ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.

Objective:To explore the clinical characteristics and prognosis risk factors of aggressive NK-cell leukemia(ANKL).Methods:The clinical and laboratory data of 34 patients with ANKL and 15 patients with chronic lymphoproliferative disorders of NK cells(CLPD-NK)admitted to the First Affiliated Hospital of Zhengzhou University from September 2019 to December 2024 were retrospectively analyzed.The Kaplan-Meier method was used to calculate survival rates,and the Cox proportional hazards regression model was used to analyze prognostic factors.Results:Compared with CLPD-NK patients,ANKL patients had a younger median age of onset,a higher proportion patients with EBV-DNA≥500 copies/ml,hepatosplenomegaly and hemophagocytic syndrome.They also presented with a higher peak of fever,a shorter median survival time,lower WBC count,PLT count,ALB and Fib values,while having higher LDH,AST,TG,ferritin,CRP and PCT levels.There were statistically significant differences in the morphology and expression of HLA-DR,CD56,CD57,CD16 and CD158 on abnormall cells between ANKL patients and CLPD-NK patients.Multivariate survival analysis revealed that combined with asparaginase treatment could improve patients' survival,and CRP≥ 15 mg/L and Fib＜2.0 g/L were independent risk factors affecting the overall survival of patients with ANKL.Conclusion:The differences in clinical features and laboratory tests between patients with ANKL and CLPD-NK aid in the diagnosis of ANKL.CRP and Fib levels can be used to predict the prognosis of patients,and combined asparaginase therapy can enhance the overall survival of patients.

Objective:To investigate the trends in insulin resistance, as represented by the triglyceride-glucose index (TyG index), among Chinese adult residents from 2010 to 2018 and to explore influencing factors.Methods:China Chronic Disease and Risk Factor Surveillance was conducted in 2010, 2013, and 2018, using a multi-stage stratified cluster random sampling method across all 31 provinces (autonomous regions and municipalities) in China. This study sampled 98 712 adults in 2010, 176 534 adults in 2013, and 184 876 adults in 2018, all aged ≥18 years, totaling 406 933 participants. Individuals with a TyG index > P75 were classified as having insulin resistance. The mean TyG index and the prevalence of insulin resistance were calculated for different years, sexes, age groups, provinces (autonomous regions and municipalities), and subgroups for 2018. Linear and logistic regression models were used to test trends in means and rates over time, and multivariate logistic regression models were conducted to analyze potential factors associated with insulin resistance. All analyses were adjusted for complex sampling weights based on the study design. Results:From 2010 to 2018, the mean TyG index among Chinese adults increased from 8.44±0.63 to 8.70±0.64, with significant upward trends observed across different age groups, sexes, and urban-rural residencies (all P<0.001). The mean TyG index was higher among males, urban residents, and those aged 45-59. There were significant differences in the mean TyG indices and prevalence of insulin resistance across provinces (autonomous regions and municipalities) (all P<0.05). Higher insulin resistance prevalence was independently associated with being male, aged ≥45 years, living in urban areas, excessive alcohol consumption, and insufficient physical activity (all P<0.05). Conclusions:From 2010 to 2018, the level of insulin resistance, as indicated by the TyG index, showed an increasing trend among Chinese adults. Males, individuals aged ≥45 years, urban residents, and individuals with unhealthy lifestyles such as excessive alcohol consumption or insufficient physical activity should be the focus of efforts to prevent and control metabolic diseases related to insulin resistance.

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 explore the association between pre-diabetes and glomerular hyperfiltration status in residents in China.Methods:The study subjects were the non-diabetes population in China Chronic Disease and Risk Factor Surveillance in 2018. According to the definition of prediabetes, the study subjects were divided into normoglycemic and pre-diabetes groups, and multivariate factorial logistic regression model was used to analyze the association between prediabetes and the risk for glomerular hyperfiltration and glomerular filtration rate decline, respectively. Restricted cubic spline was used to explore the dose-response relationship between different glycemic indexes and the risk for glomerular hyperfiltration.Results:A total of 129 735 eligible study subjects aged 18 to 74 years were included, including 45 336 persons with prediabetes. After adjusting for confounders, the OR for glomerular hyperfiltration in the prediabetes group was 1.26 (95% CI: 1.20-1.32) compared with the normoglycemic group, and prediabetes was not associated with decreased glomerular filtration rate ( OR=1.03, 95% CI: 0.96-1.12). Age-stratified results showed a 28% increase of risk for glomerular hyperfiltration in prediabetes group compared with normoglycemic group in those aged 18-59 year ( OR=1.28, 95% CI: 1.21-1.35), and a 15% increase of risk in old adults aged 60-74 years ( OR=1.15, 95% CI: 1.05-1.25); the risk for glomerular hyperfiltration in women with prediabetes ( OR=1.38, 95% CI: 1.29-1.47) was higher than that in men with prediabetes ( OR=1.14, 95% CI: 1.06-1.22); and the risk for prediabetes glomerular hyperfiltration was higher in those with insufficient physical activity ( OR=1.29, 95% CI: 1.22-1.36) than in those who were physically active ( OR=1.16, 95% CI: 1.04-1.29). Restricted cubic spline results showed that fasting plasma glucose, glycosylated hemoglobin and glomerular hyperfiltration risk all showed U-shaped associations, and 2 hours blood glucose glomerular hyperfiltration risk after taking sugar showed an approximate J-shaped association. Conclusions:The risk for glomerular hyperfiltration exists in the prediabetes population, and prediabetes is not associated with the decrease in glomerular filtration rate. Hyperglycemia control at an early and reversible stage is important to prevent glomerular hyperfiltration developing to hypofiltration and renal impairment.

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 trends in insulin resistance, as represented by the triglyceride-glucose index (TyG index), among Chinese adult residents from 2010 to 2018 and to explore influencing factors.Methods:China Chronic Disease and Risk Factor Surveillance was conducted in 2010, 2013, and 2018, using a multi-stage stratified cluster random sampling method across all 31 provinces (autonomous regions and municipalities) in China. This study sampled 98 712 adults in 2010, 176 534 adults in 2013, and 184 876 adults in 2018, all aged ≥18 years, totaling 406 933 participants. Individuals with a TyG index > P75 were classified as having insulin resistance. The mean TyG index and the prevalence of insulin resistance were calculated for different years, sexes, age groups, provinces (autonomous regions and municipalities), and subgroups for 2018. Linear and logistic regression models were used to test trends in means and rates over time, and multivariate logistic regression models were conducted to analyze potential factors associated with insulin resistance. All analyses were adjusted for complex sampling weights based on the study design. Results:From 2010 to 2018, the mean TyG index among Chinese adults increased from 8.44±0.63 to 8.70±0.64, with significant upward trends observed across different age groups, sexes, and urban-rural residencies (all P<0.001). The mean TyG index was higher among males, urban residents, and those aged 45-59. There were significant differences in the mean TyG indices and prevalence of insulin resistance across provinces (autonomous regions and municipalities) (all P<0.05). Higher insulin resistance prevalence was independently associated with being male, aged ≥45 years, living in urban areas, excessive alcohol consumption, and insufficient physical activity (all P<0.05). Conclusions:From 2010 to 2018, the level of insulin resistance, as indicated by the TyG index, showed an increasing trend among Chinese adults. Males, individuals aged ≥45 years, urban residents, and individuals with unhealthy lifestyles such as excessive alcohol consumption or insufficient physical activity should be the focus of efforts to prevent and control metabolic diseases related to insulin resistance.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.