Objective To carry out rigid-body inverse dynamics modelling and analysis of a self-designed 6RSS parallel bio-inspired masticatory robot.Methods Firstly,the functions of kinematic variables including translational/rotational velocities and accelerations were derived for rigid-body inverse dynamics modelling.Secondly,the rigid-body inverse dynamics model was established with the Newton-Euler's law.Finally,the chewing motion trajectories of the oral health volunteers were tracked and numerical calculations were carried out in the case where the robot was subjected to a chewing reaction force.Results Numerical calculations showed that the driving torque and the constraint force of the robot peaked when the chewing reaction force was at its maximum.Conclusion The external force has a large impact on the inverse dynamics of the robot,and theoretical references are provided for the motion control and optimal design of the robot.[Chinese Medical Equipment Journal,2024,45(3):16-22]

Atherosclerosis(As)is one of the major causes of high mortality and morbidity worldwide.Chemokines and their receptors are involved in the pathogenesis of As.CXC chemokine ligand 12(CXCL12)is a mem-ber of the chemokine family,and macrophage migration inhibition factor(MIF)is a chemokine like functional chemokine,CXCL12 and MIF together play important roles in As through CXC chemokine receptor 4(CXCR4).The CXCL12-CX-CR4 bioaxis is an important chemokine/chemokine receptor axis that can regulate various biological behaviors such as cell proliferation,mobilization,differentiation,homing,and chemotaxis.Numerous studies have found that it widely affects various cells related to As and is closely related to the formation and development of As plaques.Therefore,the CXCL12/MIF-CXCR4 bioaxis is expected to become a more precise target for As treatment,and regulating the CXCL12/MIF-CXCR4 bioaxis strategy provides new ideas for the prevention and treatment of As.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Objective To investigate the health status of workers exposed to noise in a brewery in Beijing and to analyze the relationship between hearing loss and blood pressure. Methods A total of 949 noise-exposed workers in a brewery who participated in occupational health examination were selected as the investigation subjects. A survey was conducted to investigate the pure tone hearing threshold and abnormal blood pressure of the workers with different characteristics, and to analyze the relationship between the two. Results Among the noise-exposed workers, the detection rates of hearing abnormality, hypertension, and increased systolic and diastolic blood pressure were 73.55%, 52.37%, 43.84% and 46.47%, respectively. The detection rates of hearing abnormality, indicators of hypertension, high frequency hearing threshold abnormality and increased binaural high frequency hearing threshold on average in males were higher than those in females (P < 0.05). Except that there was no statistically significant difference in weighted values of the better ear’s hearing thresholds among different working age groups (P> 0.05), the detection rates of other hearing abnormality, indicators of hypertension, speech frequency hearing threshold abnormality, high frequency hearing threshold abnormality，increased binaural high frequency hearing threshold on average and the weighted value of the better ear's hearing threshold all increased or had an increasing trend with the increase of age or working years (P< 0.05). The detection rates of hypertension in the groups with high frequency hearing threshold abnormality and increased binaural high frequency hearing threshold on average were higher than those in the normal group (P＜0.05). Conclusion The noise-exposed workers in the brewery have hearing impairment, which is related to the occurrence of hypertension. It is recommended to strengthen the publicity and education on noise protection and take protective measures to reduce the occurrence of occupational noise injury.

Objective:Operational efficiency and influencing factors of China's basic medical insurance system from 2020 to 2021 is conducted to provide reference for improving the operational efficiency and optimizing the input-output relationship.Methods:The super-efficiency SBM model based on unexpected output and the Malmquist index are used to measure the static and dynamic efficiency of resident medical insurance in 31 provinces in China,and Tobit regression analysis is employed to analyze the influencing factors.Results:The overall operational efficiency of resident medical insurance still needs improvement.The operational efficiency of resident medical insurance in the central and western regions is lower than that in the eastern region,and the gap is significant.Different levels and regions have differentiated main constraints on the operational efficiency of resident medical insurance.In terms of dynamic efficiency,the total factor productivity of resident medical insurance operation shows an increasing trend,mainly due to technological progress.In terms of influencing factors,the degree of aging,the level of medical expenses and the level of medical insurance supervision have a significant impact on the operational efficiency.Suggestions:Efforts should be made to bridge regional disparities,promote the equitable development of medical insurance,reasonably control the level of medical expenses,strengthen the supervision of medical insurance funds,and implement active aging policies.

Gorham-Stout disease(GSD)is a sporadic chronic disease characterized by progressive bone dissolution,absorption,and disappearance along with lymphatic vessel infiltration in bone-marrow cavities.Although the osteolytic mechanism of GSD has been widely studied,the cause of lymphatic hyperplasia in GSD is rarely investigated.In this study,by comparing the RNA expression profile of osteoclasts(OCs)with that of OC precursors(OCPs)by RNA sequencing,we identified a new factor,semaphorin 3A(Sema3A),which is an osteoprotective factor involved in the lymphatic expansion of GSD.Compared to OCPs,OCs enhanced the growth,migration,and tube formation of lymphatic endothelial cells(LECs),in which the expression of Sema3A is low compared to that in OCPs.In the presence of recombinant Sema3A,the growth,migration,and tube formation of LECs were inhibited,further confirming the inhibitory effect of Sema3A on LECs in vitro.Using an LEC-induced GSD mouse model,the effect of Sema3A was examined by injecting lentivirus-expressing Sema3A into the tibiae in vivo.We found that the overexpression of Sema3A in tibiae suppressed the expansion of LECs and alleviated bone loss,whereas the injection of lentivirus expressing Sema3A short hairpin RNA(shRNA)into the tibiae caused GSD-like phenotypes.Histological staining further demonstrated that OCs decreased and osteocalcin increased after Sema3A lentiviral treatment,compared with the control.Based on the above results,we propose that reduced Sema3A in OCs is one of the mechanisms contributing to the pathogeneses of GSD and that expressing Sema3A represents a new approach for the treatment of GSD.

Objective To evaluate the bioequivalence and safety of ezetimibe tablets in healthy Chinese subjects.Methods The study was designed as a single-center,randomized,open-label,two-period,two-way crossover,single-dose trail.Subjects who met the enrollment criteria were randomized into fasting administration group and postprandial administration group and received a single oral dose of 10 mg of the subject presparation of ezetimibe tablets or the reference presparation per cycle.The blood concentrations of ezetimibe and ezetimibe-glucuronide conjugate were measured by high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS),and the bioequivalence of the 2 preparations was evaluated using the WinNonlin 7.0 software.Pharmacokinetic parameters were calculated to evaluate the bioequivalence of the 2 preparations.The occurrence of all adverse events was also recorded to evaluate the safety.Results The main pharmacokinetic parameters of total ezetimibe in the plasma of the test and the reference after a single fasted administration:Cmax were(118.79±35.30)and(180.79±51.78)nmol·mL-1;tmax were 1.40 and 1.04 h;t1/2 were(15.33±5.57)and(17.38±7.24)h;AUC0-t were(1 523.90±371.21)and(1 690.99±553.40)nmol·mL-1·h;AUC0-∞ were(1 608.70±441.28),(1 807.15±630.00)nmol·mL-1·h.The main pharmacokinetic parameters of total ezetimibe in plasma of test and reference after a single meal:Cmax were(269.18±82.94)and(273.93±87.78)nmol·mL-1;Tmax were 1.15 and 1.08 h;t1/2 were(22.53±16.33)and(16.02±5.84)h;AUC0_twere(1 463.37±366.03),(1 263.96±271.01)nmol·mL-1·h;AUC0-∞ were(1 639.01±466.53),(1 349.97±281.39)nmol·mL-1·h.The main pharmacokinetic parameters Cmax,AUC0-tand AUC0-∞ of the two preparations were analyzed by variance analysis after logarithmic transformation.In the fasting administration group,the 90％CI of the log-transformed geometric mean ratios were within the bioequivalent range for the remaining parameters in the fasting dosing group,except for the Cmax of ezetimibe and total ezetimibe,which were below the lower bioequivalent range.The Cmax of ezetimibe,ezetimibe-glucuronide,and total ezetimibe in the postprandial dosing group was within the equivalence range,and the 90％CI of the remaining parameters were not within the equivalence range for bioequivalence.Conclusion This test can not determine whether the test preparation and the reference preparation of ezetimibe tablets have bioequivalence,and further clinical trials are needed to verify it.

Objective: To identify the social ecological factors of individual, family, and physical environments for affecting the development of fundamental motor skills (FMS) among overweight and obese children, so as to provide a basis for the future intervention design and policy making. Methods: From March to April 2022, one public primary school was recruited from each of the 4 main urban areas in Shijiazhuang, and a total of 425 children in schools were recruited for data collection including individual, family, physical environmental factors, by using a stratified cluster random sampling approach. Test of Gross Motor Development-Third Edition (TGMD-3) was used to evaluate children s FMS. Hierarchical linear regression model was employed to analysis the associations between the 18 factors for individual, family, and physical environments, and the FMS of overweight and obese children. Results: Individual level including the child s age, gender and sleep duration, and family level including high family economic level, parental support for physical activity, and the physical activity environment surrounding the family and community were consistent predictors of movement skills ( B =0.422, -1.972, 0.014, 0.045, 1.042, 0.827, 1.898), ball skills ( B =0.858, 3.953, 0.013, 0.092, 2.141, 1.173, 1.954), and composite skills ( B =1.305, 1.915, 0.028, 0.142, 3.091, 1.962, 3.879) among overweight and obese children ( P <0.05). Furthermore, child s body mass index (BMI), moderate to vigorous physical activity, perceived motor competence, pleasure of exercise,as well as BMI and physical activity levels of their primary caregiver, were associated with different types of FMS ( P <0.05). Individual, family, and physical environmental factors had moderate to high predictive explanatory power for FMS among overweight and obese children ( 2=0.69, 0.75, 0.93, P <0.01). Conclusions The factors influencing the development of FMS in overweight and obese children are multifaceted, with individual, family, and physical environment factors all playing significant roles.Corresponding measures should be actively taken to improve FMS in overweight and obese children.

Objective This study aimed to investigate the potential relationship between urinary metals copper (Cu), arsenic (As), strontium (Sr), barium (Ba), iron (Fe), lead (Pb) and manganese (Mn) and grip strength. Methods We used linear regression models, quantile g-computation and Bayesian kernel machine regression (BKMR) to assess the relationship between metals and grip strength.Results In the multimetal linear regression, Cu (β=-2.119), As (β=-1.318), Sr (β=-2.480), Ba (β=0.781), Fe (β= 1.130) and Mn (β=-0.404) were significantly correlated with grip strength (P < 0.05). The results of the quantile g-computation showed that the risk of occurrence of grip strength reduction was -1.007 (95％ confidence interval:-1.362, -0.652; P < 0.001) when each quartile of the mixture of the seven metals was increased. Bayesian kernel function regression model analysis showed that mixtures of the seven metals had a negative overall effect on grip strength, with Cu, As and Sr being negatively associated with grip strength levels. In the total population, potential interactions were observed between As and Mn and between Cu and Mn (Pinteractions of 0.003 and 0.018, respectively).Conclusion In summary, this study suggests that combined exposure to metal mixtures is negatively associated with grip strength. Cu, Sr and As were negatively correlated with grip strength levels, and there were potential interactions between As and Mn and between Cu and Mn.

Objective:To understand the epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023.Methods:The data of this study were collected from the ARI surveillance data from 16 provinces in China from 2009 to 2023, with a total of 28 278 ARI cases included in the study. The clinical specimens from ARI cases were screened for HRSV nucleic acid from 2009 to 2023, and differences in virus detection rates among cases of different age groups, regions, and months were analyzed.Results:A total of 28 278 ARI cases were enrolled from January 2009 to September 2023. The age of the cases ranged from<1 month to 112 years, and the age M ( Q1, Q3) was 3 years (1 year, 9 years). Among them, 3 062 cases were positive for HRSV nucleic acid, with a total detection rate of 10.83%. From 2009 to 2019, the detection rate of HRSV was 9.33%, and the virus was mainly prevalent in winter and spring. During the Corona Virus Disease 2019 (COVID-19) pandemic, the detection rate of HRSV fluctuated between 6.32% and 18.67%. There was no traditional winter epidemic peak of HRSV from the end of 2022 to the beginning of 2023, and an anti-seasonal epidemic of HRSV occurred from April to May 2023. About 87.95% (2 693/3 062) of positive cases were children under 5 years old, and the difference in the detection rate of HRSV among different age groups was statistically significant ( P<0.001), showing a decreasing trend of HRSV detection rate with the increase of age ( P<0.001). Among them, the HRSV detection rate (25.69%) was highest in children under 6 months. Compared with 2009-2019, the ranking of HRSV detection rates in different age groups changed from high to low between 2020 and 2023, with the age M (Q1, Q3) of HRSV positive cases increasing from 1 year (6 months, 3 years) to 2 years (11 months, 3 years). Conclusion:Through 15 years of continuous HRSV surveillance analysis, children under 5 years old, especially infants under 6 months old, are the main high-risk population for HRSV infection. During the COVID-19 pandemic, the prevalence and patterns of HRSV in China have changed.