Summary's chapter 3

Question 1

Is inflammation always disadvantageous?

Answer 1

No, it is also a beneficial host response to foreign invaders and necrotic tissue.

Question 2

What is a good memory aid to remember the steps of inflammation?

Answer 2

The 5 Rs:

1. Recognition of the injurious agent
2. recruitment of leukocytes
3. removal of the agent
4. regulation (control) of the response
5. Resolution (repair).

Question 3

What are causes of inflammation?

Answer 3

Infections, tissue necrosis, foreign bodies, trauma and immune responses.

Question 4

What cells can sense the presence of microbes and necrotic cells?

Answer 4

Epithelial cells, tissue macrophages and dendritic cells leukocytes etc.

Question 5

What can be the outcome of acute inflammation?

Answer 5

Elimination of the noxious stimuli followed by decline of the reaction and repair of the damaged tissue or persistent injury resulting in chronic inflammation.

Question 6

Fill in the gap
… (1) is induced by inflammatory mediators such as
histamine, and is the cause of … (2) and
… (3) of blood flow.

Answer 6

1. vasodilation
2. erythema
3. stasis

Question 7

By which mediators is increased vascular permeability induced?

Answer 7

Histamine, kinins and other mediators.

Question 8

What is the result of increased vascular permeability?

Answer 8

It allows plasma proteins and leukocytes, the mediators of host defense, to enter sites of infection or tissue damage. Exudation results in edema.

Question 9

Except vascularisation, what other system is involved in inflammation?

Answer 9

Lymph vessels and nodes, they often show redness and swelling.

Question 10

What cells are recruited from the blood into the extravascular tissue where infectious pathogens or damaged tissues may
be located, migrate to the site of infection or tissue injury, and
are activated to perform their functions?

Answer 10

Leukocytes.

Question 11

Name the steps of leukocyte recruitment.

Answer 11

• Loose attachment to and rolling on endothelium

- Migration through interendothelial gaps.

Question 12

Which cytokines (among others) promote expression of selectins and integrins ligands on endothelium?

Answer 12

TNF, IL-1

Question 13

What kind of proteins increase the activity of integrins for their ligands and also promote directional migration of leukocytes?

Answer 13

Chemokines

Question 14

Which immune cells predominate in early inflammatory infiltrates and by which immune cells are they replaced?

Answer 14

Neutrophils, they get replaced by monocytes and macrophages.

Question 15

How do leukocytes eliminate microbes and dead cells?

Answer 15

By phagocytosis (through destruction in phagolysosomes)

Question 16

By what is destruction of microbes and dead cells caused?

Answer 16

By free radicals (ROS, NO).

Question 17

What is another function of neutrophils?

Answer 17

They can extrude their nuclear contents to form extracellular nets that trap and destroy microbes.

Question 18

What is the physiologic role of inflammation? What is the pathologic consequence of inflammation?

Answer 18

The mechanisms that function to eliminate microbes and dead cells (physiologic role), are also capable of damaging normal tissues (pathologic consequence).

Question 19

What is the function of vasoactive amines (mainly histamine)?

Answer 19

Vasodilation and increased vascular permeability

Question 20

What are metabolites of arachidonic acid?

Answer 20

Leukotrienes and prostaglandins.

Question 21

Where are arachidonic acid metabolites involved in?

Answer 21

Vascular reactions, leukocyte chemotaxis..

Question 22

What are principal cytokines in acute inflammation?

Answer 22

TNF, IL-1 and chemokines.

Question 23

What does complement system activation lead to?

Answer 23

It leads to the generation of multiple breakdown product, which are responsible for leukocyte chemotaxis, opsonization and phagocytosis and cell killing.

Question 24

What is the function of kinins?

Answer 24

They mediate vascular reactions and pain.

Question 25

Fill in the gap:
… (1) is caused by microbes that resist elimination, immune
responses against self and environmental antigens, and some
toxic substances (e.g., silica); underlies many medically important diseases.

Answer 25

1. chronic inflammation

Question 26

What kind of inflammation is morphologically specific for chronic inflammation?

Answer 26

Granulomatous

Question 27

Through which cytokines is fever induced (through stimulation and production of PGs in hypothalamus)?

Answer 27

TNF, IL-1

Question 28

What is leukocytosis?

Answer 28

Cytokines stimulate production of leukocytes from precursors in the bone marrow.

Question 29

Tissues consist of continuously dividing cells, normally quiescent cells that are capable of proliferation and non-dividing cells. The regenerative capacity of a tissue depends on …

Answer 29

the proliferative potential of its constituent cells.

Question 30

What is a classic example of repair by regeneration?

Answer 30

Regeneration of the liver

Question 31

How does repair occur?

Answer 31

By deposition of connective tissue and scar formation if the injured tissue is not capable of regeneration or if the structural framework is damaged and cannot support
regeneration.

Question 32

What are main steps in repair by scarring?

Answer 32

Clot formation, inflammation, angiogenesis and formation of granulation tissue, migration and proliferation of fibroblasts, collagen synthesis,
and connective tissue remodeling

Question 33

What cells are critical for orchestrating the repair process,
by eliminating offending agents and producing cytokines and
growth factors that stimulate the proliferation of the cell types
involved in repair?

Answer 33

Macrophages

Question 34

What are the main phases of cutaneous wound healing?

Answer 34

Inflammation, formation of granulation tissue and ECM remodeling.

Question 35

How can cutaneous wounds heal?

Answer 35

By primary union (first intention) or secondary union (secondary intention).

Question 36

What conditions can alter wound healing?

Answer 36

Infection and diabetes. The type, volume, and location of
the injury are important factors that influence the healing
process.

Question 37

What can cause keloids in the skin?

Answer 37

Excessive production of ECM

Question 38

What leads to tissue fibrosis?

Answer 38

Persistent stimulation of collagen synthesis in chronic inflammation