regeneration and repair

Question 1

describe resolution

Answer 1

the initiating factor removed
tissue undamaged or able to regenerate
e.g liver- needs to be just enough liver left so the patient doesn’t die from liver failure

Question 2

describe repair

Answer 2

Initiating factor still present
Tissue damaged and unable to regenerate
replacement of damages tissue by fibrous tissue

Question 3

alcoholic liver damage

Answer 3

liver damaged everyday so never gets a chance to properly regenerate so repairs instead so fibrous tissue forms around it and then you get cirrhosis

Question 4

lobar pneumonia

Answer 4

often affects just one lobe
really distinct
bacteria strep pneumonia
do not know cause
don’t get damage to alveoli walls so can restore
alveoli filled with neutrophil polymorphs ( acute inflammation) rather than air

Question 5

what does it mean by healing by 1st intention

Answer 5

edges of skin all together
heals nicely
no infection
forms scar that red initially due to capillaries and then white due to collagen
Incision -> exudation of fibrinogen -> weak fibrin join -> epidermal regrowth and collagen synthesis -> strong collagen join

Question 6

healing by 2nd intention

Answer 6

traumatic wounds
loose some skin
takes longer as blood vessels and cells have to grow in from either side
granulation tissue
Phagocytosis to remove any debris
Granulation tissue to fill in defects and repair specialised tissues lost
Epithelial regeneration to cover the surface

Loss of tissue -> granulation tissue -> organisation -> early fibrous scar -> scar contraction

Question 7

in repair what produces collagen

Answer 7

fibroblasts

Question 8

examples of repair

Answer 8

–heart after myocardial infarction
–brain after cerebral infarction
–spinal cord after trauma

Question 9

name 6 cells that regenerate

Answer 9

• hepatocytes
• pneumocytes
• all blood cells
• gut epithelium
• skin epithelium
• osteocytes

Question 10

name 2 cells that don’t regenerate

Answer 10

• myocardial cells
• neurones

Question 11

Man aged 30 takes a large overdose paracetamol overdose and doesn’t come to hospital for 2 days. He spends a few days on ITU with liver failure but then recovers.
What will be happening in his liver - resolution or repair?

Answer 11

only one overdose
as long as he doesn’t die of liver failure his liver will regenerate.
will recover
-RESOLUTION

Question 12

A child aged 3 falls off a climbing frame onto his hand, he fractures his clavicle. He has his arm in a sling for 4 weeks and is very good about keeping it in the sling
What will be happening in his clavicle - resolution or repair?

Answer 12

in sling all time- should go back to normal

RESOLUTION

Question 13

A child aged 3 falls off a climbing frame onto his hand, he fractures his clavicle. He has his arm in a sling for 4 weeks but won’t keep the sling on and moves his arm a lot
What will be happening in his clavicle - resolution or repair?

Answer 13

can only join back together if ends of bone and immobilised
repair

Question 14

what are abrasions?

Answer 14

the most superficial skin wounds e.g road rash

Question 15

describe the steps of getting an abrasion and the healing process

Answer 15

Normal skin -> abrasion -> scab formed over surface -> epidermis growing out from adnexa, produced by scab -> thin confluent epidermis -> final epidermal regrowth

Question 16

describe organisation

Answer 16

is the process whereby specialised tissues are repaired by the formation of mature fibrovascular connective tissue.
It occurs by the production of granulation tissue and the removal of dead tissue by phagocytosis.

Question 17

describe granulation tissue

Answer 17

is a repair phenomenon, it is loops of capillaries supported by myofibroblasts which actively contracts to reduce wound size; this may result in a structure later.