General Path Flashcards
What is aplasia vs hypoplasia?
Aplasia is a lack of cell production in embryogenesis. (absent organs)
Hypoplasia is decreased cell production in embryogenesis (smaller organs)
3 general causes of hypoxia
Ischemia
Hypoxemia
Decreased O2 carrying capacity
What is Methemoglobinemia?
When iron in the Hb is oxidized to Fe3+ which cannot bind oxygen
(treatment is methylene blue to get Iron back to Fe2+)
Hallmark of reversible cell injury
Cell Swelling
Hallmark of irreversible cell injury
Membrane Damage
How does irreversible cell injury result in apoptosis
Membrane damage occurs to the mitochondria in the cell which leads to leakage of Cytochrome c and activation of apoptotic enzymes
List the 3 nuclear changes that occur in cell death.
Pyknosis: condensation (shrinks)
Karyorrhexis: Fragmentation
Karylolysis: dissolution (fading)
Necrosis where the tissue is firm and architecture is maintained. Usually due to infarction, pale area.
Coagulative necrosis
Type of necrosis in brain infarction
Liquefactive
Coagulative necrosis that resembles mummified tissue.
Gangrenous Necrosis
Cottage-cheese like appearance necrosis
Caseous Necrosis
Combination of coagulative and liquifactive necrosis.
Caseous necrosis
Necrotic damage to blood vessel walls
Fibrinoid Necrosis
3 enzymes that reduce the amount of free radicals in the body.
Superoxide dismutase
Glutathione Peroxidase
Catalase
Mechanism of Reperfusion Injury.
Ishcemia to a region of tissue causes cell injury. Immediate return of blood to the area brings accumulated oxygen free radicals in high concentration which further damage the tissue.
Congo Red Staining with Apple Green birefringence.
Amyloidosis: misfolded proteins (from Ig light chains) that deposit in extracellular space
Most common organ involved in amyloidosis
Kidney: nephrotic syndrome
can also have restrictive cardiomyopathy, or tongue enlargement
Arachidonic acid metabolite that mediates pain.
PGE2
- produced from arachidonic acid by COX enzymes
- primary thing ASA tries to prevent from forming
Arachidonic Acid metabolite that is chemotactic
LTB4
-made from lipoxygenase enzymes
Major mediator from mast cells and what it does.
Histamine: increased vascular permeability, vasodilation of arterioles