58-Resolution and Repair

Question 1

How do you downregulate inflammation

Answer 1

Stop proinflammatory stimuli
Increase lipoxin
Nitric oxide production
Anti inflammatory cytokine secretion (IL-10 and TGF-B)

Question 2

What does lipoxin do?

Answer 2

antifinflammatory, inhibit neutrophil adhesion and chemotaxis
From arachidonic acid, leukocyte enter tissue and leukotrienes get converted to lipoxins

Question 3

What does nitric oxide do

Answer 3

reduce leukocyte recruitment and decrease platelet activation

Question 4

What does cytokine IL10 do

Answer 4

Released by macrophage to down regulate macrophage (negative feedback) for anti inflammation

Question 5

What does TGF-B do

Answer 5

suppress acute inflammation

Question 6

Outcomes of acute inflammation

Answer 6

Complete restitution, no permanent damage, regain function
Tissue replacement (fibrosis)
Progress to chronic inflammation

Question 7

What causes an acute inflammation to progress to chronic

Answer 7

Persistence of injurious agent
interference with healing
autoimmunity

Question 8

Outcomes of chronic inflammation

Answer 8

Healing with or without scar

Tissue damage

Question 9

What does organized mean

Answer 9

In growth of fibroblasts into the blood vessel wall, leads to scarring
A subtype of healing response

Question 10

What is critical to the survival of an organism

Answer 10

Ability to repair damage

Question 11

Functions of inflammatory response

Answer 11

Eliminate insult and tissue damage

Start process of repair

Question 12

2 ways to heal

Answer 12

regeneration and scar formation

Question 13

What is regeneration

Answer 13

Replace damaged cells and return to normal state, mild injury, no damage to underlying tissue

Question 14

What is scar formation

Answer 14

Incapable of regeneration or supporting structures are severely damaged
Deposition of fibrous tissue, severe injury

Question 15

Regeneration depends on what

Answer 15

proliferative ability of cell
Growth factors
Interactions between cells and matrix

Question 16

Type soft proliferative tissues

Answer 16

labile, stable, permanent

Question 17

What are labile tissues

Answer 17

Readily regenerate, continuously dividing
Intact basement membrane
Bone marrow, epithelial, GI

Question 18

What are stable tissues

Answer 18

Normally quiet but can proliferate

parenchyma, endothelial, fibroblasts, smooth muscle

Question 19

What are permanent tissues

Answer 19

Non proliferative
Terminally differentiated
Neurons and cardiac muscle

Question 20

Types of stem cells

Answer 20

Embryonic and adult

Labile tissues

Question 21

Characteristics of adult stem cells

Answer 21

Limited capacity of self renewal

Can only become cell from where it is found

Question 22

What is asymmetric replication

Answer 22

1 daughter cell differentiates and matures

1 cell remains undifferentiated for self renewal

Question 23

what are growth factors

Answer 23

Proteins that stimulate survival and proliferation, migration, and differentiation

Question 24

What produces growth factors

Answer 24

Macrophages and lymphocytes
Except HFG (fibroblasts, stromal cells in liver)
VEGF (mesenchymal cells)

Question 25

What are the growth factors

Answer 25

``` EGF TGF a and b HGF VEGF PDGF FGF ```

Question 26

Types of ECM

Answer 26

Interstitial matrix | Basement membrane

Question 27

What makes up basement membrane

Answer 27

Type 4 collagen laminin proteoglycan

Question 28

What makes up interstitial matrix

Answer 28

fibrillar collagen Elation proteoglycan hyaluronan

Question 29

What does the ECM do

Answer 29

Regulate proliferation, movement, differentiation, reservoir for growth factors, mechanical support TISSUE REGENERATION!! If ECM is destroyed=scar formation

Question 30

When does scar formation occur

Answer 30

Severe or chronic tissue damage to cells or ECM Injury to non dividing cells Replace cells with connective tissue (fibrosis)

Question 31

What is gliosis

Answer 31

Scarring in brain from glial cells (astrocytes)

Question 32

Steps in scar formation

Answer 32

Injury Inflammation Translation tissue Scar formation

Question 33

What is angiogenesis

Answer 33

New vessel growth

Question 34

What is fibrogenesis

Answer 34

Migration and proliferation of fibroblasts and depositing collagen

Question 35

What is granulation tissue

Answer 35

Angiogenesis and fibrogenesis

Question 36

When does repair begin

Answer 36

24 hours

Question 37

When does graduation tissue appear

Answer 37

3-5 days

Question 38

What mediates angiogenesis

Answer 38

VEGF

Question 39

When is angiogenesis needed

Answer 39

Critical for healing Collateral circulation for ischemic Tumor growth

Question 40

What are the steps for fibrogenesis

Answer 40

Migration and proliferation of fibroblasts | Deposition of ECM

Question 41

What mediates fibrogenesis

Answer 41

TGF-B

Question 42

What does TGF-B do

Answer 42

produce collagen, fibronectin, proteoglycan | Inhibit collagen degradation

Question 43

What happens if you don't have normal collagen synthesis

Answer 43

Wont heal normally

Question 44

What is fibrinous

Answer 44

Containing fibrin | Insoluble protein from fibrinogen

Question 45

What is fibrou

Answer 45

Containing fibroblasts and collagen

Question 46

What is granulation tissue

Answer 46

Early scar | Highly vascular, fibroblasts, loose ECM, inflammatory cells

Question 47

What is a granuloma

Answer 47

Inflammation with epithelioid macrophages

Question 48

What synthesizes remodeling of scar

Answer 48

fibroblasts

Question 49

What synthesizes degradation of scar

Answer 49

metalloproteinases (MMP)

Question 50

Factors that influence tissue repair

Answer 50

``` Infection Nutrition Steroids (anti inflammatory) mechanical variables Poor perfusion Foreign bodies location keloid ```

Question 51

What is the most important factor for tissue repair

Answer 51

infection

Question 52

What nutrient is important for collagen synthesis

Answer 52

Vitamin c

Question 53

What is a keloid

Answer 53

Accumulation of collagen, prominent raised scar

Question 54

3 phases of wound healing

Answer 54

Inflammation Translation tissue formation Contraction of wound, ECM deposition, remodeling