Objective:To study the mechanism of arsenic trioxide(ATO)combined with metformin(MET)in promoting apoptosis of leukemia cells.Methods:CCK-8 method was used to detect the viability of leukemia cell line KG1a,K562,and THP1 cells treated by ATO monotherapy,MET monotherapy,and ATO combined with MET.Flow cytometry was used to detect cell cycle and apoptosis.RT-qPCR was used to detect the mRNA expression of PI3K/Akt and LKB1/AMPK pathway-related genes.Western blot was used to detect the expression of PI3K/Akt and LKB1/AMPK pathway-related proteins and autophagy-related protein LC3B and P62.Results:Compared with the ATO monotherapy group,ATO combined with MET significantly inhibited the growth of KG1a,K562 and THP1 cells,and the difference in KG1a cells was more statistically significant.The combination of the two drugs induced KG1a cell cycle arrest,promoted apoptosis,increased the expression of autophagy-related protein LC3B and P62,up-regulated the mRNA expression levels of PI3K/Akt pathway and LKB1/AMPK pathway-related genes,as well as the expression of LKB1/AMPK pathway-related proteins,and down-regulated the expression of PI3K/Akt pathway-related proteins.Conclusion:ATO combined with MET promotes apoptosis by up-regulating LKB1/AMPK and down-regulating PI3K/Akt signaling pathway to regulate the autophagy of leukemia cells.

Objective To explore the influence of hsa_circ_0004535 on type 2 diabetes(T2DM)combined with metabolic-associated fatty liver disease(MAFLD)model mice.Methods Forty-eight healthy SPF grade Balb/c mice were selected for modeling and divided into the following groups(n=6 per group):Control group:normal feed;T2DM group:diabetes model induced by high-glucose and high-fat diet;T2DM combined MAFLD group:non-alcoholic fatty liver high-glucose and high-fat diet-induced diabetes combined with fatty liver model;T2DM combined MAFLD+hsa_circ_NC group:after 4 weeks of modeling,10 nmol hsa_circ_NC injected into the tail vein;T2DM combined MAFLD+hsa_circ_0004535 group:after 4 weeks of modeling,10 nmol circ_0004535 injected into the tail vein;T2DM combined MAFLD+miRNA_NC group:after 4 weeks of modeling,10 nmol miRNA blank control injected into the tail vein;T2DM combined MAFLD+miR-1827 agomir group:after 4 weeks of modeling,10 nmol miR-1827 agomir injected into the tail vein;and T2DM combined MAFLD+miR-1827 antagomir group:after 4 weeks of modeling,10 nmol miR-1827 antagomir injected into the tail vein.Mouse body weight was measured after the interventions and recorded weekly.Glucose and insulin tolerance tests were performed,blood lipids and liver function were measured,the liver and insulin resistance indexes were calculated,and pathological tests(hematoxylin/eosin(HE),oil red O,and Masson staining,immunohistochemistry,terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL))were performed to measure the degree of hepatic inflammation,fat deposition,and fibrosis.Results(1)Body weight,liver weight,liver index,insulin resistance index,and biochemical indexes were all significantly lower in the hsa_circ_0004535 injection group compared with the hsa_circ_NC injection group and the T2DM combined MAFLD group(both P＜0.05).(2)Steatosis vacuoles were reduced and smaller and inflammatory cell infiltration was reduced in the T2DM combined MAFLD+circ_0004535 group,as shown by HE and oil red staining.(3)TUNEL-positive cells were significantly reduced in the T2DM combined MAFLD+hsa_circ_0004535 group(P＜0.05).(4)Collagen fiber deposition was significantly reduced in the T2DM combined MAFLD+hsa_circ_0004535 group,as shown by Masson staining(P＜0.05).Conclusions The expression of hsa_circ_0004535 and miRNA-1827 play important roles in regulating lipid metabolism,insulin sensitivity,inflammatory pathways,hepatocyte apoptosis,and hepatic fibrosis-related pathways in an animal model of T2DM combined with MAFLD.

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 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 summarize the clinical features,treatment and prognosis of patients with primary central nervous system lymphoma(PCNSL)with clonal bone marrow B cells,and to explore the influence on clinical diagnosis and treatment.Methods PCNSL patients with clonal bone marrow B cells diagnosed by flow cytometry between Jan 2020 and Jul 2023 at Huashan Hospital of Fudan University were enrolled.The auxiliary examination data of these patients were collected,including complete blood count,routine biochemistry,bone marrow aspiration and biopsy,contrast-enhanced brain MRI,and whole-body PET-CT.Kaplan-Meier was used to draw the survival curve,and relevant literature was reviewed.Results A total of 223 newly diagnosed PCNSL patients were included,187 of whom completed bone marrow puncture and biopsy evaluation.We found clonal bone marrow B cells in 16 of 187 cases(8.56%)by flow cytometry.2 patients showed B lymphoma involving the bone marrow.All patients received a high-dose methotrexate based chemotherapy.The median progression free survival(PFS)of 16 patients with clonal bone marrow B cells was 11.1 months,and the median PFS of 171 patients with normal bone marrow was 12.6 months.There was no significant difference in the PFS between the two groups.Conclusion PCNSL with clonal bone marrow B cells had no specific clinical features,but bone marrow flow cytometry showed clonal B cells.High-dose methotrexate treatment regimen is effective.There was no significant difference in PFS for PCNSL patients with clonal B cells and normal findings in bone marrow.Clonal B cells in bone marrow may be caused by monoclonal B-cell lymphocytosis(MBL),lymphoma involves the bone marrow and the presence of common precursor cells.Bone marrow examination should be performed in the initial evaluation of suspected PCNSL.

Objective:To study the mechanism of arsenic trioxide(ATO)combined with metformin(MET)in promoting apoptosis of leukemia cells.Methods:CCK-8 method was used to detect the viability of leukemia cell line KG1a,K562,and THP1 cells treated by ATO monotherapy,MET monotherapy,and ATO combined with MET.Flow cytometry was used to detect cell cycle and apoptosis.RT-qPCR was used to detect the mRNA expression of PI3K/Akt and LKB1/AMPK pathway-related genes.Western blot was used to detect the expression of PI3K/Akt and LKB1/AMPK pathway-related proteins and autophagy-related protein LC3B and P62.Results:Compared with the ATO monotherapy group,ATO combined with MET significantly inhibited the growth of KG1a,K562 and THP1 cells,and the difference in KG1a cells was more statistically significant.The combination of the two drugs induced KG1a cell cycle arrest,promoted apoptosis,increased the expression of autophagy-related protein LC3B and P62,up-regulated the mRNA expression levels of PI3K/Akt pathway and LKB1/AMPK pathway-related genes,as well as the expression of LKB1/AMPK pathway-related proteins,and down-regulated the expression of PI3K/Akt pathway-related proteins.Conclusion:ATO combined with MET promotes apoptosis by up-regulating LKB1/AMPK and down-regulating PI3K/Akt signaling pathway to regulate the autophagy of leukemia cells.

Objective To explore the influence of hsa_circ_0004535 on type 2 diabetes(T2DM)combined with metabolic-associated fatty liver disease(MAFLD)model mice.Methods Forty-eight healthy SPF grade Balb/c mice were selected for modeling and divided into the following groups(n=6 per group):Control group:normal feed;T2DM group:diabetes model induced by high-glucose and high-fat diet;T2DM combined MAFLD group:non-alcoholic fatty liver high-glucose and high-fat diet-induced diabetes combined with fatty liver model;T2DM combined MAFLD+hsa_circ_NC group:after 4 weeks of modeling,10 nmol hsa_circ_NC injected into the tail vein;T2DM combined MAFLD+hsa_circ_0004535 group:after 4 weeks of modeling,10 nmol circ_0004535 injected into the tail vein;T2DM combined MAFLD+miRNA_NC group:after 4 weeks of modeling,10 nmol miRNA blank control injected into the tail vein;T2DM combined MAFLD+miR-1827 agomir group:after 4 weeks of modeling,10 nmol miR-1827 agomir injected into the tail vein;and T2DM combined MAFLD+miR-1827 antagomir group:after 4 weeks of modeling,10 nmol miR-1827 antagomir injected into the tail vein.Mouse body weight was measured after the interventions and recorded weekly.Glucose and insulin tolerance tests were performed,blood lipids and liver function were measured,the liver and insulin resistance indexes were calculated,and pathological tests(hematoxylin/eosin(HE),oil red O,and Masson staining,immunohistochemistry,terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL))were performed to measure the degree of hepatic inflammation,fat deposition,and fibrosis.Results(1)Body weight,liver weight,liver index,insulin resistance index,and biochemical indexes were all significantly lower in the hsa_circ_0004535 injection group compared with the hsa_circ_NC injection group and the T2DM combined MAFLD group(both P＜0.05).(2)Steatosis vacuoles were reduced and smaller and inflammatory cell infiltration was reduced in the T2DM combined MAFLD+circ_0004535 group,as shown by HE and oil red staining.(3)TUNEL-positive cells were significantly reduced in the T2DM combined MAFLD+hsa_circ_0004535 group(P＜0.05).(4)Collagen fiber deposition was significantly reduced in the T2DM combined MAFLD+hsa_circ_0004535 group,as shown by Masson staining(P＜0.05).Conclusions The expression of hsa_circ_0004535 and miRNA-1827 play important roles in regulating lipid metabolism,insulin sensitivity,inflammatory pathways,hepatocyte apoptosis,and hepatic fibrosis-related pathways in an animal model of T2DM combined with MAFLD.

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 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.

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.