Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. 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 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Objective To explore the mechanism of mesenchymal epithelial transformation(EMT)mediated by Wnt/β-catenin signaling pathway in the inhibition of endometrial fibrosis by endometrial mesenchymal stem cells(eMSCs).Methods Eighteen female SD rats were randomly divided into Sham group,Model group and eMSCs group,with 6 rats in each group.Rats in Sham group merely had laparotomy without any treatment.A rat model of intrauterine adhesion(IUA)was established in the Model group and eMSCs group.In eMSCs group,the total a-mount of eMSCs cell suspension transplanted immediately after model injury was 0.05 ml(2×107 cells/ml)per u-terus for treatment.Three weeks later,the uterus with unilateral injury was collected for hematoxylin-eosin(HE)staining and Masson staining.Endometrial fibrosis,EMT,Wnt/β-catenin pathway protein expression were analyzed by protein blot.Results In the Model group,the structure of the uterine cavity was destroyed and the number of glands were significantly reduced with a large number of blue collagen fibers were accumulated.However,after eM-SCs treatment,the number of endometrial glands increased,and the fibrotic area decreased significantly.Compared with Sham group,the expression levels of type I collagen and α-SMA protein in Model group increased significantly(P<0.05),but decreased significantly in eMSCs group(P<0.05).In the Model group,the expressions of N-cadherin,vimentin and ZEB1 increased significantly,while the expression of E-cadherin decreased.However,in eMSCs group,the changes of protein of the above molecules were completely opposite.Compared with Sham group,the expression of β-catenin and C-myc increased in Model group(P<0.05).Compared with the Model group,the expressions of CyclinE,β-catenin and C-myc increased in eMSCs group(P<0.05).Conclusion eMSCs can promote endometrial repair in IUA rats by inhibiting EMT and endometrial fibrosis,which is partly achieved by ac-tivating Wnt/β-catenin signaling pathway.

Objective To investigate the epidemiological characteristics and mutation spectrum of monogenic diseases in Chinese population through a large-scale,multicenter carrier screening.Methods This study was conducted among a total of 33 104 participants(16 610 females)from 12 clinical centers across China.Carrier status for 223 genes was analyzed using high-throughput sequencing and different PCR methods.Results The overall combined carrier frequency was 55.58%for 197 autosomal genes and 1.84%for 26 X-linked genes in these participants.Among the 16 669 families,874 at-risk couples(5.24%)were identified.Specifically,584 couples(3.50%)were at risk for autosomal genes,306(1.84%)for X-linked genes,and 16 for both autosomal and X-linked genes.The most frequently detected autosomal at-risk genes included GJB2(autosomal recessive deafness type 1A,393 couples),HBA1/HBA2(α-thalassemia,36 couples),PAH(phenylketonuria,14 couples),and SMN1(spinal muscular atrophy,14 couples).The most frequently detected X-linked at-risk genes were G6PD(G6PD deficiency,236 couples),DMD(Duchenne muscular dystrophy,23 couples),and FMR1(fragile X syndrome,17 couples).After excluding GJB2 c.109G>A,the detection rate of at-risk couples was 3.91%(651/16 669),which was lowered to 1.72%(287/16 669)after further excluding G6PD.The theoretical incidence rate of severe monogenic birth defects was approximately 4.35‰(72.5/16 669).Screening for a battery of the top 22 most frequent genes in the at-risk couples could detect over 95%of at-risk couples,while screening for the top 54 genes further increased the detection rate to over 99%.Conclusion This study reveals the carrier frequencies of 223 monogenic genetic disorders in the Chinese population and provides evidence for carrier screening strategy development and panel design tailored to the Chinese population.In carrier testing,genetic counseling for specific genes or gene variants can be challenging,and the couples need to be informed of these difficulties before testing and provided with options for not screening these genes or gene variants.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. 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 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

ObjectiveIn kinesin-3, the neck coil correlates with the following segments to form an extended neck that contains a characteristic hinge diverse from a proline in KIF13B to a long flexible linker in KIF1A. The function of this neck hinge for controlling processive movement, however, remains unclear. MethodsWe made a series of modifications to the neck hinges of KIF13B and KIF1A and tested their movement using a single-molecule motility assay. ResultsIn KIF13B, the insertion of flexible residues before or after the proline differentially impacts the processivity or velocity, while the removal of this proline increases the both. In KIF1A, the deletion of entire flexible neck hinge merely enhances the processivity. The engineering of these hinge-truncated necks of kinesin-3 into kinesin-1 similarly boosts the processive movement of kinesin-1. ConclusionThe neck hinge in kinesin-3 controls its processive movement and proper modifications tune the motor motility, which provides a novel strategy to reshape the processive movement of kinesin motors.

Objective:To study the changes in skeletal muscle and serum nutritional indicators during concurrent chemoradiotherapy in cervical cancer patients,and to evaluate their correlation with short-term efficacy and long-term prognosis. Methods:A retrospective analysis was conducted on 114 patients with cervical cancer who underwent radical concurrent chemoradiotherapy in the Department of Oncology,Nanjing Drum Tower Hospital from February 2019 to February 2023. All patients underwent a treatment regimen comprising external beam radiation (EBRT),internal radiation,and concurrent chemotherapy. Serum nutritional data of the patients were collected before radiotherapy,one week,two weeks and five weeks after the onset of radiotherapy. CT images of the patients at the time of simulation and about five weeks after the onset of radiotherapy were imported into the Pinnacle 39.10 planning system,and the skeletal muscle index (SMI) of the third lumbar vertebra (L3) were calculated for each patients. The changes of the serum nutritional indicators of the patients prior to and post EBRT were analyzed statistically. The patients are categorized into two groups according to the baseline SMI:a sarcopenic group consisting of 35 cases and a non-sarcopenic group comprising 79 cases. The therapeutic outcomes between the two groups were compared,and logistic analysis of the relevant factors affecting the occurrence of sarcopenia during radiotherapy was conducted. The survival curves were drawn using Kaplan-Meier method and disease-free survival (DFS) between the two groups was compared using Log Rank test. We used Cox univariate and multivariate regression analysis to identify prognostic factors related to DFS. Results:The serum nutritional indicators of the patient at one week,two weeks,and five weeks after the beginning of EBRT were significantly lower than those before radiotherapy (P<0.05). The SMI from the CT images of simulation at five weeks after the onset of radiotherapy was significantly lower than that before radiotherapy (P<0.001). There was a significant correlation between hemoglobin levels prior to radiotherapy and incidence of sarcopenia during radiotherapy (P=0.046). There was no significant difference in efficacy between the two groups at the end of EBRT (P>0.05). At the end of radiotherapy,the complete response (CR) rate of the non-sarcopenia group was significantly higher than that of the sarcopenia group (P=0.040). However,the objective response rate (ORR) and disease control rate (DCR) of both groups at the end of radiotherapy were 100％. The 2-year DFS of the sarcopenia group and the non-sarcopenia group were 66.7％ and 85.5％,respectively,and the difference was statistically significant (P=0.016). Only four patients died during the 2-year follow-up,so OS was not reached. Baseline SMI,serum squamous cell antigen levels prior to radiotherapy,and degree of bone marrow suppression were three independent prognostic factors affecting DFS in the patients. Conclusion:Cervical cancer patients experience significant nutritional loss during chemoradiotherapy,and baseline SMI is significantly correlated with short-term efficacy and long-term prognosis and can serve as a predictive marker for patients with cervical cancer receiving chemoradiotherapy.

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.

Ketamine,an antagonist of the glutamate N-methyl-D-aspartate(NMDA)receptor,is cur-rently one of the most widely abused psychoactive substances.Prolonged abuse can result in damages to various systems in the body,making it crucial to investigate the regulatory mechanism of ketamine addic-tion and screening related biomarkers.In this study,zebrafish embryos/larvae were initially exposed a-cutely to ketamine.Then,a ketamine addiction model was established in 6-month-old zebrafish through conditioned place preference(CPP)experiments.The zebrafish brain transcriptome was analyzed using RNA-seq,while qPCR and Western blotting were employed to detect the expression of key genes.Results revealed significant reductions in the spontaneous tail coiling,embryo hatching rate,and survival rate of zebrafish embryos in the ketamine-treated group compared to the control group.The distance moved also decreased significantly,from 1904.2 mm in the control group to 319.0 mm in the high dose of ketamine group(300 μmol/L).Conditional positional preference experiments demonstrated that the control ze-brafish did not exhibit significant changes in activity in the CPP tank.In contrast,the ketamine-treated group increased their activity time in the light zone of the tank from 385.2 s before training to 706.4 s af-ter training,representing a 26.8％increase(***P＜0.001).This suggests a preference for ketamine stimulation in zebrafish.KEGG analysis indicated enrichment of differentially expressed genes in the neu-roactive ligand-receptor interaction pathway in the ketamine-treated samples.GSEA analysis further re-veals a significant upregulation of the glutamatergic synapse pathway(NES=1.5).In addition,compared with the control group,the mRNA levels of Grin2b and Gria2 in the ketamine group increased by 4.6 and 1.4 times,respectively,while the protein levels increased by 2.0 and 1.4 times,respectively.These findings suggest that ketamine can induce addiction in zebrafish,potentially through upregulation of the glutamatergic synaptic pathway.

Objective To investigate the epidemiological characteristics and mutation spectrum of monogenic diseases in Chinese population through a large-scale,multicenter carrier screening.Methods This study was conducted among a total of 33 104 participants(16 610 females)from 12 clinical centers across China.Carrier status for 223 genes was analyzed using high-throughput sequencing and different PCR methods.Results The overall combined carrier frequency was 55.58%for 197 autosomal genes and 1.84%for 26 X-linked genes in these participants.Among the 16 669 families,874 at-risk couples(5.24%)were identified.Specifically,584 couples(3.50%)were at risk for autosomal genes,306(1.84%)for X-linked genes,and 16 for both autosomal and X-linked genes.The most frequently detected autosomal at-risk genes included GJB2(autosomal recessive deafness type 1A,393 couples),HBA1/HBA2(α-thalassemia,36 couples),PAH(phenylketonuria,14 couples),and SMN1(spinal muscular atrophy,14 couples).The most frequently detected X-linked at-risk genes were G6PD(G6PD deficiency,236 couples),DMD(Duchenne muscular dystrophy,23 couples),and FMR1(fragile X syndrome,17 couples).After excluding GJB2 c.109G>A,the detection rate of at-risk couples was 3.91%(651/16 669),which was lowered to 1.72%(287/16 669)after further excluding G6PD.The theoretical incidence rate of severe monogenic birth defects was approximately 4.35‰(72.5/16 669).Screening for a battery of the top 22 most frequent genes in the at-risk couples could detect over 95%of at-risk couples,while screening for the top 54 genes further increased the detection rate to over 99%.Conclusion This study reveals the carrier frequencies of 223 monogenic genetic disorders in the Chinese population and provides evidence for carrier screening strategy development and panel design tailored to the Chinese population.In carrier testing,genetic counseling for specific genes or gene variants can be challenging,and the couples need to be informed of these difficulties before testing and provided with options for not screening these genes or gene variants.

Objective To investigate the associations of reproductive health indicators with lung function and chronic obstructive pulmonary disease(COPD)among women aged 40 years and above.Methods From Jul to Sep,2021,female subjects aged 40 years and above were randomly selected from the Shanghai Suburban Adult Cohort and Biobank for COPD screening.A questionnaire was used to obtain information on demographic characteristics and reproductive health indicators.Linear regression was used to analyze the effects of reproductive health indicators on forced vital capacity(FVC)and forced expiratory volume in the first second(FEV1).Logistic regression was also used to analyze the effects of reproductive health factors on FVC as a percentage of the predicted value(FVC%Pred)and FEV1%Pred as well as on COPD.Results A total of 1876 women aged 40 years and above were enrolled with mean age of(62.1±8.2)years old,among them,78.1%were menopausal,and 40.9%had been pregnant≥3 times.Multivariate analysis showed that FVC and FEV1 decreased in postmenopausal women,but menopause was not associated with a decrease in their percentage of predicted values.Pregnancies≥3 times was a risk factor for COPD(for 3 times,OR=4.92,95%CI:1.48-19.95,P<0.05;for≥4 times,OR=9.06,95%CI:2.32-41.57,P<0.01),while pregnancies of 2 times did not increase the risk of COPD.Conclusion In women aged 40 years and above,menopause is associated with poorer FVC and FEV1,and excessive pregnancy(≥3 times)is a risk factor for COPD.