B2.050 Chronic Complications of Diabetes Mellitus

Question 1

how is it that diabetics are in a proinflammatory state but are also more prone to infection?

Answer 1

the proinflammatory state is due to release of cytokines and a nonspecific rise in inflammation throughout the body
this state reduces the efficacy of first responders to actual infections, leading to the increased risk of infection

Question 2

what is the difference between tissue regeneration and tissue repair?

Answer 2

regeneration has a superior functional outcome- don’t easily in epithelium due to epithelial stem cells, but difficult in infrastructure wounds
repair of tissues usually comes with scarring and structural and functional consequences

Question 3

what are the 3 primary steps to repair by connective tissue deposition

Answer 3

angiogenesis
granulation tissue
remodeling

Question 4

why does angiogenesis produce leaky vessels?

Answer 4

partially by default and the virtue of the formation process- they’re being developed piece by piece so can’t be immediately structurally sound
also allows inflammatory cells easier passage between intra/extracellular compartments

Question 5

what are the components of granulation tissue?

Answer 5

fibroblasts
loose connective tissue
leukocytes
leaky vessels

Question 6

what is remodeling?

Answer 6

reorganization of college and increased cross linking as wound healing progresses

Question 7

why is there contraction in scar remodeling?

Answer 7

1. as collagen cross links, collagen pulls tissue together

2. fibroblasts have contractile properties due to presence of actin (myofibroblasts)

Question 8

what are the 3 components of angiogenesis?

Answer 8

growth factors (VEGF, FGF, angioprotein)
notch signaling
ECM proteins and enzymes

Question 9

what is the function of growth factors in angiogenesis?

Answer 9

migration and proliferation of endothelial cells

Question 10

what is the function of notch signaling?

Answer 10

regulates sprouting and branching of vessels

Question 11

what is the function of ECM proteins and enzymes in angiogenesis?

Answer 11

interact with integrin receptors on endothelial cells

enzymatic remodeling allows growth

Question 12

how is extracellular matrix degradation controlled in remodeling?

Answer 12

matrix metalloproteinases
inactive zymogens, activated by proteases like plasmin
inactivated by tissue inhibitors of metalloproteinases

Question 13

how does wound strength change over time?

Answer 13

increases

Question 14

how does new collagen appear different from old collagen on a slide?

Answer 14

appears lighter due to increased fluid and edema

Question 15

how do the leading edges of benign and malignant neoplasms differ?

Answer 15

malignant- always has young collagen deposits due to constant tissue injury due to invasion and the resulting inflammation in host tissue
benign- capsule of well developed collagen at edge due to lack of invasion

Question 16

characterize healing by first intention

Answer 16

minimizes time of healing
limited connective tissue
limited scarring, but limited strength

Question 17

what is wound dehiscence?

Answer 17

edges of a wound come apart

Question 18

what is ulceration?

Answer 18

wound heal from the bottom up; some may never epithelialize

Question 19

what is fibromatosis?

Answer 19

semiautonomous proliferation of fibroblasts beyond what is required
difficult to control

Question 20

what kinds of factors negatively affect would healing?

Answer 20

infection
nutritional status (vitamin C)
steroids
mechanical factors
poor perfusion
foreign bodies
type and extent of injury
location of injury