clotting cascade

Question 1

thrombin is need for what?

Answer 1

fibrinogen–> fibrin
XIII–> XIIIa
V–>Va
VIII–>VIIIa

activating platelets

Question 2

how does warfarin exert its affects

Answer 2

inhibits action of vitamin K by targeting the epoxide reductase enzyme

this enzyme reduces Vit. k after its been oxidized in the carboxylation of glutamic acid

Question 3

what is the active form of Vitamin K

Answer 3

quinol

Question 4

what is Vitamin K a cofactor for?

Answer 4

factors: 2, 7, 9, 10, Protein C, and protein s

important in the gamma-glutamyl carboxylation

Question 5

what does protein C and S do

Answer 5

inactivate 5a and 8a

Question 6

what defects lead to increased risk of clotting/thrombosis

Answer 6

defect in protein c, protein s, VLeiden

Question 7

what is hemophilia A

Answer 7

factor VIII deficiency

Question 8

what is hemophilia B

Answer 8

factor 9 deficiency

Question 9

what is heparin and what does it inhibit

Answer 9

anti-coagulant

inhibits factors 2a, 9, 10a

Question 10

what does Vitamin K do?

Answer 10

Introduces Ca2+ binding sites via γ-carboxylation of glutamic acid residues in these factors (2, 7, 9, 10)

Question 11

what does PT measure

Answer 11

extrinsic pathway

Question 12

what does PTT measure

Answer 12

intrinsic pathway

Question 13

what will show a prolonged PT and normal PTT

Answer 13

liver disease, decrease vitamin K, DIC

Question 14

what factors are part of the intrinsic pathway

Answer 14

8, 9, 11, 12