test #32 4.22 Flashcards Preview

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Flashcards in test #32 4.22 Deck (150)
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1
Q

when is hCG detectable

A

secreted by syncitiotrophoblasts.

zygote implants as blastocoele ~8 days

2
Q

when does zygote enter uterus

A

zygote enters uterus as 2-8 celled embryo / morula on day 3-4

3
Q

hCG production by embryo/zygote begins? in maternal serum

A

free-floating blastocyst in uterine secretes hCG ~6 days, but won’t enter maternal serum until implanatation.

no early than 6-11 days post ovulation in maternal serum (usu day 8)

4
Q

CMV retinitis

A

inflammatory vascular sheathing & hemorrhage

full thickness retinal necrosis & edema. eventually replaced w/ atrophic scar

can result in retinal detachment – tearing of thin atrophic scar that forms in areas of prior inflammation

5
Q

when does CMV infect HIV+ patients?

A

CD4 < 50 cells/uL

6
Q

flucytosine mechanism

A

converted to 5-FU by fungal cytosine deaminase.

causes RNA miscoding and inhibtion of DNA synthesis

7
Q

IFN-alpha used to treat (4)

A

(1) hep B and C
(2) hairy cell leukemia
(3) condyloma acuminatum
(4) Kaposi sarcoma

8
Q

pentamadine rx for?

A

pneumocystis pneumonia

9
Q

friedrich ataxia inheritence

A

autosomal recessive

10
Q

pathogenesis in friedrich ataxia? presentation

A

(1) posterior column and spinocerebellar tract degeneration
(2) loss of larger sensory cells of dorsal root ganglion

children 5-15 y/o w/ gait ataxia (wide-based gait w/ difficulty maintaining balance, progressively slow and clumsy

11
Q

5 symptoms associated w/ friedrich’s ataxia

A
  1. progressive ataxia of all 4 limbs, cerebellar dyfxn, early. degeneration of dorsal column – loss of position and vibration
  2. hypertrophic cardiomyopathy in more than 50% of patients –> cardiac arrhythmia and CHF
  3. skeletal abnormalities: kyphoscoliosis, pes cavus, hamemrtoes
  4. diabetes mellitus in about 10%
12
Q

most common cause of death in friedrich’s ataxia? (2)

A

cardiomyopathy

bulbar dysfxn (unable to protect airway)

13
Q

trinucleotide repeat of friedrich’s ataxia. chromosome? codes for?

A

autosomal recessive
chr. 9
GAA
codes for frataxin = iron binding protein

mitochondrial dysfunction

14
Q

eroded teeth enamel and enlarged, firm parotid glands, irregular menses (not amenorrhea though)

A

bullimia nervosa

amenorrhea = almost always in anorexia nervosa

15
Q

glucagon’s action in DKA

A

(1) stimulate ketoacid synthesis in adipose tissue
(2) increases glyocogenolysis
(2) gluconeongeisis
(4) lipolysis
(5) urea production

16
Q

JVP waves

A
peak: A
peak : C
dip: x
peak: V
dip: y

a: atrial contraction
c: bulging of tricuspid valve into atrium (isovol contraction)
x: opening of pulmonic valve / relaxation of atrial muscle
v: continuous flow of venous blood into atria
y: opening of tricuspid valve (passing emptying)

17
Q

sign of contrictive pericarditis on JVP wave

A

y descent is deeper and steeper on inspiration

18
Q

causes of (chronic) constrictive pericarditis

A

go from 1-3mm to 4-20mm thick. looks like thick line surrounded heart

caused by radiation therapy to chest, cardiac surgery, and TB

19
Q

evidence of ischemic heart disease on CT?

A

calcified vessels

20
Q

clinical signs of constrictive pericarditis

A

slowed progressive dyspnea, peripheral edema, ascites

21
Q

what provides nerves, arteries, veins, and lymphatics to ovaries

A

suspensory ligament

22
Q

broad ligament

A

mesoovarium that covers ovaries, uterine tube, ovarian ligament, round ligament of uterus, portion of suspensory ligament.

23
Q

blood supply and drainage of ovaries

A

gonads!
blood supply from aorta.
right drains to IVC
left to renal vein

24
Q

nervous supply to ovaries

A

from vagus n.

25
Q

common complication in pelvic surgery when ligating ovarian vessels

A

ligating ureter (traveling underneath)

26
Q

round ligament of uterus

A

courses through inguinal canal. links uterus to external genitalia. contains artery of sampson, which is rarely a source of blood.

also round ligament in liver

27
Q

ovarian ligament

A

contains no vessels. courses form uterine pole of ovary to body of uterus, just below uterus

28
Q

transverse cervical ligament, or cardinal ligament

A

extends from cervix and lateral fornix of vagina to lateral pelvic walls.

contains uterine artery!

29
Q

gingival bleeding, echymoses & petechiae, impaired wound healing. perifollicular hemorrhages w/ coiled (corkscrew hairs)

A

collagen problem.
scurvy: lysyl hydroxylase and proyl hydroxylase deficiency

requires vitamin C
occurs in rough ER

mutation:

  1. decreases amount of collagen secreted
  2. impairs triple helix stability
  3. impairs covalent cross link formation
30
Q

collagen mutation in ehlers-danlos (type I & II)

A

mutation in type V collagen

31
Q

defining characterestics of ehlers-danlos type I & II

A

joint hypermobility

hyperextensible, fragile, skin

32
Q

osteogenesis imperfecta mutation

A

type I collagen.

spontaneous fracture, bone & tooth malformation, blue sclerae

33
Q

how does dopamine come to inhibit prolactin secretion in pituitary

A

via tuberoinfundibular dopaminergic pathway – connect hypothalamus to pituitary gland

34
Q

mucicarmine stain

A

cryptococcus neoformans. detects polysaccharide capsule
(only one w/ capsule)

round yeast cells w/ narrow-based buds

(can cause pulmonary infxn first)

35
Q

blastomyces dermatididis on culture

A

lung & disseminated.

round yeast
broad-based budding
thick, doubly-reflective wall

36
Q

histoplasma on culture

A

TB pulmonary & disseminated

intracellularly within macrophages – small, ovoid, budding yeast cells

37
Q

coccidioides immitis

A

lung in competent.
disseminated in compromised.

large, irregularly sized, thick walled spherules w/ small, round endospores

38
Q

only pathogenic fungus w/ polysacch capsule?

A

cryptococcus neoformans!

red on mucicarmine stain.
clear in india ink.

39
Q

cystic degeneration of the putamen

A

many can cause. usmle = think wilson’s disease

40
Q

sudden cardiac death in youth? in adults?

A

youth: Vfib from hypertrophic cardiomyopathy
adult: 80% due to acute plaque change superimposed on coronaryatherosclerosis

41
Q

90% of cardiomyopathies are..

A

dilated cardiomyopathy! but only account for 10-15% of sudden cardiac death

42
Q

why do babies need brown fat (5% of their body mass)

A

susceptible to hypothermia:

  1. immature nervous system
  2. high body surface are to volume ratio
  3. decreased ability to shiver for heat production
43
Q

white vs brown fat.

A

white: one intracytoplasmic fat droplet

brown:
- several fat vacuoles,
- considerably more MITO (colour)
- higher oxygen requirement
- contains more capillaries

44
Q

how does brown fat make heat

A

uncouple electron transport and phosphorylation.

protons pumped out why electron transport chain return to matrix via mitochondrial matrix protein THERMOGENIN (uncoupler).

no ATP synthesizes, energy = heat

45
Q

ascending paralysis post febrile illness

A

guillian barre

46
Q

guillan barre is associated w/

A

young adults.
preceeded by upper respiratory or GI infection. could be after vaccine or allergic reaction.

strongly associated w/ campylobacter jejuni infection

47
Q

pathogenesis of guillan barre

A

ACUTE DEMYELINATING DISEASE. immune-mediated.

antibodies to infection cross-react w/ myelin of spinal roots & peripheral nerves.

48
Q

light microscopy of guillan barre

A

segmental demyelination of peripheral nerves. accompanied by endoneural inflammatory infiltrate – lymphocyte & macriohages

49
Q

endoneural inflammatory infiltrate =

A

guillan barre

50
Q

CSF in guillan barre:

A

increase protein, with normal/slightly elevated cell count

= ALBUMINOCYTOLOGIC DISSOCIATION

51
Q

polymyositis vs. guillan barre?

A

nerves are fine in polymyositis, despite weakness.

guillan barre – NO DTRs

52
Q

flat yellow spots on inner surface of aorta

A

fatty streaks

53
Q

fate of fatty streaks

A

earliest lesions in progression to atherosclerosis, BUT do NOT predict occurance or location of atheromatous plaques later in live.

in all individuals after age 10

often occur in regions not particularly prone to atheroma. frequently affect people/regions w/ low lifetime incidence of atheromatous plaques

54
Q

what are fatty streaks

A

intimal lipid-filled foam cells.
derivived from macrophage and smooth muscle cells that have engulfed LDL, entered intima through injured, leaky endothelium.

usu begin as multiple yellow spots (1mm in diameter) which form streaks.

NOT raised, so do NOT disturb blood flow.

NOT ALL PROGRESS to atheromas! common age 10 onwards. mostly consist of macrophages.

55
Q

nitric oxide originates from

A

amino acid arginine

56
Q

urea originates from..

A

arginine + aspartate

57
Q

heme originates from

A

succinyl-CoA and glycine

58
Q

creatine originates from

A

glycine + arginine + SAM

59
Q

GABA originates from

A

glutamate

60
Q

glutathione originates from

A

glutamate

61
Q

pyrimidines originate from..

A

glutamate + aspartate

62
Q

purines originate from..

A

glutamate + aspartate + glycine

63
Q

histidine originates from…

A

histamine

64
Q

dopamine pathway origination

A

phenylalanine -> tyrosine -> DOPA -> dopamine

65
Q

tryptophan makes.. (2)

A

tryptophan -> serotonin -> melatonin

&

tryptophan -> niacin

66
Q

tyrosine makes (2)

A

thryoxine & melanin

67
Q

which factors stimulate vasodilation of epicardial vessels?

A

acetylcholine, bradykinin, shear stress, serotonin, substance P.

all stimulates influx of Ca2+ in endothelium. turns on eNOS

eNOS:

arginine+ O2 -> nitric oxide + citrulline

NO from endothlium goes to smooth muscle cells in vasculature –> turns on guanylate cyclase to make cGMP – vasodilates

cGMP causes vasodilatoin bc protein kinase G reduces cytosolic calcium levels

68
Q

amino acid w/ adjunctive role in rx of conditions that improve w/ vasodilation

A

arginine! precursor to nitric oxide

69
Q

location of enhancers? promoters?

A

enhancers: increase rate of transcription intiation through protein binding & intxn w/ transcription factors bound to promoter sequences.

enhancer/repressors: anywhere: upstream. downstream, in gene, thousands bp away, sep chromosomes

promoter: binding site for transcription factor and RNA pol II.

two types of promoter:

  1. TATA (hogness) box: 25 nucleotides upstream from gene
  2. CAAT box, 70-80 bases upstream from gene
70
Q

tetanus route

A

clostridium tetani spores germinate in wound (low oxygen, high nutrients). u

pon bacterial cell autolysis, TOXIN is released and enters motor neuron (axon terminal).

TOXIN travels via retrograde transport to spinal cord, medulla.

ORGANISM stays at site of wound

71
Q

route of rabies virus

A

wound -> neuron axons -> salivary glands.

specifically: motor neuron -> retrograde into nerves of spinal cord -> into cerebellum, brainstem -> hippocampus.

from there -> within nerve axons –> tissue of salivary glands

72
Q

route of diptheria toxin

A

fibrinous exudate (pseudomembranous exudate) -> blood stream systemic circulation -> cortical neurons & cardiac cells

73
Q

pressure volume curve of lung & chest wall compliance.

alveolar transmural pressure
chest wall transmural pressure

intrapleural pressure?

A

lung transmural pressure: ALWAYS + (wants to collapse)

chest wall:
usually - (wants to expand,
except at maximal inspiration, will be +

when positive alveolar transmural pressure = negative chest wall transmural pressure –> airway pressure = 0 (functional residual capacity)

intrapleural pressure: always negative. at FRC (-5cmH20). in inspiration (-7.5cmH20) –> helps draw air into lungs

74
Q

explain why intrapleural pressure is always negative (even at 0 airway pressure)

A

recall: pneumothorax, make intrapleural pressure = 0 (atmospheric pressure)

this causes lung to collapse and chest wall to expand.

at FRC –> tendency of chest wall to expand and lung to collapse creates a negative intrapleural pressure of -5cm H20 (more negative when inspire)

75
Q

rx for amiodarone-induced hypothyroidism?

A

levothyroxine. typically continue.

always monitor TSH before giving amiodarone

76
Q

HIV associated esophagitis (3). distinguish?

A

cannot distinguish clinically. endoscopic & microscopic

(1) candida albicans
- patches of adherent, grey/white pseudomembranes on erythematous mucosa

yeast cells and pseudohyphae invade mucosal cells

(2) Herpes simplex
- small vesicles that evolve into typical “PUNCHED out” ulcers

eosinophilic intranuclear inclusions (cowdry type A) in multinuclear squamous cells at margins of ulcer

(3) CMV
- LINEAR ulceration

both intranuclear and cytoplasmic inclusions

77
Q

babesia infection

A

tick bite. endemic in northeast US.

influenza-like symptoms, hepatosplenomegaly, anemia.

often in asplenic patients

78
Q

isospora belli

A

profuse, watery diarrhea in HIV patients.

also cryptosporidium spp.

79
Q

chronic trypanosoma cruzi infection

A

Chagas disease.

dilated cardiomyopathy, achalasia & megaesophagus, megaolon, megaureter

80
Q

esophageal involvement of scleroderma (2)

A
  1. abnormal peristalsis (dysphagia)

2. lower LES tone (GERD)

81
Q

janeway lesions: painful or not?

osler nodes: painful or not?

A

janeway: NOT PAINFUL
osler: PAINFUL. osler = ouch!

82
Q

janeway lesions

A

small erythematous, possibly hemorrhagic macules that appear on soles of feet and palms in pt w. bacterial endocarditis.

caused by septic microemboli to cutaneous vasculature.

emboli = infected intracardiac vegetations (bacteria, neutrophil, necrotic materia)

83
Q

osler nodes

A

painful papulopustules on pulps of fingers and toes.

84
Q

cycloserine

A

inhibits incorporation of D-alanine into UDP-MUrNAc-oligopeptide during bacterial cell wall synthesis.

HIGH level of ototoxicity, rarely used

85
Q

polymixin

A

binds to, disrupts, and interferes w/ permeability of cytoplasmic membrane

86
Q

cysteinuria

A

autosomal recessive. only issue is stones

defective PCT and intestinal (jejunal) reabsorption of dibasic amino acid.

cysteine, ornithine, lysine, and arginine.

risk for cysteine stones –> hexagonal.

87
Q

diphenhydramine on sleep

A

H1 receptor inhibitor.

reduce time to sleep onset & increase depth of sleep.

88
Q

benzodiazepine 3 effects

A
  1. anxiolytic
  2. muscle relaxant
  3. anticonvulsant
89
Q

dystonia

A

neurological movt disorder

sustained involuntary muscle contractions. force certain parts of body into abnormal, painful movements or postures.

may affect single muscle or group.

(i.e. writer’s cramp, spasmodic torticollis, blepharospasm)

90
Q

spasmodic torticollis

A

cervical dystonia. most common focal dystonia

91
Q

blepharospasm

A

second most common focal dystonia.

involuntary, forcible closure of eyelids.

initial symptom is uncontrollable blinding.
later -> complete closure of eyelids

92
Q

myoclonus

A

sudden, brief, severe muscle contraction

93
Q

physiologic myoclonus

A

hiccups and hypnic jerks (occurs when falling asleep)

94
Q

chorea

A

involuntary muscle activity that flows from one muscle group to another. may appear fragmented or jerky. may display dancing gait.

95
Q

hemiballism

A

flinging of limbs on one side of body. due to contralateral injury of STN.

96
Q

essential tremor (postural) vs. resting tremor vs. intention tremor

A

essential: action, exacerbated by holding position (genetic predisposition)
resting: uncontrolled movement, alleviated by intentional movement (parkinsons)
intention: zig-zag motion when pointing/extending to target (cerebellar dysfunction)

97
Q

rx for essential tremor

A

b-blocker and primadone (anticonvulsant that becomes phenobarb and PEMA)

98
Q

progressive EKG findings of acute MI

A
  1. peaked T waves –> local hyperkalemia
  2. ST-segment elevation (min-hrs)
  3. Q waves (hr-days)
99
Q

transmural infarct usu caused by..

A

acute plaque change (rupture) w/ superimposed thrombus that completely occludes involved coronary artery

100
Q

stable angina begins w/ how much occlusion

A

75% occlusion

101
Q

ulcerated atherosclerotic plaque w/ partially obstructive thrombus

A

unstable angina, subendocardial MI, sudden cardiac death

102
Q

rx for early ectopic pregnancy (<6 wks)

A

methotrexate, will accumulate in rapidly dividing trophoblasts

103
Q

THF is important for what 3 general processes

A
  1. thymidine synthesis (DNA)
  2. amino acid synth
  3. purine synthesis
104
Q

folinic acid is..

A

N5-formyl-THF

N5-N10 methyelene THF

105
Q

DHF is important for which 2 rxns?

A

folic acid -> DHF

DHF -> THF

106
Q

mechanism of methotrexate

A

structually similar to folic acid. enters cell, converted to polyglutamate form.

polyglutamate form prevents movt of MTX out of cell.

(folate & DHF are stored in cells this way too)

107
Q

how is folate and DHF stored in cells?

A

polyglutamation

108
Q

PABA

A

folic acid precursor in prokaryotes. sulfonamide antibiotics are chemical analogues.

humans can’t convert PABA into folic acid. so we gotta eat folate

109
Q

folinic acid (leucovorin)

A

pre-reduced form of folic acid that can be used for synthesis of purine & thymidylate without first being converted by DHF reductase.

rescue therapy w/ MTX

110
Q

hep B mediated HCC?

hep C mediated HCC?

A
hep B:
integration into host genome: 
-inflammation
-HBx protein disrupts hepatic cell growth &
-blocks p53

hep C:
does NOT integrate
- chronic inflammation etc.

111
Q

familial hypercholesterolemia

A

autosomal DOMINANT mutation in LDL receptor

- can’t take up LDL into liver.

112
Q

serotonin syndrome drugs

A

sinners ONLY sell LACED drugs that truly make me trip &&..

TRAMADOL, ONDANSETRON (5-HT3 antagonist), LINEZOLID

st. john's wort
ondasetron
selective 5-HT reuptake (inhibitors (SSRI & SNRI)
linezolid
dextromethorphan
TCA
tramadol
MAOi
meperidine
triptans
113
Q

serotonin syndrome presentation (3)

A

(1) neuromuscular excitation: hyperreflexia, clonus, myoclonus, rigidity
(2) autonomic stimulation: hyperthermia, tachycardia, diaphoresis, tremor
(3) altered mental status: agitation & confusion

114
Q

rx for serotonin syndrome

A

cryptoheptadine 5-HT2 receptor antagonist

115
Q

linezolid

A

serious gram positive infections (VRE and MRSA). weak monoamine oxidase inhibitor. can ppt serotonin syndrome

116
Q

doxycycline toxicity

A

photosensitivty, pill induced esophagitis.

enamel hypoplasia or permanent tooth discoloration

117
Q

which commonly used drugs can ppt serotonin syndrome in a patient using SSRIs etc?

A

tramadol, ondansterone, and linezolid

118
Q

propanonol helps hyperthyroidism by.. (2)

A

(1) reduce symptoms (thyroid hormone upregulate b-adrenergic expression)
(2) reduce peripheral conversion of T4 to T3

119
Q

3 drugs that block peripheral conversion of T4 -> T3?

A

(1) PTU
(2) ipodate
(3) b-blockers

120
Q

which hormone upregulates beta-receptor expression? alpha-receptor?

A

beta-receptor: thyroid hormone (increase HR, anxiety)

alpha-receptor: cortisol (increase BP)

121
Q

which hyperthyroid symptoms are NOT improved by beta-blockers?

A
  • increased tissue oxygen consumption
  • circulating thyroxine levels
  • weight loss
  • exopthalmosis (graves)

helps w/ HR and anxiety!

122
Q

crystals in gout?

A

monosodium uraate

123
Q

where can monosodium urate crystals deposit?

A

(1) joint

(2) tissue -> tophi nodules

124
Q

describe gouty arthritis

A

monosodium urate ppts in joint, eaten by neutrophils –> inflammatory response

125
Q

typical gout patient and presentation

A
  • 40-60 y/o obese patient.
  • MONOarticular (podagra, usu MTP)
  • acute onset joint pain, warmth, erythema, swelling

will resolve w/o treatment

126
Q

definitive diagnosis of gout?

A

synovial fluid analysis: increased WBC, mostly NEUTROPHILS.

micropscoy: monosodium urate crystals: parallel -> yellow, negatively birefrigent under polarized light.

127
Q

negative birefringence means..

A

aligned parallel to ray -> yellow

aligned perpendicular -> blue

128
Q

uric acid into joint?

A

does NOT cause gout. need monosodium urate crystals, not just uric acid.

129
Q

pseudogout?

A

clinically just like gout.

joint: see rhomboid blue crystals of calcium pyrrophosphate.

affects both genders. larger joints.

130
Q

calcific tendonitis

A

deposits of calcium hydroxyapatite crystals in periarticular soft tissue (esp tendon)

usu rotator cuff

131
Q

what deposits in joints during gout?

A

monosodium urate.

NOT uric acid.

132
Q

organs primarily affected in hemochromatosis (4)

A

liver, heart, and pancreas

& skin

133
Q

hemachromatosis inheritance

A

autosomal recessive

134
Q

budd-chiari

A

syndrome secondary to thrombotic occlusion of hepatic vein OR intra/suprahepatic IVC

increased sinusoidal pressure –> portal HTN, ascites, hepatomegaly, splenomegaly

135
Q

patient younger than 30 y/o with unexplained chronic hepatitis?

A

consider WILSON’s disease.

low ceruloplasmin, increase urinary Cu2+ excretion, Kayser-Fleischer rings

136
Q

rapid correction of hyponatremia can cause..

A

low to high, pons will die
osmotic demyelination.
central pontine myelinolysis

locked-in syndrome:

  1. spastic quadriplegia: demyelination of corticospinal tracts
  2. pseudobulbar palsy: demyelination of corticobulbar tracts of CN IX, X and XI
137
Q

pseudobulbar palsy is..

bulbar palsy?

A

head & neck muscle weakness, dysphagia, dysarthria.

pseudobulbar = NUCLEI of corresponding cranial n. IN TACT.

bulbar palsy = pathologic process in nuclei of these tracts

138
Q

rapid correction of hypernatremia can cause

A

cerebral edema

139
Q

magnesium citrate & polyethylene glycol are..

A

osmotic laxatives – distend intestinal wall and increase peristalisis

140
Q

rectal prolapse

A

protrustion of rectal mucosa through anus

associated w/ pregnancy & constipation & severe diarrhea & cystic fibrosis

141
Q

composition of keratin (3)

A

(1) alanine & (2) glycine
small, tightly coil, many H bonds

& (3) cysteine
disulfide allows for rigidity

142
Q

vimentin is a marker for

A

mesenchymal cells – intermediate filament

143
Q

RNA pol I makes

A

18S, 5.8S, 28S rRNA
(from single: 45S pre-RNA gene that is then cleaved)

only in nucleolus

144
Q

RNA pol II makes (3)

A
  1. mRNA
  2. snRNA (small nuclear: mRNA splicing and transcription regulatoin
  3. miRNA (micro: silencing via translation arrest / mRNA degradation
145
Q

RNA pol III makes (2)

A
  1. tRNA

2. 5S rRNA (essential component of 60s ribosomal subunit)

146
Q

production of rRNA

A

45s pre-rRNA genes divided among multiple chromosomes.

arranged into clusters called “nucleolar organizing regions” –> such that all copies are located in nucleolus

147
Q

role of nucleolus

A
  • transcribe rRNA
  • maturation & assembly of ribosomal subunits

(ribosomal protein componenets are made in cytoplasm and brought into nucleolus).

complete ribosome is shuttled out of nucleus.

148
Q

5s rRNA is special bc

A

only rRNA located outside of nucleolus (made by RNA Pol III)

149
Q

classic signs of mononucleosis

A

sore throat
moderate - high fever
cervical lymphadenopathy
splenomegaly

150
Q

h. pylori associated w/ what malignancies

A

gastric adenocarcinoma

MALToma