Aim To explore whether platelet-derived growth factor C(PDGFC)derived from cancer-associat-ed fibroblasts(CAFs)can promote resistance of breast cancer cells to doxorubicin(DOX)and the underlying mechanisms.Methods CAFs and normal fibroblasts(NFs)were extracted from freshly resected breast cancer tissue and adjacent normal breast tissue respec-tively.Conditioned medium(CM)from CAFs and NFs was collected and co-cultured with breast cancer cells.Cell proliferation and toxicity were assessed using a Cell Counting Kit-8(CCK-8).The expression of PDG-FC in CAFs,NFs and corresponding CM was detected by Western blot and ELISA respectively.The influence of CAFs-CM on intracellular doxorubicin content in breast cancer cells was observed by fluorescence mi-croscopy.The impact of CAFs-CM on apoptosis-related proteins BAX and BCL2 was predicted and valifated u-sing the Starbase database and Western blot.The changes in ROS levels,mitochondrial membrane po-tential,and mitochondrial membrane proteins TOM20 and COX Ⅳ in breast cancer cells were measured using DCFH-DA fluorescence staining,JC-1 assay,and Western blot.Results CAFs-CM decreased the intra-cellular doxorubicin content and inhibited the sensitivi-ty of breast cancer cells to doxorubicin.Additionally,the expression of apoptosis protein BAX decreased while the anti-apoptotic protein BCL2 increased in breast cancer cells cultured with CAFs-CM.Further-more,CAFs-CM led to decreased ROS levels and in-creased mitochondrial membrane potential in breast cancer cells accompanied with elevated expression of mitochondrial membrane proteins TOM20 and COX Ⅳ.Further study found that PDGEF was highly expressed in CAFs and CAFs-CM,recombinant human PDGFC produced resistance of breast cancer cells to DOX simi-lar to CAFs-CM,and the specific inhibitors of PDGFRα significantly inhibited CAFs-CM.Further mechanistic studies revealed that PDGFC in CAFs-CM induced chemoresistance by activating PI3K-mTOR signaling pathway.Conclusion PDGFC secreted by CAFs promotes doxorubicin resistance in breast cancer cells through PI3K-mTOR signaling pathway,which provides a new perspective for the development of anti-cancer drugs targeting CAFs.

Aim To investigate the changes in the proliferation and apoptosis of Siha cells after knocking down Rho GTPase-activating protein 30(ARHGAP30).Methods After designing specific shARHGAP30 primers and connecting them to the pLKO.1 vector,we transformed them into Escherichia coli competent cells,then co-transfecting them with lentiviral helper plasmids into HEK-293T cells.We collected and filtered cell supernatant to obtain the vi-rus to infect Siha cells.RT-qPCR and Western blot were used to detect knockdown efficiency,as well as changes in the expression of Bax and Bcl-2 after trans-fection.The CCK-8 method was employed to measure the proliferation level of cells after knockdown.Results After successful construction of a lentiviral plasmid with knockdown of the ARHGAP30 gene and establish-ment of stably transfected Siha cells,ARHGAP30 tran-scription and translation(P＜0.01)in Siha cells de-creased,Bax/Bcl-2 significantly decreased(P＜0.01),indicating decreased apoptosis and increased cell proliferation(P＜0.01).Conclusions This study suggests the involvement of ARHGAP30 in the proliferation and apoptosis of Siha cells,and regulating the ARHGAP30 gene may interfere with the occurrence and development of cervical cancer.

Aim To observe the behavioral effects of exogenous allopregnanolone(ALLO)and its inhibitor finasteride on the receptive period(R)and non-recep-tive period(NR)of PMDD liver-qi inversion model rats and the expression of GABAARα4,GABAARδ mR-NA and protein effects to explore its pathogenesis.Methods The PMDD liver-qi reverse syndrome rat model was prepared.The rats were divided into the normal group R and NR(control-R,control-NR),model group R and NR(Model-R,Model-NR),nor-mal group R+ALLO and NR+ALLO(Control+A-R,Control+A-NR),and model group R+ALLO and NR+ALLO(Model+A-R,Model+A-NR),model group R+finasteride and NR+finasteride(Model+F-R,Model+F-NR).The elevated cross labyrinth ex-periment and social interaction experiment were used to detect the behaviors of rats;fluorescence quantitative PCR and immunofluorescence were used to detect the expression of GABAARα4 and 8 mRNA and protein in rat amygdala and hippocampus.Results In the be-havioral evaluation,in the NR period,in the elevated cross maze test and in the social interaction test,the rats in the model group had anxiety behavior and de-creased social communication ability(P＜0.05),while the rats in the Model+A group could effectively relieve anxiety symptoms and improve their social com-munication ability(P＜0.05),and the rats in the Model+F group had increased anxiety behavior and social disorder(P＜0.05).In fluorescence quantita-tive PCR and immunofluorescence experiments,the ex-pression of GABAARα4 subunit in the model group was up-regulated in the hippocampus(P＜0.01),and the expression of δ subunit was down-regulated(P＜0.01);the expression of GABAARα4 subunit in the a-mygdala and hippocampus of the Model+A group de-creased(P＜0.01),and the expression of δ subunit increased in the hippocampus(P＜0.01).Conclu-sions The abnormal expression of GABAARα4 and 8 subunits mediated by ALLO improves the anxiety symptoms and social interaction ability of PMDD,which is the pathogenesis of PMDD liver-qi reverse syndrome,and provides basis and support for subse-quent exploration of the pathogenesis of PMDD liver-qi reverse syndrome.

Aim To study the mechanism of action of licorice in alleviating cisplatin liver injury.Methods Forty-eight SD rats were randomly divided into a blank group,a model group,a positive control group and lico-rice administration groups(450,900 and 1 800 mg·kg-1).After 5 days of prophylactic administration,8 mg·kg-1 of cisplatin was injected intraperitoneally in-to the model,positive control,and licorice administra-tion groups to establish an acute liver injury model.LC-MS/MS untargeted metabolomics was used to ana-lyze the differential metabolites and metabolic pathways of licorice to alleviate cisplatin acute liver injury.Re-sults PLS-DA score plots showed significant separa-tion of metabolomics samples.The analysis yielded 119 differential metabolites associated with cisplatin liver injury,of which 31 differential metabolites were signifi-cantly regressed after licorice intervention and were mainly involved in D-arginine and D-ornithine metabo-lism;parathyroid hormone synthesis,secretion,and ac-tion;tyrosine metabolism;biosynthesis of phenylala-nine,tyrosine,and tryptophan;β-alanine metabolism;and amino acid and nucleotide sugar metabolism.Con-clusions Metabolomics analysis indicates that licorice can alter the metabolic profile of cisplatin-induced he-patic injury rats,and its mechanism of action may be related to its improvement of the levels of differential metabolites and its involvement in the regulation of a-mino acid metabolism and other related pathways.

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.