test #47 5.6 Flashcards Preview

UWorld mixed > test #47 5.6 > Flashcards

Flashcards in test #47 5.6 Deck (108)
Loading flashcards...
1
Q

POMC is a polypeptide cleaved to make..

A

ACTH
MSH
enkephalins

2
Q

enkephalins, endorphins, dynorphins all bind to

A

endogenous opoids

bind to mu, delta, fatta receptors

3
Q

somatomedin C

A

= IGF-1

released in response to growth hormone

4
Q

middle meningeal artery is a brach of..

A

maxillary artery, which is a branch of the external carotid artery

epidural hematoma

5
Q

occipital artery

A

branch of external carotid

supply posterior scalp & SCM

6
Q

opthalmic artery

A

branch of internal carotid:
serves eye & orbit contents

also eyelid, forehead, nose, nasal mucosa

(internal carotid has no branch in neck)

7
Q

artery responsible for nosebleeds

A

kiesselbach’s plexus,

sphenopalatine artery (branch of maxillary artery) anastamoses w/ opthalmic & facial

8
Q

facial artery

A

branch of external carotid
couses over mandible anterior to insertion of masseter

supply oral region & nose & buccal

9
Q

how does middle mengingeal artery enter skull

A

foramen spinosum

10
Q

touch to anterior 2/3 of tongue

A

trigeminal V3

lingual n

11
Q

touch to posterior 1/3 of tongue

A

glossopharyngeal CN IX

12
Q

intrinsic muscles of tongue innervated by (2)

A

most: CN XII hypoglossal

palatoglossus -> CN X vagus

13
Q

taste in pharynx & epiglottis

A

vagus CN X

14
Q

ESR increased due to

A

acute phase reactants released by IL-6

fibrinogen, ferritin, CRP, serum amyloid A, serum amyloid P, complement

15
Q

why does erythroyte sedimentation increase w/ inflammation

A

fibrinogen causes RBC to rouleaux –> sediment faster

16
Q

cytokines impt for systemic inflammation (3)

A

IL-1, IL-6, TNF-alpha

17
Q

bradykinin effects (4)

A

vasodilation
vascular permeability
smooth muscle contraction
pain

18
Q

PAF effects

A

vasoconstriction
bronchoconstriction
platelet stimulation

also enhances leukocyte adhesion to endothelium, chemotaxis, phagocytosis, degranulation

19
Q

epinephrine for anaphylactic shock

A

counteracts the..
1. vasodilation
by alpha-1 agonist vasoconstrction

  1. increased vascular permeability
    by increases CO, B1 agonist
  2. bronchoconstriction
    by bronchodilating, B2 agonist
20
Q

morphology of crytococcos neoformans

A

yeast only
round/oval encapsulated w/ narrow based buds

virulence: thick polysacch capsule

21
Q

flutamide, cyproterone

A

blocks androgen receptor

testosterone/DHT

22
Q

leuprolide, goserelin, nafarelin, histrelin

A

GnRH agonists

23
Q

anorexia induced amenorrhea due to..

A

hypothalamic dysfunction

nonpulsatile GnRH

(NOT problem in pituitary/gonad)

24
Q

most important mediator of sepsis

A

TNF-alpha

also IL-1, IL-6

25
Q

liver cyst in person from endemic region (middle easy, south america, iceland, australia, new zealand, africa) or sheep/dog exposure

A

echinococcus granulosus

encapsulated calcified cyst

rupture: eosinophilia –> ANAPHYLAXIS
rx: bendazole

26
Q

mitral stenosis can cause hoarseness bc..

A

compression of left recurrent laryngeal

via really enlarged left atrium

27
Q

recurrent laryngeal innervates

A

all intrinsic muscles of larynx except cricothyroid

28
Q

p-ANCA suggests..

A

microscopic polyangiitis

or churg-strauss (eosinophilia)

29
Q

characterize churg strauss

A
adult onset asthma
eosinophilia
history of allergy
mono or poly-neuropathy
migratory/transient pulmonary infiltrate
paranasal sinus abnormalities
30
Q

mechanism of glucose-induced inhibition of lac operon

A

glucose decreases adenylyl cyclase, depleting cAMP

REDUCTION of cAMP, low CAP-DNA binding

(not related to repressor binding to operon)

31
Q

operon

A

DNA sequence that has at least 2 regulatory sites: promoter & regulator (operon) in addition to gene coding for protein

32
Q

lac operon

A

proteins required for metabolism of lactose

regulatory gene,
- repressor for lac operon

promoter gene,
- binding site for RNA pol

operator gene
- binding site for repressor

3 structural gene

  • b-gal
  • permease

low cAMP, (caused by glucose) shuts it off

33
Q

culturing e. coli in lactose. what happens in lac operon

A

lactose (inducer) binds to repressor protein, which can no longer bind to operon.

increases transcription of lac operon.

34
Q

anti-reticulin, anti-endomysial antibodies

A

along w/ anti-gliadin

in celiac sprue

35
Q

urticaria (hives) histologically

A

DERMIS: mild, superficial infiltrate of mononuclear cells & eosinophils around dermal venules.

collagen bundles are parted by DERMAL EDEMA and lymphatic channels dilated w/ excess transudate

no epidermal changes

antigen induced degranulation of focal mast cells due to IgE antibody sentization

or, direct activatio nof mast cells

microvasculature hyperpermeability

36
Q

urticaria vs. eczematous dermatitis

A

urticaria (wheel): DERMAL edema

eczematous dermatitis: spongiosis (epidermal edema) w/ acantholysis

37
Q

staph aureus food posioning due to

A

exotoxin formed prior to ingestion

highly heat stable enterotoxin

rapid onset: less than 6 hrs

usu mayo containing (potato, macaroni salad)

(similar to b. cereus, but diff food)

38
Q

b. cereus food poisioning

A

similar to staph aureus!
exotoxin formed prior to ingestion

heat stable

but, diff food: here, reheated rice

39
Q

exotoxin staph aureus diseases (3)

A
  1. toxic shock
  2. scalded skin
  3. gastroenteritis
40
Q

pulsatile notching vessels under ribs

A

coarctation of aorta

could also have headache & epistaxis from HTN in blood to head – post-ductal in adults

41
Q

3 major risk factor for squamous cell carcinoma of esophagus

A

alcohol
smoking
n-nitroso-containing foods (smoked fish, etc)

(asia: chewing betel nut & n-nitroso compounds)

42
Q

3 major risk factors for adenocarcinoma

A

barrett’s esophagus
GERD
obesity
tobacco use

43
Q

anytime you see a squamous cell carcinoma

A

expect keratin pearls

44
Q

mu opiod receptor responsible for

A

respiratory & cardiac depression
reduce GI motility

also: dependence, euphoria, sedation

45
Q

kappa opiod receptor responsible for..

A

miosis

also: dysphoria, sedation

46
Q

delta opiod receptor responsible for..

A

antidepressant effects

47
Q

naloxone

A

opiod receptor antagonist, especially mu

good for overdose / intoxication rx

48
Q

terbinafine antifungals act on..

A

block squalene expoidase

prevent conversion of langosterol to ergosterol

49
Q

rx for dermatophytosis (i.e. tinea corporis)

A

terbinafines

50
Q

MRI of MS

A

periventricular plaques of demyelination (axons in tact)

51
Q

MLF damage

A

impaired adduction of eye during lateral gaze

BUT

intact adduction w/ ocular convergence

i.e. not a problem w/ nerve or muscle

52
Q

what’s inside an acute MS plaque?

A
  1. demyelination w/ preservation of axon
  2. accumulation of lipid-laden macrophages
  3. astrocytosis (response to injury)
  4. infiltration by lymphocytes / mononucear cells

overtime: damage of axons, neurons, oligodendrocytes

53
Q

hypertensive heart results in what type of dysfxn

A

DIASTOLIC

concentric hypertrophy; net decrease in LV chamber size

filling and diastolic fxn is normal though

54
Q

what causes hepatic injury w/ hepatitis B infxn

A

NOT direct cytopathic effect if virus

instead, MHC I expression of HbsAg & HbcAg activates CD8+ T cells to attack

damage tapers when HBV is incorportated into host genome & antiviral antibodies appear

risk of hepatocellular carcinoma remains elevated

55
Q

autoimmune hepatitis

A

due to antigen mimicry w/ generation of self-antigen recognizing CD4+ T lymphocytes that damage hepatocytes

56
Q

location of broca

A

inferior frontal gyrus

57
Q

MCA covers what impt territories

A

all lateral hemispheres

  • frontal eye fields
  • broca (inferior frontal gyrus)
  • wernicke (posterior superior temporal gyrus)
  • primary motor cortex esp face/hands
  • some perforating branches to internal capsule & basal ganglia
58
Q

left hemipshere is dominant (side of language) in what people

A

most left & right handed people

59
Q

ACA infarct can present w/

A

hemiplegia of lower extremities
urinary incontinence
primitive reflexes

60
Q
  1. contralateral loss of pain & temp
  2. ipsilateral deficits of CN V,
  3. ipsilateral facial CN VII
  4. ispilateral vestibulococh CN VIII
  5. horner’s
  6. cerebellar symptoms
A

AICA occlusion causeslateral inferior pontine syndrome

61
Q
contralateral loss of pain & temp
w/ 
ipsilateral defecits in CN V, VIII, IX, X, & XI
w/ 
Horner

notably: dysphagia & hoarseness

A

PICA, lateral medullary

62
Q

abdominal pain, distension
w/
fever, diarrhea, shock
in ulcerative colitis patient..

A

think: toxic megacolon

63
Q

toxic megacolon is more common in..

A

ulcerative colitis

64
Q

pathogenesis of toxic megacolon

A

complete cessation of neuromuscular activity in intestinal wall.

rapid colonic distension -> prone to rupture

segmental necrosis

perforation risk!

65
Q

diagnosis of toxic megacolon

A

sufficient w/ plain abdominal x-ray: colonic dilatation, maybe fluid levels

66
Q
  1. chora
  2. aggression/apathy/depression
  3. dementia
A

hungtington

67
Q

w/ hungtingtons, when does expansion of CAG repeats occur?

A

in spermatogenesis!

when receive abnormal gene from father, tend to have ANTICIPATION

no expansion from mama

68
Q

emotional lability
insatiable hunger & thirst
in child

A

prader-willi
mutation in chr. 15 of papa

(same gene as angelman)

69
Q

happy puppet
jerky movement (like marionette)
pathological happy disposition

A

angelman
mutation in chr. 15 of mama

(same gene as prader-willi)

70
Q

multiple myeloma

A

neoplastic B-lymphocytes mature into plasma cells that synthesize abnormally large amounts of monogclonal Ig or Ig fragments (light chains)

  • impaired hematopoesis (bc bone marrow filled w/ plasma cells)
  • lytic bone lesions
  • hypercalcemia
  • AL amyloidosis
  • renal dysfxn
71
Q

lab abnormalities in multiple myeloma

A

rouleaxu erytheocytes in blood

bence jones protein in urine

M peak on serum protein electrophoresis – monoclonal proliferation

72
Q

prognosis for esophageal cancer

A

generally poor, present w/ incurable locally advanced or metastatic disease

73
Q

histology of reflux esophagitis (3)

A

elongation of papillae
basal cell hypertrophy
intraepithlieal EOSINOPHILS

usu leads to barett esophagus

74
Q

benign tumor of esophagus

A

super rare, but could be leiomyoma

75
Q

why do colonic diverticula form? describe mechanism & fate

A

mechanism: pulsion
structure: false

mucosa & submucosa herneat through weak spots in colonic muscular layer; due to increased intraluminal pressure (i.e. constipation)

76
Q

false diverticula (2)

A

colonic & zenker in upper esophagus

77
Q

presentation of colonic diverticula

A

lower GI bleed

78
Q

traction diverticula

A

inflammation & scarring.
true: contains 3 layers

example: midesophageal diverticula, which occur w/ mediastinal lymphadenitis and periesophageal scarring

79
Q

location & predisposition for colonic diverticula

A

usu sigmoid colon

constipation : risk factor

80
Q

lack of peroxisomes prevents

A

special form of beta oxidation for
very long chain fatty acids

or alpha oxidation for branched chain fatty acids (phytanic acid)

accumulate fatty acids in tissue

81
Q

Zellweger syndrome

A

absence of peroxisomes

infant unable to make myelin in CNS

present: hypotonia, seizures, hepatomegaly, metal retardation, early death

82
Q

Refsum disease

A

defective alpha oxidation in peroxisomes

leads to neuro disturbances bc accumulate phytanic acid

rx; avoid chlorophyll in diet

83
Q

what types of fatty acids does the mitochondria NOT oxidize

A

very long chain fatty acids

or

fatty acids w/ branch points at odd number carbons

(peroxisome does)

84
Q

rx for NARDs

A

supplemental oxygen at high concentration

nasal continuous positive airway pressure

mechanical ventilation w/ intratracheal surfactant

85
Q

concern w/ oxygen therapy in neonate

A

retinal damage

local hyperoxia –> upregulate VEGF –> retinal detachment/blindness

retinopathy or prematurity
or
retrolental fibroplasia

86
Q

causes of acute MR

A

spontaneous rupture of chordae tendinae, infective endocarditis w/ destruction of valve leaflets, chordal rupture, ischemia /rupture of papillary muscles

87
Q

compliance =

A

V/P

88
Q

left atrial compliance in acute MR? chronic?

A

acute: normal compliance, so will lead to pulmonary edema
chronic: increased compliance, less prone to pulmonary edema, but more protein to Afib & thromboemboli

89
Q

thiamine deficiency on TCA cycle

A

most severely impairs alpha-ketoglutarate dehydrogenase –> succinylCoA

dehydrogenases require thiamine, lipoate, CoA, FAD, NAD+

90
Q

thiamine, lipoate, CoA, FAD, NAD+ are important for..

A

alpha ketoglutarate dehydrogenase

pyruvate dehydrogenase

acyl-CoA dehydrogenase

91
Q

thiamine needed for

A

transketolase (specific)

alpha ketoglutarate dehydrogenase

pyruvate dehydrogenase

acyl-CoA dehydrogenase

92
Q

rate limting step in TCA

A

isocitrate dehydrogenase

isocitrate -> alpha-ketoglutarate

first NADH produced

93
Q

what step of TCA makes GTP

A

succinyl CoA -> succinate

succinylCoA synthetase

substrate level phosphorylation

94
Q

what step of TCA makes FADH

A

succinate dehydrogenase

succinate -> fumarate

95
Q

order things are made in TCA

A

starting w/ isocitrate -> alphaketo

NADH (isocitrate -> alpha-keto)
NADH (alphaketo -> succinylcoa)
GTP (succinylcoA -> succinate)
FADH (succinate -> fumarate)
skip (fumarate -> malate)
NADH (malate -> oxaloacetate)
96
Q

alcohol dehydrogenase & acetaldehyde dehydrogenase both

A

increase NADH/NAD+ ratio

though all of TCA is inhibited w/ alcohol, thiamine dependent ones are especially inhibited

97
Q

mifepristone RU-486

A

anti-progestin
abortifacient

decidual necrosis and expulsion of products of conception

98
Q

misoprostol

A

prostaglandin analogue, also abortifacent

also increases gastric mucosal barrier

99
Q

methotrexate on pregnancy

A

inhibits trophoblast division

used for ectopic pregnancy

100
Q

common complication after subarachnoid hemorrhage

A

secondary arterial vasospasm

can lead to cerebral ischemia

present: new onset confusion / focal neuro defect 4-12 days after initial insult

can also have rebleed: see on CT

101
Q

rx to prevent vasospasm after a subarachnoid hemorrhage

A

nimodipine, selective Ca2+ channel blocker

102
Q

linear velocity V =

A

Q/A

or total flow = velocity x cross sectional area; where flow = constant

103
Q

addition of what in a pt w/ hemophilia will induce clotting

A

thrombin! will then activate fibrinogen -> fibrin

104
Q

fatal toxicity w/ digoxin

A

arrthythmia due to hyperkalemia

105
Q

associated NF-1 findings

A

meningioma, astrocytoma, glioma, pheochromocytoma

106
Q

inheritance of NF-1

A

single gene autosomal dominant

107
Q

how is INH neurotoxic?

A

chemically similar to vitamin B6, can compete with it in synthesis of ntx (GABA) resulting in defective end products

also increases urinary excretion of pyridoxine

neurotoxic bc causes VITAMIN DEFICIENCY

drug is not directly toxic!

108
Q

counteract isoniazid toxicity

A

supplement w/ B6

neurotoxicity due to vitamin deficiency!