Oxygen Penetration Through Full-Thickness Skin by Oxygen-Releasing Sutures for Skin Graft Transplantation

The transplantation of full-thickness skin grafts(FTSGs)is important for reconstructing skin barrier and promoting wound healing.Sufficient oxygen supply is closely related to the success of skin grafting.However,full-thickness oxygen delivery is limited by the poor oxygen permeability of skin.Oxygen-releasing sutures(O_(2)sutures)were developed to facilitate oxygen penetration through full-thickness skin.The O_(2)sutures delivered 100 times more oxygen than topical gaseous oxygen therapy at a 15 mm depth in the skin model.Under extreme hypoxia(<0.5%O_(2),v/v),O_(2)sutures could also promote endothelial cell proliferation.After the transplantation of FTSGs in mice,O_(2)sutures accelerated blood re-perfusion and increased the survival area of the skin graft.It is expected that O_(2)sutures will be adopted in clinical applications to increase the success rate of full-thickness skin transplantation.

Study on Different Types of Skin Flap Transplantation to Repair Forefoot Damaged Injury

Objective To investigate the clinical effect of different types of skin flap transplantation in repairing forefoot lesion.Methods From January 2016 to June 2019,62 patients with forefoot damage were selected and their clinical data were retrospectively analyzed.All the selected patients received skin flap transplantation and repair,of which 26 patients received free myocutaneous flap transplantation and repair,and were treated as group A.The other 36 patients underwent retrograde foot flap transplantation and repair.They were taken as group B,and the clinical treatment methods and curative effects were summarized.Results Among the 26 patients in group A,the skin flaps of 21 patients survived completely,while those of the other 5 patients showed partial necrosis at the edge of the skin flaps.They were treated with free skin grafting and healed after regular dressing change.All the skin flaps survived.Follow-up for at least 6 months showed that 11 patients had mild claudication and skin flap sensation was slightly poor.Among the 36 patients in group B,only 2 cases suffered from distal partial necrosis after the operation,which was caused by large tension after dorsum pedis flap transplantation.After systematic treatment and regular dressing change by doctors,the flaps of 2 patients healed.In addition,venous reflux disorder occurred in 3 patients with medial saphenous nerve nutrient vessel flap of the foot,which was related to swelling factors.The flaps of other patients survived,healed well and did not show infection symptoms.Conclusion According to the actual condition of patients with forefoot damage,the flap repair method is formulated,which has good short-term and long-term therapeutic effects and plays an important role in repairing forefoot damage.

Place of Total Self-Skin Transplant in the Management of Burns in Children: Results and Predictive Factors

Introduction: Skin transplant is essential in the management of skin substance losses, especially in deep burns. Our work aims to present, through a series of cases, the results of the skin self-transplant carried out to supplement the treatment of skin burns. Materials and Methods: A one-year prospective study of the total self-skin transplant performed in the management of burns in children was included. After clinic and biologic considerations, a total self-skin transplant was performed. Results: Forty-five burns were hospitalized, of which six patients received a total self-skin transplant. The average age was 7.43 years with male predominance. The burns were deep thermal burns, preferentially located on the trunk and upper limbs covering over 10% - 25% of the body surface of which 3% - 13% was transplanted. Transplant held in all patients. The surfaces left in spontaneous healing took at least 6 months to heal with some complications. Discussion: We performed a total self-skin transplant beyond technical reasons, for the best aesthetic and functional result it offers. The transplant significantly reduced the healing time with better aesthetic and functional results. The burned surfaces left to direct healing took an average of 6 months to heal and there were associated complications such as formation of keloid scars, hypertrophic plaques and skin retractions leading to cosmetic deformities. The final results appear to be independent of the time required to complete the transplant, and it will be necessary to ensure that there is no local and systemic infection and anaemia. Conclusion: Total self-skin grafting still has its place in the initial management of burns in children. It offers good aesthetic and functional results.

Flap transplantation for treatment of pelvic fracture and defective hip

A case of flap transplantation for treatment of pelvic fracture and defective hip in the Third Affiliated Hospital of Inner Mongolia Medical University was collected and analyzed on the basis of diagnosis,physical examination and treatment.The patient was in serious condition with large necrotic area and prone to lead to various complications.The paper aims to share experience and provide references for similar cases amongst surgeons.

Comparison of Minimal Skin Incision Technique in Living Kidney Transplantation and Conventional Kidney Transplantation

Background：Recently,the most common incision for kidney transplantation （KT） is an inverted J-shaped incision known as the ＆quot;hockey-stick.＆quot; However,demands for minimally invasive surgery in KT are increasing as in other various fields of surgery.Hence,we evaluated whether there is difference between minimal skin incision technique in kidney transplantation （MIKT） and conventional KT （CKT）.Methods：Between June 2006 and March 2013,a total of 452 living kidney transplant patients were enrolled.The MIKT group included 17 young unmarried women whose body mass index was 〈25 kg/m^2 and had no anatomic variation.The CKT group included 435 patients.The MIKT operation technique restricted to the 10 cm-sized skin incision in the lower right abdomen from laterally below the anterior superior iliac spine to the midline just above the pubis was performed.We compared the baseline clinical characteristics and postoperative results between two groups.For proper comparison,propensity score matching was implemented.Results：There was no difference in graft function,survival,and postoperative complication rate between MIKT and CKT groups （all P 〉 0.05）.The 5-year graft survival was 92.3% and 85.7% in MIKT and CKT groups,respectively （P =0.786）.Conclusions：Our results indicated that MIKT showed more favorable cosmetic results,and there were no statistical differences in various postoperative factors including graft function,survival,and complications compared with CKT.Hence,we suggested that MIKT is an appropriate method for selected patients in living KT.

Clinical efficacy of artificial skin combined with vacuum sealing drainage in treating large-area skin defects

Objective： To observe the clinical efficacy of artificial skin combined with vacuum sealing drainage （VSD） in treating large-area skin defects. Methods： Totally 18 patients with skin defects, treated with artificial skin combined with VSD from September 2008 to May 2009 in our hospital, were retrospectively analyzed in this study. There were 15 males and 3 females, aged 7-66 years, 34.3 years on average. Among them, 10 cases had skin laceration caused by traffic accidents （7 with open fractures）, 1 mangled injury, 1 blast injury, 1 stump infection combined with skin defects after amputation and 5 heel ulcers. Results： All skin grafts in 16 cases survived afterbeing controlled by VSD for one time. For the rest 2 patients, one with skin avulsion on the left foot was given median thickness skin grafts after three times of VSD, the other with open fractures in the left tibia and fibula caused by a traffic accident was given free flap transplantation. Skin grafts of both patients survived, with normal color and rich blood supply. Conclusion： Skin grafting in conjunction with artificial skin and VSD is much more effective than traditional dress- ing treatment and worth wide application in clinic.

Transplantation tolerance mediated by regulatory T cells in mice

Background With potent suppressive effect on responder T cells, CD 4 +CD 25 + regulatory T (Treg) cells have become the focus of attention only recently and they may play an important role in transplantation tolerance However, the mechanism of action is not clear This study was designed to assess the possibility of using CD 4 +CD 25 + Treg cells to induce transplantation tolerance and to investigate their mechanism of action KH*2/5DMethods CD 4 +CD 25 + Treg cells were isolated using magnetic cell separation techniques Mixed lymphocyte reactions were used to assess the ability of Treg cells to suppress effector T cells Before skin transplantation, various numbers of CD 4 +CD 25 +Treg cells, which have been induced using complex skin antigens from the donor, were injected into the host mice either intraperitoneally (0 5×10 5, 1×10 5, 2×10 5, 3×10 5, 4×10 5, or 5×10 5) or by injection through the tail vein (5×10 3, 1×10 4, 2×10 4, 5×10 4, 1×10 5, 2×10 5) Skin grafts from two different donor types were used to assess whether the induced Treg cells were antigen-specific The survival time of the allografts were observed Single photon emission computed tomography was also used to determine the distribution of Treg cells before and after transplantation Results Treg cells have suppressive effect on mixed lymphocyte reactions Grafts survived longer in mice receiving CD 4 +CD 25 + Treg cell injections than in control mice There was a significant difference between groups receiving intraperitoneal injection of either 2×10 5 or 3×10 5 CD 4 +CD 25 +Treg cells and the control group ( P <0 05, respectively) Better results were achieved when Treg cells were injected via the tail vein than when injected intraperitoneally The transplantation tolerance induced by CD 4 +CD 25 + Treg cells was donor-specific Analysis of the localization of Treg cells revealed that Treg cells mainly migrated from the liver to the allografts and the spleen KH*2/5DConclusions CD 4 +CD 25 +Treg cells can induce donor-specific transplantation tolerance Cell-to-cell contact may be the primary mechanism by which Treg cells act on effector T cells

Dynamic changes of interleukin-1, interleukin-6 and tumor necrosis factor in intermingled skin graft in burned rats

To compare the dynamic changes of interleukin 1 (IL 1), interleukin 6 (IL 6), and tumor necrosis factor (TNF) in intermingled skin graft with those in other types of skin grafts in rats. Methods: A 10% 15% third degree burn was created in 180 Spregue Dawley (SD) rats. After removing the scar, skin grafts were performed on the open wounds immediately with autoskin (aus, n=54), alloskin (als, n=54) and intermingled skin (n=36). That is to say, in the intermingled skin graft, a big piece of alloskin (mals) was grafted first, and 3 days later, small pieces of autoskin (maus) were embedded in the alloskin. The rest 36 rats were taken as the controls. And the biological activities of IL 1, IL 6 and TNF in graft sheets in each group were detected after skin graft. Results: The levels of IL 1, IL 6 and TNF in the aus group decreased steadily after their initial elevations, whereas in the als group they increased significantly and kept on the peak level in the later phases. In the intermingled group, there appeared a lowest IL 1 level in the mals and a highest one in the maus simultaneously at 7 (4) days (The number out of parenthesis is the days after transplanting with alloskin sheets, and the number in parenthesis is the days after embedding autoskin sheets in the intermingled skin graft. Similarly hereinafter.) after skin graft (P< 0.01 ), and the high level in the maus abruptly decreased at 14 (11) days after skin graft. At exactly the same phase on day 7 (4), a prominent peaked IL 6 in the mals occurred. In the later phases, the levels of TNF remained relatively low both in the mals and in the maus. From day 7 (4) on, each cytokine fluctuation in the mals synchronized with that in the maus. The longer the post transplantation period lasted, the more the positive cytokine correlated between the mals and the maus. Conclusions: The low levels of IL 1 and TNF may be important factors to lighten the intensity of local rejection in the intermingled skin graft. The temporarily peaked IL 6 is both an inducer which induces the production of local IL 1 receptor antagonists and soluble TNF receptors and a signal which indicates a local enhancement of Th 2 cells. The mild rejection process and the synchronized cytokine level during the later phases suggest a possible chimerism between the mals and the maus.

Romidepsin(FK228) improves the survival of allogeneic skin grafts through downregulating the production of donor-specific antibody via suppressing the IRE1α-XBP1 pathway

Antibody-mediated rejection(AMR)is one of the major causes of graft loss after transplantation.Recently,the regulation of B cell differentiation and the prevention of donor-specific antibody(DSA)production have gained increased attention in transplant research.Herein,we established a secondary allogeneic in vivo skin transplant model to study the effects of romidepsin(FK228)on DSA.The survival of grafted skins was monitored daily.The serum levels of DSA and the number of relevant immunocytes in the recipient spleens were evaluated by flow cytometry.Then,we isolated and purified B cells from B6mouse spleens in vitro by magnetic bead sorting.The B cells were cultured with interleukin-4(IL-4)and anti-clusters of differentiation 40(CD40)antibody with or without FK228 treatment.The immunoglobulin G1(IgG1)and IgM levels in the supernatant were evaluated by enzyme-linked immunosorbent assay(ELISA).Quantitative reverse transcription-polymerase chain reaction(RT-q PCR)and western blotting were conducted to determine the corresponding levels of messenger RNA(mRNA)and protein expression in cultured cells and the recipient spleens.The results showed that FK228 significantly improved the survival of allogeneic skin grafts.Moreover,FK228 inhibited DSA production in the serum along with the suppression of histone deacetylase 1(HADC1)and HDAC2 and the upregulation of the acetylation of histones H2A and H3.It also inhibited the differentiation of B cells to plasma cells,decreased the transcription of positive regulatory domain-containing 1(Prdm1)and X-box-binding protein 1(Xbp1),and decreased the expression of phosphorylated inositol-requiring enzyme 1α(p-IRE1α),XBP1,and B lymphocyte-induced maturation protein-1(Blimp-1).In conclusion,FK228 could decrease the production of antibodies by B cells via inhibition of the IRE1α-XBP1 signaling pathway.Thus,FK228 is considered as a promising therapeutic agent for the clinical treatment of AMR.

A Review of Skin Banking Guidelines and Standards Worldwide:Towards the Harmonization of Guidelines for Skin Banking in Therapeutic Applications for the Regions under the Asia Pacific Burn Association(APBA)

Currently,there are no harmonized guidelines which govern skin banking in the Asia Pacific region.Therefore,skin banks are either unregulated or rely on their nation’s legislation or international accreditation to uphold their quality standards.A new set of skin banking guidelines was devel-oped through a comprehensive review and collation of best international practices for the Asia Pacific Burn Association(APBA)members,from donor screening and testing,to skin recovery,processing,storage and distribution,and quality assurance.National regulatory requirements reviewed include the European directives,Australia’s Therapeutic Goods Administration and Sin-gapore’s tissue banking standards.Further technical and quality management recommendations are referenced from the American Association of Tissue Banks(AATB),the United States Food and Drug Administration standards and guidance documents,various relevant European guides,Japanese Society of Tissue Transplantation guidelines and the Asia Pacific Association of Surgical Tissue Banking.Adapted mainly from the AATB standards,the new Asia Pacific Burn Association Guidelines for Skin Banking in Therapeutic Applications offer a comprehensive manual,address-ing:governance and contracts;staff responsibilities;quality management;facilities,equipment and supplies management;donor consent and testing;and recommendations of good practices pertaining to skin recovery,processing,storage and distribution.Besides complementing current generic regulations,they provide technical specifications of major aspects unaddressed in most legislations.This inaugural set of new regional skin banking guidelines would be a start for regional members of the APBA to adopt,and will hopefully culminate in a set of standards so that,in the long run,skin allografts from this region can be of similar quality,which can simplify import process and facilitate the exchange of allografts between members.