Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.

Objective To examine the changing antimicrobial resistance profile of Enterobacter spp.isolates in 53 hospitals across China from 2015 t0 2021.Methods The clinical isolates of Enterobacter spp.were collected from 53 hospitals across China during 2015-2021 and tested for antimicrobial susceptibility using Kirby-Bauer method or automated testing systems according to the CHINET unified protocol.The results were interpreted according to the breakpoints issued by the Clinical & Laboratory Standards Institute(CLSI)in 2021(M100 31st edition)and analyzed with WHONET 5.6 software.Results A total of 37 966 Enterobacter strains were isolated from 2015 to 2021.The proportion of Enterobacter isolates among all clinical isolates showed a fluctuating trend over the 7-year period,overall 2.5％in all clinical isolates amd 5.7％in Enterobacterale strains.The most frequently isolated Enterobacter species was Enterobacter cloacae,accounting for 93.7％(35 571/37 966).The strains were mainly isolated from respiratory specimens(44.4±4.6)％,followed by secretions/pus(16.4±2.3)％and urine(16.0±0.9)％.The strains from respiratory samples decreased slightly,while those from sterile body fluids increased over the 7-year period.The Enterobacter strains were mainly isolated from inpatients(92.9％),and only(7.1±0.8)％of the strains were isolated from outpatients and emergency patients.The patients in surgical wards contributed the highest number of isolates(24.4±2.9)％compared to the inpatients in any other departement.Overall,≤ 7.9％of the E.cloacae strains were resistant to amikacin,tigecycline,polymyxin B,imipenem or meropenem,while ≤5.6％of the Enterobacter asburiae strains were resistant to these antimicrobial agents.E.asburiae showed higher resistance rate to polymyxin B than E.cloacae(19.7％vs 3.9％).Overall,≤8.1％of the Enterobacter gergoviae strains were resistant to tigecycline,amikacin,meropenem,or imipenem,while 10.5％of these strains were resistant to polycolistin B.The overall prevalence of carbapenem-resistant Enterobacter was 10.0％over the 7-year period,but showing an upward trend.The resistance profiles of Enterobacter isolates varied with the department from which they were isolated and whether the patient is an adult or a child.The prevalence of carbapenem-resistant E.cloacae was the highest in the E.cloacae isolates from ICU patients.Conclusions The results of the CHINET Antimicrobial Resistance Surveillance Program indicate that the proportion of Enterobacter strains in all clinical isolates fluctuates slightly over the 7-year period from 2015 to 2021.The Enterobacter strains showed increasing resistance to multiple antimicrobial drugs,especially carbapenems over the 7-year period.

Objective To understand the changing distribution and antimicrobial resistance profiles of Proteus,Morganella and Providencia in hospitals across China from January 1,2015 to December 31,2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods Antimicrobial susceptibility testing was carried out following the unified CHINET protocol.The results were interpreted in accordance with the breakpoints in the 2021 Clinical & Laboratory Standards Institute(CLSI)M100(31 st Edition).Results A total of 32 433 Enterobacterales strains were isolated during the 7-year period,including 24 160 strains of Proteus,6 704 strains of Morganella,and 1 569 strains of Providencia.The overall number of these Enterobacterales isolates increased significantly over the 7-year period.The top 3 specimen source of these strains were urine,lower respiratory tract specimens,and wound secretions.Proteus,Morganella,and Providencia isolates showed lower resistance rates to amikacin,meropenem,cefoxitin,cefepime,cefoperazone-sulbactam,and piperacillin-tazobactam.For most of the antibiotics tested,less than 10％of the Proteus and Morganella strains were resistant,while less than 20％of the Providencia strains were resistant.The prevalence of carbapenem-resistant Enterobacterales(CRE)was 1.4％in Proteus isolates,1.9％in Morganella isolates,and 15.6％in Providencia isolates.Conclusions The overall number of clinical isolates of Proteus,Morganella and Providencia increased significantly in the 7-year period from 2015 to 2021.The prevalence of CRE strains also increased.More attention should be paid to antimicrobial resistance surveillance and rational antibiotic use so as to prevent the emergence and increase of antimicrobial resistance.

Objective To understand the changing distribution and antimicrobial resistance profiles of Klebsiella strains in 52 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Antimicrobial susceptibility testing was carried out according to the unified CHINET protocol.The susceptibility results were interpreted according to the breakpoints in the Clinical & Laboratory Standards Institute(CLSI)M100 document.Results A total of 241,549 nonduplicate Klebsiella strains were isolated from 2015 to 2021,including Klebsiella pneumoniae(88.0％),Klebsiella aerogenes(5.8％),Klebsiella oxytoca(5.7％),and other Klebsiella species(0.6％).Klebsiella strains were mainly isolated from respiratory tract(48.49±5.32)％.Internal medicine(22.79±3.28)％,surgery(17.98±3.10)％,and ICU(14.03±1.39)％were the top 3 departments where Klebsiella strains were most frequently isolated.K.pneumoniae isolates showed higher resistance rate to most antimicrobial agents compared to other Klebsiella species.Klebsiella isolates maintained low resistance rates to tigecycline and polymyxin B.ESBLs-producing K.pneumoniae and K.oxytoca strains showed higher resistance rates to all the antimicrobial agents tested compared to the corresponding ESBLs-nonproducing strains.The K.pneumoniae and carbapenem-resistant K.pneumoniae(CRKP)strains isolated from ICU patients demonstrated higher resistance rates to majority of the antimicrobial agents tested than the strains isolated from non-ICU patients.The CRKP strains isolated from adult patients had higher resistance rates to most of the antimicrobial agents tested than the corresponding CRKP strains isolated from paediatric patients.Conclusions The prevalence of carbapenem-resistant strains in Klebsiella isolates increased greatly from 2015 to 2021.However,the Klebsiella isolates remained highly susceptible to tigecycline and polymyxin B.Antimicrobial resistance surveillance should still be strengthened for Klebsiella strains.

Objective To investigate the changing distribution and antibiotic resistance profiles of clinical isolates of Staphylococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Staphylococcus according to the unified protocol of CHINET(China Antimicrobial Surveillance Network)using disk diffusion method and commercial automated systems.The CHINET antimicrobial resistance surveillance data from 2015 to 2021 were interpreted according to the 2021 CLSI breakpoints and analyzed using WHONET 5.6.Results During the period from 2015 to 2021,a total of 204,771 nonduplicate strains of Staphylococcus were isolated,including 136,731(66.8％)strains of Staphylococcus aureus and 68,040(33.2％)strains of coagulase-negative Staphylococcus(CNS).The proportions of S.aureus isolates and CNS isolates did not show significant change.S.aureus strains were mainly isolated from respiratory specimens(38.9±5.1)％,wound,pus and secretions(33.6±4.2)％,and blood(11.9±1.5)％.The CNS strains were predominantly isolated from blood(73.6±4.2)％,cerebrospinal fluid(12.1±2.5)％,and pleural effusion and ascites(8.4±2.1)％.S.aureus strains were mainly isolated from the patients in ICU(17.0±7.3)％,outpatient and emergency(11.6±1.7)％,and department of surgery(11.2±0.9)％,whereas CNS strains were primarily isolated from the patients in ICU(32.2±9.7)％,outpatient and emergency(12.8±4.7)％,and department of internal medicine(11.2±1.9)％.The prevalence of methicillin-resistant strains was 32.9％in S.aureus(MRSA)and 74.1％in CNS(MRCNS).Over the 7-year period,the prevalence of MRSA decreased from 42.1％to 29.2％,and the prevalence of MRCNS decreased from 82.1％to 68.2％.MRSA showed higher resistance rates to all the antimicrobial agents tested except trimethoprim-sulfamethoxazole than methicillin-susceptible S.aureus(MSSA).Over the 7-year period,MRSA strains showed decreasing resistance rates to gentamicin,rifampicin,and levofloxacin,MRCNS showed decreasing resistance rates to gentamicin,erythromycin,rifampicin,and trimethoprim-sulfamethoxazole,but increasing resistance rate to levofloxacin.No vancomycin-resistant strains were detected.The prevalence of linezolid-resistant MRCNS increased from 0.2％to 2.3％over the 7-year period.Conclusions Staphylococcus remains the major pathogen among gram-positive bacteria.MRSA and MRCNS were still the principal antibiotic-resistant gram-positive bacteria.No S.aureus isolates were found resistant to vancomycin or linezolid,but linezolid-resistant strains have been detected in MRCNS isolates,which is an issue of concern.

Objective:To study the mechanistic role of myeloid-specific Notch1 knockout inhibiting STING signaling to regulate hepatocyte lipophagy.Methods:A mouse model of nonalcoholic steatohepatitis (NASH) was established using a high-fat diet (HFD) and mouse bone marrow-derived macrophages (BMMs). Primary hepatocytes were isolated to construct a co-culture system. Twelve Notch1 FL/FL mice were randomly divided into two groups: the Notch1 FL/FL + normal diet (NCD) and the Notch1 FL/FL + HFD group. Further, 12 Notch1 M-KO mice were randomly divided into two groups: Notch1 M-KO + NCD, and Notch1 M-KO + HFD group.Serum alanine aminotransferase (sALT), total cholesterol (TC) and triglyceride (TG) were collected from mice serum samples. Liver tissue samples were collected for H&E staining, immunofluorescence (IF), Western blot and qRT-PCR. Tumor necrosis factor (TNF)-α was detected in the supernatant by enzyme-linked immunosorbent assay (ELISA). The comparison of inter group data was conducted using a t-test. Results:The mouse NASH model, mouse BMMs co-culture system, and primary hepatocytes were successfully constructed. Compared with the Notch1 FL/FL + HFD group, the Notch1 M-KO + HFD group showed a significant increase in serum ALT [(250.02 ± 58.21) U/L vs (370.70 ± 54.57) U/L, t = 3.705, P = 0.004], TG [(29.90 ± 3.54) mg/g vs (43.83 ± 8.56) mg/g, t = 3.685, P = 0.004], and TC [(33.70 ± 8.43) mg/g vs (90.53 ± 12.53) mg/g, t = 9.917, P < 0.001]. HE staining of liver tissue showed remarkable balloon-like alterations in liver cells, while IF staining demonstrated increased macrophage infiltration ( t = 7.346, P < 0.001). Compared with the hepatocyte group co-cultured with Notch1 FL/FL BMMs, the BODIPY probe showed a significant increase in lipid droplet (LDs) deposition in liver cells in the Notch1 M-KO group ( t = 3.835, P < 0.001). The co-localization of lysosomal associated membrane protein 1 (LAMP1), LDs ( t = 7.103, P < 0.001), microtubule-associated protein light chain 3 (LC3) -II/LC3-I ( t = 5.0, P = 0.007), and autophagy associated gene 12 (Atg12) ( t = 28.36, P < 0.001) had decreased expression, while P-62 had increased expression ( t = 3.253, P = 0.03), indicating a decrease in autophagic flow. Additionally, LC3 and LDs colocalization decreased ( t = 5.24, P = 0.0003), indicating reduced lipophagy. Compared with the Notch1 FL/FL group, the Notch1 M-KO BMMS mouse group showed an increase in the expression of p-STING ( t = 5.318, P = 0.006), p-TANK1 binding kinase 1 (TKB1) ( t = 6.467, P = 0.002), p-interferon regulatory factor 3 (IRF3) ( t = 14.61, P < 0.001), and p-P65 ( t = 12.7, P = 0.002) protein, accompanied by mRNA expression of the inflammatory mediators interferon (IFN)-β ( t = 7.978, P < 0.001), TNFα ( t = 8.496, P = 0.001), interleukin-1 β (IL-1 β) ( t = 4.7, P < 0.001), and CXCL-10 ( t = 4.428, P = 0.001). The STING gene was knocked out in the BMMs Notch1 M-KO mice using CRISPR/Cas9. Compared with the CRISPR-Control group, the expression of P-TKB1 ( t = 2.909, P = 0.044), p-IRF3 ( t = 10.96, P < 0.001), p-IRF3 ( t = 10.96, P < 0.001), and p-P65 ( t = 7.091, P = 0.002) proteins was lower in the STING-KO BMMs group. The release of TNF-α in the supernatant was decreased (732.3 ± 129.35 pg/ml vs. 398.17 ± 47.15 pg/ml, t = 4.204, P = 0.014). However, in hepatocytes co-cultured with STING-KO BMMs, LC3-II/LC3-I ( t = 7.546, P = 0.001) increased, p-62 ( t = 10.96, P < 0.001) expression decreased, autophagic flow increased, and the colocalization of LC3 and LDs increased, lipophagy increased, and LDs deposition decreased. Conclusion:Myeloid-specific Notch1 knockout can activate macrophages STING signaling, increase the expression of inflammatory mediator genes, inhibit the occurrence of autophagy flow and lipophagy in hepatocyte cells, and aggravate LDs deposition and NASH progression.

Objective:To study the predictive value of the amplitude-integrated electroencephalography (aEEG) within 6 hours and 3 days after birth and magnetic resonance imaging(MRI) on the adverse neurobehavioral development of asphyxiated preterm infants at the correction age of 6 months.Methods:From December 2017 to June 2019, 50 asphyxiated preterm infants who were delivered at the obstetrical department transferred to the division of neonatology in the Third Affiliated Hospital of Anhui Medical University were monitored by aEEG within 6 hours after birth, then once a day for at least 4 h. MRI was administered at 40 weeks of corrected age, neuromotor developmental function of the infants was assessed by the Geisel developmental diagnostic scale at 6 months of corrected age, then the infants were divided into good prognosis group and poor prognosis group according to the assessment results. SPSS 19.0 software was used for statistical analysis.The software of SPSS 19.0 was used to analyze the data.Independent sample t-test and χ 2 test were used to analyze the difference between the two groups.The relationship between aEEG grading and MRI, and their predictive value for adverse neurobehavioral development were analyzed at 6 months of corrected age. Results:The degree of white matter damage( H=24.896) and intracranical hemorrhage( H=29.245) of premature infants with different aEEG clinical grades were different (both P<0.01) on MRI. The sensitivity of aEEG within 6 hours and 3 days after birth on predicting poor prognosis was 96.2% and 97.8%, the specificity was 56.2% and 62.5%, the negative predictive value was 98.2% and 99.0%, the positive predictive value was 37.8% and 52.3%, the correct index was 52.4% and 60.3%, respectively. The aEEG was combined with MRI, the sensitivity (90.0%, 97.0%), specificity (89.0%, 99.0%), negative predictive value (99.2%, 99.5%), positive predictive value (80.6%, 88.5%), and correct index (79%, 96%) were all improved. Conclusion:The combination of aEEG grading and MRI can improve the prognostic value on neurodevelopmental prognosis, and provide a better evaluation basis for clinical follow-up and intervention of asphyxiated premature infants with brain injury.

Objective To investigate the change and significance of follicular helper T cells (Tfh) percentage in the peripheral blood of the patients with rheumatoid arthritis (RA).Methods The RA patients treated in this hospital from September to November 2016 were selected and divided into the RA active group and RA stable group,35 cases in each group.Contemporaneous 35 individuals undergoing physical examination were selected as the healthy control group.The percentage of peripheral blood CD4+ CXCR5+ ICOS+ Tfh cells was detected by flow cytometry.The correlations between the percentage of peripheral blood Tfh cells in RA patients with the RA disease activity score 28 (DAS28),anti-CCP antibody and rheumatoid factor(RF) levels were analyzed.Results The percentage of peripheral blood Tfh cells in the RA active group was (0.84±0.16) ％,which was significantly higher than (0.64±0.15)％ in the RA stable group and (0.56±0.14)％ in the healthy control group,the difference was statistically significant (P＜0.01);moreover the percentage of peripheral blood Tfh cells in the RA stable group was also higher than that in the healthy control group (P＜0.05).The percentage of peripheral blood Tfh cells in RA patients had significantly positive correlation with DAS28 score and anti-CCP antibody level (r=0.355,0.324;P＜0.01),and had no correlation with the RF level (r=0.205,P＞0.05).Conclusion The percentage increase of peripheral blood Tfh cells in the patients with RA might be related with the pathogenesis and development of RA.

Objective To investigate the effects of HepG2 and HepG2.2.15 cells steatosis on the mRNA and protein expressions of suppressors of cytokine signaling-3(SOCS-3) and sterol regulatory element binding proteins (SREBP-1c).Methods The cell model of chronic hepatitis B (CHB) combined with nonalcoholic fatty liver disease (NAFLD) was successfully constructed using an oleic acid-induced HepG2 and HepG2.2.15 cells steatosis.Cells were divided into HepG2 cell control group (HepG2 cell control group), HepG2.2.15 cell control group (HepG2.2.15 cell control group), HepG2 cell steatosis group (HepG2 cell steatosis group) and HepG2.2.15 cell steatosis group (HepG2.2.15 cell steatosis group).The expression levels of SOCS-3 and SREBP-1c mRNA were detected by real-time quantitative polymerase chain reaction (PCR).Changes in protein expressions of SOCS-3 and SREBP-1c were measured by western blot.Results SOCS-3 mRNA expression level in HepG2.2.15 cell control group was significantly lower than that in HepG2 cell control group (P<0.01).The level in HepG2 cell steatosis group was also significantly lower than that in HepG2 cell control group (P<0.01).However, the level of SOCS-3 mRNA in HepG2.2.15 cell steatosis group was lower than HepG2.2.15 cell control group with no statistical significance (P=0.173).There was interaction between cells and steatosis (F=25.547, P<0.01).The expression of SREBP-1c mRNA in HepG2.2.15 cell control group was significantly lower than that in HepG2 cell control group (P<0.01), and was significantly higher in HepG2.2.15 cell steatosis group than that in HepG2.2.15 cell control group (P<0.01).There was no significant difference between HepG2 cell steatosis group and HepG2 cell control group (P=1.000).There was interaction between cells and steatosis (F=5.04, P<0.05).Western blot analysis showed that protein levels of SOCS-3 and SREBP-1c in steatosis cells at 48 h and 72 h were significantly higher than those in non-alcoholic steatosis cells.Conclusions Protein expressions of SOCS-3 and SREBP-1c are up-regulated in both steatosis groups.Factorial analysis shows that there is interaction between cells and steatosis.HBV gene could inhibit SOCS-3 mRNA expression and promote the expression of SREBP-1c mRNA in steatosis cells.