hemostasis

Question 1

what cells produce von willebrand factor

Answer 1

endothelial cells when they are damaged it is exposed

Question 2

what binds the platelets to von willebrand

Answer 2

Gp1b very tight binding helps it withstand sheer force of the flowing blood.

Question 3

what else does von willebrand bind what clotting factor

Answer 3

Factor 8 this will improve the half life of the factor

Question 4

what on platelets binds collagen at the site of damage

Answer 4

a2b1 bind the platelet to the ecm

Question 5

what causes the shape change in the platelets

Answer 5

adhesion triggers release of Ca2+ that causes the shape change

Question 6

what does a dense granule from an activate platelet contain

Answer 6

ADP ATP Ca2+ histamine serotonin epinephrin

Question 7

what dose an alpha granule from an active platelet contain

Answer 7

fibrinogen fibronectin vWF coagulation factor 5 and PDGF

Question 8

what else does an activated platelet release

Answer 8

arachidonic acid that gets converted by COX to thromboxane A2

Question 9

what of the stuff that is released by platelets leads to vasoconstriction

Answer 9

thromboxane A2, serotonin epinephrin.

Question 10

what are signals for platelet aggregation

Answer 10

ADP and thromboxane A2

Question 11

what is a change triggered by ADP

Answer 11

conformation of Gp2b and Gp3a allows reception of fibrinogen

Question 12

what is the most common bleeding or clotting disorder

Answer 12

von Willebrand disease type 1 most common 80% are type 1

Question 13

tell me about Von willebrand disease

Answer 13

does not bind factor 8 so it will have a shorter half life treated with desmopressin

Question 14

what is bernard soulier syndrome

Answer 14

giant platelets often thrombocytopenia, fail to aggregate, defect in interaction of vWF and Gp1b so we give platelet transfusion when bleeding occurs or will occur

Question 15

what is glanzmann thrombasthenia

Answer 15

defective gP2b and/or gP3a , fail to aggregate therapy platelet transfusion to address bleeding

Question 16

what causes the intrinsic pathway to start

Answer 16

negative charged surface like glass. Leads to the test partial thromboplastin time test

Question 17

what causes the extrinsic pathway to start

Answer 17

tissue factor , leads to the test prothrombin time test

Question 18

name factors 1-4

Answer 18

fibrinogen, prothrombin, tissue factor, and Ca2+

Question 19

what factors contain carbocyglutamate and why

Answer 19

7 9 and 10. function to chelate ca2+ when bound to Ca2+ it makes the clot formation restricted to site of injury all require vit K

Question 20

what was the original developed for warfarin

Answer 20

rodenticide

Question 21

what is the most important pathway

Answer 21

extrinsic

Question 22

tell me about the steps to the extrinsic pathway

Answer 22

7 binds tissue factor, then binds 10, this will slowly activate thrombin from prothrombin and will activate factor5. Then 10a and 5a will complex with Ca2+ and this quickly activates prothrombin to thrombin.

Question 23

what is the key regulator of hemostasis

Answer 23

thrombin actiavtes fibrinogen, factors 5,7,and 8

Question 24

tell me about the intrinsic pathway

Answer 24

surface of endothelais cells, 11 and prekallikein in blood with kinogen will assemble, then carboxypeptidase clease prekallikrein,this will activate 12 which activaates 11 which activates 9 slowly, which actiaves thrombin which activates 8 and that rapidly acivates 10 .

Question 25

tell me about the common pathway

Answer 25

Factor 10 activates thombin activates 13 makes the clot hard by makding bonds between lysine and glutamine using transglutaminase

Question 26

what is hemophilia a and b

Answer 26

a most common deficiency in factor 8 B is a deficiency in factor 9, queen victoria had B

Question 27

what are some endogenous anti-coagulates activates

Answer 27

Thrombin , protein c and protein S , serpins and tissue factor pathway inhibitor

Question 28

tell me about thrombin protein c and s

Answer 28

thrombomodulin present in intact endothelial cell membrans when bound to thrombin will activae protien c and this will bind to protein s and form a complex that will degrade factor 8a and 5a

Question 29

what is factor V leiden

Answer 29

mutation in factor 5 ressistant oe cleavage by protein C causes hypercoagulation

Question 30

tell me about serpins

Answer 30

serine protease inhibitors binds heparin

Question 31

tell me about tissue factor pathway inhibitor or TFPI

Answer 31

made by endotheisial clls, inhibits factor 7a and blocks the extrinsic pathway also inhibits 10a

Question 32

tell me about fibrinolysis

Answer 32

plaminogen will bind fibrin activated by tPA this is released by activated protein c causes clot degradation

Question 33

what inhibits tPA

Answer 33

Alpha 2 antiplasmin and alpha2 macroglobulin

Question 34

what is streptokinase

Answer 34

produced b beta-hemolytic strptococci is an exogenous activator of plasminogen used to treat pulmonary embolism and DVT