test #25 4.13 Flashcards Preview

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Flashcards in test #25 4.13 Deck (86)
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1
Q
skin rash, photosensitivity, arthralgia, renal disease in young women. general pathogenesis of disease
A
SLE. generally: autoantibodies bind autoantigens, immune complex deposition in vessel walls --> complement activation --> tissue inflammation and injury.

acute: fibrinoid necrosis
chronic: fibrosis & narrow lumen
2
Q
anti-Smith (anti-snRNPs) and anti-dsDNA
A
highly specific for SLE, but absence does not rule out!

60% have anti-dsDNA, 20-30% have anti-snRNP/smith. virtually all have anti-ANA, but not specific for lupus
3
Q
transposition of the great vessels
A
failure of aorticopulmonary septum to spiral normally during fetal development. aorta to right ventricle. pulmonary artery to left ventricle.

incompatible w/ life unless PDA, septal defect, or patent foramen ovale to allow for mixing.
4
Q
failure of proliferation
A
unilateral aplasia of fibula
5
Q
failure of oblieration
A
branchial cleft cyst
6
Q
failure of apoptosis
A
autoimmune disease due to persistence of autoreactive T/B cells
7
Q
failure of migration
A
hirschsprung, Kallman's
8
Q
failure of fusion
A
hypospadius
9
Q
where can the saphenous vein be harvested?
A
just inferolateral to the pubic tubercle
10
Q
when left anterior descending is occluded by plaque, which vein is often harvested?
A
left internal mammary artery (left internal thoracic artery).
11
Q
when multiple coronary arteries are needed, which veins are used?
A
saphenous vein grafts. longest in body, located superficially. courses up from medial foot --> medial malleolus --> up medial aspect of leg and thigh. joins femoral vein in proximal anterior thigh 3-4cm infeolateral to pubic tubercle. in femoral triangle (inguinal ligament, sartorius, adductus longus)
12
Q
most common type of hair less in males and females? genetics?
A
androgenetic alopecia (male pattern baldness). POLYGENIC inheritance w/ variable penetrance.

relationship between type of androgen receptor gene on X chromosome (X-linked recessive component)

NOT autosomal dominant as once thought
13
Q
common polygenic medial conditions
A
androgenetic alopecia, epilepsy, ischemic heart disease, schizophrenia, glaucoma, hypertension, malignancy, DM type II
14
Q
persistent vegetative state
A
severe brain damage that results in wakefulness without awareness. 50% of cases will regain consciousness in 6 months, but with severe subsequent disability
15
Q
acute salicylate intoxication
A
2 different acid base abnormalities simultaneously.

(1) respiratory alkalosis: SOON AFTER INGESTION. directly stimulate medullary respiratory center --> hyperventillation, increased loss of CO2.

(2) few hours later, anion gap metabolic acidosis, due to accumulation of organic acids in blood. (high doses, salicylates increase lipolysis, uncouple oxidative phosphorylation, inhibit TCA --> accumulate ketoacid, alctate, pyruvate.
16
Q
winter's formula
A
PaCO2 = (1.5 x HCO3- + 8) +/- 2
used to see if respiratory compensation for metabolic acidosis is appropriate or not.

(i.e. respiratory compensation or independent respiratory alkalosis)
17
Q
adverse effect in drugs w/ selective vasodilation of arterioles (hydralazine and minoxidil)
A
reduced arterial pressure, stimulates baroreceptor-mediated activation of sympathetics --> increased heart rate, contractility, increased RENIN --> Na+ and fluid retention

when given, add diuretics and sympatholytics
18
Q
persistent cough and angioedema with a anti-HTN drug?
A
ACE inhibitors
19
Q
angioedema
A
rapid swelling of dermis, subcutaneous tissue, mucosa, and submucosa
20
Q
how can c. botulinum be prevented?
A
thoroughly heating food prior to consumption (toxin is heat labile)
21
Q
classic paralysis in c. botulinum
A
descending paralysis, first manifesting w/ cranial n. involvement (diplopia, dysphagia, difficulty speaking).

note, both nicotinic and muscarinics aren't getting Ach
22
Q
hemicholinium
A
blocks choline entry into neuron
23
Q
bromoacetylcholine
A
inhibits chAt (choline acetyltransferase) blocking synthesis of acetate + choline --> ACh
24
Q
vesamicol
A
noncompetitively blocks vesicular Ach transporter.
25
Q
transference
A
unconscious shifting of emotions or desires associated with one person to another. often arise from childhood parent child relationship
26
Q
single most preventable cause of death and disease in US
A
smoking!

most effective preventative intervention

increased risk for macrovascular (MI, stroke), microvascular (retinopathy, nephropathy), complications of diabetes.

risk of MI-associated mortality decreases immediately upon smoking cessation
27
Q
omeprazole
A
inhibit H+/K+ ATPase, decreasing concentration of HCl in stomach lumen

primary active transport
28
Q
lidocaine
A
block voltage gated Na+ channels in sensory neurons, purkinje fibers, and ventricular cells
29
Q
drug to reduce nicotine cravings while decreasing pleasurable effects of cigarettes?
A
varenicline PARTIAL AGONIST of a4b2 nAChR.

prevents nicotine binding & reduces symptoms of withdrawal by mildly stimulating receptor --> limited release of dopamine, less stimulation of reward parthways than nicotine would.

reduce cravings and rewarding effects of use
30
Q
reinforcing effects of nicotine mediated by..
A
stimulate alpha-4-beta-2 nAChR in CNS
31
Q
biopsy of skin lesion w/ celiac disease & appearance
A
dermatitis herpetiformis. groups of small vesicles (papulovesicular) on extensor surfaces.

biopsy: neutrophil & fibrin & IgA at tips of dermal papilla --> forming microabscesses.
32
Q
gluten-free items? gluten-containing
A
gluten free: oats & rice.

gluten-containing: wheat, rye & barely
33
Q
abetalipoproteinemia
A
inherited inability to form chylomicrons - absence of B48. presents in first year of life w/ malabsorption, failure to thrive, progressive ataxia, abnormal RBCs (acanthocytes)
34
Q
skin manifestations of crohn's disease & ulcerative colitis. what additional feature foes crohn's have?
A
1. erythema nodosoum (tender subcutaneous nodules) &

2. pyoderma gangrenosum (deep ulcers w/ violaceous borders).

3. apthous ulcers
35
Q
normal gut flora. how is c. diff growth normally prevented?
A
very few aerobes: pseudomonas.

10% facultative anaerobes: e. coli, klebsiella, streptococcus, lactobacillus, staphylococcus, bacillus.

most strict anaerobes: bifidobacterium fusobacterium, clostridium, eubacterium, peptococcus, peptostreptococcus

suppress overgrowth of c. diff & others by competing for nutrients & adhesion sites (normal intestinal biomass)
36
Q
oral thrush, interstitial pneumonia, and severe lymphopenia in first year of life suggests..
A
vertical transmission of HIV-1 from mom to baby
37
Q
risk of HIV vertical transmission with no prenatal antirtroviral therapy
A
13-39%
38
Q
most effective maternal prophylaxis to prevent vertical transmission of HIV-1? (who have not had antiretroviral treatment previously
A
ZIDOVUDINE (nucleoside analogue, retroviral reverse transcriptase inhibitor). reduces risk by 2/3rds.

intiiate at 14 wks & continued. IV during labor. oral 6 wks postpartum.
39
Q
enfurvirtide
A
fusion inhibitor, blocks conformation changes in gp41 subunit required for fusion.
40
Q
which vessels supply the trochanteric anastomosis that feed the femoral head and neck (4)? which is the major one? which is susceptible in femoral neck fracture
A
superior & inferior gluteal arteries. medial & lateral femoral circumflex arteries.

major: medial femoral circumflex. susceptible to damage w/ femoral neck fractures due to close association w/ posterior aspect of femoral neck.

lateral femoral circumflex: courses anterior to femoral neck.
41
Q
obturator artery significance
A
gives rise to an artery that supplies blood to region of femoral head proximal to epiphyseal growth plate. impt in kids, minimal significance in kids
42
Q
cataracts in galactosemia?
A
due to galactose --> galactitol (via aldose reductase) due to either galactokinase or galactose 1-phosphoate uridyl transferase deficiency
43
Q
beta-galactosidase deficiency
A
lysosomal enzymes responsible for breakdown of glycosoaminoglycans. results in accumulation of keratin sulfate in lysosomes.

short stature, normal intelligence, altantoaxial instability, valvular heart disease

enzyme also impt for breakdown of lactose
44
Q
collagen's simple repetitive amino acid sequency
A
-(Gly-X-Y)-333.

glycine > proline > lysine

GLYCINE every 3rd position (most abundant amino acid in collagen). smallest, fits into tight spaces when form triple helix

many X and Y are PROLINE (ring structure introduces bend in polypeptide chain).

other X and Y form hydrophobic & charged regions to enable crosslinking to other molecules. LYSINE
45
Q
how does NaHCO3 help TCA overdose
A
correct QRS prolongation, reverse hypotension, and treat ventricular dysrhythmia

all effects of TCA due to blocked fast Na+ channels
46
Q
HbsAg
A
noninfective envelope coat glycoprotein of Hep B. forms tubules and spheres w/ 22nm diameter
47
Q
HbcAg
A
nucleocapsid core protein of Hep B
48
Q
HbeAg
A
nucleocapsid core protein + precore protein (which mediates secretion)

marker of replication & transmissibility
49
Q
Hbx (transcriptional transactivator of viral genes from X region
A
necessary for Hep B replication. also downregulates regular hepatocyte replication, important for development of hepatocellular carcinoma
50
Q
what maintains CO in aortic regurg
A
increased left ventricular end diastolic volume
51
Q
bone marrow diagnosis for multiple myeloma
A
>30% plasma cells in bone marrow
52
Q
symptoms of multiple myeloma and demographic. pathogenesis?
A
usu older (70 y/o).
CRAB:
hypercalcemia, renal failure, anemia, bone pain / lytic lesions
increased susceptibility to infxn

neoplasm of plasma cells. secrete IL-1 (osteoclast activating) and IL-6. hypercalcemia.

M-spike on serum protein electrophoresis (usu IgG or IgA)

Bence jones protein casts (immunoglobulin light chain ppt)

rouleoux on smear

renal failure due to amyloidosis, hypercalcemia deposits, bence jones protein casts, plasma cell infiltration.
53
Q
diseases w/ m-spike on serum protein electrophoresis (3)
A
(1) multiple myeloma (2) waldenstrom's macroglobulinemia (3) MGUS (monoclonal gammopathy of undetermined significance)
54
Q
waldenstrom's macroglobulinemia
A
hyperviscosity symptoms, M spike, no lytic bone lesions

(MM lytic bone lesions)
55
Q
MGUS (monoclonal gammopathy of undetermined significance)
A
precursor to multiple myeloma. M spike w/ 30% plasma cells in bone marrow)
56
Q
factors important for insulin resistance? mechanism?
A
free fatty acids, glucocortiocids, glucagon, catecholamines.

downstream SERINE phosphorylation of (1) beta-subunit of insulin receptor and (2) of IRS-1

instead of TYROSINE phosphorylation
57
Q
rx for seizures (DTs) in alcohol withdrawal
A
benzodiazepine (diazepam / chlordiazepoxide)
58
Q
most important side effect of benzodiazepines
A
sedation!

avoid first generation anti-histamines (diphenhydramine, dimenhydrinate, chlorpheniramine, hydroxyzine, promethazine)

also avoid: alcohol, barbituates, neuroleptics
59
Q
diphenhydramine, chlorpheniramine, diphenhydrinate, hydroxyzine, promethazine
A
1st generation antihistamines
60
Q
PABA-containing sunscreen
A
most potent & widely-used UVB (290-320 nm) radiation absorbers.

do NOT absorb UVA (320-400) (absorbed by avobenzone [specifically] and zinc-oxide containing [broadly]
61
Q
which UV radiation is major cause of ultraviolet radiation burns, histologic skin damage, UVR-induced immunosuppression, skin photo-aging, and photocarcinogenesis
A
UVB

generates ROS that damages skin
62
Q
what type of sunscreen blocks UVAI and II only
A
avobenzone
63
Q
which sunscreens provide broad-spectrum UVB, UVAI, and UVAII block
A
zinc-oxide containing
64
Q
rx for multiple myeloma
A
bortezimib (proteosome inhibitor)

allows for accumulation of protein in plasma cells --> apoptosis
65
Q
cytoplasmic inclusions in oligodendrocytes
A
PML
66
Q
gower's sign & calf enlargement in a male between 3-6
A
Duchenne muscular dystrophy. X-linked recessive. frameshift mutation of dystrophin. links actin to ECM
67
Q
Charcot-Marie-Tooth disease (aka heriditary motor and sensory neuropathy)
A
mutation of genes responsible for synthesis of MYELIN (& other components of peripheral n.)

decreased nerve conduction.

presentation: weakness of foot dorsiflexion due to involvement of common peroneal n.
68
Q
hyperkalemic periodic paralysis
A
ion channel myopathy
69
Q
rx for congenital adrenal hyperplasia (i.e. 21B-hydroxylase deficiency)
A
low doses of corticosteroids, suppressing ACTH.
70
Q
most common locations for colon cancer?
A
rectosigmoid > ascending > descending
71
Q
right vs. left sided colon cancer
A
right: exophytic. presents as iron deficiency anemia, associated w/ HNPCC (microsite instability)

left: infiltrate wall, narrow lumen, obstruction. associated w/ APC
72
Q
role of prostacyclin PGI2(4)
A
made by vascular endothelium. inhibits platelet aggregation, vascular tone, bronchial tone, and uterine tone.

in balance w/ thromboxane A2 (enhances platelet aggregating and vasoconstricts)
73
Q
kulchitsky cells
A
gut ECL cells
74
Q
hageman factor
A
factor XII of clotting cascade.
75
Q
kalikrein
A
converts kininogen into bradykinin
76
Q
which two brain regions are first damaged during global cerebral ischemia
A
FIRST: HIPPOCAMPUS (pyramidal cells)

and thenCEREBELLUM (purkinje cells)
77
Q
microscopy differences between crohn's and ulcerative colitis
A
crohn's - noncaseating granulomas.

ulcerative colitis - crypt abscesses. no granuloma.
78
Q
ependymal epithelium in choroid plexus
A
simple ciliated columnar.
79
Q
describe choroid plexus capillaries
A
unlike elsewhere in CNS, capillaries are FENESTRATED. columnar epithelium (ependymal cells) have TIGHT junctions --> selective
80
Q
pseudotumor cerebri
A
classically overweight young females. communicating hydrocephalous. related to decreased CSF outflow at arachnoid villi
81
Q
inheritance of glucose-6-phosphate dehydrogenase decfiency
A
x-linked recessive (most common human enzyme deficiency).

oxidative step of pentose-phosphate pathway:

needed to convert glucose-6-phosphate ---> 6-phosphogluconate (generate NADPH).

NADPH then given to glutathione (via glutathione reductase)
82
Q
2 steps in pentose phosphate pathway (HMP shunt)
A
oxidative:
glucose-6-phosphate ---> ribulose-5-phosphate
(rate limiting enzyme: glucose-6-phosphate dehydrogenase, 6-phosphogluconate is first pdt)

makes NADPH for glutathione reduction

nonoxidative
ribulose-5-phosphate ---> ribose 5 phosphate
(via transketolase, requires THIAMINE B1 exclusively)
83
Q
drugs that trigger oxidative stress & hemolysis in RBCs (dark urine in glucose-6-phosphate dehydrogenase)
A
primaquine, anti-malarial, anti-TB, nitrofurantoin, dapsone, bactrim, sulonfamides. FAVA beans
84
Q
how is the H2O2 (made by partial reduction of O2) in RBCs cleaned up
A
with glutathione peroxidase (reduces H2O2 with reduced glutathione) to make water
85
Q
class I antiarrhythmics generally have affinity for which types of receptors?

what are their relative Na+ channel bindings? how does this related to their indications / contraindications?
A
inactivated & active Na+ channels (not those in resting). therefore, use dependent (not enough time to be in 'resting' state'

relative Na+ channel binding strength 1C > IA > IB.

IC (morzicline, flecainide, propafenone) binds so strongly, will have accumulating affects w/ each cardiac cycle (takes long to dissociate), esp in tachyarrhythmia. so much so that block of conduction velocity in myocytes can be greater than AV node block ---> leading to pro-arrhythmic effects. CONTRAindicated in ischemic / structural defective tissue, bc will bind too avidly

IB (lidocaine, mexelitine, phenytoin) has less 'use dependence' bc binds less avidly, and dissociates rapidly (minimal cumulative effect). but, in ischemic tissue, reduce potential difference increases time Na+ channels are inactivated, allows for IB binding. useful for treating ischemia-induced ventricular arrhythmia.
86
Q
HR determined by
A
rate of If (funny current) depolarization in pacemaker cells