Uworld Step 1 Qbank

Front 1

What proteins are involved in assembly of gap junctions?

Back 1

Connexins (e.g. connexin-43)

Front 2

What decreases the incidence of neural tube defects?

Back 2

Folate supplementation during early pregnancy (neural tube develops very early in fetal life, when most women may not know yet they are pregnant)

Front 3

What is least affected by outliers?

Back 3

Mode

Front 4

What is the best statistical test to determine significant differences between means of 2+ groups?

Back 4

Analysis of variance (ANOVA): compares the means between the groups relative to the variability within groups and determines whether any of those means are significantly different from one another (null hypothesis: all groups are simply random samples of the same population)

Front 5

What is the sensory loss and weakness of L5 lumbosacral radiculopathy

Back 5

Sensory loss: buttocks, posterolateral thigh, anterolateral leg, dorsal foot

Weakness: Foot dorsiflexion and inversion (tibialis anterior), foot eversion (peroneus), toe extension (extensor digitorum brevis)

Front 6

What mode of inheritance is achondroplasia?

Back 6

Autosomal dominant, with full penetrance

Front 7

What is the most likely side effect of SSRIs when used in recommended doses and without other risk factors?

Back 7

Sexual dysfunction (decreased libido, decreased arousal, anorgasmia in women, increased ejaculation latency in men); occurs in approximately 50% of patients receiving SSRIs and is a frequent cause of nonadherence

Front 8

What deficiency is associated with a high rate of measles complications?

Back 8

Vitamin A (acute measles infection depletes vitamin A stores, resulting in a risk of keratitis and corneal ulceration)

Front 9

What is the typical cause for bladder dysfunction in multiple sclerosis patients?

Back 9

Detrusor overactivity causing a sudden/andor frequent urge to urinate and empty the bladder

Front 10

What does the anilin dye (e.g. carbolfuchsin) in the acid fast stain bind to?

Back 10

Mycolic acids

i.e. used for Mycobacterium and some Nocardia species

Front 11

What are the main cytokines that stimulate B cell growth and differentiation?

Back 11

IL-4 and IL-5

IL-4: B cell growth, isotype switching, stimulates IgE secretion, predisposes to type I hypersensitivity

IL-5: B cell differentiation, stimulates IgA production and eosinophil activity

Front 12

What important viral structural proteins does the measles virus (rubeola) have?

Back 12

Hemagglutinin (cell surface adhesion)

Matrix/fusion protein (viral assembly)

Front 13

Episodic vertigo, tinnitus, and hearing loss: classic diagnosis?

Back 13

Meniere disease: disorder of the inner ear characterized by increased volume and pressure of endolymph (endolymphatic hydrops) thought to be due to defective resorption of endolymph

Front 14

What are common complications of rubella for a pregnant woman?

Back 14

Polyarthritis, polyarthralgia

Front 15

What are common complications of rubella for a fetus?

Back 15

Sensorineural deafness, cataracts, cardiac malformations (e.g. patent ductus arteriosus)

Front 16

What organisms are asplenic patients most at risk for?

Back 16

Encapsulated species (e.g. Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis)

Front 17

What do you treat N. gonorrhoeae (gram-negative intracellular diplococcus) with?

Back 17

Ceftriaxone (3rd generation cephalosporin) and azithromycin (macrolide)

Azithromycin is recommended due to potential resistance against cephalosporins and protection against chlamydia co-infection

Front 18

What second messenger does nitric oxide (NO) increase?

Back 18

intracellular cGMP: leads to vascular smooth muscle relaxation, metabolized by phosphodiesterase

Front 19

What cells do the majority of renal cell carcinomas (RCC) originate from?

Back 19

Epithelium of the proximal renal tubules

Front 20

What does leuprolide do (pulsatile vs. continuous)?

Back 20

Pulsatile: agonist properties, causes a transient rise in LH and testosterone production on initial administration

Continuous: suppresses pituitary LH release and subsequent reduction of testosterone production by Leydig cells

Front 21

What are the effects of spironolactone?

Back 21

Aldosterone receptor agonist

Reduce secretion of K+ and H+ by the collecting tubule

Front 22

What is the mechanism of varenicline?

Back 22

Partial agonist of nicotinic acetylcholine receptors (specifically alpha4 beta2); reduces nicotine withdrawal, prevents nicotine from binding and inducing a reward response

Front 23

What is most consistent with malignancy in lymphadenopathy?

Back 23

Monoclonality of the lymphocyte population

Front 24

What does vitamin B12 serve as a cofactor for?

Back 24

Methylmalonyl-CoA mutase

VItamin B12 deficiency = elevated methylmalonic acid and homocysteine

Front 25

What does DAG (from breakdown of PIP2) activate?

Back 25

DAG stimulates protein kinase C (PKC), which phosphorylates downstream intracellular proteins to produce physiologic effects

PKC is also activated by intracellular calcium, which IP3 increases (its major effect)

Front 26

What is the equation for maintenance dose?

Back 26

Maintenance dose = Cp x CL x tau / F

Front 27

What is the treatment for Lyme disease?

Back 27

Doxycycline (stage 1)

Ceftriaxone (later presentation)

Front 28

What does the suspensory ligament of the ovary, AKA the infundibulopelvic ligament, contain?

Back 28

Ovarian artery (major ovarian blood supply arising from the abdominal aorta entering the ovary at the hilum), vein, lymphatics, and nerves

Front 29

What will increase prevalence but not incidence?

Back 29

Factors that prolong the duration of a disease (e.g. improved quality of care)

Front 30

What is the difference between prevalence versus incidence?

Back 30

Prevalence = measure of those with the disease in the population at a particular point in time

Incidence = measure of appearance of new cases

Front 31

What are risk factors that increase the risk of suicide completion?

Back 31

Stress

Lack of psychosocial support

Psychiatric illness

Substance abuse

Pain

Access to firearms or other means

Front 32

What is the most important virulence factor meningeal pathogens?

Back 32

Bacterial capsules

e.g. K1 capsular antigen in E. coli strains

Front 33

Define heteroplasmy

Back 33

Presence of both normal and mutated mtDNA, resulting in variable expression in mitochondrially inherited diseases

Front 34

How are statins (HMG-CoA reductase inhibitors) metabolized? What statin is the exception?

Back 34

Metablized by P450 3A4 (except pravastatin)

Front 35

What drugs inhibit cytochrome P450?

Back 35

AAA RACKS IN GQ Magazine

Acute alcohol abuse

Ritonavir

Amiodarone

Cimetidine/ciprofloxacin

Ketoconazole

Sulfonamides

Isoniazid (INH)

Grapefruit juice

Quinidine

Macrolides (except azithromycin)

Front 36

Acute radiated iodine exposure.

What's the treatment?

Back 36

Potassium iodide

Front 37

List symptoms of a major depressive disorder

Back 37

SIG E CAPS

Depressed mood

Sleep disturbance

Loss of interest (anhedonia)

Guilt or feelings of worthlessness

Energy loss and fatigue

Concentration problems

Appetite and weight changes

Psychomotor retardation or agitation

Suicidal ideations

Front 38

What is the "chloride shift"?

Back 38

To maintain electrical neutrality, chloride ions diffuse into the RBC to take the place of bicarbonate - causes a high RBC chloride content in venous blood

Front 39

Horner's syndrome

Back 39

Sympathetic denervation of the face

PAM: Ptosis (slight dropping of eyelid, superior tarsal muscle), Anhidrosis (absence of sweating) and flushing of the affect side of the face, Miosis (pupil constriction)

Ptosis, anhidrosis, miosis (rhyming)

Front 40

What is the primary choice of treatment for anaphylactic shock?

Back 40

Epinephrine, due to its ability to reverse all of the pathophysiologic mechanisms of anaphylaxis; stimulation of alpha-1 receptors counteracts vasodilatation of cutaneous and viscera vasculature, increasing BP

Front 41

What is the most probable cause of one-sided kidney atrophy?

Back 41

Renal artery stenosis (RAS); occurs in elderly individuals due to atherosclerotic changes in the arterial intima, or in women of childbearing age due to fibromuscular dysplasia

Hypertension and an abdominal bruit are present

Front 42

Fat embolism syndrome: triad?

Back 42

Hypoxemia

Neurologic abnormalities

Petechial rash

Associated with long bone fractures and liposuction; greater in bilateral femoral fractures (33%) compared to a single long bone fracture (1-3%)

Front 43

What contributes to the rubber-like properties of elastin fibers?

Back 43

Interchain cross-links involving lysine

Elastin is synthesized as a large polypeptide precursor (tropoelastin) composed of 700, mostly nonpolar, amino acids (glycine, valine, alanine); also contains hydroxylated proline and lysine residues

Front 44

Cori disease (type III glycogen storage disease): clinical presentation and deficient enzyme?

Back 44

Hypoglycemia, ketoacidosis, hepatomegaly, muscle weakness, hypotonia

Debranching enzyme (alpha-1,6-glucosidase)

Front 45

Hemodynamic actions of epinephrine

Back 45

HR: dose dependent increase, beta-1

SBP: increase (++), beta-1 and alpha-1

DBP: decrease (low-dose), increase (high-dose), alpha-1 > beta-2

Pretreatment with propanolol eliminates the beta effects of epinephrine (vasodilatation and tachycardia), leaving only the alpha effect (vasoconstriction)

Front 46

Carcinoid syndrome: clinical presentation?

Back 46

Recurrent diarrhea, cutaneous flushing, asthmatic wheezing, right-sided valvular heart disease (tricuspid regurgitation, pulmonic stenosis)

Diagnosis: elevated 24-hour urinary excretion of 5-HIAA, CT/MRI of abdomen and pelvis to localize the tumor

Treatment: octreotide for symptomatic patients (somatostatin analog), surgery for liver metastases

FA332