Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

Objective To investigate the role and related mechanism of the soluble guanylate cyclase(sGC)-cGMP-protein kinase G(PKG)signaling pathway in the amelioration of isoproterenol(ISO)-induced cardiac hypertrophy in mice by aqueous extract of Curcuma kwangsiensis root tubers(GYJS).Methods 72 KM male mice were divided randomly into 6 groups:normal,model,propranolol control(40 mg/kg),and GYJS low-(1 g/kg),medium-(2 g/kg),and high-dose(4 g/kg)groups.Mice in the experimental groups were injected subcutaneously with ISO 10 mg/kg on days 1～3 and ISO 5 mg/kg on days 4～14 to establish a mouse cardiac hypertrophy model.4h after each subcutaneous injection of ISO,the mice in each group were administered the corresponding drugs orally for a dosing cycle of 14 days.The hearts were then removed and whole heart and left ventricle weight were measured.Myocardial tissue pathology was observed using hematoxylin and eosin and Masson staining,and sGC subunit beta-1(GUCY1B3)and transforming growth factor(TGF-β1)were detected by immunohistochemistry.Serum lactate dehydrogenase(LDH),creatine kinase(CK),and Nitric Oxide(NO),and myocardial superoxide dismutase(SOD)activity and malondialdehyde(MDA)content were measured using respective kits.Serum cGMP was detected by enzyme-linked immunosorbent assay and quantitative reverse transcription PCR(RT-qPCR),and atrial natriuretic peptide(ANP),brain natriuretic peptide(BNP),GUCY1B3,PKG Ⅰ,and phosphodiesterase(PDE)5A mRNA expression levels were also determined by RT-qPCR.Results Compared with the model group,whole heart and left ventricle weights were significantly reduced in mice treated with propranolol or GYJS(P＜0.001 or P＜0.0001)and myocardial hypertrophy and myocardial fibrosis were significantly reversed.All the treatments significantly elevated myocardial expression of GUCY1B3(P＜0.05 or P＜0.01)and significantly reduced expression of TGF-β1(P＜0.05 or P＜0.01).The myocardial damage markers LDH and CK were significantly reduced(P＜0.05 or P＜0.01)while NO and cGMP were significantly elevated(P＜0.05 or P＜0.01),the myocardial oxidative stress indicator MDA was significantly reduced(P＜0.05 or P＜0.01)and SOD activity was significantly increased(P＜0.05 or P＜0.01).mRNA levels of the myocardial hypertrophy markers ANP,BNP,and PDE5A were significantly reduced(P＜0.05,P＜0.01,or P＜0.001)and the mRNA levels of GUCY1B3 and PKG Ⅰ were significantly increased(P＜0.01 or P＜0.001).Conclusions GYJS may improve cardiac hypertrophy by modulating the sGC-cGMP-PKG signaling pathway.

Objective:To evaluate the accuracy of the domestic "Skywalker" surgical robot in implementing personalized lower limb alignment reconstruction scheme in total knee arthroplasty (TKA) and the short-term clinical outcome of robotic assisted TKA.Methods:From September 2020 to January 2021, the data of patients who received surgical robot assisted TKA in 5 clinical centers in China (Shanghai Ninth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Southwest Hospital affiliated to Third Military Medical University, The Affiliated Hospital of Qingdao University, The First Affiliated Hospital of Chongqing Medical University and Yantai Yuhuangding Hospital, and Shanghai Ninth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine was the group leader) were prospectively collected and retrospectively analyzed. There were 24 males and 82 females with an average age of 67.6±7.3 years, (range 45-80 years); Average body mass index 26.42±4.31 kg/m 2, all the operation were performed by "Skywalker" surgical robot system according to preoperative design based on CT. The operation time, intraoperative blood loss, hospitalization days and postoperative complications were recorded, and the imaging indexes including hip-knee-ankle (HKA), lateral distal angle of femur (LDFA) and medial proximal angle of tibia (MPTA) measured before and after the operation, implant model indexes (preoperative planning implant model and postoperative implant model) and short-term clinical efficacy indexes [Western Ontario and McMaster Universities (WOMAC) osteoarthritis index] pain score, stiffness score, joint function score, total score and SF-12 score before and 3 months after the operation) were compared. Results:The average follow-up period was 109.60±9.80 d, (range 95-143 d). The average operation time of 106 patients was 105.30±23.22 min; The average intraoperative blood loss was 141.70±58.33 ml; The average length of hospitalization was 5.82±2.80 d. One patient had ischemic stroke after operation, and one patient had abnormal liver function after operation. According to the judgment of the investigator, all of them were not related to the operation. The actual angle error is the difference between the preoperative planning angle and the postoperative measurement angle. The absolute error of 99.1% (105/106) of the HKA angle was within 3°, 90.8% (69/76) of LDFA, 98.7% (75/76) of the MPTA. In 45 patients in one center where data were available, the actual implant models used in all patients were consistent with the preoperative planning size, and there were only differences in version selection such as Asian condyle. WOMAC pain score, joint function score, total score was improved from 7.34±2.85, 25.10±9.85, 34.75±13.02 to 3.34±2.66, 14.68±9.64, 18.66±13.49 before and after operation, respectively, which were statistically significant ( P<0.001) and SF-12 physiological score and psychological score were improved form 27.24±6.42, 30.68±8.26 to 38.83±5.74, 39.36±7.85 before and after operation, respectively, which were statistically significant ( t=7.33, P<0.001; t=4.53, P=0.043). Conclusion:Domestic surgical robot system "Skywalker" can assist the surgeon to achieve accurate and personalized reconstruction of lower limb alignment and achieve satisfactory short-term clinical outcomes. The long-term clinical outcomes of personalized reconstruction and survival rate of implant still need to be further studied.

Objective To establish a method of identification of DKO mouse model of Duchenne muscular dystro-phy, and to assess the dystrophin regeneration after stem cell transplantation.Methods Heterozygous mice were mated and the resulting offspring were used to identify their genotype by SSP-PCR.The plasma creatine kinase level was measured by biochemical analyzer and histological changes in the DKO mice were analyzed using HE staining.Human umbilical cord mesenchymal stem cells were prepared and injected into the DKO mice hindlimb muscle, and dystrophin expression was de-tected by immunofluorescence staining at 2 months after injection.Results Mating of heterozygous mice generated three kinds of genotype offsprings, and 21.2%of the offsprings were identified as DKO genotype (285 bp) .DKO mice showed dystrophic symptoms, their plasma creatine kinase level was as high as 16988.52 ±617.48 IU/L, and significant histologi-cal changes including diverse myocyte sizes, numerous centrally nucleated cells and connective tissue proliferation or in-flammatory cells infiltration.Human dystrophin expression was detected in the DKO mouse hindlimb muscle at two months after injection of human umbilical cord mesenchymal stem cells.Conclusion DKO mouse genotype can be identified by SSP-PCR, and DKO mouse is an ideal animal model for studies of stem cell therapy for Duchenne muscular dystrophy.