PATHO HEHEHEHA Flashcards
Atrophy
-Decrease in cell size
-Decreases organ sizes if enough cells shrink
-Physiologic (function) Normal in early development
-Pathologic (disease) Results from decreases in workload, pressure use, blood supply, nutrition, hormonal/neural stimulation
Hypertrophy
-Increase in cell size
-Increases organ size
-Physiologic (function) Results from increased demand, stimulation by hormones, growth factors
-Pathologic (disease) Results from chronic hemodynamic overload.
Hyperplasia
-Increase number of cells
-Increased rate of cellular division
-Physiologic (function)
Compensatory- enables organs to regenerate.
Hormonal-In organs that respond to endocrine hormonal control
Pathologic (disease)
Hormonal- abnormal proliferation of normal cells.
Dysplasia
-Abnormal changes in size, shape, and organization of mature cells.
-May be reversible if the triggering stimulus is removed.
-tissue appears disorderly, but it is not cancer.
(If changes penetrate the basement membrane: invasive neoplasm)
Metaplasia
-Reversible replacement of one mature cell type by another
-Associated with tissue damage, repair, and regeneration
-Reprogramming of stem cells or undifferentiated mesenchymal cells
Necrosis
- Rapid loss of plasma membrane structure, organelle swelling, mitochondrial dysfunction, lacks typical features of apoptosis
-May be regulated or programmed
-Autolysis (autodigestion)
Coagulative necrosis
-Protein denaturation
-Albumin is transformed from a gelatinous, transparent state to a firm opaque substance
-Infarct (small localized area without blood supply)
Liquefactive necrosis
-Neurons and glial cells of the brain
-Cells are digested by their own hydrolases (an enzyme that breaks down chemical bonds)
-Tissues become soft and liquefied
-Triggered by bacterial infection
ex: Staphylococci, Streptococci, and Escherichia coli
Caseous Necrosis
-Results from pulmonary tuberculosis infection (bacterial infection of the lungs)
-Combination of coagulative and liquefactive necrosis
-
Fatty Necrosis
- Breast and other abdominal organs
-Action of lipases
-Fatty acids combine with elements to create soaps
-Tissue appears opaque and chalky white
Gangrenous Necrosis
-Death of tissue from severe hypoxic injury
-Dry (Skin becomes dry and shriveled, brown or black)
-Wet (Area becomes cold, swollen and black.) (Gas gangrene, caused by Clostridium)
Free Radicals
an electrically uncharged atom or
group of atoms with an unpaired electron that
damage:
* Lipid peroxidation
* Protein alteration
* DNA damage
* Mitochondrial effects
Ischemia
the decrease in blood supply to a tissue. It can be local, caused locally
by a thrombus or embolus, or global due to a low perfusion pressure.
Hypoxia (hypoxic injury)
The single most common cause of cellular injury
Results from:
* Ischemia—reduced supply of blood
* Reduced oxygen content in ambient air
* Loss of hemoglobin
* Decreased production of red blood cells
* Diseases of the respiratory and cardiovascular systems
* Poisoning of the oxidative enzymes (cytochromes) within
the cells
Anoxia—total lack of oxygen caused by
obstruction
Acute inflammation
Local manifestations
Result from cellular and vascular changes and
corresponding leakage of circulating components
into the tissue
Heat, swelling, redness, pain, loss of function
Exudative fluids
* Serous exudate (watery)
* Fibrinous exudate (thick and clotted)
* Purulent exudate (pus)
* Hemorrhagic exudate (erythrocytes)
4 phases of inflammation
- Vascular and Cellular
- VASODILATION (dilatation of blood vessels, which decreases blood pressure.)
- VASC PERMEABILITY: the blood vessels become more porous from
contraction of endothelial cells and leakage of fluid out of the vessel (exudate), causing swelling / edema at the site of injury, blood then starts to
move more slowly and collects at site of injury (ERYTHEMA) - WBC: sticks to inner walls of vessels and their migration through endothelial
cells
Thrombocytopenia
◦ Platelet count <150,000/mm3
◦ <50,000/mm3: hemorrhage from minor trauma
◦ <15,000/mm3: spontaneous bleeding
◦ <10,000/mm3: severe bleeding
*MAJOR causes = decreased platelet production, decreased platelet survival, splenic sequestration, and dilution