Objective To analyze the pollution characteristics of PM_2.5-bound polycyclic aromatic hydrocarbons (PAHs) during the non-heating period, heating period, and haze period in Harbin, and infer their possible sources, and to evaluate their impact on population carcinogenesis. Methods From 2020 to 2022, sampling points were set up in different districts of Harbin. PM_2.5 samples were regularly collected every month to analyze the contents of 10 types of PM_2.5-bound 4-6 rings PAHs. The pollution characteristics of PAHs were analyzed during different monitoring periods (non-heating period, heating period, and haze period). The excess carcinogenesis risks of PM_2.5-bound PAHs were assessed according to the Technical Specifications for Health Risk Assessment of Ambient Air Pollution and the U. S. Environmental Protection Agency (US EPA) risk assessment method. The characteristic ratio method and the positive matrix factorization (PMF) model were used to infer the sources of PAHs. Results The median mass concentrations of ambient PM_2.5-bound 4-6 rings PAHs (ΣPAHs) during the non-heating period, heating period, and haze period were 6.44 ng/m³, 37.85 ng/m³, and 106.79 ng/m³, respectively. During the heating season and haze period, the concentrations of benzo[a]anthracene, benzo[k]fluoranthene, pyrene and fluoranthene were relatively high. The excess carcinogenic risks for ASF_>16, ASF_2-16 and ASF_<2 caused by exposure to PM_2.5-bound 4-6rings PAHs during the heating season were 2.34×10^-6, 1.82×10^-6, and 0.88×10^-6, respectively, while the excess carcinogenic risks for the whole population during the heating season and haze period were 5.05×10^-6 and 1.75×10^-6, respectively. The results of the two source methods showed that the main characteristic elements during the heating season were fluoranthene, pyrene, benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[a]pyrene. According to the emission source standards, it was determined that the sources were mainly coal and biomass combustion, accompanied by traffic source emissions. Conclusion In Harbin, the PM_2.5-bound 4-6 rings PAHs during the haze period is significantly higher than that during the heating period. The pollution is mainly from coal combustion emissions, accompanied by continuous traffic source pollution. The exposure to PAHs during the heating period poses a potential carcinogenic risk to the population.

Objective:To investigate the patterns of mutation evolution in patients with acute myeloid leukemia (AML) during treatment and the possible clinical significances.Methods:A retrospective case series study was conducted. A total of 103 AML patients who were hospitalized at the Affiliated Yuebei People's Hospital of Medical College of Shantou University from November 2019 to August 2021 and underwent high-throughput next-generation sequencing (NGS) technology to detect the mutations of 128 AML-related genes in bone marrow samples were selected. Based on the NGS results, the somatic gene mutations in samples of patients collected at initial diagnosis (73 cases), complete remission (CR) (30 cases), non-remission (NR) (23 cases), and recurrence (12 cases) were analyzed, and the targeted drugs involved in the gene mutations detected in NR and recurrence samples were summarized.Results:The median age [ M ( Q1, Q3)] of onset for 103 patients was 58 (48, 66) years, including 64 males (61%) and 39 females (39%); 86 cases (83%) were primary AML, and 17 cases (17%) were secondary AML; at the initial diagnosis, 51 cases (50%) had normal karyotypes, 34 cases (33%) had abnormalities, and 18 cases (17.5%) were unknown. Compared with the CR samples, the mutation frequencies of FLT3 [29% (21/73) vs. 3% (1/30)], NPM1 [27% (20/73) vs. 3% (1/30)], NRAS [22% (16/73) vs. 3% (1/30)], and IDH2 [14% (10/73) vs. 0 (0/30)] were all higher in the initial diagnosis samples, and the differences were statistically significant (all P < 0.05); compared with the initial diagnosis sample, the median number of gene mutations in each CR sample was lower [4 (2, 5) vs. 7 (5, 9)], and the difference was statistically significant ( P < 0.001). However, there was no statistically significant difference in the median number of gene mutations in each patient between the initial diagnosis samples and the NR samples, the initial diagnosis samples and the recurrence samples, and the NR samples and the recurrence samples (all P > 0.05). Analysis of 14 patients with NGS data at initial diagnosis and CR showed that the same gene mutations could be detected at initial diagnosis and CR, such as DNAH23 (3 cases), USH2A (3 cases), etc; partial gene mutations were detected at initial diagnosis but were not detected at CR, including NRAS (5 cases), FLT3 (3 cases), ANKRD26 (3 cases), NPM1 (3 cases), ETV6 (3 cases), etc; ARID1B (1 case) and DNMT3A (1 case) were negative for mutations at initial diagnosis but positive upon reaching CR. Analysis of 14 patients with NGS data at initial diagnosis and NR showed that most gene mutations persisted at initial diagnosis and NR, such as DNMT3A (5 cases), NRAS (5 cases), KRAS (3 cases), RUNX1 (3 cases), etc; the mutant genes detected at initial diagnosis but not detected at NR included USH2A (2 cases), PCLO (2 cases), ATM (2 cases), FAT1 (2 cases), etc; partial gene mutations were not detected at initial diagnosis but were detected at NR, such as FAT1 (2 cases), TCF3 (2 cases), etc. Analysis of 5 patients with NGS data at CR and recurrence showed that some gene mutations were detected at both CR and recurrence, such as BCORL1 (1 case), ARID2 (1 case), SETD2 (1 case), VEGFC (1 case), etc; FLT1 (1 case) and GNAS (1 case) gene mutations were detected at CR but not detected at recurrence; at recurrence, some gene mutations that were not detected at CR were also detected, such as ANKRD26 (1 case), WT1 (1 case), etc. Among the 23 NR samples and 12 recurrence samples, the targets of drugs approved by US Food and Drug Administration or in clinical trials were detected in 14 (61%) and 5 (42%) samples respectively, including IDH1, IDH2, FLT3, KIT, KRAS, NRAS, SF3B1, U2AF1, and SRSF2. Conclusions:The number of gene mutations in AML patients during CR is significantly less than that at initial diagnosis, some gene mutations disappear when CR is achieved through treatment, but the majority of gene mutations persist during the treatment period, including NR and recurrence, suggesting that monitoring through NGS technology can help understand the evolution of gene mutations during AML treatment and discover the potential therapeutic targets.

Objective To explore the characteristics of military training injuries in high-altitude troops and determine the possible impact of daily diet on these training injuries in order to provide theoretical reference for scientific training and medical service support for high-altitude troops.Methods A cross-sectional scheme was adopted in this study.A self-designed Military Training Injury Questionnaire for Plateau Troops was used to survey the officers and soldiers from resident high-altitude troops in July 2024 for their training injuries,daily diet,and other situations.The obtained data were statistically analyzed.Results Among the 3 655 participants,the incidence of military training injuries was 17.87%.The subject with highest incidence was physical training(45.94%),the most common season was winter(31.39%).The most common sites of injury were waist(28.48%),knees(22.21%),and ankles(18.07%),and the most common types were sprains(28.48%),chronic fatigue injuries(18.38%)and strains(12.25%).The intake amounts of coarse grains and potatoes,bean products,aquatic products and nuts were relatively low in the daily diet of high-altitude troops.Multivariate logistic regression analysis found intake of fruit(OR=0.625,95%CI:0.508～0.768,P<0.001)and of nut(OR=0.759,95%CI:0.654～0.879,P<0.001)were correlated with the occurrence of training injury.Conclusion The occurrence pattern of military training injuries in high-altitude troops in this survey is basically consistent with that of previous reports,but the incidence rate is slightly decreased.Regular consumption of fruit and nut may be protective factors for the occurrence of training injuries.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

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 investigate the correlation between changes in the inner retinal irregularity index(IRII)af-ter macular epiretinal membrane(ERM)stripping and visual function in patients with idiopathic macular epiretinal mem-brane(IMEM).Methods A retrospective analysis was conducted on the clinical data of 134 patients(162 eyes)with IMEM who visited our hospital from March 2022 to December 2024.Based on fundus color photography and OCT findings,the patients were divided into the cellophane macular reflex(CMR)group and the preretinal macular fibrosis(PMF)group.Differences in central macular thickness(CMT),best-corrected visual acuity(BCVA),inner retinal thickness(IRT),and IRII were analyzed between the two groups.The diagnostic efficacy of these indicators for IMEM at admission was analyzed using receiver operating characteristic(ROC)curves.The differences in visual function indicators and IRII before and 3 months after ERM stripping were compared in IMEM patients.The correlation between IRII levels and visual function parameters at 3 months postoperatively was analyzed using Pearson correlation analysis.Results Among the 134 patients(162 eyes)with IMEM,93 patients(103 eyes)were in the CMR group and 41 patients(59 eyes)were in the PMF group.The CMT,IRT,and IRII were significantly lower in the CMR group than in the PMF group(all P＜0.05).The areas under the curve(AUC)for CMT,IRT,and IRII were 0.616,0.609,and 0.862,respectively(all P＜0.05).Among the 134 patients(162 eyes)with IMEM,79 patients(86 eyes,53.86％)underwent surgical treatment,and 55 patients(76 eyes,46.91％)received non-surgical treatment.Three months after surgery,the CMT,IRT,and IRII in IMEM patients were sig-nificantly lower than those before surgery(all P＜0.05).At 3 months postoperatively,CMT and IRT were significantly pos-itively correlated with IRII in IMEM patients(all P＜0.05).Conclusion CMT,IRT,and IRII all have good diagnostic ef-ficacy for IMEM staging.Moreover,IRII changes in IMEM patients who underwent macular ERM stripping are positively correlated with visual function.

Objective:Given the insufficiency of current clinical biomarkers for early diagnosis of esophageal adenocarcinoma(EAC),this study developed a panel of serum protein biomarker assays using liquid-phase chip technology and preliminarily validated the detection capabilities of these markers for EAC.Methods:Collected serum samples from 48 patients with EAC and 33 age-matched healthy controls(HC).The levels of squamous cell carcinoma antigen(SCCA),human cytokeratin 19 fragment(Cyfra21-1),hepatocyte growth factor(HGF)and IL-8 in serum were analyzed by liquid chip technology.The diagnostic efficacy of a single indicator and a combination of four indicators were evaluated by receiver operation characteristic(ROC)curve.Results:The detection ranges of SCCA,Cyfra21-1,HGF and IL-8 were 0.24～1 000 ng/ml,45.72～100 000 pg/ml,21.95～16 000 pg/ml,and 0.61～10 000 pg/ml,respectively.The liquid chip technology shows a strong correlation with clinical chemiluminescence immunoassay(r=0.949 4,P<0.000 1)and ELISA technology(r=0.955 1,P<0.000 1).Compared to the HC group,serum levels of SCCA and HGF were signifi-cantly elevated in the EAC group(P<0.01),IL-8 was significantly decreased(P<0.05),while Cyfra21-1 shows no significant difference(P>0.05).In the early EAC group,serum HGF was significantly higher than in the HC group(P<0.01).ROC curve analysis shows that among individual markers,HGF exhibits the best diagnostic efficacy for early EAC with an area under the curve(AUC)of 0.761,while the AUC for the combination of the four biomarkers was 0.857,both superior to the clinical biomarkers SCCA(AUC=0.604)and Cyfra21-1(AUC=0.515).Conclusion:Liquid chip technology is used to jointly detect SCCA,Cyfra21-1,HGF,and IL-8 in human serum.In the early diagnosis of EAC,the diagnostic efficacy of the combined use of these four biomarkers is superior to that of the commonly used clinical tumor markers SCCA and Cyfra21-1.This advantage stems from the high throughput and high sensitivity characteristics of liquid-phase chip technology.Consequently,this combined detection method holds significant clinical application and is expected to provide a more accurate and reliable tool for the early diagnosis of EAC.

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.