UWorld

Question 1

What 2 cell types are responsible for the proliferation of an atherosclerotic plaque?

Answer 1

Platelets and macrophages

Question 2

What is the most common genetic combination for a complete molar pregnancy?

Answer 2

Empty egg + 1 sperm, then 1 sperm duplicates

90% 46, XX

Question 3

By what mechanism does mutated huntingtin protein cause transcriptional repression?

Answer 3

Histone deacetylation

Question 4

How is the uterine fundus normally formed embryologically?

Answer 4

Lateral fusion of paramesonephrine ducts

Question 5

How do you differentiate between a septate and bicornuate uterus?

Answer 5

On MRI, septate has normal uterine contour whereas bicornuate does not.

Question 6

What does the presence of HBsAg mean?

Answer 6

Active infection - acute or chronic

Question 7

What does the presence of HbeAg mean?

Answer 7

High infectivity

Question 8

What key intermediate regulates the balance between fatty acid synthesis and degradation?

Answer 8

Malonyl-CoA

Question 9

What determines coronary dominance?

Answer 9

The coronary that supplies the PDA (which supplies the AV node) determines dominance, mostly right-dominant

Question 10

In areas with chloroquine-resistant malaria, what are the treatments of choice?

Answer 10

Mefloquine or atovaquone + proguanil

Question 11

What part of the brain is injured in hemiballimus?

Answer 11

Subthalamic nucleus

Question 12

What is underlying etiology in a patient with blue-black spots on sclerae, connective tissue hyperpigmentation, and severe arthritis?

Answer 12

Alkaptonuria

Question 13

What factors precipitate sickling in sickle cell anemia?

Answer 13

Low O2, high altitude, acidosis (deoxygenated)

Question 14

What do RBCs rely on for ATP production?

Answer 14

Lactic acid fermentation

Question 15

What is most of the ATP in RBCs used for?

Answer 15

Membrane maintenance and structural integrity

Question 16

What is associated with caudal regression syndrome?

Answer 16

Maternal diabetes

Question 17

What can cause paresthesias following massive blood transfusion?

Answer 17

Hypocalcemia (from citrate mixed into blood before storage)

Question 18

What arteries supply the lesser curvature of the stomach?

Answer 18

Gastric arteries

Question 19

What are the 3 most common cancers in women (other than skin cancers)?

Answer 19

Breast, lung, colon

Question 20

What microbial component has the closest correlation with disease severity in meningococcus meningitis?

Answer 20

LOS protein

Question 21

Biopsy of sinus mucosa reveals wide angle, non-septate hyphae in an immunocompromised individual. What is the organism?

Answer 21

Mucor or Rhizopus

Question 22

Bartonella henselae is responsible for which 2 diseases?

Answer 22

Cat scratch disease and bacillary angiomatosis

Question 23

Dx for young, obese woman with transient vision loss worsened with bending forward or lifting things and a persistent headache?

Answer 23

Pseudotumor cerebri

Question 24

What is the etiology of S4?

Answer 24

HOCM

Question 25

What is the only antibody that crosses the placenta?

Answer 25

IgG

Question 26

What biochemical marker is elevated in hydatidiform moles and what malignancy is it correlated with?

Answer 26

b-HCG, choriocarcinoma

Question 27

What is the difference between somatic and gonadal mosaicism?

Answer 27

Somatic mosaicism cannot be passed on, gonadal mosaicism has family history and can be passed on

Question 28

What is the treatment of choice for patients with acute MI and history of lung disease?

Answer 28

B1-specific blocker ??

Question 29

What nerve can be damaged by lateral fibular damage?

Answer 29

Common peroneal nerve

Question 30

How do osteocytes communicate with each other?

Answer 30

Through processes in canaliculi, via gap junctions

Question 31

What is the pathophysiology of HSP?

Answer 31

IgA immune complex-mediated vasculitis (type III hypersensitivity)

Question 32

What causes apple-peel deformity?

Answer 32

Vascular occlusion/ischemia

Question 33

What enzyme is responsible for changing bilirubin to biliverdin?

Answer 33

Heme oxygenase

Question 34

What organism is stained red by mucicarmine?

Answer 34

Cryptococcus neoformans

Question 35

Nitrites are given to treat toxicity from what compound?

Answer 35

Cyanide - increases hemoglobin affinity for cyanide to keep it bound so it can't be toxic

Question 36

What brain mass gives rise to papilledema and Parinaud syndrome?

Answer 36

Pinealoma - papilledema from obstructive hydrocephalus, Parinaud from compression of the tectum

Question 37

What is Parinaud syndrome?

Answer 37

Compression of the tectum resulting in limited upward gaze, upper eyelid proptosis, pseudo-Argylle-Robertson pupils

Question 38

What vein drains the head, neck, and upper extremity?

Answer 38

Brachiocephalic vein (IJ + EJ + SC)

Question 39

How does potassium iodide prevent thyroid damage after exposure to iodine-131?

Answer 39

Competes with I-131 for uptake into thyroid so the more benign iodine there is, the less radioactive I-131 the thyroid takes in

Question 40

Dx for patient with diplopia that worsens throughout the day?

Answer 40

Myasthenia gravis

Question 41

In a patient with myasthenia gravis, what are the 2 causes for an acute crises?

Answer 41

Myasthenic crisis - undertreated, will improve with edrophonium Cholinergic crisis - overtreated, will not improve with edrophonium

Question 42

Dx for patient with hx of asthma and recurrent, migratory lung infiltrates?

Answer 42

Aspergillosis - ABPA

Question 43

What is the MOA of pioglitazone?

Answer 43

Binds PPARy (intracellular) --> alters transcription --> change lipid and glucose metabolism

Question 44

What is the difference between 21-hydroxylase deficiency and 11b-hydroxylase deficiency?

Answer 44

No mineralocorticoid in 21-deficiency --> hypotension and increased renin Increased weak mineralocorticoid in 11-deficiency (11-DOC) --> hypertension and decreased renin

Question 45

What is compliance?

Answer 45

change in volume/change in pressure

Question 46

What movement is the supraspinatus responsible for?

Answer 46

Arm abduction

Question 47

What is the effect of nitrites on hemoglobin?

Answer 47

Induces methemoglobinemia

Question 48

What is the difference in the role of Ca2+ influx during contract between skeletal muscle and cardiac/smooth muscle?

Answer 48

Skeletal - mechanical coupling between L-type Ca2+ channels and RyR on SR (verapamil-resistance) Cardiac/smooth - Ca2+-dependent Ca2+ release from SR (verapamil works)

Question 49

1 week after an ischemic brain injury, what do you expect to see histologically?

Answer 49

Microglia have phagocytosed myelin from dead nuclei, will stain red with lipid stain

Question 50

Dx of pt with expressive aphasia and hemiplegia, CT hypodensity in brain 1 week after?

Answer 50

Stroke/ischemic disease of brain

Question 51

What are the two exceptions the general scheme of the sympathetic nervous system?

Answer 51

General scheme: ACh from short preganglionic - nAChR, adrenergic from long postganglionic to target Exceptions: 1) adrenal medulla - AChR, direct release of NE/epi into blood 2) eccrine sweat glands - AChR, then ACh to mAChR on sweat glands

Question 52

In areas with chloroquine-resistant malaria, what are the treatments of choice?

Answer 52

Mefloquine or atovaquone+proguanil

Question 53

What are the risk factors for black gallstones?

Answer 53

Chronic hemolysis, increased enterohepatic cycling of bilirubin

Question 54

What are the risk factors for brown and cholesterol gallstones?

Answer 54

Biliary tract infection - releases microbial b-glucuronidases

Question 55

What does homogentisic acid dioxygenase deficiency cause?

Answer 55

Alkaptonuria

Question 56

What effects do alpha-1 agonists have on PVR, blood pressure, pulse pressure, and heart rate?

Answer 56

Increases PVR Increases blood pressure Decreases pulse pressure Decreases heart rate (vagal reflex to vasoconstriction)

Question 57

What part of the spleen is involved in removing damaged RBCs?

Answer 57

Red pulp

Question 58

What causes urge incontinence?

Answer 58

Uninhibited bladder contractions (detrusor instability)

Question 59

Where is PAH concentration the lowest in the kidney?

Answer 59

Bowman's space

Question 60

What’s the difference between 21-hydroxylase and 11-hydroxylase deficiency?

Answer 60

21-hydroxylase: no mineralocorticoid produced = hypotension, decreased Na+, increased K+ 11-hydroxylase: weak mineralocorticoid produced = hypertension, increased Na+, decreased K+

Question 61

Dx for patient with pruritis after showering?

Answer 61

Polycythemia vera

Question 62

What is the treatment of choice for patients with acute MI and history of lung disease?

Answer 62

A-M beta blockers (metoprolol)

Question 63

What are the 3 biggest risk factors for coronary heart disease?

Answer 63

Atherosclerosis, diabetes mellitus, CKD

Question 64

Which are the only 2 insulins that are human recombinant without any amino acid modifications?

Answer 64

Regular insulin and NPH