Author Question: What are the primary roles of VWF? a. Mediates platelet adhesion and carrier molecule for factor ... (Read 55 times)

future617RT · **on:** Jun 25, 2018

What are the primary roles of VWF?

a. Mediates platelet adhesion and carrier molecule for factor VIII
b. Mediates platelet aggregation and carrier molecule for factor IX
c. Inhibits excess coagulation and activates protein C
d. Activates plasmin and enhances vitamin K factors

Question 2

Which patient group is most susceptible to bleeding because of a deficiency of vitamin Kdependent

a. Those with poor diets
b. Those on antibiotic agents
c. Pregnant women
d. Newborns

polinasid · **Reply #1 on:** Jun 25, 2018

Answer to Question 1

ANS: A
VWF is required for normal platelet adhesion; it is also the carrier protein for factor VIII, protecting it from proteolysis and thus prolonging the in vivo half-life from just a few minutes (in the absence of VWF) to 8 to 12 hours.

Answer to Question 2

ANS: D
Newborns are the most susceptible to vitamin K protein deficiency because the levels of the vitamin Kdependent proteins at birth are significantly lower than those for adults, and they drop even further the first few days of life. Breastfeeding prolongs the deficiency because passively acquired maternal antibodies delay establishment of the gut flora.