review block 3

  1. someone who is taking only IV glucose will have problems synthesizing what?
    • things derived from arachidonic acid
    • cycloxygenase -> prostagladins (anti-inflammation, cAMP stimulation), thromboxane synthase -> thromboxane A2 (vasoconstriction, platelet aggregation)
    • lipoxygenase -> leukotrienes (chemotaxis, constriction of sm. muscle/bronchioles)
  2. What can raise HDL?
    • niacin
    • exercise (12 mi/wk)
    • mutations in CETP, cholesterol esterase transfer protein
  3. What is the composition of surfactant in the lungs that preterm infants lack?
    • phosphatidylcholines: DPPC (dipalmitoylphosphatidylcholine)
    • secreted by type II pneumocytes
  4. ketogenic v. glucogenic aa's
    • aa's whose metabolism leads to pyruvate or TCA cycle intermediates = glucogenic
    • acetylCoA/acetoacetylCoA = ketogenic
  5. Maple syrup urine disease
    • deficiency in branched-chain alpha-keto acid dehydrogenase
    • decarboxylates leucine, isoleucine, and valine
    • fatal in first weeks of life
    • buildup of ile, val, leu causes neurological problems
  6. cofactor needed to transaminate aa's
    B6 or pyridoxine
  7. What inhibits and what activates pyrimidine synthesis?
    • Inhibit: UTP
    • Activate: ATP, PRPP
  8. Causes of gout
    • undergoing chemotherapy of a bulky tumor
    • Deficiency in hypoxanthine-guanine phosphoribosyltransferase (Lesch-Nyhan)
    • elevated levels of 5-phosphoribosyl-1-pyrophosphate (PRPP)
    • underexcreting uric acid
  9. How would cancer cells become resistant to methotrexate?
    Overproduction of dihydrofolate reductase
  10. What decreases triglyceride levels?
    • Decreases:
    • Insulin
    • Gemfibrozil (fibrates) - specifically decreases VLDL
    • Fasting
    • HMG-CoA-reductase inhibitors (statins)
    • Increases:
    • Estrogen
  11. If you pierced the skin lateral to the rectus abdominis, you'd pass through:
    skin, superficial fascia, external abdominal oblique, internal abdominal oblique, transversus abdominis, transversalis fascia, extraperitoneal fat, parietal peritoneum
  12. Anemia + iron deficiency due to chronic infections. What are hepcidin and ferroportin levels?
    • increased plasma level of hepcidin
    • decreased ferroportin activity in macrophages
    • decreased ferroportin activity in duodenal enterocytes
  13. protein energy malnutrition
    • Kwashiorkor - inadequate intake of protein -> edema (due to hypoalbuminemia)
    • Marasmus - inadequate calories -> no edema
  14. Phenylketonuria (PKU)
    • defective phenylalanine hydroxylase (PAH)
    • uses tetrahydrobiopterin (BH4) cofactor
    • mental retardation (but not at birth) - must begin diet 7-10d after birth
    • hyperphenylalanemia may inhibit transport of other aa's into brain, decreased synth of neurotransmitters
    • treatment: diet low in F - still an essential aa
    • if expectant PKU mom has d/c diet, she must resume it for the health of the unborn child
  15. alkaptonuria
    • homogentisate oxidase defect, autosomal recessive
    • arthritis, darkening of urine upon standing in infants
    • relatively harmless, eventual darkening of sclera and cartilage
  16. maple syrup urine disease
    • branched-chain ketoacid DH
    • autosomal recessive
    • non-specific symptoms within the first weeks of life
    • CNS toxicity later in life
    • treatment: diets low in leucine, isoleucine, valine. Dialysis if acidosis is too severe
  17. causes of hypercalcemia
    hyperparathyroidism, hemochromatosis, hypothyroidism
  18. trabecular v. cortical bone
    • trabecular: axial, more active metabolically, first site of osteoporosis
    • cortical: peripheral bone
  19. osteoporosis
    • resorption exceeds bone formation
    • ratio of mineral to matrix remains normal
Card Set
review block 3
block 3