test #30 4.20 Flashcards
1
Q
opsoclonus-myoclonus syndrome
A
non-rhythmic conjugate eye movement w/ myoclonus
2
Q
non-rhythmic conjugate eye movement w/ myoclonus?
A
opsoclonus-myoclonus
3
Q
most common extracranial childhood tumor
A
neuroblastoma, usu from adrenal medulla
4
Q
Wilm’s tumor vs. neuroblastoma
A
neuroblastoma: firm, irregular mass. cross midline.
wilm’s tumor: smooth and unilateral
5
Q
presentation of neuroblastoma?
A
child ~2y/o. retroperitoneal mass, HTN.
6
Q
neuroblastoma mets
A
invasion of epidural space: “dumbbell tumor” spinal cord compression
bone: pancytopenia
liver: hepatomegaly
skin: palpable nodules
periorbital: proptosis, periorbital ecchymoses
paraneoplasic: opsoclonus, myoclonus, truncal ataxia
7
Q
urine w/ neuroblastoma
A
increased HVA in urine
8
Q
genetics of neuroblastoma
A
n-myc amplification
9
Q
prognosis
A
better if <1 y/o
worse with higher n-myc amplification
10
Q
formation of annular pancreas
A
ventral pancreatic bud cleaves into two parts, fuse w/ dorsal bud on either side – can compress duodenal lumen
11
Q
heteroplasmy
A
mixture of two types of genetic material (i.e. inherit some normal & mutated mitochondria)
12
Q
mitochondria inheritance
A
ovum has many mtDNA. few copies in sperm are lost during fertilization.
variability bc during mitosis, mitochondria are RANDOMLY distributed between daughter cells
13
Q
characterestics of mitochondrial diseases
A
- affect both male & female w/ equal frequency
2. variable degrees of severity: due to heteroplasmy
14
Q
three mitochondrial diseases
A
- leber hereditary optic neuropathy
- myoclonic epilepsy w/ ragged red fibers MERRF
- mitochondrial encephalomyopathy w/ lactic acidosis and stroke-like episodes MELAS
15
Q
myoclonic seizures and myopathy associated w/ exercise. skeletal biopsy w/ irregularly shapped muscle fibers (ragged red)
A
myoclonic epilepsy w/ ragged red fibers.
mitochondrial disease
16
Q
leber hereditary optic neuropathy
A
mitochondrial disease.
bilateral vision loss
17
Q
seizure disorder, several stroke-like episodes, increase lactic acidosis.
affected siblings w/ variable degrees of severity
A
MELAS
mitochondrial encephalopmyopathy w/ lactic acidosis & stroke-like episodes (MELAS)
18
Q
variable expressivity vs. variable degrees of severity
A
variable expressivity: differences in severity of autosomal dominant disorders. i.e. Marfan w/ only tall stature, others w/ also root dilation.
NOT a feature of mitochondrial diseases (variable degree of SEVERITY)
19
Q
gram negative lactose non-fermenters?
A
oxidase positive: p. aeruginoas
oxidase negative: shigella, salmonella, proteus
20
Q
differentiate shigella vs. salmonella & proteus in culture
A
all non-lactose fermenters, oxidase negative.
salmonella & proteus: (1) H2S production (black on TSI agar) (2) mobile
shigella: (1) NO H2S production, not black (2) NOT mobile
21
Q
essential pathogenic mechanism for shigella
A
musocal invasion!
via M cells in peyer’s patches
induces apoptosis of host cell and spreads to adjacent ones via protrustions (via host cell-actin polymerization)
less important in pathogenesis: also releases shiga toxin. A subunit inactives 60s ribosome (halts protein synthesis).
does NOT colonize in intestine. only there during active infection.
does NOT cause bacteremia. survives within mucosal layer of intestine
22
Q
which enteric bacteria penetrate mucosa & proliferate in mesenteric nodes?
A
salmonella typhi and yersenia enterocolitica.
23
Q
which bacteria causes pseudoappendicitis?
A
yersenia enterocolitica. mesenteric lymph node infection, RLQ pain.
24
Q
work of breathing is a balance between..
A
against elastic resistance of lung and against airflow resistance
25
when is work done against elastic resistance HIGH?
high tidal volumes
26
when is work done against airway resistance HIGH
respiratory frequency
27
relationship of elastic resistance and air flow on work of breathing.
inverse relationship.
elastic recoil favors low tidal volume (high respiratory rate)
airflow resistance favors high tidal volume (low respiratory rate)
28
COPD / asthma (high airway resistance) minimize work of breathing by..
have increased airway resistance, so increase TV, minimize RR
29
pulmonary fibrosis / edema (stiff lungs: high elastic resistance) minmize work of breathing by
rapid shallow breaths (low TV, high RR)
30
fate of mRNA once it leaves cytoplasm (2)
(1) associate w/ ribosomes = translation
(2) associate w/ P body proteins: distinct foci in eukaryotic cytoplasm, involved w/ mRNA regulation & turnover. role in translation repression and mRNA decay, contains numerous proteins and RNA exonucleases, mRNA decapping enzymes, constituents involved in mRNA quality control and microRNA-induced mRNA silencing. also: mRNA storage (for later use)
31
polyadenylation sequence
3' end of RNA
| no need for templatte. recognition sequence AAUAAA
32
5' cap on mRNA?
7-methylguanosine. unique 5' to 5' linkage.
33
cytoplasmic P bodies
impt role in mRNA translation regulation, degradation and storage
34
likelihood ratio positive
sensitivty / 1-specificity
test w/ LR+ greater than 10 significantly increases likelihood that patient will have disease for which they are being tested
35
right brachiocephali is forned by union off..
right subclavian and right internal jugular.
| right external jugular drains into right subclavian
36
brachiocephalic obstruction vs. SVC obstruction?
right side only vs. both sides of face & arms
37
guyon's canal
between hook of hamate and pisiform bone. cause ulnar n. (dysesthesia on ulnar side of hand and weakness of intrinsic muscles of hand)
38
axillary n. innervates
deltoid and teres minor.
affected w/ fracture of surgical neck of humerus
39
brown pigment stones in gallbladder
(asian) usu arise secondary to infection of biliary tract, which results in release of B-GLUCORONIDASE by injured hepatocytes & bacteria. --> h
ydrolysis of bilirubin glucoronides and increased amount of UNCONJUGATED BILIRUBIN in bile.
recall unconjugated bilirubin = not water soluble!
40
7-alpha-hydroxlase
converts cholesterol into bile acids.
41
vassopressin. ADH receptor actions (2)
primary inhibitor of free water excretion
V1: vasoconstriction & prostaglandin release
V2: increase H20 permeability urea
42
how does vasopressin maximally concentrate urine
(1) express aquaporin receptors in collecting duct.
(2) increases number of passive urea transporters in inner medullary collecting duct (allows substantial number of highly concentrated urea to enter medullary interstitium)
when ADH = high, urea resorption contributes 50% of total osmolarity of medulla
43
which infections increase risk of brown pigment stones?
bacteria w/ beta-glucoronidase to unconjugate bilirubin in gallbladder OR damage heptocytes to release beta-glucoronidase.
biliary infection w/ (1) e. coli (2) ascaris lumbricoides (3) liver fluke Opisthorchis sinensis
44
how is copper normally excreted?
into BILE
| via hepatocyte copper transporting ATPase (ATP7B gene
45
wilson's disease: 2 pathogenesis
autosomal recessive, chr. 13.
(1) defect in Cu2+ excretion into bile (ATPase transporter in hepatocytes)
(2) failure of copper to enter circulation as ceruloplasmin
all leads to copper accumulation in liver, brain, cornea, kidney, and joints
46
manifestations of wilson's disease
Copper is Hella BAD
```
C:
decreased ceruloplasmin
cirrhosis
corneal deposits (kayser-flesicher rings)
copper accumulation
carcinoma (hepatocellular)
```
H:
hemolytic anemia
B:
basal ganglia degeneration (parkinsonian symptoms
A:
asterixis
D:
dementia, dyskinesia, dysarthria
47
kernicterus
billirubin-induced brain damage. often in (1) basal ganglia (2) auditory nucleus (3) oculomotor nucleus
48
where can urea be reabsorbed (3)
(1) PCT -- (reabsorbs about half of filtered load)
(2) thin ascending loop of henle
(3) medullary collecting duct -- ADH sensitive
49
differentiate atypical CD8+ lymphocytes in infectious mononucleosis vs. immature blasts?
atypical CD8+ lymphocytes: abundant blue cytoplasm, basophilic rim <3 RBCs.
immature blasts: less cytoplasm, no bizzarre nuclear changes
50
EBV increases risk of what 3 things
(1) Hodgkin's lymphoma
(2) non-hodgkin's -- Burtkitt
(3) nasopharyngeal carcinoma
51
which macrolide does not inhibit CP450?
azithromycin
52
which statin is not metabolized by p450 (so less at risk for drug intxn)
pravastatin
53
hepatitis B viral replication process
DNA hepadnavirus
partially DS
polymerase has DNA polymerase & RNA-reverse transcriptase dependent properties
1. partially DS DNA enters nucleus
2. viral polymerase finishes --> DS DNA (dna-dep-dna pol)
3. host RNA pol makes viral transcripts
4. viral polymerase reverse transcribes viral transcripts -- DNA (dna-dep rna pol)
54
viral class for hep A?
RNA picornavirus (naked icosahedral)
55
viral class for hep E?
RNA hepevirus (naked icosahedral)
56
viral class for hep C?
RNA flavivirus (enveloped icosahedral)
57
viral class for hep D?
delta virus
- SS circular
- uncertain capsid
- requires hep B coinfection
58
viral class for hep B?
DNA hepadnavirus
- enveloped icosahedral
- circular partial DS DNA
59
replicative sequence for retroviruses (HIV, HTLV)
one stranded + RNA -->
template DS DNA -->
progeny one stranded +RNA
60
replicative sequence for hepatitis B?
(partial) DS DNA -->
template +RNA -->
progeny DS DNA
has RNA intermediate!
61
replicative sequence for papovavirus, adenovirus, herpesvirus, poxvirus?
DS DNA -->
template DS DNA -->
progency DS DNA
62
affect of EBV infection on B cells
enter cell cycle & proliferate continuously (transformation / immortalization)
EBV encoded oncogenes activate & proliferate anti-apoptotic signaling pathways. can propagate indefinitely in vitro.
63
Tzanck test identifies
HSV or VZV
epithelial cells from ulcer, Wright-Giemsa stain. look for..
(1) multinucleated giant cells and
(2) intranuclear Cowdry bodies
64
cryoglobulinemia associated w/
associated w/ hep C infection.
cold-precipitable serum proteins that contain immunogloblins.
65
heterophile Ab test for EBV during latent infection
will NOT be positive.
latent infection: perisstence of full viral genome in B cells, but..
NO full virion replication
NO lytic release
SPARSE expression of viral proteins
66
hemadsorption of virally infected cells onto RBCs suggests
hemaggltins or glycoprotein expression on host cell. associated w/ influenza and parainfluenza viruses.
67
carbamazepine is first line for... (3) function?
increase Na+ channel inactivation..
partial simple
partial complex
tonic clonic
68
feared complications of carbamazepine
agranulocytosis or aplastic anemia
69
side effects of ethosuximide?
block thalamic T-type Ca2+ channels
```
EFGHIJ
ethosuximide
fatigue
GI upset
headache
itching
steven-johnson
```
70
characterize absence seizures
generalized, nonconvulsive. episodic loss of awareness (<10sec).
associated with 3 Hz generalized spike & slow wave EEG.
rx: ethosuximide & valproic acid
71
methyphenidate used for (2)
narcolepsy and ADHD
72
HIV gp120 important for? gp41?
gp 120: docking glycoprotein: viral adherance
| gp 40: transmembrane: fusion & entry
73
HIV early coreceptor? late?
early coreceptor: CCR5
late: CXCR5
both on T cells (CD4+).
CCR5 on macrophages
74
enfurvirtide binds to..
gp41, prevent fusion
75
methionine processing (4 major products in cycle)
(1) methionine
(2) s-adenosyl methionine
(3) s-adenosylhomocysteine
(4) homocysteine
76
fates of homocysteine (2)
(1) converted to methionine (gains methyl group_
- requires B12 (methylcobalamin -> cobalamin) and methyl-THF -> THF
- via homocysteine methytransferase// methionine synthase
(2) converted to cystathionine.
- requires B6 and serine
via cystathionine synthetase
cystathione -> cysteine
via cystathionase
requires B6
77
three ways to get homocysteinuria (3)
1. cystathionine synthase deficiency
(rx: reduce methionine. supplement B12, folate, and cysteine)
2. decreased affinity for cystathionine synthase for pyridoxal phosphate B6
(rx: more B6 and cysteine)
3. homocysteine methyltransferase / methionine synthase deficieny
(rx: supplement methionine)
78
presentation of homocysteinuria
intellectual disability, osteoperosis, tall stature, kyphosis, lens subluxation (down and in)
** arterial and venous thrombosis --> stroke and MI
note: marfanoid! like marfans (genetic heterogenity)
79
B12 specifically (i.e. no folate) needed for what pathway
methylmalonyl-CoA --> succinyl-CoA (methylmalonyl CoA isomerase)
succinyl-CoA --> myelin, TCA, and heme
methylmalonyl-CoA comes from odd chain fatty acid oxidation & branched-chain amino acid oxidation
80
kussmaul's sign
paradoxical increase in JVP with inspiration
found in patients w/ CHRONIC constrictive pericarditis -- takes months/years to develop
81
S3 suggests (2)
(1) rapid rate of diastolic ventricular filling w/ large volume of blood and/or
(2) reduced ventricular complicance
82
pulsus paradoxus
drop in systolic BP of 10mmHg or more in inspiration.
exaggeration of a normal physiological response
seen in cor pulmonale, chronic constrictive pericardial disease, and tamponade
83
pericardial knock
in chronic constrictive pericarditis.
brief, high frequency precordial sound heart in early diastole (shortly after S2). early than an S3 even. can be confused w/ opening snap.
84
acute pericarditis form. sign?
usu fibrinous or serofibrinous. pericardial friction rub: high pitched, leathery, scratchy
85
tracheal deviation towards opacified lung? away from opacified lung?
tracheal deviation away from lucent lung?
towards opaque: atelactasis (lung volume loss, i.e. bronchogenic carcinoma occluded airway --> atelactasis)
away opaque: pleural effusion
away lucent: pneumothorax
86
radiographic signs of PE
westermark sign -- lucent region due to oligemia distal to PE
hampton's hump -- opacity at phrenic angle
87
nephrogenic diabetes insipidus caused by lithium?
due to antagonism of vasopressin. resolves w/ discontinuation usu, though permanent is possible.
88
side effect of metformin
lactic acidosis
89
collagen synthesis main steps
ER:
(1) SYNTHESIS in ER: Gly-X-Y (proline & lysine usu)
(2) HYDROXYLATION of proline & lysine in ER ( vit C dep hydroxlyation)
(3) GLYCOSYLATION of lysine in ER
(4) FORMATION of procollagen in ER (hydrogen and disulfide bonds between alpha-fibrils)
(5) EXOCYTOSIS
(6) CLEAVAGE of N & C terminal disulfide linkages (procollagen to insoluble tropocollagen)
(7) COLLAGEN formation-- linking lysine to hydroxylysine residues (lysyl-oxidase Cu2+ dependent)
90
uric acid ppts at what pH
acidic pH (prone to ppt at acidic DCT and collecting ducts)
91
which kidney stones ppt at acidic pH? basic?
acidic pH: calcium oxalate, uric acid, and cystine
basic pH: calcium phosphate, and AMP (phosphates)
92
```
shape of..
calcium stones
AMP stones
uric acid stones
cysteine stones
```
calcium: envelope or dumbell
AMP: coffinlid
uric acid: rhomboid or rossettes
cysteine: hexagonal
93
AMP stone producing bacteria
proteus mirabilis or vulgaris
staph
klebsiella
(hydrolyze urea to ammonia)
94
what drug signicantly decreases heart failure progression & all-cause mortality in patients w/ CHF?
beta-blockers (carvedilol -- block alpha & betas)
decrease cardiac rate (slow rate & decrease afterload)
95
diabetic mother --> (2)
caudal regression & transposition
| drag queens & trans
96
drugs for congestive heart failure (esp those that decrease mortality)
ace inhibitors, ang II blockers, digoxin
MORTALITY HELPERS:
(1) beta blockers (carvedilol), (2) spironolactone (block aldosterone mediated remodeling
thiazide/loop diuretics for symptoms
hydralazine WITH nitrates reduce symptoms and mortality in selet group (not nitrates alone)
97
milrinone
phosphodiesterase inhibitor, increases contractility and reduces both prelaod and afterload.
short-term therapy
98
cystinuria
autosomal recessive.
common 1:7000
hereditary defect in amino acid transporter for cysteine, ornithine, lysine, and arginine.
COLA -- dibasic amino acids
in PCT and intestine
rx: alkalinization (via potassium citrate, acetazolamide) and chelating agents that increase solubility, good hydration.
diagnostic: urinary cyanide-nitroprusside test
99
sodium cyanide + sodium nitroprusside in urine --> red purple?
cystinuria
defects sulhydryl groups
100
hexagonal stones pathognomonic for..
cysteinuria!
101
peaked T waves
hyperkalemia
102
chemo for high grade lymphoma, leukemia, or any other cancer w/ rapid cell tunover, substantial tumor burden, or sensitivity to chemo can result ...
TUMOR LYSIS --> hyperuricemia --> renal impairment
103
reducing risk for tumor lysis?
aggressive fluid hydration
| allopurinol or rasburicase (reduce uric acid levels)
104
rasburicase
recombinant version of URATE OXIDASE (in nonhuman mammals)
convert uric acid --> allantoin. 5-10x more soluble that uric acid
effective in preventing and treating hyperuricemia & renal issues with tumor lysis
105
denosumab
Ab against RANK-L
prevent osteoclast activation
106
N-acetylcysteine (4)
(1) enhances glutathione production
(2) conjugates toxic NAPQI metabolites
(3) mucolytic
(4) prevents radiocontrast-induced nephropathy in patients w/ renal insufficiency
107
probenicid
uricosuric agent: increases excretion of uric acid in urine.
rx: for gout and hyperuricemia. but only effective if have good renal function. NOT used for patients at risk for nephrolithiasis or uric acid nephropathy
108
NEW findings in patient w/ acute left ventricular failure?
CHRONIC/later findings?
new: pulomary edema: interstitial & alveolar edema
prior episodes: hemosiderin-containing macrophages in alveoli (siderophages or heart failure cells
109
hemosidering-containing macrophages in alvoli suggest
prior / chronic episodes of pulmonary congestion and edema that arose due to CHRONIC left heart failure.
erythrocytes extravasate into alveoli (increased intravascular pressure in pulmonary capillaries). macrophage eat and accumulate hemosiderin
110
side effect of ethambutol
optic neuritis -- decreased visual acuity, color blindness, central scotoma
111
side effects with isoniazid
peripheral neuropathy and hepatoxicity
INH
112
gatifloxacin toxicity
hypoGlycemia
113
cipro toxicity
tendon rupture
114
B cell precursors proliferate and mature in..
BONE MARROW (undergo VDJ recombtination etc)
115
B cell meet antigen & undergo somatic hypermutation & isotype switching in..
germinal centers of lymph node
116
what happens in lymph node germinal center
(1) isotype class switching
(2) affinity maturation (somatic hypermutation)
(3) antibody production
117
where does VDJ and VJ recombination occur?
bone marrow! gives B cell initial specificity
-- more specific in germinal centers w/ somatic hypermutation & isotype switching
VDJ - heavy chain
VJ - light chain
118
worst prognostic factor in alcohol-associated hepatic injury?
- prolonged PT (reduced synthesis of factors)
- less albumin
reduced SYNTHETIC fxn
119
progression of alcohol-related hepatic injury
```
alcoholic stetosis (reversible)
alcoholic hepatitis (reversible)
alcoholic cirrhosis (irreversible)
```
120
hepatic injury signs?
increased transaminases & bilirubin
121
ALP elevated: biliary or bone?
check serum GGT (gamma glutamyl transferase)
elevated in biliary injury
122
thrombocytopenia in alcoholics due to..
direct toxic effects of alcohol on bone marrow & hypersplenism // splenic sequestration
123
immediate risk of warfarin
procoagulant -- esp in protein C deficiency --> hypercoagulable state w/ thrombotic occlusion of microvasculature and skin necrosis
rx: FFP
124
impaired absorption of B12 on schilling test that is not corrected w/ instrinsic factor?
malabsorption syndrome (like celiac or diphyllobothrium latum infxn)
125
reactive arthritis joint aspirate
STERILE. 'reactive' not 'infectious'
though it results from nongonococcal urethritis (chlamydia, or GI: camplyobacter, shigella, salmonella, yersinia, bartontella
can't see, can't pee, can't climb a tree
conjunctivitis, urethritis, arthritis
126
ecthyma grangrenosum
skin finding associated w/ pseudomonas aeruginosa
vascular destruction and cutaneous necrosis
perivascular bacterial invasion of arteries and veins in dermis and subcutaneous tissue. subsequent release of exotoxins that are destructive to human tissue.
release:
- exotoxin A (protein synth inhib)
- elastase (damages vasculature)
- phospholipase C (degrades cellular membrane)
- pyocyanin (generates reactive oxygen species)
127
persistant colonization w/ pseudomonas aeruginosa due to..
biofilm production (esp in chronic pneumonia in CF patients)
128
erysipelas
unique form of skin infection
causes lesions involving superficial layers of skin. results in painful erythematous plaques w/ raised and well-demarcated borders
strep pyogenes
129
liver mass w/ increasesd aFP
hepatocellular carcinoma
130
how does hepatitis B increase development of hepatocellular carcinoma
integration of viral DNA into genome
viral HBx triggers
(1) IGF II
(2) IGF-1 receptors
(3) inhibit p53
(4) general state of inflammation
131
rx for new onset diabetes type 1 (DKA)
regular insulin!
1 bolus, then continuous intravenous regular insulin
132
monomeric insulin. rapid acting
lispro, aspart, glulisine
do not polymerize -- rapidly absorbed after subcut injection
start 15min --> peak 45-74min.
133
rx postmeal hyperglycemis
rapid acting insulin (lispro, aspart, glulisine)
134
NPH
crystalline suspension of insulin w/ protamin and zinc, prolongs its actions
starts ~2hrs, peaks 4-12 hrs, last 18
135
determir
long acting insulin. fatty acid bound to one of the lysine on amino acid. allows albumin binding & slow dissociation.
starts working in 2 hrs, peaks 3-9, lasts 24
136
glargine
long duration action insulin. pH of 4. forms microprecipitate in subcutaneous tissue after injection. very slow release. 24 hrs
137
cachexia
syndrome of anorexia, malaise, anemia, weight loss, generalized wasting due to underlying disease
138
what cytokine produces cachexia
TNF-alpha
aka cachectin
made by macrophages in response to infxn as well as neoplastic cells
139
IL-1 and TNF-alpha in bacterial infection?
symptoms of septic shock. hepatic release of acute phase reactants: C-reactive protein, fibrinogen.
140
TNF-alpha cachexin effects
- hypothalamus -> appetite supprssion
- inhibit lipoprotein lipase
- increase insulin resistance of peripheral tissue
141
mallory bodies
intracytoplasmic eosinophilic inclusions -- alcoholic hepatitis
142
presentation of acute hepatitis B infection
incubation 30-180 days
sexual, parental, vertical tranmission
insidious onset:
"serum-sickness" like. malaise, fever, skin rash, pruritis, lymphadenopathy, join pain.
eventually SIGNIFICANT elevation in ALT > AST, rise in bilirubin, and ALP
143
presentation w/ acute hepatitis C
mild. patients usu asymptomatic. some have malaise, nausea, right upper quadrant pain.
144
hepatic steatosis affects which part of liver..
alcohol, reversible.
usu centrilobular.
macrovesicular steatosis
145
liver enzymes in hemachromatosis
MILDLY elevated
146
moldy grains..
aspergillus flavus & aspergillus parasiticus, grow on corn, soybeans, peanuts.
AFLATOXIN! (b1 most common & toxic)
increase risk of hepatocellular carcrinoma
aflatoxin-induced p53 mutations. classic G:C --> T:A in codon 249
