Objective To investigate the damage mechanism of extracellular vesicles(EVs)derived from ves-tibular schwannoma(VS)on HEI-OC1 cells and the protective effect of the ferroptosis inhibitor ferrostatin-1(Fer-1).Methods Tumor tissues and clinical data were collected from four patients with stage Ⅱ or Ⅲ VS,classified as grade D according to the AAO-HNS hearing classification.Primary VS cells were extracted,and their conditioned supernatant was collected.EVs were isolated using ultracentrifugation and identified.HEI-OC1 cells were cultured in vitro and divided into three groups:the control group(no treatment),the EVs group(treated with 3000 parti-cles/cell VS-EVs for 24 hours),and the EVs+Fer-1 group(pretreated with 20 μmol/L Fer-1 for 2 hours followed by co-culture with 3000 particles/cell VS-EVs for 24 hours).Cell viability was assessed using the CCK-8 assay,re-active oxygen species(ROS)levels were quantified using the DCFH-DA fluorescent probe,and lipid peroxidation was evaluated using the BODIPY 581/591 C11 probe.Results Compared with the control group,the EVs group showed significantly reduced cell viability(P＜0.001)and increased levels of ROS(P＜0.001)and lipid peroxides(P＜0.001).However,the EVs+Fer-1 group exhibited significantly restored cell viability(P＜0.001)and re-duced levels of ROS and lipid peroxidation(P＜0.001).Conclusion VS-derived EVs disrupts redox homeostasis,promotes intracellular accumulation of lipid peroxides and ROS,and induces ferroptosis in HEI-OC1 cells.Fer-1 significantly alleviates VS-EVs-induced ferroptosis,thereby protecting HEI-OC1 cells from damage.

Objective To investigate the damage mechanism of extracellular vesicles(EVs)derived from ves-tibular schwannoma(VS)on HEI-OC1 cells and the protective effect of the ferroptosis inhibitor ferrostatin-1(Fer-1).Methods Tumor tissues and clinical data were collected from four patients with stage Ⅱ or Ⅲ VS,classified as grade D according to the AAO-HNS hearing classification.Primary VS cells were extracted,and their conditioned supernatant was collected.EVs were isolated using ultracentrifugation and identified.HEI-OC1 cells were cultured in vitro and divided into three groups:the control group(no treatment),the EVs group(treated with 3000 parti-cles/cell VS-EVs for 24 hours),and the EVs+Fer-1 group(pretreated with 20 μmol/L Fer-1 for 2 hours followed by co-culture with 3000 particles/cell VS-EVs for 24 hours).Cell viability was assessed using the CCK-8 assay,re-active oxygen species(ROS)levels were quantified using the DCFH-DA fluorescent probe,and lipid peroxidation was evaluated using the BODIPY 581/591 C11 probe.Results Compared with the control group,the EVs group showed significantly reduced cell viability(P＜0.001)and increased levels of ROS(P＜0.001)and lipid peroxides(P＜0.001).However,the EVs+Fer-1 group exhibited significantly restored cell viability(P＜0.001)and re-duced levels of ROS and lipid peroxidation(P＜0.001).Conclusion VS-derived EVs disrupts redox homeostasis,promotes intracellular accumulation of lipid peroxides and ROS,and induces ferroptosis in HEI-OC1 cells.Fer-1 significantly alleviates VS-EVs-induced ferroptosis,thereby protecting HEI-OC1 cells from damage.

Objective:To design an improved lamina hook system and compare its biomechanical properties with traditional lamina hook system in fixation of lumbar spondylolysis.Methods:The thin layer CT data of the lumbosacral vertebrae of 20 healthy young male servicemen who underwent physical examination in the outpatient department of the 940th Hospital of Joint Logistics Support Force of PLA from January 2021 to August 2022 were collected. The age of the subjects was 20-30 years [(25.0±3.0)years]. A 3-dimensional model of the L 5 vertebral body was constructed using the 3-dimensional modeling software. The new improved lamina hook was designed according to the measurements including the thickness of the middle area, the longest longitudinal diameter, the curvature radius of the lower edge, the angle between the upper and lower tail ends, the thickness of the lower edge, and the longest diameter of the lower edge of the bilateral L 5 vertebral plates. One serviceman was selected from the aforementioned group to construct a linear finite element model of segments L 4-S using the 3-dimensional virtual software (normal model, model A), based on which, the L 5 bilateral spondylolysis model (model B), improved lamina hook model (model C) and traditional lamina hook models (model D) were designed. By constraining both sides of the sacrum and applying a longitudinal load of 400 N on the L 4 vertebral body, the upper 1/3 gravity of the body was simulated, and with a bending moment of 10 N·m along the X, Y, and Z directions, motions of forward flexion, backward extension, lateral bending, rotation, etc were simulated. The range of motion of segment L 4/5 and L 5/S 1 of model A was evaluated and compared with the findings of the previous researches to verify its effectiveness. The overall range of motion of models A, B, C, and D, the range of motion of segment L 4/5 and L 5/S 1, the maximum overall displacement, the maximum displacement and stress of the isthmus, the stress distribution and maximum stress of internal fixation of models C and D, and the stress distribution and maximum stress of the vertebral body of models C and D were compared. Results:(1) During forward flexion, backward extension, lateral bending and rotation, the range of motion of model A was 5.01°, 4.03°, 3.91° and 1.42° in segment L 4/5, and was 4.62°, 2.51°, 2.40° and 1.23° in segment L 5/S 1. (2) The overall range of motion, range of motion of segment L 4/5 and L 5/S 1 and maximum overall displacement of models A, C, and D were similar in axial compression, forward flexion, backward extension, left bending, and left rotation, while those of model B were significantly increased. (3) There was no significant difference in the maximum displacement of the isthmus of models A, C, and D under different motion modes, while the maximum displacement of model B in the isthmus was significantly larger than that of models A, C, and D, especially during rotation, increased by 295%, 277%, and 276% respectively. The maximum stress of the isthmus of model C was 0.938 MPa, 1.698 MPa, 0.410 MPa, 2.775 MPa, and 1.554 MPa respectively. The maximum stress in the isthmus of model D was 0.590 MPa, 1.297 MPa, 0.520 MPa, 3.088 MPa, and 2.072 MPa respectively. The maximum stress of the isthmus of models C and D was similar during axial compression and forward flexion, while the stress of the isthmus of model C was smaller than that of model D during backward extension, lateral bending, and rotation, decreased by 21.1%, 10.2%, and 25.0% respectively compared with model D. (4) The maximum stress of internal fixation in models C and D during forward flexion, backward extension, left bending, and left rotation was 135.220 MPa, 130.180 MPa, 200.940 MPa and 306.340 MPa respectively, and was 131.840 MPa, 112.280 MPa, 349.980 MPa and 370.140 MPa respectively. The maximum stress of internal fixation in the two models of internal fixation during forward flexion and backward extension was similar, while it was decreased by 42.6% and 17.2% in model C during left bending and left rotation, compared with model D. (5) The maximum stress of the vertebral body during forward flexion, backward extension, left bending, and left rotation was 79.787 MPa, 36.857 MPa, 37.943 MPa and 96.965 MPa respectively in model C, but was 80.104 MPa, 64.236 MPa, 196.010 MPa and 193.020 MPa respectively in model D. The maximum stress of models C and D was all distributed in the contact area with the internal fixation, and especially during backward extension, left bending, and left rotation, when it was reduced by 42.6%, 80.6%, and 49.8% of model C respectively, compared with that of model D. Conclusions:The improved laminar hook is more consistent with the Chinese anatomized structure of the lamina. Compared with the traditional lamina hook system, the improved lamina hook system can effectively reduce the displacement in all directions and range of motion of lumbar spondylolysis, therefor can significantly reduce the stress of internal fixation and vertebral body and has better biomechanical performance.

Lumbar spondylolysis is one of the common diseases of low back pain caused by spinal surgery. Its treatment options vary depending on different conditions, from early conservative ones to late surgical ones. There are still disputes over various conservative treatments, choice of surgical methods and the biomechanics of different internal fixation techniques to repair spondylolysis. Therefore, this review summarizes the clinical outcomes of previous clinical treatments of lumbar spondylolysis and the biomechanical characteristics of various techniques to find the mechanical and evidence-based clinical data that may facilitate the treatment of lumbar spondylolysis.

Objective:To explore the application and effect of the online teaching in the clinical nursing practice of obstetrics and gynecology during the coronavirus disease 2019 (COVID-19) epidemic.Methods:A total of 26 undergraduate nursing interns in the obstetrics and gynecology department of Xiangya Hospital of Central South University during the epidemic period were enrolled in this study. The interns accepted online practical teaching, and the teaching effect was analyzed and evaluated through the results of the exit examination and online teaching satisfaction.Results:The theoretical course scores of nursing students are all above 80 points, among which 22 (84.62%) are above 90 points. The operation scores are all above 90 (94.04±2.96) points. The results of the online teaching satisfaction survey show that, 23 (88.46%) nursing students are satisfied with the effect of their online practice.Conclusion:The online teaching mode during COVID-19 epidemic can help nursing students master the theoretical knowledge of obstetrics and gynecology, improve their clinical reasoning ability, strengthen their practical operation skills, and enhance their autonomous learning ability.

Objective:To integrate relevant research contents and systematically evaluate the relevant factors that affect nurses' perception of hospital ethical atmosphere.Methods:PubMed, Web of Science, Embase, The Cochrane library, China Biological Medical Literature Database (CBM) , Chinese National Knowledge Infrastructure (CNKI) , Chinese Science and Technology Periodical Database (VIP) and WanFang Database (WF) were searched to collect all related researches from the establishment of the database to August 31, 2019. The quality evaluation of the included literature was carried out using the quality evaluation standards of the cross-sectional status survey research of the Australian JBI Evidence-based Health Care Center (2016) , and qualitative methods were used to integrate the literature results.Results:A total of 17 papers were included, 15 were cross-sectional studies, and 2 were qualitative studies. A total of 15 influencing factors were extracted and summarized into 3 categories, namely personal factors, occupational factors and organizational factors, including nurses' age, education level, length of service, position, workplace, organizational cooperation, and support.Conclusions:Nurses' perception of the hospital ethical atmosphere is affected by various factors. The more consistent views mainly include personnel relations, positions, type and nature of workplaces, organizational cooperation and support, but other factors such as age, length of service, education level, monthly income, work burden and so on due to differences in conclusions or insufficient literatures, the effect is not clear.In the future, more relevant studies are needed to explore the influencing factors of nurses' perception of ethical atmosphere, explore potential influencing factors and explore possible influencing mechanisms, so as to lay a theoretical foundation for formulating correct and effective intervention measures.

Objective: To explore the effect of nursing scheduling software combined with mobile phone APP in the nursing manpower arrangement in intensive care unit. Methods: The nursing scheduling software and mobile phone APP were applied to management resources of 82 nurses in ICU, substituted for traditional manual way. The work efficiency, nursing quality and nurse satisfaction were compared before and after implementing in intensive care unit. Results: After implementation of nursing scheduling software combined with mobile phone APP, the average time of scheduling was reduced from (6.49±0.62) h to (4.29±0.44) h, the difference was statistically significant (t=19.97, P<0.01). The nursing quality score was improved from (97.54±1.19) points to (95.16±1.29) points, the difference was statistically significant (t=-4.70, P<0.01). The nurses′ satisfaction about scheduling was improved from 73.2%(60/82) to 96.3%(79/82), the difference was statistically significant (χ²=17.04, P<0.01). Conclusions The mode of nursing scheduling software combined with mobile phone APP in intensive care unit has a good effect, which can improve the scheduling efficiency, the job satisfaction of nursing staff and the quality of nursing,and promote the nursing information management.

0.8.There was concurrent validity between CSS and NIHSS(r=0.86).The prognosis prediction accuracy of CSS was 92.4%,slightly lower than that of NIHSS(94.1%).Logistic regression showed that CSS's "gaze function" and "facial paralysis" were not included in the prediction equation.The facial paralysis had a SES of 0.38,all others had a SES higher than 0.5.Most fields showed a good sensitivity.Conclusion: CSS shows an acceptable reliability,validity and sensitivity in patients with stroke,but the predicative validity of CSS is inferior to that of NIHSS,which needs be further revised.