test #33 4.22 Flashcards Preview

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Flashcards in test #33 4.22 Deck (114):
1

antiarrhythmic prolonging QT & bradycardia (prolonged PR)

sotalol

beta-blocker w/ class III antiarrhythmic properties

2

how do beta blockers work?

(1) slow AV nodal conduction
(2) prolonging phase 4 depolarization

3

triglyceride breakdown. fate of fatty acid & glycerol?

triglyceride --> fatty acid & glycerol (via lipases)

FATTY ACID --> fatty acyl-coA
via fatty acid CoA synthetase

carnitine carries fatty acyl-CoA into mitochondria

fatty acyl-CoA --> beta oxidation

GLYCEROL (IN LIVER)
glycerol --> glycerol 3-phosphate
(via glycerol kinase)

glycerol 3-phosphate -> DHAP

DHAP can go into (1) energy via glycolysis or (2) glucose via gluconeogenesis

glycerol also can be used for triglyceride synthesis in any tissue

4

liver-specific enzyme for energy generation & glucose synthesis

glycerol kinase
(converts glycerol into glycerol 3 phoshpate)

glycerol 3-phosphate -> DHAP -> either glycolysis or gluconeogenesis

ONLY in liver.

5

acetyl-CoA carboxylase

first committed step in fatty acid SYNTHESIS!

acetyl-CoA --> malonyl-CoA
(acetyl-CoA carboxylase)

eventually make palmitate

occurs in cytoplasm

6

where does fatty acid oxidation occur? synthesis?

oxidation in mitochondria
synthesis in cytoplasm

7

fatty acid synthesis movement from mitochondria to cytosol?

oxaloacetate + acetylCoA --> citrate

citrate shuttled out

converted into oxaloacetate + acetylCoA again (via ATP citrate lyase)

acetyl-CoA --> malonyl CoA--> fatty acid

oxaloacetate --> malate --> pyruvate, back into mito

8

which is the only organ that can use glycerol as energy source?

LIVER

9

how do adipocytes make glycerol for triglyceride synthesis?

synthesizes glycerol phosphate from DHAP

10

nail clubbing suggests? nail spooning [koilonychia] suggests

clubbing: PROLONGED hypoxia

associated w/ large-cell lung cancer, TB, CF, suppurative lung disease: empyema, bronchiectasis, chronic lung abscesses

(not asthma, bc brief, episodic?)

spooning: Fe2+ deficiency anemia

11

nail clubbing:

drumstick appearance, flattening of nail folds, shininess of nail and distal portion of finger.

pressing of nail: spongy, fluctuant (unstable) sensation --> softening of nail beds

12

potential pathophysiology of digital clubbing

failure of platelet precursors to fragment completely within pulmonary circulation

increased peripheral megakaryocytes & platelet clumps --> impact finger & toe --> release PDGF and VEGF --> increased fibrovascular proliferation --> clubbing!

also, elevated levels of prostaglandin E2 implicated.

13

c-ANCA targets

lysosomal enzymes

wegners: granulomatosis w/ polyangiitis

14

wegner's (granulomatosis w/ polyangiitis)

what's involved (3)

necrotizing granulomatous vasculitis

1. upper respiratory: ear, nose, sinus, throat: chronic sinusitis, mucosal ulceration (due to mucosal granulomas that later ulcerate)

2. pulmonary symptoms: cough/hemoptysis, focal necrotizing granuloma in lung, can coalesce and undergo cavitation

3. renal disease: RPGN: crescentic

15

RPGN due to wegner's differs bc

pauci-immune.

RPGN 1: immunoglobulin against basement membrane
RPGN 2: immune complex mediated

16

nephritic 2-3 days after upper respiratory infection? nephritic 2-3 wks after URI?

2-3 days: IgA nephropathy

2-3 wks: PSGN: postinfectious strep glomerulonephritis

A is earlier

17

indirect jaundice post-stress (i.e. hiking, fasting)

gilbert syndrome! weak UDP-glucoronyl-transferase. usu not a big deal, unless stressed.

18

normal serum total bilirubin

.2-1 mg/ml
< 0.2mg direct bilirubin

19

which TB virulence factor allows for intracellular bacterial proliferation

sulfatide

20

horseshoe nuclei

langhan's giant cells

21

classic locations for disseminated TB

-basal meninges (tuberculous meningitis
-lumbar spine (Pott disease)
-psoas muscle (psoas abscess)
-serous membranes like pericardium and pleura

22

disseminate TB vs milary

milliary -> extreme form; small scattered seed-like foci of infection throughout body.

23

preventative measure for all kidney stones?

drink fluids
(most stones result from supersaturation)

24

low calcium diet on Ca2+ kidney stone formation?

INCREASES risk.

serum Ca2+ is low, compensatory increase in intestinal Ca2+ absorption and Ca2+ release from bone --> increase risk of stone formation

25

high protein diet on kidney stone formation?

increases risk.

increases body's acid load, stimulate calcium release from bones & Ca2+ excretion into urine.

recommend low protein diet for individuals w/ calcium and uric acid stones

26

high dietary Na+ on kidney stone formation?

increased Ca2+ release from bone.

recommend low Na+ diet

27

recommendation for patients w/ calcium stones and hyperoxaluria?

pyridoxine. B6 decreases endogenous oxaloacetate formation --> less stone

28

difficulty abducting right arm past horizontal position & prominence of scapular angle

serratus anterior
long thoracic n.

likely injured during masectomy

past horizontal abduction --> need seratus anterior to rotate glenoid cavity superiorly.

29

which structures can be damaged in thyroidectomy (2)

1. recurrent laryngeal, when ligate inferior thyroid
2. superior laryngeal, when ligate superior thyroid artery.

30

anterior dislocation of shoulder OR fracture of neck of humerus can injure..

axillary n. delt & teres minor & sensation to upper lateral arm

31

stretch between head and shoulder injures..

upper trunk of brachial plexus. erb's palsy

damaged musculocutaneous & suprascapular
-- shoulder adducted, arm pronated, elbow extended

32

where does clavicular fracture typically occur

middle 1/3rd, due to strength of ligamentous structures at either end.

33

first infection w/ VZV is called? reactivation is called? spread via?

spread via respiratory secretions

1st infxn: varicella, chicken pox

reactivation: herpes zoster (shingles)

34

presentation of herpes zoster (reactivation)

1st. burning and/or pain unilaterally in dermatome.

2-3 days: erythematous maculopapular rash in affected dermatome.

papule transform into vesicles that later coalesce.

rupture of vesicles -> ulcers that crust. CONTAGIOUS until lesions are DRY.

35

skin biopsy of herpes zoster infection

intranuclear inclusions in keratinocytes & multinucleated giant cells. (positive Tzanck)

acantholysis (loss of intercellular connections) & intraepidermal vesicles

dermal inflammatory infiltration and leukocytoclastic vasculitis may be present.

36

acantholysis forming suprabasal blisters -->

pemphigus vulgaris
IF: IgG deposits in reticular pattern around keratinocytes.
Ab target is desmoglein 3

37

dermatitis herpetiformis

pruritic grouped vesicles on extensor surfaces.

light micropscopy: accumulations of neutrophils on tips of dermal papillae

38

verruca vulgaris

WARTS like in HPV infection

39

skin biopsy of molluscum contagiosum

pox virus

-- eosinophillic cytoplasmic inclusions.

40

definition of GI ulcer (vs. erosion)

breaches of alimentary tract mucosa that extend THROUGH muscularis mucosae --> into submucosa or beyond

41

gastric ulcers & risk of malignancy?

can frequently be malignant in nature; associated w/ poorly defined excavated ulcer bordered by irregular heaped-up mucosa

(vs. duodenal ulcer, usu not malignancy-related)

42

duodenal ulcers & risk of malignancy?

not associated!

43

esophageal ulcer & risk of malignancy

both associated!

(1) esophageal adenocarcinoma-- associated w/ ulcerated exophytic lesion at GE-junction)

(2) squamous cell carcinoma--associated w/ plaque-like thickening of mucosa that may eventually excavate & ulcerate

44

colon ulcer & risk of malignancy?

associated!

distal colon: annular lesions w/ "napkin-ring" constriction of bowel, w/ heaped up edges & ulcerated central region.

also, ulcerative colitis generally increased risk of colorectal cancer.

45

rx for trigeminal neuralgia

carbamazepine (increase Na inactivation)

painful episodes can last for months! unclear pathogenesis

46

side effect of carbamazepine

aplastic anemia & agranulocytosis

47

haloperidol can be given for
(4)

schizophrenia, acute psychoses, acute mania, tourette

48

how to avoid confounding

confounding: confusion of two supposedly causal variables, such that part/all of observed effect thought to be due to one variable is actually due to other.

deal by matching on possible confounders: age, race

49

selection bias

choosing groups that reflect general population

50

which muscles of mastication close jaw? open?

close: masseter, medial pterygoid, temporalis

open: lateral pterygoid

51

what leaves through foramen ovale (4)?

V3 of trigeminal
lesser petrosal nerve
accessory meningeal artery
& emissary veins

52

what leaves through foramen spinosum (3)?

meningeal/recurrent branch of V3
middle meningeal artery
middle meningeal vein

53

foramen lacerum

carotid canal just above this.
-meningeal branch of ascending pharyngeal artery.
-artery & n. of pterygoid canal.

otherwise, occluded by cartilage

54

jugular foramen

-CN IX, X, XI,
-inferior petrosal and signoid sinus
-posterior meningeal artery

55

exit points for trigeminal n. branches (3)

standing room only

superior orbital fissure, foramen rotundum, foramen ovale

(not spinosum!)

56

presentation of arsenic poisioning?

arsenic containing insecticide.

GI symptoms: nausea, vomiting, abdominal pain, diarrhea. decreased level of consciousness, hypotension, tahycardia.

GARLIC ODOR in breath
MEES lines: fingernails w/ white lines

rx: dimercaprol or succimer.

displaces arsenic ions from sulhydryl groups of enzymes.

dimercaprol itself = toxic (nephrotoxic & HTN)

57

dimercaprol / succimer use (3)? mechanism?

displaces ions from sulhydryl groups of enzymes.

use for mercury, arsenic, gold, lead

58

rx for acute lead or mercury posioning?

choice: CaNa2-EDTA

59

cyanide poisioning presentation? rx (3)

presentation: almond scented breath, trismus, apnea

rx: (1) amyl nitrite (2) sodium thiosulfate (3) hydroxocobalamin

(1) nitrite: forms methemoglobin, binds to cyanide ions (forming nontoxic cyanomethemoglobin) --> prevents cyanide binding to mitochondrial enzymes

(2) thiosulfate: sulfur donor, increase thiocyanate for excretion

(3) hydroxocobalamin: bind to CN and excrete in urine

60

deferoxamine

rx: iron poisioning. facilitates urine excretion

61

rx for methemoglobinemia

methylene blue. reducing agent, converts iron in heme form Fe3+ to Fe2+

62

lyonization

process of randomly inactivating an X chromosome in normal females --> heterochromatin -- Barr body at periphery of nucleus on micropscopy.

all human females -> mosaics of X-chromosome (methylation of cytosine -> methycytosine)

63

why do RBCs make 2,3 BPG?

made in glycolysis.

normally:
glucose >>> 1,3 bisphosphoglycerate --> 3phosphoglycerate (1 ATP made) >>>> pyruvate.

in RBC, will convert 1,3 bisphosphoglycerate --> 2,3 bisphosphoglycerate (via a mutase) --> 3 phosphoglycerate >>> pyruvate

basically sacrifice making ATP, in order to make 2,3 DPG. important in reducing hemoglobins affinity for oxygen for delivery to peripheral tissue!

64

varicose veins

dilated tortuous veins that predominately involved superficial veins of leg.

risk factors: chronically increased lower-extremity venous pressure: long periods of standing, >50y/o, multiple pregs. genetic defects that affect venous wall/valvular integrity.

65

repercussions of varicose veins?

prolonged increase in intraluminal pressure results in loss of vessel-wall tensile strength. result in venous dilation --> causing veins to fail. resulting backflow exacerbates venous HTN --> worse valve competency.

complications: painful superficial thromboses, stasis dermatitis, skin ULCERATION (medial malleolus), poor wound healing, superficial infection.

66

claudication usu associated w/

pain & weakness associated w/ exertion.

due to peripheral artery disease.

67

phlegmasia alba dolens

painful white leg, "milk leg"

consequence of iliofemoral venous thrombosis in peripartum women.

pregnancy disposes to deep vein thrombosis due to pressure of uterus on deep pelvic veins --> stasis. also, hypercoagulable.

68

location of varicose veins

SUPERFICIAL venous system. not deep. less associated w/ thromboembolism & PE.

69

describe giardia morphology? most important in preventing it in GI system?

pear-shaped, bilaterally symetric organism. 4 pairs of flagella. 2 nuclei.

IgA helps prevent & clear infection. impair adherence.

70

how do eosinophils kill helminth larvae?

antibody dependent cellular cytotoxicity (ADCC). involves major basic protein.

71

familial syndrome associated w/ bronchiectasis?

kartagener's syndrome. immotile cilia due to dyenin arm defect.

infertility, recurrent sinusitis, and bronchietasis

72

most common congenital upper limb deformity. 2nd most?

most common: synfactyly -- failure of digits to separate

2nd: constriction band syndrome: interrupts fetal blood supple to distal limbs, causes amputation of fingers/toes

73

osler-weber-rendu disease aka

hereditary hemmorhagic telangiectasia

74

increased bleeding time and PTT (normal PT) suggests?

von willebrand disease
1. BT bc binds to platelets
2. PTT bc stabilizes/carries factor VII

absence of vWF --> functional factor VIII and platelet deficiency.

factor VII deficiency itself will NOT affect bleeding time.

(aka factor VII needs vWF, but vWF does not need factor VII)

if bleeding time is up, MUST mean there is a platelet issue

75

inheritence of von willebrand disease

autosomal DOMINANT w/ variable penetrance

most common heritable bleeding disorder.

76

DIC elevates

bleeding time, PT, and PTT (consumptive).

also elevated d-dimers
(degradation product of cross-linked fibrin)

77

factor XIII

transglutaminase. crosslinks fibrin polymers. STABILIZE clots.

deficiency: causes delayed bleeding, but does NOT prolong bleeding time, PT, or PTT.

78

why is amphotericin so terrible

binds cell membrane cholesterol

has higher affinity for ergosterol than cholesterol, but does affect cholesterol a little.

main: nephrotoxic, hypomagnesium, hypokalemia.

main toxicity:
1. acute infusion related reaction
- chills, fever, rigor, hypotension
- antipyretics & antihistamine can help

2. dose-dependent nephrotoxicity
-bc decreases GFR

3. electrolyte abnormalities
- hypomagnesemia and hypokalemia

4. anemia
- due to suppressed EPO synthesis

5. thrombophlebitis
- at site of injection

79

oxidase +, comma shaped, gram negative bacteria (3). how are they unique?

1. camplyobacter jejuni
- grows in 42 C
2. vibrio cholera
- grows in alkaline conditions
3. helicobacter pylori
- produces ureas

[pseudomonas is also oxidase +, but is a rod)

80

which 2 bacteria increase cAMP in intestine?

-ETEC (heat labile toxin)
-vibrio cholera

81

when should the neural tube close

4th week of fetal development

82

failure of neural tube closure increases 2 things in amniotic fluid

AFP and acetylcholinesterase

83

duodenal atresia occurs due to

abnormal apoptosis. duodenal lumen fails to recanalize

84

adverse effects of L-DOPA on brain

anxiety and agitation

also insomnia, confusion, delusions, hallucinations

85

test for supraspinatus pathology?

empty-can supraspinatus test.

simultaneous abduction and flexion of arm at shoulder & apply force downwards

86

long head of biceps brachii? short head?

long head: passes through glenohumeral joint to insert on supraglenoid tubercle of scapula.

short-head on coracoid

87

levator scapulae inserts on..

superomedial border of scapula and on tranverse processes of C1 - C4

88

primary biliary cirrhosis

chronic liver disease.

characterized by autoimmune destruction of intrahepatic bile ducts & cholestasis

usu middle age women, insiduous onset.

pruritus is first symptom, fatigue.

physical exam: hepatosplenomegaly, xanthomatous lesions of eyelind or in skin / tendons

lab: elevated ALP, cholesterol, and IgM

associated w/ autoimmune diseases

89

describe changes w/ skin aging.

aging of human skin by 30-35. gradual thinning, reduction in subcutaneous fat, blood vessels, hair follicles, sweat ducts, & sebaceous gland.

decreased dermal collagen & elastic fibers

90

wrinkles due to..

reduced synthesis of collagen fibrils.

loss of intrinsic reticular supoprt -- inelastic skin sags and demonstrates wrinkles

91

severe triglyceridemia can cause...

pancreatitis

92

2 mechanisms of fibrates

(1) activate PPAR-alpha
(2) increased LPL activity --> triglyceride clearance

93

how does PTH activate osteoclasts (3)

stimulate osteoblasts to (1) express RANK-L (2) secrete M-CSF

also decrease osteoprotegrin release (decoy receptor for RANK-L)

94

thyroid hormone on bone formation

t3 increases bone turnover by mainly increasing OSTEOCLASTIC RESORPTION

(reason why patients w/ thyrotoxicosis have mild hypercalcemia)

95

where is ventillation highest? perfusion? V/Q ratio?

BOTH ventilation & perfusion higher at BASE

V/Q RATIO greater at APEX

-ventillation greater at base b/c alveoli are less distended, more compliant (weight of lung)
-perfusion greater at base bc of gravity

perfusion GREATLY increases as move to base. ventilation increases slightly

96

why do fibrates increase cholesterol stone in gallbladder?

inhibit 7-alpha-hydroxylase, increased cholesterol in bile -- ppt out

97

first step in cholesterol synthesis

via thiolase
condense two acetyl-CoA into acetoacetyl-CoA --> substrate for HMG-CoA reductase

98

which hepatitis viruses transmitted fecal-oral?

NAKED ones. hep A and hep E

99

hepatitis E is concerning in what population

high mortality rate in pregnant women.

most people --> self-limited. not associated w/ chronic liver disease OR carrier state.

100

gait abnormality & urinary incontenience. LATER progresses to progressive dementia and emotional blunting

NORMAL PRESSURE HYDROCEPHALUS.
- wacky, wobbly, wet

gradual diminshed reabsorptive capacity of arachnoid villi.

(distinguish from alzheimers due to the order of symptoms!)

sometimes reversible w/ relief of CSF volume

101

agenesis

absent organ due to absent primordial tissue

102

aplasia

absent organ DESPITE presence of primordial tissue

103

hypoplasia

incomplete organ development ; primordial tissue present

104

deformation

extrinsic deformation occurs AFTER embryonic period

uterine pressure on fetus in breech position --> congenital hip dislocation. clubbed feet.

105

disruption

secondary breakdown of previous normal tissue or structure (i.e. amniotic band syndrome -- amniotic bands compress/ampute fetal limbs

106

malformation

instrinsic disruption; during embryonic period (weeks 3-8)

i.e. holoprosencephaly, congenital heart disease, anencephaly, polydactyly, syndactyly

107

sequence

abnormalities resulting form a single primary embryological event (i.e. oligohydramniosis --> potter sequence)

108

holoprosencephaly

MALFORMATION: primary defect in cells or tissues that form an organ. division of prosencephalon happens during 5th wk of embryonic period.

associated w/ patau, edwards, and fetal alcohol syndrome

109

most calcium stones result from what serum state / urine state

normocalcemia, hypercalciuria

(usu idiopathic hypercalciuria)

110

what can cause hyperoxaluria?

diet high in oxaloacetate: chocolate, nuts, spinach

also, diets low in Ca2+ makes more free oxaloacetate for absorption and subsequent renal excretion (occurs in crohn's disease & other intestinal malabsorption)

111

what can cause hyperuricosuria?

high protein diet, large amounts of purines metabolized into uric acid.

112

morning stiffness in osteoarthritis

happens! just shorter than in rheumatoid arthritis (~10-15min)

RA: can last hours

113

most common cause of epiglottitis?

haemophilus influenza B:

drooling, dysphagia, difficulty breathing, fever, cherry red epliglotis

inspiratory stridor (narrowed larynx)

114

cerebellar tumor in child w/ primitive cells?

medulloblastoma! primitive neuroectoderm