Pathology Flashcards
What occurs when the p53 gene is lost?
Cancer
Name a type of pathology that is a silent injury in which dividing cells are more susceptible and permanent cells more resistant.
Nuclear DNA damage
What inactivates free radicals?
Dimutase
What protects against free radicals such as superoxide?
Anti-oxidants
What is necrosis?
Death of tissues
Name 6 patterns of necrosis
- Coagulative
- Colliquative
- Caseous
- Gangrenous
- Fibrinoid
- Fat necrosis
What disorder involves a loss of function mutation, gene encodes enzyme in a metabolic pathway and is usually autosomal recessive?
Inherited metabolic disorders
Name one inherited metabolic disorder?
Phenylketonuria - deficiency of phenylalanine hydroxylase
What test can be used for phenylketonuria?
Guthrie test
Name two chronic inflammatory diseases?
Crohn’s and Rheumatoid arthritis
What two chemical mediators are known to produce pain?
Histamine and bradykinin
What two pressures lead to the formation of fluid exudate?
Increased hydrostatic pressure
Decreased osmotic pressure
Name two components of fluid exudate?
Proteins including immunoglobulins and fibrinogen
What is neutrophil accumulation in the extracellular space a diagnostic feature of?
Acute inflammation
What type of cell: kills organisms, degrades necrotic tissue, ingests offending agents, produces chemical mediators, produces toxic oxygen radicals and produces tissue damaging enzymes?
Neutrophils
What 3 substances increase leucocyte surface adhesion molecule expression?
- Complement component C5a
- Leukotriene B4
- Tumour Necrosis Factor (TNF)
What 3 substances increase endothelial cell expression of adhesion molecules to which neutrophils bind?
- IL-1
- Endotoxins
- Tmour Necrosis Factor
What process allows neutrophils to find the inflammatory stimulus?
Chemotaxis
What substance which is a vaso dilator is released by mast cells, eosinophils, basophils and platelets?
Histamine
What 3 things stimulate the release of histamine?
C3a
C5a
Neutrophils
Where is serotonin present in high concentration?
Platelets
What does serotonin do to vascular permeability?
Increases it
What are leukotrienes synthesised from?
Arachidonic acid
What type of hypersensitivity are leukotrienes involved in?
Type I hypersensitivity
What substance increases vascular permeability and stimulates platelet aggregation?
Prostaglandins
Name 3 major opsonins?
Fc fragment of IgG
C3b
Collectins
After ohagocytosis what do neutrophils undergo?
Apoptosis
What name is given to a collection of pus surrounded by a membrane of sprouting capillaries, neutrophils and occasional fibroblasts?
An abcess
What does repair and organisation of tissues result in?
Fibrosis
What does resolution mean?
The complete restoration of the tisseus to normal after an episode of acute inflammation
What is an osteomyelitis?
A chronic abcess which is extremely difficult to eradicate
What term is given to an inflammatory process in which lymphocytes, plasma cells and macrophages predominate?
Chronic inflammation
What does the formation of granulation tissue result in?
Fibrosis
Give 3 examples of primary chronic inflammation?
- Tuberculosis
- Leprosy brucellosis
- Viral infections
What crystals are important in gout?
Urate crystals
What is ulcerative colitis an example of?
Primary chronic inflammation
Name a primary granulomatous disease?
Sarcoidosis
What macroscopic appearance of chronic inflammation occurs when the mucosa is breahed, the base lined by granulation tissue and fibrous tissue extends through the muscle layers?
Chronic ulcer
What granulomatous disease has caseous necrosis?
Tuberculosis
Macrophages are activated on migration to an area of inflammation by what two factors?
Macrophage activation factors (MAF)
Migration inhibition factor (MIF)
What is the name given to an aggregate of epithelial histiocytes?
A granuloma
What is a histiocyte?
A macrophage present in connective tissue
What might the appearance of granulomas be augmented by?
The presence of caseous necrosis or conversion into histiocytic giant cells
What organism can cause TB which is an aerosol spread from infected cattle or from milk?
M. bovis
What type of lesions does M.bovis initially cause?
Intestinal/tonsillar lesions
What vaccination is given to protect against TB?
BCG vaccination, following a negative heaf test
What is suppuration?
The formation of pus
What is organisation of tissues?
Replacement of tissues by granulation tissue
What are macrophages and fibroblasts characteristic of?
Chronic inflamamtion
Name an aquired metabolic disorder?
Diabetes
Which type of diabetes mellitus is insulin dependent?
Type I