Set 27 Flashcards
What effect does stress have on adipocytes?
Stress —> sympathetic activation —> NE and Epi from adrenal medulla —> activation of triglyceride lipase in fat cells —> rapid breakdown of TGs and mobilization of fatty acids to be used as energy
Stress -> release of corticotropin from anterior pituitary —> secretion of glucocorticoids from adrenal cortex —> activation of triglyceride lipase in fat cells —> rapid breakdown of TGs and mobilization of fatty acids to be used as energy
A 67-year-old man is being treated with leuprolide for advanced prostate cancer. What is the mechanism of action of leuprolide?
Synthetic GnRH analog with agonist properties when used in a pulsatile fashion; antagonist when used in continuous fashion (down regulates GnRH receptor in anterior pituitary —> decreased FSH/LH)
Used in fertility (pulsatile), postate cancer (continuous w/ flutamide), uterine fibroids (continuous), precocious puberty (continuous)
Want to suppress testosterone in prostate cancer (decreased LH and FSH leads to decreased testosterone production)
A chronic alcoholic with cirrhosis begins to experience a tremor and blurred vision. You suspect that these symptoms might be due to hyperammonemia due to his progressive liver disease. What is another hereditary cause of hyperammonemia? What are some other findings associated with hyperammonemia?
Urea cycle enzyme deficiencies - Ornithine transcarbamylase deficiency: X-linked recessive disorder. Present with elevated ammonia levels the first few days of life, decreased BUN, symptoms of hyperammonemia and the presence of orotic acid in blood and urine (excess carbamoyl phosphate is converted to orotic acid which is part of the pyrimidine synthesis pathway)
Results in excess NH4+ which depletes alpha-ketoglutarate, leading to inhibition of TCA cycle
Ammonia intoxication - tremor (asterixis), slurring of speech, somnolence, vomiting, cerebral edema, blurring of vision
What features distinguish a thyroglossal duct cyst from a branchial cleft cyst? What is the remnant of the thyroglossal duct? Explain the development of the thyroid gland.
Thyroglossal duct cyst presents as an anterior midline neck mass that moves with swallowing or protrusion of the tongue (vs. persistent cervical sinus leading to branchial cleft cysts in lateral neck, does not move with swallowing)
Foramen cecum is normal remnant of thyroglossal duct
Thyroid diverticulum arises from the floor of the primitive pharynx, and descends into neck. Connected to tongue by thyroglossal duct, which normally disappears but may persist as pyramidal lobe of thyroid
A 46-year-old schizophrenic woman has been treated with an atypical antipsychotic with good results for several years. Routine labs reveal a precipitous drop in her WBCs. Which drug is this patient likely taking, and how frequently must her labs be drawn to watch for this problem?
Clonzapine
May cause agranulocytosis (requires weekly WBC monitoring)
Does a partial agonist always have a lower maximal efficacy than a full agonist? Does a partial agonist always have a lower potency than a full agonist?
A partial agonist acts at the same site as a full agonist but with lower maximal effect (decreased efficacy). Potency is an independent variable (depends on how much of a drug you need to get the effect)
How is cystic fibrosis diagnosed?
Increased chloride concentration in sweat (>60 mEq/l) aka chloride sweat tests (induce sweating w/ pilocarpine)
Genetic testing (90% of cases)
Chloride secretion in the nasal epithelium
What are the common causes of metabolic acidosis with an elevated anion gap?
MUDPILES Methanol (formic acid) Uremia Diabetic ketoacidosis Propylene glycol Iron tablets or Isoniazide (INH) Lactic acidosis Ethylene glycol (oxalic acid) Salicylates (late)
You are conducting a study to determine the reduction in risk of developing a relapsing depressive episode with antidepressant X when compared to a placebo treatment. What is this determination called? What is attributable risk, and how is it calculated?
Absolute risk reduction: the difference in risk (not proportion) attributable to the intervention as compared to a control
Attributable risk is the difference in risk between exposed and unexposed groups or the proportion of disease occurrences that are attributable to the exposure (e.g., if risk of lung cancer in smokers is 21% and risk in nonsmokers is 1% then 20% (0.20) of the 21% risk of lung cancer in smokers is attributable to smoking).
Equation: # smokers with lung cancer/all smokers - # nonsmokers with lung cancer/all nonsmokers
Given the following clinical situations, classify each as type I, II, III, or IV hypersensitivity.
Asthma exacerbation
Type I
Given the following clinical situations, classify each as type I, II, III, or IV hypersensitivity.
Poison ivy dermatitis
Type IV
Given the following clinical situations, classify each as type I, II, III, or IV hypersensitivity.
Goodpasture syndrome
Type II
Given the following clinical situations, classify each as type I, II, III, or IV hypersensitivity.
Arthus reaction
Type III
Given the following clinical situations, classify each as type I, II, III, or IV hypersensitivity.
Anaphylaxis
Type I
Given the following clinical situations, classify each as type I, II, III, or IV hypersensitivity.
Serum sickness
Type III
