Improvements in severe burn and trauma care have enabled patients to survive massive bums and severe injury that would have once been fatal.Now up to 40％-70％ of patients develop hypertrophic scars after bums and trauma.The functional and psychosocial sequelae remain a major rehabilitative challenge,decreasing quality of life and delaying reintegration into society.So far,including surgical treatment,existing scar treatments have different degrees of limitations.In recent years,flap surgery and wound repair technology develop rapidly,such as perforator flap,flap dilation techniques,autologous scar composite skin,negative pressure wound treatment technology,the new technology of 3D and 4D bioprinting technology etc.These new technologies provide high quality tissue repair materials for clinical treatment of scar repair have a broad prospect of clinical application,and have achieved more satisfactory clinical repair treatment effect.The future need is to further strengthen the practice and innovation of scar repair,and the basic research and clinical application of scar should be strengthened and combined closely.The new elucidation of the scar prevention and therapeutic strategies should be put foward to improve the prognosis of patients with scar and the quality of life.

To investigate the optimum transfection condition in transfecting human keratinocytes with plasmid-liposome complexes in vitro,the cultured human keratinocytes at 60% ～ 100% confluences were exposed to the eukaryotic expression plasmid,pCMV*SPORT-β-gal,coated with LipofectAMINE in different DNA/liposome mixing concentration ratios.After cultured for another 48 hours following the ends of 6 ～ 24 hours exposures to the DNA-liposome complexes,the transfected human keratinocytes were visualized by β-galactosidase staining.Then,the transfection efficiency was determined by calculating the rate of β-galactosidase staining positive cells.β-galactosidase expression was showed clearly in human keratinocytes transfected with the DNA-liposome complexes.The highest efficiency was achieved with cultured cells at 80% and 90% confluences,demonstrating by the transfection rates of (31.35±1.35)% and (32.32±2.47)% respectively.Meanwhile,the essential transfection conditions for these efficiencies were in coating pCMV*SPORT-β-gal DNA of 1.5μg/100μL with LipofectAMINE of 12.5μL/100μL,and exposing the cells to the DNA-liposome complexes for 8 hours.These results indicate that LipofectAMINE could effectively transfer eukaryotic expression plasmid into human keratinocytes in vitro,for which the optimization of transfection conditions involve in cells growth state,DNA/liposome mixing concentration ratio,and exposure time of cells to DNA-liposome complexes.

Objective To explore the indications and curative effect of minimally invasive pedicle screw fix-ation in the treatment of thoracolumbar fractures .Methods 10 patients with thoracolumbar fractures without neuro-logical damage and the need for vertebral lamina decompression were selected .Under the C arm,the disease vertebral and adjacent vertebral arch spikes were positioned ,four 2.5cm long incisions were done ,fixation and restoration were completed within four small incisions .Results All patients restored vertebral body height and protrusion deformity after correction.The operation time was about 2h,blood loss was 100~150mL.Conclusion The minimally invasive pedicle screw fixation in the treatment of thoracolumbar fractures is suitable for simple thoracolumbar fractures without neurological damage ,the need for patients with vertebral lamina decompression ,it has advantages of small trauma ,fas-ter postoperative recovery .

Objective To investigate the application of B -Learning mode in the teaching of department of burns surgery.Methods 234 students were divided into two parts by digital table method randomly.The experimental group was applied by the means of B -learning mode,while the control group was taught by the traditional way.And the results were evaluated.Results The basic theory scores(75.39 ±12.04)points in the students of experimental group were higher than those of the control group(68.27 ±12.38)points.The practice scores(76.42 ±11.89)points in the students of experimental group were higher than those of the control group(65.36 ±12.05)points.Students'professional knowledge scores(79.92 ±12.85)points in the experimental group were higher than those of the control group(71.56 ±13.01)points.Both percentage and score were higher in the experimental group than in the control group in comprehensive ability.Conclusion Blending learning gives students a potential time,environment and recourse to learn.By integrating learning ability and nursing skills improved,B -learning mode plays an important role in improving the quality of burn department internship.

Hyperplastic scar and contracture are two mainly respects that contribute to poor functional recovery of the patients after burn.The principles of prevention and management of the scar were reviewed in the article and the methods in facilitating functional recovery were also discussed as well.

Objective To evaluate operative methods and the clinical effect for comminuted calcaneal fractures.Methods 21 cases(24 feet)of comminuted calcaneal fractures were treated by one stage bone grafting plus open reduction and internal fixation with plastic calcaneus titanium plate.The fractures were classified according to the Sanders system into Sanders Ⅱ,Ⅲ and Ⅳ subgroups.Results All cases were followed up for 9～20 months(14months in average).All cases recovered with good healing of fracture.According to Maryland score,the results were excellent in 14 feet,good in 7 feet,fair in 2 feet,and poor in 1 foot.The excellent and good rate was 87.5％.Conclusions By using the method of internal fixation with plastic calcaneus titanium plate,fracture site can be well exposed,which is helpful to recover calcaneus to its normal length,width,height,Gissane angle and Bohler angle.A reliable internal fixation is helpful for early stage functional excise after surgery,which can maximize the recovery of the ankle function.

Objective To investigate the difference of vacuum sealing drainage (VSD) on the effect of one-stage skin graft and second-stage sugery after scar release.Methods A total of 42 patients who wanted to undergo scar release and skin graft was randomly divided to control group (n =21) and VSD treatment group (n =21).The control group implemented skin graft immdiately after scar release while VSD treatment group were treated with VSD for 3 days after scar release and then implemented skin graft.The rate of subcutaneous blood stasis and the survival rate of skin graft were observed at 7 days after skin graft.The condition of grafted skin contracture and hyperplasia after half a year was also observed.Results The incidcnce of subcutaneous blood stasis was significantly lower in the VSD group than that in the control group (P ＜ 0.05).The survival rate of skin grafts was significantly higher in the VSD group than that of the control group (P ＜ 0.05).The score of Vancouver scar was significantly lower in the VSD group than that in the control group (P ＜ 0.05).Conclusions VSD treatment of second-stage sugery after scar release can reduce the occurrence of subcutaneous blood stasis,promotc skin graft survival,reduce postoperative skin graft contracture and improve the prognosis of patients compared to one-stage skin graft.

Objective To explore the repair effect of the superficial iliac island flap for the hypertrophic scar of mons pubis after burned.Methods From July 2013 to July 2016,the author had treated 26 patients with mons pubis hypertrophic scar after burned.There were 19 males and 7 females among them.The age was from 1 year and 5 months to 10 years old.The scar area was of 6 cm ×5 cm-15 cm ×8 cm.Some of the patients had external genital malformations caused by scar contracture.Surgery removed the scar and completely released the basic shape of the vulva.It had to expand the superficial iliac island flap of 1 cm according to the size of the wound,and sufficient length of vascular pedicle according to the distance from the wound to the flap.The flap was cut in the superficial of the deep fascia,and reserved about 2cm wide fat along the superficial iliac artery.The superficial vein was located in the fat.The wound was covered by the flap,which was rotated directly or through a subcutaneous tunnel.Results Twenty six patients were treated with a single operation and no vascular crisis occurred.All the flaps survived.One patient delayed incision healing due to the high incision tension,and the remaining patients were in primary healing.The postoperative follow-up found that all the flaps had thin thickness,similar color to the surrounding skin,soft texture and feeling.Conclusions There are obvious signs of scarring in the mons pubis area after deep burns,and scar contracture can cause vulvar deformity.The superficial iliac island flap,which has a thin thickness,soft texture,similar color,and can be sutured directly for the donor site,is a good choice to repair the mons pubis hypertrophic scar.

Objective To investigate the effeets of insulin on the apoptosis of vascular endothelial cells cuinduced by burn$eruln in order to explore its possible mechamsm.Method Cultured human ECV304 cells were randomly divided into 33x)ups:control group,the ECV304 cells hured by 15%(V/V)rat normal,qertlm(t=6);bum semm group,the ECV3()4 cells simulated by 15%(V/V)self-made burn semm collected from rats with 30%TBSA full-thickness burns on the,back(n=6);and burn Serum+insulin group.the ECV304 cells cultared by insulin(10-7mol/L)and 15%(V/V) seIf-made rat bum serum(n=6).The transferase mediated nick end labeling(TUNEL) method was employed to measure the apoptosis of endothelial cells at 6 hours after stimulation.Meanwhile.immanohistochemical technique and Western blotting were used to determine the protein expressions of bcl-2 and eNOS.Data are expressed ills mean ±SEM.Statistical comparison was made using oneway analysis of vtriance.Significance was accepted at P<0.05.Results Compswith the control group,bum$erunl induced the apoptusis(18.5±3.1%)and down-regalated bcl·2(O.36±0.12)and p-eNOS(O.55±0.28)protein expressions of HUVECs(P<0.01).Burn 9AJ'unl+insulin significantly decreased the apoptosis(9.6 4-2.8%)and up-regulated bcl-2(0.944-0.25)and p-eNOS(0.89±0.16)protein expressions ofHU-VECs in comparison with the bum serllm group(P<0.01).eNOS showed no significant differences in three groups.Conclusions Insulin could markedly inhibit the apoptosis and up-regalate bcl-2 protein expression of HUVECs induced by bum serum,and its mec,harfism might involve the protein expression ofphosphorylated eNOS.

BACKGROUND: Mesenchymal stem cells (MSCs), with low immunogenicity, can regulate cellular immunity and mitigate graft rejection, which has a good prospect in tissue engineering. However, it is rarely present in bone marrow. OBJECTIVE: To explore an isolation and culture method of the rabbit bone marrow-derived MSCs, to observe the biological characteristics and differentiation potential of bone marrow-derived MSCs.METHODS: MSCs were isolated from rabbit tibia bone marrow by combination of gradient centrifugation and different adherent method, then proliferation in vitro. Morphology was examined by phase contrast microscopy, and the growth curve of cultured MSCs was drawn via MTT results. MSCs were treated with osteogenetic inductor (L-DMEM/F12, 10% fetal bovine serum, 0.1 μmol/L dexamethasone, 200 μmol/L vitamin C, 10 mmol/L β-phosphoglycerol), adipose inductor (L-DMEM/F12, 10% FBS, 1 μmol/L dexamethasone, 200 μmol/L antifani, 0.5 mmol/L IBMX, 10 μg/mL insulin), and chondrocytes inductor (L-DMEM/F12, 10% FBS, 10 μg/L TGF-β1, 0.1 μmol/L dexamethasone, 50 μmol/L vitamin C, 6.25 mg/L insulin) to differentiated into osteoblast, dipocytes and chondrocytes. And the differentiated cells were identified by alkaline phosphatase staining, oil red O staining, and toluidine blue staining, respectively.RESULTS AND CONCLUSION: Bone marrow-derived MSCs can be isolated and cultured by the combination of gradient centrifugation and different adherent method in vitro, which have the better potentiality of proliferation and multi-directional differentiation. Mostly of the primary and passaged cells were spindle-shaped. After osteogenetic induction, cells were positive to alkaline phosphatase staining. Oil red O staining showed that red lipid droplet existed in adipose cells, and toluidine blue staining showed that toluidine blue was positive after chondrocytes induction.