Pathology Flashcards
ATP dependent program cell death
Apoptosis
What enzyme is involved in both Intrinsic and Extrinsic pathways of apoptosis
Caspases
What happens to the cell membrane during apoptosis
Intact without significant inflammation
What is sensitive indicator of apoptosis
DNA laddering
What is DNA laddering
Fragments in multiples of 180bp
What regulates the Intrinsic pathway
Bcl-2 family proteins
Which proteins are the PRO-apoptotic proteins
BAX and BAK
What are the ANTI-apoptotic proteins
Bcl-2 and Bcl-x
Which anti-apoptotic protein keeps the mitochondrial outer membranes impermeable preventing CYTOCHROME C release from the inner mitochondrial matrix
Bcl-2
Over expression of Bcl-2 can lead to
Follicular lymphoma ( t[14;18] )
What is involved in the Extrinsic pathway
- Ligand receptor interactions
2. Cytotoxic CD8+ T-cell mediated (Immune cell)
What happens in Ligand receptor interactions
FasL bind to Fas [CD95 death receptor] on target cell activating caspases or TNF-alpha binding to its receptor
What happens in Cytotoxic CD8+ T cell mediated (Immune cell) pathway
Cytotoxic T-cell release of perforin creates pores and Granzyme B–> activate caspases
Autoimmune Lymphoproliferative syndrome is caused by
Defective Fas-FasL interactions
The histology of this necrosis has cell outline preserved but NO nuclei and increased cytoplasmic binding to Eosin dye
Coagulative necrosis
Where can’t coagulative necrosis occur
Brain
What necrosis is seen in bacteria abscesses and BRAIN infarct
Liquefactive necrosis
Fragmented cells and debris surrounded by lymphocytes and macrophages
Caseous Necrosis
What causes Fat necrosis
Damaged cells release LIPASE to break down triglyceride liberating Fatty acids to bind calcium—-> SAPONIFICATION
How does saponification appear on H&E
Dark blue
Necrosis which causes vessels walls to be THICK and PINK (type 3 HSR)
Fibrinoid
Liquefactive superimposed on coagulative
Wet Gangrenous
What infarct occurs in venous occlusion and tissues with multiple blood supply
Red infarct
Examples of tissue with red infarct
Liver, Intestine, Testes, reperfusion
What is the cause of Reperfusion injury
Free Radicals
Where does Pale (anemic) infarcts occur
Solid Organs with single blood supply (heart, kidney ad spleen)
What is cells are first released during Acute inflammation
- Neutrophile
- Eosinophil
- mast cells
* * Basophil mediated
What are some outcome of acute inflmmation
- Complete resolution
- Abscess formation
- or Progression to chronic inflammation
What cells are first released during chronic inflammation
Mononuclear cells
- monocytes and macrophages
- lymphocytes
- plasma cells
* * Fibroblast mediated
Persistent destruction and repair associated with blood vessel proliferation and fibrosis
Chronic inflammation
Nodular collection of epithelioid macrophages and giant cells
Granuloma
Calcium deposition in abnormal tissues which tend to be localized
Dystrophic calcification
Where does Leukocyte extravasation usually occur
Post capillary venules
Which tissues CANNOT undergo hyperplasia but can only undergo hypertrophy
Permanent tissue (cardiac muscle, skeletal muscle and nerve)
In what condition can a cell undergo hyperplasia but does not increase risk of cancer
Benign Prostatic Hyperplasia (BPH)