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Flashcards in 2015.04.02 Deck (84)
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1
Q

Treatment of H. pylori peptic ulcers

A

2 antibiotics (metronidazole, tetracyclin, amoxicillin, or clarithromycin)

AND

Adjunctive agent (Proton pump inhibitor and/or bismuth)

2
Q

Ranitidine

A

H2 blocker used for treating peptic ulcer disease

3
Q

Sucralfate

A

Binds to base of mucosal ulcers, protecting against gastic acid

4
Q

Misoprostol

A

Prostaglandin E1 analog used to prevent NSAID-induced ulcer disease

5
Q

Most common metastatic tumors to the brain

A

lung cancer

renal cancer

melanoma

6
Q

Clinical features of Melanoma

A

Asymmetry

Border irregularities

Color variegation

Diameter >6mm

Evolving: lesion changing in size, shape, color

7
Q

Melanoma origin

A

Malignancy of melanocytes (neural crest origin)

8
Q

Endoderm derivatives

A

structures from inner lining of primitive gut tube; thyroid follicular cells, epithelial surfaces of trachea, bronchi, lungs; liver and biliary tree; pancreas; GI and bladder epithelium

9
Q

Mesoderm derivatives

A

Dermis; bones, muscles, blood vessels, and visceral tissue

10
Q

Neuroectoderm derivatives

A

CNS, preganglionic autonomic neurons, retina, posterior pituitary

11
Q

Surface ectoderm

A

Epidermis and its appendages, mammary glands (modified sweat glands), lens of the eye, and adenhypophysis

12
Q

Chromosome 3p VHL gene

A

Sporadic and hereditary (associated with Von Hippel-Lindau disease) renal cell carcinomas

13
Q

Von Hippel-Lindau disease

A

Autosomal dominant Cerebellar hemangioblastomas, clear cell carcinomas and pheochromocytomas

Renal cell carcinoma develops in 40% of these patients

14
Q

RB anti-oncogene on Chromosome 13

A

Retinoblastoma and osteosarcoma

15
Q

NF-1 on chromosome 17

A

Neurofibromatosis type 1

16
Q

WT-1 anti-oncogene on chromosome 11

A

Wilms tumor

17
Q

Flow of CSF

A

Lateral ventricles

Interventricular foramen of Monro

3rd Ventricle

Cerebral aqueduct

4th Ventricle

Foramina of Luschka and Magendie

Subarachnoid space

Absorbed by arachnoid granulations

Enters venous sinuses

18
Q

Symmetrical enlargement of ventriculi

A

Communicating hydrocephalus - secondary to dysfunction or obliteration of subarachnoid villi

Usually sequelae of meningeal infection or subarachnoid/intraventricular hemorrhage

19
Q

Graft versus host disease

A

T-lymphocytes of donor tissue are sensitized against MHC antigens of recipient.

Skin, liver, and intestine commonly involved

20
Q

Acute/Chronic Graft Rejection

A

Host T-cells have been sensitized against graft MHC antigens.

Acute rejection manifests as vasculitis of graft vessels.

Chronic rejection leads to fibrosis of graft stroma and blood vessels

21
Q

Myasthenia gravis

A

Circulating antibodies against ACh receptors of the NMJ.

Autoantibody binding causes complement-mediated destruction of these receptors, producing weakness that most affects extraocular muscles.

Associated with thymoma/thymic hyperplasia

22
Q

Guillain-Barré syndrome

A

CD8+ lymphocyte mediated nerve fiber demyelination.

Segmental demyelination with ascending muscle weakness.

Often associated with preceding Campylobacter infection

23
Q

Polymyositis

A

CD8+ lymphocyte mediated skeletal muscle damage.

Presents with symmetric proximal muscle weakness.

24
Q

Psammoma bodies

A

round, eosinophilic, laminar structures composed of core of dense calcification with surrounding collagen-fiber bundles.

Among CNS tumors, they indicate meningioma.

Seen also in Papillary thyroid carcinoma and serous papillary ovarian adenocarcinoma

25
Q

Oligodendroglioma

A

“fried egg” appearance (nuclei with finely granular chromatin surrounded by clear cytoplasm)

26
Q

Glioblastoma multiform

A

most common primary, malignant brain tumor in adults.

“palisading” pattern of tumor cells

27
Q

Auditory Canal sensation

A

Posterior external auditory canal - Vagus nerve (small auricular branch)

Rest of the canal - CN V3

28
Q

Vasovagal Syncopal episode

A

Stimulation of vagus nerve, leading to a decrease in blood pressure and heart rate

29
Q

Chorda tympani nerve

A

Branch of facial nerve.

Middle ear innervation

Anterior 2/3 of tongue - afferent taste fibers

Efferent parasympathetic preganglionic fibers to submandibular and sublingual salivary glands.

30
Q

Prepatellar Bursitis

A

“housemaid’s knee”; repeated and prolonged kneeling

31
Q

Arginase

A

Enzyme of urea cycle that produces urea and ornithine from arginine

32
Q

Acyclovir Valacyclovir Famciclovir

A

Nucleoside analog

Antiviral drugs for Herpes Simplex Infection.

Are phosphorylated by viral thymidine kinase and can be incorporated into viral DNA chain by viral DNA polymerase, terminating DNA synthesis

33
Q

Pressure changes by AV shunts

A

Increase preload by increasing the rate and volume of blood flow back to the heart (arterial blood directly enter venous, bypassing arterioles)

Decrease afterload by routing blood directly from arterial system to venous system (decreased total peripheral resistance)

34
Q

Pathogenesis of atherosclerotic plaques

A

Locally adherent platelets, endothelial cells, and macrophages release platelet-derived growth factor (PDGF) which promotes migration of SMCs from the media into the intima and their subsequent proliferation

35
Q

Familial hypercholesterolemia

A

Autosomal dominant mutations of LDL receptor gene.

Less removal of cholesterol-containing IDL and LDL leads to accelerated atherosclerosis and early-onset CAD.

Liver is primary site of cholesterol catabolism and excretion

36
Q

Systemic mastocytosis

A

Proliferation of mast cells and increased histamine secretion.

Histamine increases production of gastric acid by parietal cells.

37
Q

Methacholine

A

Muscarinic cholinergic agonist that induces bronchial smooth muscle contraction and increased bronchial mucous production

38
Q

Pericardial tamponade triad

A

muffled heart sounds, elevated jugular venous pressure, profound hypotension 3-7 days after total ischemia (coagulative necrosis, neutrophil, lysis of CT)

39
Q

Glomerulonephritis vs. Acute rheumatic fever

A

Glomerulonephritis - prior strep pharyngeal or skin infection

ARF - prior strep pharyngitis

40
Q

Evidence of streptococcal infection

A

Anti-streptolysin

Anti-DNaseB

Anti-Hyaluronidase

41
Q

Streptococcus Pyogenes

A

Catalase-

B-hemolytic

Gram+ cocci in chains

Bacitracin sensitive

Pyrrolidonyl arylamidase (PYR) +

42
Q

Streptococcus pneumoniae

A

Catalase-

a-hemolytic

Gram+ cocci

Optochin-sensitive

Bile-soluble

43
Q

Pelvic surgeries

A

Ureters just posterior to the uterine arteries accidentally ligated and can cause hydronephrosis

44
Q

Speed of hemoglobin movement during gel electrophoresis

A

HbA > HbS >HbC

45
Q

Hemoglobin C mutation

A

missense mutation: lysine replaces glutamate in beta globin

46
Q

Hemoglobin S mutation

A

missense mutation: valine replaces glutamate

47
Q

Ecthyma gangrenosum

A

Cutaneous necrotic disease associated with Pseudomonas aeruginosa bacteremia and septicemia

48
Q

Pseudomonas aeruginosa virulence factors

A

Exotoxin A (protein synthesis inhibition)

Elastase (degrades elastin)

Phospholipase C (degrades cellular membranes)

Pyocyanin (generates ROS)

49
Q

Chronic Myeloproliferative Disorders

A

Chronic Myelogenous Leukemia

Essential thrombocytosis

Polycythemia vera

Primary myelofibrosis

50
Q

Chronic Myelogenous Leukemia

A

Philadelphia chromosome t(9:22) BCR-ABL fusion protein

51
Q

JAK2 mutation

A

Essential throbocytosis

Polycythemia vera

Primary myelofibrosis

52
Q

Ruxolitinib

A

JAK2 inhibitor

53
Q

Acute lymphocytic leukemia

A

predominantly affects children

54
Q

Acute promyelocytic leukemia

A

translocation t(15;17) leads to formation of fusion gene between PML and RARa which blocks differentiation of myeloid precursors

55
Q

Chronic Lymphocytic Leukemia

A

Lymphocytosis with “smudge cells”

Increased BCL-2 expression

56
Q

Burkitt lymphoma

A

t(8;14) and involves c-myc oncogene

Associated with EBV

“starry sky”

57
Q

Vomiting vs. Diarrhea

A

Vomitting - Leads to metabolic alkalosis due to net loss of acidic gastric secretions

Diarrhea - Normal anion gap metabolic acidosis due to loss of bicarbonate

58
Q

NItrates

A

decrease cardiac preload, cardiac work and myocardial oxygen demand by causing venodilation

treatment of angina pectoris

59
Q

Subungal splinter hemorrages

A

Splinter/flame shaped hemorrhage streaks in nail bed appear as the consequence of microemboli

Infectious endocarditis (may be progressing to subacute bacterial endocarditis) is the usual cause - detect new-onset regurgitant murmur

60
Q

Janeway lesions

A

small, macular, erythematous or hemorrhagic, nontender lesions on the palms or soles; also sign of microembolism

61
Q

Direct arteriolar vasodilators (hydralazine and minoxidil)

A

Cause significant vasodilation and low pressure which stimulate baroreceptor to activate sympathetic system - leads to increased hr, contractility and renin activity.

Usually given with sympatholytics and diuretics to counteract reflex effects.

62
Q

Buspirone

A

Selective agonist of 5HT1A receptor for treatment of generalized anxiety disorder.

Clinical response is delayed for up to 2 weeks.

63
Q

Nicotinic cholinergic receptor

A

sodium and calcium influx potassium outflux

Due to ligand binding - ACh

64
Q

Lipooligosaccharide (LOS)

A

Present on N. meningitidis; analogous to lipopolysaccharide (LPS) of enteric gram- rods

65
Q

Mycobacterial resistance to isoniazid

A

Mycobacterial catalase-peroxidase required for activation of isoniazid (inhibits mycobacterial mycolic acid synthesis)

66
Q

Mycobacterial resistance to streptomycin

A

Mutations of genes that encode ribosomal proteins are responsible for aminoglycoside resistance (Streptomycin binds bacterial 30S ribosomal subunit)

67
Q

Mycobacterial resistance to ethambutol

A

Increased activity of enzymes involved in cell wall polysaccharide synthesis

68
Q

Fluoroquinolone Resistance

A

Due to structural alteration of enzymes involved in DNA winding-unwinding.

Fluroquinolones work by inhibiting the bacterial enzyme DNA gyrase (topoisomerase II)

69
Q

Rifampin Resistance

A

Due to structural alteration of enzymes involved in RNA synthesis (DNA-dependent RNA polymerase)

Rifampin inhibits bacterial DNA-dependent RNA polymerase

70
Q

Treatment of open-angle and angle-closure glaucoma

A

Carbonic anhydrase inhibitors (decrease HCO3 and aqueous humor formation)

71
Q

Acetazolamide

A

Diuretic; Inhibits carbonic anhydrase which effectively block HCO3 reabsorption in the proximal tubules - resulting in HCO3 and water excretion

72
Q

Small Cell Carcinomas

A

evidence of neuroendocrine differentiation - neuron-specific endolase, chromogranin, synaptophysin, neurofilaments, neurosecretory granules

73
Q

Vimentin

A

intermediate filament within cells of mesenchymal origin; used for diagnosing sarcomas

74
Q

Diastolic Heart failure

A

usually due to impaired myocardial relaxation or increased intrinsic ventricular wall stiffness (decreased compliance)

Need increased LVEDP to maintain normal LVEDV and SV

75
Q

Systolic Heart Failure

A

due to decrease in ventricular contractile performance (decreased ejection fraction)

Requires increase in both LVEDP and LVEDV to improve SV

76
Q

gag gene

A

HIV structural gene that codes for nucleocapsid proteins p24 and p7

77
Q

env gene

A

HIV structural gene that codes for envelope glycoproteins gp120 and gp41

78
Q

pol gene

A

HIV structural gene that encodes for important enzymes

79
Q

tat and rev

A

HIV regulatory genes required for viral replication

80
Q

Cord Factor

A

Growth of thick, ropelike cords of mycobacterial organisms in a twisted, “serpentine” pattern

Mycoside - two mycolic acids bound to disaccharide trehalose

Correlates with virulence - inactivate neutrophils, damage mitochondria, release of TNF

81
Q

Polyene antifungals (Amphotericin B and nystatin)

A

bind ergosterol in fungal cell membrane, creating pores and causing cell lysis

82
Q

Triazoles (Ketoconazole, Fluconazole, Itraconazole, Voriconazole)

A

Inhibit ergosterol synthesis

83
Q

Echinocandins (Caspofungin and Micafungin)

A

Inhibit glucan synthesis (component of fungal cell wall)

84
Q

Pyrimidines (Flucytosine)

A

Converted to 5-fluorouracil within the fungal wall and interferes with fungal RNA and protein synthesis