NBME 2

Question 1

Tumor necrosis factor is the primary mediator of host responses initiates by lipopolysaccharide (LPS) and leading to septic shock. LPS mediated activation of transcription most likely depends on what transcription factors?

Answer 1

NFKB

Question 2

What is the principal site of therapeutic action of aspirin in the blood vessel?

Answer 2

Dilation of the muscle layer

Question 3

The largest collection of neurons in the CNS that use norepinephrine as a neurotransmitter is found where?

Answer 3

Locus cereuleus

Question 4

A 6 yr old boy says his left ear hurts. His mother says he has been tugging the ear. The external canal and tympanic membrane appear normal, but the tympanic membrane does not move when pressure in the nasopharynx is increased. What is the most likely cause of these findings?

Answer 4

Auditory tube obstruction

Question 5

A 20 yo woman develops severe pain and erytheme over sun-exposed skin and large bullae over her shoulders while vacationing in Florida. Skin testing results in major positive rxn to methylparaben, which is often used as a preservative in medicines. A sunscreen containing, which of the following is contraindicated in this pt?

Answer 5

salicylates

Question 6

54 yo woman with DM2 well controlled with oral hypoglycemic agents comes to the physician because of a 2 week history of swelling in her left knee. She tells the physician that her knee is very stiff when she awakens in the morning and at bedtime. The pain and stiffness worsens with exertion. Low-dose ibuprofen results in incomplete relief. Why is a larger dose of ibuprofen more appropriate as tx?

Answer 6

Oral hypoglycemic agents interfere with protein binding of ibuprofen

Question 7

37 yo man develops a spiking fever in the intensive care unit after an operation to control an abdominal hemorrhage. Evaluation does not show a focal infection. Therapy with a broad-spectrum cephalosporin is initiated. After 3 days of antibiotic therapy, the pt has abdominal pain and profuse watery diarrhea. examination of stool for ova and parasite is negative. Stool tests positive for Clostridium difficile Ag. What is the most appropriate therapy?

Answer 7

Amphotericin

Question 8

Based upon this picture of lung tissue, what was the occupation exposure?

Answer 8

Asbestos

Question 9

Male pt comes to physician because of a 2 day history of burning with urination. He tells the physician that he had an affair while on a business trip 2 weeks ago. The next the pt’s wife calls and request to know the Dx made of her husband. What is the physician’s correct response?

Answer 9

I am sorry but I will need your husband’s permission to discuss his care with you?

Question 10

Pt swallows 100mL of carbon tetrachloride (CCl4) in an attempted suicide. What is the likely outcome?

Answer 10

Severe hepatotoxicity as a consequence of damage to the plasma membranes

Question 11

A genetic element is found to contain several genes and to catalyze its own movement within and between chromosomes. Inverted 35-nucleotide repeats are present at the ends of this genetic element. This genetic element in hepatocytes is incapable of replicating independently. Based upon this description this genetic element is best characterized as what?

Answer 11

Plasmid

Question 12

55 yo male with DM presents with burning dysesthesias over the lateral aspect of his left lower leg. Capsaicin containing cream is effective in alleviating the symptoms. The substance most likely to have caused the dysesthesias is?

Answer 12

Neuropeptide Y

Question 13

2 day old neonate is transferred to the neonatal intensive care unit because of tachypnea and intense cyanosis. There is a prominent lift and a soft, systolic murmur is heard along the left sternal border. S1 is loud at the lower left sternum. X-ray film of the chest shows a normal heart size and pulmonary vascular pattern. Echocardiography shows the aorta lying anterior and to the right of the pulmonary artery. What is the likely Dx?

Answer 13

Transposition of the great vessels

Question 14

Female, 32 yo pt presents onset of recurrent headaches. She develops nausea, vomiting, weakness, abdominal pain and easy bruising. Labs show:
Hb - 6.9 g/dL
Leukocyte count - 15,000/mm3
MCV - 78 um3
Platelet count - 30,000/mm3

she immediately admitted to the hospital. Over the next few days she develops progressive lethargy and lapses into a coma. A peripheral blood smear is likely to show what?

Answer 14

Spherocytes

Question 15

recombinant vaccine used t immunize against HBV infections elicits Ab against which viral protein?

Answer 15

HBsAg

Question 16

Female presents with fever, nausea and acute abdominal pain and tenderness.Lab studies show a neutrophilic leukemoid rxn. A laparotomy and appendectomy are done. What finding will establish the Dx of acute appendicitis?

Answer 16

Mucosal ulceration

Question 17

During 2nd and 3rd trimesters of pregnancy, women have increased levels of circulating glucocorticoids but have few of the cataboloc responses associated with the excess glucocorticoids. What is most likely increased to cause these findings?

Answer 17

Steroid binding proteins

Question 18

59 yo male presents with malaise, fatigue and anorexia since losing his job 3 month ago. Serum gamma-glutamyltransferase (GGT) activity is increased. what is the appropriate question to initiate discussion about alcohol use?

Answer 18

How much do you drink in a typical week?

Question 19

The prevalence of a disease ia half as great in town A than it is in town B, but the incidence of the disease is no different in town A than it is in town B. What explains this finding?

Answer 19

The duration of the disease is twice as long in town B

Question 20

58 yo male presents with blood in urine. He had nephrectomy 10 years ago because of injuries sustained in a motor vehicle a collision. Evaluation shows renal cell carcinoma in his remaining kidney and pulmonary metastases. IL-2 therapy is started. Three weeks later, Ct scan confirms regression of the tumor. What likely caused the regression?

Answer 20

Cytotoxic effects of IL-2 on tumor cells