Objective To establish a flow cytometry method for detecting C1s protein on platelet surface and preliminarily explore its potential application value in the auxiliary diagnosis of primary immune thrombocytopenia(ITP).Methods C1s-conjugated 2 μm car-boxylated magnetic beads(C1s beads)were prepared and used as quality control particles.Fluorescein isothiocyanate(FITC)-labeled anti-C1s antibody was employed as the detection antibody to develop a flow cytometric assay for detecting C1s protein expression on platelets.The intra-assay and inter-assay precision,as well as the dilution linearity of the method,were evaluated.Subsequently,the expression levels of C1 s protein on the surface of platelets were compared among the ITP group,the non-ITP thrombocytopenia group,and the healthy control group.Results Light microscopy showed that both unconjugated carboxylated magnetic beads(blank beads)and C1s-conjugated beads were uniformly dispersed without aggregation.Under fluorescence microscopy,C1s beads exhibited strong yellow-green fluorescence,whereas the blank beads showed no fluorescence signal.The established flow cytometry assay exhibited ac-ceptable precision,with intra-assay coefficient of variation(CV)values of 7.02％,7.12％,and 3.91％for low,medium,and high con-centrations of C1s beads,respectively,and inter-assay CV values of 13.49％,6.15％,and 0.78％,respectively.The dilution linearity was satisfactory,coefficient of determination(R2)=0.998 8.Clinical sample testing revealed that the proportion of C1s-positive plate-lets in ITP group(2.56±0.79)％was significantly higher than that in healthy control group(0.23±0.18)％and the non-ITP thrombo-cytopenia control group(0.22±0.10)％,with statistically significant differences(both P＜0.05).Conclusion This study successfully established a stable and reliable flow-cytometry method for quantifying C1s expression on platelet surface and preliminarily demonstrated that C1s expression is significantly elevated on platelets of ITP patients,suggesting that C1s could serve as a potential auxiliary diag-nostic marker for ITP.

Objective:To assess the relationship between basophil levels and mortality in patients with intra-abdominal infection.Methods:Information on patients with intraperitoneal infection admitted to the intensive care unit were extracted from the MIMIC database.A time-dependent Cox regression model was used to adjust for confounders associated with 28-day mortality.Propensity score matching(PSM)was used to balance the baseline differences be-tween groups with different basophil levels,and a restricted cube chart(RCS)was used to show the relationship between basophil count and 28-day mortality in patients with intra-abdominal infection.Results:A total of 4403 patients with intra-abdominal infection were enrolled in the MIMIC database.Patients with high basophil levels have lower mortality than those with low basophil levels.There was an L-shaped curve between basophil level and 28-day mortality,with a cut-off value of 0.47×109/L.Cox regression analysis showed that basophil levels were an independent protective factor for mortal-ity in patients with intra-abdominal infection after adjusting for potential confounders(HR=0.586,95%CI:0.443-0.769).Protective factors for death at basophil levels remained after PSM adjusted for potential confounders(HR=0.628,95%CI:0.470-0.832).Conclusion:Basophil level is an independent protective factor for mortality in patients with intra-abdominal infection,and basophil levels should be dynamically monitored to better evaluate the prognosis of 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 assess the relationship between basophil levels and mortality in patients with intra-abdominal infection.Methods:Information on patients with intraperitoneal infection admitted to the intensive care unit were extracted from the MIMIC database.A time-dependent Cox regression model was used to adjust for confounders associated with 28-day mortality.Propensity score matching(PSM)was used to balance the baseline differences be-tween groups with different basophil levels,and a restricted cube chart(RCS)was used to show the relationship between basophil count and 28-day mortality in patients with intra-abdominal infection.Results:A total of 4403 patients with intra-abdominal infection were enrolled in the MIMIC database.Patients with high basophil levels have lower mortality than those with low basophil levels.There was an L-shaped curve between basophil level and 28-day mortality,with a cut-off value of 0.47×109/L.Cox regression analysis showed that basophil levels were an independent protective factor for mortal-ity in patients with intra-abdominal infection after adjusting for potential confounders(HR=0.586,95%CI:0.443-0.769).Protective factors for death at basophil levels remained after PSM adjusted for potential confounders(HR=0.628,95%CI:0.470-0.832).Conclusion:Basophil level is an independent protective factor for mortality in patients with intra-abdominal infection,and basophil levels should be dynamically monitored to better evaluate the prognosis of 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.

Aim To investigate the role of triggering receptor expressed on myeloidcells 2(TREM2)in syn-aptic plasticity induced by cocaine addiction.Methods C57BL/6J mice and Trem2 knockout mice were uti-lized in this study to evaluate the alterations in postsyn-aptic density protein 95(PSD-95)and synapsin 1(SYN1)within the cortex and hippocampus of co-caine-addicted mice by using immunological tech-niques.Results HE staining and Nissl staining showed increased neuronal damage in the hippocampus and cortex of mice after cocaine addiction.The results of immunohistochemistry and fluorescence of PSD-95 and SYN1 were consistent with the expression trend of Western blot.In the wild type mouse model,the ex-pression level of PSD-95 in the hippocampus and cortex was lower than that in the saline group,and the ex-pression of SYN1 was higher than that in the saline group.In the knockout mouse model,the expression levels of PSD-95 and SYN1 in the hippocampus and cortex were significantly higher than those in the saline group after cocaine addiction.The expression levels of PSD-95 and SYN1 in the hippocampus and cortex of cocaine knockout mice were higher than those of co-caine wild type mice.Conclusion Cocaine addiction can change the synaptic plasticity,and TREM2 plays a regulatory role in the synaptic plasticity of hippocampus and cortex in mice with cocaine injury.TREM2 is ex-pected to be a new target for studying the mechanism of cocaine addiction.

Objective:To investigate the effects of Japan tallow(JT)on liver injury and gut microbiota regulation in type 2 diabetes mellitus(T2DM)mice,thereby providing a theoretical basis for developing therapeutic edible oils for diabetes treatment.Methods:T2DM animal model was established through a combined approach of nutritional intervention and chemical induction.Experimental animals were first fed a high-fat diet(HFD)for 6 weeks,followed by intraperitoneal injection of freshly prepared streptozotocin(STZ).After successful model establishment,the mice were divided into five groups(n=6 per group):control group without any intervention;T2DM group;HFD reversion to standard chow group;metformin group;and JT intervention group,which received respective treatments for 4 weeks.At the endpoint,fresh fecal samples were collected from all groups,and the gut microbiota composition was analyzed using 16s rDNA high-throughput sequencing.Liver histopathological changes were examined using histological methods.Results:Compared with the normal control(ND),T2DM mice showed significantly increased fasting blood glucose(FBG)levels,with evident hepatocyte lipid accumulation,steatosis,inflammatory cell infiltration,and widespread vacuolar and fatty degeneration.After Japan tallow(JT)intervention,FBG levels decreased significantly,liver color approximated normal appearance,and pathological morphology improved noticeably.16s rDNA sequencing analysis demonstrated that JT treatment could effectively regulate the intestinal microbiota structure in T2DM mice.Increased microbial α-diversity indices(Chao1,observed_species,Faith_pd,Simpson);At the phylum level,increased Verrucomicrobia abundance while decreased Proteobacteria were detected;At the family level,elevated Bifidobacteriaceae and reduced Porphyromonadaceae were seen;At the genus level,Bifidobacterium was promoted and Akkermansia proliferat while Escherichia and Klebsiella were downregulated.Conclusions:Japan tallow exhibits significant effects in alleviating liver tissue damage and regulating intestinal microbiota disorders in T2DM mice,our study indicated new theoretical basis for the research and development of potential strategy for diabetes.

Objective:To investigate the effects of Japan tallow(JT)on liver injury and gut microbiota regulation in type 2 diabetes mellitus(T2DM)mice,thereby providing a theoretical basis for developing therapeutic edible oils for diabetes treatment.Methods:T2DM animal model was established through a combined approach of nutritional intervention and chemical induction.Experimental animals were first fed a high-fat diet(HFD)for 6 weeks,followed by intraperitoneal injection of freshly prepared streptozotocin(STZ).After successful model establishment,the mice were divided into five groups(n=6 per group):control group without any intervention;T2DM group;HFD reversion to standard chow group;metformin group;and JT intervention group,which received respective treatments for 4 weeks.At the endpoint,fresh fecal samples were collected from all groups,and the gut microbiota composition was analyzed using 16s rDNA high-throughput sequencing.Liver histopathological changes were examined using histological methods.Results:Compared with the normal control(ND),T2DM mice showed significantly increased fasting blood glucose(FBG)levels,with evident hepatocyte lipid accumulation,steatosis,inflammatory cell infiltration,and widespread vacuolar and fatty degeneration.After Japan tallow(JT)intervention,FBG levels decreased significantly,liver color approximated normal appearance,and pathological morphology improved noticeably.16s rDNA sequencing analysis demonstrated that JT treatment could effectively regulate the intestinal microbiota structure in T2DM mice.Increased microbial α-diversity indices(Chao1,observed_species,Faith_pd,Simpson);At the phylum level,increased Verrucomicrobia abundance while decreased Proteobacteria were detected;At the family level,elevated Bifidobacteriaceae and reduced Porphyromonadaceae were seen;At the genus level,Bifidobacterium was promoted and Akkermansia proliferat while Escherichia and Klebsiella were downregulated.Conclusions:Japan tallow exhibits significant effects in alleviating liver tissue damage and regulating intestinal microbiota disorders in T2DM mice,our study indicated new theoretical basis for the research and development of potential strategy for diabetes.