Cellular Damage Inflammation/healing

Question 1

Define hyperplasia

Answer 1

Increase in the number of cells
Can only happen in organs that can regenerate cells

Question 2

Physiological examples of hyperplasia

Answer 2

Compensation after partial hepatectomy

Question 3

Pathological example of hyperplasia

Answer 3

Abnormal androgen response in BPH

Question 4

Define hyper trophy

Answer 4

Increase in mass of each cell resulting in a larger organ overall

Question 5

Physiological example of hypertrophy

Answer 5

Uterus in pregnancy

Question 6

Pathological example of hyper trophy

Answer 6

Cardiac myocytes aortic stenosis

Question 7

Define atrophy

Answer 7

A decrease in mass of cell

Question 8

Physiological examples of atrophy

Answer 8

Uterus after birth

Question 9

Pathological example of atrophy

Answer 9

Disuse, denervation,ischaemia, nutrition, aging, pressure

Question 10

Define metaplasia

Answer 10

A reversible change where the cell type changes

Question 11

Example of metaplasia

Answer 11

Barrotts oesophagus

Question 12

Define necrosis

Answer 12

Cell death after an abnormal stress , it is always pathological

Question 13

Regarding healing by first intention when do neutrophils appear

Answer 13

Within 24 hours

Question 14

With regards to healing by first intention when is neovascularisation maximal

Answer 14

Day 5

Question 15

What accounts for most wound strength

Answer 15

Collagen 1

Question 16

With regards to healing by first intention when is collagen type 3 and type 1 deposited

Answer 16

Type 3 initially
Replaced by type 1 which is stronger

Question 17

Describe platelets

Answer 17

Membrane bound smooth biconvex discs
Do not have a nucleus
Shed from megakaryocytes in bone marrow
Contain alpha and delta granules
Average life span 5-9 days

Question 18

Products produced by macrophages that cause tissue injury and fibrosis

Answer 18

Arachidonic metabilites
Reactive oxygen species
Reactive nitrogen
Proteases
Cytokines
Coagulation factors

Question 19

Factors released by macrophages which cause repair

Answer 19

Growth factor
Fibrogenic cytokines
Angiogrnic factors
Remodelling collagenesis

Question 20

Which cells participate in phagocytosis

Answer 20

Monocytes
Macrophages
Neutrophils
Tissue dendritic cells
Mast cells

Question 21

When does new collagen deposition occur

Answer 21

By day 3 of wound healing

Question 22

With a clean surgical incision wound what is the wound strength by the end of the first week

Answer 22

10%

Question 23

With clean surgical incision what happens to the destroyed dermal appendages

Answer 23

The do not recover

Question 24

What is the first part of fracture healing

Answer 24

Haematoma
Occurs immediately after
Provides a firbin mesh for influx of inflammatory cells

Question 25

What is the second part of fracture healing

Answer 25

Inflammation via degranulation of platelets and inflammatory cells Activate osteoprogenitor cells in periosteum and medullary cavity Osteoclastic and osteoblastic activity

Question 26

What is the 3rd part of fracture healing

Answer 26

Procallus No structural integrity for weight bearing

Question 27

What happens in callus formation in fracture healing

Answer 27

Subperiosteal deposition of trabecular woven bone Maximal girth at week 2-3

Question 28

What are the 3 phases of fracture healing

Answer 28

Reactive Reparative Remodelling

Question 29

What happens in the reactive phase of fracture healing

Answer 29

Haematoma forms immediately Provides fibrin mesh Sets up the framework for the formation of procallus Fracture callus is most often made up of hyaline cartilage and woven bone

Question 30

What happens in the reparative stage of fracture healing

Answer 30

Replacement of hyaline cartilage and woven bone with lamellar bone Replacement of hyaline cartilage is known as endochindral ossification Replacement of woven bone is known as bony substitution

Question 31

What happens in the remodelling stage of fracture healing

Answer 31

Travecular bone replaces lamellar bone The trabecular bone is resorbed by osteoclasts Creates a shallow pit - howships lacuna Osteoblasts deposit compact bone which is remodelled

Question 32

What is healing by first intention - primary union

Answer 32

The wound is clean uninfected surgical incision approximated by surgical sutures Incision involves limited number of epithelial cells and connective tissue cells as well as disruption of epithelial basement membrane continuity

Question 33

What happens within 24 hours of clean virginal suture

Answer 33

Neutrophils appear at wound margins Epidermis at its cut edges thickens because of mitotic activity

Question 34

What happens between 24-48hrs of clean surgical suture wounds

Answer 34

Epithelial spurs develop fishing in the midline beneath the surface scab producing a thin epithelial layer

Question 35

What happens at day 3 of clean surgical suture wounds

Answer 35

Granulation tissues invade the space, collagen appears

Question 36

What happens at day 5 of clean surgical suture wounds

Answer 36

Neovascularization is maximal Collagen fibres bridge the incision Epidermis recovers

Question 37

What happens at week 2 of clean surgical suture wounds

Answer 37

Accumulation of collagen and fibroblasts Decrease in vascularity and inflammatory cells

Question 38

What happens at one month of clean surgical suture wounds

Answer 38

The scar compromises a cellular connective tissue devoid of inflammatory infiltrate covered now by intact epidermis

Question 39

What is healing by secondary intension

Answer 39

Extensive cell and tissue loss Regeneration of parenchyma cells cannot reconstitute the original architecture Abundant granulation tissue

Question 40

What inflammatory reactions do mast cells participate in

Answer 40

Acute and chronic

Question 41

Do mast cells release lysosomes

Answer 41

No

Question 42

With regards to mast cells what does adenosine triphosphate do

Answer 42

Provides the emerge for mast cell degranulation

Question 43

How do burns cause hypovolaemia

Answer 43

Increase in local interstitial osmotic pressure Neurogenic and mediator induced increase in vascular permeability Protein from blood is lost into interstitial tissue Generalised oedema

Question 44

How are neutrophils removed at the end of the inflammatory process

Answer 44

Apoptosis

Question 45

System factor that impacts wound healing

Answer 45

Glucocorticoid excess Diabetes mellitus Blood flow - cvd pvd Nutrition - protein vitamin c