test #31 4.20 Flashcards Preview

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1
Q

posteroinferior wall of left ventricle supplied by.. infarct on ECG?

A

posterior descending branch of RCA.

ST elevations in leads II, III, aVF

2
Q

transmural ischemia of interventricular septum on EKG?

A

ST elevation in leads V1 V2

3
Q

transmural ischemia of anterior left ventricular wall on EKG?

A

ST elevation in V3 V4

4
Q

occlusion of proximal LAD infarcts.. causes on EKG?

A

infarts anteroseptal transmural ischemia. ST elevations in V1-V4

5
Q

anterolateral infarct of left ventricle on EKG?

A

LCX or LAD – V4-V6

6
Q

lateral wall of left ventricle infarct on EKG?

A

I, aVL & V5-V6

7
Q

which segment of intestine is always involve w/ hirschsprung? why?

A

rectum, bc ganglion cells of submucosa & myenteric plexi travels caudally.

aganglionic segment -> constricted bc cannot relax

8
Q

torsades

A

form of ventricular tachycardia.

polymorphic QRS complexes of varying amplitudes and cycle length.

give appearance that the tip of QRS is twisting around ECG baseline.

always associated w/ underlying prolonged QT

9
Q

prolonged QT caused by..

A

class IA and III antiarrhythmics
(not amiodarone)
phenothiazines
TCAs

10
Q

lidocaine fxn by..

A

blocking Na+ channels

11
Q

penicillins are structurally stimilar to

A

terminal d-ala-d-ala of peptidoglycan molecule

blocks transpeptidase

12
Q

N-acetylmuramic acid and N-acetylglucosamine are

A

peptidoglycan precursor molesules of cell wall in bacteria

13
Q

sulfonamide antibiotic mechanism? trimethoprim

A

sulfonamides: compete w/ PABA (paraaminobenzoic acid) for incorporation into folic acid..
trimethoprim: block dihydrofolate reductase

14
Q

staph epidermidis infxn?

rx:

A

major cause of infection in pts w/ indwelling catheters or implanted foreign bodies.

produces biofilm (polysaccharide slime) allows adhesion.

diagnosis: recover from mult cultures (can be contaminant)
rx: initial aggressive. vancomycin w/ rifampin or gentamycin or both.

can be resistant to methicillin

15
Q

rx for staph epidermidis bactermia. if not..?

A

aggressive! vancomycin + rifampin + gentamycin

w/o rx: indolent endocarditis after valve replacement. intracardiac abscess formation, dehiscence of prosthetic valve, septic embolization

16
Q

AML blasts will stain positive for

A

peroxidase (since Aur rods have MPO)

17
Q

TdT in lymphocytes

A

terminal deoxynucleotidyl tranferase

add nucleotides to V D J regions of Ab gene for diversity.

mature of immature B and T cells

18
Q

hairy cell leukemia stains. what type of cells are they?

A

TRAP (tartare resistant acid phosphatase)

B-cells! CD20+

splenomegaly, fatigue, pancytopenia

19
Q

glomus body & glomus tumor

A

small, encapsulated neurovascular organ. temp regulation

in dermis of nail bed, pads of fingers & toes, ears

afferent arteriole –> richly innervated, muscular arteriovenous anastomosis –> efferent vein.

role:

COLD: shunt blood AWAY from skin surface: prevent heat loss
HEAT: direct blood TO skin, facilitate dissipation of heat.

form PAINFUL tumors under fingernail. arises from modified smooth muscle cells.

20
Q

skin presentation of histiocytosis

A

erythematous papules, nodules, and/or scaling plaques

21
Q

electrolyte presentation of primary adrenal insufficiency (Na, K, Cl, HCO3)

A

low Na
high K
low Cl
low HCO3

22
Q

primary adrenal insufficiency vs. secondary / tertiary (i.e. pituitary / hypothal)

A

primary – loose aldosterone, cortisol, and androgens

secondary – loose cortisol only. aldosterone triggered by renin / angiotensin system!

23
Q

Na+ in hyperaldosterone?

A

initial increase, but aldosterone loss –> intravascular hypervolemia –> ANP –> diuresis & compensatory Na+ loss

24
Q

why is supraspinatus injury most common of rotator cuff?

A

repeated impingement trauma between humeral head & acromion

abbductor

25
Q

subacromial bursa location

A

under both acromion/clavicle & tendon of deltoid muscle.

sits on top of supraspinatus

26
Q

why no hep C vaccine // why prone to chronic infection

A

variety in antigenic structure of HCV envelope proteins

  1. multiple genotypes & subgenotypes
  2. hypervariable region of envelope glycoprotein – prone to frequent mutation
  3. no proofreading 3-5’ exonuclease

constantly emerging mutant strains &much variety in a single person at one time

27
Q

positive trendelenburg sign

A

hip dips to unaffected side when standing on affected sign (failure of gluteus medius/minimus to pull pelvis down and abduct thigh) –> superior gluteal n.

28
Q

sciatic n. innervates all knee flexors except..

A

biceps femoris

29
Q

Tzanck prep

A

Wright-Giemsa stain on epithelial cells scraped from ulcer base.

see multinucleated giant cells w/ some intranuclear inclusions – HSV & VZV

30
Q

primary vs. reactivation HSV-1 infxn

A

recurrent:
- usu one side
- much less extensive area involved (limited)
- favor skin around mucosal orifice (lips & nose)

  • bilateral
  • larger area
  • gingivostomatitis: gums & oral mucosa
31
Q

primary vs. reactivation of VZV infxn

A

reactivation won’t cross midline either

32
Q

latency means..

A

full viral genome persists in host cells, but infectious virons cannot be recovered from those cells that harbour the virus.

33
Q

slow virus infection

A

prolonged incubation period, months to years. virus persistently infects host & multiplies before gradually causes clinically apparent disease.

predominantly progressive, degenerative disorder of CNS – SSPE, PML

34
Q

S3 sound

A

early in diastole. sudden deceleration of entering blood column as ventricle reaches its elastic limit

reverberation of blood between ventricle walls. low frequency

  1. forceful, rapid filling of a ventricle w/ normal or elevated compliance
  2. normal, or even decreased filling rates when compliance is low
  3. blood flowing into an overfilled ventricle w/ high end-systolic volume
35
Q

murmur associated w/ HCM

A

dynamic LVOT – mitral regurgitation – systolic. or ‘aortic stenosis’ like??

36
Q

pattern of drug administration for nitrates?

A

nitrate free interval every day. rapid tolerance

due to decreased vascular sensitivity & increased sensitivity to vasoconstriction

37
Q

MAO inhibitors (phenelzine) fxn by..

A

IRREVERSIBLY bind. takes 2 wks post discontinuation to regenerate enzyme

wait before giving SSRI

38
Q

SSRI + MAOi =

A

serotonin syndrome. wait 2 wks after discontinuing MAOi before giving SSRI

39
Q

drug of choice for paroxysmal supraventricular tachycardia?

A

adenosine – open K+ channels, hyperpolarize AV node.

acts in manner similar to muscarinic cholinergics

40
Q

side effects of adenosine for PSVT?

A

flushing, chest burning (bronchospasm), hypotension, high grade AV block

41
Q

side effects of amiodarone

A

blue-grey skin discoloration, photodermatitis, pulmonary fibrosis, hypo/hyperthyroidism

42
Q

lidocaine side effects/toxicity

A

neurologic symptoms usu

43
Q

procainamide toxicity

A

usu drug-induced lupus syndrome

44
Q

verapamil side effects

A

gingival hyperplasia and constipation

45
Q

digoxin/digitalis side effects / toxicity

A

fatigue, blurry vision, changes in colour perception, nausea & vomiting, diarrhea, abdominal pain, confusion, delirium

46
Q

drug used for chemical stress test?

A

adenosine! causes bronchospasm, flushing, high grade block!

47
Q

vomit pathway

A

proprionylCoA –> methymalonylCoA
(propionylCoA carboxylase + biotin)

methylmalonylCoA –> succinylCoA
methylmalonylCoA mutase

48
Q

malonyl CoA comes from..

A

acetylCoA + acetylCoA carboxylase

49
Q

methylmalonyl CoA comes from..

A

propionylCoA + propionylCoA carboxylase

50
Q

hydrolysis in urea cycle

A

arginine to ornithine via arginase

51
Q

transamination

A

converts alpha-ketoacids to amino acids (via transfer of amino group from one amino acid to alpha-keto acid)

usu requires B6

52
Q

methylmalonic acidemia

A

defet in isomerization rxn. transforms methylmalonyl CoA to succinyl COA – TCA

53
Q

parvovirus infxn in adult:

A

arthritis involving proximal interphalangeal, metacarpal knee, and ankle

usu symmetric (like RA) but spontaneously resolves (unlike RA)

54
Q

hyaline membranes in ARDS

A

alveolocapillary membrane leakage. fibrin exudate and plasma protein-rich edema fluid mixed w/ cytoplasmic and lipid remnants of necrotic epithelial cells.

exudate-like. not transudate.

55
Q

smell is from..

A

apocrine glands

56
Q

apocrine glands

A

dermis / subcutaneous fat of breast areolae, axillae, genital.

membrane bound vesicles “sweat” into hair follicles. rather than directly to skin.

innervated by adrenergic fibers of sympathetic nervous system. not fxn until puberty.

women – cyclical changes secondary to hormonal influence w/ menstrual cycle.

usu odorless when secreted. malodorous secondary to activity of commensal bacteria in skin.

57
Q

holocrine glands

A

associated w/ SEBACEOUS glands. discharge of entire cell undergo breakdown to release secretory product & meibomian glands in eye

58
Q

eccrine (merocrine)

A

skin throughout body. except lips and glans penis.

merocrine glands secret watery fluid rich in Na and Cl “sweat” directly to skin

59
Q

mammary glands (lactation)

A

modified sweat glands. apocrine secretion.

60
Q

aldosterone functions by..

A

binding to intracellular receptor and altering gene expression

(1) more Na/K pumps
(2) ENaC on principal cells
(3) increase K+ secretion from principal cells
(4) increase H+ secretion from intercalated cells

61
Q

which chemical increases urea transport in collecting ducts

A

ADH

62
Q

inheritance of phenylketonuria?

A

autosomal recessive. mental retardation, eczema, mousy musty body odor

63
Q

ritodrine and terbutaline

A

b2 agonist. tocolysis. relaxes uterus. defer premature labor

64
Q

inheritance of glucose 6 phosphate dehydrogenase

A

x-linked recessive

65
Q

MOST structural abnormalities are inherited as..

A
autosomal dominant
(i.e. hereditary spherocytosis)
66
Q

MOST enzyme deficiencies inherited as..

A

autosomal recessive

67
Q

X-linked dominant? example

A

100% risk to female offspring of an affected male.

vitamin-D-resistant rickets

68
Q

when does mismatch repair (i.e. that mutated in lynch: MSH2 and MLH1) function

A

shortly after daughter strands synthesized.

69
Q

DNA deaminating agents. repair?

A

nitrous acid.

base pair excision repair: glycosylase detect, create an empty sugar-phosphate residue (apurinic site)

70
Q

how does alcohol cause pancreatitis

A

induces pancreatic secretions w/ high protein concentration and low fluid content – prone to ppt.

also causes spasm of sphincter of Oddi – direct toxic effect on acinar cells

71
Q

main causes of acute pancreatitis (2)

A
  1. gallstones

2. alcohol abuse!

72
Q

alcohol abuse leads to what hematological abnormality

A

macrocytosis (MCV) secondary to…

(1) poor nutrition: folate / b12
(2) direct toxicity of alcohol on bone marrow

73
Q

3 indicators of chronic alcohol abuse

A

(1) macrocytosis (RBC)
(2) AST:ALT ratio > 2
(3) elevated gamma-glutamyltransferase (GGT)

macrocytosis can occur independently of folate or cobalamin deficiency

74
Q

chediak-higashi

A

phagocyte dysfunction:
BALIN
autosomal recessive

defect in LYST – lysosomal regulator gene. MT dysfunction in phagolysome-lysosome function.

  • bleeding and bruising (platelet deficiency)
  • albinism (partial oculocutaneous albinism)
  • leukopenia
  • infxn w/ staph strep peripheral
  • neuropathy
75
Q

wiskot aldrich

A

B and T cel disorder
mutation in WAS
X-linked recessive

T cells unable to reorganize actin.
B cells can’t anchor membrane bound receptors well

WATER

wiskot-aldrich
thrombocytopenic purpura
eczema
recurrent infection

low to normal IgG and IgM
high IgE and IgA
fewer and smaller platelets

increased risk of non-hodgkin’s lymphoma

76
Q

immunodeficiency with partial oculocutaneous albinism and neurological defects (i.e. nystagmus)

A

chediak-higashi (defective neutrophil phagolysosome function)

77
Q

side effects of lithium

A

LMNOP

lithium
movement (tremor)
nephrogenic diabetes insipidus
hypOthyroidism
pregnancy -- ebstein's anomaly

monitor BUN/creatinine and TSH

78
Q

clozapine atypical antipsychotic can cause

A

agranulocytosis & seizures

79
Q

risperidone can cause..

A

increase prolactin.

galactorrhea and amenorrhea

80
Q

trazodone side effects

A

painful erection (priapism), orthostatic hypotension, sedaition

81
Q

olanzipine/clozapine side effect

A

weight gain

82
Q

ziprasidone side effect

A

prolong QT

83
Q

atypical antipsychotic with least side effect

A

aripripazole

84
Q

presentation of polycythemia vera

A

plethoric face, splenomegaly.

increase incidence of..

  1. peptic ulcerative (altered blood viscosity)
  2. itching (histamine release from basophils)
  3. gouty arthritis (increased cell turnover)
85
Q

examples of JAK STAT signalling

A

ERO

86
Q

describe JAK STAT signalling

A

nonreceptor tyrosine kinase.

ligand binds –> JAK comes and phosphorylates. attracts STAT, which is phosphorylated –> then goes to nucleus for effect

87
Q

examples of RTK activity

A

insulin, IGF-1, EGF

88
Q

li-fraumeni syndrome associated w/ which cancers

A
  • sarcomas and tumor of breast
  • brain
  • adrenal cortex
89
Q

photosensitivty in porphyria due to

A

formation of porphyrin-mediated superoxide free radicals from oxygen upon sunlight exposure

90
Q

where does H. pylori like living in the stomach?

A

antrum: in prepyloric area, where there are few acid-secretory parietal cells.

will cause gastric metaplasia of duodenum (due to increased acid secretion), and will THEN colonize duodenum

91
Q

where can H. pylori live?

A

ONLY in areas of gastric metaplasia!

can’t live in normal duodenum

92
Q

myocardial biopsy with interstitial collection of mononuclear inflammatory cells * scattered multinucleated giant cells, surrounded by fibrosis?

A

interstitial myocardial granulomas: aschoff bodies)

acute rheumatic carditis.

plump macrophages w/ abundant cytoplasm & central, round-to-ovoid nuclei w/ central, slender, chromatin ribbons – Anitschkow cells “caterpillar”.

Aschoff giant cells: when larger macrophages become multinucleated.

can be found in any 3 layers of heart. later replaced by fibrous scar tissue.

preceeded by episode of group A strep 10 days to 6 wks earlier

93
Q

predominantly lymphocytic interstitial inflammatory infiltrate w/ focal necrosis of myocytes adjacent to inflammatory cells

A

viral myocarditis

94
Q

interstitial inflammatory infiltrate of mononuclear inflammatory cells & eosinophils in heart

A

hypersensitivty myocarditis

95
Q

diptheric myocarditis

A

circualting toxin produced by primary focus of infxn in upper aerodigestive tract (tonsilopharyngitis)

pleomorphic interstitial infiltrate of macrophages w/o distinct Ascoff-body type granulomas

96
Q

distension of individual myofibers w/ intracellular trypanosomes in heart?

A

chagas disease, trypanosoma cruzi

97
Q

most common cause of end state renal failure in US

A

diabetic nephropathy

98
Q

kidney disease w/ hyperuricemia?

A

monosodium urate crystal ppt in medullary interstitium –> fibrosis and foreign-body granulomas (gouty nephropathy).

can result in chronic renal failure.

microscopically – negatively birefringent under polarized light

99
Q

psychogenic erectile dysfunction

A

usually sudden & have spontaneous morning erections (integrity of neurologic / vascular disease)

100
Q

what sexual features decrease w/ age

A

longer refractory period, take longer to achieve erection

sexual desire does not fall

101
Q

most common mediations causing impotence

A

SSRI and sympathetic blockers (clonidine, methyldopa, beta blockers)

102
Q

signs of irreversible injury in heart

A

mitochondrial vaculolization

appearance of vaculoes and phospholipid-containing amorphous densities WITHIN mitochondria

implies permanent inability to generate ATP via oxidative phosphorylation.

[simple mito swelling = reversible]

103
Q

myofibril relaxation results from..

A

reversible injury:
within 30min of injury.

corresponds w/ intracellular ATP depletion & lactate accumulation due to anaerobic glycolysis

104
Q

disaggregation of polysomes is a sign of

A

dissociation of rRNA from mRNA.

reversible injury

105
Q

disaggregation of granular and fibrillar elements of nucleus is a sign of..

clumping of nuclear chromatic is a sign of..

A

both: reversible cell injury.

perhaps due to change in pH

106
Q

glycogen loss in myocardium is a sign of…

A

reversible cell injury.

less mito ATP – use glycogen

glycogen stores can be depleted within 30 min of severe ischemia

107
Q

triglyceride droplet accumulation in cells is a sign of..

A

reversible injury, esp in hepatocytes. also in striated muscle injury and renal cells.

results from decreased synthesis of intracellular proteins within cell injury.

hepatocytes: decrease production of lipid acceptor proteins –> prevents incorporation of lipid into lipoproteins –> accumulate in cell

108
Q

vascular dementia vs. alzheimer’s

A

multiple lacunar infarcts: STEP-WISE decline in cognition

alzheimer’s: gradual decline

109
Q

which cells in testes are temperature sensitive

A

sertoli cells must more temperature sensitive (seminiferous tubules in general)

110
Q

which hormone is decreased in cryptoorchidism?

A

inhibin –

sertoli cells are very temperature sensitive and prone to heat-induced damage.

seminferous tubules become atrophic and hyalinized –> low sperm count.

leydig cells are NOT very temperature sensitive –> secondary sexual characteristics develop just fine.

111
Q

broadly speaking, tests that evaluate hepatobilary disease assess what 3 things

A

(1) liver functionality: PTT, bilirubin, albumin, cholesterol
(2) structural integrity & cellular intactness of liver (transaminase)
(3) bililary tract (ALP, gamma-glutamyl transferase)

112
Q

alkaline phosphatase

A

group of enzymes associated w/ metabolic activity in a number of tissues (liver, bone, intestine, kidney, placenta, leukocytes, some neoplasms)

primary source: BONE & LIVER

3x elevation = nonspecific finding for many liver disease.

113
Q

GGT (gamma glutamyl transpeptidase)

A

enzyme primarily in hepatocytes and biliary epithelia.

can be found in various extrahepatic tissues (kidney, spleen, pancreas, heart, lung, and brain)

NOT present much in bone.

therefore, useful to determine whether ALP is of hepatic or bony origin

114
Q

determine if ALP is of bony / hepatic origin

A

look at GGT

115
Q

lactate dehydrogenase measures

A

nonspecific test, evaluation of tissue injury or death

116
Q

CML vs. leukomoid reaction

A

CML: low leukocyte alkaline phosphatase score

117
Q

CD14

A

macrophage and monocyte.

receptor for LPS (activates macrophage)

118
Q

atypical reactive T cells in EBV are..

A

CD8+ T cells – ready to attack EBV infected B cells

119
Q

how does EBV get into B cells

A

CD21