test #30 4.20 Flashcards Preview

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Flashcards in test #30 4.20 Deck (146):
1

opsoclonus-myoclonus syndrome

non-rhythmic conjugate eye movement w/ myoclonus

2

non-rhythmic conjugate eye movement w/ myoclonus?

opsoclonus-myoclonus

3

most common extracranial childhood tumor

neuroblastoma, usu from adrenal medulla

4

Wilm's tumor vs. neuroblastoma

neuroblastoma: firm, irregular mass. cross midline.

wilm's tumor: smooth and unilateral

5

presentation of neuroblastoma?

child ~2y/o. retroperitoneal mass, HTN.

6

neuroblastoma mets

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

urine w/ neuroblastoma

increased HVA in urine

8

genetics of neuroblastoma

n-myc amplification

9

prognosis

better if <1 y/o
worse with higher n-myc amplification

10

formation of annular pancreas

ventral pancreatic bud cleaves into two parts, fuse w/ dorsal bud on either side -- can compress duodenal lumen

11

heteroplasmy

mixture of two types of genetic material (i.e. inherit some normal & mutated mitochondria)

12

mitochondria inheritance

ovum has many mtDNA. few copies in sperm are lost during fertilization.

variability bc during mitosis, mitochondria are RANDOMLY distributed between daughter cells

13

characterestics of mitochondrial diseases

1. affect both male & female w/ equal frequency
2. variable degrees of severity: due to heteroplasmy

14

three mitochondrial diseases

1. leber hereditary optic neuropathy
2. myoclonic epilepsy w/ ragged red fibers MERRF
3. mitochondrial encephalomyopathy w/ lactic acidosis and stroke-like episodes MELAS

15

myoclonic seizures and myopathy associated w/ exercise. skeletal biopsy w/ irregularly shapped muscle fibers (ragged red)

myoclonic epilepsy w/ ragged red fibers.

mitochondrial disease

16

leber hereditary optic neuropathy

mitochondrial disease.

bilateral vision loss

17

seizure disorder, several stroke-like episodes, increase lactic acidosis.

affected siblings w/ variable degrees of severity

MELAS

mitochondrial encephalopmyopathy w/ lactic acidosis & stroke-like episodes (MELAS)

18

variable expressivity vs. variable degrees of severity

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

gram negative lactose non-fermenters?

oxidase positive: p. aeruginoas

oxidase negative: shigella, salmonella, proteus

20

differentiate shigella vs. salmonella & proteus in culture

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

essential pathogenic mechanism for shigella

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

which enteric bacteria penetrate mucosa & proliferate in mesenteric nodes?

salmonella typhi and yersenia enterocolitica.

23

which bacteria causes pseudoappendicitis?

yersenia enterocolitica. mesenteric lymph node infection, RLQ pain.

24

work of breathing is a balance between..

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