Abstract available in the American Journal of Pharmaceutical Education.

N-Thiolated beta-lactams are a new class of anti-MRSA and anti-Bacillus agents that have recently been reported by our laboratories. From previous studies performed in our laboratories, it is believed that the N-thiolated beta-lactams exert their antimicrobial activity through a unique mode of action that is completely unlike that of classical beta-lactam antibiotics. In the first chapter of this dissertation, a review of previously prepared N-thiolated beta-lactam analogues and their mode of action is presented. In the second chapter, the synthesis of seven different C3-oxygenated derivatives is described. These analogues were tested for antibacterial activity against Staphylococcus aureus, nine different strains of MRSA, and seven different species of Bacillus. The results of the antibacterial testing will be discussed in relation to the differences in the structures of the analogues. In chapter 3, the design and synthesis of two new, functionalized caprolactone monomers are presented. FTSThese monomers were subsequently cooligomerized with epsilon-caprolactone, as described in chapter 4. N-thiolated beta-lactams were attached to the functionalized oligomers. These antibiotic containing oligomers were then screened for activity against MSSA, MRSA, and Bacillus. The results of these biological tests and their implications for future experiments are discussed.

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

Probiotics are live microorganisms that are similar to beneficial microorganisms found in the human gut. They are often known as lactic acid bacteria and are normally consumed in the form of yogurt. Most often the bacteria will come from two groups, Lactobacillus and Bifidobacterium. Vancomycin is a bactericidal antibiotic used in the treatment of antibiotic-associated colitis and endocarditis. In this study we will be examining the effects of vancomycin on the induced growth of lactobacilli in the Lewis male rat. The Lewis male rat was used because in the animal model of rheumatoid arthritis, vancomycin was shown to reduce the disease scores of adjuvant-induced arthritis and one research group also noted an increase in lactobacilli growth in the digestive tract with administration. As a control for this research project, to ensure induction of lactobacilli was achieved, Bene-Bac Pet powder was used. Bene-Bac Pet powder contains live, naturally occurring microorganisms and is recommended anytime an animal experiences changing nutritional or environmental conditions, one of them being antibiotic treatment. The rats were placed in four groups, two being control and the others being experimental. According to each group, rats were fed dextrose/maltodextrin substrate, Bene-Bac Pet powder, vancomycin and one group being fed both Bene-Bac powder and vancomycin. Fecal samples were obtained from the rat prior to initial treatment and then once every three days during the experimental period and two days after the conclusion of the experimental procedure (n=5 samples per rat). Samples were diluted and plated and the colony growth was noted. Vancomycin was expected to decrease the growth of lactobacilli in the Lewis rat following the treatments. There were significant changes (p = 0.02) among most groups by day 6 of the study. In contrast, there was an increase in the growth of lactobacilli in experimental groups. Vancomycin increases and maintains the growth of lactobacilli in the Lewis rat. / Department of Physiology and Health Science

Autolysins are enzymes that cleave specific structural components within the bacterial cell wall. They contribute to numerous cellular activities such as cell growth, cell division, peptidoglycan recycling and turnover. In this study, twelve Enterococcal isolates (previously from the genus Streptococcus) were examined for susceptibility to the antibiotics Penicillin G and Vancomycin, using a Disk Diffusion and a Microtitre plate assay. In both methods, all twelve strains were resistant to Vancomycin. Six of these strains were susceptible to Penicillin G. The minimum inhibitory concentration (MIC) values were twice that of the disk diffusion assay values. In the presence of antibiotic, the growth rates for the six strains were halved. Autolysins were extracted from the respective cell cultures using a 4% SDS precipitation method. The protein concentrations were calculated and estimated to be within the range of 5.47- to 6.35 μg/μl. Profiles of the SDS precipitate were analyzed on SDS-PAGE. Autolytic proteins were identified and partially analyzed by renaturing SDS-PAGE (zymograms) using gels containing cell wall substrate. Seven lytic bands of molecular weights 25, 30, 50, 63, 75 95 and 145 kDa (designated Autolysin A to G, respectively) were selected for further analysis. The temporal distribution of the enzymes ranged from the mid exponential phase to the early death phase. The seven proteins were blotted onto polyvinylidene difluoride (PVDF) membranes and excised for N-terminal sequencing. Blast analysis of the respective N-terminal sequences showed autolysins A, C, D, E and F to have 100% similarity to the muramidase, amidase and peptidase from S. cremoris, S. suis, S. pneumonia, S. pyogenes and E. faecium, respectively. Biochemical characterization confirmed autolysins A, B, E and F to exhibit muramidase activity, and autolysin C and G to exhibit peptidase activity. Autolysin D displayed 100% similarity to the protein LytA, a peptidoglycan hydrolase that is known to exhibit amidase activity. Blast analysis could not determine any significant similarities for autolysins B and G to previously identified autolysins, thus indicating they may perhaps be novel autolysins. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.

Tez (Tıpta Uzmanlık) - Süleyman Demirel Üniversitesi, Tıp Fakültesi, Çocuk Sağlığı ve Hastalıkları Anabilim Dalı, 2006. / Kaynakça var.

Introdução: Staphylococcus aureus é um patógeno que causa uma variedade de infecções nosocomiais e comunitárias. Bacteremia por Staphylococcus aureus meticilina resistente (MRSA) está associada com uma elevada morbidade e mortalidade. Alguns autores consideram uma maior taxa de mortalidade em bacteremia por MRSA em comparação aos observados em bacteremia causada por Staphylococcus aureus sensível a meticilina. O uso da vancomicina no tratamento de infecções por MRSA tem estado sobre crescente vigilância nos últimos anos, já que existe uma grande preocupação sobre a redução de sua eficácia no tratamento de pacientes com bacteremia por MRSA. Estudos sugerem que a vancomicina tem atividade reduzida contra infecções por MRSA quando os valores da concentração inibitória mínima (CIM) se aproximam do valor máximo considerável como susceptível. O locus (acessory gene regulator) regula a expressão de vários genes de virulência, de aderência e produção de biofilme, e pode estar envolvido com a diminuição da sensibilidade a vancomicina. O staphylococcal cassette chromosome (SCCmec) carreia o gene mecA que caracteriza o fenótipo clássico de MRSA e confere resistência aos antibióticos β-lactâmicos. Objetivos: Avaliar as CIMs dos antibióticos: vancomicina, por microdiluição em caldo, e daptomicina, linezolida, tigeciclina e quinopristina/dalfopristina e teicoplanina pela metodologia de Etest®; caracterizar o polimorfismo do locus agr e os tipos de SCCmec de isolados de MRSA de pacientes internados em um hospital, terciário e acadêmico, no sul do Brasil. Métodos: Estudo retrospectivo de coorte no qual foram avaliados todos os episódios de bacteremia causada por MRSA nos Centros de Terapia Intensiva (CTIs) durante o período de junho de 2009 a dezembro de 2011. A detecção dos grupos agr (agr tipo I, II, III e IV) e SCCmec (SCCmec I, II, III, IV e V) foi realizada a partir da técnica da reação em cadeia da polimerase (PCR). Resultados: Foram incluídos no total 21 pacientes. Os isolados de MRSA testados se apresentaram sensíveis a todos os antibióticos testados. O locus agr foi determinado em todos os isolados, sendo que onze pertencem ao grupo agr I (52,4%) e dez ao grupo agr II (27,6%). Já a caracterização dos tipos de SCCmec, não foi possível para onze isolados; para o restante, foi encontrado dois isolados SCCmec tipo I, cinco SCCmec tipo III e três SCCmec tipo IV. Conclusão: Apesar do pequeno número de pacientes e da necessidade de maiores estudos em nosso meio, nossos resultados sugerem que a vancomicina continua a ser a primeira opção de escolha para o tratamento de infecções por MRSA, como recomendado pela Infectious Diseases Society of America. No entanto, a publicação de uma série de estudos sugerindo a susceptibilidade reduzida à vancomicina, mesmo com CIMs próximas ou no ponte de corte, a terapia com vancomicina não seria recomendada a estes pacientes, sendo necessário a avaliação de um novo esquema terapêutico. / Background: Staphylococcus aureus is a versatile pathogen that cause a variety of nosocomial and community infections. Bacteremia caused by methicillin-resistant Staphylococcus aureus (MRSA) is associated with high morbidity and mortality. Some authors consider a higher rate of mortality in MRSA bacteremia compared to those observed in bacteremia caused by methicillin-sensitive Staphylococcus aureus. The use of vancomycin to treat infection due to MRSA has been under increased vigilance in recent years, since there is great concern about reducing their effectiveness in treating patients with MRSA bacteremia. Studies suggest that reduced activity against vancomycin has MRSA when the values of the minimum inhibitory concentration (MIC) approach the upper end of the range of susceptibility. The agr locus (acessory regulator gene) and regulates the expression of several virulence genes, adherence and biofilm production and can be involved in reduced sensitivity to vancomycin. The staphylococcal cassette chromosome (SCCmec) carries the mecA gene that characterizes the classic phenotype of MRSA and confers resistance to β-lactam antibiotics. Objectives: Evaluate MICs of antibiotics: vancomycin, by broth microdilution, and daptomycin, linezolid, tigecycline and quinopristina / dalfopristin and teicoplanin by Etest® methodology; characterize the polymorphism of the agr locus and SCCmec types of MRSA isolates from patients in a hospital, tertiary and academic, in southern Brazil. Methods: A retrospective cohort study which evaluated all episodes of bacteremia caused by MRSA in intensive care units (ICUs) during the period June 2009 to December 2011. The detection of agr groups (agr type I, II, III and IV) and SCCmec (SCCmec I, II, III, IV and V) were performed using the technique of polymerase chain reaction (PCR). Results: We included a total twenty one patients. The MRSA isolates tested were susceptible to all antibiotics tested. The agr locus was determined in all isolates, eleven belong to agr group I (52.4%) and ten to agr group II (27.6%). Already characterization of SCCmec types, it was not possible to eleven isolates; for the remaining two isolates found was SCCmec type I, five SCCmec type III and three SCCmec type IV. Conclusions: Despite the small number of patients and the need for further studies in this area, our results suggest that vancomycin remains the first choice option for the treatment of MRSA infections, as recommended by the Infectious Diseases Society of America. However, the publication of a series of studies suggesting reduced susceptibility to vancomycin, even with MICs near or on cut off, with vancomycin therapy would not be recommended for these patients, the evaluation of a new regimen is necessary.

Introdução: Staphylococcus aureus é um patógeno que causa uma variedade de infecções nosocomiais e comunitárias. Bacteremia por Staphylococcus aureus meticilina resistente (MRSA) está associada com uma elevada morbidade e mortalidade. Alguns autores consideram uma maior taxa de mortalidade em bacteremia por MRSA em comparação aos observados em bacteremia causada por Staphylococcus aureus sensível a meticilina. O uso da vancomicina no tratamento de infecções por MRSA tem estado sobre crescente vigilância nos últimos anos, já que existe uma grande preocupação sobre a redução de sua eficácia no tratamento de pacientes com bacteremia por MRSA. Estudos sugerem que a vancomicina tem atividade reduzida contra infecções por MRSA quando os valores da concentração inibitória mínima (CIM) se aproximam do valor máximo considerável como susceptível. O locus (acessory gene regulator) regula a expressão de vários genes de virulência, de aderência e produção de biofilme, e pode estar envolvido com a diminuição da sensibilidade a vancomicina. O staphylococcal cassette chromosome (SCCmec) carreia o gene mecA que caracteriza o fenótipo clássico de MRSA e confere resistência aos antibióticos β-lactâmicos. Objetivos: Avaliar as CIMs dos antibióticos: vancomicina, por microdiluição em caldo, e daptomicina, linezolida, tigeciclina e quinopristina/dalfopristina e teicoplanina pela metodologia de Etest®; caracterizar o polimorfismo do locus agr e os tipos de SCCmec de isolados de MRSA de pacientes internados em um hospital, terciário e acadêmico, no sul do Brasil. Métodos: Estudo retrospectivo de coorte no qual foram avaliados todos os episódios de bacteremia causada por MRSA nos Centros de Terapia Intensiva (CTIs) durante o período de junho de 2009 a dezembro de 2011. A detecção dos grupos agr (agr tipo I, II, III e IV) e SCCmec (SCCmec I, II, III, IV e V) foi realizada a partir da técnica da reação em cadeia da polimerase (PCR). Resultados: Foram incluídos no total 21 pacientes. Os isolados de MRSA testados se apresentaram sensíveis a todos os antibióticos testados. O locus agr foi determinado em todos os isolados, sendo que onze pertencem ao grupo agr I (52,4%) e dez ao grupo agr II (27,6%). Já a caracterização dos tipos de SCCmec, não foi possível para onze isolados; para o restante, foi encontrado dois isolados SCCmec tipo I, cinco SCCmec tipo III e três SCCmec tipo IV. Conclusão: Apesar do pequeno número de pacientes e da necessidade de maiores estudos em nosso meio, nossos resultados sugerem que a vancomicina continua a ser a primeira opção de escolha para o tratamento de infecções por MRSA, como recomendado pela Infectious Diseases Society of America. No entanto, a publicação de uma série de estudos sugerindo a susceptibilidade reduzida à vancomicina, mesmo com CIMs próximas ou no ponte de corte, a terapia com vancomicina não seria recomendada a estes pacientes, sendo necessário a avaliação de um novo esquema terapêutico. / Background: Staphylococcus aureus is a versatile pathogen that cause a variety of nosocomial and community infections. Bacteremia caused by methicillin-resistant Staphylococcus aureus (MRSA) is associated with high morbidity and mortality. Some authors consider a higher rate of mortality in MRSA bacteremia compared to those observed in bacteremia caused by methicillin-sensitive Staphylococcus aureus. The use of vancomycin to treat infection due to MRSA has been under increased vigilance in recent years, since there is great concern about reducing their effectiveness in treating patients with MRSA bacteremia. Studies suggest that reduced activity against vancomycin has MRSA when the values of the minimum inhibitory concentration (MIC) approach the upper end of the range of susceptibility. The agr locus (acessory regulator gene) and regulates the expression of several virulence genes, adherence and biofilm production and can be involved in reduced sensitivity to vancomycin. The staphylococcal cassette chromosome (SCCmec) carries the mecA gene that characterizes the classic phenotype of MRSA and confers resistance to β-lactam antibiotics. Objectives: Evaluate MICs of antibiotics: vancomycin, by broth microdilution, and daptomycin, linezolid, tigecycline and quinopristina / dalfopristin and teicoplanin by Etest® methodology; characterize the polymorphism of the agr locus and SCCmec types of MRSA isolates from patients in a hospital, tertiary and academic, in southern Brazil. Methods: A retrospective cohort study which evaluated all episodes of bacteremia caused by MRSA in intensive care units (ICUs) during the period June 2009 to December 2011. The detection of agr groups (agr type I, II, III and IV) and SCCmec (SCCmec I, II, III, IV and V) were performed using the technique of polymerase chain reaction (PCR). Results: We included a total twenty one patients. The MRSA isolates tested were susceptible to all antibiotics tested. The agr locus was determined in all isolates, eleven belong to agr group I (52.4%) and ten to agr group II (27.6%). Already characterization of SCCmec types, it was not possible to eleven isolates; for the remaining two isolates found was SCCmec type I, five SCCmec type III and three SCCmec type IV. Conclusions: Despite the small number of patients and the need for further studies in this area, our results suggest that vancomycin remains the first choice option for the treatment of MRSA infections, as recommended by the Infectious Diseases Society of America. However, the publication of a series of studies suggesting reduced susceptibility to vancomycin, even with MICs near or on cut off, with vancomycin therapy would not be recommended for these patients, the evaluation of a new regimen is necessary.

Submitted by Juliana da Silva Oliveira null (julianaoliveira_enf@yahoo.com.br) on 2016-09-11T21:03:04Z No. of bitstreams: 1 DISSERTACAO JULIANA OLIVEIRA pdf.pdf: 874937 bytes, checksum: e0c74af40cc92b0d03be09da8c3d52d1 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-09-12T17:21:46Z (GMT) No. of bitstreams: 1 oliveira_js_me_bot.pdf: 874937 bytes, checksum: e0c74af40cc92b0d03be09da8c3d52d1 (MD5) / Made available in DSpace on 2016-09-12T17:21:46Z (GMT). No. of bitstreams: 1 oliveira_js_me_bot.pdf: 874937 bytes, checksum: e0c74af40cc92b0d03be09da8c3d52d1 (MD5) Previous issue date: 2016-08-01 / Objetivos: Questionamentos têm sido lançados sobre a eficácia das formulações genéricas de vancomicina, empregadas com frequência nos países em desenvolvimento. No entanto, a grande disponibilidade de testes para monitorar a concentração de vancomicina no soro tornou possível ajustar as doses, a fim de melhorar os resultados. Nosso estudo teve como objetivo descrever os padrões de prescrição e monitorização de dose sérica de vancomicina genérica em um hospital brasileiro. Estávamos especialmente interessados no impacto desses parâmetros sobre o prognóstico de pacientes. Métodos: Uma coorte retrospectiva de 513 pacientes adultos que foram tratados com vancomicina em 2014 foi estudada. Desfechos de interesse foram: (a) atingir concentrações séricas mínimas sub-ótimas na primeira ocasião de monitoramento e (b) morte dentro de 30 dias da introdução vancomicina. A análise multivariada (regressão logística e de Cox) foi aplicada. Resultados: Menos de 25% dos indivíduos alcançaram concentração sérica mínima ótima (15-20 mg/L), mesmo depois de cinco testes e ajustes posológicos. No entanto, a soma dos indivíduos que apresentaram concentrações ideais e altas foi predominante em cada teste. Doença renal (OR = 4,86, IC95% = 2,05-11,53, P <0,001) e dose diária (OR para mg/kg = 1,04, IC95% = 1,01-1,07, P = 0,01) foram positivamente associada com níveis mais elevados de vancomicina. Além disso, indivíduos mais jovens eram menos propensos a apresentar baixa concentração sérica. Na análise de sobrevivência, as concentrações ideais foram associadas com melhores desfechos, mas apenas aqueles com níveis elevados apresentaram aumento significativo do risco (HR = 1,80, IC95% = 1,05-3,07, P = 0,03). Conclusão: Os resultados alertam para riscos de toxicidade com altas concentrações de vancomicina. O ajuste fino da posologia (por exemplo, com infusão contínua) pode contribuir para melhorar a segurança e eficácia. / Objectives: Concerns have been raised about generic formulations of vancomycin – especially in developing countries – but the wide availability of tests for monitoring serum vancomycin concentration made it possible to adjust doses in order to improve outcomes. We aimed at describing patterns of generic vancomycin prescription and monitoring in a Brazilian hospital and their impact on outcomes. Methods: A cohort of 513 adult patients who were treated with vancomycin in year 2014 was retrospectively studied. Outcomes of interest were achieving suboptimal serum trough concentrations in the first serum monitoring and death within 30 days of vancomycin introduction. Multivariable analysis (logistic and Cox regression was applied) Results: Less than 25% of subjects achieved optimal (15-20 mg/L) trough concentrations, even after five tests and dosing adjustments. However, the sum of subjects presenting optimal and high concentrations was predominant in each and every test. Renal disease (OR=4.86, 95%CI=2.05-11.53, P<0.001) and daily dosing (OR for mg/kg =1.04, IC95%=1.01-1.07, P=0.01) were positively associated with higher vancomycin levels. Additionally, younger subjects were less likely to present lower serum concentration. In survival analysis, optimal concentrations were associated with better outcomes, but only those with high levels presented significantly increased risk (HR=1.80, 95%CI=1.05-3.07, P=0.03). Conclusion: Our results warn about risks of toxicity with high concentrations of vancomycin. Fine adjustment of posology (e.g., with continuous infusion) may contribute to improve safety and efficacy.

Orientador: Carlos Magno Castelo Branco Fortaleza / Resumo: Objetivos: Questionamentos têm sido lançados sobre a eficácia das formulações genéricas de vancomicina, empregadas com frequência nos países em desenvolvimento. No entanto, a grande disponibilidade de testes para monitorar a concentração de vancomicina no soro tornou possível ajustar as doses, a fim de melhorar os resultados. Nosso estudo teve como objetivo descrever os padrões de prescrição e monitorização de dose sérica de vancomicina genérica em um hospital brasileiro. Estávamos especialmente interessados no impacto desses parâmetros sobre o prognóstico de pacientes. Métodos: Uma coorte retrospectiva de 513 pacientes adultos que foram tratados com vancomicina em 2014 foi estudada. Desfechos de interesse foram: (a) atingir concentrações séricas mínimas sub-ótimas na primeira ocasião de monitoramento e (b) morte dentro de 30 dias da introdução vancomicina. A análise multivariada (regressão logística e de Cox) foi aplicada. Resultados: Menos de 25% dos indivíduos alcançaram concentração sérica mínima ótima (15-20 mg/L), mesmo depois de cinco testes e ajustes posológicos. No entanto, a soma dos indivíduos que apresentaram concentrações ideais e altas foi predominante em cada teste. Doença renal (OR = 4,86, IC95% = 2,05-11,53, P <0,001) e dose diária (OR para mg/kg = 1,04, IC95% = 1,01-1,07, P = 0,01) foram positivamente associada com níveis mais elevados de vancomicina. Além disso, indivíduos mais jovens eram menos propensos a apresentar baixa concentração sérica. Na análise... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Objectives: Concerns have been raised about generic formulations of vancomycin – especially in developing countries – but the wide availability of tests for monitoring serum vancomycin concentration made it possible to adjust doses in order to improve outcomes. We aimed at describing patterns of generic vancomycin prescription and monitoring in a Brazilian hospital and their impact on outcomes. Methods: A cohort of 513 adult patients who were treated with vancomycin in year 2014 was retrospectively studied. Outcomes of interest were achieving suboptimal serum trough concentrations in the first serum monitoring and death within 30 days of vancomycin introduction. Multivariable analysis (logistic and Cox regression was applied) Results: Less than 25% of subjects achieved optimal (15-20 mg/L) trough concentrations, even after five tests and dosing adjustments. However, the sum of subjects presenting optimal and high concentrations was predominant in each and every test. Renal disease (OR=4.86, 95%CI=2.05-11.53, P<0.001) and daily dosing (OR for mg/kg =1.04, IC95%=1.01-1.07, P=0.01) were positively associated with higher vancomycin levels. Additionally, younger subjects were less likely to present lower serum concentration. In survival analysis, optimal concentrations were associated with better outcomes, but only those with high levels presented significantly increased risk (HR=1.80, 95%CI=1.05-3.07, P=0.03). Conclusion: Our results warn about risks of toxicity with high conc... (Complete abstract click electronic access below) / Mestre