Pathology 1 - Intro Flashcards
Define ‘disease’
A pathological condition of a body part, organ or system characterised by an identifiable group of signs/symptoms
What is autolysis?
Self-digestion of tissues that occurs when the blood supply is cut off
What are fixatives?
Chemicals which inactivate tissue enzymes and denature proteins, prevent bacterial growth and harden tissue
What is the most commonly used fixative?
Formalin (formaldehyde in water)
How are the tissue samples stored while they are fixed?
They are put in ‘cassettes’ which have holes in, then placed in racks in formalin
What is the tissue embedded in so that thin sections can be cut?
It is embedded in paraffin wax
How is paraffin wax inserted inside the cells?
- Dehydration using alcohol in a vacuum so water is drawn out of the cells
- replace alcohol with xylene which mixes with wax
- replace xylene with molten paraffin wax
What is used to cut very thin sections of tissue?
A microtome
What is the tissue usually stained with?
H&E
Give some examples of things that can be identified using immunohistochemistry
- Actin
- Cadherins
- Hormone receptors
- Her2 receptor
- Microorganisms
What are cytokeratins?
A family of intracellular fibrous proteins present in almost all epithelia. They can give info about the primary site of a carcinoma
