L1 - Cell Injury and Cell death I

Question 1

Give three causes of cell death, an example is physical agents such as trauma

Answer 1

Chemical agents - alcohol
Microorganisms
Dietary insufficiency and excess
Genetic abnormalities 
Hypoxia

Question 2

What’s the difference between cytology and histology

Answer 2

Cytology - non-invasive. Cheap. Used for preliminary tests and normally involves single cells

Histology - invasive. Expensive.
Used for definitive testing
Looks at tissues as a whole

Question 3

Discern between ‘stage’ and ‘grade’ of cancer

Answer 3

Grade - how well differentiated the cancer is. If it’s well differentiated it is normally easier to treat. Well differentiated - low grade. ‘How well does it resemble the parent tissue?’

Stage - refers to spread of the cancer. Whether there are metastises, how many lymph nodes are involved etc

Question 4

Autolysis is self digestion in cells, this occurs when cells are removed because the blood supply is cut off, how do we block this chemical process and preserve cellular architecture?

Answer 4

Fixatives - e.g. formalin

Question 5

What do we have to suspend tissue in so that we can get very thin slices of it?

Answer 5

Paraffin wax

Question 6

What does a) haematoxylin and b) eosin stain, and what colours do they go?

Answer 6

A) nucleic acids - blue

B) proteins and cytoplasm - pink

Question 7

Explain the principles behind immunohistochemistry

Answer 7

This can be used to identify any material which is antigenic. We created an antibody specific to the antigen and use it to identify the antigenic material. The anitbody will be linked to a fluorescent or precipitating material

Question 8

When would we use frozen sections?

Answer 8

Intra-operatively when we want a quick result