Lecture - Module 2

Question 1

occurs within the intravascular

compartment lined with endothelium

Answer 1

HEMOSTASIS

Question 2

A tightly regulated balance between formation and dissolution of hemostatic plugs modulated by a series of enzymes and scaffolding proteins.

Answer 2

PHYSIOLOGIC HEMOSTATIC SYSTEM

Question 3

Factors involved in Normal

Hemostasis and Thrombosis

Answer 3

Plateletes, Granulocytes & Monocytes

Coagulation Protein Sytem (Clot Forming)

Fibrinolysis Protein System (Clot Lysing)

Anticoagulation Protein System ( Regulating)

Question 4

serves to form thrombin that initiates the proteolysis of fibrinogen, leading to fibrin clot formation

Answer 4

Coagulation System (Clot Forming)

Question 5

→ functions to lyse the clot formed by thrombin

Answer 5

Fibrinolytic Sytem (Clot Lysing)

Question 6

regulates all enzymes of the coagulation and fibrinolytic systems, so that no inappropriate excess of clotting or bleeding occurs.

Answer 6

Anticoagulation System (Regulating)

Question 7

Vasoconstriction is a short-lived reflex reaction of the smooth muscle in the vessel wall produced by the

Answer 7

sympathetic branches of the autonomic nervous system

Question 8

increases the adhesiveness of platelets

Answer 8

ADP

Question 9

Platelet during adhesion will transform from ________ to ______ which produces surface membrane organization

Answer 9

disc shape to a sphere with pseudopods

Question 10

Internal contraction of the platelet results in release of granular contents of

Answer 10

alpha granules
dense granules
lysosomal granules

Question 11

Platelets adhere at sites of mechanical vascular injury and then undergo activation and express what functional glycoprotein —- also referred to as?

Answer 11

IIb/IIIa

Alpha 2b Beta 3

Question 12

Which receptors will mediate the recruitment of local platelets by forming fibrinogen bridges between platelets—a process called platelet cohesion.

Answer 12

glycoprotein IIb/IIIa

Question 13

A process forming fibrinogen bridges between platelets

Answer 13

platelet cohesion

Question 14

Glycoprotein ____ is specific for

platelets.

Answer 14

IIb/IIIa

Question 15

Glycoprotein ______ is the most abundant platelet membrane protein (with approximately _______ receptors per platelet).

Answer 15

IIb/IIIa

50,000

Question 16

gold standard test to determine platelet function.

Answer 16

Platelet aggregation

Question 17

Agents capable of producing platelet aggregation in vitro (an energy dependent process):

Answer 17

Collagen

Proteolytic enzymes (thrombin)

Biological amines (epinephrine and serotonin)

Question 18

results from bridges formed by fibrinogen in the presence of calcium which produces sticky surface on platelets

Answer 18

Aggregation

Question 19

If these aggregates are reinforced by fibrin, they are referred to as a

Answer 19

thrombus

Question 20

Aggregation of platelets by at least one pathway can be blocked by substances such as:

Answer 20

PGE (prostaglandin E)

adenosine

Question 21

• provides basis for platelet consolidation & stabilization.

Answer 21

Fibrinogen

Question 22

This process involves the precipitation of polymerized fibrin around each platelet

Answer 22

PLATELET PLUG CONSOLIDATION & STABILIZATION

Question 23

Result of platelet plug consolidation and stabilization

Answer 23

fibrin clot

Question 24

Fibrin clot will produce

Answer 24

irreversible platelet plug

Question 25

Quantitative Determination of Platelet

Answer 25

Electronic particle counter | examination of stained blood film

Question 26

done if the platelet count is normal → assessment of platelet function

Answer 26

Qualitative Assessment of Platelet

Question 27

Qualitative Assessment of Platelet

Answer 27

a. PBS b. Platelet Count c. Template Bleeding Time d. Petechiometer e. Platelet Aggregation f. Platelet lumiaggregation (release) g. Platelet Antibodies (IgM and IgG) h. Platelet Membrane Glycoproteins i. Platelet factor IV k. Thromboxanes

Question 28

In vivo measurement of platelet adhesion and aggregation on locally injured vascular subendothelium.

Answer 28

Bleeding Time with and without Aspirin

Question 29

Provides an estimate of the integrity of the platelet plug and thereby measures the interaction between the capillaries and platelets

Answer 29

Bleeding Time with and without Aspirin

Question 30

Reflects the number and quality of platelets, fibrinogen concentration, fibrinolytic activity, and packed red cell volume.

Answer 30

Clot Retraction

Question 31

The degree of clot retraction is __________ to the number of | platelets & __________ to the hematocrit and the level of the blood coagulation factor fibrinogen.

Answer 31

directly proportional | inversely proportional

Question 32

The principle of the test is that platelet-rich plasma is treated with a known aggregating agent. If aggregated, cloudiness or turbidity can be measured using a spectrophotometer.

Answer 32

Platelet Aggregation

Question 33

Aggregating agents

Answer 33

``` ADP Collagen Epinephrine Ristocetin Snake venom Thrombin ```

Question 34

Available techniques can include complement fixation methods, lysis of chromium 51 labeled platelets, assays of platelet-bound immunoglobulins, and competitive inhibition assays.

Answer 34

Antiplatelet Antibody Assays

Question 35

VASCULAR DISORDERS

Answer 35

1. Purpura associated with direct endothelial cell damage. 2. Purpura associated with an inherited disease of the connective tissue. 3. Purpura associated with decreased mechanical strength of the microcirculation. 4. Purpura associated with mechanical disruption of small venules. 5. Purpura associated with microthrombi (small clots). 6. Purpura associated with vascular malignancy.

Question 36

Demonstrates the smallest platelets seen

Answer 36

Wiskott-Aldrich | syndrome

Question 37

Characterized by the presence of large platelets and the presence of Döhle-like bodies in the granulocytic leukocytes

Answer 37

May-Hegglin | anomaly

Question 38

Disorder that exhibits giant platelets and thrombocytopenia

Answer 38

Alport syndrome

Question 39

Demonstrates the largest platelets. In this disorder, it has been demonstrated that the giant platelets are probably an artifact of the slide

Answer 39

Bernard-Soulier syndrome (giant platelet syndrome)

Question 40

3 types of thrombocytopenia

Answer 40

Disorder of production disorder of destruction or utilization disorder of platelet distribution

Question 41

Hereditary or familial thrombocytosis associated with ger_x0002_mline mutations of the thrombopoietin (THPO) gene in the THPO receptor (MPL) gene

Answer 41

THROMBOCYTOSIS

Question 42

associated with myeloproliferative neoplasms and/or myelodysplastic disorders (clonal thrombocytosis associated with somatic mutations of JAK2[V617F], MPL, and additional currently unknown genes)

Answer 42

THROMBOCYTOSIS

Question 43

reactive disease

Answer 43

secondary thrombocytosis

Question 44

TYPES OF PLATELET DYSFUNCTION

Answer 44

a) Acquired b) Drug-Induced c) Platelet Membrane Receptors d) Hereditary

Question 45

Types of acquired platelet dysfunction

Answer 45

``` Myeloproliferative Uremia Miscellaneous Paraprotein Cardiopulmonary bypass and platelet function ```

Question 46

Types of hereditary platelet dysfunction

Answer 46

i. Bernard-Soulier Syndrome ii. Glanzmann Thrombasthenia and Essential Athrombia iii. Hereditary Storage Pool Defect