Healing and repair

Question 1

Resolution

Answer 1

Initiating factor (whatever was damaging the tissue) is removed.
Tissue is undamaged or able to regenerate

Question 2

Repair

Answer 2

Initiating factor is still present

Tissue is damaged and unable to regenerate

Question 3

Characteristics and examples of repair

Answer 3

Replacement of damaged tissue by fibrous tissue
collagen produced by fibroblasts
Examples:
heart after myocardial infarction
Brain after cerebral infarction
Spinal cord after trauma

Question 4

Which is better resolution or repair?

Answer 4

Resolution.
Repair happens when theres damage daily over a time period.
Resolution happens when theres a single assault.
Repair results in sclerosis - (permanent damage)

Question 5

What is sclerosis?

Answer 5

The stiffening of a structure, usually caused by the replacement of the normal organ-specific tissue with connective tissue.

Question 6

Liver resolution

Answer 6

Liver can regenerated does throughout our lives.
e.g. tumour - remove part of the liver containing the tumour and a full healthy liver will grow back.
paracetamol overdose - single assault so regeneration

Question 7

Liver repair

Answer 7

Alcoholism - damage daily over time.

Leads to liver fibrosis which eventually leads to sclerosis?

Question 8

Lobar pneumonia

Answer 8

This is damage to one lobe of the lung. As it affects a single lobe it can be resolved. Pneumocytes that line the alveoli can regenerate.

Question 9

Skin wounds

Answer 9

Fibrosis on repair.
Road rash (swallow) - heals well as hasn't removed all of the epithelium.

Question 10

Skin wounds healing of 1st and 2nd intention

Answer 10

1st - cut goes right through, doesn’t completely heal. erg, knife wounds.
Wound filled with fibrin, fibroblasts make collagen.
2nd - wound that cannot be suture. More fibroblasts producing collagen. Granulation occurs

Question 11

What is granulation?

Answer 11

Granulation tissue is the new connective tissue and microscopic blood vessels that forms on the surface of a wound during the healing process.

Question 12

What types of cells can regenerate?

Answer 12

Hepatocytes (liver cells)
Pneumocytes (lining alveoli)
All blood cells
Gut epithelium
Skin epithelium
Osteocytes (bone remodelling)

Question 13

What types of cells cannot regenerate?

Answer 13

Myocardial cells

Neurones