Rx_HemOnc_2.28 Flashcards Preview

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Flashcards in Rx_HemOnc_2.28 Deck (14)
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1

SCID: presentation & common causes

  • profound T & B lymphocyte immunodeficiencies ==> recurrent infections by viruses, protozoa, bacteria, fungus
  • common causes
    • adenosine deaminase deficiency (AR)
      • ADA = necc. for purine nucleotide breakdown ==> build-up of deoxyadenosine triphosphate ==> toxic to rapidly proliferating cells (e.g. developing lymphs)
      • prone to Candida & PCP
    • IL-2 receptors (x-linked)

2

Biostatistical parameters:

"ability of the test to rule out disease"

"ability of test to rule in disease"

  • rule out = sensitivity
  • rule in = specificty

3

Order of locations of hematopoiesis during development

  • fetal erythropoiesis = 
    1. yolk sac (3-8 weeks)
    2. liver (6 mo.--birth)
  • infant erythropoiesis = 
    1. splean (10-28 weeks)
    2. bone marrow (18 weeks onward)

4

EBV: virus type

linear, double-stranded DNA virus

5

Active form of prednisone

  • prednisone ==> prednisolone [active form] via 11-B-hydroxysteroid dehydrogenase

6

(Neg.) nitroblue tetrazolium dye reduction ==> dx?

  • Chronic Granulomatous Disease
    • due to deficiency of nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase) ==> conversion of O2 => superoxide radicals
  • increased susceptibility to catalase (+) organisms
    • S. aureus
    • E. Coli
    • Aspergillus

7

S. aureus appearance on gram-stain

gram (+) cocci in clusters

8

Fibrinogen facilitation of platelet aggregation via...

  • interaction w/ GP IIb/IIIa <== expressed on the surgace of platelets

9

Abciximab: MOA, use

  • monoclonal Ab binds to GP IIb/IIIa ==> prevention of platelet aggregation
  • use
    • acute coronary syndrome
    • angioplasty
    • percutaneous coronary stent placement

10

Clopidogrel (Plavix): MOA

  • anti-platelet drug
  • irreversibly blocks ADP receptor on platelets ==> decreased aggregation adn expression of GP IIb/IIIa

11

Triclopidine: MOA

  • anti-platelet drug
  • irreversibly blocks the ADP receptor on platelets ==> decreased aggregation and the expression of GP IIb/IIIa

12

TPA: MOA

  • tissue plasminogen activator: enzyme that cleaves plasminogen to plasmin ==> breakdown of fibrin clots

13

Physiology of CO poisoning

  • CO binds to oxygen-binding sites on hemoglobin w/250x affinity of oxygen
  • ==> decrease in oxygen-carrying capacity ==> left-shift of the oxy-hemoglobin curve

14

G6PD deficiency ==> 

  • lower levels of the reduced form of NADPH
  • G6PD = enzyme @ hexose monophosphate (HMP) shunt pathway
    • NADP+ ==> NADPH
    • NADPH ==> reduces glutathione w/help of glutathione reductase
    • reduced glutathione protects against oxidant injury
  • oxidative stress ==> hemolytic anemia

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