Cell Death

Front 1

necrosis

Back 1

gross and microscopic manifestations that indicate cell death in living tissue -

enzyme degradation mainly -

always pathological

Front 2

apoptosis

Back 2

programmed cell death -

genetically controlled -

eliminates unwanted cells -

physiological and pathological

Front 3

autolysis

Back 3

degradation of cell and contents caused by own enzymes

Front 4

heterolysis

Back 4

degradation of cell and contents by extrinsic enzymes

Front 5

putrefaction

Back 5

lysis of dead tissue by bacterial enzymes

Front 6

necrotic changes

Back 6

hypereosinophilic cytoplasm (RNA loss + coagulated proteins),

glycogen loss (smaller cell, more pink),

nuclear changes

Front 7

morphologic necrotic types

Back 7

coagulative,

liquefactive,

caseous,

fat,

fibrinoid,

gangrenous,

gummatous

Front 8

coagulative necrosis

Back 8

microscopic:

cell outline and tissue architecture preserved,

nucleus loss,

increased eosinophilia;

macroscopic:

dense and dry appearance,

white-grey when cut

Front 9

liquefactive necrosis

Back 9

microscopic:

complete loss of cell and tissue structure,

no cell outlines,

neutrophils;

macroscopic:

soft and filled with fluid

Front 10

caseous necrosis

Back 10

no cell outlines or tissue architecture but firm consistency;

macroscopic:

yellowish-white, cheese-like from lipid release from cell walls;

microscopic:

eosinophilic material surrounded by inflammatory cells

Front 11

enzymatic fat necrosis

Back 11

focal areas of fat destruction, due to pancreatic enzyme actions;

pale outlines, hematoxylin stains calcium blue; pancreatitis --> fatty acids + Ca = saponification and chalky white calcium deposits

Front 12

traumatic fat necrosis

Back 12

trauma --> healing by fibrous tissue and calcification

Front 13

fibrinoid necrosis

Back 13

immunologic injury;

smudgy pink staining of fibrin-like protein material

Front 14

gangrenous necrosis

Back 14

loss of blood supply = form of infarction;

dry (coagulative)

wet (with infection and liquefactive);

in lower limbs and bowels

Front 15

infarction

Back 15

localized area of tissue necrosis from loss of or reduced blood supply;

coagulative in most tissues,

liquefactive in brain

Front 16

Physiologic apoptosis

Back 16

embyrogenesis,

hormone-dependent involution,

thymus involution in adults,

cells programmed to die (epidermis, gut), inflammatory cell destruction

Front 17

Pathologic apoptosis

Back 17

toxin induced,

councilman bodies,

psammoma bodies,

tumor cell death by cyt T cells,

neuronal loss in Alzheimer's,

HIV+ T-lymphocyte death

Front 18

councilman bodies

Back 18

dead hepatocytes in viral hepatitis

Front 19

psammoma bodies

Back 19

apoptosis of neoplastic cell with subsequent calcification

Front 20

neoplastic

Back 20

abnormally growing cell

Front 21

apoptosis initiation

Back 21

extrinsic or intrinsic caspase activation,

gene regulation

Front 22

apoptosis execution

Back 22

cell death caused by activated enzymes

Front 23

removal of cells in apoptosis

Back 23

cytoplasmic buds form on membrane that contain nuclear fragments,

mitochondria and protein fragments

Front 24

extrinsic pathway

Back 24

receptor-ligand interactions:

TNF + TNF1, Fas + Fas ligand --> caspase activation

Front 25

intrinsic pathway

Back 25

withdrawal of hormones or growth factors, damage to DNA --> release of cyt c --> caspase activation

Front 26

Bcl-2

Back 26

inhibits apoptosis by preventing release of cyt c from mitochondria

Front 27

p53

Back 27

tumor suppressor gene = stimulates apoptosis; elevated by DNA injury and pauses cell cycle to repair; activates Bax if repair is impossible

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Bax

Back 28

stimulates apoptosis

Front 29

caspases

Back 29

group of proteases that mediates execution phase

Front 30

executioner caspases

Back 30

activate endonucleases (DNA degradation) and proteases (cytoskeleton breakdown)

Front 31

apoptotic bodies

Back 31

broken off cytoplasmic buds

Front 32

phagocytosis

Back 32

absorbtion of apoptotic bodies by adjacent cells or macrophages

Front 33

apoptotic morphology

Back 33

eosinophilic cytoplasm,

pyknotic nucleus,

small cells,

apoptotic bodies,

phagocytosis,

lack of inflammatory response

Front 34

dysregulated apoptosis

Back 34

too much or too little apoptosis;

decreased = cancers, autoimmunity;

increased = neurodegenerative, death of infected cells (AIDS)

Front 35

enzyme markers of cell death

Back 35

AST aspartate aminotransferase (liver necrosis),

ALT alanine aminotransferase (liver necrosis),

CK-MB creatine kinase MB (AMI, myocarditis),

amylase and lipase (pancreatitis)