Comparative study on the repairing effect of stamp skin and meek skin on wounds in patients with extensive burns / 中国医师杂志

Objective:To explore the difference in the therapeutic effect of stamp skin and meek skin on wound repair in patients with extensive burns.Methods:A total of 81 patients with extensive burn from March 2016 to February 2018 in 73th Army Hospital of PLA were selected and divided into group A (stamp skin grafting, 35 cases) and group B (meek skin grafting, 46 cases) according to the choice of wound repair methods before operation. The survival and healing conditions, treatment costs, mortality and rehabilitation of the two groups were compared.Results:There was no significant difference in the survival rate, wound healing rate and mortality between group A and group B (82.86% vs 86.96%, 5.71% vs 8.70%, P>0.05). The survival rate of skin graft in group A was higher than that in group B, and the wound healing time and treatment cost of 1% total body surface area (TBSA) in group A were lower than those in group B [(76.3±5.1)% vs (67.9±6.2)%, (41.5±4.9)d vs (45.8±5.1)d, (1 215.6±235.1)yuan vs (7 689.5±681.0)yuan, P<0.05]. The excellent and good rate of rehabilitation in group A was significantly lower than that in group B (68.57% vs 86.96%, P<0.05). Conclusions:The application of the stamp skin in the repair of wounds in large-area burn patients has a higher flap survival rate than meek skin repair, which can shorten the healing time of the flap and reduce the treatment cost, but the rehabilitation effect is poor.

Cloning of UL7 protein of HSV-1 and analysis of the expression of UL7 protein during the prolifera-tion of HSV-1 / 中华微生物学和免疫学杂志

Objective To express and purify the recombinant UL7 protein of herpes simplex virus 1 (HSV-1), to prepare the corresponding UL7-specific polyclonal antibody and to preliminarily analyze the expression of UL7 protein during the proliferation of HSV-1. Methods The UL7 gene was amplified by PCR and then cloned into the pGEX-5X-1 vector for expression of UL7 protein in the prokaryotic expression system. The constructed expression plasmid, pGEX-5X-1-UL7, was transformed into E. coli BL21 (DE3) to induce the expression of UL7 protein by IPTG. The purified GST-UL7 fusion protein was used as antigen to inject the ICR mouse for the preparation of polyclonal antibody specific for UL7 protein. The titer and speci-ficity of the polyclonal antibody were analyzed by using indirect ELISA and Western blot assay, respectively. The UL7 protein-specific polyclonal antibody was used to detect the expression of UL7 protein at different time points after infecting Vero cells with HSV-1. Results The GST-UL7 fusion protein was efficiently ex-pressed in E. coli BL21 (DE3). The UL7 protein-specific polyclonal antibody was prepared with high titer (1 ∶ 105) and high specificity as indicated by the indirect ELISA and Western blot assay. The expression of UL7 protein was detected at different time points after infecting Vero cells with HSV-1. Conclusion The GST-UL7 fusion protein was obtained successfully and the UL7 protein-specific polyclonal antibody was pre-pared. Accompany with the proliferation of HSV-1, the expression of UL7 protein was detected at different time points by using the polyclonal antibody.

Application of damage control surgery in treatment of severe electric burn / 实用医学杂志

Objective To explore the effect of damage control surgery (DCS) in the treatment of severe electric burn. Methods Retrospective analysis on clinical data of 45 patients with severe electric burn was con-ducted. According to implementing DCS or not , patients were separated into DCS group and control group. In DCS group, tangential excision and transplanted xenogenic acellular dermal matrix was conducted for severe electric burn cases with deep Ⅱ degree wound, and escharectomy and VSD dressing for Ⅲ~Ⅳ degree electric contact burn wound at the first stage then skin-grafting or skin flap-grafting on the secong stage was applied. For control group , debridement, tangential excision or escharectomy and skin-grafting or skin flap-grafting to close the wound were conducted. We compared the difference in terms of operation time, length of stay, disability rate, mortality and complications between 2 groups. Results The operation time, incidince of disability and complications in DCS Group obviously decreased but there was no difference in length of stay and mortality in both groups. Conclusion DCS is effective for reducing complications and optimizing therapeutic effect for severe electric burn patients.

Mechanisms and effects of biosynthesis and apoptosis in repair of full-thickness skin defect with collagen-chitosan dermal stent / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate biosynthetic and apoptotic mechanisms in repair of full thickness skin defect with collagen-chitosan porous scaffold transplantation, and to determinate differences between wound repair with the scaffold transplantation and scar healing without the scaffold transplantation.</p><p><b>METHODS</b>The full thickness skin defects were made on 10 Bama miniature pigs and the bilayer dermal equivalent (BDE) composed of collagen-chitosan porous scaffold and silicone membrane was transplanted on wounds. Surfaces of wounds were observed at 1, 2, and 3 weeks after the BDE transplantation, and so were done the wound repairs after epidermis had been grafted for 2 weeks on surface of the scaffold which had been transplanted on skin defect wounds for 2 weeks. At the same time, TGF-beta1 expressions, apoptosis and self collagen replacement of scaffolds in wounds were detected in situ by immunohistochemical staining, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) and picrosirius red polarized light. Wounds without scaffold transplantation were studied as control.</p><p><b>RESULTS</b>1) Wounds with the scaffold transplantation were different from granulation tissue. 2) The peak of TGF-beta1 expression in the scaffold wounds was from 1 to 2 weeks after BDE transplantation, and TGF-beta1 expressions decreased continuously from 3 to 4 weeks. TGF-beta1 expressions increased continuously in the control wounds from 1 to 3 weeks and decreased on 4 weeks. TGF-beta1 expressions in the scaffold wounds on 1st and 2nd week were significantly higher than those in the corresponding control wounds, whereas, TGF-beta1 expressions in the scaffold wounds on 3rd and 4th week were significantly lower than those in the corresponding control wounds. 3) Apoptosis increased continuously in the scaffold wounds from 2 to 4 weeks after BDE transplantation, and so did in the control wounds from 3 to 4 weeks. However, apoptosis signals in the scaffold wounds on 2nd, 3rd, and 4th week after BDE transplantation were significantly more than those in the corresponding control wounds, and there was no difference between apoptosis signals in the scaffold wounds on 1st week after BDE transplantation and those in the corresponding control wounds. 4) Observation by picrosirius red polarized light method: self collagen began to synthesize in the scaffold wounds on 1st week after BDE transplantation, and scaffolds had been replaced by self collagen from 2 to 3 weeks after BDE transplantation.</p><p><b>CONCLUSIONS</b>Collagen-chitosan porous scaffold plays a very important role in wound healing of full thickness skin defect. The mechanisms of wound repair by dermal scaffold are different from those by granulation and scar healing. It has a good future in repairing skin defect.</p>

Study on repair of full-thickness skin defect with collagen-chitosan dermal stent in pigs / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate angiogenesis of collagen-chitosan porous scaffold, and to study survive of skin grafts on the scaffold after bilayer dermal equivalent (BDE) was transplanted on wounds with full thickness skin defects.</p><p><b>METHODS</b>The full thickness skin defects were made on 10 Bama miniature pigs and the BDE composed of collagen-chitosan porous scaffold and silicone membrane was transplanted on wound. Angiogenesis in dermal equivalent, wound healing, and healing and survive of skin grafts on dermal equivalent were observed in 1, 2, and 3 weeks after the BDE transplantation. At the same time, CD34 positive signals (neo-forming micro-vessels) were detected by immunohistochemical staining.</p><p><b>RESULTS</b>Inflammatory cells and fibroblasts infiltrated into dermal equivalent and a few new micro-vessels had been formed in 1 week after the BDE transplantation; neo-forming micro-vessels perpendicular to wound bed had increased significantly in 2 weeks after the BDE transplantation; neo-forming micro-vessels could be observed in almost all dermal equivalents in 3 weeks after the BDE transplantation. CD34 positive signals (neo-forming micro-vessels) in 3 weeks after the BDE transplantation was much more than those in 2 weeks after the BDE transplantation, and CD34 positive signals in 2 weeks after the BDE transplantation was much more than those in 1 week after the BDE transplantation. Survival rate of intermediate split thickness skin graft were 10%, 70% and 100% respectively after the skin grafts had been grafted for 2 weeks on surface of the scaffold which had been transplanted for 1, 2 and 3 weeks. Epidermis which had been grafted on surface of the scaffold for 1 or 2 weeks could perfectly survive after BDE had been transplanted for 1 or 2 weeks.</p><p><b>CONCLUSIONS</b>Collagen-chitosan porous scaffold plays a very important role in wound healing of full thickness skin defect and can induce fibroblast infiltration and new micro-vessel formation. Epidermis grafted on surface of collagen-chitosan porous scaffold can perfectly repair wounds, and it has brilliant applied prospects in repairing skin defect.</p>

Skin-like structure generated from implantation of hair follicle bulb cells into collagen/chitosan porous scaffolds in vitro / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To observe the skin regeneration after hair follicle bulb cells were implanted into collagen/chitosan porous scaffolds in vitro.</p><p><b>METHODS</b>The cultured dorsal hair follicle bulb cells of 4d-old C57BL/6J mice were implanted into collagen/chitosan porous scaffolds in vitro. The skin regeneration was observed.</p><p><b>RESULT</b>The skin-like structure was formed on the collagen/chitosan porous scaffolds where were cultured the hair follicle bulb cells before 4th passages.</p><p><b>CONCLUSION</b>The skin-like structure is generated in vitro when early passages of cultured hair bulb cells are implanted into collagen/chitosan porous scaffolds.</p>

Study on the interface of human hepatocyte L-02 polypropylene:simple culture method of human hepatocyte with spheroidal aggregate culture / 中华外科杂志

<p><b>OBJECTIVE</b>To found new interface of human hepatocyte/poly propylene with good cytocompatibility for made polypropylene hollow fibers bioreactor of bioartificial liver in future.</p><p><b>METHODS</b>Using the macromolecular hydroperoxide groups on the polypropylene membrane surface as initiators, acrylamides were polymerized on the polypropylene membranes, under induction by both UV irradiation and Fe2+ reduction. Growth characteristics of human hepatocyte L-02 were detected when it was cultured on polystyrene, polypropylene and modified polypropylene membrane surface.</p><p><b>RESULTS</b>Water contact angle measurement of the polypropylene and the modified polypropylene membranes decreased from (72 +/- 5) degrees to (30 +/- 4) degrees , which indicated that the hydrophilicity of the membrane was improved obviously after the grafting modification. Human hepatocyte L-02 could not adhere and spread on modified polypropylene membrane surface, and grown in spheroidal aggregate with higher density and higher proliferation ratio measured by MTT method.</p><p><b>CONCLUSIONS</b>Acrylamide polymerized on the polypropylene membranes is a good method which not only improved human hepatocytes cytocompatibility but also found a new simple culture method with spheroidal aggregate culture of human hepatocyte.</p>