Hematology 2 Lecture (Prelims)

• Introduction to Hemostasis is a course focusing on the three hemostatic components, the concepts of hypocoagulation and hypercoagulation, and the overview of the hemostatic mechanism.
• The extrinsic pathway of coagulation is activated when there is vascular endothelial injury which causes the exposure of the tissue factor (TF).
• The binding of tissue factor (TF) and plasma factor VII will lead to a series of enzymatic reactions that causes the activation of the common pathway.
• Fibrinolysis is the system whereby a temporary fibrin clot is systematically and gradually dissolved as the blood vessel heals.
• Fibrinolysis is a mechanism simultaneously activated with coagulation when there is vessel injury in order to restore normal blood flow.
• Damaged tissues release tissue plasminogen activator (tPA), which activates the inert substance, plasminogen to its active form, plasmin.
• The common pathway begins with the activation of factor X to its active form, either through the ex- or intrinsic pathway.
• The ultimate goal of common pathway activation is the formation and stabilization of a platelet-fibrin clot.
• Plasmin is capable of degrading the fibrin clot formed.
• Tissue factor (TF) is a receptor protein on cells that underlie the endothelium.
• The extrinsic pathway of coagulation is now thought to be the primary mechanism which coagulation is initiated.
• Prefixes in medical terms include a-/an-, aniso-, cyt-, dys-, erythro-, ferr-, hemo-, hypo-, hyper-, macro-, mega-, meta-, micro-, myel(o)-, pan-, phleb-, phago-, poikilo-, poly-, schis-, scler-, splen-, thromb(o)-, xanth-.
• Suffixes in medical terms include -cyte, -emia, -itis, -lysis, -oma, -opathy, -osis, -penia, -phil(ic), -plasia (plastic), -poiesis, -poietin.
• Derive a definition based on the prefix, root word, and suffix.
• Hematopoiesis refers to the production, formation, and development of blood.
• Macrocytosis is a condition in which there would be large cells.
• Aplasia is a condition of absence of cell production.
• Endothelial cells have antiplatelet activity.
• Hemolysis is the destruction of blood.
• The anti-thrombotic lining of BVs provides a smooth, non-reactive surface that facilitates blood flow and reduces turbulence which can promote thrombosis.
• In the undisturbed state of blood vessels (BVs), the BVs maintain blood in the liquid state because the intact endothelial lining of BVs is anti-thrombotic.
• Endothelial cells are capable of producing the enzyme, nitric oxide synthase, responsible for the production of NO, which comes from substrate L-arginine, and is responsible for vasodilation.
• The anti-thrombotic properties of BVs are due to the absence of turbulence, the tunic intima of BVs, which is comprised of the endothelial lining, individually comprised of endothelial cells that have (-) charge which will repel the plts.
• The anti-thrombotic lining of BVs does not activate platelets or promote coagulation.
• The substances listed in Table 8 are released from the endothelial cells and sub-endothelial smooth muscles contribute to normal blood flow and prevent abnormal formation of clots in BVs.
• Coagulopathy is a disease of clotting.
• Splenomegaly is a condition of having a large or giant spleen.
• Pancytopenia is a condition of decrease in all cell type.
• Agranulocytopenia is a condition of decrease in granulocytes.
• Intravascular refers to inside blood vessels.
• VWF assists platelet adhesion to the sub-endothelium to provide a coagulation surface.
• Fibrinogen is converted to fibrin for clot formation.
• Platelet Factor 4 promotes platelet aggregation and inhibits heparin.
• Calcium promotes platelet aggregation.
• Alpha-2 Antiplasmin is a plasmin inhibitor and inhibits clot lysis.
• Serotonin promotes vasoconstriction at the injury site.
• Factor V is a co-factor in fibrin clot formation.
• Plasminogen is a precursor to plasmin, which includes clot lysis.
• Neurosinin II inhibits Factor X Ia and thus factor IX activation.
• Platelet-derived Growth Factor promotes smooth muscle growth for vessel repair.