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Flashcards in Rx_1.1 Deck (23)
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1

How to calculate drug clearance

clearance = rate of drug elimination/plasma drug concentration

2

Common pulmonary infection in HIV patient

  • Pneumocystis jiroveci ==> interstitial pneumonia

3

Fxn + name of HIV surface proteins

  • two imporant envelope proteins:
    • gp41
    • gp120
  • fxn of surface proteins is to bind CD4 receptors ==> envelope fusion and HIV entru into cell

4

Stage of cell cycle of oocyte from birth to ovulation

prophase I

5

Oocyte cell cycle from ovulation ==> embryo

  • at birth: all oocytes arrested in meiosis I (prophase I)
  • after ovulation: oocye progresses through miosis I ==> metaphase II
  • oocyte is arrested in metaphase II until fertilization
  • after fertilization: oocyte completes meiosis II and begins mitotic growth of embryo

6

Lead impact on heme synthesis

  • Lead inhibitions ALA dehydratase and ferrochelatase
    • ALA dehydratase mediates conversion of ALA to porphobilinogen
    • ferrochelatase incorporates iron into protoporphyrin IX (final step in heme synthesis)

7

Tx w/penicillins, sulfonamides followed by fatigue, temp + erythematous macules/papules + burning sensation ==> Dx?

  • Stevens-Johnson syndrome (acute epidermal disorder)
  • urticaria-erythema multiforme-toxic epidermal necrolysis

8

Drugs that ==> Stevens-Johnson syndrome

  • penicillins
  • sulfonamides
  • ethosuximide (anticonvulsant: absence/epileptic seizures)
  • lamotrigine (anti-epileptic; mood stabilizer)

9

Dx?

  • interstitial pneumonia
  • most likely p. jiroveci

10

Tx of Pneumocystitis jiroveci pneumonia (+ MOA)

  • trimethoprim-sulfamethoxazole
    • MOA = inhibitis bacterial folate synthesis via inhibition:
    • dihydropteroate synthetase (trimetho) and dihydrofolate reductase (sulfa)

11

Characteristics of H. pylori

  • gram - 
  • flagellated
  • oxidase +
  • helical organism
  • produces urease
  • most common cause of gastric ulcers
    • classic = antral ulcer with regular, rounded edges and smooth base

12

p53 gene fxn

  • p53 = tumor suppressor gene
  • activated by DNA damage due to chemical insult, oxidate stress, UV radiation ==>
    • arrest of cell cycle progression
    • DNA repair
    • apoptosis

13

location of p53 gene

chromosome 17

14

 Consequences of loss of p53 gene

  • neoplasm:
    • lung
    • breast
    • colon
  • Li-Fraumeni syndrome

15

diagnostic criteria for Li-Fraumeni syndrome

  1. age < 45 yrs
  2. first-degree relative w/cancer @ <45 yrs
  3. another first or second-degree relative w/cancer @ <45 yrs or sarcoma at any age

16

Celiac artery supplies blood to ....? 

  • celiac ==> L gastric, splenic, common

  • foregut structures
    • stomach
    • proximal duodenum
    • liver 
    • gallbladder
    • pancreas
  • spleen

17

fever + runny nose + bilateral cervical lymph nodes ==> Dx?

Corynebacterium diptheria infection

18

MOA of diptheria toxin

  • adenosine diphosphate ribosylation of elongation factor 2 ==>
  • inhibtion of protein syntehsis in animal cells ==> cell death

19

Consequence of 21-alpha-hydroxylase deficiency

unable to synthesize mineralocorticoids ==> chronically elevated renin levels

20

Pathophysiology of osteogenesis imperfect

  • defect in type 1 collagen
  • type 1 collagen production is decreased due to inability of pro-alpha chain mRNA to be translated into polypeptides

21

Mutations in Type 1 osteogenesis imperfecta

  • COL1A1 or COL1A2 (encorde alpha1 and alpha2 collagen chains)
  • ==> inability of mRNA to be translated

 

22

Pathologic finding?

  • Heinz bodies = hemoglobin inclusions w/in red blood cell
  • common in hemolytic anemia

23

Presentation of G6PD

  • previously health patient
    • common in people of African or Mediterranean origin
  • development of hemolytic anemia after treatment for bacterial infection

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