Objective To gain insights into the biological characteristics of different populations of Culex tritaeniorhynchus within and around the Yellow Sea wetland from the perspective of the occurrence of resistance, we investigated the levels of resistance to deltamethrin and kdr gene mutation in the wetland and its peripheral areas. Methods Specimens were collected from Cx. tritaeniorhynchus populations at two monitoring sites in the Rare Bird National Nature Reserve and Tiaozi Ni Wetland Scenic Area, and also from two populations in Yancheng City and the Liuhe District of Nanjing, and the resistance of these mosquitoes to deltamethrin was determined using the CDC biotest bottle method. For each concentration of deltamethrin assessed, a random subset of exposed specimens was selected for amplification of the kdr gene fragment, followed by Sanger sequencing to identify and analyze resistance-associated mutations. Results The LC50 levels of deltamethrin among mosquitoes from the four populations in Luhe, Yancheng, the Rare Bird National Nature Reserve and the Tiaozi Ni Wetland Scenic Area were 2.048 5, 7.798 2, 3.473 3, and 17.695 5 mg/mL, respectively, with corresponding concentrations of deltamethrin ranging from 0.005 to 5.000,0.050 to 50.000,0.050 to 25.000 and 0.050 to 50.000 mg/mL, respectively. Furthermore, the ranges of the KT50 values were 11.76-107.43, 67.05-216.30,29.77-107.43 and 28.40-329.51 min; the 1-h knockdown rates were 34.58%-99.15%, 9.52%-43.80%, 55.09%-73.01%, and 10.09%-68.07%; and the 24-h mortality rates were 12.15%-67.52%,9.52%-79.56%,13.17%-82.21%, and 11.01%-78.99%, respectively. With respect to kdr gene mutation, we assayed a total of 63,70,59, and 57 mosquitoes for the four populations, for which we detected L1014F mutation frequencies of 14.29%, 35.00%, 20.34%, and 31.58%, respectively, with a majority of these mutations being heterozygous for resistance. In addition, five adult mosquitoes were identified has having synonymous mutations at site 1011[i. e. , AAT(asparagine)mutation to AAC(asparagine)]. Conclusions Our findings revealed the clear resistance of Cx. tritaeniorhynchus to deltamethrin in the Yancheng region of the Yellow Sea wetland, and the resistance phenotype and kdr frequency of Cx. tritaeniorhynchus in the wetland environment were comparable to those of Cx. tritaeniorhynchus in the wetland environment, thereby indicating that the resistance of different populations of Cx. tritaeniorhynchus was homogeneous under the pressure of different insecticide selection within and around the wetland. However, the underlying mechanisms need to be further studied.

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 summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

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 understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

Objective:To analyze the differences in clinicopathological features between non-elderly and elderly patients with melanoma, and to identify risk factors for prognosis in elderly patients with melanoma.Methods:A retrospective analysis was conducted on clinical and pathological data collected from non-elderly (aged < 60 years) and elderly (aged ≥ 60 years) patients with melanoma, who were confirmedly diagnosed according to clinical manifestations and histopathological findings at the People's Hospital of Xinjiang Uygur Autonomous Region from January 2008 to December 2023. The differences in clinical and pathological characteristics between the two groups were analyzed using the chi-square test and Wilcoxon rank-sum test. Survival curves were estimated using the Kaplan-Meier method and log-rank test. The relationship between clinicopathological variables and overall survival was analyzed using a Cox regression model.Results:A total of 233 patients with cutaneous melanoma were included, with the age being 60.3 ± 14.7 years, and the number of patients was highest in the age group of 60 - 69 years. There were 102 cases (43.8%) in the < 60 years old group and 131 cases (56.2%) in the ≥ 60 years old group. Compared with the < 60 years old group, the ≥ 60 years old group showed a significant increase in the proportion of patients with active tumor-infiltrating lymphocytes ( P = 0.040), proportion of those with Ki-67 index ≥ 30% ( P = 0.010), and Charlson comorbidity index ( P = 0.002), but a significant decrease in the proportion of patients with BRAF/KIT/NRAS mutations ( P = 0.003), proportion of those receiving surgical treatment ( P = 0.034), and proportion of those receiving adjuvant therapy ( P = 0.042). There was a significant difference in the overall survival between the two groups (log-rank test, χ2 = 6.10, P = 0.014). The gender, metastasis status, presence or absence of ulceration, distant metastasis status, American Joint Committee on Cancer staging, Charlson comorbidity index, and Breslow thickness were important prognostic indicators affecting the overall survival in the elderly patients with melanoma. Multivariate Cox regression analysis showed that males ( P = 0.015, HR = 4.622, 95% CI: 1.352 - 15.798), presence of distant metastasis ( P = 0.013, HR = 9.844, 95% CI: 4.621 - 59.763), and Charlson comorbidity index ≥ 3 ( P = 0.038, HR = 3.149, 95% CI: 1.067 - 9.294) were independent risk factors affecting the overall survival in the elderly patients with melanoma. Conclusions:Compared with the non-elderly patients with melanoma, a higher Ki-67 index, a higher Charlson comorbidity index, less surgical treatment, and less adjuvant therapy were more common in the elderly patients with melanoma. Males, the presence of distant metastasis, and Charlson comorbidity index ≥ 3 appeared to be independent risk factors affecting the overall survival in the elderly patients with melanoma.

Objective:To investigate the influences of long non-coding RNA metastasis-associated lung adenocarcinoma tran-script 1(lncRNA MALAT1)/miR-876-5p/forkhead box protein M1(FOXM1)axis on TNF-α-induced proliferation,apoptosis and in-flammatory response of HaCaT cells.Methods:HaCaT cells were grouped into Ct group,Model group,si-NC group,si-MALAT1 group,mimic NC group,miR-876-5p mimic group,si-MALAT1+inhibitor NC group,and si-MALAT1+miR-876-5p inhibitor group.Except for the Ct group,cells in other groups were treated with 25 μg/L TNF-α to induce the in vitro cell model of psoriasis,and after 24 hours of TNF-α induction,the corresponding transfectants were transfected for 48 hours for subsequent experiments.qRT-PCR was applied to detect the expression of MALAT1 and miR-876-5p in cells;CCK-8 method and EdU staining were applied to detect cell pro-liferation;flow cytometry was applied to detect apoptosis;ELISA method was applied to detect the levels of IL-6,TNF-α,and IL-1β in cell supernatant;Western blot was applied to detect the protein expressions of FOXM1,proliferating cell nuclear antigen(PCNA),Bcl-2-associated X protein(Bax)and B-lymphocytoma-2(Bcl-2);dual-luciferase reporter gene assay was applied to verify the rela-tionship between MALAT1 and miR-876-5p,miR-876-5p and FOXM1;and RNA pull down experiments were applied to verify the re-lationship between MALAT1 and miR-876-5p.Results:Compared with the control group,the expressions of MALAT1 and FOXM1 protein expression in the experimental group were increased,and the expression of miR-876-5p was decreased(P<0.05);compared with Ct group,the expressions of MALAT1 and FOXM1 protein expression in HaCaT cells,A450 value,EdU positive rate,the levels of IL-6,TNF-α,IL-1β,and the protein expressions of PCNA and Bcl-2 in cell supernatant in Model group increased,the expression of miR-876-5p,apoptosis rate and the protein expression of Bax were decreased(P<0.05);silencing MALAT1 or overexpressing miR-876-5p could inhibit the proliferation and inflammatory response of HaCaT cells induced by TNF-α,and promote cell apoptosis;miR-876-5p inhibitor attenuated the inhibitory effects of silencing MALAT1 on TNF-α-induced HaCaT cell proliferation and inflammatory response,and the promotion on cell apoptosis;MALAT1 targeted and regulated the miR-876-5p/FOXM1 axis.Conclusion:Silencing MALAT1 may inhibit the expression of FOXM1 by up-regulating miR-876-5p,thereby inhibiting the proliferation and inflammatory re-sponse of HaCaT cells induced by TNF-α,and promoting cell apoptosis.

Objective To explore the influencing factors of early neurological deterioration(END)in patients with acute anterior circulation large-vessel occlusive mild stroke who were treated with medications alone within 72 h after onset.Methods Retrospective consecutive data were collected of patients with acute large-vessel occlusive mild stroke who presented to the Advanced Stroke Center of Linyi People's Hospital within 24 h of onset from January 2021 to December 2022.END was defined as an increase of ≥ 4 points in the National Institutes of Health stroke scale(N1HSS)score within 72 h after onset compared to the admission score.Patients were divided into the neurological deterioration group and the stable condition group(NIHSS score did not increase or increased by 1-3 points within 72 h after onset compared to the admission score).Baseline and clinical data of all patients were collected,including sex,age,cerebrovascular disease risk factors(hypertension,diabetes mellitus,hyperlipidemia,coronary heart disease,atrial fibrillation,smoking,alcohol consumption,stroke history),NIHSS score at admission,time from onset to admission,systolic blood pressure at admission,diastolic blood pressure at admission,laboratory test indicators at admission(blood glucose,glycosylated hemoglobin,homocysteine,total cholesterol,triglyceride,low-density lipoprotein cholesterol,high-density lipoprotein cholesterol,neutrophils,lymphocytes and neutrophil-to-lymphocyte ratio),responsible occlusion artery(internal carotid artery,middle cerebral artery,anterior cerebral artery),affected cerebral hemisphere,collateral circulation score,and medications used within 72 h after admission(intravenous thrombolysis+dual antiplatelet therapy,tirofiban+dual antiplatelet therapy,argatroban+dual antiplatelet therapy,argatroban alone,dual antiplatelet therapy alone).Variables with statistically significant differences in univariate analysis were included in multivariate Logistic regression analysis to explore the independent influencing factors for END in patients with acute anterior circulation large-vessel occlusive mild stroke treated with medications alone.Results A total of 208 patients with acute anterior circulation large-vessel occlusive mild stroke were included,with 143 males and 65 females,aged 38-85 years,with an average age of(64±9)years.Among them,86 patients were in the neurological deterioration group and 122 in the stable condition group.(1)There were statistically significant differences between the neurological deterioration group and the stable condition group in terms of history of diabetes mellitus(39.5％[34/86]vs.17.2％[21/122]),smoking history(43.0％[37/86]vs.29.5％[36/122]),left cerebral hemisphere lesion(57.0％[49/86]vs.41.0％[50/122]),collateral circulation score(4[3,5]vs.5[4,5]),time from onset to admission(7.0[3.0,17.0]hvs.4.3[2.0,11.0]h),blood glucose at admission(7.4[5.8,10.0]mmol/L vs.6.7[5.8,7.7]mmol/L),neutrophil-to-lymphocyte ratio(3.8[2.4,5.1]vs.3.0[2.1,4.3]),dual antiplatelet therapy alone(19.8％[17/86]vs.6.6％[8/122]),and argatroban+dual antiplatelet therapy(8.1％[7/86]vs.29.5％[36/122];all P＜0.05).There were no statistically significant differences in the results of the remaining univariate analyses(all P＞0.05).(2)Multivariate Logistic regression analysis showed that diabetes mellitus(OR,2.674,95％CI 1.121-6.377,P=0.027)and left cerebral hemisphere vessel occlusion(OR,2.030,95％CI I.083-3.806,P=0.027)were independent risk factors for END in acute anterior circulation large-vessel occlusive mild stroke.Argatroban+dual antiplatelet therapy(OR,0.267,95％CI 0.116-0.613,P=0.002)and high collateral circulation score(OR,0.551,95％CI 0.368-0.824,P=0.004)were independent protective factors for END in acute anterior circulation large-vessel occlusive mild stroke.Conclusions Acute anterior circulation large-vessel occlusive mild stroke patients with diabetes mellitus or left cerebral hemisphere lesions are prone to END.The combination of argatroban and dual antiplatelet therapy and good collateral circulation can reduce the risk of END.