ObjectiveTo explore the role of cucurbitacin B （CuB） in inducing ferroptosis in 4T1 cells and its mechanism. MethodsThe effects of CuB（0.2， 0.4， 0.8 μmol·L^-1）on the proliferation ability of 4T1 cells in vitro were detected using the methyl thiazolyl tetrazolium （MTT） assay. The clonogenic ability of 4T1 cells was detected by the plate cloning assay， and the levels of lactate dehydrogenase （LDH） in 4T1 cells were detected by the use of a kit. The mitochondrial membrane potential and reactive oxygen species （ROS） levels in 4T1 cells were detected by flow cytometry， and the mitochondrial ultrastructure of 4T1 cells was observed by transmission electron microscopy. The western blot was used to detect the expression of ferroptosis-related protein p53 in 4T1 cells， solute carrier family 7 member 11 （SCL7A11）， glutathione peroxidase 4 （GPX4）， long-chain acyl-CoA synthetase 4 （ACSL4）， transferrin receptor protein 1 （TFR1）， and ferritin heavy chain 1 （FTH1）. ResultsCompared with that in the blank group， the survival rate of 4T1 cells in CuB groups was significantly decreased （P<0.05）， and the number of cell clones in CuB groups was significantly reduced （P<0.01）. In addition， compared with that in the blank group， the leakage of LDH in cells in CuB groups was significantly increased （P<0.01）， and the mitochondrial membrane potential of cells in CuB groups decreased significantly （P<0.01）. Cellular ROS levels were significantly elevated in CuB groups （P<0.01）. The mitochondria of cells in CuB groups were obviously wrinkled， and the mitochondrial cristae were reduced or even disappeared. Compared with that in the blank group， the protein expression of p53， ACSL4， and TFR1 were significantly up-regulated in CuB groups （P<0.05）， and that of SLC7A11， GPX4， and FTH1 were significantly down-regulated （P<0.05）. ConclusionCuB may inhibit SLC7A11 and GPX4 expression by up-regulating the expression of p53， which in turn regulates the p53/SLC7A11/GPX4 signaling pathway axis and accelerates the generation of lipid peroxidation substrate by up-regulating the expression of ACSL4. It up-regulates TFR1 expression to promote cellular uptake of Fe³⁺ and down-regulates the expression of FTH1 to reduce the ability of iron storage， resulting in an elevated free Fe²⁺ level. It catalyzes the Fenton reaction， generates excess ROS， imbalances the antioxidant system and iron metabolism， and then induces ferroptosis in 4T1 cells.

ObjectiveTo explore the role of cucurbitacin B （CuB） in inducing ferroptosis in 4T1 cells and its mechanism. MethodsThe effects of CuB（0.2， 0.4， 0.8 μmol·L^-1）on the proliferation ability of 4T1 cells in vitro were detected using the methyl thiazolyl tetrazolium （MTT） assay. The clonogenic ability of 4T1 cells was detected by the plate cloning assay， and the levels of lactate dehydrogenase （LDH） in 4T1 cells were detected by the use of a kit. The mitochondrial membrane potential and reactive oxygen species （ROS） levels in 4T1 cells were detected by flow cytometry， and the mitochondrial ultrastructure of 4T1 cells was observed by transmission electron microscopy. The western blot was used to detect the expression of ferroptosis-related protein p53 in 4T1 cells， solute carrier family 7 member 11 （SCL7A11）， glutathione peroxidase 4 （GPX4）， long-chain acyl-CoA synthetase 4 （ACSL4）， transferrin receptor protein 1 （TFR1）， and ferritin heavy chain 1 （FTH1）. ResultsCompared with that in the blank group， the survival rate of 4T1 cells in CuB groups was significantly decreased （P<0.05）， and the number of cell clones in CuB groups was significantly reduced （P<0.01）. In addition， compared with that in the blank group， the leakage of LDH in cells in CuB groups was significantly increased （P<0.01）， and the mitochondrial membrane potential of cells in CuB groups decreased significantly （P<0.01）. Cellular ROS levels were significantly elevated in CuB groups （P<0.01）. The mitochondria of cells in CuB groups were obviously wrinkled， and the mitochondrial cristae were reduced or even disappeared. Compared with that in the blank group， the protein expression of p53， ACSL4， and TFR1 were significantly up-regulated in CuB groups （P<0.05）， and that of SLC7A11， GPX4， and FTH1 were significantly down-regulated （P<0.05）. ConclusionCuB may inhibit SLC7A11 and GPX4 expression by up-regulating the expression of p53， which in turn regulates the p53/SLC7A11/GPX4 signaling pathway axis and accelerates the generation of lipid peroxidation substrate by up-regulating the expression of ACSL4. It up-regulates TFR1 expression to promote cellular uptake of Fe³⁺ and down-regulates the expression of FTH1 to reduce the ability of iron storage， resulting in an elevated free Fe²⁺ level. It catalyzes the Fenton reaction， generates excess ROS， imbalances the antioxidant system and iron metabolism， and then induces ferroptosis in 4T1 cells.

ObjectiveTo investigate the induction of ferroptosis by polyphyllin Ⅱ （PPⅡ） in hepatocellular carcinoma HepG2 cells and its underlying mechanism. MethodThe effect of PPⅡ （0， 1.5， 3.0， 4.5， 6.0， 9.0， 18.0 mg·L^-1） on the in vitro proliferation of HepG2 cells was assessed using the methyl thiazolyl tetrazolium （MTT） assay. Colony formation ability of HepG2 cells was evaluated through a colony formation assay. Cell migration ability was assessed via a scratch assay. Lactate dehydrogenase （LDH） content in HepG2 cells was measured using a kit. Reactive oxygen species （ROS） levels in HepG2 cells were observed using a fluorescence inverted microscope. Malondialdehyde （MDA）， glutathione （GSH）， and free Fe²⁺ content in HepG2 cells were detected using respective kits. The mitochondrial ultrastructure in HepG2 cells was observed by transmission electron microscopy. The expression of ferroptosis-related proteins p53， solute carrier family 7 member 11 （SLC7A11）， glutathione peroxidase 4 （GPX4）， long-chain acyl-CoA synthetase 4 （ACSL4）， and transferrin receptor 1 （TFR1） in HepG2 cells was detected using Western blot. ResultCompared with the control group， the PPⅡ treatment groups showed significantly decreased survival rate of HepG2 cells in a dose-dependent manner （P<0.01）， significantly reduced number of cell colonies （P<0.01）， significantly shortened scratch healing distance， inverse correlation of the migration distance with drug concentration （P<0.01）， significantly increased LDH leakage in cells （P<0.01）， significantly enhanced relative fluorescence intensity of intracellular ROS， and significantly increased accumulation of lipid peroxide MDA （P<0.01）， decreased intracellular GSH content with increasing drug concentration （P<0.01）， and significantly enhanced fluorescence intensity of FeRhoNox-1 in cells （P<0.01）. Moreover， cells exhibited vacuolation， and mitochondria showed significant shrinkage with reduced or even disappeared cristae. Compared with the results in the control group， the expression of p53， ACSL4， and TFR1 proteins significantly increased， while the expression of SLC7A11 and GPX4 proteins significantly decreased in the PPⅡ treatment groups （P<0.05）. ConclusionIn summary， PPⅡ induces ferroptosis in HepG2 cells by regulating the p53/SLC7A11/GPX4 signaling axis， promoting ACSL4 expression and Fe³⁺ uptake， leading to an imbalance in the antioxidant system.

In the wake of the COVID-19 pandemic, only through whole-hearted cooperation and joined efforts can medical institutions, governments, and social organizations cope with emergency, convert the crisis into opportunities, promote modern governance and accomplish high-quality development in the fight against the pandemic. Taking the First Affiliated Hospital of Xi’an Jiaotong University as an example, this paper analyzes the all-media communication matrix of "one network platform, 3W + N" that the hospital established during the pandemic by combining the authoritative official website with WeChat, Wesee, Weibo and that other publicity media. The study explores how to create a publicity brand that is mindful, poignant, compassionate and devoted and maintains its scientific and refined management, so as to achieve the professional goal of educating the public, shouldering the responsibility in the combat against the pandemic, and taking the lead in the research on the pandemic.

Objective:To explore the effect of three-dimensional(3D) design and printing in the reoperation of asymmetric deformity after orthognathic surgery.Methods:Patients of facial asymmetry after orthognathic surgery were included in the Department of Stomatology, Shenzhen University General Hospital and Department of Oral & Maxillofacial Surgery, Shenzhen Stomatology Hospital Affiliated to Shenzhen University from January 2016 to August 2020. Surgical plans and guide plates (positioning guide plate, bone cutting guide plate, reset guide plate) were made by 3D design and printing. During the operations, guide plates were used to guide osteotomy. The facial shape satisfaction of clinicians/patients/third-party were recorded and analyzed at preoperation and 6-12 months postoperation. These patients’ CT scan data was imported to the digital surgery software. Then the distance of chin-midpoint to mid-sagittal plane and the difference of bilateral protuberant point of mandible body to mid-sagittal plane were measured at preoperation and 6-12 months postoperation to determine whether the asymmetry were corrected and postoperative distance were the same as the preoperative design. Data analysis was conducted using SPSS 17.0 statistical software, and measurement data were expressed as Mean±SD. The preoperative and postoperative satisfaction of patients/clinicians/third-party, digital data of preoperation/postoperation and digital data of design-operations/postoperation were analyzed by paired t-test. Analysis of variance and dunnett- t test were used to compare the satisfaction of the surgeon, the third party and patients before and after operation. Results:There were 16 cases of facial asymmetry after orthognathic surgery, including 3 males and 13 females, aged from 18 to 35 years. In 9 cases, genioplasty were used to correct chin deviation. In the other 4 cases, unilateral buccal cortical bone resection were used to correct mandibular body deviation. In the last 3 cases, genioplasty and unilateral buccal cortical bone resection were both applied. All 16 patients successfully received the operation according to the preoperative digital designed plate. Postoperative follow-up ranged 6 months to 1 year. In the 12 cases of genioplasty, the distance of chin-midpoint to mid-sagittal plane reduced from(4.99±0.83) mm preoperatively to (1.63±0.80) mm postoperatively and the difference significant ( t=9.09, P<0.001). There was no significant difference between the distance of preoperative design [(1.50±0.43) mm] and the postoperative one ( t=-0.83, P=0.423). In the 7 cases of unilateral buccal cortical bone resection, the difference of bilateral protuberant point of mandible body to mid-sagitta plane reduced from (7.26±1.20) mm preoperatively to (2.44±0.56) mm postoperatively and the difference was statistically significant ( t=10.26, P<0.001). There was no significant difference was observed between the distance of preoperative design [(2.39±0.16) mm] and the postoperative one ( t=-0.29, P=0.779). The preoperative satisfaction of patients, clinicians and third-party were 65.94±8.21, 79.69±5.91, 79.38±7.50. The postoperative satisfaction of patients, clinicians and third-party were 90.00±5.48, 90.63±2.50, 90.00±4.08. The postoperative satisfaction of patients, chief surgeon and third party was higher than that preoperative satisfaction and the difference was statistically significant( t=-9.15, P<0.001; t=-7.50, P<0.001; t=-6.04, P<0.001). The difference of preoperation satisfaction was statistically significant( F=18.66, P<0.001). The difference of satisfaction of the clinicians and the patients was statistically significant ( P<0.001). The difference of satisfaction of the third-party and the patients was statistically significant ( P<0.001). The difference of postoperation satisfaction was not statistically significant( F=0.12, P=0.889). Conclusions:3D design and printing can 3D analyze comprehensively, simulate surgery accurately, visualize proposed result and guide 3D printing digital guiding plate to perform surgery accurately. In addition, it can improve postoperative satisfaction. So 3D design and printing had obvious advantages in the secondary surgery of asymmetric deformity correction after orthognathic surgery.

Objective:To explore the effect of three-dimensional(3D) design and printing in the reoperation of asymmetric deformity after orthognathic surgery.Methods:Patients of facial asymmetry after orthognathic surgery were included in the Department of Stomatology, Shenzhen University General Hospital and Department of Oral & Maxillofacial Surgery, Shenzhen Stomatology Hospital Affiliated to Shenzhen University from January 2016 to August 2020. Surgical plans and guide plates (positioning guide plate, bone cutting guide plate, reset guide plate) were made by 3D design and printing. During the operations, guide plates were used to guide osteotomy. The facial shape satisfaction of clinicians/patients/third-party were recorded and analyzed at preoperation and 6-12 months postoperation. These patients’ CT scan data was imported to the digital surgery software. Then the distance of chin-midpoint to mid-sagittal plane and the difference of bilateral protuberant point of mandible body to mid-sagittal plane were measured at preoperation and 6-12 months postoperation to determine whether the asymmetry were corrected and postoperative distance were the same as the preoperative design. Data analysis was conducted using SPSS 17.0 statistical software, and measurement data were expressed as Mean±SD. The preoperative and postoperative satisfaction of patients/clinicians/third-party, digital data of preoperation/postoperation and digital data of design-operations/postoperation were analyzed by paired t-test. Analysis of variance and dunnett- t test were used to compare the satisfaction of the surgeon, the third party and patients before and after operation. Results:There were 16 cases of facial asymmetry after orthognathic surgery, including 3 males and 13 females, aged from 18 to 35 years. In 9 cases, genioplasty were used to correct chin deviation. In the other 4 cases, unilateral buccal cortical bone resection were used to correct mandibular body deviation. In the last 3 cases, genioplasty and unilateral buccal cortical bone resection were both applied. All 16 patients successfully received the operation according to the preoperative digital designed plate. Postoperative follow-up ranged 6 months to 1 year. In the 12 cases of genioplasty, the distance of chin-midpoint to mid-sagittal plane reduced from(4.99±0.83) mm preoperatively to (1.63±0.80) mm postoperatively and the difference significant ( t=9.09, P<0.001). There was no significant difference between the distance of preoperative design [(1.50±0.43) mm] and the postoperative one ( t=-0.83, P=0.423). In the 7 cases of unilateral buccal cortical bone resection, the difference of bilateral protuberant point of mandible body to mid-sagitta plane reduced from (7.26±1.20) mm preoperatively to (2.44±0.56) mm postoperatively and the difference was statistically significant ( t=10.26, P<0.001). There was no significant difference was observed between the distance of preoperative design [(2.39±0.16) mm] and the postoperative one ( t=-0.29, P=0.779). The preoperative satisfaction of patients, clinicians and third-party were 65.94±8.21, 79.69±5.91, 79.38±7.50. The postoperative satisfaction of patients, clinicians and third-party were 90.00±5.48, 90.63±2.50, 90.00±4.08. The postoperative satisfaction of patients, chief surgeon and third party was higher than that preoperative satisfaction and the difference was statistically significant( t=-9.15, P<0.001; t=-7.50, P<0.001; t=-6.04, P<0.001). The difference of preoperation satisfaction was statistically significant( F=18.66, P<0.001). The difference of satisfaction of the clinicians and the patients was statistically significant ( P<0.001). The difference of satisfaction of the third-party and the patients was statistically significant ( P<0.001). The difference of postoperation satisfaction was not statistically significant( F=0.12, P=0.889). Conclusions:3D design and printing can 3D analyze comprehensively, simulate surgery accurately, visualize proposed result and guide 3D printing digital guiding plate to perform surgery accurately. In addition, it can improve postoperative satisfaction. So 3D design and printing had obvious advantages in the secondary surgery of asymmetric deformity correction after orthognathic surgery.

Objective: To introduce the method for reconstruction of thumb defect by transplanting free flap of second toe combined with the hallucis flap. Methods: From June, 2012 to February, 2017, a total of 9 cases of thumb defect were treated. The average age of these 9 patients was 26 years. The plane of thumb defect was class II area A to class III area A. According to the condition of thumb defect, designed the incision on the hallux and the second toe of the contralateral foot, and cut the 2nd digit and big-toe nail flap with a common arterial trunk. The nail of hallucis flap was rotated 90 degree and connected to the distal end of the 2nd toe. The hallucis flap covered the narrow neck of the 2nd toe. Thus, the circumference of the reconstructed finger and the length of the toenail were increased. Regular followed-up was made after operation. Results: All 9 transplantation flaps survived, and donor sites healed primarily. Postoperative followed-up period ranged from 4 to 12 (averge,7) months. All the reconstructed thumbs survived and donor toes were in satisfactory appearances. According to the Functional Assessment Criteria of the Upper Limb Formulated by the Hand Surgery Society of Chinese Medical Association, the outcomes were graded as excellent in 6 cases and good in 3 cases. All the patients were able to manage their daily activities independently. Donor toe injury was small, and their shape and function was good. Conclusion Free flap of second toe combined with hallucis can effectively improve the appearance of the reconstructed thumb. The appearance of the reconstructed thumb is symmetrical, beautiful, and the function is good.

CAR-T cell therapy that targets surface antigens to kill tumor cells specifically has recently become another cornerstone in tumor immunotherapy. In this study, a lentiviral expression plasmid of CAR targeting human epidermal growth factor receptor 2 (HER2) was constructed by genetic engineering. The recombinant plasmid was co-transfected with other packaging plasmids into HEK293T cells by calcium phosphate precipitation to generate lenti-car, which are CAR lentiviral particles. HER2-specific CAR-T cells were obtained by transducing human peripheral blood mononuclear cells with lenti-car. Their specific inhibitory effects on HER2-positive and HER2-negative tumor cells were analyzed in vitro. The constructed CAR-T cells were specifically activated by HER2-expressing tumor cells as indicated by secretion of IFN-γ and IL-2. The inhibitory rate on HER2-positive SK-OV-3 cell line was (58.47±1.72)%, significantly higher than that on the mock-treated control group (P<0.05). The inhibitory rate on HER2-negative K562 cell lines was (11.74±2.37)%, which was not significantly different from that on the control group (P>0.05). Furthermore, when we transfected a HER2-expressing vector into K562, the inhibitory rate increased to (30.41±7.59)%, which was higher than that on HER2-negative K562 (P<0.05). Thus, the constructed second-generation HER2-specific CAR-T cells specifically suppressed growth of tumor cells overexpressing HER2 protein, suggesting that HER2-specific CAR-T cells might prove useful for immunotherapy of HER2-positive cancer.

Objective To investigate the clinical efficacy of free flap transplantation in repairing the Gustilo type ⅢB and ⅢC fractures of tibia and fibula combined with soft tissue defects.Methods A retrospective case series study was conducted on the clinical data of 46 patients who had Gustilo type ⅢB and ⅢC fractures of tibia and fibula with soft tissue defects admitted from June 2013 to January 2017.There were 34 males and 12 females,aged 1-67 years (mean,39 years).The wound defect areas ranged from 6 cm × 20 cm to 7 cm × 38 cm.According to the Gustilo fracture classification,there were 31 cases of type ⅢB and 15 cases of type ⅢC.According to the AO fracture typing,there were five cases of type A,23 type B,and 18 type C.All patients were repaired with free flap transplantation,among which 40 patients were treated with anterolateral thigh flap and six with latissimus dorsi flap.The areas of anterolateral thigh flap ranged from 6 cm × 13 cm to 14 cm ×32 cm,and those of the latissimus dorsi flap from 6 cm × 22 cm to 7 cm × 40 cm.Efficacy was evaluated by flap survival rate,complications,fracture healing time,lower limb function scoring system (LEFS),and skin flap function.Results All limbs were salvaged successfully.One case of total flap necrosis and eight cases of postoperative crisis occurred.After active exploration and treatment,three cases were seen distal local necrosis,and the total survival rate was 91％.Infection at the donor site was found in two cases.The complication incidence rate was 4％.All patients were followed up for 7-42 months,with an average of 19 months.The fracture healing time averaged 43.5 weeks,and the LEFS score averaged 54 points.According to the seven indexes of flap function,the results were excellent in 1 1 cases,good in 29 cases,fair in four cases,and poor in two cases,with an excellent and good rate of 87％.Conclusion Free flap transplantation can achieve satisfactory efficacy in treating Gustilo type ⅢB and ⅢC of tibia and fibula combined with soft tissue defects,with high limb salvage rate and good function recovery.

Objective To investigate the clinical therapy of early internal fixation combined with perforator flap for forearm open fractures of Gustilo types Ⅲ B & Ⅲ C.Methods A retrospective study was conducted of the 45 patients with forearm open fracture of Gustilo type ⅢB or Ⅲ C who had been treated from July 2012 to October 2016 at Department of Traumatic Orthopaedics,The Ninth People's Hospital of Wuxi.They were 26 men and 19 women,aged from 20 to 61 years (average,41 years).Twenty cases were Gustilo type ⅢB and 25 Gustilo type ⅢC.By AO classification,8 cases were type A,21 ones type B,and 16 ones type C.The wound size ranged from 4 cm × 3 cm to 36 cm × 8 cm.Thirty-three patients were treated by primary internal fixation plus secondary transfer with a perforator flap,12 ones by secondary internal fixation plus transfer with a perforator flap.The period from injury to secondary flap transfer ranged from 5 to 20 days (average,12 days).In this series,36 anterolateral thigh perforator flaps,5 latissimus dorsal muscular flaps and 4 lateral arm flaps were transferred.Results All the 45 free flaps survived with no deep infection or osteomyelitis.Partial necrosis happened at the distal ends of 2 latissimus dorsal muscular flaps which were cured by skin graft.Postoperative circulatory crisis happened after transfer of an anterolateral thigh perforator flap which survived with 5 cm skin necrosis at the distal end after successful surgical exploration.Superficial wound infection happened in 12 patients with no deep or bone infection.All the patients were followed up for 12 to 36 months (average,18.5 months).All the flaps were soft in texture,with varying degrees of pigmentation.The sensory recovery was S2 in 8 flaps,S3 in 29 flaps,and S4 in 8 flaps.Obvious scar hyperplasis was observed at the donor site in 5 cases while no obvious scar hyperplasis was observed in the other 40 ones.All the fractures got united after 4 to 14 months (average,8.6 months).Nonunion happened in 2 patients who were treated with autologous iliac graft 8 months after operation.By Anderson criteria,the curative efficacy was assessed as excellent in 15 cases,as good in 21,as fair in 7 and as poor in 2,yielding an excellent to good rate of 80.0％.Conclusion Early internal fixation combined with perforator flap transfe is an effective strategy for treatment of forearm open fractures with soft tissue defects of Gustilo types Ⅲ B &Ⅲ C,due to its advantages of shortened treatment period,possibility for early rehabilitation,decreased complications and satisfactory functional recovery.