UWorld Test 5/19/2014

Question 1

Cleft lip and cleft palate results from?

Answer 1

Failure of fusion of the two lateral maxillary prominences with the interaxillary segment (aka medial nasal prominence) during embroyogenesis. Cleft palate results when the palatine shelve of the maxillary prominence fail to properly fuse with one another or with the primary palate

Question 2

What is bupoprion, major side effect, toxicity?

Answer 2

Increase dopamine and NE with greater effect on dopamine. Toxicity: stimulant effects like tachycardia, insomenia, also headache, SEIZURES IN BULIMIC PATIENTS. Contraindicated in patients with siezure disorder or with current/past history of bulimia/anorexia nervosa

Question 3

What drugs cause seizures

Answer 3

with seizures, I BITE my tongue - INH (vit B6 deficiency), Bupropion, Impinem/cilastatin, Tramadol, Enflurane, Metoclopramide

Question 4

What is phenoxybenzamine, what is it used for? What is phenolamine

Answer 4

Phenoxybenzamine: Irreversible alpha blocker. Give preoperatively to patients with pheochromocytoma to prevent catecholamine (hypertensive) crisis. Toxicity: orthostatic hypotension, reflex tachycardia. Phenotalmine: reversible alpha blocker. Give to patients who eat tyramine containing foods on MAO inhibitor.

Question 5

Right nasal hemianopia can be caused by?

Answer 5

Impingment on peri-chiasm of uncrossed fibers. For example, calficiation of the internal carotid artery can laterally impinge on the optic chiasm.

Question 6

What is Chediak Highashi syndrome

Answer 6

Defect in lysosomal trafficking regulator gene (LYST), microtubule dysfunction in phagosome-lysosome fusion A/R. Sx: Recurrent pyogenic infections by staph and strep, partial albinism, peripheral neuropathy, progressive neurodegeneratino, infilitrative lymphohistiocytosis. Findings: Giant granules in neutrophils and platelets. Pan cytopenia, mild coagulation defects

Question 7

What are the most common causes of acute pancreatitis

Answer 7

Alcohol and gallstones

Question 8

What are some indicators of chronic alcohol consumption/alcoholic hepatatitis

Answer 8

AST:ALT ratio >2, macrocytosis, elevated GGT - indirect indicators of chronic alcohol consumption.May be due secondary to bad diet (low Vit B12 or folate) but can also be unrelated to diet/ related to toxic effects on the bone marrow.

Question 9

What is a major pathogen in burn patients?

Answer 9

Pseudomonas aeruginosa

Question 10

What drugs are effective against pseudonomas

Answer 10

Few specific penicillins (ticarcillin, piperacillin), cephalosporins (ceftazidime, cefepime). Some aminoglycosides (amikacin, tobramycin, gentamicin), fluoroquinolones (ciprofloxacin, levofloxcacin), and carabanepams (impinem, meropenem), monobactam (aztreonam) are also effective.

Question 11

Infection with mycoplasma pneumonaie causes what kind of blood pathology?

Answer 11

Causes mild anemia. This is because ther eis antigenic similarity between M pneumonia cell membrane antigens and RBC cell membrane antigens. The antibodies against this antigen is called “cold agglutins” because they cause RBCs to agglutinate in lower temperatures. Can also cause Steven johnson sydrome, rarely

Question 12

What is the most common cause of hyatid cysts? Where do they occur? What should you avoid doing?

Answer 12

Echinococcus granulosis - tapeworms. Occurs in indivduals frome endemic regions (like australiz, med countries, middle east, iceland, NZ), or from SW US with sheep and dog exposure (these animals participate in tapeworm life cycle). Most commonly occur in the liver. do not aspirate. spilled contents may cause anaphylaxis.

Question 13

What is the DOC for long term prevention of recurrent venous thromboembolism

Answer 13

Warfarin/coumadin. Monitor with PT. Inhibits vit K dependent glutamate carboxylation of glutamic acid results in 2, 7, 9, 10.

Question 14

Parvoviruses are what kind of DNA viruses

Answer 14

Single stranded, non-enveloped DNA Viruses

Question 15

Aplastic crisis in patients with Sickle cell is usually caused by?

Answer 15

Aplastic crisis - persistently decreased reticulocyte count/insufficient response to anemia. Due to parvovirus infection which has a predilication for the bone marrow. Destroys erythroid precursor cells by this virus and dimishes the number of reticulocytes available to replace deformed/removed erythrocytes

Question 16

What is the function of 16s rRNA in prokaryotic ribosomes?

Answer 16

Found in 30S ribosomal subunit. 16s rRNA contains sequence complementary to the Shine Delgarno equence on mRNA. Binding of these two is necessary for initiation of protein translation.

Question 17

What liver specific enzyme facilities the use of TAG breakdown products as intermediates in energy generation and glucose synthesis?

Answer 17

Glycerol kinase

Question 18

Respiratory distress, diffuse neuro impairment like confusion, upper body petechial rash within days of several long bone fractures is indicative of?

Answer 18

Fat Embolism syndrome. See multiple fat emboli in the pulmonaryy vascular. Stains black with osmium tetroxide.

Question 19

What are the topical vitamin D drugs used to treat psoriasis? What is the MOA?

Answer 19

Calcipotriene, calcitriol, tacalcitol bind to vitamin D receptor and INHIBIT kertinocyte proliferation, stimulate keritoncyte differentiation.

Question 20

Wht is the MOA of 6 mercaptopurine and azathioprine. 6 mercaptopurine is metabolized by?

Answer 20

Azathioprine is a metabolic precursor of 6MP - cytotoxic purine analog. Decreases de novo purine synthesis. Metabolized by xanthine oxidase. If you use allopurinol, a xanthine oxidase inhibitor, must adjust dosage of 6 mercaptopurine

Question 21

Why should you wait for a couple of weeks between stopping an MAO inhibitor and starting an SSRI?

Answer 21

Combined MAO inhibitor and SSRi can cause too much serotonin and can lead to serotonin syndrome. Need to wait a couple of weeks for MAO to be regenerated and then can start SSRI

Question 22

Histologic hallmark of rickets?

Answer 22

Unmineralized matrix, widened osteoid seams = osteiod accumulation around trabeculae. Clinical - bowed legs, rachicitc rosary (bony prominence at costochondral junction), indendentaions in lower ribs (Harrion’s sulci), softening of skul (craniotabes), growth regardation

Question 23

Excretion of large amounts of fructose in urine is indicative of?

Answer 23

Essential fructosuria

Question 24

In patients with esential fructosuria, what is the disroder? Also, how is fructose then metabolized?

Answer 24

Fructokinase deficiency (inability to convert fructose to fructose 1 phosphate). Large amounts excreted in urine. Fructose can be converted by hexokinase to Frcutose 6 phosphate, a glycolytic intermediate

Question 25

Methylomalonic aciduria results from?

Answer 25

= increased levels of methymalonyl CoA - due to deficiency of methylmalonyl CoA mutase (isomerization reactions that transforms methylmalonyl CoA to succinyl CoA that can enter the TCA cycle)

Question 26

Most patients with acute tubular necrosis expeirence what in their recovery?

Answer 26

Re-epitheliization of tubules

Question 27

What is an impaired upward gase called?

Answer 27

Parinaud syndrome

Question 28

Parinaud syndrome is most consistent with tumor of what region?

Answer 28

Pineal tumors

Question 29

Pineal region is the most common location of?

Answer 29

Brain germinomas which are histologically similar to testicular seminomas

Question 30

What is the MOA of calcineurin. Where is it found in?

Answer 30

Found in T cells. Once T cells are setimulated, calcineurin is activation which dephosphorylates NFAT-P. NFAT then enters the nucleus where it binds to the promoter of IL-2. IL-2 stimulates the growth and differentiation of T cells.