Lect Final 86%

Question 1

Infant Sample collection

Answer 1

• Must minimize the amount of sample drawn, due to small blood volume in infants

Question 2

“Well” infants experience

Answer 2

– Immune thrombocytopenia, vitamin K deficiency,
hemophilia, bleeding from a localized vascular lesion

Question 3

sick infants

Answer 3

– Prematurity, perinatal infection, respiratory distress
syndrome, metabolic derangements, birth asphyxia
▪ DIC, liver failure, isolated platelet consumption defect

Question 4

Identifying aPL Antibodies

Answer 4

1. Prolongation of a PL-dependent coagulation test (e.g.,
   APTT, dRVVT, KCT)
2. Evidence of inhibitor activity (lack of correction by a 1:1
   mix with normal plasma)
3. Confirmation that inhibitory effect blocks PL-dependent
   coagulation (i.e., neutralization of inhibitor effect by
   addition of excess PLs or changing PL source)
4. Absence of specific inhibitor against a coagulation factor

Question 5

Antiphospholipid Antibody Syndrome
(APLS

Answer 5

-Not clearly understood
-presents as VTE (DVT, PE), arterial thromboses (stroke, TIA, MI)
- recurrent miscarriages

Question 6

• Antiphospholipid antibodies

Answer 6

▪ Lupus anticoagulant (LA)
▪ Anticardiolipin antibodies (aCL)
▪ Several subgroups—antibodies to PLs and PL binding
proteins

Question 7

negatively charged surface

Answer 7

repels platelet and hemostatic proteins

Question 8

heparan sulfate(HS)

Answer 8

inhibits fibrin formation - cofactor for antithrombin

Question 9

thrombomodulin(TM)

Answer 9

binds thrombin and enhances activation of protein C

Question 10

endothelial protein C receptor

Answer 10

binds protein C and facilitates PC activation

Question 11

Tissue Factor pathway inhibitor TFPI

Answer 11

Binds TF/FVIIA/FXa complex
inhibits extrinsic pathway of coagulation

Question 12

Postacyclin PGI2

Answer 12

promotes vasodilation, inhibits platelet activation

Question 13

Tissue plasminogen activator tPA

Answer 13

activates fibrinolysis system

Question 14

Annexin A2 -tPa receptor A2

Answer 14

binds tPA and plasminogen, activates finbrinolysis

Question 15

Urinary type plasminogen activator

Answer 15

binds uPAR and plasminogen, activates fifrinolysis

Question 16

Nitric oxide NO

Answer 16

promotes vasodilation, inhibits platelet recruitment and accumulation

Question 17

ADPase CD39

Answer 17

degrades ATP and ADP to AMP anf adenosine

Question 18

Endothelin ET

Answer 18

promotes vasoconstriction

Question 19

vWF

Answer 19

carries FVIII in plasma, facilitates platelet adhesion

Question 20

tissue factor TF

Answer 20

initiates fibrin formation, activates FVII

Question 21

plasminogen activator inhibitor PAI-1

Answer 21

inhibits activation of fibrinolysis

Question 22

what activates fibrinolysis

Answer 22

tPA, A2, uPA, uPAR

Question 23

what is the difference btwn resting endothelium and activated

Answer 23

answer in book

Question 24

what are the 2 membrane systems

Answer 24

open canalicular
dense tubular

Question 25

open canalicular

Answer 25

originate from invagination of plasma membrane - provides route for substances entering and leaving platelet **- secretion of granule contents**

Question 26

dense tubular

Answer 26

originates from endoplasmic reticulum of MK **-storage site for Ca++** -major site for prostaglandin and TXA2

Question 27

what is in organelle zone

Answer 27

mitochondrion, a-granule, lysosome, dense granule, glycogen

Question 28

dense granules

Answer 28

non-protein mediators( ADP/ATP, Ca++, serotonin,

Question 29

α-granules (αG)

Answer 29

most numerous, Contain hemostatic/inhibitor/adhesive proteins **protein mediators**

Question 30

lysosomes

Answer 30

has hydrolytic enzymes and the release is associated with strong platelet agonists

Question 31

peroxisomes

Answer 31

fatty acid oxidation and synthesis of platelet activating factor (PAF) -lipid metabolism

Question 32

mitochondria

Answer 32

oxidative energy metabolism

Question 33

what does the pheripheral zone consist of

Answer 33

membrane and glycocalyx

Question 34

Glycocalyx (surface coat)

Answer 34

Responsible for negative charge of platelet surface Some proteins act as receptors for platelet activation

Question 35

plasma membrane

Answer 35

phosopholipid bilayer Asymmetric arrangement Contains integral proteins-->Receptors for VWF, fibrinogen, collagen, thrombin, fibronectin, and vitronectin

Question 36

structural zone

Answer 36

actin(g and f forms) microtubles submembranous cytoskeleton myosin

Question 37

reciporal protease

Answer 37

factor 12 and PK