cellular responses to stress and toxic insult 3 Flashcards
what are some reversible ischemia effects?
ATP depletion formation of blebs swollen mitochondria dilated ER swollen cell
what are some irreversible ischemia effects?
severe swelling of mitochondria
swelling of lysosomes
large amorphous densities develop i the mitochodrial matrix
how long of ischemia will result in irreversible injury?
30-40min
how do you treat ischemic brain and spine?
transient induction of hypothermia
this suppresses formation of free radicals
what is ischemia-reperfusion injury?
damage after reperfusion of ischemia. reoxygenation can damage cells by -increased generation of reactive nitrogen and oxygen species and free radicals -calcium can also enter cells -cytokines can cause inflammation -activation of complement system
what is direct chemical toxic injury?
combining with critical molecular components.
ex: mercury binds o sulfydryl groups in membrane proteins.
what is the most characteristic feature of apoptosis?
condensing chromatin
cell also shrinks
which caspases initiate apoptosis?
caspases 8 and 9
exists as proenzymes or zymogens
undergo enzymatic cleavage to become active
which caspases are executioners of apoptosis?
caspases 3 ad 6
exists as proenzymes or zymogens
undergo enzymatic cleavage to become active
what is a xanthoma?
Intracellular accumulation of cholesterol within macrophages (acquired and hereditary hyperlipidemic states)
Clusters of foamy cells are found in the subepithelial connective tissue of the skin and in tendons
what is cholesterolosis
Focal accumulations of cholesterol-laden macrophages in the lamina propria of the gallbladder
what is niemann pick disease type C?
- Lysosomal storage disease
- Caused by mutations affecting an enzyme involved in cholesterol trafficking
- Cholesterol accumulation in multiple organs
what kind of disease do you see from alpha 1 antitrypsin deficiency?
emphysema
Eosinophilic cytoplasmic inclusion in liver cells
Composed predominantly of keratin intermediate filaments
alcoholic hyaline
Insoluble pigment
Also known as lipochrome or wear-and-tear pigment
Not injurious to the cell or its functions
Telltale sign of free radical injury and lipid peroxidation
Yellow-brown, finely granular cytoplasmic, often perinuclear, pigment in tissue sections
Seen in cells undergoing slow, regressive changes
Prominent in the liver and heart
Aging patients
Patients with severe malnutrition and/or cancer cachexia
lipofuschin
Endogenous
Non-hemoglobin-derived brown-black pigment
Formation
Enzyme tyrosinase catalyzes the oxidation of tyrosine to dihydroxyphenylalanine in melanocytes
The only endogenous brown-black pigment
melanin
Hemoglobin-derived
Golden yellow-to-brown, granular or crystalline pigment
Serves as one of the major storage forms of iron
Represents aggregates of ferritin micelles
Seen normally in mononuclear phagocytes of the bone marrow, spleen, and liver
Actively engaged in red cell breakdown
hemosiderin
Normal major pigment found in bile
Derived from hemoglobin
Contains no iron
bilirubin
what is dystrophic calcification vs metastatic calcification?
dystrophic calcification - normal levels of serum calcium in necrotic tissue
metastatic calcification - high levels of calcium in normal tissue. Not necrosis
