Objective:To investigate the mechanisms of quinolone resistance and the association with other resistance markers among Esherichia coli(E.coli) strains isolated from outpatient with urinary tract infection in north of...Objective:To investigate the mechanisms of quinolone resistance and the association with other resistance markers among Esherichia coli(E.coli) strains isolated from outpatient with urinary tract infection in north of Algeria.Methods:A total of 30 nalidixic acid-resistant E.coli isolates from outpatient with urinary tract infections from January 2010 to April 2011 in north of Algeria(Bejaia) were studied.Antimicrobial susceptibility was determined by disc diffusion assay,minimal inhibitory concentrations(MIC) of quinolone were determined by microdilution.Mutations in the Quinolone Resistance-Determining Region(QRDR) of gyra and parC genes and screening for qnr(A,B and S) and bla genes were done by PCK and UNA sequencing.Results:Most of the E.coli isolates(56.66%) were shown to carry mutations in gyrA and parC,igyra:Ser83Leu + Asp87Asn and parC:Ser80Iler.While.16.66 had only an alteration in gyrA:Ser83Leu.One isolate produced qnrB-like and two qnrS-like.Four isolates were CTXM-15 producers associated with TEM-1 producing in one case.Co-expression of bla_(LTV,M)_(15) and qnrB was determined in one E.coli isolate.Conclusions:Our findings suggested the community emergence of gyrA and parC alterations and Qnr determinants that contributed to the development and spread of fluoroquinolone resistance in Algerian E.coli isolates.展开更多
Distribution of Sm and Ce in mice was investigated after inhalation exposure to their oxide particles of 5 μm diameter and 15 mg/m3.Sm and Ce were mainly distributed in lung,their concentrations decreased with passin...Distribution of Sm and Ce in mice was investigated after inhalation exposure to their oxide particles of 5 μm diameter and 15 mg/m3.Sm and Ce were mainly distributed in lung,their concentrations decreased with passing time,and their concentrations in lung were correlated with exposure periods.Concentrations of Ce were lower than that of Sm in each point.Sm was also distributed in the other organs and bone but Ce was scarcely detected.These results suggest that the behaviors of Sm and Ce inhaled were different,although their chemical properties are similar.展开更多
文摘Objective:To investigate the mechanisms of quinolone resistance and the association with other resistance markers among Esherichia coli(E.coli) strains isolated from outpatient with urinary tract infection in north of Algeria.Methods:A total of 30 nalidixic acid-resistant E.coli isolates from outpatient with urinary tract infections from January 2010 to April 2011 in north of Algeria(Bejaia) were studied.Antimicrobial susceptibility was determined by disc diffusion assay,minimal inhibitory concentrations(MIC) of quinolone were determined by microdilution.Mutations in the Quinolone Resistance-Determining Region(QRDR) of gyra and parC genes and screening for qnr(A,B and S) and bla genes were done by PCK and UNA sequencing.Results:Most of the E.coli isolates(56.66%) were shown to carry mutations in gyrA and parC,igyra:Ser83Leu + Asp87Asn and parC:Ser80Iler.While.16.66 had only an alteration in gyrA:Ser83Leu.One isolate produced qnrB-like and two qnrS-like.Four isolates were CTXM-15 producers associated with TEM-1 producing in one case.Co-expression of bla_(LTV,M)_(15) and qnrB was determined in one E.coli isolate.Conclusions:Our findings suggested the community emergence of gyrA and parC alterations and Qnr determinants that contributed to the development and spread of fluoroquinolone resistance in Algerian E.coli isolates.
基金Project partially supported by the Grant-in-Aid for Scientific Research (c)21590665,JSPS,Japan
文摘Distribution of Sm and Ce in mice was investigated after inhalation exposure to their oxide particles of 5 μm diameter and 15 mg/m3.Sm and Ce were mainly distributed in lung,their concentrations decreased with passing time,and their concentrations in lung were correlated with exposure periods.Concentrations of Ce were lower than that of Sm in each point.Sm was also distributed in the other organs and bone but Ce was scarcely detected.These results suggest that the behaviors of Sm and Ce inhaled were different,although their chemical properties are similar.
