Objective:To investigate the conversion of stromal vascular fraction (SVF) in the microenvironment of radiation-induced skin injuries to provide guidance for clinical applications.Methods:Based on a random number table, C57BL/6N mice were categorized into four groups: the blank control, negative control, acute injury, and chronic injury groups, with each group containing 25 mice. The backs of mice in the blank control, acute injury, and chronic injury groups were exposed to 15 Gy X-ray irradiation. Then, the mice in the negative control, acute injury, and chronic injury groups were injected subcutaneously with the SVF derived from B6/G-R mice. The survival of these mice was observed 1, 3, 7, 14, and 21 d after the injection through fluorescence tracing and in vivo imaging. Accordingly, the clinical SVF injection regimens were optimized based on the experimental result of mice. Finally, local SVF injection was performed on different frequencies for patients in different wound conditions, with the efficacy being observed. Results:The fluorescence of SVF was observed from the tissue slices of the acute injury, chronic injury, and negative control groups 14 d post-injection. The result showed that the fluorescence intensity of SVF 1, 3, and 7 d post-injection was in the order of the negative control group > the acute injury group > the chronic injury group. The acute injury group ranked at the top and the chronic injury group remained at the bottom 14 d after the injection. The fluorescence of SVF in each group was barely detected 21 d after the injection. Compared to the negative control group, the acute injury group exhibited statistical differences only 14 d post-injection ( t = 4.11, P < 0.05), while the chronic injury group displayed statistical differences 1, 3, 7, and 14 d after the injection ( t = 3.88-5.74, P < 0.05). Furthermore, the acute injury group exhibited significantly higher fluorescence intensity of SVF than the chronic injury group ( t = 4.73-8.38, P < 0.05). The half-life of SVF for the negative control, acute injury, and chronic injury groups was 6.336, 6.014, and 2.163 d, respectively. As indicated by the application of SVF transplantation based on traditional surgical protocols in the clinical trial, SVF can significantly promote wound repair, with earlier SVF transplantation being more beneficial for wound healing. Conclusions:The conversion of SVF differs in the microenvironments of acute and chronic radiation-induced skin injuries. This can serve as an essential guide for the administration timing and injection frequency of SVF in clinical applications.

Objective:To investigate the application value of jigsaw puzzle flap based on free-style perforator in repairing the defect on groin and adjacent organ after tumor extended resection.Methods:From December 2013 to August 2019, the data was focused on the patients who underwent soft tissue defect repair of groin and adjacent areas in the Second Affiliated Hospital of Chengdu Medical College. After the defect was predetermined preoperatively, portable ultrasound Doppler was used to map multiple perforators adjacent to the defect. The large defect was divided into several small parts, based on the location of perforators, the intensity of the Doppler, the safety size of flap that can be perfused by a single free-style perforator, and the donor sites can be closed primarily. Each component part corresponds to a free-style perforator flap. The perforator vessels were reversely dissected, and small flaps of V-Y advancement, rotation and propeller pedicled with perforator vessels were formed (appropriate modification of flaps can be made according to actual anatomical perforator vessels). All flaps were transferred to the defect site and reassembled according to the preoperative design (film simulation) to repair the large wound or deep space after the extended resection of the tumor in the groin and adjacent organs. Meanwhile, the donor site was closed and sutured primarily. The color, temperature, capillary reaction of the skin flap were observed during the first 3 days after procedure, and appearance and function after repair were observed after long-term follow-up.Results:A total of 31 patients were enrolled, including 18 males and 13 females. The ages of the patients ranged from 48 to 82 years with an average of 66 years. The defect area of skin and soft tissue was 8.0 cm×10.0 cm-15.5 cm×20.0 cm, with an average of 12.0 cm×15.0 cm. A total of 65 flaps were harvested, including 32 propeller flaps, 18 rotating flaps and 15 V-Y advancement flaps. There were 3 cases with 3 flaps and 28 cases with 2 flaps. The average skin flap area was 12.0 cm×20.0 cm-5.0 cm×10.0 cm, with an average of 8.0 cm×13.0 cm, and the diameter of the pedicle perforator vessel was 0.5 mm-4.0 mm. The color, temperature and capillary reaction of the skin flap were normal during the first 3 days after operation. Too much tension resulted in congestion of the flap in one case and poor wound healing. The wound was treated with dressing change, and healed in two weeks. The patients were followed up for 3 months to 5 years, with an average of 1.5 years. 30 patients survived primarily. The postoperative appearance was good.Conclusions:The combination of multiple small free-style perforator flaps can repair the large skin and soft tissue defects of malignant tumors after extensive resection on the groin and its adjacent area, and the donor site can be closed primarily. This method is easy to operate and avoids micro anastomosis and skin grafting. It is a kind of repair approach for clinical reference.

Objective:To investigate the application value of jigsaw puzzle flap based on free-style perforator in repairing the defect on groin and adjacent organ after tumor extended resection.Methods:From December 2013 to August 2019, the data was focused on the patients who underwent soft tissue defect repair of groin and adjacent areas in the Second Affiliated Hospital of Chengdu Medical College. After the defect was predetermined preoperatively, portable ultrasound Doppler was used to map multiple perforators adjacent to the defect. The large defect was divided into several small parts, based on the location of perforators, the intensity of the Doppler, the safety size of flap that can be perfused by a single free-style perforator, and the donor sites can be closed primarily. Each component part corresponds to a free-style perforator flap. The perforator vessels were reversely dissected, and small flaps of V-Y advancement, rotation and propeller pedicled with perforator vessels were formed (appropriate modification of flaps can be made according to actual anatomical perforator vessels). All flaps were transferred to the defect site and reassembled according to the preoperative design (film simulation) to repair the large wound or deep space after the extended resection of the tumor in the groin and adjacent organs. Meanwhile, the donor site was closed and sutured primarily. The color, temperature, capillary reaction of the skin flap were observed during the first 3 days after procedure, and appearance and function after repair were observed after long-term follow-up.Results:A total of 31 patients were enrolled, including 18 males and 13 females. The ages of the patients ranged from 48 to 82 years with an average of 66 years. The defect area of skin and soft tissue was 8.0 cm×10.0 cm-15.5 cm×20.0 cm, with an average of 12.0 cm×15.0 cm. A total of 65 flaps were harvested, including 32 propeller flaps, 18 rotating flaps and 15 V-Y advancement flaps. There were 3 cases with 3 flaps and 28 cases with 2 flaps. The average skin flap area was 12.0 cm×20.0 cm-5.0 cm×10.0 cm, with an average of 8.0 cm×13.0 cm, and the diameter of the pedicle perforator vessel was 0.5 mm-4.0 mm. The color, temperature and capillary reaction of the skin flap were normal during the first 3 days after operation. Too much tension resulted in congestion of the flap in one case and poor wound healing. The wound was treated with dressing change, and healed in two weeks. The patients were followed up for 3 months to 5 years, with an average of 1.5 years. 30 patients survived primarily. The postoperative appearance was good.Conclusions:The combination of multiple small free-style perforator flaps can repair the large skin and soft tissue defects of malignant tumors after extensive resection on the groin and its adjacent area, and the donor site can be closed primarily. This method is easy to operate and avoids micro anastomosis and skin grafting. It is a kind of repair approach for clinical reference.

Objective:To investigate radiation-induced somatic mutations and variations and provide theoretical basis for clarifying radiation-induced genetic changes and long-term effects by whole-genome sequencing analysis of the genetic variations of the victim of the " 5.7" 192Ir radiation accident in Nanjing. Methods:Normal back skin tissue, irradiated bone and soft tissues, and peripheral blood were collected from the victim 2 047 days post-irradiation. DNA of these samples was extracted and sequenced with high-throughput genomics and analyzed by bioinformatics method. The genetic variations of between irradiated and normal tissues were compared.Results:Compared with normal back skin tissue, there are large amounts of genetic variations in the irradiated bone and soft tissues and peripheral blood, including base substitution (transition, transversion), small insertion, small deletion, copy number variation (gain, loss) and structure variation (large deletion, large duplication, inversion, intra-chromosomal translocation, inter-chromosomal translocation). There were 10 666 genetic variations in the irradiated bone and soft tissues and 11 233 genetic variations in peripheral blood, where thousands of genes were involved in. These variations occurred in the exons, introns, UTR′3, UTR′5, splicing sites, within 5 kb upstream of transcription initiation site, within 5 kb downstream of transcription termination site, ncRNA and intergenic region. All chromosomes had genetic variations.Conclusions:There were a large number of genetic variations in the irradiated tissues and blood of the victim at 2 047 days after irradiation, which may affect the body function and cause the long-term effects.

Objective:To investigate the effect of ionizing radiation on the ferroptosis of skin cells and the potential therapeutic strategy of ferroptosis inhibitor Ferrostatin-1 (Fer-1) on irradiated skin cells.Methods:HaCaT cells were pre-treated with Fer-1 before X-ray irradiation. After irradiation, CCK-8 assay and LDH release assay were used to detect cell viability and cell death, flow cytometry was used to detect the lipid peroxidation levels, crystal violet staining assay was used to detect colony forming ability, and the expressions of ferroptosis related proteins ACSL4 and GPX4 were detected by Western blot.Results:The cell viability of HaCaT cells was significantly decreased ( t=5.63, 8.74, P<0.05) and the release of LDH was significantly increased ( t=3.98, 5.08, 9.27, P<0.05) after different doses of X-ray irradiation. The cell viability was improved ( t=5.79, P<0.05) and the release of LDH was reduced ( t=12.36, 11.96, 18.13, 9.96, P<0.05) after the pre-treatment with Fer-1. The lipid peroxidation levels of HaCaT cells were significantly increased ( t=9.59, P<0.05) and the clonogenic survival ability were reduced ( t=4.26, P<0.05) after 10 Gy X-ray irradiation, while Fer-1 pre-treatment reduced ( t=6.48, 17.04, P<0.05) the increase of lipid peroxidation level induced by X-ray irradiation and also effectively restore ( t=3.96, P<0.05) the clonogenic survival ability. The expressions of ACSL4 and GPX4 were decreased after 10 Gy X-ray irradiation, while they recovered to normal level ( t=5.23, 7.16, 4.78, 8.29, 6.43, P<0.05) after the pre-treatment with Fer-1. Conclusions:Ferroptosis inhibitor Fer-1 alleviates the progress of radiation-induced skin injury by inhibiting ferroptosis after ionizing radiation at the cellular level, which provides a potential strategy for the protection of radiation injury.

Endophytic fungi are promising producers of bioactive small molecules. Bioinformatic analysis of the genome of an endophytic fungus

Objective: To evaluate the parabiotic tissue protection concept in the repairment of acute radiation-induced skin injury. Methods: Seven patients(3 males and 4 females) with acute radiation injury treated in the Department of Plastic Surgery of the Second Affiliated Hospital of Soochow University from February 2014 to January 2018. The ages of patients ranged from 45 to 76 years. The wound areas include perineum and buttock (n=3), chest(n=2), and thigh(n=2). In the early stage, subregional " sandwich" surgical dressing was used to protect the probiotic tissue. Two months later, the necrotic tissue was clearly demarcated, the debridement was underwent, and the parabiotic tissue was preserved as far as possible. Vacuum sealing drainage(VSD)was applied to cover and soak wound with normal saline to moisturize the wound and promote the benign transformation of ecological tissue. Ten days later, the granulation grown well, and the skin flaps and myocutaneous flaps with good blood supply were designed to repair the wounds. The VSD device was continued to be used, to drain effusion under flap and promote the growth of cystic cavity granulation, with the purpose to promote blood supply of the skin flap, perform the final biological cleaning effect on the parabiotic tissue of the wound surface, promote the benign transformation of parabiotic tissue, and reduce the further necrosis. Results: Seven patients with Ⅳ degree acute radiation-induced injury wounds were treated 6-10 weeks for surgery preparation, and 2-4 weeks for VSD-application after debridement. Except for part of flap was necrotized on 10th day after the first operation in one patient, all the other patients achieved satisfied outcome in a surgery. There was no further radiation-induced ulcer occurred during the 0.5-3 years of follow-up. Conclusions The concept of parabiotic tissue protection during preoperative, intraoperative and postoperative recovery phase can promote parabiotic tissue transformed to a good result after acute radiation injury, and reduce the size and depth of soft tissue necrosis, which can provide a good foundation for the secondary repair with flap and reduce complications.

Objective To explore the clinical significance of protection "Choke vessel area" in the application of perforator flap to repair large defect of trunk after tumor resection.Methods A total of 62 patients (38 males and 24 females,aged from 19 to 79 years) from the Department of Plastic Surgery,Second Affiliated Hospital of Suzhou University underwent reconstructive surgery for large area defects of the trunk from March 2012 to January 2016.The perforator flap was designed according to the perforator location detected by Doppler before surgery.The flaps were harvested on the pedicle of perforators and dissected on the deep layer of deep fascia (including part of the myolemma).The areas of flap ranged from 5.0 cm × 10.0 cm to 19.0 cm × 22.0 cm.The donor site was sutured directly or local flap was transferred to repair.Results Flaps survived well in 59 of the 62 cases.The tip of flap was necrotic and healed after dressing change in 1 diabetic patient.The distal part of flap was necrotic on cuticular layer and healed after dressing change in another patient with scrotal defect.One patient had flap necrosis 10 days after operation and was repaired twice.The results were satisfied after following-up from 3 months to 2 years for 17 cases and from 6 months to 2 years for 25 cases.Fibrosarcoma protuberant and squamous cell carcinoma recurred in 1 case each,but the function and appearance were satisfactory after primary repair.Conclusions The procedure of preserving Choke vessel area can improve the blood supply of perforator flap and obtain larger survival area and survival quality.It is worthy of clinical application.

Objective: To introduce the application of free-style perforator flap based on aesthetic units to repair facial defect after tumor resection. Methods: By following the concept of free-style perforator flap and the principle of facial aesthetic unit, the design of a free-style perforator flap allowed over any nearby cutaneous vessel chosen purely on the characteristics of its Doppler signal. Conventional knowledge of anatomical landmarks and possible vascular variations were less relevant. A greater freedom in flap selection was gained to recover defect in different forms such as rotation flap, advanced flap and propeller flap, which were all based on free-style perforators. The flap size ranged from 1.5 cm×1.0 cm to 12.0 cm×6.0 cm with the perforator diameter of 0.3-3.0 mm in pedicle, and some of the pedicles are "perforator clusters" . Results: A total of 72 cases underwent surgery, and 68 cases survived completely with satisfactory appearance. 1 case healed two weeks later through dressing due to undesired healing, which result ed from high tension secondary postoperative blooding. 3 cases healed in a delay due to congestion and gained acupuncture treat. Conclusions The free-style perforator flap, which depended on Doppler-discerned perforator and facial aesthetic unit, represents safe, reliable and versatile for repairing facial defect after extended resection, and it not only offers a greater freedom in flap selection but also provides good aesthetic result.

Objective: To analyze effects of cooperation between physicians in department of burn surgery and department of intensive care medicine on rescue and treatment of severe mass burn patients involved in August 2nd Kunshan factory aluminum dust explosion accident. Methods: On August 2nd, 2014, 15 extremely severe burn patients involved in August 2nd Kunshan factory aluminum dust explosion accident were admitted to temporary burn treatment center established in Department of Critical Care Medicine of the Second Affiliated Hospital of Soochow University. The 15 patients were equally divided into 3 groups, with 5 patients in each group. Fifteen surgeons and 30 nurses from department of burn surgery and 15 physicians and 30 nurses from department of intensive care medicine from different hospitals in China were divided into 3 groups, with 5 physicians and 10 nurses from department of burn surgery and 5 physicians and 10 nurses from department of intensive care medicine in each group. Each group of physicians and nurses were responsible for treatment of 5 patients. Treatment of patients was leaded by surgeons from department of burn surgery, who were responsible for wound dealing and operation. Physicians from department of intensive care medicine were responsible for systemic treatment and adjustment of relevant equipment's parameters. Volume of fluid infusion and urine output in shock period, severe systemic complication during period of treatment, using time and kind of antibiotics, death in 1 month after admission, length of hospital stay, and survival of patients were monitored. Results: Volume of fluid infusion of 15 extremely severe burn patients within the first 24 hours post injury was 10 360-17 162 (12 998±1 811) mL, including (1.62±0.23) mL·% total body surface area (TBSA)^-1·kg^-1 electrolyte and colloid and (2 850±232) mL glucose, with electrolyte and colloid ratio of (1.76±0.23)∶1.00. Volume of urine output within the first 24 hours post injury was (2 384±1 242) mL, with (99±52) mL in each hour. Volume of fluid infusion of 15 extremely severe burn patients within the second 24 hours post injury was 8 720-11 616 (9 406±1 277) mL, including (1.04±0.22) mL·%TBSA^-1·kg^-1 electrolyte and colloid and (2 910±187) mL glucose, with electrolyte and colloid ratio of (1.53±0.31)∶1.00. Volume of urine output within the second 24 hours post injury of patients was (2 299±1 362) mL , with (108±61) mL in each hour. One patient had pulmonary infection, and 7 patients had fungal infection, and no patient had gut microbiota dysbiosis. Patients were treated with combined 2 kinds of antibiotics for 21-85 (50±16) d. No patient died within 1 month after admission. The length of hospital stay was 53-132 (98±44) d. Ten patients survived finally. Conclusions After being treated by cooperation between physicians in department of burn surgery and department of intensive care medicine, severe mass burn patients involved in August 2nd Kunshan factory aluminum dust explosion accident had hemodynamic stability and could stably experience shock period, with less complication, shorter length of hospital stay, no death within 1 month after admission, more survived patients, which can provide reference for rescue and treatment of severe mass burn patients.