definitions

definitions until lecture 6

circulatory disturbances

disturbances of blood flow and body fluids

Edema

Abnormal increase of fluid in the interstitial tissue or body cavities

Hyperemia

Local increased blood volume in a vessel in a particular tissue

Active (arterial) hyperaemia

increased in the blood flow to an organ as a result of active dilatation of its arterioles and capillaries.

Passive (venous) hyperemia

increased venous blood in an organ as a result of obstruction of its venous outflow

Hemorrhage

the escape of blood outside the cardio-vascular system

external hemorrhage

escape of blood outside the body

internal hemorrhage

escape of blood in the body cavities

Hemothorax

accumulation of blood in pleural cavity

Hemopericardium

accumulation of blood in pericardial sac

Hemoperitonium

accumulation of blood in peritoneum

Hemoartherosis

accumulation of blood in joint cavity

Hematocele

accumulation of blood in tunica vaginalis

interstitial hemorrhage

escape of blood into the interstitial tissues

Hemostasis

Is a physiological process designed to stop bleeding from ruptured blood vessel

Thrombosis

Is a pathological process resulting in coagulation of blood inside intact blood vessel

Thrombosis

It is the process by which a solid mass called (thrombus) is formed from circulating blood elements mainly (platelets and fibrin) in the C.V.S. during life

Embolism

It is the circulation of an insoluble material in the blood and its sudden impaction in a narrow vessel

Pulmonary embolism

Emboli arise from recent thrombi of calf veins in the lower limbs

infraction

It is an area of ischemic necrosis due to occlusion of its arterial blood supply or rarely the venous drainage

Gangrene

Necrosis followed by putrefaction caused by bacterial activity saprophytic bacteria with the production of gases and toxins

Homeostasis

Normal cells have a fairly narrow range of functions or steady-state

Adaptation

excess physiologic or pathologic stress may force the cell to a new steady state that preserve the vitality of cells

Hypertrophy

increased organ size due to increase the size of its component cells – It is associated with increased RNA activity

Atrophy

decreased organ size due to decreased the number and/or the size of its component cells

Hyperplasia

increased organ size due to increase the number of its component cells – It is associated with increased DNA activity (required for cell division).

Metaplasia

it is a reversible replacement of mature tissue by another mature tissue of the same category

Cell injury

It is a change in the cell morphology and function in response to stress (irritant).

• This occurs when the cells can not able to adapt

Cloudy swelling

reversible cell injury in which the cells becomes swollen with granular cytoplasm due to intracellular accumulation of water

Fatty change (steatosis)

reversible cell injury characterized by abnormal intracytoplasmic accumulation of neutral fat (triglycerides) in the cytoplasm of parenchymatous organs

Pathological calcification

it is an abnormal deposition of calcium salts (calcium phosphate & carbonate) in tissues other than bone and teeth.

• Ca+ usually deposits in the alkaline pH

Dystrophic calcification

It is an abnormal deposition of calcium salts in degenerated and necrotic tissues with normal blood calcium level

• It is the most common form of pathological calcification

Metastatic calcification

It is abnormal deposition of calcium salts in normal tissue in cases of hypercalcemia (elevated blood calcium level)

Necrosis

Death of a group of cells or tissue within a living body. It is due to severe injury for long time

Coagulative necrosis

• The commonest type.

• Denaturation of protein predominates with the preservation of cell outlines without cellular details.

• Caused by acute ischemia as infarction of all organs except the brain.

Liquefactive necrosis

• Enzymatic digestion predominates Thus the necrotic tissue is liquefied by enzymes

• the cell outlines and cellular details are lost

Caseation necrosis

It is a type of coagulative necrosis in which the necrotic area appears like cheese (firm, yellow & friable)

Fat necrosis

Trauma or enzymes leads to rupture of fat cells, release of lipase that digest fat cells and initiate chronic inflammatory changes

Fibrinoid degeneration

Presence of brightly eosinophilic material (PAS positive)

Apoptosis

Programmed single-cell death, based on activation of suicide pathway genes (cell suicide) that control cytoplasmic enzymes

Bacterial Infection

invasion of the body by pathogenic Bacteria

Bacteremia

transient presence of small number of low virulent bacteria in the blood without toxins

Toxemia

circulation of bacterial toxins in blood with clinical and pathological manifestations

Septicemia

the circulation & multiplication of large number of virulent micro-organism & their toxins in the blood (highly fatal)

Pyaemia

circulation of septic emboli in the blood and their arrest in different organs causing multiple small abscesses. The condition is highly fatal