Objective To explore the effects and mechanisms of bone marrow mesenchymal stem cells(BMSCs)in regulating microglial polarization on neuropathic pain in rats with sciatic nerve branch-selective injury(SNI).Methods Fifty SD rats were randomly divided into five groups with ten rats in each group;sham group(rats only exposed sciatic nerve without ligation),SNI group(SNI model was estab-lished),BMSCs group[rats were injected with BMSCs(1×106)through the sheath for 3 days after SNI modeling],BMSCs+sh-NC group[rats were intrathecally injected with BMSCs(1×106)and intrathecally injected with knock-down control(adenovirus 2.5×107 IU)for 3 days after SNI modeling],and BMSCs+sh-YY1 group[rats were intrathecally injected with BMSCs(1×106)and intrathecally injected with YY1 knockdown adenovirus(2.5×107 IU)for 3 days after SNI modeling].Neuropathic pain was assessed using paw withdrawal threshold(PWT)and paw withdrawal thermal latency(PWTL)following mechanical stimulation.Immunofluorescence was used to detect the expression of CD86,CD206,iNOS,and Arg1 in the rat spinal cord tissues.Western blotting was used to measure the expression of YY1 and KLF4 in spinal cord tissue.Results Compared with sham group,the values of PWTL and PWT in the SNI group significantly reduced(both P<0.05).In spinal cord tissue,the positive rates of iNOS and CD86 protein increased,whereas the positive rates of CD206 and Arg1 protein and the expression of YY1 and KLF4 decreased(all P<0.05).Compared with the SNI group,the values of PWTL and PWT in the BMSCs and BMSCs+sh-NC groups increased(all P<0.05),the positive rate of CD86 protein in the spinal cord decreased,whereas the positive rate of CD206 protein and the expression of YY1 and KLF4 increased(all P<0.05).Also,the positive rate of iNOS protein in the spinal cord tissue decreased and the positive rate of Arg1 increased in the BMSCs group(all P<0.05).Compared with the BMSCs and BMSCs+sh-NC groups,the PWTL and PWT values in the BMSCs+sh-YY1 group decreased(all P<0.05).The positivity rate of CD86 protein increased,the positivity rate of CD206 protein decreased,and the expression of YY1 and KLF4 decreased in the spinal cord tissue(all P<0.05).Conclusion Intrathecal injection of BMSCs promotes M2 polarization of microglia in the spinal cord and relieves neuropathic pain in rats with SNI,and its mechanism may be related to the upregulation of KLF4 expression mediated by YY1.

OBJECTIVE T o assess the in vitro antimicrobial activity of aztreonam-avibactam against metallo-β—lacta-mase(MBL)-producing carbapenem-resistant Enterobacteriaceae(CRE)using different antimicrobial susceptibility testing methods,evaluate the consistency of results based on the latest breakpoints recommended by European Committee on Antimicrobial Susceptibility Testing(EUCAST),and analyze the clinical applicability.METHODS The imipenem-or meropenem-resistant Enterobacteriaceae strains were isolated from the clinical specimens of Bei-jing Chaoyang Hospital from Jan.2019 to Mar.2023,MBL-producing CRE were selected after they were con-firmed by colloidal gold immunoassay and Sanger sequencing as the study subjects.The minimum inhibitory con-centrations(MICs)of single aztreonam and aztreonam-avibactam compounds were determined by using broth mi-crodilution method.In addition,the disk diffusion method and the gradient diffusion method were employed to further detect the in vitro susceptibility to aztreonam-avibactam.RESULTS Among the 87 strains of MBL-producing CRE that were included in the study,Escherichia coli was the most common species,accounting for 44.83％.NDM-5 was the predominant carbapenemase type,detected in 48.28％of the isolates.According to the latest EUCAST break-points,6 isolates were aztreonam-avibactam-resistant strains based on broth microdilution method,all of which were E.coli,and the resistance rate was 6.90％(6/87).However,the resistance rate that was determined by the disk diffu-sion method was significantly higher(22.99％,20/87).Among these,14 strains was within the area of technical uncer-tainty/resistant,making result interpretation difficult.In addition,the categorical agreement between the gradient diffu-sion method and the broth microdilution method reached up to 98.85％.CONCLUSIONS Aztreonam-avibactam has high antimicrobial activity against MBL-producing CRE.However,based on the latest EUCAST breakpoints,the antimicrobial susceptibility testing by the disk diffusion method results of some strains are hard to interpret.It is necessary to integrate with other methods for further validation.

Objective To explore the effects and mechanisms of bone marrow mesenchymal stem cells(BMSCs)in regulating microglial polarization on neuropathic pain in rats with sciatic nerve branch-selective injury(SNI).Methods Fifty SD rats were randomly divided into five groups with ten rats in each group;sham group(rats only exposed sciatic nerve without ligation),SNI group(SNI model was estab-lished),BMSCs group[rats were injected with BMSCs(1×106)through the sheath for 3 days after SNI modeling],BMSCs+sh-NC group[rats were intrathecally injected with BMSCs(1×106)and intrathecally injected with knock-down control(adenovirus 2.5×107 IU)for 3 days after SNI modeling],and BMSCs+sh-YY1 group[rats were intrathecally injected with BMSCs(1×106)and intrathecally injected with YY1 knockdown adenovirus(2.5×107 IU)for 3 days after SNI modeling].Neuropathic pain was assessed using paw withdrawal threshold(PWT)and paw withdrawal thermal latency(PWTL)following mechanical stimulation.Immunofluorescence was used to detect the expression of CD86,CD206,iNOS,and Arg1 in the rat spinal cord tissues.Western blotting was used to measure the expression of YY1 and KLF4 in spinal cord tissue.Results Compared with sham group,the values of PWTL and PWT in the SNI group significantly reduced(both P<0.05).In spinal cord tissue,the positive rates of iNOS and CD86 protein increased,whereas the positive rates of CD206 and Arg1 protein and the expression of YY1 and KLF4 decreased(all P<0.05).Compared with the SNI group,the values of PWTL and PWT in the BMSCs and BMSCs+sh-NC groups increased(all P<0.05),the positive rate of CD86 protein in the spinal cord decreased,whereas the positive rate of CD206 protein and the expression of YY1 and KLF4 increased(all P<0.05).Also,the positive rate of iNOS protein in the spinal cord tissue decreased and the positive rate of Arg1 increased in the BMSCs group(all P<0.05).Compared with the BMSCs and BMSCs+sh-NC groups,the PWTL and PWT values in the BMSCs+sh-YY1 group decreased(all P<0.05).The positivity rate of CD86 protein increased,the positivity rate of CD206 protein decreased,and the expression of YY1 and KLF4 decreased in the spinal cord tissue(all P<0.05).Conclusion Intrathecal injection of BMSCs promotes M2 polarization of microglia in the spinal cord and relieves neuropathic pain in rats with SNI,and its mechanism may be related to the upregulation of KLF4 expression mediated by YY1.

OBJECTIVE T o assess the in vitro antimicrobial activity of aztreonam-avibactam against metallo-β—lacta-mase(MBL)-producing carbapenem-resistant Enterobacteriaceae(CRE)using different antimicrobial susceptibility testing methods,evaluate the consistency of results based on the latest breakpoints recommended by European Committee on Antimicrobial Susceptibility Testing(EUCAST),and analyze the clinical applicability.METHODS The imipenem-or meropenem-resistant Enterobacteriaceae strains were isolated from the clinical specimens of Bei-jing Chaoyang Hospital from Jan.2019 to Mar.2023,MBL-producing CRE were selected after they were con-firmed by colloidal gold immunoassay and Sanger sequencing as the study subjects.The minimum inhibitory con-centrations(MICs)of single aztreonam and aztreonam-avibactam compounds were determined by using broth mi-crodilution method.In addition,the disk diffusion method and the gradient diffusion method were employed to further detect the in vitro susceptibility to aztreonam-avibactam.RESULTS Among the 87 strains of MBL-producing CRE that were included in the study,Escherichia coli was the most common species,accounting for 44.83％.NDM-5 was the predominant carbapenemase type,detected in 48.28％of the isolates.According to the latest EUCAST break-points,6 isolates were aztreonam-avibactam-resistant strains based on broth microdilution method,all of which were E.coli,and the resistance rate was 6.90％(6/87).However,the resistance rate that was determined by the disk diffu-sion method was significantly higher(22.99％,20/87).Among these,14 strains was within the area of technical uncer-tainty/resistant,making result interpretation difficult.In addition,the categorical agreement between the gradient diffu-sion method and the broth microdilution method reached up to 98.85％.CONCLUSIONS Aztreonam-avibactam has high antimicrobial activity against MBL-producing CRE.However,based on the latest EUCAST breakpoints,the antimicrobial susceptibility testing by the disk diffusion method results of some strains are hard to interpret.It is necessary to integrate with other methods for further validation.

Objective:To analyze the early diagnostic value of plasma soluble cluster of differentiation 14 subtype (sCD14-ST, Presepsin) in sepsis in a population with suspected sepsis in fever clinic.Methods:A prospective observational study was conducted. The patients admitted to the fever clinic of Beijing Chaoyang Hospital from April to December 2022 were enrolled as the study objects. According to sequential organ failure assessment (SOFA) score, the patients were divided into low SOFA score group (SOFA score ≤3) and high SOFA score group (SOFA score > 3). Venous blood was collected at the time of admission. The level of plasma Presepsin was detected by chemiluminescence enzyme-linked immunoassay. The level of plasma procalcitonin (PCT) was detected by enzyme-linked immunofluorescence method. The level of C-reactive protein (CRP) was detected by scattering turbidimetry. White blood cell count (WBC) and neutrophil count (NEUT) were measured by automatic blood cell analyzer. For patients with fear of cold or chills, venous blood of upper limbs was taken for blood culture at the time of admission. The differences in inflammatory biomarkers were compared between the two groups. Binary multivariate Logistic regression analysis was used to screen the early risk factors of sepsis in fever outpatients with suspected sepsis. Receiver operator characteristic curve (ROC curve) was drawn to investigate the early diagnostic value of Presepsin and other inflammatory markers in sepsis, and to analyze the optimal cut-off value.Results:A total of 149 fever outpatients with suspected sepsis were enrolled, including 92 patients with low SOFA score and 57 patients with high SOFA score. Plasma PCT and Presepsin levels in the high SOFA score group were significantly higher than those in the low SOFA score group [PCT (μg/L): 0.77 (0.18, 2.02) vs. 0.22 (0.09, 0.71), Presepsin (ng/L): 1?129.00 (785.50, 1?766.50) vs. 563.00 (460.50, 772.25), both P < 0.01]. There was no significant difference in WBC, NEUT, CRP or positive rate of blood culture between the high and low SOFA score groups [WBC (×10 9/L): 11.32±5.47 vs. 11.14±5.29, NEUT (×10 9/L): 9.88±4.89 vs. 9.60±5.10, CRP (mg/L): 54.05 (15.95, 128.90) vs. 46.11 (19.60, 104.60), blood culture positivity rate: 42.3% (11/26) vs. 29.4% (10/34), all P > 0.05]. Multivariate Logistic regression analysis showed that Presepsin was an early risk factor for sepsis in suspected sepsis patients in fever clinics [odds ratio ( OR) = 16.96, 95% confidence interval (95% CI) was 6.35-45.29, P = 0.000]. ROC curve analysis showed that the early diagnostic value of Presepsin in sepsis was significantly better than WBC, NEUT, CRP, PCT, and blood culture [the area under the ROC curve (AUC) and 95% CI: 0.832 (0.771-0.899) vs. 0.522 (0.424-0.619), 0.532 (0.435-0.629), 0.533 (0.435-0.632), 0.664 (0.574-0.753), 0.554 (0.458-0.650)]. When the optimal cut-off value of Presepsin was 646.50 ng/L, its sensitivity and positive predictive value were higher than those of WBC, NEUT, CRP, and PCT (sensitivity: 89.5% vs. 38.6%, 68.4%, 38.6%, 57.9%; positive predictive value: 64.6% vs. 44.9%, 44.3%, 47.8%, 55.9%). Conclusion:Plasma PCT and Presepsin have early diagnostic value for sepsis in suspected sepsis patients in fever clinics, and Presepsin is more sensitive than PCT and can be used as a early marker of sepsis.

Objective: To compare the treatment outcomes for locally advanced hypopharyngeal carcinoma between surgery plus radio(chemo) therapy(SRT) and non-surgery chemoradiotherapy(CRT). Methods: A total of 119 patients diagnosed with advanced hypopharyngeal carcinoma without distant metastases between 2010 and 2014 were identified in the Chinese People′s Liberation Army General Hospital, and they were divided into 2 groups: 42 cases in SRT group and 77 cases in CRT group. Patients′ clinical information was collected. Survival rates and prognostic factors were analyzed by the Kaplan-Meier method with SPSS 23.0 software. The survival rates, laryngeal preservation rates and complication rates were compared between the two groups using the chi-square test.Among the 119 patients, 112 were males and 7 were females. Age ranged from 27 to 78 years, with an average age of 57 years. Results: There were no significant difference between the SRT and CRT group for five-year disease-free survival (DFS, 53.9% vs. 45.1%, χ²=1.251, P=0.263) and overall survival (OS, 54.9% vs. 45.6%, χ²=1.749, P=0.186). Compared to SRT group, CRT group did not showed the significant increase of treatment complications (χ²=0.858, P=0.354), with a higher laryngeal preservation rate (50.0% vs. 71.4%, χ²=6.493, P=0.011). Conclusions Advanced hypopharyngeal carcinoma is of high malignancy and poor prognosis. Combined modality treatment is a main approach for advanced hypopharyngeal cancer. SRT offers disease-free survival and overall survival rates equivalent to CRT, but with a higher laryngeal preservation rate.