Cell Injury Flashcards
What are the biochemical features of apoptosis?
- DNA breakdown into oligonucleosomes
- Caspase cleavage of nuclear scaffold, cytoskeletal proteins and activate DNAases
- Phagocytic recognition via surface phospholipids and opsonins
Promoter apoptotic genes
Bax
Bak
Bim
Bad gene
P53 gene
Inhibitor apoptotic genes
Bcl-2
Bcl-xl
Inhibited apoptosis could lead to…
Cancer and autoimmune diseases
Increased pathological apoptosis is seen in…
Neurodegenerative diseases
Features of irreversible cell injury
Lysis of ER
pyknosis, karyorrhexis, and karyolysis
Swelling of mitochondria and lysosome
Rupture of the lysosome
Defects in mitochondrial cell membrane
Large densities
Features of reversible cell injury
Blebbing
Mitochondrial and ER swelling
Small densities
Mitochondrial rarefaction
Autophagy by lysosomes
Myelin figures
Distortion of microvilli
Clumping of nuclear materials
Dispersion of ribosomes
Fatty changes
Polysome dissociation
How do bacterial infections cause necrosis? What type? What is the fluid formed?
Inflammatory cells release hydrolytic cells that digest all the dying cells into a viscous liquid.
The type of necrosis is liquefactive necrosis.
The fluid formed is pus.
Does basophilia increase or decrease in cell injury?
Basophilia decreases because of the breakdown of DNA and RNA, which are basophilic.
Fibrinoid necrosis is seen in…
Malignant hypertenstion
Are caspases directly or indirectly involved in DNA breakdown?
They’re indirectly involved. Caspases activate DNAses, which then breakdown the DNA.
Is coagulative necrosis seen in stroke?
It is not. It only follows hypoxia in all tissues except CNS tissues.
