Wound Healing and Inflammation + MISC Stuff Flashcards
Difference between tissue-resident and monocyte derived macrophages?
Tissue -> early in embryogenesis, erly sorce of proinflammatory cytokines
Monocyte -> differentiate in tissue and reside in ECM (main cell), monocytes promote vascular regrowth
Difference between M1 and M2 cells?
M1:
-activated by infectious agents or proinflmmatory cytokines (IFN-gamma/TNF-alpha)
-debride via phagocytosis
-produces proinflammatory cytokines and PG
M2:
- activated by antiinflammatory cytokines (IL-4, IL-13, IL-10)
- aids n wound repair -> secretes GFs + fibroblasts to produce collagen
Both M1 and M2 secrete collagenase/elastase)
What does it mean to have loci considered “in linkage?”
If genetic distance between marker allele and mutation small enough that mutation is transmitted with trait between generations
What type of wound is best w/bioscaffold & synthetic matrix?
Chronic indolent wound
-acts as comp. substrates for MMP, collagenase
-allows proliferation of ECM
What are some main changes in metabolism of burns?
- Initially hypometabolism “ebb phase”
-basal energy, expenditure during flow phase increases >100% compared to pre-burn - post-burn adipose-> 1/ of energy requirement, protein catabolism 30%
-“Burn diabetes” -> glucose uptake increased from gluconeogenesis and insulin resistance
anerobic glycolysis very high in endothelium and fibroblasts!!
What % of mesencyhmal cells given systemical injection sucessfully home and migrate to site of injury?
What product should be added to it to improve local effect?
<5%
PRP of fibrin gel
For radio, CO2 laser, monopolar cautery char penetrates skin peripheral to skin edge ____mm?
Radio: 0.17mm
CO2: 0.215
Monopolar: 0.255
(For PRP) When does platelet release alpha graules stores & how much is released within 1 hour?
within 10 min
95% is eleased within an hour so give the PRP quickly!
What does each of the following code for?
mRNA
rRNA
tRNA
Small nuclear RNA
Small nucleolar RNA
mRNA - protein sequences
rRNA-mitochondrial ribosomal subunits for translation
tRNA - AA binding sites
Small nuclear RNA - units of spliceosomes
Small nucleolar RNA -molecules in RNA modification
What are advantages and disadvantages of retroviral useage?
Adv: nonimmunogenic, integrate with host genome for long-term expression
Disadv: target cell must be dividing before retrovirus integrates, site of integration random, can cause deleterious effects
Define:
point mutation
missense mutation
nonsense mutation
synonymous mutation
frame shift mutation
microsatellites
point mutation: chnge sequence or length, non-synonymous
missense mutation: change to AA codon -> alter protein structure
nonsense mutation: replace AA codon with stop codon/ends protein sequence
synonymous mutation: changes genetic sequence but still codes for right AA/protein not changed
frame shift mutation: Add or deletes single/multiple base pairs so all are shifted by #
microsatellites: -6 base pair motifs repeated # of times
Know equations of RER (2)
Know protein maintenence loads dog/cats
RER=30BW(kg) +70 or 70(BW(kg))^0.75
How is autologous conditioned sera (IRAP) made?
- Whole blood -> inject into chanber with borosilicate beads
- Coagulates, incubate it at 98.6F for 6-24 hour
- Leukocytes adhere to the beads and it induces signalling & expression of IL-1Ra
- Centrifuge it to isolate the serum and then give it IA
What is difference in collagen prevalence with unwounded vs wounded dermis?
Unwounded: 80% Type 1 / 20% type III
Wounded: Mainly III
What 2 main factors are present in collagen synthesis & what are their functions?
TGF-B
- synthesis T1 collagen
- decrease production of MMPs
-increase production MMP inhibitors
IL-10 (weeks later)
-limits fibroblast recruitment
-decreases production of interferons and PF4
When does granulation tissue appear?
~7 days
With moist wound healing, what dressings would be appropriate for:
Dry
Mild to moderate
heavily exudative
Dry:
water based hydrogel
Mild to moderate:
hydrocolloid sheet, polyurethane foam, maltodexterin polymer flakes (all form gel layer)
heavily exudative:
Ca alginate
If infected hypertonic gauze
Describe major changes in pulmonary system with burns
CO-> decreased O2 carrying capacity, decreased delivery
HCN-> prevents cell respiration
HCl -> irritating to resp. mm, laryngospasm, bronchospasm
Increased pulm vascular permeability and vasoconstriction
atelectasis, deactivation of surfactant
cytokines etc-> apoptosis too from GI endotoxin
What height do dog ears typically regress?
What are techniques to resolve?
<8mm
apex cutaneous suture
horizontal oblique
excise triangles, fusiform, arrowhead, “fudging”
central removal
end removal
rule of halves
Translation goes in which direction?
What are the stop codons?
5’->3’
UAA, UAG, UGA
- When does fibroblast migration occur?
- What factor synthesizes definitive ECM?
- What type of procollagen is formed?
- What cytokines stimulate fibroblasts to migrate?
- 3-5 days post wounding
- Fibroblast growth factor
- Type I and III
- PDGF, TGF-B, and epidermal GF from platelets and macrophages
NB: FGF has many functions but it increases production of fibroblasts, not necessarily their migration
What are the main functions of nitric oxide?
-regulate vascular tone
-produce vasodilation and relaxation
-antagoize vasoconstriction effect of angiotensin II, ROS
-decrease platelet aggregation and leukocyte adesion
-anti-inflammatory effects on GI
-increase production of pro-inflamm cytokines
-induces TH-1 at low concntrations and inhibits them at high concentrations
Which IL-1 is proinflammatory?
Which is Anti?
IL-1Ra -> anti
IL-1B -> Pro
How do chemokines work?
Example?
How are they categorized?
Attraction of cells accross concentration gradient during embryonic development, wound healing, angiogenesis, and inflammatory responses
They are categorized by cyteine residues (e.g. IL-8 = CXCL8)
What are the primary functions of macrophages in wound healing?
- Cytokines IL-1/6/8, TNF-alpha, FGF, EGF, TGF-beta, PDGF
- induce neutrophil apaotosis at 48-96hr
-release metalloprotinases MMP 1/2/3/9 whih degrade ECM to help cells move accross wound
Neutrophil migration and adherence is primarily promoted by which cytokines/mediators?
What other factor amplifies chemotaxis and (+) macrophage, keratinocyte and fibroblast expression?
- PDGF, IL-1, TGF-beta, c3a/c5a, LTB4
-TNF-alpha
Where does platelet-activating factor come from?
Functions?
From phospholipase A2
-Stimulates arachidonic acid release and increases eicosanoids
-increases affinity of surface integrins to enhance adhesion
- platelet aggregation and degranulation
- increased vascular permeability
-bronchoconstriction
What are the main effects of ROS?
-Antibacterial defense, wound debridement, cell signalling, pathologic tissue (??word)
- Homeostasis - generates ATP via respiratory burst / burst helpful to defend from bacterial invaders
- pathologic -> from frustrated phagocytosis that releases damaging agents into extracellular space -> produces ischemia-> ROS
What are examples of positive acute phase proteins?
Negative?
Positive: serum amyloid P, complement protein, coag factors, CRP, Serum amyloid A, kallekrein
Negative: albumin, transferrin, apolipoprotein a
Eicosanoids - what is the precursor?
Made from what via which enzyme?
Cell membrane phospholipids-> via phospholipase A -> arachidonic acid (precursor)
AA-> prostaglandins (via COX) and leukotrienes (via LOX)
Bladder gets 100% of strength within ___ days?
Collagen synthesis normal after ___ days?
Re-epithelializes in ___ days?
21 days
70 days
2-4 days
What are all of the factors released by or stimulated to be released by platelets?
PDGF
TGF-beta
IGF-1
EGF
fibronectin
fibrinogen
thrombospondin
vWF
Factor 8
Name the functions of neutrophils and the cytokines produced
phagocytosis
release superoxide radicals
form neutrophil traps
secrete MMPs
produce cytokines (IL-1/1a/1b/6, TNF-alpha)
What is the most significant PRR (pattern recognition receptor) and what cytokine does it influence?
Toll-like receptors (TLR)
NFkappa-beta causes the leukocyte to release cytokines
Negative pressure wound therapy:
1. What are the size of pores in foam?
2. Standard pressure?
3. What pressure for gauze?
4. Pressure for less-dense tissues?
5. Pressure over grafts?
400-600um pores
-125mmHg standard
-80 for gauze
-75-100 for less dense tissue
-65-75 for grafts
Golden period is how long it takes bacteria to reach ___#s?
10^5 per gram of tissue or mL of exudate
Give the main examples of:
vasoactive amines
pro-inflammatory cytokines
anti-inflammatory cytokines
Vasoactive- histamine, serotonin
pro-inflam-> TNF, IL-1, IL-6, Chemokines (IL-8)
Anti-inflam -> IL-10
Where are kininogens formed?
What are kinins?
What is seen on coags if kinin deficiency?
Formed in liver then circulate
they are vasodilatory proteins
prolonged APTT w/normal coag factors