[Effect and mechanism of human adipose-derived stem cell exosomes on diabetic peripheral neuropathy].

Objective: To investigate the changes of artemin protein expression in diabetic peripheral neuropathy (DPN) and to explore the regulatory effect of human adipose-derived stem cell (ADSC) exosomes on the change of artemin protein expression. Methods: This research was a prospective observational clinical research combined with experimental research. Thirteen DPN patients (9 males and 4 females, aged 32 to 68 years) who were admitted to the First Affiliated Hospital of Air Force Medical University (hereinafter referred to as our hospital) from May 2022 to October 2023 and met the inclusion criteria were selected as DPN group, and 5 non-diabetes patients (4 males and 1 female, aged 29 to 61 years) who were admitted to our hospital in the same period of time and met the inclusion criteria were selected as control group. The toe nerve or sural nerve tissue in the abandoned tissue after debridement or amputation of patients in the two groups was collected. The pathological changes of nerve tissue were observed after hematoxylin-eosin staining; the protein expressions of S100ß and artemin in nerve tissue were observed after immunofluorescence staining, and the artemin protein expression was quantified; the protein and mRNA expressions of artemin were detected by Western blotting and real-time fluorescent quantitative reverse transcription polymerase chain reaction, respectively (the sample number in DPN group and control group was 13 and 5, respectively). Twelve male C57BL/6 mice aged 3 to 5 days were collected to isolate Schwann cells, and the cells were divided into conventional culture group cultured routinely, high glucose alone group (cultured with high concentration of glucose solution only), and high glucose+exosome group (cultured with high concentration of glucose solution and extracted human ADSC exosomes). After 24 hours of culture, the cell proliferation activity was detected by cell counting kit 8 (n=6). After 48 hours of culture, the protein expression of artemin was detected by Western blotting (n=3). Results: Compared with those in control group, the neural supporting cells decreased and the inflammatory cells increased in the nerve tissue of patients in DPN group, showing typical manifestations of nerve injury. Immunofluorescence staining showed that compared with those in control group, the nuclei was more, and the protein expression of S100ß was lower in nerve tissue of patients in DPN group. The protein expression of artemin in nerve tissue of patients in DPN group was 71±31, which was significantly lower than 1 729±62 in control group (t=76.92, P<0.05). Western blotting detection showed that the protein expression of artemin in nerve tissue of patients in DPN group was 0.74±0.08, which was significantly lower than 0.97±0.06 in control group (t=5.49, P<0.05). The artemin mRNA expression in nerve tissue of patients in DPN group was significantly lower than that in control group (t=7.65, P<0.05). After 24 hours of culture, compared with that in conventional culture group, the proliferation activities of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased (P<0.05); compared with that in high glucose alone group, the proliferation activity of Schwann cells in high glucose+exosome group was significantly increased (P<0.05). After 48 hours of culture, compared with those in conventional culture group, the protein expressions of artemin of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased (P<0.05); compared with that in high glucose alone group, the protein expression of artemin of Schwann cells in high glucose+exosome group was significantly increased (P<0.05). Conclusions: The protein expression of artemin in nerve tissue of DPN patients is lower than that in normal nerve tissue, which may be related to the reduction of proliferation activity of Schwann cells by high glucose. Human ADSC exosomes may improve the proliferation activity of Schwann cells by increasing artemin protein expression, thereby delaying the progression of DPN.

[Research advances on the role of Schwann cells in diabetic peripheral neuropathy].

Diabetic peripheral neuropathy (DPN) is one of the common chronic complications of diabetes, resulting in neuropathy of spinal nerve, cranial nerve, and vegetative nerve. Diabetic distal symmetric multiple neuropathy is the most representative lesion of DPN, including symptoms of bilateral limbs pain, numbness, and paresthesia, etc. DPN is one of the main reasons causing diabetic foot ulcer (DFU). Schwann cells (SCs) are the primary glia cells of the peripheral nervous system, which play very important role in repairing after nerve injury. As the target cells of chronic hyperglycemia, SCs' functions, including the formation of myelin sheath, the secretion of neurotrophic factors, energy supplying for the axon, and the guidance of axon regeneration, etc., are damaged under the action of high glucose. The destroyed functions of SCs can inhibit the repair of damaged nerves and accelerate the progress of DPN. Therefore, if the damage of high glucose to SCs can be effectively reduced, it will provide a new way for the treatment of DPN and DFU and reduce the morbidity of DFU. This review focuses on the function of SCs and its relationship with DPN.

[A prospective randomized controlled study of antibiotic bone cement in the treatment of diabetic foot ulcer].

Objective: To investigate the clinical effects and related mechanism of antibiotic bone cement in treating diabetic foot ulcer (DFU). Methods: A prospective randomized controlled study was conducted. From August 2020 to August 2022, 24 patients with DFU who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University. According to the block randomization, the patients were divided into 2 groups, with 12 patients in each group. In antibiotic bone cement group, there were 7 male and 5 female patients, aged (64±8) years, with the ulcer area of (41±21) cm2. In silver sulfadiazine group, there were 8 male and 4 female patients, aged (62±8) years, with the ulcer area of (38±19) cm2. Under the condition of ensuring the patency of at least one main inferior genicular artery in each patient, the continuous vacuum sealing drainage was performed for 3-5 days after thorough debridement. Thereafter, the wounds in antibiotic bone cement group were treated with gentamicin-laden bone cement, and the wounds in silver sulfadiazine group were treated with silver sulfadiazine cream for dressing change. After 3 weeks of dressing change, the wound was covered with split-thickness skin graft from the lateral thigh on the affected side. Before debridement and after 3 weeks of dressing change, the blood flow intensities of wound tissue and normal skin tissue in foot were measured using laser Doppler flowmeter, and then, the percentage of relative blood flow intensity of wound and the change rate of blood flow intensity were calculated. After 3 weeks of dressing change, the wound margin tissue was taken, the number of CD31-positive neovascular and the vascular morphology were observed and detected by immunohistochemical staining, the morphology of blood vessels surrounded by CD31 and α-smooth muscle actin (α-SMA) double-positive cells was observed by immunofluorescence staining, the cell proliferation activity was evaluated by immunofluorescence staining (denoted as the ratio of Ki67 positive cells), and the protein expression of vascular endothelial growth factor receptor 2 (VEGFR2) was detected by Western blotting. The skin graft survival was observed 3-5 days after skin grafting, and the wound healing time was recorded. Data were statistically analyzed with independent sample t test and Fisher's exact probability test. Results: The percentages of relative blood flow intensity of wounds of patients before debridement were similar between the two groups (P>0.05). After 3 weeks of dressing change, the percentage of relative blood flow intensity of wounds and the change rate of blood flow intensity of patients in antibiotic bone cement group were (44.7±2.0)% and (129±12)%, respectively, which were significantly higher than (28.3±1.2)% and (41±8)% in silver sulfadiazine group (with t values of 24.15 and 20.97, respectively, P<0.05). After 3 weeks of dressing change, compared with those in silver sulfadiazine group, the number of CD31-positive neovascular in the wound margin tissue of patients in antibiotic bone cement group was significantly increased (t=33.81, P<0.05) with larger diameter and more regular arrangement, the vascular wall continuity surrounded by CD31 and α-SMA double-positive cells was better, and the ratio of Ki67 positive cells and protein expression of VEGFR2 were significantly increased (with t values of 40.97 and 47.38, respectively, P<0.05). On post skin grafting day 3-5, all the patients in antibiotic bone cement group and 8 patients in silver sulfadiazine group had good skin graft survival, while 4 patients in silver sulfadiazine group showed spotted/patchy skin graft necrosis, which were cured after corresponding treatment. The wound healing time of patients in antibiotic bone cement group was (47.1±2.9) d, which was significantly shorter than (58.8±2.3) d in silver sulfadiazine group (t=10.86, P<0.05). Conclusions: Compared with silver sulfadiazine, clinical application of antibiotic bone cement for treating DFU has the characteristics of accelerating wound healing and better reconstruction of local blood flow, which may be closely related to the fact that antibiotic bone cement promoted the local angiogenesis effectively in the wound through enhancing the expression of VEGFR2.

[Effects of the anterolateral thigh chimeric perforator flaps in repairing complex wounds of foot and ankle].

Objective: To investigate the effects of anterolateral thigh chimeric perforator flap in repairing complex wounds of foot and ankle. Methods: A retrospective observational study was conducted. From May 2018 to June 2022, 23 patients who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University to repair complex wounds of foot and ankle with anterolateral thigh chimeric perforator flaps, including 15 males and 8 females, aged from 20 to 66 years. The wounds were all accompanied by bone exposure and defects, and were complicated with varying degrees of infection. All patients underwent debridement and continuous vacuum sealing drainage treatment for 1 week in stage Ⅰ, with the skin and soft tissue defect area after debridement being 10 cm×5 cm to 22 cm×7 cm. In stage Ⅱ, the anterolateral thigh chimeric perforator flap was used to cover the defective wound, of which the muscle flap was used to fill the deep invalid cavity of the ankle joint or cover bone and internal fixation exposures, and the skin flap was used to cover the superficial wound, with the area of the skin flap ranging from 11 cm×6 cm to 23 cm×8 cm, and the area of the muscle flap ranging from 4.0 cm×2.5 cm to 8.0 cm×5.0 cm. The survival of the flap was observed after operation. During follow-up, the color, texture, appearance, and complications of the flap were observed, the function of ankle joint and its range of dorsiflexion motion and plantar flexion motion were measured, and the scar hyperplasia and muscular hernia in donor area were observed. Results: Ecchymosis and epidermal necrosis occurred at the tip of the flap in 1 patient on 5 days after operation and healed after dressing change for 1 week; the other flaps of patients survived successfully. After 6 to 40 months of follow-up, the color, texture, and shape of flaps were good, but 1 patient was not satisfied with the shape of the flap because of flap swelling; the ankle joint movement was basically normal, the dorsiflexion motion was 15-30°, and the plantar flexion motion was 20-45°; the scar hyperplasia in the donor area of the flap was not obvious, and no muscular hernia occurred. Conclusions: The anterolateral thigh chimeric perforator flap can effectively fill the deep invalid cavity of ankle joint and cover the superficial wound at the same time, with minimal damage to the donor site. So it is an ideal flap for repairing the complex wounds of foot and ankle.

[Safety and efficacy of laparoscopic surgery in locally advanced gastric cancer patients with neoadjuvant chemotherapy combined with immunotherapy].

Objective: To investigate the safety and efficacy of laparoscopic surgery in locally advanced gastric cancer patients with neoadjuvant SOX chemotherapy combined with PD-1 inhibitor immunotherapy. Methods: Between November 2020 and April 2021, patients with locally advanced gastric cancer who were admitted to the Union Hospital of Tongji Medical College of Huazhong University of Science and Technology were prospectively enrolled in this study. Inclusion criteria were: (1) patients who signed the informed consent form voluntarily before participating in the study; (2) age ranging from 18 to 75 years; (3) patients staged preoperatively as cT3-4N+M0 by the TNM staging system; (4) Eastern Collaborative Oncology Group score of 0-1; (5) estimated survival of more than 6 months, with the possibility of performing R0 resection for curative purposes; (6) sufficient organ and bone marrow function within 7 days before enrollment; and (7) complete gastric D2 radical surgery. Exclusion criteria were: (1) history of anti-PD-1 or PD-L1 antibody therapy and chemotherapy; (2) treatment with corticosteroids or other immunosuppre- ssants within 14 days before enrollment; (3) active period of autoimmune disease or interstitial pneumonia; (4) history of other malignant tumors; (5) surgery performed within 28 days before enrollment; and (6) allergy to the drug ingredients of the study. Follow-up was conducted by outpatient and telephone methods. During preoperative SOX chemotherapy combined with PD-1 inhibitor immunotherapy, follow-up was conducted every 3 weeks to understand the occurrence of adverse reactions of the patients; follow-up was conducted once after 1 month of surgical treatment to understand the adverse reactions and survival of patients. Observation indicators were: (1) condition of enrolled patients; (2) reassessment after preoperative therapy and operation received (3) postoperative conditions and pathological results. Evaluation criteria were: (1) tumor staged according to the 8th edition of the American Joint Committee on Cancer (AJCC) TNM staging system; (2) tumor regression grading (TRG) of pathological results were evaluated with reference to AJCC standards; (3) treatment-related adverse reactions were evaluated according to version 5.0 of the Common Terminology Criteria for Adverse Events; (4) tumor response was evaluated by CT before and after treatment with RECIST V1.1 criteria; and (5) Clavien-Dindo complication grading system was used for postoperative complications assessment. Results: A total of 30 eligible patients were included. There were 25 males and 5 females with a median age of 60.5 (35-74) years. The primary tumor was located in the gastroesophageal junction in 12 cases, in the upper stomach in 8, in the middle stomach in 7, and in the lower stomach in 3. The preoperative clinical stage of 30 cases was III. Twenty-one patients experienced adverse reactions during neoadjuvant chemotherapy combined with immunotherapy, including four cases of CTCAE grade 3-4 adverse reactions resulting in bone marrow suppression and thoracic aortic thrombosis. All cases of adverse reactions were alleviated or disappeared after active symptomatic treatment. Among the 30 patients who underwent surgery, the time from chemotherapy combined with immunotherapy to surgery was 28 (23-49) days. All 30 patients underwent laparoscopic radical gastrectomy, of which 20 patients underwent laparoscopic-assisted radical gastric cancer resection; 10 patients underwent total gastrectomy for gastric cancer, combined with splenectomy in 1 case and cholecystectomy in 1 case. The surgery time was (239.9±67.0) min, intraoperative blood loss was 84 (10-400) ml, and the length of the incision was 7 (3-12) cm. The degree of adenocarcinoma was poorly differentiated in 18 cases, moderately differentiated in 12 cases, nerve invasion in 11 cases, and vascular invasion in 6 cases. The number lymph nodes that underwent dissection was 30 (17-58). The first of gas passage, the first postoperative defecation time, the postoperative liquid diet time, and the postoperative hospitalization time of 30 patients was 3 (2-6) d, 3 (2-13) d, 5 (3-12) d, and 10 (7-27) d, respectively. Postoperative complications occurred in 23 of 30 patients, including 7 cases of complications of Clavien-Dindo grade IIIa or above. Six patients improved after treatment and were discharged from hospital, while 1 patient died 27 days after surgery due to granulocyte deficiency, anemia, bilateral lung infection, and respiratory distress syndrome. The remaining 29 patients had no surgery-related morbidity or mortality within 30 days of discharge. Postoperative pathological examination showed TRG grades 0, 1, 2, and 3 in 8, 9, 4, and 9 cases, respectively, and the number of postoperative pathological TNM stages 0, I, II, and III was 8, 7, 8, and 7 cases, respectively. The pCR rate was 25.0% (8/32). Conclusion: Laparoscopic surgery after neoadjuvant SOX chemotherapy combined with PD-1 inhibitor immunotherapy for locally advanced gastric cancer is safe and feasible, with satisfactory short-term efficacy. Early detection and timely treatment of related complications are important.

[Effects of exosomes from hepatocyte growth factor-modified human adipose mesenchymal stem cells on full-thickness skin defect in diabetic mice].

Objective: To investigate the effects and mechanism of exosomes from hepatocyte growth factor (HGF)-modified human adipose mesenchymal stem cells (ADSCs) on full-thickness skin defect wounds in diabetic mice. Methods: The experimental study method was adopted. Discarded adipose tissue of 3 healthy females (10-25 years old) who underwent abdominal surgery in the Department of Plastic Surgery of First Affiliated Hospital of Air Force Medical University from February to May 2021 was collected, and primary ADSCs were obtained by collagenase digestion method and cultured for 7 days. Cell morphology was observed by inverted phase contrast microscope. The ADSCs of third passage were transfected with HGF lentivirus and cultured for 5 days, and then the fluorescence of cells was observed by imaging system and the transfection rate was calculated. The exosomes of ADSCs of the third to sixth passages and the HGF transfected ADSCs of the third to sixth passages were extracted by density gradient centrifugation, respectively, and named, ADSC exosomes and HGF-ADSC exosomes. The microscopic morphology of exosomes was observed by transmission electron microscopy, and the positive expressions of CD9, CD63, and CD81 of exosomes were detected by flow cytometry, respectively. Twenty-four 6-week-old male Kunming mice were selected to make the diabetic models, and full-thickness skin defect wounds were made on the backs of mice. According to the random number table method, the mice were divided into phosphate buffer solution (PBS) group, HGF alone group, ADSC exosome alone group, and HGF-ADSC exosome group, with 6 mice in each group, and treated accordingly. On post injury day (PID) 3, 7, 10, and 14, the wounds were observed and the wound healing rate was calculated; the blood flow intensity of wound base was detected by Doppler flowmeter and the ratio of relative blood flow intensity on PID 10 was calculated. On PID 10, the number of Ki67 positive cells in wounds was detected by immunofluorescence method, and the number of new-vascularity of CD31 positive staining and tubular neovascularization in the wounds was detected by immunohistochemistry method; the protein expressions of protein endothelial nitric oxide synthase (eNOS), phosphatidylinositol 3-kinase (PI3K), phosphorylated PI3K (p-PI3K), protein kinase B (Akt) and phosphorylated Akt (p-Akt) in wounds were detected by Western blotting, and the ratios of p-PI3K to PI3K and p-Akt to Akt were calculated. On PID 14, the defect length and collagen regeneration of wound skin tissue were detected by hematoxylin and eosin staining and Masson staining, respectively, and the collagen volume fraction (CVF) was calculated. The number of samples is 3 in all cases. Data were statistically analyzed with repeated measurement analysis of variance, one-way analysis of variance, and Tukey test. Results: After 7 days of culture, the primary ADSCs were spindle shaped and arranged in vortex shape after dense growth. After 5 days of culture, HGF transfected ADSCs of the third passage carried green fluorescence, and the transfection rate was 85%. The ADSC exosomes and HGF-ADSC exosomes were similar in microscopic morphology, showing vesicular structures with an average particle size of 103 nm and 98 nm respectively, and both were CD9, CD63, and CD81 positive. On PID 3, the wounds of mice in the 4 groups were all red and swollen, with a small amount of exudate. On PID 7, the wounds of HGF-ADSC exosome group were gradually reduced, while the wounds of the other three groups were not significantly reduced. On PID 10, the wounds in the 4 groups were all reduced and scabbed. On PID 14, the wounds in HGF-ADSC exosome group were basically healed, while the residual wounds were found in the other three groups. On PID 3, the healing rates of wounds in the four groups were similar (P>0.05); On PID 7 and 10, the wound healing rates in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 13.11, 13.11, 11.89, 12.85, 11.28, and 7.74, respectively, all P<0.01); on PID 14, the wound healing rate in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 15.50, 11.64, and 6.36, respectively, all P<0.01). On PID 3, there was no obvious blood supply in wound base of mice in the 4 groups. On PID 7, microvessels began to form in the wound base of HGF-ADSC exosome group, while the wound base of the other three groups was only congested at the wound edge. On PID 10, microvessel formation in wound base was observed in the other 3 groups except in PBS group, which had no obvious blood supply. On PID 14, the blood flow intensity of wound base in HGF-ADSC exosome group was stronger than that in the other 3 groups, and the distribution was uniform. On PID 10, the ratio of wound base relative blood flow intensity in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 23.73, 19.32, and 9.48, respectively, all P<0.01); The numbers of Ki67-positive cells and new-vascularity of wounds in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 19.58, 18.20, 11.04, 20.68, 13.79, and 8.12, respectively, P<0.01). On PID 10, the protein expression level of eNOS of wounds in HGF-ADSC exosome group was higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 53.23, 42.54, and 26.54, respectively, all P<0.01); the ratio of p-PI3K to PI3K and the ratio of p-Akt to Akt of wounds in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 16.11, 11.78, 6.08, 65.54, 31.63, and 37.86, respectively, P<0.01). On PID 14, the length of skin tissue defect in the wounds of HGF-ADSC exosome group was shorter than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 20.51, 18.50, and 11.99, respectively, all P<0.01); the CVF of wounds in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group and ADSC exosome alone group (with q values of 31.31, 28.52, and 12.35, respectively, all P<0.01). Conclusions: Human HGF-ADSC exosomes can significantly promote wound healing in diabetic mice by increasing neovascularization in wound tissue, and the mechanism may be related to the increased expression of eNOS in wounds by activating PI3K/Akt signaling pathway.

[Techniques in prophylactic ileostomy reversal].

In order to prevent and reduce the severity of anastomotic leakage after low rectal cancer surgery, prophylactic ileostomy is often performed by the clinician simultaneously. There are many controversies about prophylactic ileostomy in medicine, such as ileostomy indications, ileostomy complications, ileostomy reversal time, ileostomy reversal method and technique. Based on relevant literature and our own experience, we discussed the timing, method and complications of ileostomy reversal in this article to improve the diagnosis and treatment of ileostomy reversal as well as the life quality of the patients after ileostomy reversal.

[Clinical effects of free transplantation of expanded thoracodorsal artery perforator flaps in reconstructing cervical cicatrix contracture deformity after burns].

Objective: To explore the clinical effects of free transplantation of expanded thoracodorsal artery perforator flaps in reconstructing cervical cicatrix contracture deformity after burns. Methods: A retrospective observational study was conducted. From May 2018 to April 2021, 11 patients with cervical cicatrix contracture deformity after burns who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University, including 3 males and 8 females, aged 5 to 46 years, with a course of cervical cicatrix contracture deformity of 5 months to 8 years. The degree of cervical cicatrix contracture deformity was degree Ⅰ in one patient, degree Ⅱ in nine patients, and degree Ⅲ in one patient. In the first stage, according to the sizes of neck scars, one rectangular skin and soft tissue expander (hereinafter referred to as expander) with rated capacity of 200 to 600 mL was placed in the back. The expansion time was 4 to 12 months with the total normal saline injection volume being 3.0 to 3.5 times of the rated capacity of expander. In the second stage, free expanded thoracodorsal artery perforator flaps with areas of 10 cm×7 cm to 24 cm×13 cm were cut out to repair the wounds with areas of 9 cm×6 cm to 23 cm×12 cm which was formed after cervical cicatectomy. The main trunk of thoracodorsal artery and vein were selected for end-to-end anastomosis with facial artery and vein, and the donor sites were directly closed. The survival of flaps and healing of flap donor sites were observed on the 14th day post surgery. The appearances and cicatrix contracture deformity of the flaps, recovery of cervical function, and scar hyperplasia of donor sites were followed up. Results: On the 14th day post surgery, the flaps of ten patients survived, while ecchymosis and epidermal necrosis occurred in the center of flap of one patient and healed 2 weeks after dressing change. On the 14th day post surgery, the flap donor sites of 11 patients all healed well. During the follow-up of 6-12 months post surgery, the flaps of ten patients were similar to the skin around the recipient site in texture and color, while the flap of one patient was slightly swollen. All of the 11 patients had good recovery of cervical function and no obvious scar hyperplasia nor contracture in the flaps or at the donor sites. Conclusions: Application of expanded thoracodorsal artery perforator flaps can restore the appearance and function of the neck, and cause little damage to the donor site in reconstructing the cervical cicatrix contracture deformity after burns, which is worthy of clinical reference and application.

[Effects of exosomes from human adipose-derived mesenchymal stem cells on pulmonary vascular endothelial cells injury in septic mice and its mechanism].

Objective: To investigate the effects of exosomes from human adipose-derived mesenchymal stem cells (ADSCs) on pulmonary vascular endothelial cells (PMVECs) injury in septic mice and its mechanism. Methods: The experimental research method was adopted. The primary ADSCs were isolated and cultured from the discarded fresh adipose tissue of 3 patients (female, 10-25 years old), who were admitted to the First Affiliated Hospital of Air Force Medical University undergoing abdominal surgery, and the cell morphology was observed by inverted phase contrast microscope on the 5th day. The expressions of CD29, CD34, CD44, CD45, CD73, and CD90 of ADSCs in the third passage were detected by flow cytometry. The third to the fifth passage of ADSCs were collected, and their exosomes from the cell supernatant were obtained by differential ultracentrifugation, and the shape, particle size, and the protein expressions of CD9, CD63, tumor susceptibility gene 101 (TSG101), and ß-actin of exosomes were detected, respectively, by transmission electron microscopy, nano-particle tracking analysis and Western blotting. Twenty-four adult male BALB/c mice were adopted and were divided into normal control group, caecal ligation perforation (CLP) alone group, and CLP+ADSC-exosome group with each group of 8 according to random number table (the same grouping method below) and were treated accordingly. At 24 h after operation, tumor necrosis factor (TNF-α) and interleukin 1ß (IL-1ß) levels of mice serum were detected by enzyme-linked immunosorbent assay, and lung tissue morphology of mice was detected by hematoxylin-eosin and myeloperoxidase staining, and the expression of 8-hydroxy-deoxyguanosine (8-OHdG) of mouse lung cells was detected by immunofluorescence method. Primary PMVECs were obtained from 1-month-old C57 mice regardless gender by tissue block method. The expression of CD31 of PMVECs was detected by immunofluorescence and flow cytometry. The third passage of PMVECs was co-cultured with ADSCs derived exosomes for 12 h, and the phagocytosis of exosomes by PMVECs was detected by PKH26 kit. The third passage of PMVECs were adopted and were divided into blank control group, macrophage supernatant alone group, and macrophage supernatant+ADSC-exosome group, with 3 wells in each group, which were treated accordingly. After 24 h, the content of reactive oxygen species in cells was detected by flow cytometry, the expression of 8-OHdG in cells was detected by immunofluorescence, and Transwell assay was used to determine the permeability of cell monolayer. The number of samples in above were all 3. Data were statistically analyzed with one-way analysis of variance and least significant difference t test. Results: The primary ADSCs were isolated and cultured to day 5, growing densely in a spindle shape with a typical swirl-like. The percentages of CD29, CD44, CD73 and CD90 positive cells of ADSCs in the third passage were all >90%, and the percentages of CD34 and CD45 positive cells were <5%. Exosomes derived from ADSCs of the third to fifth passages showed a typical double-cavity disc-like structure with an average particle size of 103 nm, and the protein expressions of CD9, CD63 and TSG101 of exosomes were positive, while the protein expression of ß-actin of exosomes was negative. At 24 h after operation, compared with those in normal control group, both the levels of TNF-α and IL-1ß of mice serum in CLP alone group were significantly increased (with t values of 28.76 and 29.69, respectively, P<0.01); compared with those in CLP alone group, both the content of TNF-α and IL-1ß of mice serum in CLP+ADSC-exosome group was significantly decreased (with t values of 9.90 and 4.76, respectively, P<0.05 or P<0.01). At 24 h after surgery, the pulmonary tissue structure of mice in normal control group was clear and complete without inflammatory cell infiltration; compared with those in normal control group, the pulmonary tissue edema and inflammatory cell infiltration of mice in CLP alone group were more obvious; compared with those in CLP alone group, the pulmonary tissue edema and inflammatory cell infiltration of mice in CLP+ADSC-exosome group were significantly reduced. At 24 h after operation, endothelial cells in lung tissues of mice in 3 groups showed positive expression of CD31; compared with that in normal control group, the fluorescence intensity of 8-OHdG positive cells of the lung tissues of mice in CLP alone group was significantly increased, and compared with that in CLP alone group, the fluorescence intensity of 8-OHdG positive cells in the lung tissues of mice in CLP+ADSC-exosome group was significantly decreased. The PMVECs in the 3rd passage showed CD31 positive expression by immunofluorescence, and the result of flow cytometry showed that CD31 positive cells accounted for 99.5%. At 12 h after co-culture, ADSC-derived exosomes were successfully phagocytose by PMVECs and entered its cytoplasm. At 12 h after culture of the third passage of PMVECs, compared with that in blank control group, the fluorescence intensity of reactive oxygen species of PMVECs in macrophage supernatant alone group was significantly increased (t=15.73, P<0.01); compared with that in macrophage supernatant alone group, the fluorescence intensity of reactive oxygen species of PMVECs in macrophage supernatant+ADSC-exosome group was significantly decreased (t=4.72, P<0.01). At 12 h after culture of the third passage of PMVECs, and the 8-OHdG positive fluorescence intensity of PMVECs in macrophage supernatant alone group was significantly increased; and compared with that in blank control group, the 8-OHdG positive fluorescence intensity of PMVECs in macrophage+ADSC-exosome supernatant group was between blank control group and macrophage supernatant alone group. At 12 h after culture of the third passage PMVECs, compared with that in blank control group, the permeability of PMVECs monolayer in macrophage supernatant alone group was significantly increased (t=6.34, P<0.01); compared with that in macrophage supernatant alone group, the permeability of PMVECs monolayer cells in macrophage supernatant+ADSC-exosome group was significantly decreased (t=2.93, P<0.05). Conclusions: Exosomes derived from ADSCs can ameliorate oxidative damage in mouse lung tissue, decrease the level of reactive oxygen species, 8-OHdG expression, and permeability of PMVECs induced by macrophage supernatant.

[Multicenter real-world study on safety and efficacy of neoadjuvant therapy in combination with immunotherapy for colorectal cancer].

Objective: To provide reference and evidence for clinical application of neoadjuvant immunotherapy in patients with colorectal cancer through multicenter large-scale analysis based on real-world data in China. Methods: This was a retrospective multicenter case series study. From January 2017 to October 2021, data of 94 patients with colorectal cancer who received neoadjuvant immunotherapy in Peking University Cancer Hospital (55 cases), Union Hospital of Tongji Medical College of Huazhong University of Science and Technology (19 cases), Sun Yat-sen University Cancer Center (13 cases) and Changhai Hospital of Navy Medical University (7 cases) were retrospectively collected, including 48 males and 46 females. The median age was 58 years. Eighty-one cases were rectal cancer and 13 cases were colon cancer (2 cases of double primary colon cancer). Twelve cases were TNM staging II and 82 cases were stage III. Forty-six cases were well differentiated, 37 cases were moderately differentiated and 11 cases were poorly differentiated. Twenty-six patients (27.7%) with mismatch repair defects (dMMR) and microsatellite instability (MSI-H) were treated with immunotherapy alone, mainly programmed cell death protein-1 (PD-1); sixty-eight cases (72.3%) with mismatch repair proficient (pMMR) and microsatellite stability (MSS) were treated with immune combined with neoadjuvant therapy, mainly CapeOx (capecitabine+oxaliplatin) combined with PD-1 antibody plus long- or short-course radiotherapy, or PD-1 antibody combined with cytotoxic T lymphocyte associated antigen 4 (CTLA-4) antibody. Analysis and evaluation of adverse events during neoadjuvant immunotherapy were performed according to the National Cancer Institute Common Toxicity Standard version 3.0; the surgical complications were evaluated according to the Clavien-Dindo grading standard; the efficacy evaluation of neoadjuvant immunotherapy included the following indicators: major pathological remission (MPR) was defined as tumor regression induced by neoadjuvant therapy in pathology residual tumor ≤10%; pathological complete response (pCR) was defined as tumor regression induced by neoadjuvant therapy without residual tumor in pathology; the tumor response rate was disease control rate (DCR), namely the proportion of complete response (CR), partial response (PR) and stable disease (SD) in the whole group; the objective response rate (ORR) was CR+PR. Results: The median cycle of neoadjuvant immunotherapy was 4 (1-10) in whole group, and the incidence of immune-related adverse reactions was 37.2% (35/94), including 35 cases (37.2%) of skin-related adverse reactions, 21 cases (22.3%) of thyroid dysfunction and 8 cases (8.5%) of immune enteritis, of which grade III or above accounted for 1.1%. The median interval between completion of neoadjuvant therapy and surgery was 30 (21-55) days. There were 81 cases of radical resection of rectal cancer, 11 cases of radical resection of colon cancer, and 2 cases of colon cancer combined with other organ resection. The primary tumor resection of all the patients reached R0. The incidence of surgical-related complications was 22.3% (21/94), mainly anastomotic leakage (4 cases), pelvic infection (4 cases), abdominal effusion (3 cases), anastomotic stenosis (3 cases ) and abdominal and pelvic hemorrhage (2 cases). Grade I-II complications developed in 13 cases (13.8%), grade III and above complications developed in 8 cases (8.5%), no grade IV or above complications were found. During a median follow-up of 32 (1-46 ) months, DCR was 98.9% (93/94), ORR was 88.3 % (83/94), pCR was 41.5% (39/94), MPR was 60.6% (57/94). The pCR rate of 26 patients with dMMR and MSI-H undergoing simple immunotherapy was 57.7% (15/26), and MPR rate was 65.4% (17/26). The pCR rate of 68 pMMR and MSS patients undergoing combined immunotherapy was 35.3%(24/68), and MPR rate was 58.8% (40/68). Conclusions: Neoadjuvant immunotherapy has favorable tumor control rate and pathological remission rate for patients with initial resectable colorectal cancer. The incidences of perioperative adverse reactions and surgical complications are acceptable.

[Safety evaluation of hyperthermic intraperitoneal chemotherapy in patients with local advanced gastric cancer after radical resection for prevention of peritoneal metastasis].

Objective: Patients with advanced gastric cancer have a poor prognosis and a possibility of peritoneal metastasis even if receiving gastrectomy. Hyperthermic intraperitoneal chemotherapy (HIPEC) can effectively kill free cancer cells or small lesions in the abdominal cavity. At present, preventive HIPEC still lacks safety evaluation in patients with locally advanced gastric cancer. This study aims to explore the safety of radical resection combined with HIPEC in patients with locally advanced gastric cancer. Methods: A descriptive case series study was carried out. Clinicopathological data of 130 patients with locally advanced gastric cancer who underwent radical resection + HIPEC at the Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2020 to February 2021 were retrospectively analyzed. Inclusion criteria: (1) locally advanced gastric adenocarcinoma confirmed by postoperative pathology; (2) no distant metastasis was found before surgery; (3) radical resection; (4) at least one HIPEC treatment was performed. Exclusion criteria: (1) incomplete clinicopathological data; (2) tumor metastasis was found during operation; (3) concomitant with other tumors. HIPEC method: all the patients received the first HIPEC immediately after D2 radical resection, and returned to the ward after waking up from anesthesia; the second and the third HIPEC were carried out according to the patient's postoperative recovery and tolerance; interval between two HIPEC treatments was 48 h. Observation indicators: (1) basic information, including gender, age, body mass index, etc.; (2) treatment status; (3) perioperative adverse events: based on the standard of common adverse events published by the US Department of Health and Public Health (CTCAE 5.0), the adverse events of grade 2 and above during the treatment period were recorded, including hypoalbuminemia, bone marrow cell reduction, wound complications, abdominal infection, lung infection, gastroparesis, anemia, postoperative bleeding, anastomotic leakage, intestinal obstruction, pleural effusion, abdominal distension, impaired liver function, and finally a senior professional title chief physician reviewed the above adverse events and made a safety evaluation of the patient; (4) association between times of HIPEC treatment and adverse events in perioperative period; (5) analysis of risk factors for adverse events in perioperative period. Results: Among the 130 patients, 79 were males and 51 were females with a median age of 59 (54, 66) years and an average body mass index of (23.9±7.4) kg/m(2). The tumor size was (5.4±3.0) cm and 100 patients (76.9%) had nerve invasion. All the 130 patients received radical resection + HIPEC and 125 (96.2%) patients underwent laparoscopic surgery. The mean operative time was (345.6±52.3) min and intraoperative blood loss was (82.0±36.5) ml. One HIPEC treatment was performed in 54 patients (41.5%), 2 HIPEC treatments were in 57 (43.8%), and 3 HIPEC treatments were in 19 (14.6%). The average postoperative hospital stay was (13.1±7.5) d. A total of 57 patients (43.8%) had 71 cases of postoperative complications of different degrees. Among them, the incidence of hypoalbuminemia was 22.3% (29/130), and the grade 2 and above anemia was 15.4% (20/130), lung infection was 3.8% (5/130), bone marrow cell suppression was 3.7% (4/130), abdominal cavity infection was 2.3% (3/130), and liver damage was 2.3% (3/130), wound complications was 1.5% (2/130), abdominal distension was 1.5% (2/130), anastomotic leakage was 0.8% (1/130), gastroparesis was 0.8% (1/130) and intestinal obstruction was 0.8% (1/130), etc. These adverse events were all improved by conservative treatments. There were no statistically significant differences in the incidence of adverse events during the perioperative period among patients undergoing 1, 2, and 3 times of HIPEC treatments (all P>0.05). Univariate and multivariate logistic analyses showed that age > 60 years (OR: 2.346, 95%CI: 1.069-5.150, P=0.034) and neurological invasion (OR: 2.992, 95%CI: 1.050-8.523, P=0.040) were independent risk factors for adverse events in locally advanced gastric cancer patients undergoing radical resection+HIPEC (both P<0.05). Conclusions: Radical surgery + HIPEC does not significantly increase the incidence of perioperative complications in patients with advanced gastric cancer. The age >60 years and nerve invasion are independent risk factors for adverse events in these patients.

[Diagnosis and treatment status of perioperative anemia in patients with gastrointestinal neoplasms: a multi-center study in Hubei Province].

Objective: To investigate the incidence and treatment of perioperative anemia in patients with gastrointestinal neoplasms in Hubei Province. Methods: The clinicopathological data of 7 474 patients with gastrointestinal neoplasms in 62 hospitals in 15 cities (state) of Hubei Province in 2019 were collected in the form of network database. There were 4 749 males and 2 725 females. The median age of the patients was 62 years (range: 17 to 96 years). The hemoglobin value of the first time in hospital and the first day after operation was used as the criterion of preoperative anemia and postoperative anemia. Anemia was defined as male hemoglobin <120 g/L and female hemoglobin <110.0 g/L, mild anemia as 90 to normal, moderate anemia as 60 to <90 g/L, severe anemia as <60 g/L. The t test and χ2 test were used for inter-group comparison. Results: The overall incidence of preoperative anemia was 38.60%(2 885/7 474), and the incidences of mild anemia, moderate anemia and severe anemia were 25.09%(1 875/7 474), 11.37%(850/7 474) and 2.14%(160/7 474), respectively. The overall incidence of postoperative anemia was 61.40%(4 589/7 474). The incidence of mild anemia, moderate anemia and severe anemia were 48.73%(3 642/7 474), 12.20%(912/7 474) and 0.47%(35/7 474), respectively. The proportion of preoperative anemia patients receiving treatment was 26.86% (775/2 885), and the proportion of postoperative anemia patients receiving treatment was 14.93% (685/4 589). The proportions of preoperative anemia patients in grade ⅢA, grade ⅢB, and grade ⅡA hospitals receiving treatment were 26.12% (649/2 485), 32.32% (85/263), and 29.93% (41/137), and the proportions of postoperative anemia patients receiving treatment were 14.61% (592/4 052), 22.05% (73/331), and 9.71% (20/206). The proportion of intraoperative blood transfusion (16.74% (483/2 885) vs. 3.05% (140/4 589), χ²=434.555, P<0.01) and the incidence of postoperative complications (17.78% (513/2 885) vs. 14.08% (646/4 589), χ²=18.553, P<0.01) in the preoperative anemia group were higher than those in the non-anemia group, and the postoperative hospital stay in the preoperative anemia group was longer than that in the non-anemia group ((14.1±7.3) days vs. (13.3±6.2) days, t=5.202, P<0.01). Conclusions: The incidence of perioperative anemia in patients with gastrointestinal neoplasms is high. Preoperative anemia can increase the demand for intraoperative blood transfusion and affect the short-term prognosis of patients. At present, the concept of standardized treatment of perioperative anemia among gastrointestinal surgeons in Hubei Province needs to be improved.

[Effects and mechanism of hepatocyte growth factor-modified human adipose mesenchymal stem cells on wound healing of full-thickness skin defects in diabetic rats].

Objective: To investigate the effects and mechanism of hepatocyte growth factor (HGF)-modified human adipose mesenchymal stem cells (ADSCs) on the wound healing of full-thickness skin defects in diabetic rats. Methods: The experimental research method was adopted. The discarded abdominal adipose tissue was collected from a 35-year-old healthy female who underwent abdominal liposuction in the Department of Plastic Surgery of the First Affiliated Hospital of Air Force Medical University in December 2019. The long spindle-shaped primary ADSCs were obtained by collagenase digestion, and the third passage of cells were identified by flow cytometry to positively express ADSCs surface markers CD29 and CD90 and negatively express CD34 and CD45. The third passage of ADSCs were used for the subsequent experiments. ADSCs were transfected with lentivirus-mediated HGF for 4 h (obtaining HGF modified ADSCs) and then routinely cultured for 24 h. The cell morphology was observed under an inverted phase contrast microscope, and the transfection rate was calculated. Eighty-one male Sprague-Dawley rats aged 4 weeks were induced into diabetic rat model by high glucose and high fat diet combined with streptozotocin injection. A full-thickness skin defect wound of 1.5 cm×1.5 cm was made on the back of each rat. The injured rats were divided into phosphate buffer solution (PBS) group, ADSCs alone group, and HGF-modified ADSCs group according to the random number table, with 27 rats in each group. The rats were injected with the same volume of corresponding substances around the wound on post injury day (PID) 1, 3, and 7, respectively. Nine rats in each group were selected according to the random number table, the wound area of whom was measured on PID 0 (immediately), 3, 7, 10, and 14 (after injection on injection day), and the wound healing rates on PID 3, 7, 10, and 14 were calculated. Nine remaining rats in each group were sacrificed after injection on PID 3 and 7, respectively, and the skin tissue around the wound were collected. The mRNA expressions of inflammatory factors such as tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), and IL-10 on PID 3 and collagen type Ⅰ and Ⅲ on PID 7 were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction. The expression level of vascular endothelial growth factor (VEGF) was detected by enzyme-linked immunosorbent assay on PID 7. The protein expression of nuclear factor κb-p65 on PID 3 and phosphorylation level of protein kinase B (Akt) on PID 7 were detected by Western blotting. Data were statistically analyzed with analysis of variance for repeated measurement, one-way analysis of variance, least significant difference t test, and Bonferroni correction. Results: After 24 h of culture, the HGF-transfected human ADSCs showed good morphology, which was not different with the non-transfected ADSCs, and the transfection rate reached 90%. On PID 3, 7, 10, and 14, the wound healing rates of rats in HGF-modified ADSCs group were (31.5±1.0)%, (75.2±2.0)%, (92.2±1.3)%, and (99.1±1.8)%, respectively, being significantly higher than (21.4±1.3)%, (61.4±1.5)%, (80.1±2.1)%, and (92.4±1.8)% in PBS group and (25.1±2.1)%, (67.2±1.3)%, (89.3±1.4)%, and (95.1±2.1)% in ADSCs alone group (t=1.452, 0.393, 0.436, 0.211, 4.982, 3.011, 4.211, 7.503, P<0.05 or P<0.01). On PID 3, compared with those in PBS group and ADSCs alone group, the mRNA expressions of TNF-α and IL-1ß and protein expression of nuclear factor κb-p65 in the skin tissue around the wound of rats in HGF-modified ADSCs group were significantly decreased (t=7.281, 17.700, 9.447, 6.231, 13.083, 7.783, P<0.01), and the mRNA expression of IL-10 in the skin tissue around the wound of rats in HGF-modified ADSCs group was significantly increased (t=-6.644, -6.381, P<0.01). On PID 7, compared with those in PBS group and ADSCs alone group, the mRNA expressions of collagen type Ⅰ and Ⅲ, the expression level of VEGF, and the phosphorylation level of Akt in the skin tissue around the wound of rats in HGF-modified ADSCs group were significantly increased (t=-5.126, -4.347, -5.058, -3.367, -10.694, -19.876, -4.890, -6.819, P<0.05 or P<0.01). Conclusions: HGF-modified human ADSCs can significantly promote the wound healing of full-thickness skin defects in diabetic rats. The mechanism may be related to the inhibition of TNF-α and IL-1ß expression, the promotion of IL-10, collagen type Ⅰ and Ⅲ, and VEGF expression, which could be related to the inhibition of nuclear factor κB signaling pathway, and the promotion of Akt signaling pathway.

[Pay attention to misdiagnosis and differential diagnosis of gastric gastrointestinal stromal tumor].

Due to the lack of typical symptoms and imaging findings, gastric gastrointestinal stromal tumor (GIST) is easy to be misdiagnosed as other gastric tumors clinically. In clinical practice, clinicians should adopt the multidisciplinary team model, fully understand the characteristics of gastric GIST, grasp the key points of its differential diagnosis from other gastric tumors to achieve precise diagnosis and treatment. This paper analyzes the causes of misdiagnosis and elucidates the differential diagnosis of gastric GIST, aiming to improve the accuracy of preoperative diagnosis, reduce the misdiagnosis, and improve treatment outcomes.

[Clinicopathological characteristics and prognosis of patients with sporadic multiple primary gastrointestinal stromal tumors].

Objective: To investigate the clinicopathological characteristics and prognosis of sporadic multiple primary gastrointestinal stromal tumor (GIST). Methods: A retrospective cohort study was conducted. Case inclusion criteria: (1) postoperative pathological diagnosis of GIST; (2) primary GIST with single lesion or sporadic multiple primary GIST (sporadic GIST was defined as primary GIST other than familial and syndrome-related GIST, and multiple primary GIST was defined as the number of primary GISTs in the same patient ≥ 2); (3) patients with complete clinicopathological data. Those with tumor recurrence or distant metastasis, and with other malignancies were excluded. Medical records of patients with primary GIST who underwent surgical resection in the Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2010 to December 2020 were collected. Patients were divided into sporadic multiple primary GIST group and single primary GIST group according to the number of primary GIST lesions. The clinicopathological data and prognosis of the two groups were observed and compared. Results: A total of 1200 patients with primary GIST were enrolled in this study, including 628 males (52.3%) and 572 females (47.7%), with a median onset age of 58 (19-93) years. Among them, 1165 cases (97.1%) were sporadic primary GIST with single lesion; 35 cases (2.9%) were sporadic multiple primary GIST. Among 35 cases of sporadic multiple primary GIST, 3 cases (8.6%) had acid reflux as the first symptom, which was higher than the single primary GIST group (22/1165, 1.9%) (χ(2)=7.437, P=0.006). There were no significant differences in other clinical characteristics between the two groups (all P>0.05). Patients in the sporadic multiple primary GIST group contained a total of 80 primary tumors. Compared with the single primary GIST group, the sporadic multiple primary GIST group had a higher proportion of tumors originating in the stomach [87.5% (70/80) vs. 59.1% (689/1165)], lower proportion of spindle cell in histology [85.0% (68/80) vs. 93.7% (1092/1165)], higher proportion of positive CD34 [97.5% (78/80) vs. 87.6% (1021/1165)], smaller maximum diameter [maximum diameter ≤2.0 cm: 61.2% (49/80) vs. 28.8% (335/1165)], lower mitotic rate [≤5/50 high-power fields (HPF): 93.8% (75/80) vs. 74.5% (868/1165)], lower risk of recurrence [60.0% (48/80) vs. 23.3% (271/1165)], and the differences were all statistically significant (all P<0.05). The 3-year recurrence-free survival rate in the sporadic multiple primary group and the single primary GIST group was 96.6% and 89.3% respectively (P=0.160), and the 3-year overall survival rate was 100.0% and 92.8%, respectively (P=0.088). Conclusions: The most common type of sporadic multiple primary GIST is multiple tumors originating in the stomach at the same time. Compared with primary GIST with single lesion, sporadic multiple primary GIST presents smaller maximum diameter and lower mitotic rate. The prognosis of patients between two groups is not significantly different.

[Adherence to adjuvant with therapy imatinib in patients with gastrointestinal stromal tumor: a national multi-center cross-sectional study].

Objective: To analyze the current adherence to imatinib in patients with gastrointestinal stromal tumors (GIST) in China and its influencing factors. Methods: A cross-sectional survey was conducted. Study period: from October 1, 2020 to November 31, 2020. Study subjects: GIST patients taking imatinib who were diagnosed and treated in public tertiary level A general hospitals or oncology hospitals; those who had not been pathologically diagnosed, those who never received imatinib, or those who had taken imatinib in the past but stopped afterwards were excluded. The Questionnaire Star online surgery platform was used to design a questionnaire about the adherence to adjuvant imatinib therapy of Chinese GIST patients. The link of questionnaire was sent through WeChat. The questionnaire contained basic information of patients, medication status and Morisky Medication Adherence Scale. Results: A total of 2162 questionnaires from 31 provinces, autonomous regions, and municipalities were collected, of which 2005 were valid questionnaires, with an effective rate of 92.7%. The survey subjects included 1104 males and 901 females, with a median age of 56 (22-91) years old. Working status: 609 cases (30.4%) in the work unit, 729 cases (36.4%) of retirement, 667 cases of flexible employment or unemployment (33.3%). Education level: 477 cases (23.8%) with bachelor degree or above, 658 cases (32.8%) of high school, 782 cases (39.0%) of elementary or junior high school, 88 cases (4.4%) without education. Marital status: 1789 cases (89.2%) were married, 179 cases (8.9%) divorced or widowed, 37 cases (1.8%) unmarried. Two hundred and ninety-four patients (14.7%) had metastasis when they were first diagnosed, including 203 liver metastases, 52 peritoneal metastases, and 39 other metastases. One thousand eight hundred and sixty-nine patients underwent surgical treatment, of whom 1642 (81.9%) achieved complete resection. The median time of taking imatinib was 25 (1-200) months. Common adverse reactions of imatinib included 1701 cases (84.8%) of periorbital edema, 1031 cases (51.4%) of leukopenia, 948 cases (47.3%) of fatigue, 781 cases (39.0%) of nausea and vomiting, 709 cases (35.4%) of rash, and 670 cases (33.4%) of lower extremity edema. The score of the Morisky Medication Adherence Scale showed that 392 cases (19.6%) had poor adherence, 1023 cases (51.0%) had moderate adherence, and 590 cases (29.4%) had good adherence. Univariate analysis showed that gender, age, work status, economic income, residence, education level, marriage, the duration of taking medication and adverse reactions were associated with adherence to adjuvant imatinib therapy (all P<0.05). Multivariate analysis showed that female (OR=1.264, P=0.009), non-retirement (OR=1.454, P=0.001), monthly income ≤4000 yuan (OR=1.280, P=0.036), township residents (OR=1.332, P=0.005), unmarried or divorced or widowed (OR=1.362, P=0.026), the duration of imatinib medication >36 months (OR=1.478, P<0.001) and adverse reactions (OR=1.719, P=0.048) were independent risk factors for poor adherence to adjuvant imatinib. Among patients undergoing complete resection, 324 (19.7%) had poor adherence, 836 (50.9%) had moderate adherence, and 482 (29.4%) had good adherence. Meanwhile, 55 patients with good adherence (11.4%) developed recurrence after surgery, 121 patients with moderate adherence (14.5%) developed recurrence, 61 patients with poor adherence (18.8%) developed recurrence, and the difference was statistically significant (P=0.017). Conclusions: The adherence to adjuvant therapy with imatinib in Chinese GIST patients is relatively poor. Females, non-retirement, monthly income ≤4000 yuan, township residents, unmarried or divorced or widowed, the duration of imatinib medication >36 months, and adverse reactions are independently associated with poor adherence of GIST patients. Those with poor adherence have a higher risk of recurrence after surgery. Positive interventions based on the above risk factors are advocated to improve the prognosis of patients with GIST.

[Expression of microRNA-296 in rabbit hypertrophic scars and its role to human fibroblasts].

Objective: To investigate the expression of microRNA-296 (miR-296) in rabbit hypertrophic scars and its role in human fibroblasts (HFbs). Methods: The experimental method was used. Twelve healthy adult New Zealand long-eared rabbits regardless gender were randomly divided into normal control group and scar group, with 6 rabbits in each group. The rabbit ear hypertrophic scar model was created in scar group according to the literature, and the rabbits in normal control group did not receive any treatment. On 60 days after setting up the models in scar group, hematoxylin-eosin staining was performed to observe the growth and arrangement of fibroblasts (Fbs) in the ear scars and skin tissue of rabbits in the two groups. The mRNA expressions of miR-296 and transforming growth factor-ß1 (TGF-ß1) in ear scars and skin tissue of rabbits in the two groups were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction, and the correlation of mRNA between miR-296 and TGF-ß1 was performed with Pearson regression analysis. Two batches of HFbs were used and transfected respectively with corresponding sequences, with the 1st batch being divided into TGF-ß1 wild type+miR-296 negative control group and TGF-ß1 wild type+miR-296 mimic group and the 2nd batch being divided into TGF-ß1 mutant type+miR-296 negative control group and TGF-ß1 mutant type+miR-296 mimic group. At 48 h after transfection, luciferase reporter gene detection kit was used to detect the luciferase and renal luciferase expression of TGF-ß1 in the cells of each group, with their ratio being used to reflect the gene expression level. Two batches of HFbs were used, and each batch of cells were divided into miR-296 negative control group and miR-296 mimic group, being transfected with the corresponding sequences. At 0 (immediately), 12, 24, 36, and 48 h after transfecting the first batch of cells, the cell proliferation was detected by thiazolyl blue method. At 24 h after transfecting the second batch of cells, the expression of TGF-ß1 and collagen type Ⅰ was detected by Western blotting. The number of samples in cell experiments was 3. Data were statistically analyzed with analysis of variance for factorial design, independent sample t test. Results: On 60 days after setting up the models in scar group, the Fbs of rabbit ear scar tissue in scar group proliferated and arranged disorderly, while the growth and arrangement of Fbs in rabbit ear skin tissue in normal control group were normal. The mRNA expression of miR-296 of rabbit scar tissue in scar group (0.65±0.11) was significantly lower than 1.19±0.12 of rabbit ear skin tissue in normal control group (t=5.175, P<0.01). The mRNA expression of TGF-ß1 of rabbit ear scar tissue in scar group (1.47±0.06) was significantly higher than 1.10±0.03 of rabbit ear skin tissue in normal control group (t=12.410, P<0.01). Pearson regression analysis showed that there was a negative correlation between the mRNA expression of miR-296 and TGF-ß1 in the ear scars and skin tissue of 12 rabbits (F=7.278, P<0.05). At 48 h after transfection, the gene expression of TGF-ß1 of cells in TGF-ß1 wild type+miR-296 mimic group was significantly lower than that in TGF-ß1 wild type+miR-296 negative control group (t=35.190, P<0.01), while the gene expression of TGF-ß1 of cells in the two TGF-ß1 mutant type groups were close (P>0.05). The HFbs proliferation ability in miR-296 mimic group was significantly lower than that in miR-296 negative control group at 12, 24, 36, and 48 h after transfection(t=3.275, 11.980, 10.460, 17.260, P<0.05 or P<0.01). At 24 h after transfection, the protein expressions of TGF-ß1 and type Ⅰ collagen of cells in miR-296 negative control group were significantly higher than those in miR-296 mimic group (t=3.758, 29.390, P<0.05 or P<0.01). Conclusions: The miR-296 expression in rabbit hypertrophic scars is down-regulated; miR-296 can inhibit the proliferation of HFbs and the expression of type Ⅰ collagen by down regulating the expression of TGF-ß1.

[Clinical effects of expanded flap in repairing the wounds with exposed titanium mesh after cranioplasty with titanium mesh].

Objective: To explore the clinical effects of expanded flap made by skin and soft tissue expander (hereinafter referred to as expander) in repairing the wounds with exposed titanium mesh after cranioplasty with titanium mesh. Methods: A retrospective observational study was conducted. From April 2015 to October 2019, 13 patients with wounds with exposed titanium mesh after cranioplasty with titanium mesh were admitted to the First Affiliated Hospital of Air Force Medical University, including 10 males and 3 females, aged 18 to 70 years. Exposure of titanium mesh occurred 3 months to 4 years after cranioplasty with titanium mesh. The wound area of exposed titanium mesh ranged from 1.5 cm×0.6 cm to 6.3 cm×6.0 cm. In the first stage, one or two square expanders with rated capacity of 50-200 mL were placed under the normal scalp 1 cm away from the edge of the wound surface of exposed titanium mesh. The water injection time was 2 to 3 months with the total water injection volume being 1.6 to 2.0 times of the rated capacity of expander. In the second stage, the expander was removed and the expanded flap (size ranging from 4.1 cm×1.8 cm to 9.1 cm×7.9 cm) was transferred to repair the wound of exposed titanium mesh. The placement site of the expander, the transfer form of the expanded flap, the postoperative wound healing of the titanium mesh exposed site, and the survival of expanded flap were recorded. The scar of the head incision and the appearance of head were followed up. Results: Among the patients in this group, the expanders of 7 were placed in the temporal region, while the other 6 were placed at the top. The 11 patients were treated with advanced expanded flap, while the other 2 patients were treated with pedicled expanded flap. The head wounds of patients in this group successfully healed with retaining of the titanium mesh. The wound was healed after dressing change in 1 patient with necrosis at the tip of the expanded flap. The expanded flaps of 12 patients survived after transfer. Patients in this group were followed up for 12 months after surgery, the exposed titanium meshes were retained, the incisions healed well with the scars concealed, the hair on the scalp grew well, and the appearance of head was comparatively good. Conclusions: Using expanded flap in the repair of the wounds with exposed titanium mesh after cranioplasty with titanium mesh can effectively cover the wound and retain the titanium mesh, achieving good function and appearance.

[Research advances on the regulation of interleukin-17 signal transduction and the implication of interleukin-17 in sepsis].

Sepsis remains a leading cause of death in critical patients. Both excessive inflammatory response and long-term immunosuppression can lead to the death of sepsis patients. As a key pro-inflammatory cytokine, interleukin-17 (IL-17) plays an important role in the body's inflammatory response and immune system. The signal transduction of IL-17 is a key link in maintaining the body's health and participating in the onset and development of sepsis. This review mainly summarizes and discusses the regulation of IL-17 signal transduction and pathogenic and protective role of IL-17 in sepsis.