Repair, Regeneration, and Fibrosis (part1)

Question 1

what are soluble signals

Answer 1

cytokines

Question 2

although new collagen formation during repair is essential for restoring strength at the healing site, ______ is a major complication of diseases that involve chronic injury

Answer 2

EXCESS FIBROSIS

Question 3

____ is central to both repair and regeneration

Answer 3

ECM

Question 4

in the adult, successful healing is usually accomplished through…..

Answer 4

collagen deposition or scarring (fibrosis)

Question 5

define healing

Answer 5

reparative tissue response to a wound, inflammation, or necrosis

Question 6

define regeneration

Answer 6

the growth of cells to replace tissues. replacement of lost structures

Question 7

name the 4 basic processes of healing

Answer 7

1. cellular migration
2. inflammation
3. ECM organization and remodeling
4. cell proliferation

Question 8

what are the cell’s “muscles”

Answer 8

actin cytoskeleton

Question 9

what are the cell’s “rails”

Answer 9

extracellular matrix

Question 10

in cell migration, what is involved with signaling

Answer 10

chemokines

Question 11

what is produced as a result of cytoskeleton changes in response to chemokines?

Answer 11

lamellipodium and filipodium

filipodium contains specific CAM that interacts with fibrin/collagen

Question 12

injury causes what 2 things to secrete mediators

Answer 12

mast cells and platelets

Question 13

what releases PDFG

Answer 13

activated platelets

PDFG = platelet derived growth factor

Question 14

mast cells are ______ derived cells that reside in ____ near small blood vessels

Answer 14

mast cells are BONE MARROW derived cells that reside in connective tissue near small blood vessels

Question 15

resident antigen presenting cells that regulate innate and adaptive immunity

Answer 15

dendritic cells

Question 16

____________ are the major population of T cells in the skin

Answer 16

dendritic epidermal T cells

Question 17

true or false

CD4 and CD8 t cells do not play critical roles in normal healing, but DETC’s do

Answer 17

TRUE

Question 18

what is the function of the provisional matrix

Answer 18

temporary to stop blood/fluid loss

Question 19

name 4 components of the provisional matrix and where they’re derived from

Answer 19

plasma-derived proteins - fibrinogen and fibronectin

tissue derived (local) = hyaluron and fibronectin

Question 20

most prominent growth factor in platelet clot

Answer 20

PDGF (platelet derived growth factor)

Question 21

what matrix is also called interstitium

Answer 21

stromal matrix

Question 22

what is the major composiiton of stromal matrix

Answer 22

contains collagen fibers and cells that synthesize collagen

Question 23

name 3 types of fibril forming collagen and 1 type of network forming collagen

Answer 23

fibril forming - 1-3

network forming = type 4 (basement membrane - most important)

Question 24

when collagen is depositied in a serous membrane, what happens

Answer 24

links the parietal and visceral layers and negatively affects function

Question 25

name 3 noncollagenous matrix constituents of the stromal matrix

Answer 25

fibronectin (also part of provisional)
elastin
versican

Question 26

fibronectin, elastin, and versican are all part of the stromal matrix

which is a dimeric protein

Answer 26

fibronectin

Question 27

fibronectin, elastin, and versican are all part of the stromal matrix

which provides viscosity

Answer 27

versican – contains hyaluronic binding proteoglycans

Question 28

the deposition of collagen in a tissue provides what?

Answer 28

strength to the wound/tissue

Question 29

true or false

there is a constant collagen remodeling process

Answer 29

TRUE

accomplished by the action of collagenase provided by fibroblasts

Question 30

source of collagenase

Answer 30

fibroblasts

Question 31

_____ is the long lasting phase of repair

Answer 31

remodeling

Question 32

name the main REMODELING ENZYMES

Answer 32

MMPs (metalloendopeptidases)

Question 33

cell proliferation and migration initiate and promote the formation of………….

Answer 33

GRANLUATION TISSUE

Question 34

Cell activities in healing wounds are largely initiated by _____ receptor systems:

Answer 34

3:

-G-protein coupled receptors activated by chemokines and other factors

-integrin receptors for ECM

-protein tyrosine kinase receptors

Question 35

true or false

platelets are not cells

Answer 35

true

Question 36

THROMBUS FORMATION:

at the site of injury, fibrin binds to fibronectin and is cross linked by…..

Answer 36

factor 13 (transglutaminase 1)

Question 37

excess transglutaminase may cause…..

Answer 37

scarring

Question 38

growth factors control the _______ of cells in wound healing

Answer 38

MIGRATION

Question 39

what is the thing that platelets secrete that is important for platelet aggregation and has pro inflammatory action

Answer 39

thromboxane A2

stimulates activation of new platelets and increases platelet aggregation

Question 40

what is contained in the dense granules of platelets

Answer 40

serotonin, calcium, and ADP

Question 41

what is contained in the alpha granules of platelets

Answer 41

cationic proteins
fibrinogen and coagulation proteins
PDGF

Question 42

is thromboxane A2 a vasoconstrictor or vasodilator

Answer 42

vasoconstrictor

Question 43

what receptor do platelets express? what does it bind to?

Answer 43

GPIb that bonds to collagen (VON WILLEBRAND FACTOR) and GP IIB/IIA that binds to fibrinogen