotonia, lethargy, dehydration

exacerbated by VOMIT:
valine, odd chain fatty acids, methionine, isoleucine, threonine & cholesterol
94
Q
L-asparaginase therapy
A
antineoplastic, gets rid of asparagine in serum (so rapidly dividing leukemic cells can't use it, as their synthesis of asparagine is impaired)
95
Q
histidine metabolism
A
deaminated to urocanic acid, converted to N-forminino-glutamate (FIGlu). forimino group donated to THF to form glutamate and forminino-THF.

oxidative decarboxylation of histidine forms histamine --> released by mast cells in type I HSR
96
Q
proline is a nonessential amino acid oxidized into..
A
glutamate
97
Q
prognosis of minimal change disease
A
rapid response to corticosteroids
98
Q
rx for all symptoms organophosphate poisioning?
A
pralidoxime (restore AchE)

atropine only stops muscarcinic effects, not nicotinic.
99
Q
bronchi differences in chronic bronchitis due to smoking vs. asthma?
A
both have: thickening of bronchial epithelium, basement membrane, and bronchial walls, as well as edema, inflammatory infiltrates, submucosal mucous gland enlargement, and bronchial smooth muscle hypertrophy

smoking: patchy squamous metaplasia & neutrophil infiltrate

asthma: eosinophil / mast cell infiltrate
100
Q
rupture of chordae tendineae can occur with..
A
endocarditis or MI
101
Q
diseases that cause myocardial fibrosis
A
dermatomyositis, muscular dystrophy, carcoidosis, scleroderma
102
Q
vegetations associated w/ bacterial endocarditis represent..
A
FIBRIN & PLATELET deposition at site of bacterial colonization.

often at site of endothelial damage
103
Q
myxomatous degeneration of valve
A
often mitral valve in MVP.
in the setting of CT diseases, like Marfan's.

can predispose to endocarditis.
104
Q
coarctation of aorta in infants pre-ductal pr post-ductal? cyanotic?
A
preductal. though there is right-to-left shunting, not enough to cause cyanosis.
105
Q
5T's of congenital cyanotic diseases
A
(1) tetrology of fallot
(2) tricuspid atresia
(3) total anomalous pulmonary return
(4) truncus arteriosus
(5) transposition of the great vessels
106
Q
what is tricuspid atresia?
A
congenital cyanotic heart disease.

one ventricle feeds both aorta & pulonary artery
107
Q
pulmonary alveolar proteinosis (PAP) (presentation & histology)
A
presents: gradually worsening of dyspnea and productive cough

histology: bilateral patchy pulmonary opacification due to intraalveolar accumulation of protein & phospholipid (constituents of surfactant)
108
Q
characterestic presentation of idiopathic pulmonary fibrosis
A
insidious-onset progressive exertional dyspnea, pulmonary function tests w/ restrictive profile

surgical biopsy: extensive interstitial fibrosis, paraseptal and subpleural cystic airspace enlargement (honeycomb lung)
109
Q
restrictive pulmonary function test
A
FVC low
FEV1/FVC normal (>80%)
110
Q
routes of hepatic abscess in US? in developing nations
A
1. portal vein
2. arterial supply
3. ascending biliary tract infection
4. direct invasion from adjacent source
5. penetrating injury

developing nations: parasitic infxn
111
Q
most likely cause of hepatic abscess in US
A
hematogenous spread of staph aureus
112
Q
valve abnormality in turner's
A
bicuspid
113
Q
nonstenotic bicuspid aortic valve murmur
A
aortic ejection sound. early systolic, high frequency click over cardiac apex and/or right second interspace
114
Q
most common cardiac abnormality in Turner's?
A
bicuspid aortic valve. can also have coarctation
115
Q
calcitonin
A
decreases serum Ca2+ levels.

decreases bone resorption of Ca2+ by osteoclast inhibition, but not a dominant hormone

levels increase when given exogenous Ca2+
116
Q
PTH regulates Ca2+ by.. (3)
A
(1) release from bone
(2) increased vitamin D to reabsorb more in gut
(3) increased renal absorption
117
Q
vitamin D under control of..
A
high PTH mainly.

also low Ca2+ and low PO4-
118
Q
when are calcitonin levels LOW?
A
when serum Ca2+ is low
119
Q
xeroderma pigmentosum has mutation in what type of enzyme
A
UV-specific ENDOnuclease

(not EXOnuclease)
120
Q
NADPH is required for..
A
fatty acid, cholesterol, and steroid synthesis
121
Q
parinaud syndrome
A
paralysis of conjugate vertical gaze due to lesion in superior colliculi (i.e. pinealoma)

(pineal gland is anterior-superior to superior colliculi)
122
Q
erythematous, papulovesicular, weeping, encrusted lesions that may evolve into thickened scaly plaques
A
eczematous dermatitis.

prone to bacterial superinfection -- yellow crust

5 types:
1. allergic contact dermatitis
2. atopic dermatitis
3. drug-related eczematous dermatitis
4. photo-eczematous dermatitis
5. primary irritant dermatitis
123
Q
spongiosus
A
seen in exzematous dermatitis (i.e. contact dermatitis)

epidermal accumulation of edematous fluid in intercellular spaces.

intercellular bridges become distinctive. epidermis = spongy.

edema can become so marked --> intraepidermal vesicles by tearing desmosomes apart
124
Q
acanthosis
A
increase in thickness of stratum SPINOSUM.

associated w/ psoriasis
125
Q
dyskeratosis
A
abnormal, premature keratinization of individual keratinocytes. strongly eosinophilic and may have small basophilic nuclear remnant.

found in squamous cell carcinoma
126
Q
hyperparakeratosis
A
retention of nuclei in stratum corneum (suggests incomplete keratinization)

normal on mucus membrane, but abnormal (actinic keratosis) in other areas
127
Q
hypergranulosis
A
excessive granulation in stratum granulosum of epidermis. seen in lichen planus
128
Q
lesser omentum
A
composed of hepatogastric and hepatodudenal ligament (along lesser curvature --> liver)
129
Q
greater omentum
A
along grater curvature
130
Q
adjustable gastric banding must pass through
A
lesser omentum, to enclose cardia
131
Q
falciform ligament of liver
A
attaches liver to anterior body wall (contains ligamentum teres)
132
Q
what ligament must be divided to have access to posterior stomach and anterior pancreas
A
gastrocolic ligament (connects greater curvature of stomach to transverse colon)

part of the greater omentum
133
Q
what is contained in splenorenal ligament (2)
A
(2) splenic artery & vein
(3) tail of pancreas