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 analyze the APR triangle formed when the right hepatic vein (RHV) passed through the right anterior hepatic pedicle (RAHP) and the right posterior hepatic pedicle (RPHP) by 3D visualization technique.Methods:Clinical data of 100 subjects undergoing liver contrast-enhanced CT scan in the Second Affiliated Hospital of Harbin Medical University from September 2019 to September 2022 were retrospectively analyzed, including 57 males and 43 females, aged (53.2±13.0) years. The CT data were imported into a system for 3D image reconstruction of the liver. The intrahepatic vascular structure was observed, including the portal vein, APR triangle, the angle between the RAHP and RPHP, the distance between RHV and the vertex of angle when it crosses the angle plane of the RAHP and RPHP, the structure and branches of the right posterior branch of portal vein, and the number of branches into the APR triangle from the main trunk of the right anterior and right posterior portal vein.Results:The main type of portal vein was type A (the main portal vein was divided into left and right branches, and the right branch was further divided into right anterior branch and right posterior branch), in 86 cases (86.0%). The APR triangle was observed in 81 cases (81.0%), and the distance between the right hepatic vein and the vertex of the right anterior and right posterior hepatic pedicle was (1.70±0.36) cm, 1.00-2.00 cm was 82.7%(61/81). The angle between right anterior and right posterior hepatic pedicle was 45°-90° in 77 cases (77.0%, 77/100). In 100 subjects, the main branch of the right posterior portal vein accounted for 42.0% (42/100) of typeⅠ (bifurcation type) and 53.0% (arch type) of type Ⅱ (53/100). In 16 cases (19.8%, 16/81), the main right anterior portal vein branched into the APR triangle, with a total of 22 branches. In 9 cases (11.1%, 9/81), the main branch of the right posterior portal vein (branching type) branched into the triangle, with a total of 11 branches. There were 33 cases (40.7%, 33/81) of right posterior portal vein (arch type) main branch branching into the triangle, a total of 41 branches.Conclusion:The APR triangle, composed of the RAHP, RPHP and RHV, has an objective anatomical basis and is affected by the variants of portal vein and RHV. It is more common for the RHV to be within 1.00-2.00 cm of the vertex of the angle between the RAHP and RPHP, and the main trunk of the right anterior and right posterior branches of portal vein are less divided into the triangle, so it is relatively safe to dissect within this area.

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 association between alcohol consumption and lumbar disc herniation (LDH), so as to provide a reference for the development of prevention and treatment strategies for LDH. Methods: From May to July 2022, permanent residents aged ≥18 years from eight counties (cities/districts) in Gansu Province were selected using a multistage stratified random sampling method. Data on basic characteristics, alcohol consumption in the past 30 days, hypertension, and diabetes mellitus were collected through questionnaire surveys. LDH was determined based on imaging findings, combined with disease history or clinical symptoms. Multivariable logistic regression model was used to analyze the association between alcohol consumption and LDH, with subgroup analyses conducted by gender, age, ethnicity, and altitude of residence. Propensity score matching (PSM) was utilized for sensitivity analysis. Results: A total of 4 545 individuals were surveyed. There were 2 026 (44.58%) males and 2 519 (55.42%) females. The mean age was (44.82±15.33) years. The study participants were predominantly of Han ethnicity, with 2 598 persons accounting for 57.17%. The altitude of residence was mainly above 3 500 m, with 1 941 persons accounting for 42.71%. There were 574 alcohol drinkers, accounting for 12.63%. LDH was detected in 1 035 cases, with a detection rate of 22.77%. Multivariable logistic regression analysis showed that after adjusting for gender, age, physical activity, and hypertension, compared to non-drinking residents, alcohol-consuming residents exhibited a 27.6% reduction in the risk of LDH (OR=0.724, 95%CI: 0.544-0.963). No significant interaction effects on LDH risk were observed between alcohol consumption and gender, age, ethnicity, or altitude of residence (all Pfor interaction >0.05). The results of the sensitivity analysis indicated that compared to non-drinking residents, alcohol-consuming residents exhibited a 38.8% reduction in the risk of LDH (OR=0.612, 95%CI: 0.382-0.976). Conclusion Alcohol consumption was statistically associated with a lower risk of LDH.

Objective To investigate the prognosis of patients with negative sentinel lymph nodes(SLN)after neoadjuvant chemotherapy(NAC)for breast cancer who are exempt from axillary lymph node dissection(ALND)and evaluate its safety in clinical treatment.Methods Clinical data of 2,163 patients initially diagnosed with breast cancer and having negative SLNs after NAC were se-lected from the SEER database from 2018 to 2021.Among them,373 patients underwent only SLN biopsy(SLNB group),and 1,790 patients underwent ALND(ALND group).Propensity score matching(PSM)was used to control for confounding factors,and the Kaplan-Meier method was em-ployed to analyze the overall survival rate.Univariate and multivariate Cox regression analyses were conducted to identify prognostic factors influencing the exemption from ALND in patients with negative SLNs after NAC for breast cancer.Results Before PSM,significant differences were observed be-tween the two groups in terms of clinical tumor stage,molecular subtype,estrogen receptor(ER)sta-tus,progesterone receptor(PR)status,human epidermal growth factor receptor 2(HER-2)status,efficacy of NAC,and breast surgery method(P＜0.05).After PSM,363 patients were included in each group.Univariate Cox regression analysis after PSM revealed that age,clinical tumor stage,and ER status were associated with overall survival(OS)of patients(P＜0.05).There was no sig-nificant difference in OS between patients who underwent SLNB and those who underwent ALND(P＞0.05).Multivariate Cox regression analysis indicated that age and clinical tumor stage were independent factors influencing OS in patients with negative SLNs after NAC.Survival curve analysis after PSM showed no statistically significant difference in overall survival rate between the SLNB and ALND groups(P=0.278).Conclusion Exemption from ALND in patients with negative SLNs af-ter NAC is feasible and does not affect the overall survival rate of patients.

Bio-mineralization has emerged as a promising strategy to enhance vaccine immunogenicity. This study optimized the calcium phosphate (CaP) mineralization process of foot-and-mouth disease virus-like particles (FMD VLPs) to achieve high mineralization efficiency and scalability. Key parameters, including concentrations of Ca²⁺, HPO₄^2-, NaCl, and VLPs, as well as stirring speed, were systematically optimized. Stability of the scaled-up reaction system and immunogenicity of the mineralized vaccine were evaluated. Optimal conditions [25.50 mmol/L Ca(NO₃)₂, 15 mmol/L Na₂HPO₄, 300 mmol/L NaCl, 0.75 mg/mL VLPs, and 1 500 r/min] yielded CaP-mineralized VLPs (VLPs-CaP) with high mineralization efficiency, uniform morphology, and a favorable particle size. Scaling up the reaction by 25 folds maintained consistent mineralization efficiency and particle characteristics. Immunization in mice demonstrated that VLPs-CaP induced higher titers of specific antibodies and neutralizing antibodies than unmineralized VLPs (P < 0.05). Higher IgG2a/IgG1 ratio and enhanced IFN-γ secretion (P < 0.05) further indicated robust cellular immune responses. We establish a stable and scalable protocol for VLPs-CaP, providing a theoretical and technical foundation for developing high-efficacy VLPs-CaP vaccines.
Vaccines, Virus-Like Particle/immunology* ; Immunogenicity, Vaccine ; Calcium Phosphates/chemistry* ; Foot-and-Mouth Disease Virus ; Biomineralization ; Particle Size ; Animals ; Mice ; Antibodies, Neutralizing/blood* ; Antibodies, Viral/blood* ; Immunity, Cellular

Vaccination is a crucial strategy for the prevention and control of infectious diseases. Virus-like particles (VLPs), composed of structural proteins, have garnered significant attention as a novel type of vaccine due to their excellent safety and immunogenicity. However, similar to most vaccine antigens, VLPs exhibit insufficient thermal stability, which not only restricts the widespread application of vaccines but also increases the risk of vaccine inactivation. This study aims to enhance the stability and shelf life of VLPs derived from type A foot-and-mouth disease virus (FMDV) by employing vacuum freeze-drying technology. The optimal lyoprotectant formulation was determined through single-factor and combinatorial screening. Subsequently, the correlation between the immunogenicity of the freeze-dried vaccine and the content of FMDV VLPs was evaluated via a mouse model. The stability of FMDV VLPs before and after freeze-drying was further assessed by storing them at 4, 25, and 37 ℃ for varying time periods. Results indicated that the lyoprotectant formulation No.1, composed of 7.5% trehalose, 0.1% Tween 80, 50 mmol/L glycine, 1% sodium glutamate, and 3% polyvinylpyrrolidone (PVP), effectively preserved the content of FMDV VLPs during the vacuum freeze-drying process. The immunization trial in mice revealed that the levels of specific antibodies, immunoglobulin G1 (IgG1), interleukin-4 (IL-4), and neutralizing antibodies induced by freeze-dried FMDV VLPs were comparable to those induced by non-freeze-dried FMDV VLPs. The heat treatment results showed that the storage periods of freeze-dried FMDV VLPs at 4, 25, and 37 ℃ were significantly longer than those of non-freeze-dried FMDV VLPs. In conclusion, the selected lyoprotectant formulation effectively improved the stability of FMDV VLPs vaccines. This study provides valuable insights for enhancing the stability of novel subunit vaccines.
Freeze Drying/methods* ; Animals ; Foot-and-Mouth Disease Virus/immunology* ; Mice ; Vaccines, Virus-Like Particle/chemistry* ; Foot-and-Mouth Disease/immunology* ; Vacuum ; Drug Stability ; Mice, Inbred BALB C ; Viral Vaccines/immunology*