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Adult Patient 1 > Tissue Repair > Flashcards

Flashcards in Tissue Repair Deck (37):
1

What is the Parenchyma?

Functional parts of an organ

2

What is the Stroma?

The structural tissue of organs

Connective tissues

3

What are the causes of Tissue Damage? (6)

Trauma
Infection
Physical and Chemical Agents
Tissue Necrosis
Foreign Bodies
Immune Reactions

4

What is Diapedesis?

Passage of blood ells through intact walls of the capillaries

Typically accompanies inflammation

5

What events occur in the Haemostasis Phase?

Platelet Aggregation
Release of Pro-Inflammatory mediators
Diapedesis

6

What events occur in the proliferation phase?

Alterations in cell-cell and cell-matrix interactions
Migration
Cross-talk between MMPs, integrins and cells
Cytokine and growth factor release
ECM production

Re-epithelisation
Angiogenesis
Fibroplasia
ECM deposition

7

What are MMPs?

Matrix metalloproteinases
Group of enzymes responsible for the degradation of most extracellular matrix proteins

8

What is ECM?

Extracellular Matrix

Collection of extracellular molecules secreted by cells that provides structural and biochemical support to the surrounding cells
Regulates movement and growth of cells

9

What event occurs during the Remodelling phase?

Fibroblast to myofibroblast differentiation

Scar Formation
ECM remodelling and degradation
Contraction

10

What are the phases of tissue repair?

Haemostasis
Inflammation
Proliferation
Remodelling

11

What are the fundamentals of inflammation?

Rubor - Redness
Calor - Heat
Dolor - Pain
Tumor - Swelling
Functio laesa - Loss of Function

12

What is a fibroblast?

Type of cell that synthesises the ECM and collagen, the stroma and plays a critical role in wound healing.

Most common cells of connective tissue

13

What is PDGF?

Platelet derived growth factor

14

What is VEGF?

Vascular endothelial growth factor

Angiogenesis

15

What is CXCL5?

Platelet Factor 4

Binds with high affinity to heparin
Neutralises heparin like molecules on endothelium
Inhibit local antithrombin activity to promote coagulation

Strong chemoattractant for neutrophils and fibroblasts

16

What is CCL5?

Chemokine ligand 5

chemotactic for T cells, eosinophils and basophils

17

What is bFGF?

Basic Fibroblast Growth Factor

Angiogenesis

18

What is TGFβ?

Transforming Growth Factor Beta

Cascade causes differentiation, chemotaxis, proliferation, activation of immune cells

19

What is the function of platelets in tissue repair?

What stage are they involved in?

Formation of Platelet Plug

Release pro-inflammatory mediators

Haemostasis Phase

20

What are the stages of Leukocyte Recruitment?

Rolling
Integrin Activation by Chemokines
Stable Adhesion
Migration through Endothelium

21

What is the roll of neutrophils in tissue repair?

Phagocytosis
Recruited within minutes
Respiratory burst
Anti-microbial

Haemostasis/Inflammation phase

22

What is the respiratory burst?

In neutrophils and macrophages

Intracellular bleach (reactive oxygen species) released to kill engulfed bacteria

Green Enzymes - green discharge

23

What is the role of Macrophages in Tissue Repair?

Resident macrophages - alveolar macrophages and kupffer cells (liver)

Monocyte derived macrophages
M1 - inflammatory
M2 - removing debris

Phagocytic

Respiratory burst

Produce Nitric Oxide

24

What is Granulation Tissue?

New connective tissue and microscopic blood vessels hat form on the surfaces of a wound during the healing process.

Typically grows from the base of the wound and is able to fill wounds of any size

25

What does the outcome of the proliferative phase depend on?

Proliferative potential

26

What are Labile cells?

Where are they found?

Continually dividing

Reproduce new stem cells to replace functional cells

GI tract
Epidermis
Mucosal epithelia
Bone Marrow

27

What are Quiescent cells?

Where are they found?

Stem cells that retain the ability to divide

Enter the cell cycle when activated

Hepatocytes
Renal tubular epithelium
Pancreatic acini

28

What are permanent cells?

Where are they found?

Terminally differentiated cells
No proliferative capacity

Damage to these cells leads to scarring

Cardiac myocytes
Brain cells
Neurons
Skeletal muscle
Red blood cells

29

What are the different pathways for angiogenesis? (2)

Mobilisation of EPCs (endothelial progenitor cells) from bone marrow

Angiogenesis from pre-existing vessels

Driven by VEGF

30

What substances make up the Extracellular Matrix?

What is the role of each substance?

Collagen - tensile strength

Elastin - elastic stretch and recoil

Proteoglycans - regulate structure and permeability, moderate cell growth, bind growth factors

Adhesive glycoproteins - fibronectin and laminin - cell recognition, adhesion, migration and proliferation

Integrins - major cell surface receptors, mediating cell adhesion to ECM

31

What types of cels can become myofibroblasts?

Fibrocytes
Resident fibroblasts
Alveolar epithelium

32

What is first intention skin healing?

Focal disruption of the basement membrane and limited loss of epithelial cells

surgical incision

33

What is skin healing by second intention?

Larger injury than first intension

Edges can't be Brough together, due to tissue loss

Results in large scar and contraction

34

What are the local factors that delay tissue repair? (7)

Poor blood supply (atherosclerosis)
Denervation
Infection (and biofilm formation)
Foreign bodies
Mechanical stress
Overwhelming necrosis
Size

35

What are the systemic factors that delay tissue repair? (9)

Anaemia
Nutritional deficiencies (vitC)
Systemic infection
Smoking
Genetic Disorders (marfans)
Diabetes
Malignancy
Haematological abnormalities
Age

36

How, when and where does fibrosis occur?

Excessive deposition of ECM

During abberant wound healing there is too much collagen production

Lung, liver, cardiac, skin, kidney

37

What are complications of skin healing? (3)

Deficient scar: dehiscence, ulceration

Excessive scar: hypertrophic, keloid, proud flesh

Contractures: permanent shortening of a muscle or joint