test #38 4.28 Flashcards Preview

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Flashcards in test #38 4.28 Deck (130):
1

triple test (maternal serum)

1. AFP
2. estriol
3. hCG

between weeks 16-18
abnormal values --> ultrasound
if no abnormalities found --> amniocentesis

2

AFH in triple test? elevated? low?

synthesized by fetal liver, GI tract, and yolk sac (early gestation only).

maternal serum aFP levels increase w/ gestation age

elevated:
1. dating error (underestimation)
2. neural tube defects
3. anterior abdominal wall defects (omaphalocele, gastrochisis)
4. multiple gestatoin

decrease: Down's syndrome

3

most common cause of elevated AFP in triple test?

dating error (underestimation of gestational age).

confirm w/ ultrasound

4

estriol levels in triple test? decreased levels suggest?

reflect placental and fetal function (both necessary for synthesis)

decrease:
1. placental insufficiency

5

hCG in triple test? increased levels associated w/?

synthesized by trophoblastic tissue.

increased levels:
1. multiple gestation,
2. hydatidiform mole,
3. choriocarcinoma
4. down's syndrome

6

placental abnormalities & intrauterine growth retardation are associated w/ decreased..

estriol

placental insufficiency!

7

infection, pain, and sleep deprivation all increase..

blood glucose!

stress: increase catecholamines
(decreased insulin, increase glycogenolysis, increased gluconeogenesis)

8

isolation (defense mechanism

removing disturbing feelings from an event.

combat veterans who describes friends dying in cold and distant tones. isolating the fear and sadness from event

9

bifid carotid pulse w/ brisk upstroke "spike & dome" associated w.

hypertrophic obstructive cardiomyopathy
(collapse in pulse, followed by secondary rise)

10

three cytogenetic abnormalities that can lead to downs syndrome

1. trisomy 21: meotic nondisjunction (usu mama)

2. unbalanced robertsonian translocations (2-3%)
- normal number of chromosomes, but extra arm of chromosome 21 is attached to another chromosome

3. mosaicism: one w/ normal genotype, one with trisomy 21
-postfertilization mitotic error

11

uniparental disomy

when fetus inherits two copies of homologous chromosomes from one parent and no copy from other parent

(occurs in complete hydatidiform mole)

consider when child inherits a recessive condition when only 1 parent is carrer

12

heterodisomy and isodisomy

heterodisomy: uniparental disomy in meiosis I

isodisomy (homozygous): in meiosis II or postzygotic duplicatino of one & deletion in one

13

cytokines involved in asthma

IL4: class-switch to IgE
IL5: recruit eosinophils
IL10: block Th1, encourage Th2

14

charcot-leyden crystals

asthma sputum: eosinophil membrane protein

15

TGF-beta is important for..

tissue regeneration and repair

16

anti-inflammatory cytokines

IL-10 and TGF-beta

17

loss of CNIII to the eye results in.. (3)

somatic:
1. ptosis (levator palpebrae)
2. down & out (only maintain superior oblique and lateral rectus)

2. loss of iris spincter
(fixed dilated)

3. loss of acommodation

18

describe light pathway (reflex)

afferent in one eye:

ipsilateral optic nerve -> bilateral post optic chiasm -> bilateral pretectal area -> bilateral edingerwestphal nucleus

efferent:
bilateral edingerwestphal nucleus -> travel w/ oculomotor n -> bilateral ciliary ganglion -> bilateral pupillary sphincter

19

2 ways to get lung abscess

1. aspiration of oropharyngeal contents (most common)

2. right sided endocarditis -> septic emboli

20

Marcus Gunn pupil

defect in CN II
"swinging flashlight test"

affected eye will have consensual pupillary constriction, but will appear to 'dilate' when light is on affected eye

-- can't detect light

21

differentiate lesion in LGN and optic tract

both will have contralateral hemianopsia

optic tract: has Marcus Gunn pupil (loss of direct pupillary constriction w/ light)

LGN: light reflex should be fine (does not go through LGN, instead straight to pretectal -> edingerwestphal -> ciliary ganglion -> iris sphincter

22

Marcus-Gunn pupil in optic nerve lesion? optic tract?

optic nerve: marcus gunn pupil when light is shone into affected eye (IPSILATERAL relative afferent pupillary defect)

optic tract: marcus gunn pupil when light is shone on eye CONTRALATERAL to side of lesion.

bc nasal fibers contribute more to prectal afferents. optic tract will have more contralateral 'nasal' fibers. less afferents

both have contralateral homonymous hemianopsia

23

rabies virus is..

killed vaccine

24

Live vaccines (6)

live! small yellow chickens get vaccinated w/ mmr and sabin's polio! it's INcredibly

1. smallpox
2. yellow fever
3. VZV chicken pox
4. MMR (measles, mumps, rubella)
5. sabin's polio (IgA and IgG)
6. infuenza intranasal

25

Killed vaccines (4)

SalK = killed
RIP Always

1. rabies
2. influenza (intramuscular)
3. salk polio
4. hepatitis A

26

recombinant vaccines (2)

1. HBV (recombinant HBsAg)
2. HPV (6, 11, 16, 18)

27

path of rabies viruses

deposit in wound:

rabies binds to nicotinic AchR in striated muscle -> binds NCAM -> enters motor neuron // DRG?

- rabies virus travels retrograde via peripheral nerves to DRG
- then to brain
- massive replication in CNS
- rabies then spreads to other organs via neural pathways

28

recommendation for rabies vaccine

prophylatic for certain populations: veterinarians, 30+ days in country w/ lots of rabid dogs)

inactivated (killed) virus w/ beta-propiolactone

29

clinical presentation of rabies

restlessness, agitation, dysphagia progressing to coma 30-50 days following exposure

30

chromosome of NF2

chr. 22

31

chromosome of p53

chr. 17

breast, sarcoma, brain tumor, leukemia, adrenocortical tumor

32

gene implicated in NF-1

von Reclinghausen disease, chr. 17

tumor supressor gene: neurofibromin

(cafe au lait, neurofibromas, lisch nodules)

33

gene implicated in NF-2

central neurofibromatosis, chr. 22

tumor supressor gene: merlin

bilateral acoustic neuromas

34

chromosome of APC

chr. 5

35

chromosome of Rb

chr. 13

osteoscarcoma, retinoblastoma

36

chromosome of VHL

chr. 3

renal cysts, renal cell carcinoma, hemangioblastoma of cerebellum and retina

37

ureteral constriction / obstruction causes..

decreased GFR, normal RPF = decreased filtration fraction

FF = GFR/RPF

38

amino acid w/ 3 titratable protons (3 pKA) (7)

histidine, arginine, lysine, aspartic acid, glutamic acid, cysteine, tyrosine

39

histidinemia

rare autosomal recessive disorder

deficience of histidase (required for catabolism of histidine)

speech defects, psychomotor & generalized retardation, emotional disturbance

most frequent inborn metabolic error in Japan

40

how much coronary blood flow occurs in systole

30%

41

critical factor in determining coronary blood flow, esp in exercise

duration of diastole

42

single most important risk factor for development of aortic dissection

hypertension!

(next: cystic medial degeneration, connective tissue disorder)

43

diabetes mellitus is an important risk factor for developing which 2 major diseases

1. atherosclerosis
2. hypertension

44

most impt factor for development of aortic aneurysm?

atherosclerosis (high cholesterol)

45

what 4 things increase risk for atherosclerosis (2)

1. high cholesterol
2. smoking
3. HTN
4. diabetes mellitus

46

t. pallidium infects what part of aorta

vasa vasorum in adventitia of ascending thoracic aorta

weakens wall -> predispose to ascending aortic aneursym

dissection = rare w/ syphillis

47

rx for status epilepticus (4 steps)

1st line: IV lorazepam
2nd. simultaneous phenytoin.

if still seizing:
3rd: phenobarbital

if still seizing
4: intubate / general anesthesia

48

definition of status epilepticus?

generalized tonic clonic seizure lasting for more than 30min w/o return to consciousness.

49

mechanism of valproic acid

increase Na+ channel inactivation
block NMDA receptor
affect K+ current
GABA Cl- receptors

50

rx for myoclonic seizure

valproate -> first line

51

definition of myoclonic seizure

repetitive seizures, consisting of brief, symmetric muscular contractions w/ loss of body tone causing patient to fall or slump forward.

usu morning and ppt by stress / sleep deprivation

52

myoclonic seziure vs. tourette tics

tourette: motor tics are nonrhythmic, temporarily suppressible, often preceeded by urge to make stereotyped movement

53

rx for tourette

typical & atypical antipsychotics, like haloperidol

54

describe tonic clonic

generalized tonic extension, followed by clonic rhythmic motions

rx: PVC

55

which DNA pol has 5'-3' exonuclease activity

DNA pol I (remove primer)
also have 3'-5' corrective abilities

56

cyanide toxicity

binds to many iron containing enzymes.

most importantly: cytochrome a-a3 complex (in complex IV)

toxicity: inhibits aerobic metabolism --> rapid death

57

complex I of ETC is known as? inhibited by?

NADH oxidase
inhibited by: rotenone

58

complex II of ETC is known as? inhibited by?

succinate dehydrogenase
nothing!

59

complex III of ETC is known as? inhibited by?

has coenzyme Q
blocked by amtimycin A

60

complex IV of ETC known as?
inhibited by?

has cytochrome C (between it and complex III)

cyanide + CO

cytochrome a a-a3 complex blocked by cyanide



61

complex V also known as? inhibited by?

ATP synthase

oligomycin

62

why make methemeglobin in cyanide toxicity (w/ nitrites)

methemoglobin can't bind oxygen, but can bind & sequester cyanide (keeps poision away from mitochondria, etc)

cyanide binds ferric iron more than mitochondrial cytochrome enzymes

63

Dubin-Johnson problem? gross? histology?

defect in hepatic excretion of (conjugated) bilirubin across canalicular membrane.

gross: liver is black

histology: features are normal, though dense pigment of epinephrine metabolites within lysosomes can be seen

64

histology of liver: dense pigments of epinephrine metabolites in lysosomes?

dubin-johnson

65

diagnosis of dubin johnson

conjugated hyperbilirubinemia w/ direct bilirubin > 50%

otherwise normal liver function profile must be present

confirmation: unusually high levels of coproporphyrin I

66

Ras-MAP kinase signalling cascade

growth factor
autophosphorylation of RTK
--> interact w/ SH2 domain protein & SOS protein

leads to Ras activation (G protein) + GTP
--> phosphorylates Raf kinase

all leads to MAP kinase (enters nucleus to influence gene transcription

67

what kind of protein is Ras

G-protein, activated w/ RTK

68

PI3K pathway associated w.

PI3K / Akt / mTOR

69

activation and inactivation of RAS

activated by RTK
inactivated by GAP (GTPase activating protein) 00> hydrolysis

70

ETEC toxin is like..

cholera toxin, especially heat labile

(heat labile & stabile toxin)
plasmid encoded

LT -- like cholera (activates Gs --> adenylate cyclase --> cAMP)

ST -- increase cGMP (binds & activates guanylate cyclase on apical membranes of gut mocsal cells)

FIMBRIAE // pilli allow for adhesion

watery diarrhea

71

invasive gastroenteritis (5)

Salmonella
Shigella
EIEC
Camplyobacter jejuni
Entamoeba histolytica

72

stacked-brick intestinal adhesion

characterestic of enteroaggregative E. coli
EAEC

adhere to jejunal, ileal, and colonic mucosa

do not invade

persistent diarrhea in infants in developing countries

73

2 risks w/ fibrates

1. myositis (esp w/ statin)
2. cholesterol stones

use to treat hypertriglyceridemia

74

side effect w/ ezetimibe?

rare LFT increase, diarrhea

75

side effect w/ cholestyramine?

taste bad
GI discomfort
decrease absorption of fat soluble vitamins
maybe cholesterol gallstones

76

statin toxicity

hepatoxicity
myositis (esp w/ niacin & fibrates)

77

what combination of lipid lowering agents increases myositis

statin + fibrate + niacin

78

hydroxymethylglutaryl coenzyme A reductase

HMG CoA reductase

convert HMG CoA to cholesterol

79

statin w/ highest myopathy

simvastatin

80

jimson weed is similar to

atropine! causes gardener's mydriasis (anticholinergic crisis)

81

blind as a bat, mad as a hatter, red as a beet, hot as a hare, dry as a bone, the bowel and bladder loose their tone, and the heart runs alone

anticholinergic crisis

- mydriasis & cylcloplegia
- CNS hallucinations, agitation, delirium
- hyperthermia --> cutaneous vasodilation
- loss of secretions (salvation, lacrimation, sweating)
- decreased GI motility & secretion, urinary retention via detrusor relaxation & constriction of external urethral sphincter
- tachycardia (diminshed vagal tone)

82

clasp knife spasticity

sign of upper motor neuron lesion:

initial jerking resistance to passive extension followed by sudden release of resistence

due to lack of UMN inhibitory control on spine muscle stretch reflex arc

cortisospinal tracts of spinal cord, medulla, pons & midbrain, internal capsule, precentral gyrus

83

'watershed areas' of bowel (2)

splenic flexure: between SMA and IMA

distal sigmoid colon: between IMA and hypogastric

84

side effects of colchicine?

binds to tublin & blocks its polymerization

GI ISSUES: many get diarrhea. some, nausea and vomiting (effects on gastric mucosa)

recommended for patients who cannot take NSAIDs (i.e. renal failure, peptic ulcer disease)

85

which drugs are contraindicated in acute gouty arthritis?

probenecid and allopurinol!

can ppt acute attacks!

86

describe thiopental mechanism

used for INDUCTION.
highly lipid soluble.
equilibrates w/ brain within 1 minute.

accumulation in brain followed by rapid "redistribution" into skeletal muscles & adipose tissue (within 5-10min)

87

what is responsible for rapid awakening after thiopental

REDISTRIBUTION (into skeletal and adipose tissue)

NOT metabolism.

88

carcinoid tumor on histology

eosinophilic cytoplasm, oval-to-round nuclei

minimal to no variation in shape and size of tumor cells.

gland, nests, rows, or sheets may form

EM: dense core granules

ECL cells

89

APUD system

Amine Precursor Uptake and Decarboxylation

the ECL cells (that become malignantly transformed into carcinoid tumors)

90

most common location for carcnoid tumor

ileum.

also appendix and rectum.

91

meningiomas arise from cells of..

arachnoid villi

92

Arnold-Chiari malformation.

type I vs. type II

congenital issue
underdeveloped posterior fossa

parts of cerebellum & medulla herniate through foramen magnum

type 1:
- low lying cerebellar TONSILS extend below foramen magnum into vertebral canal
- infant: asymptomatic
- adult: headache & ataxia

type 2
- more severe; evident in neonate
- abnormally formed cerebellum & medulla
- TONSIL and VERMIS herniate through
- hydrocephalous (aqueductal stenosis) & lumbosacral myelomeningocele (paralysis)
- medulla compression: dysphagia, dysphonia, stridor, apnea

93

Dandy walker

agenesis of cerebellar vermis w/ cystic enlargement of 4th ventricle (occupies the enlarged posterior fossa)

associated w/ spina bifida and hydrocephalous

94

all antidepressants carry risk of..

inducing mania in susceptible patients!
especially TCA and venlafaxine

95

carbamazepine, lithium and valproate as all

mood stabilizers!

used in acute mania and maintence of bipolar disorder

96

genetic components of type I and type II diabetes

DM2: strong, but we don't know gene
DM1: weak, but we know MHC related

twin studies
50% DM1
80% DM2

genes:
DM1: polymorphism in MHC (HLA-DQ and DR)

DM2: polygenic, unknown

97

HLA-DQ & DR associated with

type 1 diabetes mellitus

(type 2: polygenic, unknown)

98

genetics of friedrich's ataxia

autosomal recessive
chr. 9
frataxin protein -- essential for normal mitochondrial fxn

trinucleotide repeats in frataxin gene -> diminished levels pf protein

99

presentation of friedrich's ataxia

1. ascending / descending spinocerebellar tract degeneration --> ATAXIA
2. degeneration of dorsal columns and DRG --> loss of position & vibration sensation
3. kyphoscoliosis and foot abnormalities: characteristic skeletal deformity
4. hypertrophic cardiomyopathy
5. DM in 10%

100

diffuse medium-sized lymphocytes & high proliferation index (represented by high Ki-67 fraction --> 100%)

burkit lymphoma
EBV related
t(8,14) overexpression of c-MYC

101

50% of B-cell lymphoma and almost all primary CNS lymphoma in HIV infxn associated w/

Burkitt Lymphoma

102

4 stages of syphillis

PRIMARY: chancre
1-3wks after contact
resolves in 3-6 wks

SECONDARY: bacteremic stage.
5-10wks following chancre resolution
diffuse macular rash including palms and soles
condylomata lata

LATENT: asymptomatic period.
early latent: 1 year after resolution of secondary symptoms
late latent: more than 1 yr after asymptomatic state

TERTIARY: years after infection.
neurosyphillis: subacute meningoencephalitis, tabes dorsalis, etc

gummas: commonly cutaneous, but also subcut, bones, liver, etc

aortitis: vasovasorum of ascending sorta

103

painless induration on genitals w/ headaches & memory loss

NOT a chancre bc neuro involvement!

has to be a gumma

104

describe a chancre

painless ulceration w/ raised, indurated borders.

develops at site of t. pallidum inoculation in 1-3wks. resolves in 3-6 wks.

PRIMARY SYPHILLIS

105

condylomata lata

large gray wart-like growths that occur in genital / perineal regions

typical manifestation of secondary syphillis

106

gumma

painless, indurated granulomatous lesions that progress to white-rubbery lesions that may ulcerate.

commonly cutaneous, but also on subcutaneous tissue, bones, liver, other organs.

TERTIARY SYPHILLIS

107

positive VDRL and pleocytosis in CSF

diagnostic of NEUROSYPHILLIS (part of tertiary syphillis, w/ gummas)

NOT primary.

108

granuloma inguinale

STD
klebsiella granulomatis

inguinal swelling, ulcers, abscesses, fistulas.

gram stain: cells w/ rod-shaped intracytoplasmic inclusions: Donovan bodies

109

condyloma accuminata

anogenital wars by HPV (6, 11)

110

painless ulcer w/ painful lymphadenopathy

lymphogranuloma venerum
C. trachoatis (L1-L3)

111

chancroid

painful genital ulcer and inguinal adenopathy

haemophilus ducreyi

112

donovan bodies

granuloma inguinale
klebsiella granulomatis

113

interferon alpha & beta

innate host defect
secreted by virally infected HOST cells

act on locally unaffected cells "priming them" for viral defense

when infected, viral nucleic acids will activate

HALT PROTEIN SYNTHESIS

1. RNAse L: degrade viral & host mRNA

2. protein kinase: inhibit viral/host protein synthesis

essentially results in apoptosis (interrupting amplification)

114

type II interferon (IFN-gamma)

secreted by Th1 and NK cell mainl

promote th1 differentiation, increase expression of class II MHC on APC, and improve intracellular killing of macrophages

115

type 1 and 2 interferons generally.

increase MHC class I expression
increase NK cell
increase CD8+ cytotoxic

all aim to increase amt of virally infected cells that undergo apoptosis

116

local pleural thickening w/ calcification (particularly of parietal pleura of posterolateral mid-lung zones & diaphragm)

hallmark of asbestosis

117

pulmonary manifestation of silicosis

nodular densities & eggshell calcifications of hilar nodes

118

pulmonary berylliosis

closely resembles sarcoidosis

nodular infiltrates, enlarged lymph nodes, non-caseating granulomas

119

ITP in children vs. adult

children: acute & self-limited
adult: insidious & chronic course

120

ITP considered when you DON'T have

signs & symptoms of TTP/HUS, pancytopenia, marrow failure, or splenomegaly (would be sequestration)

121

what constitutes crescent in RPGN?

FIBRIN & monocytes

also: macrophages, proliferated glomerular parietal cells

eventually oblterate bowman's space

122

influenza A infection

can affect 50-75% of school-aged children, often pass on to family.

-abrupt onset fever, headache, myalgia, malaise
-gradually improve over 2-5 days.

123

staph aureus pneumonia

bronchopneumonia:
most common cause of SECONDARY pneumonia

(bacterial pneumonia on top of influenza)
- recurrent fever, dyspnea, productive cough. see consolidation.

ELDERLY, particularly at risk.

124

most common agents responsible for secondary bacterial pneumonia

1. strep pneumoniae
2. staph aureus
3. haemophilus influenzae

125

listeria in neonates

septicemia and purulent meningitis in neonates

126

klebsiella pneumonia is most commonly responsible for..

nosocomial UTI
nosocomial pneumonia
pneumonia in alcoholics & IV drug

127

mycobacterium scrofulaceum

cervical lymphadenitis in children

128

mycobacterium kanasasii

pulmonary TB like symptoms

129

effect modification

effect of main exposure on an outcome is modified by another variable

a chemo for breast cancer that only helps smokers

not a bias.

130

MCD is thought to be caused by..

primary defect in immunologic function
(associated w/ respiratory infection, immunization, atopic disorders; helped by steroids)

overproduction of IL-13 --> damage podocytes.

selective albuminuria