6/1 Mixed

Question 1

The omphalomesenteric (vitelline) duct

Answer 1

Normally obliterates during the 7th week of embryonic development
Both enterocysts and Meckel diverticula result from a failure of obliteration involving the omphalomesenteric duct
“The cyst is connected by a fibrous band to the ileum and the umbilicus”

Question 2

Pulmonary emboli

Answer 2

Typically appear as multiple wedge-shaped hemorrhagic lesions in the periphery of the lung
IV drug users are at risk for developing septic pulmonary emboli as a complication of tricuspid valve endocarditis

Question 3

Opsonization

Answer 3

Occurs when host proteins such as immunoglobulins or complement bind to foreign cells such as bacteria and coat the surface, enhancing phagocytosis
The most important opsonins (coating proteins) and immunoglobulin G and complement C3b

Question 4

Ovarian torsion

Answer 4

Typically involves twisting of the INFUNDIBULOPELVIC LIGAMENT, often due to the weight of a large adnexal mass
The resulting occlusion of the blood and nerve supply to the ovary results in severe, acute pelvic pain and ovarian ischemia

Question 5

Common peroneal nerve injury

Answer 5

Vulnerable to injury where it courses around the neck of the fibula
Fibular neck fractures can injure this nerve, causing weakness of dorsiflexion (deep peroneal nerve) and eversion (superficial personal nerve) of the foot as well as loss of sensation over the dorsum of the foot

Question 6

Hypersecreting adrencortical tumors

Answer 6

Can have functionality resembling the outer (aldosterone/Conn syndrome), middle (cortisol/Cushing syndrome), or inner (adrogens/hirsutism and virilization) layers of the adrenal cortex
Hyperaldosteronsim: hypertension, hypokalemia, metabolic alkalosis (paresthesias and muscle weakness)

Question 7

Ovary cell type

Answer 7

Ovary is covered by simple CUBOIDAL epithelium

Question 8

Complete mole

Answer 8

Usually results when an empty ovum is fertilized by a haploid sperm
Subsequent duplication of the paternal genetic complement (23X) results in the characteristic 46, XX genotype

Question 9

Hematogenous osteomyelitis

Answer 9

MC in children, usually affects the METAPHYSIS OF LONG BONES due to the slower blood flow and capillary fenestrae in this region; without proper treatment, the infection can progress to chronic suppurative osteomyelitis

Question 10

Transfer RNA (tRNA)

Answer 10

Small, noncoding form of RNA that contains chemically modified bases (dihydrouridine, ribothymidine, pseudouridine). tRNA has a CCA sequence at its 3’ end that is used as a recognition sequence by proteins
The 3’ terminal hydroxyl group of the CCA tail serves as the amino acid binding site

Question 11

Isotretinoin

Answer 11

Used to treat severe acne with significant scarring
Pregnancy is an absolute contraindication due to the risk of teratogenicity
Sexually active women should be advised to use 2 forms of contraception and take monthly pregnancy tests

Question 12

Aspirin intoxication

Answer 12

Should be suspected in a patient with the triad of fever, tinnitus, and tachypnea
Adults with ASA toxicity usually present with a mixed respiratory alkalosis and anion gap metabolic acidosis
When the PaCO2 and HCO3 are outside the normal range, a normal pH suggests a mixed acidosis/alkalosis disorder, as compensatory responses do not correct the pH completely

Question 13

Echinococcus granulosus

Answer 13

Most common cause of hydatid cysts
Spilling of cyst contents can cause anaphylactic shock
Surgical manipulation should be performed with caution

Question 14

Fibroadenomas

Answer 14

Most common benign tumor of the breast
Characterized histologically by a cellular or myxoid stroma that encircles and sometimes compresses epithelium-lined glandular and cystic spaces

Question 15

Congential toxoplasmosis

Answer 15

TORCH infection (acquired in utero)
Its classic triad includes hydrocephalus, intracranial calcifications and chorioretinitis
Expecting mothers should avoid cat feces to help prevent exposure

Question 16

Homocystinuria

Answer 16

Most commonly caused by cystathionine synthase deficiency
Affected individuals have marfanoid habitus, ectopia lentis, developmental delay
Significant morbidity and mortality due to thromboembolism
Many patients with homocystinuria respond dramatically to pyridoxine (vit B6) supplementation

Question 17

Lymph from the testes

Answer 17

Drains through lymph channels directly back to the para-aortic lymph nodes
In contrasts, lymph from the scrotum drains to the superficial inguinal lymph nodes

Question 18

Seronegative spondyloarthropathies

Answer 18

Ankylosing spondylitis, reactive arthritis, psoriatic arthritis, arthritis associated with IBD
Individuals expressing HLA B27 are at increased risk for seronegative spondyloarthropathies

Question 19

Borderline personality disorder

Answer 19

Persistent pattern of unstable relationships, mood lability, and impulsivity
May exhibit suicidal ideation or behavior in the context of interpersonal crisis in which they feel rejected or abandoned

Question 20

Brown adipose tissue

Answer 20

Found in newborns and hibernating mammals
Brown adipose cells contain several intracytoplasmic fat droplets and many more mitochondria than white adipose cells
They function to produce heat by uncoupling oxidative phosphorylation with the protein thermogenin

Question 21

Risk of wrong-site surgery can be reduced by requiring

Answer 21

“dual identifiers” (usually a nurse and physician) to independently confirm that they have the correct patient, site, and procedure
Checks must be truly independent to ensure patient safety

Question 22

Treatment of psoriasis

Answer 22

Ranges from topical therapies to systemic treatment with conventional and biologic drugs
Topical vitamin D analogs (calcipotriene, calcitriol, tacalcitol) bind to the vitamin D receptor and inhibit keratinocyte proliferation and stimulate keratinocyte differentiation

Question 23

Dopamine agonists

Answer 23

Chemical structure similar to the NT dopamine and directly stimulate dopamine receptors
2 classes of dopamine agonists are ergot compounds (bromocriptine) and nonergot compounds (pramipexole, ropinirole)

Question 24

Parkinson disease Rx

Answer 24

Typically treated with levodopa (immediate precursor of dopamine) which cross the BBB. Levodopa is administered with DOPA decarboxylase inhibitors (carbidopa) and sometimes COMT inhibitors (entacapone) to reduce the peripheral metabolism of levodopa, resulting in increased levodopa bioavailability to the brain

Question 25

Fibrates

Answer 25

Lower TG levels by activating peroxisome proliferator-activated receptor alpha (PPAR-a) which leads to decreased hepatic VLDL production and increased lipoprotein lipase activity

Question 26

Common peroneal nerve damage

Answer 26

Trauma or sustained pressure to the NECK OF THE FIBULA can cause injury to the common peroneal nerve as it courses superificially and laterally to this structure
Affected patients have weakness in foot dorsiflexion and eversion and impaired sensation over the dorsal foot and lateral shin