test #31 4.20 Flashcards Preview

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Flashcards in test #31 4.20 Deck (119):
1

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

posterior descending branch of RCA.

ST elevations in leads II, III, aVF

2

transmural ischemia of interventricular septum on EKG?

ST elevation in leads V1 V2

3

transmural ischemia of anterior left ventricular wall on EKG?

ST elevation in V3 V4

4

occlusion of proximal LAD infarcts.. causes on EKG?

infarts anteroseptal transmural ischemia. ST elevations in V1-V4

5

anterolateral infarct of left ventricle on EKG?

LCX or LAD -- V4-V6

6

lateral wall of left ventricle infarct on EKG?

I, aVL & V5-V6

7

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

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

aganglionic segment -> constricted bc cannot relax

8

torsades

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

prolonged QT caused by..

class IA and III antiarrhythmics
(not amiodarone)
phenothiazines
TCAs

10

lidocaine fxn by..

blocking Na+ channels

11

penicillins are structurally stimilar to

terminal d-ala-d-ala of peptidoglycan molecule

blocks transpeptidase

12

N-acetylmuramic acid and N-acetylglucosamine are

peptidoglycan precursor molesules of cell wall in bacteria

13

sulfonamide antibiotic mechanism? trimethoprim

sulfonamides: compete w/ PABA (paraaminobenzoic acid) for incorporation into folic acid..

trimethoprim: block dihydrofolate reductase

14

staph epidermidis infxn?

rx:

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

rx for staph epidermidis bactermia. if not..?

aggressive! vancomycin + rifampin + gentamycin

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

16

AML blasts will stain positive for

peroxidase (since Aur rods have MPO)

17

TdT in lymphocytes

terminal deoxynucleotidyl tranferase

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

mature of immature B and T cells

18

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

TRAP (tartare resistant acid phosphatase)

B-cells! CD20+

splenomegaly, fatigue, pancytopenia

19

glomus body & glomus tumor

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

skin presentation of histiocytosis

erythematous papules, nodules, and/or scaling plaques

21

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

low Na
high K
low Cl
low HCO3

22

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

primary -- loose aldosterone, cortisol, and androgens

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

23

Na+ in hyperaldosterone?

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

24

why is supraspinatus injury most common of rotator cuff?

repeated impingement trauma between humeral head & acromion

abbductor

25

subacromial bursa location

under both acromion/clavicle & tendon of deltoid muscle.

sits on top of supraspinatus

26

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

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

positive trendelenburg sign

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

sciatic n. innervates all knee flexors except..

biceps femoris

29

Tzanck prep

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

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

30

primary vs. reactivation HSV-1 infxn

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

primary vs. reactivation of VZV infxn

reactivation won't cross midline either

32

latency means..

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

33

slow virus infection

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

S3 sound

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

murmur associated w/ HCM

dynamic LVOT -- mitral regurgitation -- systolic. or 'aortic stenosis' like??

36

pattern of drug administration for nitrates?

nitrate free interval every day. rapid tolerance

due to decreased vascular sensitivity & increased sensitivity to vasoconstriction

37

MAO inhibitors (phenelzine) fxn by..

IRREVERSIBLY bind. takes 2 wks post discontinuation to regenerate enzyme

wait before giving SSRI

38

SSRI + MAOi =

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

39

drug of choice for paroxysmal supraventricular tachycardia?

adenosine -- open K+ channels, hyperpolarize AV node.

(acts in manner similar to muscarinic cholinergics)

40

side effects of adenosine for PSVT?

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

41

side effects of amiodarone

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

42

lidocaine side effects/toxicity

neurologic symptoms usu

43

procainamide toxicity

usu drug-induced lupus syndrome

44

verapamil side effects

gingival hyperplasia and constipation

45

digoxin/digitalis side effects / toxicity

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

46

drug used for chemical stress test?

adenosine! causes bronchospasm, flushing, high grade block!

47

vomit pathway

proprionylCoA --> methymalonylCoA
(propionylCoA carboxylase + biotin)

methylmalonylCoA --> succinylCoA
methylmalonylCoA mutase

48

malonyl CoA comes from..

acetylCoA + acetylCoA carboxylase

49

methylmalonyl CoA comes from..

propionylCoA + propionylCoA carboxylase

50

hydrolysis in urea cycle

arginine to ornithine via arginase

51

transamination

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

usu requires B6

52

methylmalonic acidemia

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

53

parvovirus infxn in adult:

arthritis involving proximal interphalangeal, metacarpal knee, and ankle

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

54

hyaline membranes in ARDS

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

smell is from..

apocrine glands

56

apocrine glands

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

holocrine glands

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

58

eccrine (merocrine)

skin throughout body. except lips and glans penis.

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

59

mammary glands (lactation)

modified sweat glands. apocrine secretion.

60

aldosterone functions by..

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

which chemical increases urea transport in collecting ducts

ADH

62

inheritance of phenylketonuria?

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

63

ritodrine and terbutaline

b2 agonist. tocolysis. relaxes uterus. defer premature labor

64

inheritance of glucose 6 phosphate dehydrogenase

x-linked recessive

65

MOST structural abnormalities are inherited as..

autosomal dominant
(i.e. hereditary spherocytosis)

66

MOST enzyme deficiencies inherited as..

autosomal recessive

67

X-linked dominant? example

100% risk to female offspring of an affected male.

vitamin-D-resistant rickets

68

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

shortly after daughter strands synthesized.

69

DNA deaminating agents. repair?

nitrous acid.

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

70

how does alcohol cause pancreatitis

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

main causes of acute pancreatitis (2)

1. gallstones
2. alcohol abuse!

72

alcohol abuse leads to what hematological abnormality

macrocytosis (MCV) secondary to...
(1) poor nutrition: folate / b12
(2) direct toxicity of alcohol on bone marrow

73

3 indicators of chronic alcohol abuse

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

macrocytosis can occur independently of folate or cobalamin deficiency

74

chediak-higashi

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

wiskot aldrich

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

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

chediak-higashi (defective neutrophil phagolysosome function)

77

side effects of lithium

LMNOP

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

monitor BUN/creatinine and TSH

78

clozapine atypical antipsychotic can cause

agranulocytosis & seizures

79

risperidone can cause..

increase prolactin.

galactorrhea and amenorrhea

80

trazodone side effects

painful erection (priapism), orthostatic hypotension, sedaition

81

olanzipine/clozapine side effect

weight gain

82

ziprasidone side effect

prolong QT

83

atypical antipsychotic with least side effect

aripripazole

84

presentation of polycythemia vera

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

examples of JAK STAT signalling

ERO

86

describe JAK STAT signalling

nonreceptor tyrosine kinase.

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

87

examples of RTK activity

insulin, IGF-1, EGF

88

li-fraumeni syndrome associated w/ which cancers

- sarcomas and tumor of breast
- brain
- adrenal cortex

89

photosensitivty in porphyria due to

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

90

where does H. pylori like living in the stomach?

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

where can H. pylori live?

ONLY in areas of gastric metaplasia!

can't live in normal duodenum

92

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

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

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

viral myocarditis

94

interstitial inflammatory infiltrate of mononuclear inflammatory cells & eosinophils in heart

hypersensitivty myocarditis

95

diptheric myocarditis

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

distension of individual myofibers w/ intracellular trypanosomes in heart?

chagas disease, trypanosoma cruzi

97

most common cause of end state renal failure in US

diabetic nephropathy

98

kidney disease w/ hyperuricemia?

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

psychogenic erectile dysfunction

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

100

what sexual features decrease w/ age

longer refractory period, take longer to achieve erection

sexual desire does not fall

101

most common mediations causing impotence

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

102

signs of irreversible injury in heart

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

myofibril relaxation results from..

reversible injury:
within 30min of injury.

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

104

disaggregation of polysomes is a sign of

dissociation of rRNA from mRNA.

reversible injury

105

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

clumping of nuclear chromatic is a sign of..

both: reversible cell injury.

perhaps due to change in pH

106

glycogen loss in myocardium is a sign of...

reversible cell injury.

less mito ATP -- use glycogen

glycogen stores can be depleted within 30 min of severe ischemia

107

triglyceride droplet accumulation in cells is a sign of..

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

vascular dementia vs. alzheimer's

multiple lacunar infarcts: STEP-WISE decline in cognition

alzheimer's: gradual decline

109

which cells in testes are temperature sensitive

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

110

which hormone is decreased in cryptoorchidism?

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

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

(1) liver functionality: PTT, bilirubin, albumin, cholesterol

(2) structural integrity & cellular intactness of liver (transaminase)

(3) bililary tract (ALP, gamma-glutamyl transferase)

112

alkaline phosphatase

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

GGT (gamma glutamyl transpeptidase)

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

determine if ALP is of bony / hepatic origin

look at GGT

115

lactate dehydrogenase measures

nonspecific test, evaluation of tissue injury or death

116

CML vs. leukomoid reaction

CML: low leukocyte alkaline phosphatase score

117

CD14

macrophage and monocyte.

receptor for LPS (activates macrophage)

118

atypical reactive T cells in EBV are..

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

119

how does EBV get into B cells

CD21