Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

Objective:To analyze the epidemiological patterns and temporal trends of gastric cancer incidence and mortality in China and globally, and to formulate evidence-based prevention strategies.Methods:Based on the GLOBOCAN 2022 database, we evaluated gastric cancer incidence and mortality patterns stratified by sex, age group, geographic region and human development index (HDI). Simple linear regression and Spearman's correlation analysis assessed associations between HDI and age-standardized incidence rate (ASIR) or age-standardized mortality rates (ASMR). Temporal trends from 2002 to 2020 were described in selected regions, and projections of global gastric cancer burden by 2050 were estimated.Results:In 2022, there were estimated 969 000 new gastric cases and 660 000 deaths worldwide. The burden was higher in men than in women, with incidence peaking at ages 65-69 and mortality at 70-74. ASIR was weakly correlated with HDI ( r=0.261, P＜0.001), while no significant association was found between HDI and ASMR ( r=-0.005, P=0.947). China accounted for 359 000 new cases and 260 000 deaths, representing 37.0% and 39.4% of the global totals, respectively. Both ASIR (13.7/10 5) and ASMR (9.4/10 5) in China exceeded the global averages (9.2/10 5 and 6.1/10 5, respectively). Although the overall global burden is decreasing, absolute case numbers are projected to increase by 84.1% (1.78 million cases) and deaths by 91.2% (1.26 million cases) by 2050. High-HDI regions will bear greater absolute burdens, whereas low-HDI regions face steeper relative increases. In China, new cases and deaths are projected to reach 607 000 and 504 000 by 2050, rising by 69.1% and 93.8%, respectively. Conclusions:Despite a declining global trend, the burden of gastric cancer remains substantial, with notable disparities across regions, sex and age groups. Targeted strategies are urgently needed, particularly in East Asia, among males, and older populations, to mitigate the future burden.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective : To investigate the regulatory mechanism of nucleotide excision repair(NER) in hepatocellular carcinoma(HCC). Methods : Based on the expression levels of genes in the NER pathway, we performed molecular typing of HCC using the TCGA database. HCC cell lines were constructed through the knockdown of RNA binding motif protein 39(RBM39) using siRNA. HCC cell lines were constructed through the overexpression ofRBM39usingRBM39plasmid. Cells were treated with Indisulam, a reagent that induces RBM39 protein degradation. Western blot and real-time fluorescence quantitative PCR were used to detect the expression levels and changes of mRNA and protein of RBM39 and excision repair cross complementation group 1(ERCC1); flow cytometry was used to detect NER efficiency; CCK-8 assay was used to detect cell viability. Results : HCC patients were categorized into three types—C1, C2, and C3—based on NER activity, with the C3 subtype showing the highest NER activity(P<0.000 1). In the groups transfected with RBM39 siRNA or treated with Indisulam, the NER repair efficiency decreased compared to the control group(P<0.01), the cell survival rate decreased(P<0.01), and both the mRNA and protein expression of ERCC1 were reduced(P<0.01). In contrast, in the RBM39 overexpression group, the mRNA and protein expression of ERCC1 were enhanced compared to the control group(P<0.01). Conclusion RBM39 may influence NER repair efficiency by regulating ERCC1 expression in HCC.

Objective:To observe the effects of adipose-derived stem cells(ADSC)combined with acellular scaffold(AS)on the ultrastructure of dorsal root ganglion and the protein and mRNA expression levels of ciliary neurotrophic factor(CNTF),Janus kinase 2(JAK2),phosphorylated JAK2(p-JAK2),signal transducer and activator of transcription 3(STAT3)and phosphorylated STAT3(p-STAT3)in the rats with sciatic nerve injury(SNI),and to clarify the protective effect of ADSC combined with AS on dorsal root ganglion in the SNI rats and its possible mechanism.Methods:The rat ADSCs were isolated and cultured and their multidirectional differentiation potential was detected.The AS of rats was prepared,and ADSCs were injected into the AS to construct tissue-engineered nerve.A total of 36 rats were randomly divided into control group,model group,AS group,and ADSC+AS group.The rats in control group were routinely fed,and the rats in other groups were used to establish the SNI models by resecting 10 mm of right sciatic nerve.The rats in model group received no further treatment,while the rats in AS group and ADSC+AS group were bridged with AS and the constructed tissue-engineered nerve at the two ends of the injured nerve,respectively.At 6 weeks after surgery,transmission electron microscope was used to observe the ultrastructure of dorsal root ganglion of the rats in various groups;immunofluorescence method was used to detect the protein expression levels of CNTF,p-JAK2,and p-STAT3 in dorsal root ganglion of the rats;real-time fluorescence quantitative PCR(RT-qPCR)method was used to detect the mRNA expression levels of CNTF,JAK2,and STAT3 in dorsal root ganglion of the rats in various groups.Results:After 7 d of primary ADSC culture,a large number of large and long spindle-shaped cells were observed under the inverted microscope,arranged in clusters or whirlpools;red lipid droplets were observed with oil red O staining under microscope,and calcified nodules were observed with Alizarin red staining under microscope,indicating that the isolated and cultured cells had multidirectional differentiation ability.Compared with normal nerve tissue,the level of DNA in AS of rats was significantly decreased(P<0.05).Compared with control group,the nuclear membrane of dorsal root ganglion cells in model group was uneven and serrated,the number of organelles in the cytoplasm was decreased,mitochondria were swollen with broken or missing cristae and unclear structure;the CNTF protein and mRNA expression levels were significantly decreased(P<0.01),the p-JAK2 and p-STAT3 protein expression levels were significantly increased(P<0.01),and the JAK2 and STAT3 mRNA expression levels were significantly increased(P<0.01).Compared with model group,the serrated change of nuclear membrane of the dorsal root ganglion cells in AS group was significantly alleviated,the number of organelles in the cytoplasm was increased,and mitochondrial swelling was reduced;in ADSC+AS group,the nuclear membrane of dorsal root ganglion cells tended to be intact,the number of organelles was increased,and mitochondrial swelling and vacuolization were significantly reduced;the CNTF protein and mRNA expression levels in the dorsal root ganglion in AS group and ADSC+AS group were significantly increased(P<0.01),the p-JAK2 and p-STAT3 protein expression levels were significantly decreased(P<0.01),and the JAK2 and STAT3 mRNA expression levels were significantly decreased(P<0.01).Compared with AS group,the CNTF protein and mRNA expression levels in ADSC+AS group were significantly increased(P<0.05 or P<0.01),the p-JAK2 and p-STAT3 protein expression levels were significantly decreased(P<0.01),and the JAK2 and STAT3 mRNA expression levels were significantly decreased(P<0.01).Conclusion:The application of ADSC combined with AS can improve the ultrastructure of dorsal root ganglion in the SNI rats,and the mechanism may be related to the increased CNTF expression and decreased activation of the JAK2/STAT3 signaling pathway in the dorsal root ganglion by ADSC combined with AS application.

Objective Readout segmentation of long variable echo-trains diffusion weighted imaging(RESOLVE DWI)was used to analyze the difference of apparent diffusion coefficient(ADC)value in deep cerebral nucleus and its correlation with clinical characteristics in patients with Parkinson's disease(PD).Methods Clinical data of 60 patients with PD were retrospectively analyzed as PD group,and were divided in-to the tremor group(n=30)and the bradykinesia group(n=30)according to symptom type,middle-aged(≤65 years old)group(n=23)and elderly(＞65 years old)group(n=37)according to age,and 60 healthy vol-unteers were selected as the control group during the same period.ADC values were measured on the ADC map of RESOLVE DWI sequence,and the ADC values of bilateral putamen,pallidus,substantia nigra,rubra,and dentate nucleus were analyzed and their correlation with UPDRS-Ⅲ score and H&Y grading.Results Compared with the control group,the ADC values of both putamen,globus pallidus,globus pallidus,red nucleus,right substantia nigra and right dentate nucleus were increased in the PD group,the ADC values of both putamen,globus pallidus,red nucleus and right substantia nigra in the tremor group were increased,and the ADC values of right putamen,globus pallidus and bilateral red nucleus in the bradykinesia group were increased(P＜0.05).Compared with the bradykinesia group,the values of ADC in the tremor group were similar.Compared with the middle-aged group,the ADC values of right putamen,bilateral globus pallidus,left substantia nigra and left red nucleus were higher in the elderly group(P＜0.05).In the PD group,the ADC values of the right putamen,globus pallidus,and dentate nucleus were positively correlated with H&Y grade and UPDRS-Ⅲscore,and the ADC value of the left putamen was positively correlated with H&Y grade.Conclusion RE-SOLVE DWI can be used to evaluate the differences in deep gray matter nuclei in PD patients,and its ADC value may be used to evaluate and predict the severity of nuclear mass damage and motor symptoms in PD pa-tients.

Objective:To analyze the colonization rate and molecular types of Staphylococcus aureus (SA) on the tracheotomy wounds of neonates at early postoperative stage in neonatal intensive care unit (NICU). Methods:This was a case series study. Patients who were admitted and underwent tracheotomy in NICU of Beijing Children′s Hospital, Capital Medical University from January 1 st 2020 to December 31 st 2023 were enrolled. Swabs on the skin around the incision or on the nasal mucosa were collected and cultured at 24, 72 and 168 h after operation. Coagulase test and Staphytect Plus kits were used for SA identification. The nuc gene amplification and molecular types of SA were assessed by PCR. The patients were divided into SA colonization group and non-colonization group based on the presence or absence of SA colonization, and into infection group and non-infection group based on the presence or absence of infection. Demographic data, hospitalization information, colonization and infection status of SA were collected from the digital medical record system of the hospital. Differences between groups were analyzed using the independent sample t test or Fisher exact test. Results:Totally 19 patients were enrolled, among whom 13 were male. The gestation age was 39.0 (38.1, 40.0) weeks, and the birth weight was 3 150 (2 600, 3 400) g. Tracheotomy was done at 8.2 (4.1, 19.6) days after diagnosis and indication confirmed. Corrected gestational age of patients on the operation day was 43.6 (42.2, 45.4) weeks. The NICU stay time was (34.0±3.1) days. SA colonization was confirmed around the incision of 8 patients. Out of the 18 strains of colonized bacteria, 10 were methicillin-resistant Staphylococcus aureus (MRSA). The most common molecular type of MRSA was ST59-SCCmec Ⅳ-t437 strain (8 strains). A total of 10 patients presented typical clinical manifestations of bacterial infection at the lungs, 3 patients in the blood stream and 2 patients in the central nervous system. Among 10 patients with bacterial infection, 3 patients were MRSA positive by boby fluid culture and affected by the ST59-SCCmec Ⅳ-t437 strain. The infection rate was different between patients with or without SA colonization on the tracheotomy incision (7/8 vs. 3/11, P=0.020). Conclusions:The colonization rate and infection rate are high on the tracheotomy incision in neonates. The major type is MRSA, and the most common molecular strain is ST59-SCCmec Ⅳ-t437 .

Objective:To investigate the prevalence and risk factors of overweight and obesity among Chinese children aged 3-18 years from 11 provinces, antonomous regions, or municipalities.Methods:This national cross-sectional community health survey utilized a multistage stratified cluster-random sampling method to recruit 193 997 nationally representative participants from 11 provinces, autonomous regions, or municipalities between January 2017 and December 2019. All participants underwent physical examinations, and their caregivers completed questionnaires assessing participants′ dietary, lifestyle, familial, and perinatal information. Multilevel multinomial logistic regression models were employed to identify the potential risk factors.Results:The cohort comprised 193 997 children (102 178 boys, 91 819 girls),aged (10±4) years. Overall prevalence rates were 30 574(15.8%)overweight children and 17 217(8.9%) obesity children. Boys exhibited higher overweight and obesity rates than girls (17.0% (17 368/102 178) vs. 14.4% (13 206/102 178), 11.3% (11 553/91 819) vs. 6.2% (5 664/91 819), χ2=249.12,1 578.69,both P<0.001). The detection rates of obesity in Tanner stage 2 and 3 were the highest in boys and girls, with 13.4%(2 231/16 665) and 8.6%(880/10 221) respectively. Risk factors for obesity included parental overweight (paternal OR=2.34 and maternal OR=2.29), annual household income of 100 000-200 000 yuan (compared with<100 000 yuan, OR=1.04), higher paternal education (compared with below high school,high school and a college education OR=1.09,1.14), birth weight >4.0 kg (≤5 and>5 years old OR=1.74, 1.44,respectively), and western food consumption≥1 time/month (compared with<1, 1-2, 3-4,>4 times/month OR=1.36, 1.30, 1.67(≤5 years), 1.19, 1.16, 1.15 (>5 years), respectively) (all P<0.05). Conversely, coarse grain intake≥1 times/week (compared with<1 times/week, every day, 3-4, 1-2 times/week OR=0.74, 0.80, 0.71 (≤5 years), 0.75, 0.87, 0.90(>5 years), respectively, all P<0.05) was associated with reduced obesity risk. Conclusions:Obesity epidemiology in children demonstrates significant heterogeneity across age, gender, geographic regions, and pubertal stages. It is necessary to establish a personalized prevention and control strategy.