UWorld_3.1

Question 1

Osteocytes connected to each other by:

Answer 1

gap jxns

Question 2

Tight jxn characteristics/locations

Answer 2

• “zona occludens”
• @ apex of glandular cells
• tight jxns = two closely adherent cytoplasmic membranes w/out intervening space
  
  • first component of a jxnl complex

Question 3

Desmosomes characteristics/locations

Answer 3

• desmosomes = small, circular, adherent patches
  
  • circumferentially placed around cells
  • comprise the thirds component of jxnl complex
• common @ stratified squamous epithelium
• contribute to structural cohesion of tissue subject to mechanical stressors

Question 4

Hemidesmosomes characteristics/locations

Answer 4

• = half desomosomes; extend from basal surfaces of keratinocytes @ stratified squamous epithelium to attach to basal lamina

Question 5

Intermediate jxns characteristics/locations

Answer 5

• “zona adherens”
• =delicate network of cytoplasmic filaments that radiate from the cell membrane to hold together adjacent cells
• second component of jxnl component

Question 6

Fxn of 99mmTc-pertechnetate scan

Answer 6

detects presence of gastric mucosa

Question 7

Characteristics/presentation of Meckel diverticulum

Answer 7

• failed obliteration of omphalomesenteric duct
  
  • e.g. accumulation of 99mmTc-pertechnetate @ right lower abdominal ==> indicates gastric mucosa
• ==> lower GI bleeding
• ==> right lower quadrant pain
• ==> intussusception ==> colicky abdominal pain + “currant jelly” stools

Question 8

Failure of ventral dorsal pancreatic bud fusion ==>

Answer 8

• formation of pancreas divisum
• usually asymptomatic

Question 9

Failure of hindgut descent along the inferior mesenteric artery ==>

Answer 9

• hindgut ==> distal third of transverse colon, descending, and sigmoid colon, rectum, upper part of anal canal
• failure of descent ==> various degrees of anal agenesis or imperforate anus

Question 10

Failure of midgut rotation around the superior mesenteric artery ==>

Answer 10

• ==> intestinal malrotation
• intestine is fixed by fibrous adhesive bands ==> intestinal obstruction

Question 11

Importance concept in studies looking at risk modigiers

Answer 11

• latent period
• exposure to risk modifiers may occur a significant amount of time before the exposure’s effect on the disease process
  
  • may have to be continued for years
• think about latency when looking at relative risk reductions between groups experiencing a risk modifier for different periods of time

Question 12

Trisomy 18 presentation

Answer 12

• 2nd most common autosmal trisomy
• face: eye defects, low-set ears, prominent occiput
• CNS: microcephaly, NTDs, Chiari malformation, developmental disability
• MSK: clecked hands + overlapping fingers, rocker-bottom feet, hypotonia
• Cardiac: VSD, PDA
• GI: Meckel’s, malrotation

Question 13

Deficiency of membrane attack complex ==>

Answer 13

• recurrent infections by Neisseria species
• N. meningitidis
  
  • high-fever, chills
  • AMS
  • petechial skin rash <== N.-induced small-vessel vasculitis
    
    • esp. @ palms, soles

Question 14

Factors that form the membrane attack complex + fxn

Answer 14

• C5b - C9
• forms pores @ bacterial cell membrane ==> electrolyte disturbances, inflow of free water, cell lysis

Question 15

Tx for N. meningitis

Answer 15

• IV ceftriaxone for 2 weeks

Question 16

Characteristics of Blastomycosis dermatitidis

Answer 16

• dimorphic fungus
  
  • mold form, found in soil, organic matter, and many animals
• ==> pulmonary infections (often chronic) in immunocompetent hosts
  
  • ​respiratory transmission
  • transforms to yeast @ lungs
  • granuloma formation
• Dx = sputum stain with KOH ==> round yeast w/thick, doubly refractive walls + single, broad-based buds
• endemic areas
  
  • Great Lakes, Mississippi & Ohio River Basin

Question 17

Tx of Blastomycosis dermatitidis

Answer 17

itraconazole

Question 18

Psych:

Reaction formation

Projection

Repression

Identification

Suppression

Displacement

Answer 18

• Rxn form = person does opposite (excessively) of what he/she desires; used to cover up feelings they believe to be unacceptable to society
• Projection = transplant unacceptable impulses to another person/situation
• Repression = unconscious removal of disturbing psych material from conscious awareness
• ID = modeling one’s behavior after someone perceived to be more powerful (e.g. abused child ==> abusing as a parent)
• Suppression = voluntary withholding of unpleasant htoughts or feelings from one’s mind
• Displacement = transfer of impulse or desire toward a safer and less distressful object

Question 19

Somatostatin from pancreas ==>

Answer 19

suppresion of secretin, cholecystokinin, glucagon, insulin, and gastrin

Question 20

Somatostatinomas ==>

Answer 20

• somatostatinoma = rare pancreatic cell tumors that arise from “delta cells”
• ==> hyper or hypoglycemia
• ==> steatorrhea
• ==> suppressed cholecystokinin ==> gallbladder stones

Question 21

Characteristics of acute compartment syndrome

Answer 21

• increased pressure w/in fascial compartment ==> compromised blood circulation and tissue fxn
• develops after significant trauma
  
  • e.g. long-bone fractures of leg or forearm

Question 22

Characteristics of Dupuytren’s Contracture

Answer 22

• benign, slowly progressive fibroproliferative disease of the palmar fascia
• scarring ==> nodules on palmar fascia ==> loss of finger flexibility ==> contractures that bring the fingers into flexion