test #34 4.22 Flashcards Preview

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Flashcards in test #34 4.22 Deck (113):
1

3 determinants of malignant potential of an adenomatous polyp

1. size (> 4cm have 40% risk of malignancy

2. histology: villous more prone to be malignant than tubular

3. degree of dysplasia

2

bell curve: what %age of population falls in 1 standard deviation? 2? 3?

1 standard deviation = 68%
2: 95% (2.5 below, 2.5 above)
3: 99.7

3

where is CCK made

I cells of duodenum and jejuneum.

increase pancreatic enzyme secretion and gallbladder contraction

decrease gastric emptying

4

where is vasoactive intestinal peptide made?

pancreas & parasympathetic ganglia

stimulates intestinal water secretion, counteracts gastrin, promotes bicarb secretion for pancreas

5

classic galactosemia is inherited as..

autosomal recessive

lack galactose-1-phosphate uridyltransferase

6

3 steps of deglutition (swallowing)

1. oral: voluntary
food bolus collected at back of mouth, lifted upwards to posterior wall of pharynx

2. pharyngeal, involuntary
pharyngeal muscle contractions propel food bolus to esophagus

3. esophageal phase
- enters & stretches walls. peristalsis begins above site of distention and moves food down.

7

difficulty swallowing "felt at the throat"

cricopharyngeal muscle dysfunction. diminished relaxation of pharyngeal muscles during swallowing.

8

how does cricopharyngeal muscle dysfunction lead to zenker diverticulum?

diminshed relaxation of pharyngeal muscles during swallowing demands more force to move food bolus down.

more intense contraction of pharyngeal muscles --> increase oropharyngeal intraluminal pressure.

eventually, pharyngeal mucosa herniate through muscle fibers in zone of weakness (posterior hypopharynx).

only mucosa --> FALSE / pulsion (as opposed to all walls of organ --> true / traction)\

can lead to aspiration of food -- bc food stuck in diverticulum high up

can be palpated as lateral neck mass

9

mediastinal lymphadenitis (TB, fungal) can lead to what esophagus problem

scarring & traction --> true diverticula, mid portion of esophagus

10

hemoglobin synthesis in fetus (4)

yolk sac, liver, spleen, bone marrow.

liver begins HbF 10-12 wks of gestation --> spleen --> bone marrow.

11

when does HbF transition to HgA?

HbF (a2y2) --> HbA (a2b2) during first 6 months.

12

a2d2 (HbA2)

normal variant of human hemoglobin. 2-5% of adult hemoglobin

13

hemoglobin gower (z2e2)

earliest hemoglobin in fetus.

synthesized in yolk sac, replaced by hemoglobin portland --> hemoglobin gower 2 --> hemoglobin F (10-12 wks)

14

hemoglobin bart

gamma4.
no alpha made.
alpha thalaseemia.

high affinity for oxygen, never gives it up, get hydrops fetalis

15

muscles that attach to clavicle

-pec major (inferomedial)
-deltoid (inferolateral)
-subclavius (inferolateral)
-trapezius (superolateral)
-sternocleidomastoid (superior medial aspect)

16

where does sternocleidomastoid articulate

3 points:
manubrium, medial clavicle, and mastoid

17

rhomboid muscle articulation

vertebral bodies to medial border of scapula

18

pec minor articultation

3-4th rib, insert on coracoid process

19

serratus anterior

1-8th rib, insert on medial border of scapula

20

subclavius muscle

originates on 1st rib, inserts on inferolateral aspect of clavicle

21

floor of anatomical snuff box

scaphoid and trapezium

22

dupuytren's contracture

benign, slowly progressive fibroproliferative disease of palmar fascia.

as scarring progresses, nodules form on palmar fascia, fingers gradually loose flexibility, eventually resulting in CONTRACTURE that draws fingers in FLEXION

23

celiac comes out at what vertebral level? SMA & renal artery? IMA?

celiac: T12
SMA & renal: L1
IMA: L3

24

transverse duodenum lies at what vertebral level?

L3, between aorta and SMA (can be compressed)

25

ligament of treitz

suspensory ligament of duodenum (connect right crus of diaphragm to duodenal jejunal flexure)

26

what can be compressed when mesenteric fat is lost between SMA and aorta?

left renal vein & transverse duodenum

also occurs w/ pronounced lordosis, or surgical correction of scoliosis

27

filtration fraction =

GFR/RPF

usu = .2 (1/5th of RPF is filtered)

how much of renal plasma flow is filtered

28

how does RPF, GFR, and FF change in SEVERE dehydration

RPF falls a lot
GFR falls less (efferent arteriole constricts to maintain some GFR)
FF goes UP

end up compensating to filter a larger amount of the little incoming renal plasma

29

what forms erythema migrans of ixodes bite? how does it look

erythematous macule that enlarges w/ advancing erythematous borders as BACTERIA MIGRATE slowly through skin outward from inoculation site

classically has central clearing, but NOT ALWAYS!

30

scrofula

caused by mycobacterium scrofulaceum.

found in and around environmental water sources.

characterized by lymphadenitis (usu cervical) in kids

31

leptospirosis & weil's disease

lepto:
exposure to animal urine.
no cutaneous manifestation
usu asymptomatic, self limited

progression to weil's:
jaundice, renal dysfunction, thrombocytopenia, bleeding

32

sucrose is..

fructose and glucose

33

lactose is..

galactose and glucose

34

maltose is..

glucose and glucose

35

which two dissacharides are in breast milk

maltose and galactose

36

what is starch made of..

major carbohydrate in plants

only glucose molecules:

-unbranched: amylose
-branched: amylopectin

37

what is cellulose made of..

linear polysach of glucose, mainly present in cell wall of plants.

not digested by GI enzymes.

composes one form of non-soluble dietary fiber --> bulk of fecal matter.

38

aldolase B deficiency

hypoglycemia after fructose ingestion due to phosphate trapping by fructose-6-phosphate.

39

essential fructosuria & galactokinase deficiency are..

MILD

40

fructose intolerance & classic galactosemia are..

more severe

41

violaceous discoloration of upper eyelids & raised violaceous scaling eruption on kuckles

heliotrope rash & grotton's sign.
(w/ proximal muscle weakness)

dermatomyositis.

usu elevated cpk

42

2 main diff between pemphigus vulgaris & bullous pemphigoid

pemphigus vulgaris 1. affects oral mucosa 2. ruptures easily

43

mutation in ALS?

copper zinc superoxide dismutase (SOD1)

44

rx for ALS

riluzole, decreases glutamate release

45

macroscopic changes in ALS

thin anterior roots, atrophy of precentral gyrus

46

PKU that does not alleviate w. phenylalanine restriction / tyrosine supplementation

dihydrobiopterin reductase deficiency.

needed for both

1. phenylalanine -> tyrosine
(via phenylalanine hydroxylase)

2. tyrosine -> DOPA
(via tyrosine hydroxylase)

"atypical" or "malignant" phenylketonuria

47

problems w/ dihydropterin reductase deficiency

inability to convert phenylalanine -> tyrosine, tyrosine -> dopa.

tetrahydrobiopterin is impt for tyrosine, DOPA, 5-HT and NO synthesis.

present w/ high prolactin bc can't make dopamine in tuberoinfundibular system

48

alkaptonuria

autosomal recessive
deficiency in homogentisic acid

(break down homogentistic acid, which is a toxic tyrosine byproduct, harmful to bone & cartilage)

49

PMNT

phenylethanolamine N-methyltranserase

convert NE -> E

need SAM (s-adenosyl-methionine) as cofactor --> s-adenosylhomocysteine

50

how does WPW present (2)

accessory pathway bypassing bundle of kent

(1) pre-excitation: first impulse through accessory path, then shortly thereafter via AV node.

(2) allows for recurrent, temporary tachyarrhythmias due to atrioventricular re-entry circuit involving AV node & accessory path

51

WPW pre-excitation on EKG

shortened PR interval ( makes for wider QRS

delta wave goes away in re-entrant tachyarrhythmia bc no longer pre-excitation

52

what can trigger malignant hyperthermia?

inhaled anesthetics (esp halothane)

& succinylcholine

53

why does malignant hyperthermia happen?

rx?

autosomal dominant

skeletal muscles hypersensitive to inhalation anesthetics (esp halothane) & succinylcholine.

defect on ryanodine receptors of sarcoplasmic reticulum. release too much Ca2+, stimulating ATP-dependent reuptake of Ca2+ into SR. excessive ATP consumption --> generate lots of heat

loss of ATP + heat --> muscle damage --> rhabdomyolysis --> release K+, myoglobin, creatinine kinase

dantrolene: prevent Ca2+ release from ryanodine receptors

54

phentolamine & phenoxybenzamine

alpha-adrengeric blockers

55

which drug causes increased triglyceride levels as side effect

cholestyramine (bile acid resins)

bile acid production increases, but so does hepatic production of TG and VLDL.

56

cholestyramine side effects (3)

bile acid resin:
- GI upset
- impaired nutrient absorption & drugs
- elevated triglycerides
- also increase cholesterol content of bile --> stones

57

niacin on triglycerides

reduces serum TGs

also decreases VLDL conversion to LDL (less LDL)

58

B6-deficiency related anemia

needed for hemoglobin synthesis. can cause hypochromic microcytic pyridoxine responsive sideroblastic anemia

59

segmental granulomatous large vessel arteritis

takayasu arteritis

60

when can hepatitis D virus cause infection?

when encapsulated with HBsAg.

hepatitis D is replication defective RNA.

- acute coinfection w/ hep B (hep B established to provide HBsAg) or superinfection of a chronic HBV carrier

61

common extrahepatic disease in chronic hep C infection (2)

(1) membranous glomerulonephropathy
(2) mixed cryoglobulinemia

62

2 forms of chronic gastritis?
acute gastritis?

chronic:
type A: autoimmune (fundus/body)
type B: h. pylori bacteria (antrum)

acute:
disruption of mucosal barrier
(stress, NSAID, alcohol, uremia, burns (curling ulcer), brain injury (cushing ulcer), chemo, shock..

63

autoimmune type A chronic gastritis

autoantibodies to parietal cells / intrinsic factor, results in

1. achlorhydia
2. anemia (no b12)

also increased risk of gastric adenocarcinoma

64

type B gastritis is associated w/ increased risk of

Maltoma & gastric adenocarcinoma

65

what's one way acute gastritis can be differentiated from chronic gastritis?

acute: neutrophil predominant

chronic: lymphocyte & plasma cell

66

what kind of reaction does a foreign body cause? how does this happen.

granuloma!

takes several days/wks. antigen that cannot be eradicated by usu mechanism

activated Th1 CD4+ cells secrete IFN-gamma, activates macrophages. macrophage secrete THF-alpha, which forms granuloma.

67

Marjolin's ulcer

aggressive, ulcerating squamous cell carcinoma.

presents in an area of previously traumatized, chronically inflammed, or scarred skin.

malignant transformation occurs long after initial trauma, usu > 10yrs later.

68

time frame of wound healing

1. inflammatory (immediate):
- clot & clean
2. proliferative (2-3 d later):
- granulation & contrature
3. remodeling (1wk later):
- type III -> type I

69

which class III antiarrhythmics is not associated w/ Tdp

amiodarone (silver lining!)

70

which class I antiarrhythmics predispose to Tdp?

class IA (have class III properties too)

71

adenosine on EKG

expect it to prolong PR, but cleared so quickly (t1/2: <10seconds)

72

digoxin 2 fxn

1. increase vagal tone of AV: antiarrhythmic
2. increase contractility

73

characterestics of glioblastoma multiforme

necrosis and vascular proliferation

pseudopalisading

74

prognosis of glioblastoma

highly malignant. will die within 1-2 years

75

cyst formation & rare mitosis in brain suggests?

colloid cyst -- pathologically benign tumor, usu in 3rd ventricle. can cause lethal obstructive hydrocephalus

76

reticulin deposits and chronic inflammatory infiltrate in brain suggests?

pleomorphic xanthoastrocytoma.

variant of astrocytoma, can progress to GBM

77

what causes congenital pyloric stenosis? acquired?

congenital: smooth muscle hypertrophy of pyloric muscularis mucosae

acquired: associated w/ gastritis, peptic ulcer in pylorus, neoplasm

78

psoas articulation

transverse processes & lateral aspect of T12 through L5 vertebrae --> down across pelvic brim anterior to hip joint capsule & deep to inguinal ligament to insert into the lesser trochanter (shared tendon w/ iliacus)

79

psoas abscess forms from..

direct spread of infection from adjacent structure (vertebral bodies, appendix, hip joint)

or hematogenous / lymphatic seeding from distant site

80

psoas sign

movement that causes psoas muscle to be stretched/extended.

associated w/ appendicitis

81

quadratus lumborum

coarses posterior to psoas muscle. connects 12th rib & upper lumbar vertebra to iliac crest --> extension & lateral flexion of vertebral column

82

rx for warfarin reversal

fresh frozen plasma

(vit K would help, but takes time bc need to resynthesize clotting factors)

83

aminocaproic acid

antifibrinolytic agent -- inhibit plasminogen activators

84

protamine

heparin reversal, binds/inactivates heparin

85

what's contained in cryoprecipitate vs. fresh frozen plasma

fresh frozen plasma: all coagulation factors

cryoprecipitate: only cold soluble proteins: factor VIII, fibrinogen, vWF, and vitronectin

86

serum vs plasma

serum = plasma w/o clotting factor

87

desmopressin in heme

increases factor VIII activity (in pts w/ hemophilia A & vWD)

88

most common cause of overdose related deaths?

prescription opiod pain relievers

(exceeds heroin + cocaine combined)

due to increase in prescribing w/o adequate drug monitoring.

89

potency of inhaled anesthetic depends on..

inversely related to minimal alveolar concentration

when inhaled anesthetic administered at constant rate over prolonged period, its partial pressure in brain = partial pressure in other compartments.

since concentration in brain directly proportion to partial pressure, it is a measure of potency

intrinsic property of anesthetic, does not depend on surgery, duration, sex/height/weight.

90

anesthetics arteriovenous concentration gradient is a measure of

measure of solubility in tissue.
high = increased time for blood to be saturated = slow time of onset

91

blood/gas partition coefficient is a measure of

solubility in blood --

high blood/gas partition = very soluble in blood = slower onset of action

92

steepness of arterial tension curve of inhaled anesthetic measures..

depends on solubility of anesthetic in blood.

partial pressure rises steeply when less soluble

93

2 fxn of von willebrand factor

1. protect factor VIII from degradation
2. connects collagen to platelets (via GpIb)

94

what activates protein C

thrombin-thrombomodulin complex

95

von Gierke disease

type 1 glycogen storage disease
autosomal recessive

deficiency glycogen phosphorylase

cannot do: glycogen -> glucose 1-phosphate
via glycogen phosphorylase, breaks alpha (1,4) glucosidase link

severe fasting hypoglycemia, increased glycogen in liver, increased blood lactate.

NOTE: in muscle
[glycogen-> glucose 1-phosphate]
via myophosphorylase]

btw: glucose 1-phosphate --> glucose 6-phosphate (via phosphoglucomutase) and then...

in LIVER:
glucose 6-phosphate -> glucose
via glucose phosphorylase

96

synthesis of glycogen

glucose 6-phosphate --> glucose 1-phosphate
via phosphoglucomutase

glucose 1-phosphate --> UDP glucose
via: UDP-glucose pyrophosphorylase

UDP-glucose -> glycogen
via: glycogen synthase
(stimulated by insulin, inhibited by PKA)

branches made via branching enzyme

97

pompe disease

type 2 glycogen storage disease

deficient in lysosomal alpha 1,4-glucosidase (aka acid maltase)
[limited amount in lysosomes]

trashes the pump --> cardiomyopathy, liver, and muscle problems

early death

98

cori disease

type 3 glycogen storage disease

alpha 1,6 glucosidase
[debranching enzyme]

milder than type 1, normal blood lactate

99

mcArdle disease

type 5 glycogen storage disease

myophosphorylase

can't use glycogen in muscle

cannot do: glycogen -> glucose 1-phosphate

[note, in muscle glucose 1-phosphate -> glucose 6-phosphate via phosphoglucomutase]

glucose 6-phosphate is used as is! no glucose phosphorylase, bc don't want to release glucose into circulation

symptoms: decreased exercise tolerance, myoglobinuria, muscle pain w/ activity

relieved w/ exogenous glucose

100

breakdown of glycogen requires 4 enzymes (in liver).. [3 in muscle]

1. glycogen phosphorylase
glycogen -> glucose 1-phosphate

2. debranching enzyme
glycogen -> glucose 6-phosphate

3. phosphoglucomutase
glucose 1-phosphate -> glucose 6-phosphate

MUSCLE just uses glucose 6-phosphate

4. glucose 6-phosphatase (only in liver)
glucose 6-phosphate -> glucose

101

limit dextran

when there are 4 residues on a glycogen branch (glycogen phosphorylase already did its thing)

first: 4-alpha-D-glucanotransferase takes off 3 glucose 1-phosphates

second: alpha 1,6-glucosidase takes off 1 glucose 1-phosphate

102

how does HBV allow hepatitis D virus?

hep D = 35nm double-shelled particle.

HDAg + short ssRNA

needs to be COATED w/ HBsAg.

acute coinfection or superinfection of chronic HBV carrier.

only w/ HBsAg can it: penetrate hepatocyte, survive in cell, replicate viral RNA, and translate genome

103

constitutional symptoms, mid-diastolic rumbling murmur at apex, positional dyspnea, large pedunculated mass in left atrium suggests..

atrial myxoma

make lots of IL-6, constitutional symptoms

most common primary cardiac neoplasm.
approx 80% arise in left atrium

104

histology of atrial myxoma

scattered cells within a mucopolysaccharide stroma, abnormal blood vessels (lots of VEGF), and hemorrhaging (hemosiderin depositions)

al

105

drug-induced acute interstitial nephritis characterized by..

eosinophilia [serum & urine]

drug acts as hapten, hypersensitivity

106

down syndrome, ataxia-teleangiectasia, and NF-1 associated w. increased risk of..

ALL

107

twinning:
cleavage during 0-4 days (from zygote to morula)

dichorionic diamniotic

108

twinning:
cleavage during 4-8 days (from morula to blastocoele)

monochorionic diamniotic

109

twinning:
cleavage during 8-12 days
(from blastocoele to embryonic disc)

monochorionic monoamniotic

110

twinning
cleavage from 13+ days

fused babies

111

dizygotic twins

dichorionic diamniotic

112

dichorionic monoamniotic

does NOT EXIST

chorion = outer cover

113

how long does busipirone take to work

several weeks

5-HT1a receptor agonist, safe and effective. delayed response for 2 wks.

long-term rx. 1st line for generalized anxiety disorder. not as dependent.