Qbank 4 Flashcards
Proximal 1/3 of ureter receives blood supply from where?
Renal artery
Vitiligo: what causes loss of pigment?
- loss of melanocytes in skin
- autoimmune association.
Mechanism of antibiotic that is used for S. aureus skin infections, esp. MRSA, bacteremia, endocarditis, and VRE. Side effects?
- lipopeptide that disrupts cell membrane of gram positive cocci
- side effects: myopathy and rhabdomyolysis
Medications that can cause seizures?
buproprion, clozapine, isoniazid, imipenem, fluoroquinolones
Gardener’s mydriasis: dry mouth, flushed, hot temperature, double vision, dilated pupils, tachycardia. Cause? Antidote?
- Jimson weed poisoning, similar to atropine poisoning
- sympathethic effects due to blockade of muscarinic receptors
- treat with physostigmine
Mechanism of urinary incontinence in normal pressure hydrocephalus?
-hydrocephalus causes distortion of paraventricular white matter. Loss of cortical inhibition of sacral micurition center (S2-S4) leading to urge incontinence.
Lung hamartomas usually contain?
-disorganized cartilage, adipose, fibrous tissue
presentation of glucagonoma.
- Diabetes
- GI complaints: pain, diarrhea, anorexia
- Necrolytic migratory erythema: red papules/plagues that grow and coalesce. Leave central clearing that is bronze and indurated with peripheral scaling an blistering
- Anemia
- depression
motile gram positive rod with narrow zone of hemolysis. Grows well at refrigeration temperatures. What bacteria? What immune response is most effective against it?
-Listeria
-T cell mediated immunity
-listeria is intracellular, it produces listeriolysin
O which allows it to escape phagosome into the cytosol.
List intracellular bacteria.
obligate: rickettsia, chlamydia, coxiella
facultative: salmonella, neisseria meningitidis, brucella, mycobacterium, listeria, franciscella, legionella, yersinia pestis
Person with Strain of tb that has decreased activity of intracellular catalase-peroxidase. Which anti-TB drug will not work?
- Isoniazid
- bacterial catalase peroxidase needed to convert INH to active metabolite
Why is methadone drug of choice for treating heroin addiction?
- long half life, good bioavailability
- able to have continuing suppression of withdrawal symptoms
Amino acid transamination requires what cofactor?
B6
-transamination occurs between amino acid and alpha-keto acid. Amino group from amino acid transferred to a-keto acid, and a-keto acid becomes an amino acid
Abdominal aortic aneurysm. Most common cause?
-atherosclerosis. Atheromas weaken underlying media.
Where do Viridians Streptococci bind on damaged heart valves?
-S. sanguinis makes dextran, which bind to fibrin platelet aggregates on damaged heart valves. Must have endothelial damage leading to fibrin platelet aggregates for binding.
Atelectasis, where does trachea deviate? Causes of atelectasis? X-ray findings?
- Towards the side of the lesion
- cause: bronchial obstruction, infection
- x-ray: opacification of lung
Management of drug induced parkinsonism by antipsychotics.
Rx: benztropine (antimuscarinic) or amantadine
-dopamine agonist may worsen psychosis
Symptoms are caused by blockage of D2 receptors in the nigrastriatal pathway
Mechanism of action of the following antifungals:
- nystatin
- flucytosine
- azoles
- terbinafine
- caspofungin
- griseofulvin
- nystatin: same as amphotericin. binds ergosterol and forms pores. Causes leakage of electrolytes
- flucytosine: inhibits DNA and RNA biosynthesis by conversion to 5-FU by cytosine deaminase
- azoles: inhibits cyp450, preventing conversion of lanosterol to ergosterol
- terbinafine: inhibits fungal enzymes squalene epoxidase (ergosterol synthesis)
- caspofungin: inhibits cell wall synthesis by inhibiting synthesis of beta-glucan
- griseofulvin: interfere with microtubule function
Cell type that stains positive for synaptophysin
Neurons
Treatment of congenital adrenal hyperplasia
-low dose glucocorticoids. Suppresses ACTH secretion and decreases stimulation of adrenal cortex so that will decrease androgen production
Niacin can by synthesized from which amino acid?
tryptophan
what cranial nerve can be injured in a transtentorial/uncal herniation? What artery?
CN III
PCA
What artery can be compressed in subfalcine herniation?
ACA
Define the following: Berkson bias, Hawthorne effect, Pygmalion effect.
- Berkson bias: study population selected from hospital is less healthy than general population
- Hawthorne effect: change in behavior in subjects as results of being aware they are being studied
- Pygmalion effect: Researcher’s belief in efficacy of treatment changes outcome of that treatment. E.g. More likely to document positive results if expect positive results.
Urine smells like burnt sugar. What enzyme is deficient? What enzymes can’t be degraded? Supplement with what vitamin would lead to improvements?
a-ketoacid dehydrogenase
isoleucine, leucine, valine: branched amino acids
-thiamine, is a cofactor for the enzyme.
Which vein has the most different oxygen content compared to aorta?
Carotid Sinus
- because there is high myocardial oxygen demand
- heart extracts oxygen more efficiently than any other tissue
Hyperacute transplant rejection is what type of hypersensitivity?
Type II -due to preformed antibodies in the host. Anti ABO or anti HLA (IgG antibodies)
- see gross mottling and cyanosis
- arterial fibrinoid necrosis and capillary thrombosis
Parasympathetics to lacrimal, submandibular, sublingual glands originate from which nerve?
Facial
At what steps do the following diseases of collagen synthesis occur?
- Osteogenesis imperfecta
- Ehler-Danlos syndrome
- Scurvy
- Osteogenesis imperfecta: inside fibroblasts cytosol, inability of form triple helix after glycosylation at RER
- Ehlers-Danlos: usually problem in cross linking collagen fibers after it has been excreted into extracellular matrix
- Scurvy: problems with hydroxylation of specific proline and lysine residues at RER
Dark skin patches with ulcerated appearance and occasional necrotic center in chemotherapy patient. What bacteria?
Pseudomonas Aeruginosa
-Ecthyma gangrenosum
Ab pain, nausea, vomiting, lacrimation, yawning. Muscle aches, dilated pupils, hyperactive bowel sounds, piloerection. What is patient withdrawing from?
Heroin/opioids.
- does not result in seizures like alcohol or benzo withdrawal.
- yawning and lacrimation are fairly specific to opioid withdrawal
Dysthymic disorder
chronic low intensity mood disorder that responds well to antidepressants
-symptoms less severe than major depressive disorder but must be present for at least 2 years
Sweat glands in axilla and pubic area are what type? Rest of body?
- apocrine glands in axilla and pubic area. Secrete membrane bound vesicles into hair follicles
- eccrine/merocrine glands are through rest of body, secrete directly to skin surface
Periorbital and temporal pain, with lacrimation, nasal congestion and ptosis. Lasts about 30 mins and classically occurs a few hours after going to sleep. What type of headache?
Cluster
-affects males more than females. Usually have 1 year interval of being headache free
Adverse effects of protease inhibitors?
- lipodystrophy
- hyperglycemia
- inhibition of cyp450
What is the best indicator of the severity of mitral regurg?
S3 sound, indicating left ventricular overload
besides influenza, what other virus has segmented genome?
rotavirus
Why does squatting improve tetralogy of Fallot?
Increases systemic vascular resistance and decreases right to left shunt, improving cyanosis.
What determines ventricular contraction rate in Afib?
AV node refractory period
What causes hypocalcemia in patient who receives multiple packed red blood cells?
Citrate added to blood chelates calcium
What provides the fastest reversal of warfarin’s effects?
fresh frozen plasma
-Vit K takes more time
In Hirschprung disease, where would you sample for biopsy, the narrow or dilated portion? How deep would you biopsy?
- Narrow portion, up to submucosa where the Meissner’s plexus is. It is the most superficial layer can see missing ganglion cells
- Auerback’s plexus is in muscular layer
Fidaxomicin
antibiotic for C dif with minimal systemic absorption
What contributes to gallstones formation in Crohns disease?
bile acid wasting because not absorbed in ileum. Result is there is less bile acid in gallbladder and increased cholesterol to bile acid ratio.
Preferred med for absence seizures with clonic-tonic seizures.
valproate acid
What is the single most important risk factor for aortic dissection?
Hypertension
Best way to prevent neonatal tetanus?
Vaccination of mother with tetanus toxoid during pregnancy. Immunized mother would transfer IgG antibodies to fetus
How to prevent toxicity by acyclovir?
Hydration
-if not hydrated, can cause obstructive crystalline nephropathy and acute renal failure
What can be used to test coronary vasospasm for Prinzmetal Angina?
Ergonovine stimulates alpha adrenergic and serotonergic receptors. Low doses causes vasospasm in patients with Prinzmetal’s angina.
Which acethylcholinesterase inhibitor can cross the BBB?
physostigmine
What serum marker is elevated with temporal arteritis?
ESR
Defective transport of cysteine ornithine lysine arginine across intestinal and renal tubular epithelium. Manifestation?
cysteinuria. Only clinical manifestation is recurrent kidney stones.
What drug can be given to control symptoms of carcinoid tumor?
Ocreotide.
22 year old woman with severe weakness of her left leg, beginning 2 days after fiancee broke of engagement. No PE findings. What disorder?
Conversion disorder. Unconscious manifestations of neurological symptoms, especially after life stress.
Uremic platelet dysfunction.
Uremic toxins in renal failure patients cause qualitative platelet disorder. Impaired aggregation and adhesion. Normal labs except for prolonged bleeding time.
biologic agent suffix meanings
- nib: kinase inhibitor
- mab: monoclonal antibody
- cept: receptor molecule
Hematogenous osteomyelitis commonly affects children. What part of the bone does it usually affect?
Metaphysis of long bones
Sudden right sided weakness. Uncontrolled HTN. No abnormalities on CT. 4 weeks later, imaging shows small cavitary lesion in left internal capsule. Condition caused by?
Lacunar infarcts. In acute setting small infarct size may not show up on CT scan. Most often due to hypertensive arteriolosclerosis
Common presentation of right sided colon cancers?
Iron deficiency anemia due to ongoing blood loss and systemic symptoms
Mechanism of Cilostazol
Platelet phophodiesterase inhibitor. Increases cAMP and prevents platelet aggregation. Also causes vasodilation. Used to treat peripheral arterial disease/claudification.
Aspiration of hydatid cysts due to echinococcus can cause what?
-often affects the liver
spilling over of cysts content into peritoneum can cause anaphylactic shock
What neuro pathways are affected by B12 deficiency?
- dorsal columns
- descending lateral corticospinal tracts: upper neuron signs
- peripheral nerves
In AV block, what becomes response for pacing the ventricles?
AV node, when conduction between SA and AV node is impaired. Heartbeat at 45-55 beats/min
-if anything below the AV node and bundle of His took over pacemaking function, would have beats ~20beats/min
The ductus arteriosus is derived from which aortic arch?
6th
Which site on tRNA is for binding amino acid? Which site for anticodon?
- 3’ CCA site for binding amino acid
- opposite arm has anticodon
Akathisia
subjective restlessness with an inability to sit still.
-side effect of antipsychotics
Ressortment vs recombination
Ressortment refers to mixing of genome segments in segmented viruses.
-recombination involves crossing over of two double stranded DNA molecules
Bilateral lower lobe infiltrates after cruise. Hyponatremia. High fever, confusion, watery diarrhea. Sputum gram stain shows many neutrophils, but few or no organisms. What organism?
Legionella.
Over a year, a nontender cervical lymph node that fluctuates in size. What lymphoma?
follicular cell lymphoma.Indolent clinical course with remissions and recurrences.
Elevated alkaline phosphatase of unclear origin can be followed up with what lab test?
y-glutamyl transpeptidase. GGTP. Will help elucidate whether ALP elevation was of liver or bone origin.
What are levels of testosterone and LH in Klinefelter’s syndrome?
Low testosterone and elevated LH. Usually the leydig cells are also dysfunctional
