Pathology Flashcards
(176 cards)
what pathways does apoptosis have
intrinsic and extrinsic pathways
general occurrences during apoptosis (4)
- eosniphilic cytoplasm
- cell shrinkage
- karyorrhexis (nuclear fragmentation)
- apoptotic bodies
what happens in karyorrhexis?
endonucleases cleave at internucleosomal regions into 180bp fragments
what does radiation therapy do to cells
free radicals and dsDNA breakage –> apoptosis of tumors and surrounding tissue
when does intrinsic pathway apoptosis occur? (3)
- regulating factor taken away from proliferating cells
- after injurious stimuli
- anti/pro apoptotic factor ratio
examples of intrinsic pathway apoptosis (4)
- removal of IL-2 after completed immuno reaction
- radiation, toxins, hypoxia
- BAX and BAK (pro-apoptotic)
- Apaf-1 (pro-apoptotic)
pro-apoptotic factors (3)
BAX
BAK
Apaf-1
anti-apoptotic facotrs (1)
- Bcl-2
What does Bcl-2 do
binds to Apaf-1 and inhibits it so that it cannot release cytochrome C
too much bcl-2?
too little apaf-1 and you get tumorgenesis (ex follicular lymphoma)
what mechanism is extrinsic pathway apoptosis?
- ligand receptor
FasL to Fas (CD95)
CD95?
Fas
thymus negative selection is what pathway of apoptosis
extrinsic pathway
necrosis definitino
enzymation degradation and protein denaturation 2/2 exogenous injury
where does coagulative necrosis occur (3)
tissue supplied by end-arteries
- heart
- liver
- kidney
order of what happens in coagulative necrosis
- proteins degrade first
2. enzymatic degradation
where does liquefactive necrosis occur and when
occurs in CNS 2/2 high fat content
brain bacterial abscess
order of what happens in liquefactive necrosis
- enzymatic degradation from lysosomal release
2. Then protein degradation
when does caseous necrosis occur (3)
- TB
- systemic fungi
- nocardia
acid fast?
where does fatty necrosis occur (2)
- pancreas
2. breast
pancreatitis leads to what?
saponification
fatty necrosis
what does fatty necrosis look like on staining
calcium deposits appear dark blue
what does fibrinoid necrosis look like on stain
amorphous and pink on H&E
where can you see fibrinoid necrosis? (2)
vessels
- vasculitidies (HSP, churg-strauss)
- malignant HTN