Day 1 Flashcards
Which immune response is responsible for hyperacute, acute, and chronic transplant rejection? What is the time frame for each? (FA15 p217) (FA16 p211) (SU p384-385)
Hyperacute - (within minutes) pre-existing recipient antibodies to donor antigen (type II hypersensitivity reaction), activate complement
clx - widespread thrombosis of graft vessels –> ischemia and necrosis
tx - graft must be removed
Acute - (Weeks to months) Cellular: CD8+ T cells activated against donor MHCs (type IV hypersensitivity reaction)
Humoral: similar to hyperacute, except antibodies develop after transplant
clx - vasculitis of graft with dense interstitial lymphocytic infiltrate
tx - prevent/reverse with immunosuppressants
Chronic - (months to years) CD4+ T cells respond to recipient APCs presenting donor peptides, including allogeneic MHC
Both cellular and humoral components (type II and IV hypersensitivity reactions)
clx - Recipient T cells react and secrete cytokines –> proliferation of vascular smooth muscle, parenchymal atrophy, interstitial fibrosis
Bronchiolitis obliterans, Accelerated atherosclerosis, Chronc graft nephropathy, Vanishing bile duct syndrome
What is the treatment for digoxin toxicity? (FA15 p257) (FA16 p251) (SU p68) (GG p803)
Tx for Digoxin toxicity = Anti-dig Fab fragments
Normalize K and Mg
Brady –> atropine
Other arrhythmias –> ACLS
For which infections is vancomycin a good choice? How does vancomycin resistance develop? (FA15
p183) (FA16 p173) (SU p338)
Vancomycin = GRAM + bugs only serious, multi-drug resistant organisms MRSA S. epidermidis sensitive Enterococcus species Clostridium Difficile (oral dose for pseudomembranous colitis)
Resistance to Vanc? –> modification of amino acid sequence D-ala D-ala to D-ala D-lac
“Pay back 2 D-alas (dollars) for VANdalizing”
Do atypical antipsychotics primarily address the negative or positive symptoms of schizophrenia? How
does the mechanism of action of typical antipsychotics differ from the mechanism of action of the
atypical antipsychotics? (FA15 p509, 521) (FA16 p514, 525) (SU p53)
Positive symptoms = delusions, hallucinations, disorganized speech, Disorganized catatonic behavior
Negative symptoms = flat affect, avolition, anhedonia, asociality, alogia)
Typical = block dopamine D2 receptors (increase cAMP) Atypical = not completely understood, different mechanisms
A 67-year-old man with new-onset hepatic failure and normal renal function is currently taking a drug
metabolized and excreted by the kidneys. Would you need to change the loading dose or maintenance
dose of this medication because of this hepatic failure? If this patient were to develop hepatorenal
failure, would you need to change the loading dose or maintenance dose of the medicine? (FA15
p243) (FA16 p237) (SU p395)
In renal or liver disease:
Maintenance dose = decreased
Loading dose = same
What substances compose the matrix of the bone? (Phys p957)
Organic matrix (30%)
collagen, chondroitin sulfate, hyaluronic acid
Crystalline salts (70%)
calcium, phosphate, hydroxyapatite
While thiazide and loop diuretics are known for wasting potassium in the urine, there are other
diuretics that conserve it. Which diuretics are these? What are their mechanisms of action? What are
their important side effects? (FA15 p554) (FA16 p558) (SU p165)
Potassium-sparing diuretics: Spironolactone (aldosterone antagonists) Eplerenone (aldosterone antagonists) Triamterene (block Na channels) Amiloride (block Na channels) Distal tubules
Side Effects!
Hyperkalemia –> arrhythmia
SPIRONOLACTONE –> endocrine effects (gynecomastia, antiandrogen effect)
A 66-year-old woman is being treated in the ER for an acute MI. Nitroglycerin is given with the
expectation that it will vasodilate which vessels preferentially? Another patient in the ICU is on
hydralazine for acute treatment of his severe hypertension. How does hydralazine function? (FA15
p304-305) (FA16 p298-299) (SU p77)
Nitroglycerin = vasodilates vascular smooth muscles VEINS»>ARTERIES Decreases preload
Hydralazine = vasodilates arterioles»_space; veins Decreases afterload
What risk factors are associated with cholesterol gallstones? What risk factors are associated with
pigment gallstones? (FA15 p375) (FA16 p372) (SU p135)
Fat, Forty, Female, Fertile
Cholesterol stones = obesity, Crohn’s, advanced age, estrogen therapy, multiparity, rapid wt loss, Native American
Pigmented stones = Crohn’s, hemolysis, alcoholic cirrhosis, advanced age, biliary infection, TPN
A 35-year-old woman with multiple sclerosis presents to clinic with internuclear ophthalmoplegia.
What is internuclear ophthalmoplegia? (FA15 p486) (FA16 p490) (SU p35)
Medial Longitudinal Fasciculus (MLF): pair of tracts that allows for crosstalk between CN VI and CN III nuclei. Coordinates both eyes to move in same horizontal direction. Highly myelinated (must communicate quickly so eyes move at same time). Lesions may be unilateral or bilateral (latter classically seen in multiple sclerosis).
Lesion in MLF = INTERNUCLEAR OPHTHALMOPLEGIA (INO), a conjugate horizontal gaze palsy.
A female infant is brought to the clinic for evaluation of her genitalia. On exam, clitoromegaly and labial fusion is noted. Lab studies reveal elevated 17-hydroxyprogesterone levels. What is the most common form of adrenal hyperplasia? Which hormone levels are altered as a result of this enzyme deficiency? What are the clinical manifestations of this enzyme deficiency? (FA15 p318) (FA16 p312) (SU p168, 186)
MC form of Adrenal Hyperplasia = 21-hydroxylase deficiency
Decreased: aldosterone cortisol Increased: sex hormones
Increased renin / increased 17-hydroxyprogesterone
Clx - Hypotension Volume depletion Hyperkalemia (due to decreased aldosterone) Masculinization in females
Infancy = Salt Wasting Childhood = Precocious Puberty
What is the mechanism of action of the following antiemetics? (FA15 p251, 380) (FA16 p245, 376) (SU p139-141) (GG p1341-1344) Scopolamine Promethazine Prochlorperazine Metoclopramide Ondansetron
Muscarinic antagonist
CNS
motion sicknesss / decreases oral secretions
M1 antagonist
------------------------------- Histamine antagonist D2 dopamine antagonist --------------------------------- D2 dopamine antagonist ---------------------------------- D2 receptor antagonist / increases resting tone, contractility, LES tone, motility Does not influence colon transport time
5-HT3 antagonist, decrease vagal stimulation POWERFUL central-acting antiemetic
clx: post-op and chemo/cancer therapy pts
Side effects = headache, constipation, QT interval prolongation
A 25-year-old man complains of a scrotal mass and pain made worse by coughing or sneezing. A
scrotal exam reveals a palpable scrotal protrusion with the Valsalva maneuver. What type of hernia is
this patient experiencing? What type of hernia protrudes through Hesselbach’s triangle? What
structures form Hesselbach’s triangle? (FA15 p352) (FA16 p349) (SU p250-251)
Scrotal Mass = Indirect inguinal hernia
Hesselbach’s triangle = Direct inguinal hernia
Hesselbacj’s trinangle: Femoral Vessels / Inguinal ligament / Rectus abdominis muscle
How does a decrease in renal artery pressure cause an increase in blood pressure? (FA15 p534) (FA16
p540) (SU p147)
Decrease in renal artery pressure causes secretion of RENIN by JG cells. ANGIOTENSINOGEN is released from the liver and converted to ANGIOTENSIN I by RENIN. ANGIOTENSIN I is then converted to ANGIOTENSIN II by ACE from the lungs and kidney.
Angiotensin II acts on receptors type AT1 on vascular smooth muscle
Constricts efferent arterioles of glomerulus, this increases FF to preserve GFR in low volume state
Aldosterone secreted to increase Na channel and Na/K pump in principal cells / enhances K and H excretion by way of principal cell K channels and alpha-intercalated cell H ATPase / creates favorable Na gradient for Na and H2O reabsorption
ADH from posterior pituitary, increase aquaporin insertion in principal cells / H2O reabsorption
increase PCT Na/H activity / Na, HCO3, H2O reabsorption (can permit contraction alkalosis
Stimulates hypothalamus / stimulates THIRST
What are the three endogenous androgens in order from the most potent to the least potent? (FA15
p577) (FA16 p582) (SU p169)
Endogenous Androgens MOST POTENT DHT Testosterone Androstenedione
What is Osler-Weber-Rendu syndrome? (FA15 p83) (FA16 p71) (SU p90) (R p730) (H p409)
Hereditary Hemorrhagic Telangiectesia
inherited disorder of blood vessels / branching skin lesions (telegiectesia), recurrent epistaxis, skin discoloration, arteriovenous malformations (AVMs), GI bleeding, hematuria.
What is the fibrous band attached to the testis and scrotum that aids in normal testicular descent?
What is this structure called in females? (FA15 p569) (FA16 p573) (SU p198-200)
Gubernaculum (band of fibrous tissue) anchors testes within scrotum –> ovarian ligament +round ligament
What are the effects of NSAIDs’ inhibition of PGE2? (FA15 p445) (FA16 p447) (SU p243) What role do
prostaglandins and angiotensin II play on the renal arterioles? (FA15 p530, 532) (FA16 p535, 537) (SU
p148)
NSAIDs – reversibly inhibits cyclooxygenase (both COX-1 and COX-2) blocks prostaglandin synthesis
clx – antipyretic / analgesic / anti-inflamm / Indomethacin used to close PDA
Side effects – interstitial nephritis, gastric ulcer (prostaglandins protect gastric mucosa), renal ischemia (prostaglandins vasodilate afferent arteriole)
Prostaglandins preferentially dilate afferent arteriole (increase RPF, increases GFR, so no change in FF)
ATII - stimulates Na/H exchange –> increase Na, H2O, and HCO3 reabsorption (permitting contraction alkalosis)
What is the difference between a case-control study, a cohort study, and a clinical trial? (FA15 p48)
(FA16 p32) (SU p17-18) Which studies use odds ratios, and which use relative risks? (FA15 p48, 50)
(FA16 p32, 34) (SU p18)
Case-control study - look for prior exposure or risk factor “what happened” (OR)
Cohort study - Prospective (RR)
Clinical trial - experimental study involving humans.
T cells are found in the paracortex of the lymph node between the follicles and the medulla. Which
cytokines are secreted by the two different types of helper T cells (Th1 and Th2)? (FA15 p202) (FA16
p194) (SU p373-374)
Th1 - IL-2 / IFN-gamma
Th2 - IL-4 / IL-5 / IL-10 / IL-13
A 32-year-old man is being treated for alcohol dependence with disulfiram. One night, he begins drinking and later has severe nausea and vomiting. What is the mechanism of action of disulfiram? What other drugs have a disulfiram-like effect? (FA15 p95) (FA16 p83) (SU p305) (GG p643-644)
Mechanism of action of Disulfiram - inhibits acetaldehyde dehydrogenase (acetaldehyde accumulates, contributing to hangover symptoms)
Fomepizole - inhibits alcohol dehydrogenase, antidote for methanol and ethylene glycol poisoning
Metronidazole
Certain Cephalosporins
Griseofulvin
1st gen Sulfonylureas
What is PPAR-γ? How is it relevant to the treatment of diabetes mellitus? (FA15 p338-339) (FA16 p334-335) (SU p181)
PPAR-gamma - genes activated by PPAR regulate fatty acid storage and glucose metabolism. activation of PPAR increase insulin sensitivity and levels of adiponectin.
Peroxisome proliferator-activated receptor gamma
nuclear receptor and transcription factor found in adipose tissue
plays a role in adipocyte differentiation
TZD binds PPAR-gamma and improve insulin sensitivity
The thalamus is a relay station that conducts signals to and from the brain. Which thalamic nuclei are the relay stations for each of the following body sensations/activities? (FA15 p456) (FA16 p458) (SU p40) • Auditory sensation • Visual sensation • Motor to the body • Facial sensation • Body sensation
Medial geniculate nucleus ------------------------- Lateral geniculate nucleus ------------------------- Ventral lateral nucleus ------------------------- Ventral postero-medial nucleus ------------------------- Ventral postero-lateral nucleus
A 40-year-old man arrives at your clinic for his first physical in 20 years. He reeks of cigarette smoke,
and you notice his jacket bears the logo of his favorite tobacco company. He proudly informs you that
he got this great jacket by redeeming his cigarette cartons. At what stage of change in overcoming his
smoking habit is this man? (FA15 p517) (FA16 p521)
Precontemplation - not yet acknowledging that there is a problem
Contemplation Preparation Action Maintenance Relapse
A 23-year-old man comes to your clinic with a fever of 39°C, a headache, and myalgias. This is the
second fever he has had in the last two weeks. He recently finished treatment to eradicate the lice
infestation that he acquired during a recent trip to Mexico. What organism might be responsible for
this man’s recurrent fever? (FA15 p142) (FA16 p132)
(X) Rickettsia prowazekii (Epidemic typhus : recurrent fever from human louse)
Borrelia Recurrentis = relapsing fever due to variable surface antigens (louse/lice) Sudden fever Muscle or joint aches Nausea Rash
What physiologically is taking place in decompression sickness? (Phys p538)
Decompression sickness
gases (especially nitrogen) that had dissolved in the blood at high pressures form bubbles that can occlude blood vessels
Which drugs are known to cause aplastic anemia? What is the treatment for aplastic anemia? (FA15
p258, 393) (FA16 p252, 391) (SU p396, 263-264)
Carbamazepine, Methimazole, NSAIDs, Benzene, Chloramphenicol, Propylthiouracil / anti-Cancer drugs
immunosuppressive agents (antithymocyte globulin, cyclosporine), bone marrow allograft, RBC/platelet transfusion, bone marrow stimulation GM-CSF
Is a 34-year-old schizophrenic patient having active hallucinations, who is not oriented to time, place,
or person, able to legally agree to a plan of care? What factors must be in place in order for a patient
to have the capacity to make a decision? (FA15 p57) (FA16 p40) (SU p21)
No
Needs to make and communicate a clear choice
Needs to be informed and understand risks, benefits, and alternatives
Decision must be stable over time
Decision is consistent with patient’s values and goals
Decision is not based on hallucinations or delusions
