USMLE Rx: Week of 11/21/16 Flashcards
On what receptor does ADH act to cause water retention?
V2 (Think… “2 = tubule”)
True or false: carcinoid syndrome results from a primary carcinoid tumor.
False. Carcinoid syndrome results from metastasis to the liver.
Clay stools result from _____________.
obstruction of the gallbladder
Delayed detachment of the umbilical cord is synonymous with ___________.
LAD (think, “the umbilical cord ADHEREs too long”)
LAD results from a defect in CD______.
18
“You’re no longer a LAD when you turn 18.”
Phosphorylation of mannose residues takes place in which organelle?
The cis-Golgi (the Golgi is the organelle that directs cellular traffic, so it makes sense that mannose phosphorylation would take place here because it directs proteins to lysosomes)
Those with AIDS have the most trouble annihilating ___________.
intracellular pathogens (like Listeria or TB)
Which layer of colonic tissue, when attenuated, causes diverticulosis?
Muscularis propria
What drug should be empirically given to a young adult with suspected meningitis?
Ceftriaxone
Aminoglycosides and tetracyclines both work on the 30S subunit. Which one inhibits tRNA binding?
Tetracycline (T for T!)
Alcohol metabolism leads to a ___________ NADH:NAD+ ratio.
increased; this is important because NAD+ must be present for glycolysis to continue, so pyruvate gets converted to lactate and thus hypoglycemia can occur because of deficient pyruvate
HNPCC increases what other non-GI cancer?
Endometrial, ovarian, and urinary tract
Histologically, how can you differentiate hereditary hemochromatosis and hemosiderosis?
Hemosiderosis will present with iron in macrophages, while hemochromatosis will present with iron in hepatocytes.
What kind of protein is involved in the disorder that presents with cafe-au-lait spots?
An inhibitor of ras (NF-1 on chromosome 17)
What might blistering on and in the mouth suggest in a patient taking an anticonvulsant?
SJS (can present in those taking phenytoin, carbamazepine, ethosuximide, and lamotrigine)
An elderly patient presents with a magnetic-foot gait, incontinence, and recent problems with memory. You check for papilledema and find none. What is likely happening?
Normal-pressure hydrocephalus, which only presents with elevated ICP intermittently (“wet, wobbly, and wacky”).
One important distinction from Alzheimer’s is that those with Alzheimer’s typically develop a lack of coordination late in their disease progression, so if someone is only mildly mentally impaired but has gait disturbance then suspect NPH.
What drug should you give to someone with new-onset diarrhea, tricuspid regurgitation, and periodic flushing?
Octreotide (being carcinoid syndrome)
What histologic appearance do carcinoid tumors have?
Rosettes
What drugs should be given to someone with multiple myeloma metastasized to the bone?
Bisphosphonates (alendronate and risedronate)
What side effect might you worry about in a person taking alendronate who got a tooth extracted?
Osteonecrosis of the jaw
Mitochondrial disorders typically present with what tissues most affected?
Nerves and muscles, because both need lots of energy; think of mitochondrial disorders when someone presents with muscle weakness and nerve dysfunction (such as vision problems)
If you’re given a diagram showing desmosomes and adherens junctions, how can you distinguish the two?
Desmosomes have cytoskeletal filaments that radiate outward, while adherens junctions have straight cytoskeletal filaments.
What are the two steps of galactose metabolism? Which is more commonly affected in galactosemia?
Galactose -> galactose 1-phosphate
Galactose 1-phosphate -> to UDP-galactose -> glucose 1-phosphate
The second step is most commonly impaired in babies with galactosemia.
How can you remember which type of GPCR goes with which receptor?
“After QISSeS, you get a QIQ out of SIQ SQS.”
It goes alphabetically:
- Adrenergic:
- a1 = Gq
- a2 = Gi
- b1 = Gs
- b2 = Gs
- b3 = Gs
- Muscarinic:
- m1 = Gq
- m2 = Gi
- m3 = Gq
- Dopamine:
- d1 = Gs
- d2 = Gi
- Histamine:
- h1 = Gq
- h2 = Gs
- Vasopressin:
- v1 = Gq
- v2 = Gs
What kind of dementia is likely in a patient with visual hallucinations?
Dementia with Lewy bodies
Those with Crohn’s are often given an antibody that attacks soluble __________.
TNFa (being infliximab; think “in-floats-imab”)
What antibiotic inhibits translocation through the ribosome?
Macrolides (“It’s like a MAC truck parked on the tracks… the train can’t go.”)
Informed consent is not needed in emergencies. What is the exception to this rule?
If the patient has previously told you that they don’t want care in that emergency, then the correct course of action is to comply with the patient’s wishes and not administer care.
The esophageal veins arise from the ____________.
left gastric vein
There are five drugs that act on microtubules: vinca alkaloids, colchicine, paclitaxel, ________, and __________.
griseofulvin (antifungal); mebendazole (antihelminthic)
Aldosterone increases the excretion of two things: _____________.
protons and potassium
Left shoulder pain and LUQ abdominal pain are indicative of _______________.
thrombosis to the splenic artery
What cell type do Warthin’s tumors arise from?
Lymphoid cells
Occlusion of the ____________ artery can lead to “locked-in” syndrome, a state in which people are fully conscious but only able to blink.
basilar
What are some characteristics of pathologic grief?
Delayed grief: not feeling anything at the time but then grieving months or years later
Inhibited grief: denying feeling anything
Excessive or prolonged grief
What amino acids are essential?
All of the ketogenic and ketogenic/glucogenic; valine, methionine, and histidine
____________ are conditionally essential amino acids.
Arginine and cysteine
What are the four Ds of physician malpractice?
Dereliction of Duty causing Direct Damage to the patient
Describe the presentation of myotonic dystrophy.
It is a nucleotide repeat disorder that presents with proximal muscle weakness, delayed relaxation of muscles, cataracts, and glucose intolerance.
CCTG repeat: cataracts, chair-bound, tense, glucose
Differentiate the mechanisms of vancomycin and the beta-lactams.
Vancomycin inhibits peptidoglycan polymerization (you can’t make the caraVAN), while the beta-lactams prevent cross-linking (“BET you can’t CROSS your LACes”)
One common side effect of ondansetron is ______________.
headaches
If a patient has yet to pass stool, what is a good way to distinguish volvulus and diverticular hemorrhage?
Volvulus is unlikely to lead to fever or leukocytosis, whereas diverticular hemorrhage can.
What is First Aid’s mnemonic for the spinal reflexes?
S1, S2: buckle my shoe (Achilles)
L3, L4: kick the door (patellar)
C5, C6: pick up sticks (biceps)
C7, C8: lay them straight (triceps reflex)
L1, L2: testicles move (cremasteric reflex)
S3, S4: winks galore (anal wink reflex)
True or false: give physostigmine to someone who’s had an organophosphate overdose.
False. Give atropine and pralidoxime –more ACh will make organophosphate poisoning worse.
Normally, dopamine inhibits the ________________.
putamen, which normally inhibits the Gpe;
The Gpe normally inhibits the ______________.
subthalamic nucleus; without dopamine, the putamen is not inhibited and thus it over inhibits the Gpe; because the Gpe is supposed to inhibit the subthalamic nucleus, it fails to do so and thus the subthalamic nucleus inhibits the Gpi
What are GI slow waves?
Rhythmic depolarizations and repolarizations of the GI tract that occur about every 20 seconds
If a tRNA has a mutation that damages its hydrolytic site, what will occur?
Different amino acids will bind to that tRNA and then get incorporated where the original amino acid should have been.
What is the mechanism of the antiviral that causes agranulocytosis?
Ganciclovir mimics dGTP and then inhibits viral DNA polymerase. (Think of the Gs: Ganciclovir = dGtp.)
If a patient with AIDS has visual distortions, what infection should you be worried about?
CMV retinitis
_____________ modulates the levels of IL-2 and is thus a great immunosuppressant.
Tacrolimus
You know that macrolides bind to the 50S subunit, but what does it prevent?
Translocation of the tRNA subunits
Think of a CROw standing on a still LOCOmotive.
What part of the lymph node houses T cells?
The paracortex
