Q Banks: Week of 03/13/17 Flashcards
In general, when should you use a broad-spectrum antiepileptic and when should you use a narrow-spectrum antiepileptic?
Narrow-spectrum anticonvulsants (carbamazepine, phenytoin) should be used in focal seizures. Focal seizures predominately involve one hemisphere of the brain (like the waitress in the Sketchy scene shaking just her right arm). Broad-spectrum antiepileptics are given in generalized seizures –those that involve both hemispheres from the onset (like the Incans shaking both elbows).
What happens to the hemoglobin in methemoglobinemia?
It is oxidized and cannot bind oxygen (mimicking anemia).
Which nerve is in the lateral compartment of the lower leg?
The superficial peroneal nerve (the deep peroneal nerve is in the anterior compartment and the tibial nerve is in the deep posterior compartment)
Explain the role of P bodies.
P bodies are proteins in the cytosol of eukaryotic cells that regulate mRNA. They can degrade mRNA or store mRNA for later use.
Part of true patient confidentiality means that physicians are not able to tell people even ________________.
whether someone is or isn’t their patient
True or false: benzodiazepines bind to the same site as GABA while barbiturates bind to an allosteric site.
False. Both bind to an allosteric site.
The main risk factor for aortic dissection is _________________.
hypertension
Differentiate postpartum blues and postpartum depression.
Postpartum blues is an extremely common condition (80% of women after giving birth) that involves tearfulness and depression in the first week after delivery. If this doesn’t go away within two weeks, postpartum depression may be considered.
Any consideration of suicidality indicates postpartum depression.
What is the main difference between uterine didelphys and failure of septal dissolution?
Persistent septums will present with a normal outer shape of the uterus, whereas uterine didelphys will have an abnormal outer shape.
Other than macrophages, what cell type proliferates in atheromatous plaques?
Smooth muscle cells!
Platelets, endothelial cells, and macrophages release growth factors for smooth muscle cells that enter the plaque area and lead to further swelling.
A patient appears icteric after getting surgery in a third-world country. What might have happened?
Halothane is still used in many poorer countries for surgical anesthesia and can cause hepatotoxicity. This often presents days later with a shrunken liver and elevated transaminases.
Through which foramen do the EOM nerves enter the orbit?
Through the superior orbital fissure (along with the ophthalmic branch of the trigeminal nerve)
Note: recall that the three branches of the trigeminal nerve enter through the Superior orbital fissure, foramen Rotundum, and foramen Ovale (“Standing Room Only”)
Which ECM proteins does integrin bind?
fibronectIN and laminIN (also collagEN)
Why is blood in the left atrium less oxygenated that blood in the pulmonary vessels?
Because the bronchial arteries empty deoxygenated blood into the pulmonary veins
What kind of receptor is thyroid hormone?
Nuclear receptor
Fecal incontinence after labor is often due to _______________.
stretch injuries of the pudendal nerve
Explain the pathogenesis of rickets.
Without vitamin D, calcium levels drop. As such, bone cannot be mineralized and the bones will primarily be osteoid.
Botulinum can be tested for by _______________.
looking in stools for toxin
There are four different etiologies of genital ulcers. Talk about how each can be distinguished.
- HSV: multiple shallow painful ulcers that recur
- H. ducreyi: multiple deep painful ulcers
- C. trochomatis: painless ulcers that go away followed by painful inguinal swelling
- T. pallidum: single painless ulcers
What bicarb values are typical of chronic (compensated) and acute (uncompensated) respiratory acidosis?
- Chronic: bicarb greater than 30
* Acute: bicarb less than 30
What components make up metabolic syndrome?
At least three of the following: •HDL less than 40 (women) or 35 (men) •Elevated triglycerides •Increased waist circumference •Insulin resistance (as detected on fasting glucose) •Hypertension
Notice that LDL or total cholesterol is not on there!
Cytogenetic studies often show _____________ in boys with fragile X syndrome.
a gap near the tip of the X chromosome
Proline and lysine are hydroxylated in the ______________.
endoplasmic reticulum
_______________ in the stool is strongly suggestive o S. stercoralis.
Rhabditidiform larvae
Rhabditidiform larvae are the non-infectious larvae. Strongyloides larvae can convert to the filariform larvae in the intestine, however, and reinfect the host.
What happens to arterial pH during strenuous exercise?
You might think it would go up due to hyperventilation, but the arterial pH generally stays the same. If the strenuous exercise is weight lifting and is extreme, then lactate production can lower the pH.
Both ____________ and ___________ increase cholesterol synthesis.
(Dyslipidemia drugs)
cholestyramine; ezetimibe
Diffuse erythema and epidermis that sloughs off easily is indicative of ______________ (particularly common in young children).
Staphylococcal scalded skin syndrome
Low levels of oxygen lead to decreased activity of pyruvate ______________.
dehydrogenase
Pyruvate dehydrogenase is the last enzyme before the TCA cycle. Low levels of oxygen lead to increased activity of lactate dehydrogenase and decreased conversion of pyruvate to acetyl CoA.
Note: you might confuse this enzyme with pyruvate kinase. Pyruvate kinase converts PEP to pyruvate and will thus NOT be decreased in lactate production, because pyruvate gets converted to lactate.
Those with Graves’ disease often have exophthalmos. Why does this occur?
Stimulation of TSH receptors in the retro-orbital space leads to inflammatory infiltrate. That inflammatory infiltrate – Th cells – leads to stimulation of fibroblasts.
Once again, differentiate erosion and ulcer.
- Erosions are extremely simple: they are damages to stomach/intestinal tissue that only go into the mucosa –the topmost layer.
- Ulcers are any erosion that goes deeper than the mucosa (the next layer down would be muscularis mucosa and the one beyond that is the submucosa).
Thiazide diuretics block the NaCl cotransporter. Why do they lower potassium?
Lowering blood pressure with any diuretic –thiazides included – will stimulate the release of aldosterone which can lower potassium. Chlorthalidone appears to do this more than indapamide or hydrochlorothiazide.
Why do those who’ve had gastrojejunostomies need to take iron?
Because that procedure creates a hole between the stomach and the jejunum – bypassing the duodenum in which Fe is absorbed.
Other than metaplasia, what histologic signs indicate GERD?
- Presence of neutrophils and eosinophils in the mucosa
* Elongation of the lamina propria
When has the neural tube finished closing?
22 days
True or false: complete molar pregnancies have to be either 46, XX or 46, YY.
False. There has never been a 46, YY complete molar pregnancy observed. Furthermore, there can also be 46, XY pregnancies in which two sperm fertilize one egg, although that is much less common than one sperm dividing inside an empty egg (leading to 46, XX).
How might a complete molar pregnancy be described compared to a partial molar pregnancy?
Complete molar pregnancies will be entirely cystic, while partial molar pregnancies will have fetal parts or normal placenta.
In what form does Candida exist in the blood?
As single-celled yeast with pseudohyphae (remember the snowcone in the Sketchy scene!)
Hereditary pulmonary fibrosis is due to what pathology?
Smooth muscle proliferation leading to occlusion of the pulmonary arteries that leads to “capillary tufts”
A patient presents 11 days after starting a new, experimental drug with pruritis and joint pain. What might be going on?
Serum sickness
“New treatments” might indicate monoclonal antibodies that can deposit in tissues as immune complexes. This will present with arthralgia, pruritus, and neutrophil infiltration of small blood vessels with fibrinoid necrosis.
The ophthalmic artery branches off the ______________ artery.
internal carotid
The external carotid ultimately forks into the __________________.
maxillary and superficial temporal arteries
Which kind of galactosemia causes cataracts?
Both!
Deficiency in galactose 1-phosphate uridyl transferase produces the more severe phenotype, usually leading to hepatic and renal damage in infancy. Galactokinase deficiency, however, leads to a less severe phenotype. In both states, however, galactitol accumulates and damages the lens.
Surprisingly, ______________ are not required for a diagnosis of bipolar I disorder.
depressive episodes
______________ is absolutely required for a diagnosis of bipolar I disorder.
Greater than one week of elevated or irritable mood with increased energy
Why are those with PCOS at increased risk of endometrial carcinoma?
One of the components of PCOS is increased estrogen without progesterone. The estrogen results from the increased enzyme activity of androgen-synthesizing enzymes which increases the amount of androgens that can be converted to estrone peripherally.
Normally, the menstrual cycle leads to periods of estrogen withdrawal and progesterone surge. The progesterone surge decreases the risk of endometrial carcinoma. Without this, the risk of endometrial cancer rises.
You’re pretty familiar with the fact that metoprolol and atenolol are B1 selective. List the two other B1-selective beta blockers.
Bisoprolol and nebivolol
Good way to remember this: B1soprolol and neB1volol
Blood cultures and _____________ are the most sensitive tests for osteomyelitis.
MRI
“MrI for osteoMYE!”
Suspect _____________ in a patient with back pain who’s recently had bacteremia or endocarditis.
vertebral osteomyelitis
A patient presents with renal failure. Kidney biopsy reveals bipyramidal crystals (like one pyramid on another). What substance might he have ingested?
Ethylene glycol leads to precipitation of oxalate crystals (described in the stem), which are a downstream metabolite.
This causes acute tubular injury.
The median nerve passes between which two muscles in the forearm?
Flexor digitorum profundis and flexor digitorum superficialis
E. coli is indole-____________.
positive (think of a lazy person on a bean bag in the Sketchy scene –they’re INDOLEnt-positive)
What does it mean to be indole-positive?
Some bacteria can convert tryptophan to indole.
True or false: urine catheters should be changed frequently to avoid infection.
False-ish. While changing a catheter does lead to a temporary reduction in bacterial load, it does not protect against UTI. The best prophylactic measure against catheter-associated UTI is removal of the catheter when no longer necessary.
Describe the typical course of RSV.
Usually, the acute illness (fever, wheezing, increased work of breathing, rhinorrhea) lasts between 3 days and one week, but the cough can persist for up to one month.
Homocystinuria presents with a Marfanoid body habitus and _____________.
lens subluxation
Why does the liver become black in Dubin-Johnson syndrome?
Because the liver is also unable to excrete epinephrine metabolites which are dark (because they are derived from tyrosine)
From which arteries does the ureter draw blood?
- Proximal: renal artery
* Distal: superior vesical artery
A patient presents with a uniformly enlarged uterus and menorrhagia. From her clinical history, how can you distinguish between adenomyosis and endometrial hyperplasia?
Because adenomyosis is deep into the muscle, the bleeding will be painful!
Differentiate actinic keratosis from seborrheic keratosis.
- Seborrheic keratosis has a stuck-on look (think “StucK on”).
- Actinic keratosis is a scaly macule on an erythematous base. They are often “felt more than seen.” They can transition to SCC.
True or false: the characteristic “owl-eye” cells of Hodgkin’s are derived from T cells.
False. They are B-cell derivatives. The fact that they are B cells accounts for how well they can attract macrophages, which account for the bulk of Hodgkin’s lymphadenopathy.
Where do the internal hemorrhoids get autonomic innervation?
The hypogastric plexus
During excision of external hemorrhoids, sensory blockade of ______________ is usually done.
the pudendal nerve
Which vitamin deficiency can lead to congestive heart failure?
Thiamine
Beriberi (thiamine deficiency) can present as either wet –in which patients have congestive heart failure –or dry –in which they don’t. The other key features are symmetric neuropathy and confusion.
True or false: those with Kartagener’s disease often have fat malabsorption due to failure of pancreatic cilia.
False. Kartagener’s presents with the classic triad of dextrocardia, infertility, and persistent pulmonary infection (which also presents as sinusitis).
Amniotic fluid embolism –which can lead to DIC after labor –will present with _______________ on historlogic exam of pulmonary vessels.
fetal squamous cells
Note: the fluid will pass through but the scant cells in the amniotic fluid will be caught.
For a diagnosis of schizophrenia, you must have ____________ for greater than 6 months.
2 or more symptoms, of which one must be delusions, hallucinations, or disorganized speech
Nitrates are recommended to be taken with periodic breaks to reduce which of the following effects? •Effect potentiation •Pharmacodynamic drug antagonism •Tolerance •Withdrawal symptoms
Tolerance
Tolerance rapidly develops to nitrates so drug holidays are recommended.
Effect potentiation refers to one drug’s ability to stimulate the effect of another.
Pharmacodynamic drug antagonism is when one drug causes a physiologic effect that antagonizes another drug.
Drug holidays do not help prevent withdrawal symptoms. Those will develop if the drug is taken regularly.
The optic nerve is ______________ to the optic tract.
anterior
Impaired MLFs lead to failed adduction on the _____________ side.
ipsilateral
The MLF connects the ipsilateral medial rectus with the contralateral lateral rectus. If you disrupt the connection, then when the contralateral lateral rectus is abducted, then the ipsilateral medial rectus will not receive the proper adduction signal and fail to join the eye.
The inferior rectal vein (in which hemorrhoids are painful) drains to ______________.
the internal pudendal vein
The superior rectal vein drains to the inferior mesenteric vein.
Adrenal crisis (from Addison’s disease or adrenal infarction) requires what two treatments?
- IV fluids (because the patient will likely be hypotensive secondary to aldosterone deficiency)
- Glucocorticoids such as dexamethasone or hydrocortisone (to replace the missing cortisol)
Aortic stenosis is heard at the _________________.
right sternal border
Churg-Strauss disease is also called ________________.
eosinophilic granulomatosis with polyangiitis
Churg-Strauss presents with what symptoms?
- Adult-onset asthma (eosinophilia)
- Polyneuropathy (vasculitis of small or medium vessels)
- Eosinophilia
- Antibodies against neutrophil myeloperoxidase
(I don’t know why this helps me remember it, but churG-strAUSS reminds me of the statistician Gauss of the Gaussian distribution. The Gaussian distribution is a bell curve which looks somewhat like a bi-lobed eosinophil. Also, the slumped edges of a normal distribution look like limp extremities –this can help you remember polyneuropathy.)
In the developed world, the most common cause of hepatic abscess is __________________.
hematogenous spread of bacteria
If a patient has colon cancer but denies changes to bowel habits, then the mass is likely in the ________________.
ascending colon; a mass in the sigmoid or descending colons would produce symptoms with defecation
Give a brief description of Sarcoptes scabiei.
- A mite transmitted by person-to-person contact
- Produces eryethematous papules with crust on top
- Type IV hypersensitivity reaction leads to delayed pruritus –often worst at night
- Typically presents on the flexor folds of the upper extremity
_____________ inhibits alcohol dehydrogenase.
Fomepizole
Disulfiram inhibits the second enzyme in the metabolism of alcohol: aldehyde dehydrogenase.
Inhibiting the enzyme _______________ raises risk of cholesterol gallstones.
cholesterol 7 alpha-hydroxylase
This is the first enzyme in the bile-synthesis pathway. Inhibiting the creating of bile means there will be a higher cholesterol : bile ratio in the gallbladder with a higher likelihood of precipitation.
If a patient is a high-risk surgery patient, then _________________ can be offered to treat cholesterol gallstones.
ursodeoxycholic acid (a bile acid supplement)
True or false: quick weight loss decreases the risk of cholecystitis.
False. Decreased weight loss would likely entail decreased caloric intake. Eating less would mean more cholestasis for the gallbladder so an increased risk of gallstones.
Explain how glutamine helps maintain serum pH.
In the proximal tubule cells, glutamine is broken down to NH3 and glutamate. The NH3 is secreted into the lumen and then trapped upon binding H+. NH4+ is then excreted.
What anion will be increased in the urine of someone with DKA?
Phosphate
Bicarb levels are lower in the serum, so bicarb cannot be used as a buffer. In the urine, PO4 can help capture the excess protons. Thus, more PO4 will be excreted.
Etoposide blocks which enzyme?
Topoisomerase II
Think of the TWO strands of hair grasped by Rapunzel or the word eTWOposide.
List the three most common causes of hypoglycemia in a type 1 diabetic.
- Decreased food intake
- Increased insulin dose
- Exercise
Impairment in which protein systems has been shown to lead to Alzheimer’s and Parkinson’s?
Ubiquitin
Enterococcus bacteremia is common after what kinds of procedures?
Cytoscopy (looking through cameras to the bladder) or anything involving the gallbladder or heart
(Think of the Sketchy protesters with the sign “do U heart trees?” to help remember that Enterococcus commonly colonizes the urinary tract, the heart, and the biliary tree.)
Kawasaki’s disease can present with _____________ and erythema of the hands and feet.
swelling
If you’re calculating the number needed to treat (or harm), then it’s best to ___________________.
calculate the RR of the control and the intervention in percentages and then calculate the difference
So if the RR in the intervention is 45% and the RR in the control is 70%, then the number needed to treat is 4 (because 1/.25 = 4).
Other than the obvious signs like clenched fist or opisthotonus, what is a presenting sign of neonatal tetanus?
Difficulty feeding
The masticatory muscles (involved in the suckling response) will become spastic and the child will not be able to suck.
What kind of receptor is defective in familial hypocalciuric hypercalcemia?
GPCR
The G-protein inhibits the release of PTH when binding calcium and allows the release of PTH when it is not binding calcium.
The main antibody response to influenza vaccination is directed against what protein?
Hemagglutinin
Which part of the brain is injured in those with persistent central DI?
The hypothalamic nuclei!
If the central DI is transient, then the damage was likely to the posterior pituitary or the pituitary infundibulum. Persistent central DI suggests damage to the hypothalamic nuclei because the axons can release ADH from the infundibulum if it’s damage to the pituitary.
Tricky.
To which area of the genome are primers made?
The area flanking the exon you’re intending to amplify as well as the start of the exon
What is cDNA?
Complementary DNA
It is the DNA made by reverse transcriptase that is complementary to the RNA genome.
What is supportive psychotherapy?
It is a system of therapy designed to help individuals cope with chronic psychiatric illness by “bolstering psychological defenses.” Not sure what it means beyond that.
The best therapy for _______________ is cognitive behavioral therapy.
specific phobias
Why do the kidneys shrink in obstructive urinary retention?
The increased hydrostatic pressure pushes on the parenchyma, leading to pressure atrophy.
Explain the relationship between blood/gas partition coefficient and potency of inhaled anesthetic.
Trick question: there is no relationship.
Potency correlates with the minimal alveolar concentration (MAC) needed to anesthetize 50% of patients. Having a high blood/gas coefficient, meanwhile, just means that the anesthetic is more soluble in the blood and it will take longer to reach MAC.
Explain the best screening test for rheumatoid arthritis.
You might be tempted to guess that rheumatoid factor (anti-IgG IgM) is the best screening test for RA. Not so. While it is present in most people with RA (high sensitivity), it is also present in 10% of healthy people (low specificity). Thus, its clinical utility is limited.
Anti-citrullinated peptides, however, have a high specificity for RA. Inflammation causes arginine to be converted to citrulline. Anti-CCP antibodies (as they’re also called) are strongly suggestive of RA.
