Tissue Repair

Question 1

Acute or Chronic?

-Onset of injury occurs in seconds or minutes.

Answer 1

Acute

Question 2

Acute or Chronic?

-Onset of injury occurs in days/weeks/months/years

Answer 2

Chronic

Question 3

Acute or Chronic?

-Vascular response is dilation/ increased flow. Increased permeability leading to transudate or exudate

Answer 3

Acute

Question 4

Acute or Chronic?
-Vascular response results in variable persistence of dilation and “leakiness”. Endothelial cell activation: ready to proliferate if necessary

Answer 4

Chronic

Question 5

Acute or Chronic?

-Inflammatory cells are neutrophils

Answer 5

Acute

Question 6

Acute or Chronic?

-Inflammatory cells are macrophages or lymphocytes

Answer 6

Chronic

Question 7

Where is the source of the cells of acute inflammation?

Answer 7

Peripheral blood

Question 8

Where is the source of the cells of acute inflammation?

Answer 8

Sentinel/ local cells in tissues

Peripheral blood

Question 9

Repair is stimulated during which phase?

Answer 9

Chronic

Question 10

True or False: One can have “chronic” inflammation without a distinct “acute” phase

Answer 10

True

Question 11

What cell is responsible for:

Secretion of growth factors

Answer 11

Macrophages

Question 12

What cell is responsible for:

Neovascularization

Answer 12

Endothelial cells

Question 13

What cell is responsible for:

Collagen deposition

Answer 13

Fibroblast/ Myofibroblast

Question 14

What cell is responsible for:

Collagen remodeling / retraction

Answer 14

Fibroblast

Question 15

What cell is responsible for:

Re-epithelialization/ Regeneration

Answer 15

Epithelial cells / hepatocytes

Question 16

Describe the appearance of granulation tissue.

Answer 16

Pink, soft granular appearance grossly.

Question 17

What is granulation tissue comprised of?

Answer 17

Fibroblasts, new capillaries (angiogenesis), loose extracellular matrix, and inflammatory cells (predominantly macrophages)

Question 18

Define reepithelization

Answer 18

Cells rapidly replaced by proliferation of residual cells provided underlying basement membrane is intact

Question 19

Name two places where reepithelization can be found

Answer 19

GI mucosa and skin

Question 20

Describe regeneration.

Answer 20

Triggered by cytokines and growth factors in response to loss of liver mass and/or inflammation. May occur by proliferation of surviving hepatocytes and/or repopulation from progenitor cells

Question 21

Define and describe normal scar formation.

Answer 21

Angiogenesis > Granulation-tissue > Maturation and reorganization of fibrous tissue (remodeling) > Stable fibrous scar

Question 22

What is the initial scar composed of?

Answer 22

Collagen type III

Question 23

What is the scar remodeling composed of?

Answer 23

Collagen type I

Question 24

What is a pathogenic scar?

Answer 24

Accumulation of excessive amounts of collagen

Question 25

What is a hypertrophic scar?

Answer 25

A scar that is outside the boundaries of injury/ regresses

Question 26

What is a keloid?

Answer 26

Boundaries of injury / persist

Question 27

What local factors can adversely influence repair?

Answer 27

Infection Persistence of insult Trauma

Question 28

What systemic factors can adversely influence repair?

Answer 28

Nutritional: protein deficiency, vitamin C deficiency Metabolic: diabetes, glucocorticoids, venous drainage impairment