Cell Injury and Adaptation Flashcards
Permenant tissue
Cardiac muscle
Skeletal muscle
Nerve
Pyknosis
Nuclear condensation
Karyorrhexis
Fragmentation
Karyolysis
Dissolution
What reaction is catalyzed by superoxide dismutase?
2O2- + 2H-> H2O2 +O2
What reaction is catalyzed by catalase?
2H2O2 -> O2 + 2H2O
What reaction is catalyzed by glutathione peroxidase?
2OH- -> 2H2O
Metaplasia
Replacement of mature cell type by another mature cell type
What are the characteristics of necrosis?
- Always pathologic
- External
- Contents leak out
- Damage to adjacent tissue
What are the characteristics of apoptosis?
- Physiological or pathological
- Directed cell death
- Nuclear dissolution, intact membrane
- No damage to adjacent tissue
Hyperplasia can lead to cancer. What is the exception?
Benign prostatic hyperplasia
What are the causes of metaplasia?
Chronic inflammation and irritation
What type of metaplasia changes cells from columnar to squamous?
- Bronchus of smoker
- Respiratory epithelium in vitamin A deficiency
- Uterine cervix inflammation
What type of metaplasia changes squamous to columnar?
Distal esophogus exposed to acid (Barret’s esophagus)
What is the site, morphology, and cause of fat change (steatosis)?
Site: Liver (most common), heart, kidney
Morphology: Well defined vacuoles in cytoplasm
Cause: Toxin (alcohol, drugs, CCl4), diabetes, obesity, protein malnutrition, hypoxia
By what mechanisms can alcohol result in fat change?
Hepatoxin alters mitochondrial/microsomal function, increased lipid synthesis/ reduce breakdown.
By what mechanism can CCl4 and protein malnutrition result in fat change?
Damage/ reduce apoprotein synthesis
NOTE: Apolipoproteins are proteins that bind lipids to form lipoproteins. They transport lipids in blood, cerebrospinal fluid and lymph.
By what mechanism does hypoxia result in fat change?
Inhibits fatty acid oxidation
Xanthomas
- Cholesterol in macrophages (acquired and hereditary hyperlipidemias)
- Yellow nodules, skin tendon
Cholesterolosis
abnormal deposits of cholesterol esters in macrophages in gall bladder
Mallory bodies
- made up of intermediate cytokeratin 8/18 filament proteins
- Accumulate in the cytoplasm of hepatocytes
NOTE: these bodies are classically seen in people suffering from alcoholic liver disease
___________ can accumulate in the brain and cause Alzheimer’s disease.
Neurofilaments
What is the morphology of hyaline change?
Homogenous, pink glassy appereance
What is the morphology of glycogen change?
- Vacuoles in cytoplasm-dissolves in fixative
- Periodic Acid Schiff (PAS) stain positive
What is the morphology of abnormal deposition of calcium in tissue?
- Amorphous
- Basophilic (blue)
- Granular
- Laminated (psammoma bodies)
- May cause organ dysfunction
What is the morphology of dystrophic calcification?
- Localized- necrotic tissue or aged/ damaged tissue
- Normal calcium metabolism
What is the morpholog of metastatic calcification?
- Deposits in normal tissue
- Hypercalcemia-disturbance in calcium metabolism
What are the possible causes of metastatic calcification?
- Hypercalcemia
- Bone reabsorption
- Vitamin D disorders
- Renal failure
Characteristics of coagulative necrosis
- Cell outline perserved
- Eosinophilic cytoplasm
- NO NUCLEUS
- Cause: Ischemia
*Doesn’t happen in brain
Characteristics of liquefactive necrosis
- Necrotic debris
- Enzymatic digestion
NOTE: Enzymes from the microglial cells liquify the brain. Enzymes from neutrophils liquefy tissue. Enzymes from pancreas liquefy the pancreas.
What is the cause of fat necrosis?
Calcium deposition
Fibrinoid necrosis
Necrosis of blood vessels
Symptoms of Coagulative Necrosis
- EKG changes
- Chest pain
- Elevated enzymes
Where does gangrenous necrosis commonly occur?
Intestine, colon, limbs
What is the major cause of caseous necrosis?
TB infection
NOTE: This is a macrophage-mediated necrosis
What are the causes of fat necrosis?
- Acute pancreatitis (pancreas, omentum)
- Trauma (breast)
What is the pathogenesis of fat necrosis?
- Enzymatic fat digestion w/ calcium depostition (saponification)
- Dystrophic calcification (when calcium deposits on necrotic tissue)
REMEMBER: In dystrophic calcification calcium is normal. in metastic calcification, calcium is not normal (hyperparatyroidism)
What is the pathogenesis of fibrinoid necrosis?
- Immune complex deposition vessel wall
- inflammation, leakage of fibrin