Inflammation, Repair/Regneration, and Thrombosis

Question 1

What are 3 characteristics of acute inflammation?

Answer 1

1. sudden onset
2. short duration
3. usually resolves

Question 2

Example of acute inflammation?

Answer 2

Appendicitis

Question 3

Which cells involved in acute inflammation?

Answer 3

Neutrophil-mediated

Question 4

3 characteristics of chronic inflammation?

Answer 4

1. slow onset or sequel to acute
2. long duration
3. may never resolve

Question 5

Example of chronic inflammation?

Answer 5

Tuberculosis

Question 6

What cells involved in chronic inflammation?

Answer 6

Macrophages and Lymphocytes

Question 7

What is the difference between good and bad inflammation?

Answer 7

good response is to infection or injury, bad response is autoimmunity or over-reaction to stimulus

Question 8

Lifespan of neutrophils?

Answer 8

short, 2-3 days

Question 9

How do neutrophils work?

Answer 9

phagocytosis and have lysosomes that contain bacteria killing enzymes. also release chemicals that attract other inflammatory cells

Question 10

When do neutrophils appear on site of acute inflammation?

Answer 10

first

Question 11

Lifespan of macrohpages and lymphocytes?

Answer 11

longer

Question 12

Function of macrophages?

Answer 12

transport material to lymph nodes (secondary immunity), ingest bacteria

Question 13

Function of lymphocytes?

Answer 13

Produce chemicals to attract other inflammatory cells and have immuniological memory

Question 14

Where are endothelial cells located?

Answer 14

capillary blood vessel lining

Question 15

How do endothelial cells respond to inflammation?

Answer 15

become sticky and porous so inflammatory cells stick and pass into tissues

Question 16

How do endothelial cells respond to damage?

Answer 16

grow into areas to form new vessels

Question 17

What happens to capillary sphincters during inflammation?

Answer 17

Open, causing redness. Arterioles leak and cause swelling

Question 18

What do fibroblasts form?

Answer 18

long lived, collagen in areas of chonic inflammation and repair

Question 19

What are the 5 cardinal signs of inflammation?

Answer 19

1. redness
2. swelling
3. heat
4. pain
5. loss of function

Question 20

What are the 3 stages of inflammation?

Answer 20

1. change in vessel calibre and flow
2. increased vascular permeability and formation of fluid exudate
3. formation of cellular exudate

Question 21

How is cellular exudate formed?

Answer 21

emigration of neutrophil polymorphs into extravascular space

Question 22

What is a granuloma?

Answer 22

Specific type of chronic inflammation with collections of macrophages surrounded by lymphocytes

Question 23

What is resolution (brief)?

Answer 23

Complete restoration

Question 24

What is suppuration?

Answer 24

Formation of pus: mix of living and dead neutrophils, bacteria, cellular debris, and lipid globules

Question 25

What is organisation?

Answer 25

Tissue replacement by granulation

Question 26

Give 5 treatment options for inflammation

Answer 26

1. Ice 2. Antihistamines 3. Ibuprofen (inhibits prostaglandin) 4. Corticosteroids 5. Aspirin

Question 27

What is the definition of resolution?

Answer 27

When initiating tissue factor is removed, tissue is undamaged or able to regenerate

Question 28

Example of resolution in the lungs?

Answer 28

Lobar Pneumonia affects a lobe rather than the whole lung

Question 29

What happens in lobar pneumonia?

Answer 29

Alveoli fill with neutrophil polymorphs instead of air. Pneumocytes that line alveoli can regenerate

Question 30

Why is cirrhosis not an example of resolution?

Answer 30

Forms fibrous tissue between regenerative tissue

Question 31

What is an abrasion?

Answer 31

Superficial skin wound

Question 32

How does an abrasion heal?

Answer 32

scab forms --> epidermis grows from adnexa --> thin confluent epidermis --> final epidermal regrowth

Question 33

What is healing by 1st intention?

Answer 33

An incision where the sides of the wound can meet so healing can be quick

Question 34

What is the process of healing by 1st intention? (5 steps)

Answer 34

Incision --> exudation of fibrinogen --> weak fibrin join --> epidermal regrowth and collagen synthesis --> strong collagen join

Question 35

What is healing by 2nd intention?

Answer 35

Wound margins can't be brought together

Question 36

Stages of healing by 2nd intention? (5 steps)

Answer 36

loss of tissue --> granulation tissue --> organisation --> early fibrous scar --> scar contraction

Question 37

What is organisation?

Answer 37

Specialised tissues repaired by fibrovascular connective tissue - occurs with production of granulation and removal of dead tissue

Question 38

What is granulation tissue?

Answer 38

Loops of capillaries supported by myofibroblasts that contract to reduce wound size

Question 39

What is the definition of repair?

Answer 39

Initiating factor is still present so tissue is damaged and unable to regenerate

Question 40

In repair, what is damaged tissue replaced by?

Answer 40

fibrous tissue made up of collagen, produced by fibroblasts

Question 41

Example of repair?

Answer 41

heart attack after myocardial infarction

Question 42

Which cells can regenerate? (6)

Answer 42

- hepatocytes - pneumocytes - gut epithelium - skin epithelium - osteocytes - all blood cells

Question 43

Which cells can't regenerate? (2)

Answer 43

- mycoardial - neurones

Question 44

Why don't blood clots form all the time? (2 reasons)

Answer 44

Laminar flow - cells travel in centre of vessel Endothelial cells - line vessels and are not sticky when healthy

Question 45

Definition of thrombosis?

Answer 45

Formation of a solid mass from blood constituents in an intact vessel during life

Question 46

What are the stages of a thrombus forming? (4)

Answer 46

1. vascular spasm and endothelial damage exposes collagen 2. platelet aggregation: platelets release chemicals that cause more platelets to stick 3. clotting cascade produces fibrin which entraps RBCs in mesh and forms clot 4. aggregation and cascade are positive feedback loops

Question 47

What are the 3 components of Virchow's triad?

Answer 47

1. change in vessel wall 2. change in blood flow 3. change in blood constituents

Question 48

Example of something that could change vessel walls?

Answer 48

cigarette smoking and vaping

Question 49

Example of that changes blood flow?

Answer 49

stasis - blood flow is slow and not laminar so platelets drag along endothelial cells

Question 50

What inhibits platelet aggregation at a low dose?

Answer 50

aspirin

Question 51

Definition of an embolism?

Answer 51

process of a solid mass in the blood being carried to a place where it gets stuck and blocks vessel

Question 52

What are causes of an emboli other than a thrombus?

Answer 52

air, cholesterol crystals, tumour, amniotic fluid, fat

Question 53

Difference between an arterial and venous embolism?

Answer 53

arterial: systemic, downstream of entry point venous: vena cava --> right side of heart --> pulmonary arteries

Question 54

Why are the lungs a filter for emboli?

Answer 54

the emboli is too big to get into the capillaries

Question 55

Definition of ischaemia?

Answer 55

A reduction in blood flow to a tissue without other implications

Question 56

Definition of infarction?

Answer 56

A reduction in blood flow that causes subsequent death of tissue cells

Question 57

What is infarction usually caused by?

Answer 57

thrombosis of an artery

Question 58

What is end artery supply?

Answer 58

organs supplied by only one main artery, meaning they are more susceptible to infarction

Question 59

Which organs have dual supply so are less susceptible to infarction?

Answer 59

liver, lungs, brain