test #19 4.9 Flashcards Preview

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Flashcards in test #19 4.9 Deck (97)
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1
Q

osteocytes (trapped osteoblasts) are connected to one another via..

A

cytoplasmic extension travel from lacunae through canaliculi, connect via GAP JUNCTION. send signals & exchange nutrients & waste products

2
Q

tight junctions

A

zona occludens (1st component of junctional compelx)

3
Q

intermediate junctions

A

zona adherens (2nd component of junctional complex)

4
Q

desmosomes

A

3rd component of junctional complex

5
Q

maternal blood types A and B often have what type of anti-B and anti-A Abs (respectively)? what about type O?

A

A and B have IgM (doesn’t cross placenta).

type O have predominately IgG anti-A and anti-B type (can cross placenta & cause hemolytic disease of newborn in 3% of pregnancies). can happen w/ 1st pregnancy.

6
Q

in what maternal blood type do we worry about erythroblastosis fetalis and hemolytic disease of newborn?

A

type O moms with type B or A babies. bc they make anti-B or A IgG.

7
Q

common carotids from what aortic arch?

A

3rd

8
Q

1st branchial/pharyngeal arch? associated w/ which n.

A

associated w/ trigeminal n.

neural crest cells make: Maxilla, zygoma, Mandible, vomer, palatine, incus, Malleus. (M’s)

mesoderm: muscles of mastication (temporalis, medial / lateral pterygoid, masseter) anterior belly of digastric, mylohyoid, tensor tympani, tensor veli palatini.

9
Q

embryological origin of branchial arches (2)

A

muscle & arteries = mesoderm.

bone = neural crest cells

10
Q

2nd branchial/pharyngeal arch? associated n?

A

associated w/ facial n.

neural crest: styloid process, lesser horn of hyoid, stapes.

mesodern: muscles of facial expression, stylohyoid, stapedius, posterior belly of digastric

11
Q

4th and 6th arch

A

make up cartilaginous structures of larynx.

12
Q

3 most common causes of metabolic alkalosis

A
  1. LOSS OF H+ from body: vomiting, nasogastric suction. loose HCl in gastric secretion, causes serum Cl- to decrease

(leads to DECREASED urinary Cl-, t help. SALINE-RESISTANT

13
Q

bilateral lesions in mamillary bodies & periaqueductal grey area in hospital (in alcoholic)

A

due to glucose infusion w/o thiamine in thiamine deficient person. PDH needs thiamine!

14
Q

wernicke encephalopathy

A

(1) opthalmoplegia: horizontal nystagmus, bilateral abducens palsy, complete opthalmoplegia
(2) ataxia: degeneration of all layers of cortex
(3) confusion, apathy, inattentiveness, disorientation: from encephalopathy.

characterestic hemorrhage into mamillary body

15
Q

infuse glucose + ___ in alcoholics & bad diet

A

THIAMINE (B1)

16
Q

heterophile negative mononucleosis (3)?

A

CMV, HHV-6, toxoplasmosis

17
Q

coxsackie A causes (2)

A

(1) asceptic meningitis and (2) herpangina in children

18
Q

nifedipine can..

A

elevate capillary hydrostatic pressure –> edema

19
Q

common causes of lymphatic obstruction (3)

A

(1) filariasis,(2) invasive malignancy, (3) iatrogenic (surgical lymph node dissection & radiation therapy)

20
Q

downstream signaling targets of insulin

A

generally: insulin receptor substrates (IRS), leading to acrivation of a PROTEIN PHOSPHATASE.

DEPHOSPHORYLATES GLYCOGEN SYNTHASE (1. activates glycogen synthase to promote glycogen synthesis & 2. dephosphorylates fructose 1,6 bisphosphatase to inactivate & block gluconeogenesis)

21
Q

facial n. constituents.. (4)

A
  1. motor to facial muscles
  2. parasympathetic to lacrimal, submandibular, sublingual salivary glands.
  3. special afferent fibers for taste (ant 2/3)
  4. somatic afferents from pinna and external auditory canal

bell’s palsy: unilateral face paralysis (impaired eye closure, eyebrow sagging, inability to smile/frown on affected side, loss of nasolabial fold, mouth drawn to non-affected side. can have: decreased tearing, hyperacusis, loss of taste sensation over anterior 2/3rd of tongue

22
Q

geniculate ganglion

A

parasympathetic ganglion for submandibular, sublingual, and lacrimal glands. innervated by facial n.

23
Q

motor in trigeminal?

A

V3 – muscles of mastication and tensor tympani

24
Q

filtration fraction

A

fraction of PLASMA entering the kidney that filters into renal tubular lumen.

FF = GFR/(1-Hct x RBF)

25
Q

in gastrectomy, must supplement with

A

B12 (water soluble vitamin)

26
Q

role of pepsin in digestion

A

activated by HCl, cleaves polypeptides at sites of aromatic amino acids. helpful, but not required for protein digestion.

27
Q

premature ovarian failure age? mean age of menopause in US? marker?

A

ovarial failure before 35. mean age of menopause in US: 52. HIGH FSH (above 30uL)

28
Q

urinary 17-ketosteroids

A

measure adrenal androgens (DHEA, DHEA-S, 4androstenedione)

29
Q

chronic lymphedema is a risk factor for..

A

development of cutaneous angiosarcoma (St

30
Q

chronic lymphedema is a risk factor for..

A

cutaneous (lymph)angiosarcoma.

classic: radical masectomy w/ axillary lymph node dissection –> multiple firm violaceous nodules

31
Q

prognosis of angiosarcoma?

A

POOR, tumor usu wide spread by diagnosis.

32
Q

histopathology of angiosarcoma

A

infiltration of dermis w/ slit-like abnormal vascular spaces

33
Q

breast cancer is most likely to metastasize to..

A

bone, liver, lung

34
Q

stewart-treves syndrome

A

chronic lymphedema —> angiosarcoma

35
Q

presentation of hepatitis A virus

A

most often silent “anicteric”. sometimes: acute, self-limited illness characterized by jaundice, malaise, fatigue, anorexia, N/V, RUQ pain, or AVERSION TO SMOKING.

infxn usu more severe in adults

36
Q

infection involving central venous catheters are often originate from…

A

patient’s skin flora OR bacteria on hands of HCW

gram positive cocci – coag neg staph & staph aureus

37
Q

steps to reduce CVC infxn? what’s not needed?

A

most important: hand hygiene – washing & gloves. chlorhexidine for skin disinfection, avoid femoral insertion site. remove when no longer needed.

NOT NEEDED: TOPICAL antibiotics not needed (increase resistance & candida prolif), ORAL antibio, routine replacement.

38
Q

process of type I collagen synthesis

A

in ER:
(1) HYDROXYLATE select pro & lys residue [vit C dep]
(2) GLYCOSYLATE select lys residue w/ galactose & glucose
(3) assemble into procollagen TRIPLE helix
golgi –> secreted

outside:
(1) terminal propeptides (INTRAchain disulfides) cleaved N- and C- procollagen peptidases —> TROPOCOLLAGEN.
(2) collagen fibrils spontaneously assemble
(3) LYSYL OXIDASE (Cu2+) covalently cross-links

39
Q

two possible enzyme deficiences in Ehlers-Danlos

A

(1) lysyl-hydroxlase: hydroxylate single chain.

(2) procollagen peptidase: cleave terminal chains extracellularly, allowing for tropocollagen full helix formation.

40
Q

distinguishing Ehlers-Danlos due to (1) lysyl hydroxylase deficience or (2) propeptidase deficiency

A

(1) lysyl hydroxylase: kyphoscoliosis & ocular fragility: have less hydroxylysine in collagenous tissue.
(2) procollagen peptidase: disulfide-rich globular domain.

41
Q

choroid plexus in which ventricles

A

lateral & 4th

42
Q

causes of congenital noncommunicating hydrocephalous (3)

A

aqueductal stenosis, arnold-chiari, dandy-walker

43
Q

high NADH w/ low glucose?

A

suggests another fuel is being used by body. i.e. ethanol.

ethanol –> acetaldehyde –> acetate. produces 2 NADH.

high NADH/NAD+ ratio. promotes pyruvate to lactate, oxaloacetate to malate. inhibits gluconeogenesis. HYPOGLYCEMIA.

44
Q

causes of lactic acidosis

A
  1. enhanced metabolic rate (seizure/exercise)
  2. reduced oxygen delivery (cardiac/pulmonary failure, shock, tissue infarction –> decreased oxidative phosphorylation.
  3. diminished lactate catabolism (hepatic failure or hypoperfusion.
  4. decreased oxygen utilization (cyanide posioning)
  5. enzymatic defects in glycogenolysis / gluconeogenesis
45
Q

most dependent regions of lung in supine individual (2) i.e. sites for aspiration when laying down?

A

(1) superior regions of lower lobes.

(2) posterior regions of upper lobes.

46
Q

culprits in aspiration pnemonia?

A

anaerobics inhabitants of upper airway: peptostreptococcus, bacteroides, prevotella, fusobacterium.

47
Q

4 loop diuretics

A

furosemide, torsemide, bumetanide, ethacrynic acid (greatest risk of ototoxicity)

48
Q

triamterene & amiloride

A

blocks ENac.

49
Q

common ototoxic agents?

A

aminoglycosides, salicylates, cisplatin

50
Q

busipirone

A

5-HT1A agonist w/ minimal hypnotic, sedative, euphoric, muscle relaxant effects.

good for GENERALIZED anxiety disorder. not for more specific ones.

low abuse potential

51
Q

anti-anxiety rx in patient w/ history of benzo abuse

A

busipirone! low abuse potential.

52
Q

acutely injured child, suspected child abuse. first thing done?

A

call child protective services: DOCUMENT & get social work involved.

have THEM evaluate / intervene w/ parents and see what’s up.

53
Q

best auscultory indicator of mitral stenosis severity? why?

A

S2-to-OS time. shorter interval, more SEVERE stenosis.

OS: tensing of mitral valve leaflets after cusps have completed opening. (1) more thickened/fibrotic –> earlier tensing.

also, A2-OS interval inversely correlates w/ (2) left atrial pressure.

54
Q

cladribine? rx for?

A

purine analog, resistant to degradation by adenosine deaminase. urx for hairy cell leukemia.

55
Q

cyclophosphamide

A

alklyating agent & cross-link, must be activated by P450.

56
Q

lomustine

A

nitrosurea. good CNS penetration. alkylating agent & crossbridge. nonenzymatic hydroxlation to be active.

57
Q

dacarbazine

A

cell-cycle nonspecific methylating agent. requires enzymatic activation

58
Q

cisplatin. prevent nephrotoxicity w/?

A

platinum-containing chemotherapeutic. hydrated to be cytotoxic. prevent nephrotoxicity w/ amofostine (free radical scavenger) and Cl- diuresis.

59
Q

methotrexate

A

folic acid analogue, inhibits dihydrofolate reductase.

60
Q

mercaptopurine

A

purine analogue. activated by HGPRT (guanine –> GMP and hypoxanthine –> IMP) and metabolised by xanthine oxidase. (toxicity increases w/ allopurinol)

61
Q

3 clases of antimetabolites?

A

(1) folate antagonist (2) purine analogue (3) pyrmidine analogue

62
Q

rx for absence seizures

A

ethosuximide & valproate

63
Q

tonic clonic & absence seizures

A

valproate works on both

64
Q

ethosuximide works by..

A

blocking thalamic Ca2+ channels

65
Q

drug of choice for complex partial seizure? feared side effects?

A

carbamazepine: fear agranulocytosis and aplastic anemia7h

66
Q

why do opiods cause constipation? miosis?

A

bind to mu-opioid receptors in GI tract, cause decreased secretions and gastric motility. miosis– activation of parasympathetics

67
Q

most common and unpleasant side effect of opiod use?

A

nausea. stimulate chemoreceptor trigger zone leading to emesis. tolerance will develop

68
Q

how do thiazides (chlorthiadone, hydrochlorothiazide) cause hypercalcemia?

A

block Na+ Cl- symporter apically. less intracellular Na+. stimulates basolateral Na+/Ca2+ exchanger, bring more Na+ in, Ca2+ out.

less intracellular Ca2+ –> more luminal Ca2+ absorption in DCT. also, increase Ca2+ in PCT due to volume depletion may occur.

69
Q

thiazide and thiazide-like diuretics

A

chlorthiadone, hydrochlorothiazide, indapamide, metolazone (diff potency, bioavailability, half-life)

70
Q

C. diff toxin affects

A

toxin A and B, both internalized.

toxin A: neutrophil chemoattractant, mucosal inflammation loss of water into gut mucosa, results in mucosal death.

toxin B: actin depolymerization, loss of cellular cytokeleton, death and necrosis

71
Q

drugs associated w/ mitochondrial toxicity?

A

cyanide, nucleoside reverse transcriptase inhibitors (nRTIS

72
Q

lecithinase alpha toxin released by?

A

C. perfringens. watery diarrhea, gas gangrene.

73
Q

how does antagonism of muscarinic lead to flushed cheeks?

A

inhibition of eccrine sweat glands –> fever —> compensatory cutaneous vasodilation.

74
Q

diphenhydramine? side effects?

A

H1-receptor antagonist, has ANTI-CHOLINERGIC effects

75
Q

H1 receptors cause..

A

vascular permeability and bronchoconstriction

76
Q

5 drugs w/ antimuscarinic effects

A

atropine, TCA’s (amitriptyline), H1 receptor antagonist (diphenhydramide) neuroleptics, antiparkinsonian drugs

77
Q

venous drainage from lower limb

A

from superficial veins through perforating veins into deep veins of extremities. deep veins –> inferior vena cava.

incompentence of venous valves : varicose veins

78
Q

stasis dermatitis

A

chronic venous insufficency (i.e. from varicose veins can lead to) —> erythema and scaling w/ progressive dermal fibrosis & hyperpigmentation

79
Q

paroxysmal nocturnal hemoglobinura presents with.. (3). explain misnomer.

A

(1) hemolytic anemia (2) hypercoagulable state (3) decreased blood count.

hemolysis only appears to be nocturnal bc urine collects & concentrates overnight, causing dramatic color change in morning. can technically occur all day.

80
Q

pathophysiology in PNH (paroxysmal nocturnal hemoglobinuria)

A

mutation in PIG-A (codes for GPI-anchor) needed for attachment of CD55 CD59. cell surface markers that inactivate complement. results in hemoylsis and thrombisis (COD)

81
Q

deficiency of CD55 and CD59

A

PAROXYSMAL NOCTURNAL HEMOGLOBINURIA. normally. inactivate complement on RBCs. not expressed on surface in PNH.

82
Q

achondroplasia inheritance

A

85% sporadic, associated w/ advanced paternal age. 15% AUTOSOMAL DOMINANT.

if family ask about inheritance, since achondroplasia is relatively rare, the 85% chance of sporadic mutation does not significantly factor into the 50% risk of inheritance (w/ inherited mutation)

83
Q

PCOS pathophysiology

A

unnknown. persistently elevated estrogen, androgen, and LH.

hyperandrogenism, chronic anovulation, oligomenorrhea, and multiple ovarian cysts.

often have obesity, insulin resistance, and dyslipidemia.

present w/ enlarged ovaries w/ thickened endometrium (risk for endometrial hyperplasia)

84
Q

rx for PCOS (stein-leventhal syndrome)

A

clomiphene: SERM; prevents negative feedback inhibition on hypothalamus by circulating estrogen. increases FSH and LH –> ovulation

85
Q

unopposed elevated estrogen in PCOS increases risk for…? specific rx for this?

A

endometrial hyperplasia –> endometrial carcinoma. rx: progesterone!

86
Q

clomiphene

A

SERM. prevents negative feedback inhibition on hypothalamus by circulating estrogens. (increase FSH and LH). for ovulation.

87
Q

why are lower lung fields most affected by panacinar emphysema?

A

more perfusion, greater neutrophil invasion, more elastase.

88
Q

coffee ground emesis

A

blood in vomitus that has been exposed to gastric acid. (colour from oxidation of heme iron).

89
Q

body can sustain normal BP and CO with how much blood loss? what occurs when more is lost?

A

10%. more than this –> sympathetic nervous system activated: constriction of arteriole & venous beds & stimulation of heart.

constrict arterioles: increase total peripheral resistance, maintain end organ pressure. shunt blood from extremities.

constrict venous: increase blood return to heart, maintain PRELOAD

stimulate heart: increased contractility and HR.

90
Q

most important intervention in hypovolemic shock>

A

even before identify/eliminate source of bleeding is:

RAPID INFUSION OF BLOOD AND CRYSTALLOID SOLUTION like normal saline. increase intravascular volume & ventricular preload –> increases end-diastolic sarcomere length – > increased stroke volume and cardiac output

91
Q

passive-aggressive

A

expressing aggression towards others by passively refusing to meet their needs. i.e. missing appointments. act out hostile feelings in a non-confrontational manner.

92
Q

acting out

A

immature defense that involves expressing unconscious wishes or impulses through actions. i.e. temper tantrum

93
Q

isolation

A

coping mechanism, separation of an idea and its accompanying emotions. i.e. discussing war in nonemotional terms

94
Q

undoing

A

symbolically nullifying an unacceptable or guilt-proviking throught, idea, feeling, by confession / atonement.

95
Q

extensive cerebellar purkinje cell degeneration w/ lung cancer?

A

immune-mediated paraneoplastic cerebellar degeneration. associated w/ lung, breast, ovary, uterus, lymphoma cancer.

96
Q

antibodies associated with paraneoplastic cerebellar degeneration

A

anti-yo: ovary/breast.
anti-P/Q: lung
anti-Hu: lung

anti-tumor Ab cross-react w/ neurons, degeneration of cerebellum. present w/ limb / truncal ataxia etc.

97
Q

paraneoplastic

A

associated w/ systemic cancer, but NOT due to metastasis, metabolic defects, nutritional deficency, infxn, coagulopathy, or side effects of therapy.

associated w/ substances produced by tumor cell (i.e. induction of autoimmune phenomena [cerebellar degeneration], or hormone-like substances [ACTH, PTHrP]