M4 - XTRA PART III

Clot removal

protected by the clot, the endothelium and surrounding tunic are restored by new tissue, and the clot is then removed, mainly dissolved by the proteolytic enzyme plasmin, which is formed continuously through the local action of plasminogen activators from the endothelium on plasminogen from plasma.

Aspirin

an anti-inflammatory agent that contains an inhibitory effect on platelet function and blood coagulation because they block the local prostaglandin synthesis.

Bleeding disorders

it results from abnormally slow blood clotting.

Glycoprotein Ib deficiency

a disease directly related to a defect in the platelets that is a rare autosomal recessive, involving a factor on the platelet surface needed to bind subendothelial collagen.

Blood

a specialized connective tissue consisting of cells and fluid extracellular material called plasma.

Serum

a pale yellow liquid that contains growth factors and other proteins released from platelets during clot formation, which confer biological properties very different from those of plasma.

Hematocrit

erythrocytes that comprise the sedimented material, and their volume, normally about 44% of the total blood volume in healthy adults.

Buffy coat

a thin gray-white layer between the plasma and the hematocrit, about 1% of the volume, consists of leukocytes and platelets, both less dense than erythrocytes.

Plasma

an aqueous solution, pH 7.4, containing substances of low or high molecular weight that make up 7% of its volume.

Electrolytes

it includes nutrients, respiratory gases, nitrogenous waste products, hormones and inorganic ions.

Albumin

it is the most abundant plasma protein; it is made in the liver and serves primarily to maintain the osmotic pressure of the blood.

Globulins

known as a and b globulins; it is made by the liver and other cells, includes transferrin and other transport factors; fibronectin; prothrombin and other coagulation factors.

Immunoglobulins

known as antibodies or y-globulins; secreted by plasma cells in many locations.

Fibrinogen

the largest plasma protein; made in the liver which during clotting, polymerizes insoluble, cross-linked fibers of fibrin that block blood loss from small vessels.

Complement proteins

comprises a defensive system important in inflammation and destruction of microorganisms.

Water

92% of plasma; it is the solvent in which formed elements are suspended and proteins and solutes are dissolved.

Plasma proteins

7% of plasma; all proteins serve to buffer against pH changes.

Albumin plasma

58% of plasma proteins; exerts osmotic force to retain fluid within the microvasculature; contributes to blood’s viscosity; binds and transports some fatty acids, electrolytes, hormones and drugs.

a-Globulins; b-Globulins

transports lipids and some metal ions; transports iron ions and lipids in bloodstream.

y-Globulins

are antibodies with various immune functions.

Erythrocytes

are terminally differentiated structures lacking nuclei and completely filled with the O2-carrying protein hemoglobin.

Anemia

is the condition of having a concentration of erythrocytes below the normal range.

Sickle cell anemia

is caused by a homozygous mutation causing an amino acid substitution in hemoglobin, which renders the mature RBCs deformed and slightly rigid and can lead to capillary blockage.

Leukocytes

it leaves the blood and migrate to the tissue where they become functional and perform various activities related to immunity.

Granulocytes

possesses two major types of abundant cytoplasmic granules: lysosomes (often called azurophilic granules in blood cells) and specific granules that bind neutral, basic, or acidic stains.

Agranulocytes

it lacks specific granules but do contain some azurophilic granules.

Neutrophils

constitute about 50%-70% of circulating leukocytes, a figure that includes slightly immature forms released to the circulation.

Diapedesis

the process which the leukocytes send extensions through the openings between the endothelial cells, migrate out of the venules into the surrounding tissue space, and head directly for the site of injury or invasion.

Azurophilic primary granules

large, dense vesicles with a major role in both killing and degrading engulfed microorganisms.

Myeloperoxidase

generates hypochlorite and other agent toxic to bacteria.

Lysozyme

it degrades components of bacterial cell walls.

Defensins

small cysteine-rich proteins that bind and disrupt the cell membranes of many types of bacteria and other microorganisms.

Specific secondary granules

smaller and less dense, stain faintly pink, and have diverse functions, including secretion of various ECM-degrading enzymes.

Pus

a viscous, usually yellow collection of fluid from apoptotic neutrophils, bacteria, semi-digested material, and tissue fluid.

Eosinophils

far less numerous than neutrophils, constituting only 1%-4% of leukocytes; particularly abundant in connective tissue of intestinal lining and at sites of chronic inflammation.

Basophils

12-15 μm in diameter but make up less than 1% of circulating leukocytes and are therefore difficult to find in normal blood smears.

Leukotrienes

lipid-derived proinflammatory factors.

Lymphocytes

the most abundant type of agranulocytes in normal blood smears, it constitutes a family of leukocytes with spherical nuclei.

Lymphomas

are a group of disorders involving neoplastic proliferation of lymphocytes or the failure of these cells to undergo apoptosis.

Monocytes

precursor cells of macrophages, osteoclasts, microglia, and other cells of the mononuclear phagocyte system in connective tissue of nearly all organs.

Acute inflammation

usually short-lived as macrophages and undergo apoptosis or leave the site, but chronic inflammation usually involves the continued recruitment of monocytes.

Platelets

are very small nonnucleated, membranebound cell fragments only 2-4 μm in diameter.

Megakaryocytes

a giant polyploid bone marrow cells.

Alpha granules

are larger (300-500 nm in diameter) and contain platelet-derived growth factor (PDGF), platelet factor 4, and several other platelet-specific proteins.