Objective This study conducted molecular biological identification of the viruses carried by Culex pipiens pallens specimens collected in Shunyi District, Beijing in 2023, and observed the changes in the infection rate of the viruses carried by Cx. pipiens pallens at different collection times. Methods Cx. pipiens pallens were collected using carbon dioxide mosquito traps. The mosquito samples were ground in batches and analyzed by molecular biology technologies. The virus infection rate at different collection times was analyzed statistically. Results 17 strains of Culex pipiens pallens densovirus(CppDNV)were identified from Cx. pipiens pallens samples collected in Shunyi District, Beijing, in 2023. The nucleotide sequence analysis of the virus genome coding region showed that CppDNV was a single-stranded DNA virus with a total length of 3 335 nt, encoding 2 non-structural proteins(NS1, NS2)and 1 capsid protein(VP). The nucleotide(amino acid)sequence lengths of the three proteins were 2 376 nt(791 aa),1 092 nt(363 aa)and 1 071 nt(356 aa), respectively. Phylogenetic analysis showed that CppDNV was located in genus Brevihamaparvovirus. Statistical analysis showed no significant difference in infection rates across collection times(χ2=4.429, P=0.194). Conclusions CppDNV was identified in Cx. pipiens pallens in Beijing, and it was stably maintained in this natural population.

AIM To study the chemical constituents from Gymnema tingens Spreng.and their in vitro hypoglycemic activity.METHODS The 70％ethanol extract was isolated and purified by macroporous resin,silica gel,sephadex LH-20,and semi-preparative HPLC,then the structures of obtained compounds were identified by physicochemical propeties and spectral data.The in vitro hypoglycemic activity was evaluated by glucose uptake test in L6 cells.RESULTS Seventeen compounds were isolated and identified as 7-desoxyneocynapanogenin A(1),glaucogenin(2),cynatratoside A(3),atratcynoside F(4),(+)-lyoniresinol(5),(+)-lyoniresinol 3-O-α-D-rhamnopyranoside-(1→6)-β-D-glucopyranoside(6),fernandoside(7),3,4-dimethoxy-phenyl-1-O-β-D-apiofuranosyl-(1→2)-β-D-glucopyranoside(8),khaephuoside A(9),khaephuoside B(10),3,4,5-trimethoxy-phenyl-O-β-D-glucopyranoside(11),liquiritigenin(12),7,3'-dihydroxy-flavanone-4'-O-β-D-glucopyranoside(13),pinoresinol(14),syringaldehyde(15),(+)-1-hydroxy-pinoresinol-1-β-D-glucopyranoside(16),β-amyrin(17).Compounds 2-5、7、9、10、12、17 could promote the glucose uptake in L6 cells.CONCLUSION Compound 1 is a new compound,and 2-9、11-13、15-17 are isolated from this plant for the first time.Compounds 2-5、7、9、10、12、17 have good hypoglycemic activity.

[Purpose]To analyze the compliance and its influencing factors of lung cancer screening using low-dose computed tomography(LDCT)among high-risk population in urban districts of Chongqing from 2013 to 2021.[Methods]The lung cancer screeing of Cancer Early Diagnosis and Treatment Project was conducted among permanent residents aged 40～69 years old from 14 urban districts of Chongqing selected by cluster sampling method from 2013 to 2021.The questionnaire survey was performed to assess the risk level of lung cancer,and individuals with high risk were advised to have LDCT examination.The compliance rate of LDCT examination among high-risk populations was calculated and compared using Chi-square test among residents with different de-mographic features;the influencing factors of compliance was analyzed with generalized linear mixed models.[Results]A total of 316 066 residents completed the risk assessment questionnaire survey,52 858 people were assessed as high-risk(17.17％).Among the high-risk population,20 398 completed LDCT screening,with an overall compliance rate of 38.59％.The generalized linear mixed model showed that male participants(OR=0.871,95％CI:0.823～0.922)and smokers(light smokers:OR=0.829,95％CI:0.775～0.886;heavy smokers:OR=0.842,95％CI:0.792～0.896)had lower compliance rates;while people with higher education level(OR=1.347,95％CI:1.265～1.435),occupational exposure to harmful substances(OR=1.400,95％CI:1.340～1.463),passive smoking for 20 years or more(OR=1.472,95％CI:1.376～1.576),infrequent physical exercise(OR=1.203,95％CI:1.152～1.256),family history of lung cancer(OR=2.312,95％CI:2.201～2.429),and those having media promotion by community staff(OR=1.365,95％CI:1.223～1.524),and trained community staff(OR=1.343,95％CI:1.227～1.470)had higher compliance rates.Comorbidities were also factors influencing compliance,and there was an increasing trend of compliance rate with the increase of comorbidity numbers(P＜0.001).[Conclusion]The compli-ance rate of LDCT examination for lung cancer screening in Chongqing needs to be improved,and more precise health education should be implemented for groups with different characteristics to improve the compliance among high-risk population.

AIM To study the chemical constituents from Gymnema tingens Spreng.and their in vitro hypoglycemic activity.METHODS The 70％ethanol extract was isolated and purified by macroporous resin,silica gel,sephadex LH-20,and semi-preparative HPLC,then the structures of obtained compounds were identified by physicochemical propeties and spectral data.The in vitro hypoglycemic activity was evaluated by glucose uptake test in L6 cells.RESULTS Seventeen compounds were isolated and identified as 7-desoxyneocynapanogenin A(1),glaucogenin(2),cynatratoside A(3),atratcynoside F(4),(+)-lyoniresinol(5),(+)-lyoniresinol 3-O-α-D-rhamnopyranoside-(1→6)-β-D-glucopyranoside(6),fernandoside(7),3,4-dimethoxy-phenyl-1-O-β-D-apiofuranosyl-(1→2)-β-D-glucopyranoside(8),khaephuoside A(9),khaephuoside B(10),3,4,5-trimethoxy-phenyl-O-β-D-glucopyranoside(11),liquiritigenin(12),7,3'-dihydroxy-flavanone-4'-O-β-D-glucopyranoside(13),pinoresinol(14),syringaldehyde(15),(+)-1-hydroxy-pinoresinol-1-β-D-glucopyranoside(16),β-amyrin(17).Compounds 2-5、7、9、10、12、17 could promote the glucose uptake in L6 cells.CONCLUSION Compound 1 is a new compound,and 2-9、11-13、15-17 are isolated from this plant for the first time.Compounds 2-5、7、9、10、12、17 have good hypoglycemic activity.

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 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 significance of serum β2-microglobulin(β2-MG)for survival and relapse of patients with diffuse large B-cell lymphoma(DLBCL)in the rituximab era.Methods:Clinical data of 92 patients with DLBCL admitted from December 2003 to July 2015 were retrospectively analyzed.The optimal cutoff value of β2-MG levels for predicting prognosis of the DLBCL patients was determined using receiver operating characteristic(ROC)curve.Kaplan-Meier analysis was used to estimate progression-free survival(PFS)and overall survival(OS).Cox logistic regression analysis was used to explore potential prognostic factors associated with survival.Binary logistic regression analysis was used to analyze the relationship between various factors and relapse.Results:The most discriminative cutoff value for β2-MG level was determined to be 2.25 mg/L by the ROC curve.Subgroup analysis showed that patients in the elevated β2-MG(＞2.25 mg/L)group had significantly worse PFS(P=0.006)and a trend toward worse OS compared with those in the low β2-MG(≤2.25 mg/L)group(P=0.053).Univariate analysis showed that elevated β2-MG,age＞60 years,Ann Arbor stage Ⅲ-Ⅳ,as well as IPI score ≥ 3 were associated with worse PFS.Binary logistic regression analysis showed that age＞60 years and β2-M G＞2.25 mg/L were potential influencing factors for relapse of DLBCL patients.Conclusion:Serum β2-MG might be an important predictor for the survival and relapse of DLBCL patients in the rituximab era.

Objective To explore the reliability of the reagent burstbead for field blood transfusion compatibility testing by applying it to bloodtype detection,antibody screening and cross matching tests and conduting parallel contrast with the existing arrays.Methods A field treatment shelter was used as the testing site to simulate the scene of emergency blood transfusion for the wounded under the conditions of field blood station,and 1 358 pieces of blood samples sent to some hospital for examination before transfusion were considered as the objects.Parallel contrast tests were carried out between the reagent burstbead method and the tube method for bloodtype detection and between the reagent burstbead method and the manual polybrene method for antibody screening and cross matching.The reagent burstbead method was compared with other methods in terms of the coin-cidence rate of the bloodtype detection results,the detection rate of positive samples for antibody screening and crossmatch incompatibility.Results The reagent burstbead method and the tube method had high consistency when used for bloodtype detection,with the coincidence rate being 100％.During antibody screening and cross matching tests,the reagent burstbead method found 5 cases of antibody-positive samples leading to major crossmatch incompatibility(positive rate being 0.37％),the manual polybrene method detected 2 cases of irregular antibody-positive samples(positive rate being 0.15％),and the two methods both identified 3 cases of minor crossmatch incompatibility.Conclusion The reagent burstbead has high accuracy and reliability when applied to bloodtype detection,antibody screening and cross matching tests,and thus can be used for blood transfusion compatibility testing in field conditions.[Chinese Medical Equipment Journal,2025,46(2):39-42]