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 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.

Aim To explore the effect of Trichinella spiralis(Ts)proteins on lipopolysaccharide(LPS)-induced inflammatory response in macrophage RAW264.7 cells.Methods The inflammation model was constructed by LPSstimulating macrophages in vitro,which were divided intothe control group,Ts group(Ts 2 mg·L-1),LPSgroup(LPS 1 mg·L-1),and Ts+LPS group(Ts 2 mg·L-1+LPS 1 mg·L-1).qRT-PCR was used to detect the mRNA levels of molecular markers of macrophage polarization,inclu-ding iNOS and Arg1,and inflammatory factors,inclu-ding IL-1 β and IL-6.The protein levels of IL-1 β,IL-6 and BRD2 were detected by Western blot further.BRD2 localization was also validated by immunofluo-rescence.In order to explore whether Ts proteins played a role in inhibiting inflammation through BRD2,si-BRD2 were transfected into RAW 264.7 cells.Once a-gain,the expression levels of iNOS,Arg1,IL-1 β,and IL-6 were detected by qRT-PCR,and IL-1 β and IL-6 were also detected by Western blot.Results Com-pared with the control group,LPS promoted the expres-sion of iNOS,IL-1 β,IL-6,and BRD2,while Ts proteins intervention decreased the expression of iNOS,IL-1 β,IL-6,BRD2.After the knockdown of BRD2,Ts pro-teins further reduced the level of iNOS,while Arg1,IL-1 β and IL-6 levels were restored.Conclusion Ts pro-teins alleviate LPS-induced macrophage inflammation by regulating macrophage polarization and inhibiting BRD2.

Objective:To evaluate the survival benefit of surgical treatment for intrahepatic cholangiocarcinoma.Methods:This study is conducted based on the hepatobiliary tumor registry database. From May 2009 to December 2022,a total of 704 patients who were initially diagnosed with intrahepatic cholangiocarcinoma and underwent liver resection were consecutively enrolled at the Hepatobiliary Center of the First Affiliated Hospital of Nanjing Medical University. Among them,there were 380 males and 324 females,aged ( M(IQR)) 61(15) years(range:27 to 88 years). Twenty-six (3.7%) patients received neoadjuvant therapy before surgery. The overall survival(OS) and disease-free survival(DFS) rates were estimated by life table method, and Kaplan-Meier survival curves were plotted. Log-rank test was used to compare the survival difference among tumor-node-metastasis(TNM) staging or three periods. The OS and DFS differences among lymph node groups or adjuvant treatment groups were quantified as HR with 95% CI estimated using Cox proportional-hazards model with adjustment for prognostic factors. Results:Among the 704 patients,349 cases(49.6%) underwent major hepatectomy (≥3 segments),331(47.0%) had lymph node resection during surgery,and 524 cases(74.4%) achieved R0 resection. The morbidity of Clavien-Dindo grade Ⅲ or higher complications was 16.5%(116/704),with a mortality rate of 3.0%(21/704) within 30 days post-surgery. The median OS time was 27.1 months, and the OS rates at 1-,3-,5- and 10-year were 69.1%, 42.4%,34.1% and 24.5%,respectively. The median DFS time was 10.5 months,and the corresponding DFS rates were 46.0%,25.4%,21.9% and 16.9%,respectively. According to the 8 th edition of AJCC staging system, the 5-year survival rates for ⅠA,ⅠB,Ⅱ,ⅢA,ⅢB and Ⅳ were 68.4%, 43.2%, 30.3%,32.2%,14.0% and 0,respectively. The corresponding DFS rates were 55.8%, 28.1%,13.8%,21.2%,3.3% and 0,respectively. There were no statistically significant differences of OS or DFS between stage ⅠB and Ⅱ, stage ⅠB and ⅢA, or between stage Ⅱ and ⅢA(Log-rank test:all P>0.05),while there were significant differences of OS and DFS among other stages(Log-rank test:all P<0.05). Using Cox model with adjustment for prognostic factors, there were no statistically significant differences of OS and DFS between non-lymphadenectomy group or the biopsy-N0 group and dissection-N0 group(both P>0.05). However,the overall and disease-free survival of the biopsy-N1 group or dissection-N1 group were worse than those of dissection-N0 group(both P<0.05),with overall survival being better in dissection-N1 group than biopsy-N1 group( P=0.017). Overall survival in the period from 2019 to 2022 were significantly superior to that during the periods from 2009 to 2013 and 2014 to 2018(both P<0.01). Adjusting for prognostic factors, the disease-free and overall survival of the postoperative adjuvant therapy group were significantly better than those of the observation group in the period 2019 to 2022(both P<0.01). Conclusions:Surgery remains a milestone for achieving long-term survival for patients with intrahepatic cholangiocarcinoma. Regional lymph node dissection is required for patients with lymph node metastasis. Adjuvant therapy can significantly reduce tumor recurrence and prolong overall survival.

Aim To explore the effect of Trichinella spiralis(Ts)proteins on lipopolysaccharide(LPS)-induced inflammatory response in macrophage RAW264.7 cells.Methods The inflammation model was constructed by LPSstimulating macrophages in vitro,which were divided intothe control group,Ts group(Ts 2 mg·L-1),LPSgroup(LPS 1 mg·L-1),and Ts+LPS group(Ts 2 mg·L-1+LPS 1 mg·L-1).qRT-PCR was used to detect the mRNA levels of molecular markers of macrophage polarization,inclu-ding iNOS and Arg1,and inflammatory factors,inclu-ding IL-1 β and IL-6.The protein levels of IL-1 β,IL-6 and BRD2 were detected by Western blot further.BRD2 localization was also validated by immunofluo-rescence.In order to explore whether Ts proteins played a role in inhibiting inflammation through BRD2,si-BRD2 were transfected into RAW 264.7 cells.Once a-gain,the expression levels of iNOS,Arg1,IL-1 β,and IL-6 were detected by qRT-PCR,and IL-1 β and IL-6 were also detected by Western blot.Results Com-pared with the control group,LPS promoted the expres-sion of iNOS,IL-1 β,IL-6,and BRD2,while Ts proteins intervention decreased the expression of iNOS,IL-1 β,IL-6,BRD2.After the knockdown of BRD2,Ts pro-teins further reduced the level of iNOS,while Arg1,IL-1 β and IL-6 levels were restored.Conclusion Ts pro-teins alleviate LPS-induced macrophage inflammation by regulating macrophage polarization and inhibiting BRD2.

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 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.

Dipsaci Radix is a commonly used Chinese herbal medicine in China, with triterpenoid saponins as the main active components. β-Amyrin synthase, a member of the oxidosqualene cyclase superfamily, plays a crucial role in the biosynthesis of oleanane-type triterpenoid saponins. Asperosaponin Ⅵ is an oleanane-type triterpenoid saponin. To explore the β-amyrin synthase genes involved in the biosynthesis of asperosaponin Ⅵ in Dipsacus asper, this study screened the candidate genes from the transcriptome data of D. asper. Two β-amyrin synthase genes, Da OSC1 and Da OSC2, were identified by phylogenetic analysis and correlation analysis. The coding sequences of Da OSC1 and Da OSC2 were 2 286 bp and 2 295 bp in length, encoding 761 and 764 amino acids,respectively. Multiple sequence alignments showed that Da OSC1 and Da OSC2 had three conserved motifs( DCTAE, QW, and MWCYCR) unique to the oxidosqualene cyclase family. Real-time quantitative PCR results showed that Da OSC1 and Da OSC2 had the highest expression levels in the roots. Compared with normal growth conditions, the low-temperature treatment significantly upregulated the expression of Da OSC1 and Da OSC2. Agrobacterium-mediated transient expression of Da OSC1 and Da OSC2 in Nicotiana benthamiana resulted in the production of β-amyrin, which suggested that Da OSC1 and Da OSC2 were able to catalyze the synthesis of β-amyrin. This study clarified the catalytic functions of two β-amyrin synthases in D. asper, analyzed their expression patterns in different tissue and at low temperatures. The findings provide a foundation for further studying the biosynthetic pathway and regulatory mechanism of asperosaponin Ⅵ in D. asper.
Intramolecular Transferases/chemistry* ; Phylogeny ; Plant Proteins/chemistry* ; Gene Expression Regulation, Plant ; Dipsacaceae/classification* ; Saponins/metabolism* ; Oleanolic Acid/metabolism*