The Study On Repair Effect Of Curing Burned Surface Of Rabbits With Recombinant Human Epidermal Growth Factor(rh-EGF) Gel And Silver Sulfadiazine Cream

Objective:By self control study method,To observe the effect ofRecombinant human epidermal growth factor (rh-EGF) gel compoundSulfadiazine Silver Cream (SD-Ag) on deep second degree burn woundhealing of rabbits, explore the action mechanism of rh-EGF gel compositeSD-Ag to promote wound healing. Methods:Selected20healthy adult NewZealand white rabbits randomly,2%pentobarbital sodium intravenousanesthesia,8%sodium sulfide back hair removal,Respectively made threecouple3.0cm diameter circular deep Ⅱ degree burn wound on both sidesof the spine in rabbits from front to back of a total of6,the wound space2cm;each rabbit wound along the spine from front to back as A,B,C threegroups,group A:SD-Ag group,group B:rh-EGF gel group,group C:combinedtreatment group,the wound coated2-3mm thick drug,vaseline gauze coverafter sterile dressing,replaced once a day;5rabbits were killed after4D,7D,10D,14D,wound healing observed with naked eye,with a transparentgrid paper delineate each wound graphics and calculate the wound healingrate (WHR);first take the subeschar tissue1g to Subeschar bacterialquantitative,second wound central sampling which were stained with HE to observe,immunohistochemical staining and microvessel density(MVD)andEpidermal Growth Factor Receptor(EGFR).Results:(1)WHR:each woundand gradually reduced with the time prolonging,the wound healing rate ateach time point of combination group were higher than that of simple group,but after scalding in4D the difference was not statistically significant(P>0.05),burn7D,10D,14D,Wound healing rates of group C (combinationgroup) were:34.54±2.69,62.72±11.52,76.16±13.60, but the simplegroup were: group A (SD-Ag):10.96±2.25,23.37±4.16,55.95±9.55;group B (rh-EGF gel):20.89±3.33,51.88±14.53,64.07±6.54,thedifference was statistically significant (P<0.05);(2)HE:after scalding in4D,the residual skin appendages damage of each group were increasedobviously,subcutaneous interstitial infiltration of inflammatory cells.theinflammatory reaction in4and reached the peak at7D,inflammatory cellsmainly located in the epidermis and dermis,partly diffuse full skin eveninvade muscle layer,7D gradually decreased, group A,group C reaction inadvance and decrease rapidly,10D as the island shapehyperplasia,compared group C with group A,group B,a capillary endothelialcells sprouting,the14D of wound epithelization,fibroblast cell numberdecreased,but still more capillary number;(3)Analysis of subeschar bacterialquantitative:scald after4to7D bacterial load began to decrease,most of thebacteria are cleared by body itself in14D,use105cfu/g as baseline tojudge,groups by chi-square test,group A,group C and group B the difference were statistically significant(P<0.05),but group A,group C showed nosignificant difference(P>0.05);(4)The value of MVD:use isolated brownvascular endothelial cells or cell clusters represent a separate microvasculardefinition standard,CD34antibody markers showed MVD,observation ofrandom5field of vison at high magnification,results show that:theexpression of each group increased rapidly in7D and reach the peak at14D,the three groups had statistical significance difference between the datain each period(P<0.05),group B,group C was highly expressed in,groupC(combination group)showed high expression;(5)Average optical density ofEGFR (AOD):each group satisfied the regular that first increased and thendecreased.The expression of EGFR in group B and group C are aheaded andstronger than group A after scalding in7D,10D,group B,group C have nosignificant differences(P>0.05),but Significantly differences with group A(P<0.05),compared group B,group C with group A,the expression of EGFRwas weaker,which may be related to the degree of scar proliferation andprognosis.Conclusion:(1)rh-EGF gel composite SD-Ag application in thewound,can play a good antibacterial and promote cell proliferationsynergistically,than alone therapy effect is obvious.(2)rh-EGF gel compositeSD-Ag joint used in wound healing, can formation a membrane which notonly provide the necessary moist environment but also inhibit theinflammatory infiltration into the wound,have a certain preventive effect oncontrol wound infection.(3)the combined application of rh-EGF gel composite SD-Ag,EGFR expression induced by early,promote epidermalcells and vascular endothelial cells to form,thus accelerating wound healing.