Objective To investigate the identification of octreotide(OCT)modified chitosan(CS)miR-155 molecular beacon nanoparticles(CS-miR-155-MB-OCT)and imaging of lung cancer cells for the early screening of lung cancer.Methods A nude mouse model of lung transplantation tumor was established by injecting A549 lung cancer cells into tail veins to establish lung xenograft models.Cre adenovirus was injected through nasal cavity,and mice were killed at 4,6,8 and 12 weeks after adenovirus injection to establish lung cancer models of atypical hyperplasia,adenoma,carcinoma in situ and adenocarcinoma of lung in LSL K-ras G12D transgenic mice at different pathological stages.Lung tissue samples were taken and observed by HE staining.Immunohistochemistry were used to detect the expression of somatostatin receptor 2(SSTR2).Real-time fluorescence quantitative PCR was used to detect miR-155 expression levels in lung xenograft models and transgenic mice at different stages of lung cancer.Then CS-miR-155-MB and CS-miR-155-MB-OCT were injected via tail vein in lung xenograft models.CS-miR-155-MB-OCT was injected via tail vein in transgenic mice models.The fluorescence signals of lung in nude mice and transgenic mice at different disease stages were imaged by living imaging system.Frozen slices of lung tissue were made.The source of fluorescence signal was detected by laser confocal scanning microscope(CLSM).Results HE staining showed that lung transplantation tumor models and lung cancer models of atypical hyperplasia,adenoma,carcinoma in situ and lung adenocarcinoma at different pathological stages were successfully constructed.Immunohistochemical analysis showed somatostatin receptor 2(SSTR2)was expressed in transplanted lung tumor and tissue at different pathological stages.In transgenic mouse models,the expression of miR-155 was gradually increased as the disease progressed(P＜0.05).In lung xenograft models,the fluorescence signals were significantly higher in the CS-miR-155-MB-OCT group than those of the CS-miR-155-MB group(P＜0.05).In transgenic mouse models,the fluorescence signals gradually increased with the gradual progression of lesions(P＜0.05).After re-imaging the lung tissue,it was found that the fluorescence signal came from lung,and CLSM showed that the fluorescence signal came from cancer cells and some normal alveolar epithelial cells.Conclusion CS-miR-155-MB-OCT can dynamically reflect the occurrence and development of lung cancer according to changes of different fluorescence intensity,thus providing a new technology for the early diagnosis of lung cancer.

Objective To establish the methods of galvanic vestibular stimulation-vestibular evoked myogenic potentials(GVS-VEMPs)in healthy children and to obtain the normal value of GVS-cVEMP and GVS-oVEMP in these children in China.Methods Twenty(3～14 years)healthy children and 24 healthy adults(18～30 years)were enrolled for conventional examinations of GVS-cVEMP and GVS-oVEMP.Using the galvanic stimulation in-tensity under 3 mA/1 ms for children and 5 mA/1 ms for adults.The characteristics of elicitation and parameter re-sults of GVS-cVEMP and GVS-oVEMP in children and adults,as well as the pain scores and the elicitation of differ-ent stimulus intensities in the two age groups were recorded.Results The elicitation of GVS-cVEMP and GVS-oVEMP were both 100.0％in children and adult groups.The p1 latency,n1 latency and p1-n1 interval latency of GVS-cVEMP were 10.46±1.84 ms,16.98±2.12 ms and 6.52±1.42 ms respectively in children group,the n1 la-tency and p1-n1 interval latency were significantly shorter than the adult group(P＜0.05).The n1 latency,p1 la-tency and p1-n1 interval latency of GVS-oVEMP were 8.87±1.40 ms,12.25±1.80 ms and 3.39±1.07 ms re-spectively in children group with no significant difference between the two groups.The thresholds of GVS-cVEMP and GVS-oVEMP in children group were significantly lower than adult group(P＜0.01),but no differences were found in adult group regarding on the amplitude and interaural amplitude asymmetry ratio.In addition,with the in-crease of the intensity of galvanic stimulation,the correlation between pain scores and the elicitation rates of GVS-cVEMP and GVS-oVEMP also increased.Conclusion Using appropriate stimulus intensity and recording methods,GVS-cVEMP and GVS-oVEMP could be successfully assessed and detected in healthy children over 3 years old and adolescents.The latency of GVS-cVEMP in children is slightly shorter than that in adults,therefore we recommend selecting the matched age group for assessment in the children group.

Objective To explore the changes in peripheral blood interleukin-23(IL-23)/IL-17A axis and microRNA-365-5p(miR-363-5p)in patients with neuromyelitis optica spectrum disorder(NMOSD)before and after treatment with rituximab.Methods NMOSD patients were divided into aquaporin-4 immunoglobulin G(AQP-4IgG)positive group and AQP-4IgG negative group based on the presence of AQP-4IgG antibodies.Both groups received continuous treatment with rituximab(PTX)for over one year.The therapeutic effect of the two groups was compared,and the annual recurrence times,ADL scores and peripheral blood expression levels of IL-23,IL-17A and miR-363-5p were compared before treatment and 12 months after treatment,and the occurrence of adverse drug reactions were recorded.Results AQP-4IgG positive group and AQP-4IgG negative group included 73 cases and 27 cases respectively.The clinical therapeutic effect of AQP-4IgG positive group and AQP-4IgG negative group was 84.93％and 70.37％,with no statistical significance(P＞0.05).Before treatment,the annual recurrence times of AQP-4IgG positive group and AQP-4IgG negative group were(1.36±0.32)and(1.33±0.41)times per year,the ADL scores were(62.36±5.76)and(63.27±5.38)points,IL-23 were(325.23±116.35)and(328.79±120.38)pg·mL-1,IL-17A were(68.46±12.38)and(69.61±13.41)pg·mL-1,miR-363-5p were 1.76±0.10 and 1.77±0.19,respectively.After 12 months of treatment,the annual recurrence times of AQP-4IgG positive group and AQP-4IgG negative group were(0.28±0.16)and(0.31±0.12)times per year,ADL scores were(85.10±10.36)and(81.26±11.34)points,IL-23 were(122.46±11.54)and(119.49±10.26)pg·mL-1,IL-17A were(43.16±6.29)and(40.27±8.75)pg·mL-1,miR-363-5p were 1.38±0.15 and 1.36±0.15,respectively.There were statistically significant differences in the above indexes between the two groups after treatment and before treatment(all P＜0.05),but no significant differences between the groups post-treatment(all P＞0.05).The incidence rates of adverse drug reactions were 13.69％in the AQP-4IgG positive group and 18.51％in the negative group,with no statistically significant difference(P＞0.05).Conclusion Rituximab is effective in treating NMOSD,reducing the number of annual relapses and promoting the recovery of patients'mobility.The mechanism may be related to regulating the IL-23/IL-17A axis and inhibiting the expression of miR-363-5p.

Objective By population survey,to explore the epidemiological characteristics of gastric precancerous lesions in Lishui District of Nanjing and provide objective basis for the prevention and treatment of early gastric cancer.Methods From July 2021 to December 2022,21 977 patients who received endoscopy and/or 13C-UBT in Lishui District People's Hospital and 6 medical community units in Nanjing City were retrospectively analyzed for demography characteristics,detection rate of gastric precancerous lesions,and H.Pylori infection rate.Results(1)590 cases of gastric precancerous lesions were detected(detection rate 2.68%);(2)The total detection rate of precancerous lesions and three pathological types in males were all higher than those in females(all P<0.001);(3)The minimum age for the total detection rate of precancerous lesions in males and the mini-mum age for each pathological type were lower than in females(P<0.001,0.009,0.005,0.002);(4)The popu-lation total H.pylori infection rate was 23.10%,the H.pylori infection rate in patients with precancerous lesions was higher than that in non-precancerous lesions(P<0.001),both H.pylori infection rate of male and female in precancerous lesions were all higher than those of non-precancerous lesions of the same sex(all P<0.001),in addition,the H.pylori infection rate of male whether in precancerous or non-precancerous lesions was higher than that of female(all P<0.001);(5)The precancerous lesions detection rate in male,female,and the overall age range of 20～29 to 70～79 years is positively correlated with age growth(P<0.001),and rapidly decreases after the age of 79,the of H.pylori infection rate was also positively correlated with age growth(P<0.001),and the trend of age change(P<0.001)was parallel to the precancerous lesions detection rate.Conclusions The detec-tion rate of gastric precancerous lesions in this region is above the average level in China;the total H.pylori infec-tion rate is at a relatively low level in China;the H.pylori infection rate is parallel to the age trend of the detection rate of gastric precancerous lesions,and increases with age.

Objective To investigate the bacterial contamination status and risk factors of sterile lamp handle used during open spinal surgery in clean laminar flow operating room at different time periods,so as to provide basis for timely replacement of lamp handle and implementation of intervention measures.Methods A total of 275 sterile lamp handles used during open spinal surgery in clean laminar flow operating room were selected as the research objects,and the outer surface of the lamp handle was sampled with sterile cotton swab,and the bacteria detection and risk factors of the lamp handle at different time periods were analyzed.Results Among 275 sterile lamp handles used during open spinal surgery,41(14.91%)lamp handles detected bacteria from 3 hours after operation;and 53 strains of bacteria were cultured,among which 17 strains(32.08%)were Escherichia coli,accounting for the highest proportion.Univariate and multivariate Logistic regression analysis showed that complicated open trauma,operation time≥5 hours,intraoperative blood loss≥400 mL,intraoperative use of sterile lamp handle against the lamp≥10 times,obvious blood contamination of lamp handle and number of operating room personnel≥8 were the risk factors leading to the detection of bacteria in lamp handle(OR>1,P<0.05).Conclusion The bacterial contamination of sterile lamp handle used during open spinal surgery in clean laminar flow operating room is mainly caused by Escherichia coli.The bacterial contamination of the lamp handle is related to open trauma,operation time,amount of blood loss,number of sterile lamp handle used against the lamp,obvious blood contamination of lamp handle and number of operating room personnel,etc.It is suggested that the lamp handle should be replaced when the operation time is longer than 3 hours.

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.