Objective To study the mechanical properties of titanium mesh and three-dimensional(3D)-printed metal vertebral body substitutes(VBS)to provide guidance for the selection and structural optimization of artificial vertebral implants in clinical practice.Methods The equivalent elastic modulus,equivalent yield strength,and structural failure mode of titanium mesh and 3D-printed porous,truss,and topologically optimized VBS were systematically investigated using compression tests.Results The elastic modulus of the titanium mesh(2 908.73±287.39 MPa)was only lower than that of the topologically optimized VBS.However,their structural strengths and stabilities were inadequate.The yield strength of the titanium mesh(46.61±4.85 MPa)was only higher than that of the porous VBS and it was the first to yield during compression.The porous VBS was insufficient for use as the vertebral implant owing to its poor mechanical strength(18.14±0.17 MPa-25.79±0.40 MPa).The truss VBS had good elastic modulus(2 477.86±55.19 MPa-2 620.08±194.36 MPa)and strength(77.61±0.50 MPa-88.42±1.07 MPa).However,the structural stability of the truss VBS was insufficient,and instability occurred easily during compression.The topologically optimized VBS had the highest elastic modulus(3 746.28±183.80 MPa)and yield strength(177.43±3.82 MPa)among all the tested VBS types,which could provide improved security and stability for artificial vertebral implant in vivo services.Conclusions Topology optimization results in a high strength and high stability VBS design.Moreover,it provides a large design space and great safety margin to provide increased possibilities for lightweight and new material design of future artificial vertebral implants.

Additive manufacturing(3D printing)technology aligns with the direction of precision and customization in future medicine,presenting a significant opportunity for innovative development in high-end medical devices.Currently,research and industrialization of 3D printed medical devices mainly focus on nondegradable implants and degradable implants.Primary areas including metallic orthopaedic implants,polyether-ether-ketone(PEEK)bone implants,and biodegradable implants have been developed for clinical and industrial application.Recent research achievements in these areas are reviewed,with a discussion on the additive manufacturing technologies and applications for customized implants.Challenges faced by different types of implants are analyzed from technological,application,and regulatory perspectives.Furthermore,prospects and suggestions for future development are outlined.

Cholesterol is an important precursor of many endogenous molecules. Disruption of cholesterol homeostasis can cause many pathological changes, leading to liver and cardiovascular diseases. CYP1A is widely involved in cholesterol metabolic network, but its exact function has not been fully elucidated. Here, we aim to explore how CYP1A regulates cholesterol homeostasis. Our data showed that CYP1A1/2 knockout (KO) rats presented cholesterol deposition in blood and liver. The serum levels of low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and total cholesterol were significantly increased in KO rats. Further studies found that the lipogenesis pathway (LXRα-SREBP1-SCD1) of KO rats was activated, and the key protein of cholesterol ester hydrolysis (CES1) was inhibited. Importantly, lansoprazole can significantly alleviate rat hepatic lipid deposition in hypercholesterolemia models by inducing CYP1A. Our findings reveal the role of CYP1A as a potential regulator of cholesterol homeostasis and provide a new perspective for the treatment of hypercholesterolemia.

Objective Aiming at the problem of significant anisotropy in the three-dimensional ( 3D) printed polyether-ether-ketone ( PEEK) bone substitutes manufactured by material extrusion technology, taking the femur, the main load-bearing long bone of the lower limb, as an example, the biomechanical properties of the femoral model under different direction in the build chamber were evaluated by the combination of finite element analysis and in-vitro mechanical experiment. Methods A left femoral model was obtained by reconstruction from CT data. The stress and displacement of the 3D printed PEEK femur with different directions in the build chamber under five physiological postures in the human gait cycle were simulated by varying the orthogonal anisotropy mechanical properties. An in-vitro mechanical experiment was conducted to investigate the safety and stability of the femur through a 3D printed PEEK femur. Results When the long axis of the femur model was perpendicular to the building platform of the 3D printer, a better mechanical property was obtained, and the maximum von Mises stress was 46. 56 MPa, which was lower than the yield stress of PEEK, while the maximum displacement was larger than that of the natural femur under same loading condition. Therefore, the 3D printed PEEK femur met the strength requirement, but the stability needs to be improved. Conclusions The long axis is recommended to be perpendicular to the building platform when the material extrusion technology was used for the substitute of the load-bearing long bone, and the effect of its anisotropy on service performance of the substitute should be carefully considered when the 3D printing technology is used for load-bearing bone substitute.

Background: At the therapeutic doses, diclofenac sodium (DFS) has few toxic side effects on mammals. On the other hand, DFS exhibits potent toxicity against birds and the mechanisms remain ambiguous. Objectives: This paper was designed to probe the toxicity of DFS exposure on the hepatic proteome of broiler chickens. Methods: Twenty 30-day-old broiler chickens were randomized evenly into two groups (n = 10).DFS was administered orally at 10 mg/kg body weight in group A, while the chickens in group B were perfused with saline as a control. Histopathological observations, serum biochemical examinations, and quantitative real-time polymerase chain reaction were performed to assess the liver injury induced by DFS. Proteomics analysis of the liver samples was conducted using isobaric tags for relative and absolute quantification (iTRAQ) technology. Results: Ultimately, 201 differentially expressed proteins (DEPs) were obtained, of which 47 were up regulated, and 154 were down regulated. The Gene Ontology classification and Kyoto Encyclopedia of Genes and Genomes pathway analysis were conducted to screen target DEPs associated with DFS hepatotoxicity. The regulatory relationships between DEPs and signaling pathways were embodied via a protein-protein interaction network. The results showed that the DEPs enriched in multiple pathways, which might be related to the hepatotoxicity of DFS, were “protein processing in endoplasmic reticulum,” “retinol metabolism,” and “glycine, serine, and threonine metabolism.” Conclusions The hepatotoxicity of DFS on broiler chickens might be achieved by inducing the apoptosis of hepatocytes and affecting the metabolism of retinol and purine. The present study could provide molecular insights into the hepatotoxicity of DFS on broiler chickens.

Objective To determine the management of family planning technology services in Changning District of Shanghai over the past decade， and to explore the key populations and service patterns along with changing family planning policy， so as to provide evidence for further family planning services and management. Methods Based on the routine statistics， family planning surgery， management of key populations， management of surgery quality， and contraceptive counseling from 2011 through 2020 in Changning District were retrospectively reviewed. Results The number of family planning surgery， induced abortion， midtrimester induced abortion， live births， and birth to induced abortion ratio has decreased. Majority of those who received induced abortion were non-local married women， whereas those under 19 years were principally non-local unmarried ones. In total， contraceptive counseling decreased among newly married couples and in the community. Postpartum contraceptive counseling guidance remained at a low level. Furthermore， the number of IUD placements and subcutaneous implants has reduced， suggesting the acceptance of highly effective methods of contraception needs to be improved. The percentage of immediate IUD placement following induced abortion gradually increased. In addition， the percentage of high-risk family planning surgery showed a decreasing trend， however， serious surgical complications remained. Conclusion With the “universal two-child” policy， the number of family planning surgery， especially induced abortions， has decreased significantly. It warrants a demand-driven family planning services， including strengthening the multiple health education and promoting to having a second child for key populations. Moreover， we should optimize the service process， strengthen the professional training for relevant clinicians and staff， and improve the quality of services for ensuring the mother and child health.

Objective To investigate the prevalence and risk factors of injury among both primary and middle school students in Changning District， Shanghai， and to provide evidence for injury prevention. Methods In 2018， data of basic characteristics and injury-related factors were obtained through field questionnaire survey among the selected primary and middle schools （2 of each）. Results The study finally included 1 821 students， with injury incidence rate of 30.1%. Among them， the injury incidence rate for the primary schools was 32.0%， and 28.8% for the middle schools. The top three injury types were falls， sharps injuries， and blunt injuries. Age， gender， myopia， and injury-related knowledge/behaviors were significantly related to injury incidence. Conclusion Falls should still be the priority of injury prevention for primary/middle school students in Changning District. The effect of reducing injuries can be achieved by improving health education about injury-related knowledge/behaviors.

Objective To propose a quick and low-cost personalized diabetic foot modeling and insole design scheme, so as to reduce the plantar pressure accurately. Methods The foot model of the patient was constructed by scaling the model with foot feature parameters, to make biomechanical analysis on plantar pressure. By means of numerical mapping model of insole elasticity and plantar pressure, the three-dimensional (3D) personalized insole model with gradient modulus was constructed. The insole was then manufactured via 3D printing technology and used for experimental validation. Results The related mechanical parameters from finite element prediction of the foot model constructed by the scaling modeling method were close to those of the CT reconstructed model, and the maximum error was controlled within 15%. Compared with wearing the normal insole, the peak pressure of the personalized insole was effectively reduced by 20%. The time and economic cost of this simplified design was reduced by approximately 90%. Conclusions The design scheme of the diabetes insole shortens the design cycle, and the personalized insole can effectively and accurately reduce the sole pressure, and reduce the risk of foot ulcer, which provides a technical basis for the promotion of the personalized diabetes insole.

Objective To investigate the current situation of sexual and reproductive health education in Changning District high schools, and to provide theoretical basis for formulating relevant contents and forms of sexual and reproductive health services for teenagers in future. Methods A total of 459 students from 5 high schools were investigated by questionnaire from September to December 2017.The questionnaire included basic information, sexual development and satisfaction with self-gender, attitudes, behaviors, knowledge, access and needs about sexual and reproductive health. Results The subjects consisted of 223 boys (48.6%), and 236 girls (51.4%), 100% of the girls had menstruation, 9% of the boys had no spermatorrhea experience.The girls were significantly higher in proportion than the boys in their sex dissatisfaction; boys were more inclined to support marginal and sexual behavior than girls; 63.4% of boys and girls opposed premarital sexual behavior and girls were more than boys in this regard; boys were more than girls in love experience and masturbation; 52.3% of the boys and girls could understand the knowledge of sexual and reproductive health and no gender difference was found. Their knowledge of contraception is poor, in which the difference between boys and girls was obvious.Girls were more concerned about the dangers of unintended pregnancy.The knowledge of sexually transmitted diseases was generally low.Network, school education, classmates and friends private chat were the top 3 approaches (accounting for 56.9%, 52.7%, 50.5%) for them to obtain the knowledge of sexual and reproductive health; their parents generally lacked sexual and reproductive health education; the proportions of rational demand of sexual psychology, sexual health, sexual physiology (contraception, fertility), prevention of sexually transmitted diseases, sexual ethics were 53.6%, 45.5%, 42.0%, 36.2%, 45.1%, respectively and there was no significant gender difference found in them. Conclusion The attitudes towards sex related behaviors among high school students are still at a relatively conservative stage.Their awareness of contraception, injury of unintended pregnancy, knowledge of sexual transmission and so on needs to be improved.It is imperative to pay attention to gender differences in providing sexual and health education and concept guidance and to help adolescents to establish a systematic and multi-channel health education system.

Objective:To design 3D printed prosthesis in an individualized way and explore the short-term clinical efficacy of reconstruction of segmental defect after resection of bone tumor in lower extremities with 3D-printed prosthesis.Methods:From January 2017 to June 2019, 6 patients with lower limb bone tumor who met the inclusion criteria were recruited, including 3 males and 3 females, aged 8.67±1.11 years (range 6-11 years). All 6 cases were primary bone tumors, and the Enneking stages were all IIB, including 3 cases of left tibial tumors, 2 cases of right tibial tumors, and 1 case of right femoral tumor. These 3D-printed prostheses were designed based on the preoperative imaging data. The mechanical stability of the prosthesis was evaluated by three-dimensional finite element analysis. After tumor resection, the 3D-printed prosthesis was installed and fixed to reconstruct the segmental bone defect. All patients were clinically followed up and evaluated by imaging regularly after operation. The functional status was assessed by the Musculoskeletal Tumor Society (MSTS) score. Oncology results and complications were recorded in detail.Results:All operations were successfully performed, including 3 cases underwent left tibial tumor resection, 2 cases underwent right tibial tumor resection, and 1 case underwent right femoral tumor resection. The length of the bone defect after tumor resection was 18.19±3.74 cm, the average operation time was 165.83±54.17 min, and the average intraoperative bleeding was 233.33±133.33 ml. These finite element analysis data show that the overall stress of these prostheses are lower than the maximum mechanical strength of the corresponding materials. These 3D printed prostheses match well with the excision defect and meet the expected effect. There were no adverse reactions during the operation. The mean follow-up period was 16.83±7.17 months. At the last follow-up, all patients survived without tumor recurrence or metastasis. Postoperative imaging results showed that all the implants were stable without complications such as peripheral infection, aseptic loosening, prosthesis fracture. These 3D-printed prostheses composite resulted in substantial bone integration at follow-up. The average MSTS score was 83.67%±9.11%.Conclusion:The individualized 3D printed prosthesis can be used to reconstruct the bone defect after the resection of osteosarcoma in the lower extremities, and the clinical efficacy was satisfactory in the short-term follow-up.