Cell Injury and Cellular Adaptation Vocabulary Flashcards

Comprehensive vocabulary flashcards covering the key terms, morphological patterns, mechanisms of injury, necrosis styles, apoptosis pathways, cellular adaptations, and pathological calcifications from the lecture notes.

Cell Injury

A sequence of events that occurs if the limits of cellular adaptive capability are exceeded or no adaptive response is possible.

Free Radicals

Chemically unstable chemical species with a single unpaired electron in an outer orbital that readily react with inorganic and organic molecules.

Superoxide Dismutase (SOD)

An enzyme that neutralizes free radicals by converting superoxide via the reaction $2O_2^{\bullet} + 2H^+ \rightarrow O_2 + H_2O_2$.

Lipid Peroxidation of Membranes

A mechanism of free radical-induced injury where oxygen free radicals attack double bonds in polyunsaturated membrane lipids.

DNA Fragmentation

A free radical-induced injury mechanism where free radicals react with thymine in nuclear and mitochondrial DNA to produce single-strand breaks.

Protein Cross-Linking

A process induced by free radicals that promotes sulfhydryl-mediated cross-linking, leading to increased protein degradation or loss of enzymatic activity.

Cloudy Swelling

An early form of cellular swelling caused by failure of the cellular sodium pump, allowing excess $Na^+$ to enter cells and increase intracellular water.

Hydropic Degeneration

A severe form of cloudy swelling (vacuolar degeneration) that occurs when cells are incapable of maintaining ionic and fluid homeostasis, such as during hypokalemia.

Fatty Change (Steatosis)

The abnormal appearance or accumulation of lipid vacuoles within the cytoplasm of parenchymal cells.

Zenker's Waxy Hyaline Masses

A specific pattern of hyaline degeneration associated with typhoid fever or Weil's disease (leptospirosis).

Mallory Bodies

Hyaline inclusions found in hepatocytes associated with nutritional cirrhosis.

Russel Bodies

Hyaline structures associated with chronic inflammation.

Crooke's Hyaline Bodies

Hyaline changes in pituitary cells associated with Cushing's syndrome.

Councilman Bodies

Apoptotic hyaline bodies seen in yellow fever and viral hepatitis.

Mucinous Degeneration

The presence of an excessive amount of mucous in an unusual anatomical location.

Necrosis

The spectrum of morphologic changes that follow cell death in living tissue, resulting from progressive degradative action of enzymes on lethally injured cells; it is always a pathologic process.

Pyknosis

A pattern of nuclear change during cell death characterized by nuclear shrinkage and increased basophilia, taking on an appearance similar to an ink drop.

Karyolysis

A nuclear alteration characterized by progressive fading of the basophilic staining of the nuclei, resulting in ghost nuclei.

Karyorrhexis

A nuclear alteration during cell death in which the pyknotic nucleus breaks up into many smaller fragments.

Coagulative Necrosis

A type of necrosis that is pale grossly, and histologically displays preserved cell architecture with a ghost-like appearance.

Liquefactive Necrosis

A pattern of necrosis characterized grossly as soft, and histologically by complete destruction of tissue architecture with no detail preserved.

Caseous Necrosis

A type of necrosis that appears cheesy or crumbly grossly, and histologically presents as messy tissue with abundant macrophages.

Gangrenous Necrosis

A form of necrosis that is dry and dark grossly, and histologically ghost-like, often accompanied by large saprophytic bacteria.

Enzymatic Fat Necrosis

A pattern of necrosis that appears chalky grossly, and histologically shows amorphous pink and blue regions with dead and dying fat cells.

Apoptosis

A pathway of programmed cell death characterized by activation of cellular enzymes that degrade the cell's own nuclear DNA and proteins without inducing an inflammatory response.

ER Stress

Excessive intracellular accumulation of unfolded or misfolded proteins in the endoplasmic reticulum, which triggers apoptotic cell death.

Intrinsic Pathway of Apoptosis

The mitochondrial pathway of apoptosis activated by intracellular signals and regulated by the permeability of the mitochondrial membrane via Bcl-2 family proteins.

Extrinsic Pathway of Apoptosis

The death receptor-initiated pathway of apoptosis activated by extracellular signals binding to cell surface receptors such as TNFR1 or Fas (CD95).

Atrophy

A cellular adaptation characterized by shrinkage in cell size due to the loss of cellular substance.

Hypertrophy

A cellular adaptation defined as an increase in the size of individual cells due to the gain of cellular substance.

Hyperplasia

A cellular adaptation characterized by an increase in the overall number of indigenous cells in an organ or tissue.

Metaplasia

A reversible cellular adaptation in which one adult cell type (epithelial or mesenchymal) is replaced by another adult cell type better suited to tolerate an abnormal environment.

Dysplasia

Disordered cellular development characterized by architectural disorientation and cellular pleomorphism (lack of uniformity of individual cells).

Dystrophic Calcification

The abnormal deposition of calcium phosphate in dead or dying tissues occurring despite normal serum calcium levels.

Metastatic Calcification

The deposition of calcium in previously normal tissues as a direct consequence of hypercalcemia.