Objective To investigate the method and effectiveness of the digital artery series and parallel of island flap for repairing degloved injuries of the fingertip of thumb or adjacent finger Methods Between September 2008 and July 2012,the finger artery series retrograde island flaps tiled in the repair of finger degloving injury in 13 cases,repair of adjacent finger tip degloving injury in 11 cases; 8 cases of degloved injuries of the fingertip were tiled with the digital artery parallel island flap from ulnaris middle finger and radialis ring finger of arteria digitalis communis pedicled which were from the same palm side.The size of skin and soft tissue defect ranged from 2.0 cm × 1.8 cm-7.2 cm ×5.5 cm,gutted flap minimum ranged from 1.1 cm × 1.0cm-1.5 cm × 1.3cm,and the maximum ranged from 3.0 cm × 2.2 cm-5.5 cm × 4.5 cm.The donor sites were repaired with the intermediate split thickness free skin grafts and performed with pressure dressing.Results The group of 32 cases,in 1 case the flap vasospasm occurred in operation of free process,the symptoms disappeared after local application of papaverine and hot compress ; 1 case of flap occurred disturbance of blood circulation after operation because of tight suturing for pedicle,the symptoms relieved after removing the stitches at intervals; 2 cases blisters appeared after operation,disappeared after a week.All skin flaps were survived,incision and skin graft donor sites healed by first intention.Twenty patients were followed-up from 6 to 12 months after operation.All flaps presented the satisfactory appearance and texture,recovered protective feeling.At last follow-up,the two-point discrimination was 7 to 10mm,and the flexion and extension function of wounded fingers recovered to normal.According to the functional assessment criteria of upper limb formulated by the Hand Surgery Branch of Chinese Medical Association,there were excellent in 19 cases,good in 10 cases,and moderate in 3 cases.No significant loss to the donor shape and function.Conclusion The surgery by adopted the digital artery series or parallel of island flap for repairing degloved injuries of the fingertip of thumb or adjacent finger,not only has the advantages of simpleness,safety and reliability,but also can satisfy the patients who aren't willing to accept or because of physical reasons can't accept the treatment of abdominal skin tube or nail flap from hallux toe,which performs in both high-end and low level hospitals,and deserves of general application.

Objective:To observe the lipogenic or osteogenic differentiation of decellularized adipose matrix (DAM) in the periosteal microenvironment.Methods:From June 2020 to December 2020, adipose tissue obtained by human liposuction was prepared as DAM at the National Institute of Plastic Surgery. Six male SD rats of 4 to 6 weeks were selected and implanted into the subperiosteum of the rat parietal bone according to the same initial volume. After 12 weeks, adipogenesis and osteogenic differentiation of DAM were observed by gross specimens, histological staining, and immunofluorescence staining. Label-free quantitative protein mass spectrometry was used for detection of osteogenic-associated proteins in DAM.Results:Vascularization around the DAM was evident. Adipogenesis and angiogenesis were observed in DAM by H&E and Masson staining, while OCN immunofluorescence staining confirmed osteogenic differentiation of DAM. The osteogenic differentiation related proteins were screened by mass spectrometry.Conclusions:In the microenvironment of periosteum, DAM mainly differentiates towards adipose tissue, but a few of them havs the potential to differentiate towards osteogenesis, which might be related to some of the osteogenesis-related proteins contained in DAM.

Many severe trauma, tumor and congenital malformation often lead to facial disfigurement. Facial allotransplantation can repair severe deformities in one operation and achieve both functional and aesthetic recovery. By 2018, 44 partial or full facial allotransplantations have been performed worldwide. While, facial allotransplantation was a non-life saving operation, and there were much discusion and controversial. Based on the previous experience, the selection of surgical indications, surgical principles and details, prevention and management of postoperative complications, immunosuppression programs, postoperative functional recovery, ethical issues, social-economic issues were analyzed and discussed.

Many severe trauma, tumor and congenital malformation often lead to facial disfigurement. Facial allotransplantation can repair severe deformities in one operation and achieve both functional and aesthetic recovery. By 2018, 44 partial or full facial allotransplantations have been performed worldwide. While, facial allotransplantation was a non-life saving operation, and there were much discusion and controversial. Based on the previous experience, the selection of surgical indications, surgical principles and details, prevention and management of postoperative complications, immunosuppression programs, postoperative functional recovery, ethical issues, social-economic issues were analyzed and discussed.

Objective:The study aimed to investigate the effect of exosomes derived from bone marrow mesenchymal stem cells (BMSC-Exo) in promoting angiogenesis of fat grafts by regulating Notch signaling pathway.Methods:Fat from the abdomen of a 30-year-old healthy female who received liposuction in the Department of Plastic Surgery of the First Affiliated Hospital of Air Force Military Medical University in August 2020 was collected. Fat transplantation models were established using 12 BALB/c nude mice, with 0.5 ml of processed fat particles injected into the left and right sides of the backs. 100 μl BMSC-Exo (50 μg) was injected into the left side of the back of nude mice once per week for 4 weeks after fat grafting, which was the exosome group. The right side of the back was injected with 100 μl of phosphate-buffered saline at the same time points for 4 weeks after fat grafting, which was the control group. The following items were observed: (1) Fat grafts were collected and weighed at 4 weeks and 8 weeks after transplantation, the retention rate was calculated. (2) HE staining and immunofluorescence staining of Perilipin A was used to visualize the structure and integrity of adipocytes at 8 weeks after transplantation. (3) At 8 weeks after transplantation, immunohistochemical staining was used to detect CD31 positive cells, calculate micro vessel density, detect Notch1 and Notch4 positive cells and calculate the proportion of positive area.(4) At 8 weeks after transplantation, the relative expressions levels of Notch1, Notch4 and VEGF mRNA in fat grafts were detected by real-time fluorescence quantitative PCR. The data were analyzed by Graphpad Prism 8.0. T-test was used for comparison between groups. P<0.05 indicated the difference was statistically significant. Results:(1) At 4 and 8 weeks after transplantation, the retention rates of adipose tissue wet weight in the control group were (41.15±9.68)% and (34.30±6.45)% respectively. The results in the exosome group were (61.77±10.98)% and (55.93±5.89)%, which were higher than those in the control group ( P<0.05). (2) At 8 weeks after transplantation, the structural integrity of adipocytes in the exosome group was better than the control group, with more neovascularization. There were more intact Perilipin A positive adipocytes in the exosome group and less in the control group. (3) At 8 weeks after transplantation, the density of micro vessels in the control group was 4.67±0.57, which was significantly lower than that in the exosome group (13.00±2.00, P<0.05). The proportion of Notch1 and Notch4 positive area per visual field in the control group was lower than that in the exosome group [(0.53±0.28)% vs. (1.67±0.11)%, (0.11±0.06)% vs. (1.20±0.24)%, P<0.05]. (4) The mRNA expression levels of Notch1, Notch4 and VEGF were 1.53±0.20, 1.50±0.26 and 2.56±0.55 in the exosome group, which were significantly higher than those in the control group (1.00+ 0.00) ( P<0.05). Conclusions:BMSC-Exo may promote angiogenesis and improve retention rate of transplanted fat grafts through the elevation of VEGF expression and the activation of Notch signaling pathway.

Objective:The study aimed to investigate the effect of exosomes derived from bone marrow mesenchymal stem cells (BMSC-Exo) in promoting angiogenesis of fat grafts by regulating Notch signaling pathway.Methods:Fat from the abdomen of a 30-year-old healthy female who received liposuction in the Department of Plastic Surgery of the First Affiliated Hospital of Air Force Military Medical University in August 2020 was collected. Fat transplantation models were established using 12 BALB/c nude mice, with 0.5 ml of processed fat particles injected into the left and right sides of the backs. 100 μl BMSC-Exo (50 μg) was injected into the left side of the back of nude mice once per week for 4 weeks after fat grafting, which was the exosome group. The right side of the back was injected with 100 μl of phosphate-buffered saline at the same time points for 4 weeks after fat grafting, which was the control group. The following items were observed: (1) Fat grafts were collected and weighed at 4 weeks and 8 weeks after transplantation, the retention rate was calculated. (2) HE staining and immunofluorescence staining of Perilipin A was used to visualize the structure and integrity of adipocytes at 8 weeks after transplantation. (3) At 8 weeks after transplantation, immunohistochemical staining was used to detect CD31 positive cells, calculate micro vessel density, detect Notch1 and Notch4 positive cells and calculate the proportion of positive area.(4) At 8 weeks after transplantation, the relative expressions levels of Notch1, Notch4 and VEGF mRNA in fat grafts were detected by real-time fluorescence quantitative PCR. The data were analyzed by Graphpad Prism 8.0. T-test was used for comparison between groups. P<0.05 indicated the difference was statistically significant. Results:(1) At 4 and 8 weeks after transplantation, the retention rates of adipose tissue wet weight in the control group were (41.15±9.68)% and (34.30±6.45)% respectively. The results in the exosome group were (61.77±10.98)% and (55.93±5.89)%, which were higher than those in the control group ( P<0.05). (2) At 8 weeks after transplantation, the structural integrity of adipocytes in the exosome group was better than the control group, with more neovascularization. There were more intact Perilipin A positive adipocytes in the exosome group and less in the control group. (3) At 8 weeks after transplantation, the density of micro vessels in the control group was 4.67±0.57, which was significantly lower than that in the exosome group (13.00±2.00, P<0.05). The proportion of Notch1 and Notch4 positive area per visual field in the control group was lower than that in the exosome group [(0.53±0.28)% vs. (1.67±0.11)%, (0.11±0.06)% vs. (1.20±0.24)%, P<0.05]. (4) The mRNA expression levels of Notch1, Notch4 and VEGF were 1.53±0.20, 1.50±0.26 and 2.56±0.55 in the exosome group, which were significantly higher than those in the control group (1.00+ 0.00) ( P<0.05). Conclusions:BMSC-Exo may promote angiogenesis and improve retention rate of transplanted fat grafts through the elevation of VEGF expression and the activation of Notch signaling pathway.

Objective:To investigate the immobilizing effect of full-thickness skin subcutaneous grafting on allogeneic full-thickness skin graft in rats.Methods:The experimental research method was used. The inbred male Brown-Norway rats ( n=10) and Lewis rats ( n=10) were used as donors and recipients respectively. After subcutaneously full-thickness separation of a 2.2 cm×2.2 cm area on the nape of the recipient rat, a full-thickness skin of 2.0 cm×2.0 cm taken from the abdomen of the donor rat was subcutaneously grafted, and the donor site was pulled together and sutured. The autologous skin over the allograft in the recipient rat was excised 5-6 d after grafting, and the stitches were removed 7 d after excision. Within 2 months after grafting, the feeding, activity, and survival of the donor and recipient rats, behavior of tearing and scratching the wounds of the recipient rats, the wound condition after autologous skin excision in recipient rats, and the survival and hair growth of the grafted allogeneic skin were observed. Results:Within 2 months after grafting, the donor and recipient rats all ate normally and could move freely with no abnormal death. No tearing or scratching of the wounds occurred in recipient rats. There was a small amount of exudation and partial epidermal desquamation after autologous skin excision in recipient rats. All transplanted allografts survived, which were free of infection and necrosis, with new hairs growing out smoothly.Conclusions:The immobilizing method of full-thickness skin subcutaneous grafting of allogeneic full-thickness skin graft in rats is simple and time-saving without postoperative dressing change, with reliable pressure fixation and high survival rate of skin grafts, which can be promoted for animal skin grafting models.