Flashcards in Pathology Deck (67):
What is vasodilation mediated by?
Histamine and Nitric oxide
Where are selectins expressed?
Endothelial cell surface
What do integrins bind to?
Cell wall, matrix and other cells
What increases selectin expression?
Histamine and thrombin
What increases VCAM/ICAM?
TNF and interleukin-1
When the cell follows a chemical gradient and moves along it
What are the 5 characteristics of acute inflammation?
Rubor, calor, dolor, tumor and loss of function
Which cells characters acute inflammation?
What is needed for resolution to occur?
Good vascular supply and minimal cell death
Pus formation containing neutrophils, bacteria and inflammatory debris
Restitution or scarring after lots of necrosis
When does scarring occur?
If damage has gone beyond the basement membrane
When is chronic inflammation favoured?
If scarring has occurred, the injury is persistent, there is an infectious agent or it is autoimmune
What is chronic inflammation characterised by?
Lymphocytes and macrophages
Aggregation of epithelioid histiocytes i.e. a big group of macrophages
The mopping up of cells by neutrophils when they die
Progressive scarring where macrophages are replaced by fibroblasts
Increase in cell number - can be physiological or pathological
Examples of pathological hyperplasia
Endometrial hyperplasia or lymph node hyperplasia in response to infection
Is hyperplasia reversible?
Increase in cell size
Reduction in cell size
Two mechanisms by which a cell can die
Necrosis or apoptosis
No energy required and is always pathological
Preserves cell outline - associated with MIs
Associated with TB, granulomatous
No cell structure remains, occurs in the brain (bacterial)
Requires energy and can be pathological or physiological
Programmed cell death
Which signals do death receptors sense?
TNF - inflammatory
Fas - Autoimmune
What initiates extrinsic apoptosis?
What happens in intrinsic apoptosis?
Growth signals from anti-apoptotic cells are removed so Bad and Bak are free to punch holes in the mitochondria
What is p53's role in apoptosis?
Induce it if DNA repair is unsuccessful
Uncontrolled cell proliferation in which continued growth can invade other cells
Autonomous growth without a stimulus
Disordered growth which is not in response to a stimulus
Reversible change from one cell type to another in response to a stimulus
Carcinoma in Situ
Dysplasia affecting the whole of the epithelium
Epithelium change in barrett's oesophagus
Squamous to glandular
Epithelium change in lung cancer
Glandular to squamous
What does radiation do to DNA?
Causes formation of pyridine dimers
What do cells produce to destroy surrounding tissue?
Formation of new blood vessels stimulated by VEGF and PDGF
Dysplastic lesion of glandular epithelial tissue
A gene that is mutated from a gene for normal cell growth
Tumour supressor gene
A type of gene that makes a tumour suppressor protein - mutations in this can cause cancer
Where does p53 act in the cell cycle?
At G1 to pause the cell cycle by increasing p21
What is the function of PTEN?
Increases transcription of p27
Histopathology of malignancy
High N:C ratio
Hyperchromasia - increased DNA
Malignancy of the epithelium
Malignancy of glandular tissue
Benign lesion of glandular tissue
Benign lesion of squamous cells
Malignancy of squamous cells
Squamous cell carcinoma SCC
Weight loss in cancer
4 "stages" to atheroma development
What increases the expression of leukocyte adhesion molecules?
What increases the expression of endothelial cell adhesion molecules and ICAM?
Formation of a blood clot which blocks the artery
Balloon like swelling in the wall of an artery
Tear in the inner wall of an artery, blood splits layers of wall
Which blood vessels do arteriosclerosis and atherosclerosis affect?
Arteriosclerosis - arterioles
Atherosclerosis - elastic artery walls
Solid mass of blood clotting factors formed inside the vessel walls
Vessel wall injury
Blood flow - turbulence or stasis
Blood constituents - platelets
A mass of material in the vascular system which moves from its site of origin and blocks the vessel at a distant site