Parks Cell injury repair and wound healing

Question 1

What are the phases of cutaneous wound healing?

Answer 1

injury-> coagulation-> early inflammation (neutrophils)-> late inflammation (macrophages)-> proliferation-> remodeling

Question 2

Whats the first thing you need to do to a wound and what does this?

Answer 2

clean it up, macrophages

Question 3

There are 2 ways a tissue can repair itself. The most common way is (blank) . But, tissues like the superficial epidermis and liver can regenerate their cells to heal almost to normal.

Answer 3

scarring

Question 4

When you get a corneal abrasion, stem cells come and heal it right up, what kind of healing is this?

Answer 4

regeneration

Question 5

What contains the corneal stem cells?

Answer 5

the limbus

Question 6

Crypt cells in your colon are (blank)

Answer 6

stem cells

Question 7

Where do embryonic stem cells come from and what are they?

Answer 7

blastocysts

pluripotent

Question 8

The faster you treat a patient, the less liquifactive necrosis and the greater possibility of (blank)

Answer 8

regeneration

Question 9

If you have persistant tissue damage what will happen?

Answer 9

scarring/fibrosis

Question 10

Liver, superificial skin wounds, pneumonia all undergo what kind of healing?

Answer 10

regeneration

Question 11

MI and deep excisional wound undergo what kind of healing?

Answer 11

scar formation

Question 12

Can cardiac myocytes regenerate?

Answer 12

nope, so they heal by scarring

Question 13

scarring is made up of what?

does it contract

Answer 13

collagen

no (which is why heart failure happens, you cant stretch your heart for pumping)

Question 14

What are nondividing permanent cells (terminally differentiated cells)?

Answer 14

cant make them go into cell cycle

like neurons, cardiacmyocytes

Question 15

What are continuously cycling cells (labile cells)?

Answer 15

cells that continously cycle (superficial skin cells, oral cavity, GI tract)

Question 16

What are stable cells?

Answer 16

cells that divide only when needed like hepatocytse

Question 17

How do you kick cells into the cell cycle?

Answer 17

growth factors

Question 18

What does VEGF do?

Answer 18

stimulate proliferation of endothelial cells; increases vascular permeability

Question 19

What does EGF do?

Answer 19

mitogenic for keratinocytes and fibroblasts; stimulates keratinocyte migration; stimulates formation of granulation tissue
(hits up parenchymal cells)

Question 20

What does TGF do?

Answer 20

chemotactic for leukocytes and fibroblasts; stimulates ECM protein synthesis; suppresses acute inflammation
( makes fibroblasts, collagen and ECM)

Question 21

(blank) is one of the main fibrogenic factors and what does it do?

Answer 21

TGF beta

stimulates fibroblasts to produce Type III collagen (this gets replaced w/ type I later)

Question 22

What can macrophages, platelets, and epidermal squamos cells produce?

Answer 22

TGF

Question 23

Why are clots important for healing?

Answer 23

because it contains macrophages, platelets, fibrin. and gives you growth factors to heal

Question 24

How do you coordinate the signals from the growth factors with signals from the ECM?

Answer 24

via integrins, which elicit cross talk

Question 25

What helps to coordinate proliferation, remodeling and apoptosis?

Answer 25

integrins

Question 26

How do you want a wound to look?

Answer 26

red with granulation tissue (indicating you have blood vessels) and dry

Question 27

How do we stimulate angiogenesis?

Answer 27

VEGF-> stimulates residual endothelium to sprout new vessels and recruit pericytes to form new vessels

Question 28

In angiogenesis from (blank), endothelial cells from these vessels become motile and proliferate to form capillary sprouts. Regardless of the initiating mechanism, vessel maturation (stabilization) involves the recruitment of pericytes and smooth muscles cells to form the periendothelial layer.

Answer 28

preexisting vessels

Question 29

Where do you get the endothelial precursor cells (EPCs) ?

Answer 29

from bone marrow

Question 30

(blank) are mobilized from the bone marrow and may migrate to a site of injury or tumor growth. At these sites, (blank) differentiate and form a mature network by linking to existing vessels.

Answer 30

EPCs | EPCs

Question 31

So what are the 2 ways to get angiogenesis

Answer 31

from preexisting vessels | from mobilization of EPCs from the bone marrow

Question 32

What is this tissue: | vascular, edematous, weak and red

Answer 32

granulation tissue

Question 33

You want your wound to get red, so what should you put on them?

Answer 33

hydrogen peroxide

Question 34

What does your body do to your granulation?

Answer 34

turns it into scar tissue (this is why your scars on your arm goes from red to white)

Question 35

When you break your bones what happens?

Answer 35

you get a hematoma get granulation tissue (get some blood vessels) get remodeled

Question 36

When you hear ECM what should your mind be thinking?

Answer 36

fibroblasts (cuz they make collagen)

Question 37

What is re-epithelization? | How do we do this?

Answer 37

re-growth of the epidermis | EGF

Question 38

What is special about the basilar epidermis?

Answer 38

they have skin stem cells

Question 39

What is the first intention of healing?

Answer 39

when you approx. the skin edges together so that it heals better

Question 40

What is second intention of healing?

Answer 40

allow the wound to granulate (open wound)

Question 41

Wound healing is affected by (blank)

Answer 41

``` many factors: meds blood supply nutrition size/shape of wound diabetes infection foreign material degree of immobilization ```

Question 42

Do steroids help with wound healing or hurt wound healing?

Answer 42

HURT IT!

Question 43

(blank) is an area of irregular fibrous tissue formed at the site of a scar or injury. Is it painful?

Answer 43

keloid | no, it just is cosmetically annoying

Question 44

What is the first thing you do with a wound?

Answer 44

immobilize it!

Question 45

How does your heart heal after a heart attack?

Answer 45

days 1-3: neutrophils are trafficked to the infarcted area days 3-7 macrophages come and soften area days7-10: early granulation tissue which peaks around 14 days and begins being replaced by fibrosis/scarring scarring becomes dense and complete in 2 months or greater

Question 46

How come within 4 to 7 days of having an MI, the area of the heart is very soft and fragile?

Answer 46

because there are no myocytes and only macrophages. Which can result in rupture and thus cardiac tamponade

Question 47

What is this: | compression of the heart by an accumulation of fluid in the pericardial sac.

Answer 47

tamponade

Question 48

What can myocardial softening do to the papillary muscles? | What would this result in?

Answer 48

Breakage of them probably dysfunction of the attached mitral heart valve which would result in regurgitation of blood which can lead to heart failure because of inefficient pumping of blood

Question 49

Why does the patient die in cardiac tamponade?

Answer 49

pericardium fills up and squeezes the heart so it cannot pump and then the patient dies of shock

Question 50

What are the four endogenous sources of cardiomyocytes?

Answer 50

cardiomyocyte replication niches of cardiac stem or progenitor cells bone marrow-derived cardiac stem or progenitor cells epicardially derived cardiomyocytes

Question 51

What are the three exogenous sources of cardiomyocytes?

Answer 51

embryonic stem cells induced pluripotent stem cells mesenchymal progenitor cells

Question 52

When you have cardiac failure or something that ruins your myocytes, how do you heal this and why is this a problem?

Answer 52

you heal this via scarring and fibroblasts, which means you have a lot of collagen and reduced contraction