Lesson 2

Question 1

Characteristics:

1. diameter
2. mpv
3. reference platelet count
4. daily turnover
5. lifespan
6. function: maintenance of _____ & ______
   - also in ______
   - esp platelet factor ____ which it’s important in activation of thromboplastin

Answer 1

1. 2-4um
2. 8-10fL
3. 150k - 450k /uL
4. 35x10^9 /L (+/-4.3)
5. 8-11 days
6. maintenance of vascular integrity & blood coagulation
   - clot formation
   - Platelet Factor 3/ Tissue Factor

Question 2

Substances: ALPHA GRANULES

________: role in Hemostasis
1. activation of intrinsic coagulation pathway
2. converted to fibrin for clot formation
3. cofactor in fibrin clot formation
4. assists platelet adhesion

Answer 2

Promote Coagulation
1. High Molecular Weight Kininogen
2. Fibrinogen
3. Factor V
4. Von Willebrand Factor

Question 3

Substances: ALPHA GRANULES

________: role in Hemostasis
1. promotes smooth muscle growth; wound healing
2. chemotactic for fibroblasts

other systems affected: role in Hemostasis
1. precursor to plasmin, which induces clot lysis
2. plasmin inhibitor, inhibits clot lysis
3. complement system inhibitor

Answer 3

Promote Vascular Repair
1. Platelet-derived growth factor
2. Beta-thromboglobulin

other systems affected: role in Hemostasis
1. Plasminogen
2. a2-antiplasmin
3. C1 esterase inhibitor

Question 4

ALPHA GRANULES
1. these two promote platelet aggregation

DENSE GRANULES
1. these two promote platelet aggregation
2. promotes vasoconstriction at injury site

MEMBRANE PHOSPHOLIPIDS
1. promote vasoconstriction at injury site

Answer 4

ALPHA GRANULES
1. Platelet Factor 4; Thrombospondin

DENSE GRANULES
1. ADP; Calcium
2. Serotonin

MEMBRANE PHOSPHOLIPIDS
1. Thromboaxane A2
precursors

Question 5

ADHESION DEFECTS

_____: characterized by large platelets & thrombocytopenia
1. deficiency in
2. prolonged bleeding time reference value
3. aggregate normally with
4. aggregate abnormally with

Answer 5

Bernard-Soulier Syndrome

1. Gp Ib/IX
2. 1-7mins
3. Epinephrine, ADP, Collagen
4. Ristocetin

Question 6

ADHESION DEFECTS:

_____: platelet count & morphology = generally NORMAL

1. autosomal deficiency in Factor ______
2. common sign
3. treatment with:
   - blood must be ____ to increase vWF
   - induces an effect on weibel-palade bodies

Answer 6

von Willebrand Disease

1. Factor VIII
2. mucocutaneous bleeding
3. treatment with:
   - cryoprecipitate
   - desmopressin acetate

Question 7

Classification of von Willebrand Disease:

1. partial quantitative deficiency of vWF
2. qualitative deficiency of vWF
3. decreased platelet-dependent vWF fxn w/ selective deficiency of
   high-molecular-weight multimers
   - enzyme that regulates blood clotting by breaking down the vWF
4. increased affinity for platelet glycoprotein Ib/IX/V
5. decreased platelet receptor binding
6. impaired factor VIII binding site
   - aka
7. vWF is absent or nearly absent from plasma

Answer 7

1. Type 1
2. Type 2
3. Type 2A
   - ADAMTS-13
4. Type 2B
5. Type 2M
6. Type 2N
   - Normandy variant
7. Type 3

Question 8

ADHESION DEFECTS

1. deficiency in Gp IIb-IIIa; inherited as autosomal recessive trait
   - aggregate normally in
   - aggregate abnormally in
2. absence of fibrinogen
3. decrease of fibrinogen

Answer 8

1. Glanzmann’s Thrombasthenia
   - ristocetin
   - ADP, Collagen, Epinephrine
2. Adibrinogenemia
3. Hypofibrinogenemia

Question 9

1. Adhesion defects: _______ interaction
2. Aggregation defects: _______ interaction

Answer 9

1. Platelet-Vessel Wall Interaction
2. Platelet-Platelet Interaction

Question 10

DISORDERS OF PLATELET SECRETION & SIGNAL TRANSDUCTION

Deficiency of Granules (_______):

1. characterized by larger platelets, colored gray to blue-gray, & thrombocytopenia
   - deficiency of ______
   - lab findings ______ & _____
2. w/ defect in cytoskeletal assembly; predominance of smaller platelets
   - deficiency of
   - remodeling actin myosin skeletal system
   - triad of symptoms

Answer 10

Storage Pool Disorders

1. Gray Platelet Syndrome
   - alpha granules
   - prolonged BT & decreased aggregation studies
2. Wiskott-Aldrich Syndrome
   - dense granules
   - WAS gene
   - thrombocytopenia, recurrent infection, & eczema

Question 11

DISORDERS OF PLATELET SECRETION & SIGNAL TRANSDUCTION

1. Hermansky-Pudlak Syndrome
   - deficiency of ______
   - triad of symptom
2. seen in wbcs
   - deficiency of
   - characterized by (3)

Answer 11

1. Hermansky-Pudlak Syndrome
   - dense granules
   - triad of symptom:
   *oculocutaneous albinism
   *bleeding tendencies
   *accumulation of ceroid-like pigment in macrophages
2. Chediak-Higashi
   - dense granules
   - albinism, recurrent infection, & giant lysosomes