Pathology - Inflammation Flashcards
define aetiology
causative element in disease
necrosis is said to be the death of tissue, pathological and elicits adjacent tissue response. State the patterns of necrosis (6), and example of each
coagulative - proteins coagulate, preserves cell (MI)
colliquative - necrotic material softens and liquefies (Pus) no cell structure (Brain necrosis)
caseous - cheese like (TB)
gangrenous - necrosis followed by infection, anaerobic bacteria may grow
fibrinoid - fibre deposition (malignant hypertension)
fat necrosis - lypase releases fatty acids frrom triglYs, forms white chalky solids with calcium (acute pancreatitis)
necrosis - requires energy?
no
t/f apoptosis may be physiological
true, can be part of normal growth as well as pathological
P53 is a protein and if lost can lead to the development of
cancer
what does p53 stimulate if DNA cannot be repaired, using what enzyme to induce
apoptosis
caspases
function of telomeres
adds on TTAGGG to chromosomes (get smaller after each division)
prevents cell death
how does cancer interact with telomeres
reactivates to allow continual division
2 factors which may cause a loss of membrane integrity
ion pump failure
- disruption of membrane
lipid alteration
- cross-linking of membrane proteins
free radicals (O2 particular) cause a chain reaction leading to lipid peroxidation, what is this and what does it do
free radicals steal electrons from lipids, leading to cellular breakdown by loss of membrane integrity
what protects against radicals
anti-oxidants
what 5 things can form radicals
drugs o2 toxicity reperfusion injury inflammation intracellular killing of bacteria
acute inflammation can be divided into the vascular phase and the exudative/cellular phase, outline each
vascular - dilation and incr. permeability
exudative - fluid and cells escape from permeable venules
what can be used as a diagnostic feature of an acute inflammation
concentration of neutrophils in extracellular space
beneficial effects of acute inflammation
toxin dilution antibodies enter fibrin formed drug transport oxygen/nutrient delivery immune response
adverse effects of acute inflammation
digestion of normal tissue
swelling - incr pressure
may develop inappropriately (type `1 -asthma)
what causes the heat characteristic associated with inflammation
increased blood flow through region
define margination
loss of intravascular fluid and increased plasma viscosity
allows neutrophils into plasma (venules only)
3 molecules which increase surface adhesion molecule expression
TNF-alpha
Complement C5a
Leukotriene B2
IL-1Endotoxins
TNF
these all increase expression of
adhesion molecules by endothelial cells
what stimulates release of histamine by mast cells
C5a and C3a
lysosomal proteins released by neutrophils also
2 functions of prostaglandins
incr vascular permeability
stimulate platelet aggregation
serotonin
increases vascular permeability
define suppuration
formation of pus
