Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Step 1 > UWorld Review > Flashcards

UWorld Review Flashcards

0
Q

What is the significance of the pol gene mutation?

A

Confers HIV resistance to protease inhibitors and nucleoside and non-nucleoside reverse transcriptase inhibitors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Name three drugs that universally enhance the cytochrome P-450 pathway.

A

Rifampicin, phenobarbital, phenytoin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Ticlopidine (an ADP antagonist) is commonly associated with what side effect?

A

Neutropenia with fever and oral ulcers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name three causes of B12 malabsorption (not including pernicious anemia).

A

Pancreatic insufficiency, ileal disease, and intestinal bacterial overgrowth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the safest anticoagulation treatment for a pregnant woman with DVT?

A

Heparin (Warfarin and Coumadin are teratogenic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the function of 2,3-BPG in erythrocytes?

A

2,3-BPG binding allosterically decreases the affinity of hemoglobin for oxygen, enabling the delivery of oxygen to tissues even when PO2 is low.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the mechanism of action of desmopressin?

A

Stimulates release of factor VIII and vWF from endothelial cells. Used to treat hemophilia A.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How does lead poisoning cause anemia?

A

Inhibition of ALA dehydratase, the enzyme that incorporates iron in heme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What region of the lymph node is populated by T cells?

A

Paracortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Extramedullary hematopoiesis is most frequently seen in what category of disease?

A

Chronic hemolytic anemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the function of retinoblastoma (Rb) protein?

A

Phosphorylation of Rb renders it inactive and releases E2F transcription factor. This permits the transition from G1 to S phase of the cell cycle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the name of a subcutaneous fungal infection commonly transmitted to gardeners following a thorn prick?

A

Sporotrichosis, a mycosis caused by Sporothrix schenckii

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the major adverse effect associated with succinylcholine?

A

Hyperkalemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are three signs of mitochondrial encephalomyopathy?

A

Neuromuscular lesions, ragged red skeletal muscle fibers, lactic acidosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the most common cause of osteomyelitis in children?

A

Staph aureus (2nd most common is group A strep)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the function of lecithinase (alpha toxin), a toxin produced by C perfringens?

A

Catalyzes the splitting of phospholipids. Causes hydrolysis of cell membranes leading to cell lysis, tissue necrosis, and edema.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the function of protein A made by staph aureus?

A

Binds the Fc region of IgG, preventing opsonization and complement-mediated destruction of the bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What three drugs are commonly used for MRSA bacteremia?

A

Vancomycin, daptomycin, linezolid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What marker is elevated in malignant ovarian epithelial tumors?

A

CA-125

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the characteristics of endocarditis caused by Strep bovis?

A

Subacute onset, no preexisting valve abnormality, associated with colon cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What infectious agent is most commonly responsible for subacute bacterial endocarditis following dental work?

A

Strep viridans

21
Q

What is the etiology of maple syrup urine disease?

A

Defective breakdown of branched chain amino acids (leucine, isoleucine, valine) due to mutation in branched-chain α-ketoacid dehydrogenase.

22
Q

What are the five cofactors required for pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, and branched-chain α-ketoacid dhydrogenase?

A

Thiamine pyrophosphate, lipoate, coenzyme A, FAD, NAD (Tender Loving Care For Nancy)

23
Q

How does defective absorption of tryptophan cause the symptoms seen in Hartnup disease?

A

Tryptophan is a precursor required for the formation of nicotinic acid (niacin), serotonin, and melatonin. Niacin deficiency causes photosensitivity and neurological sx. Malabsorption of tryptophan causes aminoaciduria.

24
Q

What are the symptoms of vitamin E deficiency?

A

Degeneration of spinocerebellar tracts, dorsal column of the spinal cord, and peripheral nerves. Manifests as ataxia, dysarthria, loss of proprioception and vibration sense.

25
Q

When treating meningitis with empiric ceftriaxone, ampicillin should be added to cover what possible bacterial agent?

A

Listeria

26
Q

What are the functions of HIV proteins gp120 and gp41?

A

gp120 binds to CD4 receptors on target human cells

gp41 is a transmembrane protein that anchors gp120 and mediates the fusion of the virus with the target cell

27
Q

What is a Krukenberg tumor?

A

A metastatic tumor in the ovarian stroma that originated from a gastric carcinoma. It is made up of mucin-producing, signet-ring neoplastic cells.

28
Q

What drugs have been implicated in drug-induced lupus?

A

Hydralazine, isoniazid, procainamide, minocycline, quinidine

29
Q

What is the measure of blood solubility of an anesthetic and how does it relate to the speed of CNS effect (induction)?

A

Blood/gas partition coefficient.
Large blood/gas partition coefficient = high solubility in the blood = longer time to saturation = slower CNS effect induction

30
Q

What are the symptoms of graft vs. host disease?

A

Damage to the skin (desquamation), liver (jaundice, elevated LFTs), and GI tract (diarrhea, GI bleeding, cramping, ileus).

31
Q

What are the symptoms of niacin (B3) deficiency?

A

Pellagra: dermatitis, diarrhea, dementia. Niacin is an essential component of NAD and NADP. It can be obtained from the diet or synthesized from tryptophan.

32
Q

In what setting would you see hyperosmotic volume contraction?

A

Hyperosmotic volume contraction = loss of free water exceeding the loss of electrolytes.
Seen in diabetes insipidus.

33
Q

What neurotransmitter is implicated in the development of opioid tolerance?

A

Glutamate: activates NMDA receptors, leading to phosphorylation of opioid receptors and subsequent opioid tolerance

34
Q

Which histones make up the nucleosome core?

A

H2A, H2B, H3, H4

H1 lies outside the nucleosome and facilitates the packaging of nucleosomes into compact structures.

35
Q

What area of the brain maintains circadian rhythms?

A

The suprachiasmatic nucleus of the hypothalamus.

36
Q

What are the pharmacologic characteristics of drugs that are cleared by the liver?

A

High lipophilicity, high volume of distribution

Lipophilic drugs also have better CNS penetration

37
Q

What mutation is most commonly implicated in cystic fibrosis?

A

CFTR gene codes for a membrane protein. The mutation is usually a three nucleotide deletion resulting in the loss of phenylalanine at position 508. The mutation causes abnormal protein folding and failure of glycosylation.

38
Q

What are the cardiac manifestation of the tetralogy of Fallot?

A

1) pulmonic stenosis 2) VSD

3) right ventricular hypertrophy 3) overriding aorta

39
Q

What are the five T’s responsible for cyanotic heart disease?

A

Tetralogy of Fallot, Tricuspid atresia, Transposition of the great vessels, Truncus arteriosus, Total anomalous pulmonary venous return

40
Q

What is the triad of Wernicke encephalopathy?

A

Confusion, ataxia, and ophthalmoplegia

Infusion of glucose w/o thiamine can precipitate Wernicke encephalopathy (damage to mamillary bodies)

41
Q

What is the risk associated with taking valproate during pregnancy

A

Increased neural tube defects

42
Q

What is the risk associated with taking lithium during pregnancy?

A

Ebstein’s anomaly: downward displacement of the tricuspid valve (“atrialized right ventricle”)

43
Q

Why are multivitamins contraindicated with levodopa therapy?

A

B6 increases peripheral metabolism of levodopa and decreases its effectiveness

44
Q

What is the function of leptin?

A
  • decreases the production of neuropeptide Y, an appetite stimulant.
  • stimulates production of POMC. POMC is cleaved into α-MSH, which inhibits food intake.
45
Q

What disease is associated with cystic degeneration of the putamen?

A

Wilson’s disease

46
Q

What mutation is associated with Lynch syndrome?

A

Mutation in a gene responsible for DNA mismatch repair

Autosomal dominant and predisposes to colon cancer

47
Q

What three components are required to make nitric oxide?

A

Arginine, NADPH, O2

48
Q

What is the most common location for intracranial schwannomas?

A

Cerebellopontine angle

49
Q

Which two antiarrhythmics are most selective for ischemic myocardium and therefore most useful in arrhythmia following MI?

A

Lidocaine and amiodarone

50
Q

What is the diagnostic utility of gamma-glutamyl transpeptidase?

A

Distinguish between liver and bone in the setting of elevated alk phos. Gamma-glutamyl transpeptidase is seen in liver but not bone disease.

51
Q

What are the normal values for PO2, PCO2, and A-a gradient?

A

PO2 = 100, PCO2 = 40

A-a gradient = 10-15

Step 1 (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions