RESUMO
Veterinary education is the foundation of veterinary services in the country. Starting from the service sector in the army, veterinary education and practice in Thailand have been standardized and progressed toward international veterinary standards. The 6-year Doctor of Veterinary Medicine core curriculum is deployed to develop the curriculum for each Veterinary Education Establishment (VEE). The challenges for veterinary education and practices reflect the country's expectations of veterinary services. With regional and global collaboration, the VEEs have been developing tools and learning platforms for delivering qualified veterinary graduates that fit fast-growing society needs.
Assuntos
Educação em Veterinária , Animais , Tailândia , AprendizagemRESUMO
Therapy of Burkholderia pseudomallei acute infections is largely limited to a few ß-lactam antibiotics such as ceftazidime or meropenem. Although relatively rare, resistance emergence during therapy leads to treatment failures with high mortality rates. In the absence of acquired external resistance determinants in B. pseudomallei emergence of ß-lactam resistance is invariably caused by mutational modification of genomically encoded factors. These include the deletion of the ceftazidime target penicillin-binding protein 3 or amino acid changes in the Class A PenA ß-lactamase that expand its substrate spectrum, as well as penA gene duplication and amplification or its overexpression via transcriptional up-regulation. Evidence is presented that penA is co-transcribed with the upstream nlpD1 gene, that the transcriptional terminator for nlpD1 serves as a penA attenuator and that generation of a new promoter immediately upstream of the terminator/attenuator by a conserved G to A transition leads to anti-termination and thus constitutive PenA expression and extended ß-lactam resistance. Further evidence obtained with the extensively ß-lactam resistant clinical isolate Bp1651 shows that in addition to PenA overexpression and structural mutations other adaptive mechanisms contribute to intrinsic and acquired B. pseudomallei ß-lactam resistance.
Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Burkholderia pseudomallei/genética , Lipoproteínas/genética , Melioidose/tratamento farmacológico , Resistência beta-Lactâmica/genética , beta-Lactamases/genética , Antibacterianos/uso terapêutico , Proteínas de Bactérias/metabolismo , Burkholderia pseudomallei/efeitos dos fármacos , Ceftazidima/farmacologia , Ceftazidima/uso terapêutico , Duplicação Gênica/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/genética , Genes Bacterianos/efeitos dos fármacos , Genes Bacterianos/genética , Interações Hospedeiro-Patógeno/genética , Humanos , Lipoproteínas/metabolismo , Melioidose/microbiologia , Meropeném/uso terapêutico , Testes de Sensibilidade Microbiana , Mutação/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Processamento Pós-Transcricional do RNA , RNA Bacteriano/genética , Regulação para Cima/efeitos dos fármacos , Resistência beta-Lactâmica/efeitos dos fármacos , beta-Lactamases/metabolismoRESUMO
One hundred Acinetobacter baumannii clinical isolates were examined for inhibitory effect of reserpine and carbonyl cyanide m-chlorophenylhydrazone (CCCP) on the antimicrobial susceptibility and expression of 4 resistant-nodulation-cell division (RND)-type multidrug efflux systems, including AdeABC, AdeDE, AdeIJK, and AdeFGH, using RT-PCR. Ten A. baumannii isolates expressing AdeABC, AdeIJK, or AdeFGH were randomly selected for determination of transcription level and regulatory mutations. While all the isolates were resistant to multiple drugs, the reserpine and CCCP experiment showed that the multidrug resistance phenotype in most A. baumannii isolates was associated with efflux pumps. Most isolates expressed at least one of the RND-type efflux pumps tested (97%). AdeIJK expression was most common (97%), but none of the isolates produced AdeDE. Fifty-two percent of the A. baumannii isolates simultaneously produced up to 3 RND-type efflux systems (i.e., AdeABC, AdeFGH, and AdeIJK). No good correlation between the expression of RND-type efflux pumps and the type of antimicrobial resistance was observed. Overexpression of AdeABC, AdeIJK, and AdeFGH was not always related to the presence of mutations in their corresponding regulatory genes. This study highlights (i) the universal presence of the RND-type efflux pumps with variable levels of expression level among the A. baumannii in this collection and (ii) the complexity of their regulation of expression.