Objective The pathogenic characteristics of Escherichia coli(E.coli)in bacterial infections were analyzed using a combination of multiple molecular typing techniques in order to provide evidence for the management of clinical medication safety.Methods Samples from some bacterial infection-related cases in a district of Chongqing in 2021 were collected.A total of 30 E.coli strains were selected by a completely random method,and phoA gene PCR assay was performed for identification.Molecular typing of the strains was analyzed using pulsed-field gel electrophoresis(PFGE)and multilocus sequence typing(MLST).Antimicrobial susceptibility testing was conducted to determine the drug resistance of the strains,and four β-lactamase-encoding genes(blaCTX-M,blaTEM,blaSHV,blaZ)were selected to detect the carriage of resistance genes.Results All 30 E.coli strains displayed the phoA gene target band.Their PFGE banding patterns,with a similarity of 50%～98%,could be classified into 8 clusters.Cluster C was the dominant group,accounting for 53.3%(16/30).C1 and C2 exhibited high genetic correlation,indicating a close phylogenetic relationship.One E.coli strain could not be assigned a sequence type(ST)by MLST,while the remaining 29 E.coli isolates were classified into 16 different STs,demonstrating a polymorphic distribution.Among them,10 isolates belonged to ST131(10/30,33.33%).Evolutionary analysis of the 10 ST131 E.coli strains revealed their distribution across different branches,indicating varying degrees of genetic relatedness.Antimicrobial susceptibility testing revealed that all 30 E.coli strains exhibited varying degrees of resistance,with the highest resistance rate observed against the β-lactam antibiotic ampicillin(25/30,83.33%).Among them,60.0%were multidrug-resistant bacteria(MDRB).These MDRB strains exhibited 16 distinct resistance profiles,displaying a scattered distribution without a dominant resistance pattern.50.0%(9/18)of the MDRB strains exhibited six-drug resistance,while the most drug-resistant strain showed eight-drug resistance.Furthermore,the blaCTX-M gene carriage rate among the 30 E.coli strains was 86.67%(26/30),while no blaZ gene was detected.Conclusion E.coli related to bacterial infections from a Chongqing district exhibited diverse PFGE/MLST patterns and significant drug resistance.The application of multiple molecular typing techniques can reveal the genetic diversity,evolutionary relationships,and antimicrobial resistance characteristics of pathogenic bacteria.Countermeasures It is recommended to enhance the molecular typing and drug resistance surveillance network for pathogenic bacteria,establish an early warning mechanism,and implement hierarchical management of antibiotics,thereby improving targeted prevention and epidemic traceability capabilities for key drug-resistant bacteria such as ST131.

Objective To understand the serotype,molecular typing and drug sensitivity characteristics of Salmonella isolated from food and stool samples of diarrhea patients in Nan'an District of Chongqing.Methods A total of 71 Salmonella strains isolated from food and stool samples of diarrhea patients in Nan'an District of Chongqing from 2019 to 2022 were serotyped,and the drug resistance of the strains was determined by the micro-broth dilution method.Multilocus sequence typing(MLST)was performed on 2 Salmonella Ken-tucky strains,and whole genome sequencing was performed on 8 Salmonella typhimurium strains and 2 Sal-monella typhimurium variants.Results The 71 strains of Salmonella included 13 serotypes.A total of 48 Sal-monella strains were isolated from stool samples of diarrhea patients,with Salmonella typhimurium(56.25％,27/48)and Salmonella enteritidis(18.75％,9/48)as the main serotypes.A total of 23 Salmonella strains were isolated in food samples,with Salmonella Rissen(26.09％,6/23)as the predominant.The total drug re-sistance rate of 71 strains of Salmonella was 97.18％.The highest drug resistance rate was ampicillin(69.01％),followed by tetracycline(64.79％),compound sulfamethoxazole(43.66％)and chloramphenicol(43.66％).The multidrug resistant strains accounted for 61.97％(44/71),including 60.42％(29/48)of stool samples of diarrhea patients and 65.22％(15/23)of food samples.The two Salmonella Kentucky strains iso-lated from food and diarrhea patients were resistant to 7 and 8 types,respectively,with the largest number of drug resistant types in the corresponding samples.The MLST types of both Salmonella Kentucky strains was ST198 type.The MLST types of 8 Salmonella typhimurium strains selected for sequencing were ST19,and the MLST types of 2 Salmonella typhimurium monophasic variants were ST34.The genetic relationship of Salmo-nella typhimurium with the same ST type was different.Conclusion The serotypes of Salmonella isolated from Nan'an District of Chongqing are diverse and the drug resistance is serious.The detection of ST198 Sal-monella Kentucky is more accurate by using whole genome sequencing than MLST.The surveillance of Sal-monella serotypes,molecular typing and drug resistance should be strengthened.

Objective To investigate the value of differentiating dermatofibrosarcoma protuberans(DFSP)from neurofibroma(NF)based on MR apparent diffusion coefficient(ADC)value.Methods The enhanced MR images data of 50 patients with patho-logically or clinically confirmed DFSP(36 patients)and NF(14 patients)were analyzed retrospectively.Clinical data and characteris-tics of conventional and functional MRI,including maximum diameter,margin,depth of invasion,enhancement pattern,and ADC value,were evaluated and compared between the two groups.Chi square test,independent samples t-test or Mann-Whitney U test were used to select statistically significant parameters.New diagnostic models were established via binary logistic regression analysis.The receiver operating characteristic(ROC)curves were drawn to evaluate the diagnostic performance of these models.Results Univariate diag-nostic models were developed based on age,maximum diameter,and ADC value,while the combined model was established by logis-tic regression analysis.The area under the curve(AUC)of these models were 0.756,0.837,0.826 and 0.923,with sensitivities of 88.89%,80.56%,86.11%and 91.67%,and specificities of 64.29%,85.71%,78.57%and 92.86%,respectively.Conclusion The combined model based on ADC value,age,and maximum diameter is highly valuable for differential diagnosis between DFSP and NF.

Objective To analyze the serotypes of enteroviruses(EVs) isolated from patients with influenza-like illness in Beijing in 2017. Methods Oropharyngeal swab specimens were collected from pa-tients with influenza-like illness in eight districts of Beijing from July 2017 to October 2017. EVs were detec-ted by real-time PCR. Specific primers were synthesized and used to amplify the VP1 fragments of EVs. PCR products were sequenced and the results were compared with the reference sequences by using Basic Lo-cal Alignment Search Tool(BLAST) to identify the serotypes of isolated EVs. Results A total of 666 spec-imens were collected and 91 (13.66%) were positive for EVs. VP1 sequences of 66 EVs were successfully amplified and BLAST analysis revealed that these strains belonged to 14 serotypes,including seven serotypes of EV-A species,six serotypes of EV-B species and one serotype of Rhinovirus species. The predominant se-rotypes were CVA2 and CVA6. Eight out of 14 CVA6 strains that were collected in Shunyi District shared high homology. All seven CVB5 strains were collected in Shijingshan District and grouped into one cluster. Conclusion EVs causing influenza-like illness in Beijing in 2017 belonged to 14 serotypes and CVA2 and CVA6 were the predominant serotypes.

Objective To explore the effect of low frequency repetitive transranial magnetic stimulation (rTMS) on unilateral spatial neglect (USN). Methods 40 stroke patients with USN were divided into treatment group (n=20) and control group (n=20). Patients in the treatment group were treated with low frequency rTMS for 2 weeks. The USN degree of these groups were evaluated before and after the treatment. Results There was no significant difference of USN degree between these groups before the treatment (P>0.05); Compared with the control group, the treatment group improved significantly after the treatment (P<0.05). The USN degree of patients in the treatment group decreased significantly after the treatment (P<0.05), while patients in the controlled group had no difference (P>0.05). Conclusion USN induced by stroke could be improved obviously through low frequency rTMS.

A 33-year-old male patient with tick-borne encephalitis (TBE) was reviewed, who presented with severe neurological deficits following TBEV infection, and improved in his motor and quality of life after an individualized rehabilitation.