Objective To design a performance testing platform to evaluate the working status and performance characteristics of the ventilator proportional solenoid valve.Methods The performance testing platform had its hardware including a high-pressure gas source,a pressure regulating valve,sensors and etc,and its software designed based on PyQt5 and composed of several modules for data acquisition,parameter setting,image display,indicator computation,result output and etc.Two kinds of proportional solenoid valves(Valve 1、Valve2)were selected for static and dynamic tests to verify the performance of the platform.Results The platform developed facilitated the proportional solenoid valve to carry out accurate computation of static and dynamic indicators at real time and time domain and waveform feature extraction of sensor data by precision control and data acquisition for the proportional solenoid valve.Static tests showed that Valve 1 gained advantages over Valve 2 in static flow characteristics involving in lowered repeatability,return error and offset while enhanced stability;dynamic tests indicated Valve 2 had rapid flow variations and significant flow fluctuation impacts,Valve 1 showed smooth dynamic response changes,and Valve 2 behaved better than Valve 1 in dynamic performance.Conclusion The testing platform developed comprehensively demonstrates the performance characteristics and working performance of the ventilator proportional solenoid valve,which is of great significance to enhance the reliability and safety of the ventilator.[Chinese Medical Equipment Journal,2025,46(1):13-19]

Objective To design a performance testing platform to evaluate the working status and performance characteristics of the ventilator proportional solenoid valve.Methods The performance testing platform had its hardware including a high-pressure gas source,a pressure regulating valve,sensors and etc,and its software designed based on PyQt5 and composed of several modules for data acquisition,parameter setting,image display,indicator computation,result output and etc.Two kinds of proportional solenoid valves(Valve 1、Valve2)were selected for static and dynamic tests to verify the performance of the platform.Results The platform developed facilitated the proportional solenoid valve to carry out accurate computation of static and dynamic indicators at real time and time domain and waveform feature extraction of sensor data by precision control and data acquisition for the proportional solenoid valve.Static tests showed that Valve 1 gained advantages over Valve 2 in static flow characteristics involving in lowered repeatability,return error and offset while enhanced stability;dynamic tests indicated Valve 2 had rapid flow variations and significant flow fluctuation impacts,Valve 1 showed smooth dynamic response changes,and Valve 2 behaved better than Valve 1 in dynamic performance.Conclusion The testing platform developed comprehensively demonstrates the performance characteristics and working performance of the ventilator proportional solenoid valve,which is of great significance to enhance the reliability and safety of the ventilator.[Chinese Medical Equipment Journal,2025,46(1):13-19]

Objective·To evaluate the changes in cognitive function in overweight and obese adolescents,and explore the association between cognitive function and fibroblast growth factor 21(FGF21).Methods·A total of 175 adolescents from a senior high school in Shanghai were divided into normal weight group(n=50),overweight group(n=50)and obese group(n=75)based on their body mass index(BMI).General information,anthropometric data and laboratory testing indicators of the adolescents were collected and compared.The cognitive function of the three groups of adolescents was assessed by using the accuracy(ACC)and reaction time of Flanker task and n-back task.Enzyme-linked immunosorbent assay(ELISA)was used to detect the serum FGF21 level of the three groups of adolescents.Partial correlation analysis and multiple linear regression model were used to evaluate the correlation between cognitive task performance and anthropometric data and laboratory testing indicators.Results·Compared with the normal weight group,systolic blood pressure,diastolic blood pressure,and the levels of fasting plasma glucose,glycosylated hemoglobin and triacylglycerol in the obese group were higher(all P<0.05).Under congruent or incongruent stimulus conditions in the Flanker task,there was no significant difference in ACC between any two groups;compared with the normal weight and overweight groups,the reaction time of the adolescents in the obese group was prolonged(all P<0.05).In the n-back task,there were no significant differences in ACC between any two groups,while the obese group had longer reaction time in the 1-back and 2-back tasks compared to the normal weight and overweight groups(all P<0.05).Compared with the normal weight group,serum FGF21 levels of the adolescents in the obese group were higher(P=0.000).Partial correlation analysis showed that the reaction time of the adolescents in Flanker and n-back tasks was correlated with their BMI,body fat mass,waist circumference,waist-to-hip ratio and FGF21 level(all P<0.05).Multiple linear regression analysis further confirmed that BMI was associated with prolonged reaction time in cognitive-related behavioral tasks in the adolescents(all P<0.05),and FGF21 level was associated with ACC in the 2-back task(P=0.000)and reaction time in the incongruent stimulus condition(P=0.048).Conclusion·Overweight and obese adolescents have cognitive impairments,and BMI and serum FGF21 levels are associated with changes in their cognitive function.

Objective To establish an ultra-high performance liquid phase tandem triple quadrupole mass spectrometry method for the determination of L-synephrine in rat plasma and to study its pharmacokinetics.Methods The plasma samples were precipitated by acetonitrile vortex,centrifuged,dried by nitrogen,dissolved by mobile phase,and then analyzed.Chromatographic column:Shiseido CAPCELL PAK CR(1∶4)column(2.0 mm × 150.0 mm,5 μm),temperature:25 ℃.Mobile phase:Acetonitrile:0.1％formic acid solution(containing 10 mmoL·L-1 ammonium formate)(73∶27)with flow rate:0.3 mL·min-1 and injection volume was 2 μL.The electrospray ion source ionization and positive ion multiple reaction monitoring mode were used for mass spectrometry detection,and biological sample methodology verification was carried out according to requirements.After intragastric administration with 5 mg·kg-1 dose of L-synephrine,blood samples were collected at different time points to investigate the pharmacokinetic characteristics of L-synephrine in rats.Results L-synephrine showed a good linear relationship in the range of 2-800 ng·mL-1,the lowest limit of quantification of L-synephrine was 2 ng·mL-1.Precision,extraction recovery,matrix effect,accuracy,dilution effect and residual effect all meet the requirements all met the requirements.The main pharmacokinetic parameters:Cmax were(464.83±76.68)ng·L-1,tmax were(0.67±0.26)h,t1/2z were(1.89±0.48)h,AUC0-t were(602.26±42.25)ng·mL-1·h-1,AUC0-∞ were(612.28±41.18)ng·mL-1·h-1.Conclusion The established ultra high performance liquid chromatography-tandem triple quadrupole mass spectrometry method for the determination of L-synephrine in rat plasma is simple and rapid,and can be used for the determination of L-synephrine in plasma.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in healthcare facilities in major regions of China in 2023.Methods Clinical isolates collected from 73 hospitals across China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2023 Clinical & Laboratory Standards Institute (CLSI) breakpoints.Results A total of 445199 clinical isolates were collected in 2023,of which 29.0％ were gram-positive and 71.0％ were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species (excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi) (MRSA,MRSE and MRCNS) was 29.6％,81.9％ and 78.5％,respectively.Methicillin-resistant strains showed significantly higher resistance rates to most antimicrobial agents than methicillin-susceptible strains (MSSA,MSSE and MSCNS).Overall,92.9％ of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 91.4％ of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis had significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 93.1％ in the isolates from children and and 95.9％ in the isolates from adults.The resistance rate to carbapenems was lower than 15.0％ for most Enterobacterales species except for Klebsiella,22.5％ and 23.6％ of which were resistant to imipenem and meropenem,respectively .Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.6％ to 10.0％.The resistance rate to imipenem and meropenem was 21.9％ and 17.4％ for Pseudomonas aeruginosa,respectively,and 67.5％ and 68.1％ for Acinetobacter baumannii,respectively.Conclusions Increasing resistance to the commonly used antimicrobial agents is still observed in clinical bacterial isolates.However,the prevalence of important crabapenem-resistant organisms such as crabapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a slightly decreasing trend.This finding suggests that strengthening bacterial resistance surveillance and multidisciplinary linkage are important for preventing the occurrence and development of bacterial resistance.

Objective To construct a scientific and practical management model of the hospice and pal-liative care outpatient clinic and provide a reference for the operation and development of the outpatient clin-ic.Methods The basic framework of the whole process management model of hospice and palliative care outpa-tient clinic was determined preliminarily by literature analysis,qualitative interviews and experts group meet-ings.Two rounds of consultation were conducted among 18 experts in hospice and palliative care and medical-nursing combined outpatient service by the Delphi method.Results The questionnaire response rates of the two rounds of expert consultation were both 100%and the authority coefficients of the two rounds of expert consultation were 0.88 and 0.91,respectively.Finally,the whole process management model of hospice and palliative care out-patient clinic was constructed,which was composed of three first-level indicators including staff composition,work structure and effect evaluation,5 second-level indicators and 62 third-level indicators.Conclusion The construc-ted whole process management model is scientific,innovative and continuous,which can provide a reference for the operation and development of the hospice and palliative care outpatient clinic.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Objective To propose an evaluation and screening indicator for the reliability of emergency ventilators.Methods Firstly,a regression model was used to clean the data and remove noise to ensure the accuracy of regression analysis.Then,four groups of highly correlated data combinations,including inspiratory tidal volume-minute expiratory volume,peak airway pressure-minute expiratory volume,peak airway pressure-inspiratory tidal volume and positive end-expiratory pressure(PEEP)-mean airway pressure,were determined with the methods of curve fitting and transfer function,and the difference between the theoretical output and the actual output of the data combinations was regarded as an indicator to judge whether the ventilator functioned well or not;finally,the indicator proposed was applied to single and multiple ventilators,and the feasibility of the indicator was determined by the proportion of the ventilators functioning well.Results The evaluation results with a single ventilator showed the four groups of data combinations had the actual output fitted well with the theoretical output,and all the differences between the theoretical output and the actual output were lower than the threshold;the results with multiple ventilators indicated there were 71.49％ventilators functioning well,which was very close to the actual result that 72％ventilators behaved well.Conclusion The evaluation and screening indicator for emergency ventilators has high feasibility,and theoretical support is provided for reliability assessment and selection of series of emergency treatment equipment.[Chinese Medical Equipment Journal,2024,45(7):8-16]

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in healthcare facilities in major regions of China in 2023.Methods Clinical isolates collected from 73 hospitals across China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2023 Clinical & Laboratory Standards Institute (CLSI) breakpoints.Results A total of 445199 clinical isolates were collected in 2023,of which 29.0％ were gram-positive and 71.0％ were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species (excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi) (MRSA,MRSE and MRCNS) was 29.6％,81.9％ and 78.5％,respectively.Methicillin-resistant strains showed significantly higher resistance rates to most antimicrobial agents than methicillin-susceptible strains (MSSA,MSSE and MSCNS).Overall,92.9％ of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 91.4％ of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis had significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 93.1％ in the isolates from children and and 95.9％ in the isolates from adults.The resistance rate to carbapenems was lower than 15.0％ for most Enterobacterales species except for Klebsiella,22.5％ and 23.6％ of which were resistant to imipenem and meropenem,respectively .Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.6％ to 10.0％.The resistance rate to imipenem and meropenem was 21.9％ and 17.4％ for Pseudomonas aeruginosa,respectively,and 67.5％ and 68.1％ for Acinetobacter baumannii,respectively.Conclusions Increasing resistance to the commonly used antimicrobial agents is still observed in clinical bacterial isolates.However,the prevalence of important crabapenem-resistant organisms such as crabapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a slightly decreasing trend.This finding suggests that strengthening bacterial resistance surveillance and multidisciplinary linkage are important for preventing the occurrence and development of bacterial resistance.