OBJECTIVE: To explore mechanisms of acid-sensing ion channel 1 (ASIC1) mediated lumbar nucleus pulposus cell apoptosis through extracellular-signalregulated protein kinase 5 (ERK5) signaling pathway and mitochondrial dysfunction pathway. METHODS: Totally 34 patients with degenerative lumbar disc herniation (LDH) admitted from January 2020 to December 2022 were collected as research objects, including 21 males and 13 females;aged from 29 to 52 years old with an average of (37.43±4.75) years old;22 patients with grade Ⅱ and 12 patients with grade Ⅳ, according to Pfirrmann grading criteria;15 patients with L_4,5 and 19 patients with L₅S₁. The expression of ASIC1 in nucleus pulposus of LDH patients was measured by immunohistochemical staining. Nucleus pulposus cells were cultured by primary culture method, identified by toluidine blue staining and immunohistochemical staining, and the expression of ASIC1 protein was located by immunofluorescence staining. According to the addition of siRNA-ASIC1, ASIC1 overexpression plasmid, and ERK5 inhibitors, the nucleus pulpocyte was divided into three groups, named as SIRNA-silenced group, overexpression group, and inhibitor group, with 3 patients in each group. Cells of each group were collected at 72 h after intervention, expression of ASIC1, ERK5, BCL-xL/BCL-2-associated Death promoter (Bad), B-cell lymphoma-2 associated X (Bax) and B-cell lymphoblast-2 gene (Bcl-2) were detected by reverse transcription-polymerase chain reaction (RT-PCR);intracellular calcium ion levels were detected by calcium ion kit, mitochondrial membrane potential was detected by JC-1 kit, and apoptosis was observed by AV-PI kit. RESULTS: In LDH patients with grade Ⅳ, nucleus pulposus tissue removed during operation revealed poor elasticity, white color and poor ductility, and immunohistochemical results showed increased ASIC1 expression. There was no significant difference in mRNA relative expression of ASIC1 between siRNA silencing group (0.31±0.03) and inhibitor group (0.39±0.05) (P>0.05). The mRNA relative expression level of ERK5 in siRNA silencing group(0.32±0.05) was significantly higher than that in inhibitor group (0.15±0.04)(P<0.05), which suggested ERK5 was the downstream molecule of ASIC1. The mRNA relative expression levels of apoptosis promoting factor Bad and Bax in siRNA silencing group and inhibitor group were lower than those in overexpression group(P<0.05), the relative expression level of anti-apoptosis factor Bcl-2 mRNA was significantly increased (P<0.05). The calcium content in overexpression group was higher than that in siRNA silencing and inhibitor groups (P<0.05), the normal proportion of mitochondrial membrane potential in overexpression group was lower than that in siRNA silencing and inhibitor group (P<0.05), and the apoptosis rate in overexpression group was higher than that in siRNA silencing and inhibitor group (P<0.05). CONCLUSION After the activation of ASIC1 channel protein, calcium ions could enter the cells and act as a second messenger molecule to regulate apoptosis of nucleus pulposus cells by ERK5 signaling pathway and mitochondrial disorder pathway.
Humans ; Acid Sensing Ion Channels/physiology* ; Male ; Female ; Apoptosis ; Middle Aged ; Adult ; Signal Transduction ; Mitogen-Activated Protein Kinase 7/physiology* ; Mitochondrial Diseases/genetics* ; Nucleus Pulposus/metabolism* ; Intervertebral Disc Degeneration/metabolism* ; Mitochondria/metabolism* ; Intervertebral Disc Displacement/genetics*

Objective To construct a risk prediction model for liver cancer in patients with chronic hepatitis C based on seven different machine learning algorithms and select the optimal model. Methods A total of 236 patients with chronic hepatitis C were selected as the research subjects. Patients were divided into a case group and a control group according to whether liver cancer occurs. Prediction models were constructed based on seven machine learning algorithms including classification and regression tree, random forest, gradient boosting decision tree, extreme gradient boosting (XGBoost), logistic regression, K-near neighbor, and support vector machine. The Shapley additive explanations (SHAP) algorithm was used to interpret the best prediction model. Results Among the seven models, the XGBoost model had the best comprehensive prediction performance (accuracy of 0.933, sensitivity of 0.775, specificity of 0.960, area under the ROC curve of 0.956, F1 score of 0.764). The SHAP algorithm suggested that AFP, age, AST, diabetes, BMI, PLT, ALT, liver cysts, FIB-4, and gender contributed to the model decision and are the risk factors for liver cancer in patients with chronic hepatitis C. Conclusion This study develops an interpretable machine learning model based on the XGBoost algorithm, which has a good reference value for individualized monitoring of liver cancer in patients with chronic hepatitis C.

Objective:To investigate the expression and role of DEAD-box RNA helicases 5(DDX5 helicases)in head and neck squamous carcinoma(HNSCC).Methods:Tissue microarray microarray was used to assess relevant mRNA expression profile data,and R software was used to screen differential mRNAs(DEGs).The expression level of DDX5 was predicted using GEPIA 2,TCGA databases,and detected by immunohistochemistry,western blot and RT-qPCR in the HNSCC tissue and cell lines.Based on high-throughput sequencing data of DECs,differentially expressed miRNAs(DEMIs)relevant DDX5 competitive endogenous RNA network(ceRNA)was constructed.The software cytoscape was used to visualize the ceRNA network map and further screen the regulatory ax-is.Results:The results of microarray screening revealed that DDX5 expression in HNSCC was upregulated.Immunohistochemistry ver-ified that DDX5 was stronger expressed in the nuclei of squamous carcinoma cells.qPCR results suggested that significant expression of DDX5 mRNA at the tissue and cellular levels(P＜0.05).Western blot results showed high expression of DDX5 protein in the tissues.The ceRNA network was constructed,from which the relevant HNSCC axis circRNA-039626-miR-222-5p-DDX5 was identified.Con-clusion:DDX5 is highly expressed in HNSCC,and the circRNA-039626-miR-222-5p-DDX5 axis may be a potential regulatory axis for the development of HNSCC.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

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.