test #39 4.29 Flashcards Preview

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Flashcards in test #39 4.29 Deck (159):
1

what does "end-organ" blood supply mean?

interruptions in blood flow lead to formation of infarct

renal: small number of collaterals between segmental renal arteries

brain too?

2

recall nephrotic syndrome presents w/ 5 things

1. edema (loss of albumin / oncotic pressure
2. proteinuria
3. hyperlipidema
4. hypercoagulation (loss of antithrombin III & increased coag factors
5. infection (loss of immunoglobulins)

3

histology of crohn's vs. ulcerative colitis

crohns: noncaseating granulomas & lymphoid aggregates (Th1 mediated)

ulcerative colitis: crypt abscesses (Th2 mediated)

4

blood in crohn's vs. ulcerative colitis

crohn's: + occult blood

ulcerative colitis: gross bleeding

5

string sign on barium swallow

crohn's disease: narrowing of the intestinal segment due to inflammation of intestinal wall

6

ulcers in crohn's? gross morphology?

1. linear or serpiginous ulcerations
2. cobblestone mucosa
3. transmural inflammatory infiltrate.

"string sign"

7

gross morphology of ulcerative colitis

1. mucosal & submucosal inflammation
2. friable mucosal pseudopolyps w/ freely hanging mesentary

loss of haustra = lead pipe

8

cells in moles vs. choriocarcinoma

mole: only trophoblasts; swelling villi

choriocarcinoma: trophoblasts & syncitiotrophoblasts; NO VILLI

9

clinical presentation of:
complete vs. partial hydatidiform mole

both: vaginal bleeding & cramps/pressure

complete:
-SIZE greater than dates &
-extremely HIGH b-hCG

partial:
-normal size
-b-hCG high/normal

[hCG can lead to:
- hyperemesis gravidarum
- pre-eclampsia
- hyperthyroidism
- theca-lutein cysts

10

macroscopic: complete vs. partial hydatidiform mole?

complete: friable mass of cystic, thin-walled, grapelike structures. exclusively TROPHOBLASTIC TISSUE. "bunch of grapes"

partial: mix of normal & gross enlarged chorionic villi; FETAL PARTS (fetus, cord, amniotic membrane)

11

micropscopic appearance: complete vs. partial hydatidiform mole?

complete: enlarged, EDEMATOUS villi w/ extensive & diffuse trophoblastic HYPERPLASIA
(no fetal tissue)

partial: some enlarged vili w/ more moderate & FOCAL trophoblastic hyperplasia.
- normal villi & fetal tissue also present

12

karyotype of complete & partial hydatidiform mole?

complete: completely PAPA 46 XX or 46 XY (sperm fertilizes empty egg; sperm chromosomes duplicate usu: 46 XX more common)

partial: 69 XXX or XXY
(TRIPLOID)
usu 1 egg w/ 2 sperms

13

risk of malignancy in complete & partial hydatidiform mole?

complete: 15-20% risk of malignant trophoblastic disease

partial: low risk of malignancy <5%

14

where is TRH made?

paraventricular nucleus of hypothalamus

15

main regulator of TSH section?

T3

- T3 acts on paraventricular nucleus to decrease synthesis/release of TRH.
- down regulate TSH gene transcription & TRH receptor expression

16

T4 in peripheral tissues

converted to T3 or rT3 by specific deiodinases

(t3 cannot become T4 or rT3)

17

potency, half-life, metabolism of T4, T3, rT3

half-life
T4: 7 days
T3: 1 day
rT3: <1 day

cleared via glucuronidation in liver

[t3 not prescribed bc short half-life & rapid GI absorption = wide fluctuations]

18

acute acalculous cholecystitis

acute inflammation of gallbladder in absence of stones.

stasis & ischemia

PE: jaundice & palpable right upper quadrant mass = NOT SEEN IN calculous cholecystitis

complications: gangrene, perforation, emphysematous cholecystitis -- infxn w/ gas-producing agent: clostridium, e. coli

usu in hospitalized patients & severely ill

19

porcelain gallbladder

diagnosed on abdominal radiograph: rim of calcium deposits outline gallbladder

associated w/ gallbladder carcinoma

20

cholechondral cysts

congenital dilations of common bile duct

21

chronic cholecystitis results in..

thickening of gallbladder wall.
US: shruken, fibrosed gallbladder

22

clornarchis infxn of gallbladder is associated w..

brown pigment stones

23

black vs. brown gallstones

pigment stones

black: intravascular hemolysis
brown: biliary infxn

24

how does valsalva affect heart?

decrease preload.

exhale against closed glottis

25

systemic mastocytosis

abnormal proliferation of mast cells & increased histamine secretion

--> increase histamine --> gastric hypersecretion

can see nests of mast cells in bowel mucosa

26

Rokitansky-Aschoff sinus

chronic cholecystitis:

chemical irritation from long-standing cholethiasis

herniation of gallbladder mucosa into muscular wall --> Rokitansky-Aschoff sinus: ducts in muscle

late complication: porcelain gallbladder

27

mast cells in GI tract?

systemic mastocytosis!

28

systemic mastocytosis

mast cell proliferation in bone marrow & other organs

increase histamine

1. GI: increased gastric acid
- inactivation of pancreatic & intestinal enzymes --> diarrhea
- also N/V, cramps, ulcer

2. syncope, flushing, hypotension, tachycardia, bronchospasm

3. pruitus, uticaria, dermatographism

29

H2 receptors increase intracellular

cAMP

(gastrin/Ach = Ca2+)

30

gastrin & Ach increase intracellular..

Ca2+

(H2 = cAMP)

31

most potent action of gastrin

most potent: increase histamine synthesis & release by ECL cells

also: stimulates Ca2+ and acid release from parietal cells

32

what intracellular mediators increase H+ efflux from parietal cells

cAMP and Ca2+

via H+/K+ ATPase

33

6-mercaptopurine / azathioprine blocks what enzyme?

PRPP amidotransferase
inhibit de novo purine synthesis after being converted to active metabolites by HGPRT

34

how is 6-mp / azathioprine degraded?

xanthine oxidase

reduce dose when also on allopurinol

35

pentostatin

cytotoxic purine that is an irreversible inhibitor of ADA

36

cladribine

cytotoxic purine analog that is resistant to degradation by ADA

37

retroperitoneal structures

SAD PUCKER

Suprarenal/adrenal
Aorta / IVC
Duodenum (2-4th)

Pancreas (except tail)
Ureters & Bladder
Colon (descending & ascending)
Kidney
Esophagus (lower 2/3rd)
Rectum (partial)

or:
1. major vessels:
- abdominal aorta
- IVC
- their branches

2. solid organs:
- pancreas (except tail)
- kidney
- adrenal glands

3. hollow organs:
- parts 2/3 & part of 4 of duodenum
- ascending & descending colon (secondarily)
- rectum
- ureters
- bladder

4. vertebral column & pelvic muscles

38

retroperitoneal hematoma (in a stable patient) associated w/

abdominal/pelvic trauma

PANCREATIC injury --> retroperitoneal hematoma

39

abdominal blow from malpositioned seat belt / steering wheel --> retroperitoneal hematoma (in a stable patient) bc of damage to

PANCREAS

40

transverse colon, spleen, liver..

INTRAperitoneal organs

41

testicular malignancy w/ hyperthyroidism

must secrete b-hCG

choriocarcinoma; disordered syncitiotrophoblasts & cytotrophoblasts.

hematogenous metastasis to lung, liver, brain.

can produce gynecomastia or hyperthyroidism (B hCG like LH & TSH)

42

95% of all testicular tumors are..

germ cell tumors, often malignant, in young men

43

testicular tumor w/ fried-egg appearance, high placental ALP?

seminoma! malignant, painless, usu 3rd decade, late mets, excellent prognosis

44

testicular tumor w/ schiller-duval bodies and high AFP

yolk-sac (endodermal sinus tumor)

45

presentation of teratoma in male scrotum

may be malignant. benign in children though.

50% have both b HCG and AFP elevations

46

malignant hemorrhagic mass w/ necrosis in testes w/ glandular/papillary morphology

embryonal carcinoma

worse prognosis than seminoma

usu mixed w/ other types

associated w/ elevated bHCG.
also AFP if mixed

47

testicular nongerm cell tumors

1. Leydig cell
2. Sertoli cell
3. testicular lymphoma

mostly benign

48

Reinke crystal in testicular tumor

Leydig cell tumor, nongerm cell.

androgen producing, gynecomastia in men, precocious puberty in kids.

golden brown colour

49

Sertoli cell tumor in male

androblastoma from sex cord stroma

50

most common testicular malignancy in older men

testicular lymphoma

not a primary cancer, usu arises from lymphoma mets to testes

aggressive

51

demographics of squamous cell carcinoma

asia, africa, south america

associated w/ HPV and lack of circumcision

52

precursor in situ lesions of squamous cell carcinoma of penis

1. bowen disease
2. erythroplasia of Queyrat
3. bowenoid papulosis

53

bowen disease

precursor lesion to SCC of penis

on penile shaft
leukoplakia

54

erythroplasia of Queyrat

precusor lesion of SCC of penis

on glans
erythroplakia

55

Bowenoid papulosis

precursor lesion to SCC of penis

reddish papules

56

priapism associated w/ (3)

painful sustained erection

1. trauma
2. sickle-cell: trapped RBC
3. medications: anticoagulants, PDE-5 inhibitors, cocaine, alpha-blockers, trazodone

57

hCG is structurally similar to (3)

FSH, LH, TSH

58

which hormones can bind to TSH receptors

TSH and HCG (at much lower affinity)

note: FSH cannot! even though structurally similar!

59

cranial n. emerge from..

CN III and IV
oculomotor & trochlear (dorsal)
midbrain

CN V
pons

CN VI, CN VII, VIII, IX,
between pons & medulla

CN X
between olive & medulla

CN XI
spinal cord

CN XII
between pyramid and olive

60

which is the only CN to emerge dorsally

CN IV trochlear
dorsal midbrain

61

anterior pons lesion

dysarthria & ataxic hemiparesis

-corticopsinal tract (contralateral hemiparesis & babinski)
-corticobulbar tract (contralateral lower facial palsy & dysarthria

also affect pontine nuclei & pontocerebellar fibers --> contralateral dysmetria & dysdiadochokinesia

62

lesions of cerebellum produce (contralateral/ipsilateral lesion)? lesions of pontocerebellar fibers in basis pontis?

cerebellar: ipsilateral

pontocerebellar fibers: contralateral
(bc fibers enter cerebellum through contralateral cerebellar peduncle)

63

where does facial n arise?

pontomedullary junction
level of facial colliculus
below middle cerebellar peduncle

64

middle cerebellar peduncles

incoming information from cerebrum to cerebellum, either side of pons

65

where does trigeminal n arise

lateral aspect of midpons, at level of middle cerebellar peduncle

66

where does hypoglossal n arise

preolivary sulcus at level of rostral medulla

67

where does oculomotor n. arise?

at level of superior colliculus & red nucleus (midbrain)

68

where does trochlear n. arise

behind midbrain
level of interior colliculus

level of red nucleus.

only cranial n. to decussate before innervate target

69

what is the only CN to decussate?

trochlear, CN IV

70

glucocorticoids increase protein synthesis in..

LIVER (related to gluconeogenesis & glyocgenesis, proteolysis, lipolysis)

increase synthesis of PEP carboxykinase & glucose 6-phosphatase, glycogen synthetase

71

major effects of glucocorticoids (mnenomic)

BIG FIB

increase:
1. blood pressure a1 receptor (permissive)
2. insulin resistance
3. gluconeogenesis, glycogenesis, proteolysis, lipolysis (synthesize more PEP carboxykinase & G 6-phosphatase & glycogen synthetase

decrease:
1. fibroblast production of collagen
2. immune system
- inhibit production of leukotrienes and prostaglandins (block phospholipase A2 cleavage)
- inhibit leukocyte adhesion (neutrophilia)
- block histamine release from mast cells
- reduce eosinophils
-block IL-2 production

3. bone formation
-decrease osteoblast activity
- increase renal Ca2+ wasting
- decrease Ca2+ GI absorption

72

what receptor does glucocorticoids upregulate

alpha-1 BLOOD PRESSURE

73

what receptor does T3 upregulate?

beta-1 HEART RATE. etc

74

glucocorticoids favor catabolism of which 2 tissues? how?

skeletal muscle & adipose tissue

bc block insulin effects

results in proteolysis & lipolysis

75

glucocorticoid induced decrease in fibroblast activity causes (2)

1. skin thinning: purple striae, easy damage
2. CT around capillary thin --> easy bruising

76

positive skew

smaller numbers predominant in the data set

long slope / tail extends in positive direction

mean > median > mode

median = better measure of central tendency here

77

negative skew

larger numbers predominate in data set

long slope / tail extends in negative direction

mean < median < mode

median is better measure of central tendency here

78

carbon tetrachloride CCl4

causes free radical injury
oxidized by P250 system
makes free radical --> reacts w/ structural lipids of cell membranes

lipid peroxidation --> lipid degradation and hydrogen peroxide formation --> vicious cycle

swelling of ER, destruction of mitochondria, increased membrane permeability

--> hepatic necrosis

79

symptoms of thyrotoxicosis

palpitations, nervousness, easy fatigability, fine tremor, diarrhea, hyperhidrosis, heat intolerance, weight loss, hyperreflexia, dermopathy, opthalmia

80

thyroid opthalmia

exopthalmos, conjunctival hyperemia, periorbital edema

81

exopathalmosis due to..

increased soft tissue mass in bony orbit

due to enlargement of extraocular muscles from myositis, fibroblast proliferation, and overproduction of ground substance in response to antithyroid antibodies.

82

finely granular eosinophilic granules in hepatocytes?

hepatitis B!

hepatocellular cytoplasm becomes filled w/ spheres & tubules of HBsAg

GROUND GLASS APPEARANCE

83

mallory bodies

eosinophilic big inclusion in hepatocytes. hepatocytes will also have fatty changes

ubiquinated keratin fibers

in liver of alcoholics

84

describe the PI3K signalling pathway

important for cell proliferation

growth factor
RTK
autophosphorylation
activates PI3K (PIP2 -> PIP3)
PIP3 activates Akt (protein kinase B), a serine/threonine specific protein kinase

Akt activates mTOR, which translocates to nucleus

-- cell survival, anti-apoptosis, angiogenesis.

85

mTOR activation is usu inhibited by? activated by

inhibited by PTEN (phosphatase & tensin homolog), removes phosphate added by PIP3

activated: growth factors & PIP3 (PI3K/Akt/mTOR)

86

what determines fate of pyruvate?

oxygen.

low oxygen: lactate dehydorgenase converts pyruvate -> lactic acid (regenerate NAD+)

oxygen: pyruvate dehydrogenase converts pyruvate -> acetyl CoA

87

soleus & paraspinal muscles contain what type of fibers

postural
type 1: red, slow twitch. ATP = oxidative metabolism

88

cells involved in granuloma formation (TB formation)

1. Th1 CD4+ cells secrete IFN-y
2. activates CD8+ cytotoxic T cells and macrophages
3. macrophages secrete TNF-alpha, important for granuloma formation

89

d-xylulose

monosaccharide that can be absorbed w/o action of pancreatic enzymes.

see if malabsorption due to pancreatic or intestinal pathology

90

dobutamine on the heart

B-adrenergic agonist
predominant B1 > B2

mostly affects myocardium

1. positive ionotropic: increased contractility. increased cardiac output, decreased ventricular filling presure

2. weakly positive chronotropic: increases heart rate. less pronounced than associated w/ dopamine

both increase myocardial oxygen consumption

3. increases cardiac conduction velocity (undesirable --> arrythmia)

91

nitroglycerin on HR

venous pooling -> reflex tachycardia

92

nitroglycerin on myocardial oxygen consumption

reduce preload --> reduce oxygen consumption, used to rx: angina pectoris.

93

what decreases pulmonary capillary wedge pressure

aka left atrial pressure?

decreased preload: i.e. nitroglycerin, furosemide

increased contracility: i.e. dobutamine

94

anything that increases perfusion also..

increases urine output!

increased renal perfusion.

95

warfarin in pregnancy

TERATOGEN. no.

96

where are snRNP synthesized? by which polymrease

in the nucleus, RNA pol II

97

how does sleep apnea lead to pulmonary HTN?

hypoxemia --> pulmonary vasoconstriction

50% will also develop systemic HTN due to chronic sympathetic cardiovascular stimulation (re: hypoxemia)

98

official diagnosis of narcolepsy

excessive daytime sleepiness, cataplexy, REM-sleep related phenomenon (like hallucinations and sleep paralysis)

recurrent lapses into sleep (minimum 3x/wk for 3 months)

atleast one of following:
1. cataplexy (loss of muscle tone w/ strong emotion

2. low CSF hypocretin

3. shortened REM latency

associated w/ hypnagogic or hynopompic hallucinations and sleep paralysis

99

most common cause of excessive daytime sleepiness

obstructive sleep apnea

constantly waking up w/ apnea

100

first generation antihistamines have what common side effects

chlorpheniramine and diphenhydramine

antimuscarinic, antialpha-adrenergic, anti-5HT

101

how do H1 receptor blockers work?

reverse blockade

decrease receptor activity by increasing proportion of inactive H1 receptors!

102

alcohol induced hepatic steatosis

decrease in free fatty acid oxidation

secondary to excess NADH / NAD+ ratio -->
(due to alcohol and acetaldehyde dehydrogenase)

1. promotes glyceraldehyde 3-phosphate -> glycerol 3-phosphate -> triglyceride synthesis

2. blocks TCA production of NADH -> promotes use of acetyl-CoA for ketogenesis and lipogenesis

mostly: decrease in free fatty acid oxidation secondary to excess NADH

also: impaired lipoprotein assembly/secretion, increase in peripheral fat catabolism

103

stain for lipids w/ (2)

sudan black or oil red O

104

what is transferrin & total iron binding capacity

hepatic synthesis of transferrin in markedly increased in states of F2+ deficiency.

transferrin always inverse to saturation
same direction as TIBC

high transferrin means increased serum total Fe2+ binding capacity

high transferrin -> low iron

low transferrin -> high iron

105

normal ferritin states

in plasma. usu 1/3rd saturated w/ Fe2+

106

iron panel in iron deficiency anemia (ferritin, transferrin, MCV, folate, neutrophils

low ferritin
high transferrin
low MCV (microcytic)

normal folate & neutrophils

107

cyanotic toe discoloration, renal failure following invasive vascular procedure suggests

atheroembolic disease of renal arteries (cholesterol lodged)

108

livedo reticularis

swelling of venules bc of clogged capillaries

many causes

109

isoniazid resistance (2)

1. stop catalase-peroxidase enzyme expression
2. genetic modification of mycolic acid synthesis enzyme

110

resistance to ethambutol

increased production of arabinosyl transferase

111

resistance to rifampin

mutation in gene for DNA-dependent RNA polymerase

112

resistance to streptomycin

modification of 30S ribosomal protein stxr

113

how does pyrazinamide work?

converted to pyrazinoic acid, lowers environmental pH in susceptible strains of TB.

must be converted to active form via pyrazinamidase

114

resistance to pyrazinamide?

modified pyrazinamidase (needed to convert pyrazinamide to active form)

115

tryptophan is essential amino acid & precursor for (3)

(1) niacin (nicotinic acid)
(2) 5-HT
(3) melatonin

116

Hartnup disease (defect & clinical manifestation)

defective intestinal & renal absorption of tryptophan.

clinical: niacin B3 deficiency: pellagra (dermatitis, neuro: ataxia, usu wax & wane,

117

differentiate Hartnup disease from Fanconi syndrome

both aminoaciduria.

Hartnup: lose neutral amino acids
- alanine, serine, valine, threonine, leucine, isoleucine, phenylalanine, tyrosine, tryptophan, histidine)

Fanconi: generalized amino aciduria
- will ALSO have proline, hydroxyproline, argigine

118

seborrheic keratosis

flat, greasy, pigmented squamous epithelial proliferation.

keratin-filled cysts.

look "stuck on"
head, trunk, extremities

common benign neoplasm on older people

associated w/ Leser-Trelat sign

119

Leser-Trelat sign

sudden appearance of multiple seborrheic keratosis, suggesting underlying malignancy

(GI, lymphoid)

120

riboflavin deficiency (B2)

FMN, FAD (needed for enzymes in ETC)

2 C's of B2

CHEILOSIS, glossitis, keratitis, conjunctivitis, photophobia, lacrimation, CORNEAL VASCULARLIZATION, seborrheic dermatitis

121

decarboxylation & transamination requires what cofactor

vitamin B6 (pyridoxine)

122

clinical presentation of pyridoxine B6 deficiency

anemia, peripheral neuropathy, dermatitis

123

tocopherol

vitamin E
free radical scavenger (antioxidant)

deficiency: myelopathy / neuro dysfunction

124

erythematous papules w/ central scale due to hyperkeratosis. "sandpaper-like" texture

can turn into cutaneous horns

actinic keratosis

precursor to squamous cell carcinoma

125

well-circumscribed RAISED papules & plaques covered w/ thick silver scale

psoriasis

usu scalp, trunk, extensors (elbow/knee)

126

spongiosis

edema of the epidermis

associated w/ atoptic dermatitis (type I HSR)

127

pityriasis rosea presentation

herald patch: pink/brown scale plaque w/ central clearing & collarette of scale on trunk, neck, extremities

followed by: maculopapular rash in "christmas tree" pattern along skin tension lines

128

patent PDA associated with..(3)

1. prematurity
2. congenital rubella
3. fetal alcohol syndrome

129

ductus arteriosus comes from what aortic arch

6th
(also proximal pulmonary artery)

130

1st aortic arch

maxillary artery

1=max

131

2nd aortic arch

stapedial / hyoid artery

stapedial is second

132

3rd aortic arch

common carotid & proximal internal carotid

C = 3rd letter of alphabet

133

4th aortic arch

left: aortic arch
right: right subclavian

4 -> 4 limbs, systemic

134

6th aortic arch

PDA & proximal pulmonary artery

135

path of right recurrent laryngeal & left recurrent laryngeal

right: under right subclavian

left: under PDA (lower)

136

tissue development of branchial cleft, arch, and pouch

cleft: ectoderm

arch: mesoderm (cartilage/muscle)

pouch: endoderm

137

rhomboid major innervation

dorsal scapular nerve

138

teres major innervation

subscapular nerve

adduct & medially rotate

139

inheritance of hereditary spherocytosis

autosomal dominant

140

describe HFE expression and regulation of Fe2+ load

autosomal recessive

basolateral surface of epithelial cells in small intestine crypts..

complexes w/ B2 microglobulin, binds to transferrin receptor to regulate endocytosis of transferrin/Fe2+ complex (ferroportin)

iron released into cell: added to iron regulatory pool --> DETERMINES intensity of APICAL Fe2+ UPTAKE

mutation in HFE -> unregulated Fe2+ absorption

--> liver cirrhosis & hepatocellular carcinoma

141

two types of amyloid deposits in alzheimer's disease

1. brain parenchyma: senile plaques

2. brain vascular walls: amyloid angiopathy. damage media & adventitia, cause thickening of basal membrane, stenosis, and fragmentation of internal elastic lamina

can both be seen in healthy elderly individuals

142

pseudodementia

depression in elderly, can cause confusion & declining mental function

143

histology of Pick's disease?

atropy of frontotemporal regions.
can see spherical tau protein aggregates (intracellular)
(don't survive neuron, don't serve as marker for disease progression)

social disinhibition, speech abnormalities, and emotional flattening

144

gross/microscopic features of craniopharyngioma

1. calcified cysts: lined w/ stratified squamous epithlium
2. keratin pearls
3. yellow, viscious fluid rich in cholesterol crystals

145

6 complications of crohns

1. intestinal-
fistula, stricture, perianal disease, risk of adenocarcinoma

2. skin: pyoderma gangrenosum, erythema nodosum

3. joint: arthritis, ankylosing spondylitis

4. eyes: iritis, uveitis, episcleritis

5. malabsorption:
oxalate kidney stone, anemia, hypoproteinemia, b12 & folate def, gallstones

6. liver: cholangiocarcinoma

146

pyoderma gangrenosum

deep ulcer w/ violaceous border, usu on leg

associated w/ ulcerative colitis & crohns

147

describe oxalate excretion in gut.

Ca2+ binds oxalate --> insoluble Ca2+ oxalate salts --> excretion

148

how does crohn's disease lead to increased kidney oxalate stones?

impaired bile acid reabsorption. bile acid bind lipid & prevent reabsorption. Ca2+ binds to this too --> soap complexes

less Ca2+ to bind to oxalate --> increased oxalate absorption

149

oxalate stones in kidney, think (2)

(1) ethyelene glycol posioning
(2) crohn's disease

150

what does window period in HBV infection refer to?

time when HBsAg is down, but HBsAb is not yet up.

HbcAb IS detectable in window period --> diagnose HbsAg cleared

151

most specific marker for diagnosis of ACUTE hep B

IgM HbcAb (window period)

152

most common appendiceal tumor

carcinoid

153

octreotide mechanism

analog of somatostatin

inhibit secretion of many hormones

used for carcinoid & VIPoma

154

ondansetron

potent anti-emetic

selectively block 5HT-3

155

3 histological features in acute hepatitis

1. diffuse ballooning degeneration: hepatocyte swelling

2. mononuclear cell infiltrate

3. councilman bodies (eosinophilic apoptotic hepatocytes

156

aminoglycoside mechanism of resistance

bacterial transferase enzymes inactivate drug by acetylation, phosphorylation, adenylation

157

ONLY renal stone that is radiolucent

uric acid stone

158

how is Fe2+ absorption regulated (2)

1. hepcidin (internalize basolateral ferroportin -> decrease transport across intestinal epithelium & decrease release from macrophages)

2. HFE -> encourages ferroportin to bring in Fe2+ basolaterally, increasing enterocyte Fe2+ store, increasing apical iron absorption via DMT-1

hepcidin: increases iron stores in macrophages
HFE: decreases iron reabsorption in GI

159

most common malignancy of SMALL BOWEL

carcinoid (esp appendix)