RÉSUMÉ
Background & objectives: Overexpression of efflux pumps is a cause of acquired resistance to fluoroquinolones in Acinetobacter baumannii. The present study was done to investigate the presence and overexpression of AdeABC efflux system and to analyze the sequences of AdeR-AdeS regulatory system in ciprofloxacin-resistant A. baumannii isolates. Methods: Susceptibility of 50 clinical A. baumannii isolates to ciprofloxacin, imipenem, ceftazidime, cefepime and gentamicin antimicrobials was evaluated by agar dilution method. Isolates were screened for the evidence of active efflux pump. Isolates were also examined for adeR-adeS and adeB efflux genes by polymerase chain reaction (PCR). The adeR and adeS regulatory genes were sequenced to detect amino acid substitutions. Expression of adeB was evaluated by quantitative reverse-transcriptase PCR. Results: There were high rates of resistance to ciprofloxacin (88%), ceftazidime (88%), cefepime (74%) and imipenem (72%) and less resistance rate to gentamicin (64%). Phenotypic assay showed involvement of active efflux in decreased susceptibility to ciprofloxacin among 16 isolates. The 12.27-fold increase and 4.25-fold increase were found in adeB expression in ciprofloxacin-full-resistant and ciprofloxacin-intermediate-resistant isolates, respectively. Several effective mutations, including A91V, A136V, L192R, A94V, G103D and G186V, were detected in some domains of AdeR-AdeS regulators in the overexpressed ciprofloxacin-resistant isolates. Interpretation & conclusions: The results of this study indicated that overexpression of the AdeABC efflux pump was important to reduce susceptibility to ciprofloxacin and cefepime in A. baumannii that, in turn, could be triggered by alterations in the AdeR-AdeS two-component system. However, gene expression alone does not seem adequate to explain multidrug resistance phenomenon. These results could help plan improved active efflux pump inhibitors.
RÉSUMÉ
Objective To detect the distribution of resistance-nodulation (RND)efflux pump system of Acineto-bacter baumannii (AB),and explore the relationship between its’expression and antimicrobial resistance.Methods Fifty-nine strains of multidrug-resistant AB isolated from clinical specimens in The First Affiliated Hospital of Nan-chang University were identified and performed antimicrobial susceptibility analysis,distribution of RND efflux sys-tem of AB was detected by polymerase chain reaction(PCR),expression of efflux pump genes in different drug-re-sistant phenotypes of AB was compared,relationship between the expression level and drug resistance was analyzed, amplified products of RND efflux system were sequenced.Results Resistance rates of AB to ampicillin/sulbactam, imipenem,gentamicin,ciprofloxacin,and levofloxacin were 93.2%,94.9%,88.1%,96.6%,and 52.5% respec-tively.PCR detection results of efflux pump and integron genes of 59 AB strains revealed that the carrying rates of adeR,adeS,adeB,adeJ,and adeG genes were 81.4%,91.5%,93.2%,100.0%,and 61.0% respectively.The expression of efflux pump genes in different strains was different,expression levels of ade B and adeJ genes among gentamicin,imipenem,ampicillin/sulbactam resistant AB group and non-resistant AB group were significantly dif- ferent (all P＜0.05).There was no mutation or insertion sequence in the base sequences of regulatory genes ade R and ade S of adeABC efflux pump.Conclusion RND efflux pump system is universally present in AB,the expres-sion upregulation of ade B and ade J genes in RND efflux pump system is related with antimicrobial resistance of bacteria to gentamycin,imipenem,and ampicillin-sulbactam.
RÉSUMÉ
Introducci¢n: existe en Colombia poco conocimiento respecto a los facto- res asociados con la adherencia al ejercicio. Objetivo: evaluar los factores asociados con la adherencia a la actividad f¡sica en el tiempo libre (AFTL) de los adultos que participan en un programa de actividad f¡sica (AF). M- todos: se realiz¢ un estudio prospectivo de Casos y Controles. Se defini¢ como caso a quien realiz¢ durante un periodo de 5 meses un promedio 150 minutos o m s de AFTL por semana a una intensidad moderada ¢ 75 minutos a una intensidad vigorosa; como control se tom¢ a quien no cum- pli¢ con los anteriores requisitos. Se evaluaron variables independientes sociodemogr ficas, factores de riesgo cardiovascular y osteomuscular, y las motivacionales para la pr ctica del ejercicio. Los datos se analizaron por medio de un modelo de regresi¢n log¡stica multivariado. Resultados: la muestra la conformaron 176 personas usuarias de un programa de AF, en su mayor¡a mujeres (69,3%); el promedio de edad fue de 55,7 a¤os. Las variables asociadas con la adherencia a la AFTL fueron el antecedente personal de artrosis (OR 0,392; IC95% 0,184-0,837; p=0,016) y la edad (OR 1,027; IC95% 1,001-1,054; p=0,041), las cuales explicaron el 8,0% de la variabilidad. Conclusiones: las variables que se asociaron en forma independiente con la adherencia a la AFTL fueron la edad y el anteceden- te personal de artrosis. Se requiere realizar nuevos estudios que incluyan otras variables que puedan explicar en forma m s global este fen¢meno.
IntroduÆo: Existe na Colmbia pouco conhecimento a respeito dos fatores associados com a aderncia ao exerc¡cio. Objetivo: Avaliar os fatores associados com a aderncia atividade f¡sica no tempo livre (AFTL) dos adultos que participam em um programa de atividade f¡sica (AF). Mtodos: Se realizou um estudo prospectivo de casos e controles. Definiu-se como caso a quem realizou durante um per¡odo de 5 meses em mdia 150 minutos ou mais de AFTL por semana, a uma intensidade moderada ou 75 minutos a uma intensidade vigorosa; como controle tomou-se a quem nÆo cumpriu com os requisitos anteriores. Avaliou-se vari veis independentes s¢cios demogr ficas, fatores de risco cardiovascular, osteomuscular e as motivaães para a pr tica de exerc¡cios. Analisaram-se os dados por meio de um modelo de regressÆo log¡stica multivariado. Resultados: conformaram a amostra 176 pessoas usu rias de um programa de AF, em sua maioria mulheres (69,3%); a mdia de idade foi de 55,7 anos. As vari veis associadas com a aderncia a AFTL foram o antecedente pessoal de artrose (OR 0,392; IC95% 0,184-0,837; p=0,016) e a idade (OR 1,027; IC95% 1,001-1,054; p=0,041), os quais explicaram os 8% de variabilidade. Conclusães: As vari veis que se associaram de forma independente com a aderncia AFTL foram a idade e o antecedente pessoal de artrose. Faz-se necess rio realizar novos estudos que incluam outras vari veis que possam explicar de forma mais global este fenmeno.
Introduction: In Colombia there is a low knowledge related to the associated factors with adherence to exercise. Objective: To evaluate the associated factors with adherence to the physical activity in leisure time in adults (PALT) who participate in a physical activity program. Methods: The study was a prospective case-control. A case was defined as who performed during five months an average of 150 minutes or more per week of PALT, with a moderate intensity or strong intensity of 75 minutes or more of PALT per week; as a control was had in consideration, people who did not meet the above criteria. The independent variables measured were: socio-demographic factors, cardiovascular, musculoskeletal risk factors, and the motivation to exercise. The data was analyzed through a varied regressive logistic model. Results: The sample involved 176 female users of a PA program (69.3%); with an average age of 55.7 years old. The associated variables with the PALT adherence were the personal osteoarthritis record (OR 0,392; IC95% 0,184 0,837; P=0,016) and the age (OR 1,027; IC95% 1,001-1,054; p=0,041), which explained 8, 0 % of the variability. Conclusions: The variables that were independently associated to the adherence to PALT were age, and the personal osteoarthritis record. There is a necessity of new studies that include new variables to allow a global analysis of the phenomena.