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Prevalência e Susceptibilidade Antimicrobiana de Patógenos Causadores de Mastite em Rebanhos Leiteiros / Prevalence and antimicrobial susceptibility of pathogens causing mastitis in dairy herdsBeuron, Daniele Cristine 31 October 2012 (has links)
Os objetivos do presente estudo foram: a) avaliar a frequência de isolamentos de patógenos causadores de mastite em rebanhos leiteiros comerciais; b) determinar a susceptibilidade antimicrobiana de Staphylococcus spp. e Streptococcus spp. isolados de casos de mastite subclínica c) avaliar o perfil de multirresistência de Staphylococcus spp. e Streptococcus spp. d) Detectar o gene mecA em Staphylococcus spp. resistentes a oxacilina/meticilina; e) avaliar a associação entre as práticas de manejo e tratamento de mastite e a susceptibilidade antimicrobiana de Staphylococcus aureus isolados de rebanhos leiteiros. Foram selecionados para o presente estudo 13 rebanhos leiteiros a partir de um total de 60 rebanhos vinculados a um laticínio da região de Pirassununga/SP. Questionários previamente formulados foram respondidos pelos responsáveis do rebanho para avaliar a associação entre as práticas de manejo e tratamento de mastite e a susceptibilidade antimicrobiana de S. aureus. Após a seleção dos rebanhos e aplicação dos questionários, 1069 amostras de leite compostas foram coletadas durante 24 meses, em quatro períodos para realização de cultura e identificação dos patógenos, testes de susceptibilidade antimicrobiana e detecção do gene mecA. Os testes de susceptibilidade foram realizados em todos os isolados de Staphylococcus spp. e em 50% de Streptococcus spp. selecionados aleatoriamente. Os antimicrobianos testados foram: ampicilina 10 mg; clindamicina 2 µg, penicilina 1 mg; ceftiofour 30 µg; gentamicina 10 mg; sulfatrimetropin 25 µg, enrofloxacina 5 µg; sulfonamida 300 µg, tetraciclina 30 µg; oxacilina 1 mg; cefalotina 30 µg e eritromicina 5 µg. Todos os isolados de Staphylococcus spp. que apresentaram resistência a oxacilina/meticilina foram avaliados quanto à presença do gene mecA. Entre os isolados, Staphylococcus coagulase negativa foi o mais prevalente (28,6%), seguido por S. aureus (27,8%) e Corynebacterium spp. (10,9%). A susceptibilidade antimicrobiana dos isolados de S. aureus foi de 95,23% (eritromicina), 93,33% (cefalotina) e 65,71% (ampicilina). A susceptibilidade antimicrobiana dos isolados de Staphylococcus coagulase negativa (SCN) foi de 93,33% (cefalotina), 89,91% (eritromicina) e 62,03% (ceftiofur). Entre os isolados de Staphylococcus coagulase positiva (SCP), a susceptibilidade antimicrobiana foi de 93,33% (eritromicina), 91,11% (clindamicina e sulfonamida). A susceptibilidade antimicrobiana dos isolados de Streptococcus agalactiae foi de 38,46% (ampicilina) e 50% (sulfatrimetropin) e os isolados de S. dysgalactiae apresentaram susceptibilidade à tetraciclina de 19,44% e a clindamicina de 47,22%. A multirresistência foi maior entre os isolados de SCN (20,3%) e S.aureus (15,7%). Não foi detectado o gene mecA em nenhum dos isolados de Staphylococcus spp. Houve associação entre as variáveis para os seguintes antimicrobianos: a) tratamento de mastite clínica: ampicilina (P = 0,0055), ceftiofur (P = 0,0481), sulfatrimetropin (P= 0,0293), sulfonamida (P = 0,0043) e tetraciclina (P = 0,0058); e envio de amostras para cultura e antibiograma: ampicilina (P=0,0032), tetraciclina (P=<0,0001). Os principais fatores de risco para susceptibilidade antimicrobiana de S. aureus foram o não envio de amostras para cultura e antibiograma para tetraciclina (OR=6.012), penicilina (OR=4.687), eritromicina (OR=3.059) e ampicilina (OR=2.571), tratamento de mastite clínica para ampicilina (OR=2.178), ceftiofur (OR=1.956), gentamicina (OR=1.668), oxacilina (OR= 1.132) e penicilina (OR= 1.261) e tratamento de vaca seca para enrofloxacina (OR=2.111) e tetraciclina (OR=2.075). Os microrganismos mais frequentemente isolados foram Staphylococcus coagulase negativa e S. aureus. Os testes de susceptibilidade realizados para as espécies de Staphylococcus spp. e Streptococcus spp. apresentaram alta susceptibilidade para a maioria dos antimicrobianos testados. Com exceção de Streptococcus agalactiae para ampicilina e sulfatrimetropin e os isolados de S. dysgalactiae para tetraciclina e clindamicina. A maioria dos Staphylococcus spp. e Streptococcus spp. não apresentaram perfil de multirresistência. Nenhum dos isolados de Staphylococcus spp. fenotipicamente resistentes a oxacilina/meticilina apresentaram o gene mecA. O maior fator de risco associado à susceptibilidade de S. aureus foi em relação à tetraciclina, penicilina, eritromicina e ampicilina para o não envio de amostras para cultura e antibiograma. Dois fatores de risco importantes identificados foram relacionados à ampicilina, ceftiofur, gentamicina, oxacilina e penicilina para o tratamento de mastite clínica e à enrofloxacina e tetraciclina para o tratamento de vaca seca. / The aims of this study were: a) to evaluate the frequency of mastitis pathogens in commercial dairy herds, b) to determine the antimicrobial susceptibility of Staphylococcus spp. and Streptococcus spp. isolated from subclinical mastitis c) to evaluate the profile of multidrug resistance of Staphylococcus spp. and Streptococcus spp. d) to detect the mecA gene in Staphylococcus spp. resistant to oxacillin / methicillin, e) to evaluate the association between management practices and treatment of mastitis, and antimicrobial susceptibility of Staphylococcus aureus isolates from dairy herds. Thirteen dairy herds were selected from a total of 60 dairy farms in the region of Pirassununga / SP. Questionnaires formulated previously were answered by dairy farmers to evaluate the association between mastitis treatment practices and antimicrobial susceptibility. A total of 1,069 composite samples of milk from all herds were collected for culture and identification of pathogens, susceptibility testing and mecA gene detection, over 24 months in four periods. The susceptibility tests were performed in all isolates of Staphylococcus spp. and in 50% of Streptococcus spp. randomly selected. The antimicrobials tested were ampicillin 10mg; 2µg clindamycin, penicillin 1mg; ceftiofour 30µg; gentamicin 10mg; sulfatrimetropin 25µg, 5µg enrofloxacin; 300µg sulfonamide, tetracycline 30µg; oxacillin 1mg; 30µg cephalothin and erythromycin 5µg. All Staphylococcus spp. that were resistant to oxacillin/methicillin in the susceptibility tests were investigated for the presence of mecA gene. Among the isolated bacteria, CNS was the most prevalent (28.6%), followed by S. aureus (27.8%) and Corynebacterium spp. (10.9%). The antimicrobial susceptibility of isolates of S. aureus was 95.23% (erythromycin), 93.33% (cephalothin) and 65.71% (ampicillin). The antimicrobial susceptibility of isolates of coagulase-negative Staphylococcus (CNS) was 93.33% (cephalothin), 89.91% (erythromycin) and 62.03% (ceftiofur). Among strains of coagulase positive Staphylococcus (CPS), the antimicrobial susceptibility was 93.33% (erythromycin), 91.11% (clindamycin and sulfonamide). The antimicrobial susceptibility of the strains of Streptococcus agalactiae was 38.46% (ampicillin) and 50% (sulfatrimetropin) and isolates of S. dysgalactiae were susceptible to tetracycline and clindamycin (19.44% to 47.22%). The multidrug resistance was higher among isolates of CNS (20.3%) and Staphylococcus aureus (15.7%). The mecA gene was not detected in any of Staphylococcus spp isolates. There was an association between variables for the following antimicrobials: a) treatment of clinical mastitis: ampicillin (P = 0.0055), ceftiofur (P = 0.0481), sulfatrimetropin (P = 0.0293), sulfonamide (P = 0.0043) and tetracycline (P = 0.0058); and sending samples for culture and antibiogram: ampicillin (P = 0.0032), tetracycline (P = <0.0001). Major risk factors for antimicrobial susceptibility of S. aureus were not submitting samples for culture and antibiogram for tetracycline (OR = 6.012), penicillin (OR = 4.687), erythromycin (OR = 3.059) and ampicillin (OR = 2.571), treatment of clinical mastitis: ampicillin (OR = 2.178), ceftiofur (OR = 1.956), gentamicin (OR = 1.668), oxacillin (OR = 1.132) and penicillin (OR = 1.261); and dry cow therapy: enrofloxacin (OR = 2.111) and tetracycline (OR = 2.075). The most frequent organisms isolated were coagulase negative Staphylococcus and S. aureus. The susceptibility tests performed for the species of Staphylococcus spp. and Streptococcus spp. showed high susceptibility to most antimicrobials tested. With the exception of Streptococcus agalactiae to ampicillin and sulfatrimetropin and isolates of S. dysgalactiae to tetracycline and clindamycin. Most Staphylococcus spp. and Streptococcus spp. did not show multidrug resistance profile. None of Staphylococcus spp. phenotypically resistant to oxacillin / methicillin showed the mecA gene. The major risk factor associated with susceptibility of S. aureus to tetracycline, penicillin, erythromycin and ampicillin was not sending samples for culture and sensitivity. Two important risk factors have been identified related to ampicillin, ceftiofur, gentamicin, penicillin and oxacillin for treatment of clinical mastitis and enrofloxacin and tetracycline for the treatment of dry cow dry cow therapy.
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Avaliação da resistência de Mycobacterium tuberculosis a drogas através de testes fenotípicos, moleculares comerciais e do sequenciamento genômico total / Evaluation of Mycobacterium tuberculosis resistance to drugs through phenotypic, commercial molecular tests and whole genome sequencingFeliciano, Cinara Silva 23 February 2018 (has links)
A tuberculose (TB) embora passível de tratamento efetivo, ainda é um grave problema de saúde pública em diversos países, inclusive no Brasil. Nas últimas décadas houve progressos consistentes no controle da doença, porém o avanço da resistência bacilar ainda é um desafio a ser superado, já que os mecanismos da resistência são bastante complexos e não totalmente conhecidos, o que dificulta o desenvolvimento de testes de sensibilidade com elevada acurácia. O objetivo deste trabalho foi caracterizar as mutações gênicas de cepas de Mycobacterium tuberculosis de pacientes do Brasil e de Moçambique com doença resistente a drogas através do sequenciamento genômico total, além de descrever padrões de mutações obtidos por testes moleculares comerciais e comparar estes dados com resultados de testes fenotípicos. Estudo descritivo e transversal que incluiu 30 isolados (17 do Brasil e 13 de Moçambique), submetidos aos testes moleculares comerciais Genotype MTBDRplus®, Genotype MTBDRsl®, Xpert MTB/RIF® e teste fenotípico BACTEC MGIT 960 SIRE®. Todos os isolados também foram avaliados pelo sequenciamento genômico realizado pelo Illumina MiSeq Sequencing System® e submetidos a análise de mutações que conferem resistência às drogas contra TB utilizando o TB profiler online tool. A sensibilidade e especificidade do sequenciamento genômico para detecção de resistência a rifampicina foi de 87,5% e 92,3%, respectivamente. Além disso, o sequenciamento detectou a mutação (Val170Phe) no gene rpoB em dois isolados de M. tuberculosis de Moçambique. Esta mutação não é detectada pelos testes genotípicos comerciais. A sensibilidade do sequenciamento para a isoniazida foi de 95,6% e a especificidade de 100%. Para a estreptomicina, a sensibilidade foi de 85,7% e a especificidade de 93,3%. Para o etambutol, observamos sensibilidade de 100% e especificidade de 77,2%. As mutações mais frequentes associadas à resistência à rifampicina foram a Ser450Leu e a His445Tyr no gene rpoB. Em relação à isoniazida, predominou a mutação Ser315Thr no gene katG. O sequenciamento genômico, dado seu alto poder discriminatório, tem grande potencial de fornecer informações mais acuradas sobre mecanismo gênicos da resistência bacilar, possibilitando futuramente o aprimoramento de testes diagnósticos mais precisos. / Although there is an effective treatment for tuberculosis (TB), it is still a serious public health problem in several countries, including Brazil. In the last decades, there has been consistent progress in disease control, but the increasing number of disease caused by resistant strains is still a challenge to be overcome, since the mechanisms of resistance are quite complex and not fully known, which difficult the development of susceptibility tests with high accuracy. The aim of this work was to characterize gene mutations of Mycobacterium tuberculosis strains from Brazilian and Mozambican patients with drug-resistant disease through whole genome sequencing, as well as to describe patterns of mutations obtained by commercial molecular tests and to compare these data with results of phenotypic susceptibility tests. It was a cross-sectional study that included 30 isolates (17 from Brazil and 13 from Mozambique). Commercial molecular tests Genotype MTBDRplus(TM), Genotype MTBDRsl(TM), Xpert MTB / RIF(TM) and BACTEC MGIT 960 SIRE(TM) phenotypic test were performed for all isolates. All of them were also evaluated by whole genome sequencing performed by the Illumina MiSeq Sequencing System(TM) and submitted to analysis of mutations that confer drug resistance against TB using the TB profiler online tool. The sensitivity and specificity of whole genome sequencing for detection rifampicin resistance was 87.5% and 92.3%, respectively. Also, whole genome sequencing detected the mutation (Val170Phe) in the rpoB gene in two isolates of M. tuberculosis from Mozambique. This mutation is not detected by commercial genotypic tests. The sensitivity of the whole genome sequencing for isoniazid was 95.6%, and the specificity was 100%. For streptomycin, the sensitivity was 85.7%, and the specificity was 93.3%. For ethambutol, we observed a sensitivity of 100% and specificity of 77.2%. The most frequent mutations associated with rifampicin resistance were rpoB Ser450Leu and His445Tyr. About isoniazid, the katG Ser315Thr mutation was the most frequent. Whole genome sequencing, given its high discriminatory power, has great potential to provide more accurate information about the gene mechanisms of bacilli resistance, making possible the improvement of more accurate diagnostic tests in the future.
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Caracterização molecular e fenotípica de amostras bacterianas pertencentes ao complexo Acinetobacter calcoaceticus-Acinetobacter baumannii / Molecular and phenotypic characterization of Acinetobacter calcoaceticus-Acinetobacter baumannii isolatesTakagi, Elizabeth Harummyy 31 August 2011 (has links)
Nos últimos 30 anos, Acinetobacter tornou-se um dos patógenos de maior preocupação clínica pela falta de terapias eficazes em virtude do fenótipo de multirresistência frequentemente apresentado. Dentre as espécies do gênero Acinetobacter, A. baumannii, A. genoespécie 3 e A. genoespécie 13TU são as mais comumente encontradas a partir de amostras biológicas. Estas espécies ao lado de A. calcoaceticus constituem o complexo A. calcoaceticus-A. baumannii (ACB). Este estudo propõe um esquema composto de duas PCRs para a identificação das espécies de interesse médico que fazem parte do complexo ACB. O método é simples, rápido e, além de identificar as espécies, permite pesquisar a presença de genes de resistência. Foram identificadas 515 amostras do complexo ACB, isoladas de pacientes no período de janeiro de 2005 a dezembro de 2010. A identificação das espécies do complexo ACB foi realizada por esquema composto de duas reações de PCR. Foram avaliados os perfis de sensibilidade por disco difusão e a pesquisa da presença dos genes blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, blaOXA-58-like, blaIMP, blaVIM, blaSIM, blaSPM e blaGIM foi realizada por PCR utilizando-se iniciadores específicos. No grupo de amostras estudas, 82,5% são A. baumannii (425), 11,5% A. genoespécie 13TU (59) e 6,0% A. genoespécie 3 (30), sendo A. baumannii mais isolado em pacientes internados em UTIs (p=0,0407) e A. genoespécie 13TU mais isolado em pacientes de outros ambientes hospitalares (p=0,0204). A. baumannii apresentou menor sensibilidade a todos os antimicrobianos quando comparado com A. genoespécie 13TU e A. genoespécie. 3 (p<0,05). Foi possível observar ao longo do período estudado o aumento significativo da resistência aos carbapenêmicos e da sensibilidade a gentamicina por A. baumannii entre os isolados de pacientes de UTIs (p<0.05). Nenhum dos genes codificadores para metalo-lactamases foi detectado nas amostras estudadas Dentre os cepas resistentes aos carbapenêmicos (176) o gene blaOXA-23 foi detectado em 81,25% e uma amostra de A. baumannii apresentou o gene codificador para OXA-72. A tipagem molecular foi realizada por RAPD e para os isolados resistentes aos carbapenêmicos também por PFGE. Resultados obtidos por RAPD revelaram menor diversidade entre os isolados de pacientes internados em UTIs. O dendrograma obtido utilizando-se PFGE separou dois clones cujos componentes eram resistentes aos carbapenêmicos, no entanto não apresentavam o gene blaOXA-23-like. A produção de acil-homoserina lactona, autoindutor-2 e autoindutor-3 de três amostras de cada espécie clínica do complexo ACB foi pesquisada utilizando-se bioensaios. Apenas Autoindutor 3 foi detectado por bioensaio e em menor quantidade no meio précondicionados obtido a partir de A. genoespécie 3 quando comparado com A. genoespécie 13TU e A. baumannii (p<0.05). Três cepas de cada espécie clínica do complexo ACB foi avaliada quanto a capacidade de adesão em monocamada de células Hep-2, MRC-5 e NCI-H292, sendo essa última a que revelou diferenças entre as espécies clínicas do complexo ACB. A. baumannii apresentou adesão difusa, A. genoespécie 13 TU adesão com formação de agrupamentos e A. genoespécie 3 não aderiu. Esse mesmo ensaio foi realizado na presença de propanolol e notou-se a diminuição de células aderidas por campo observado. Dez cepas de cada espécie clínica do complexo ACB foram pesquisadas quanto a produção de biofilme por ensaio colorimétrico utilizando cristal violeta e foi possível notar a produção significativa de biofilme por A. baumannii, quando comparado com A. genoespécie 3 (p<0.05). Esse mesmo ensaio na presença de de fentolamina, mostrou a diminuição significativa na produção do biofilme por A. baumannii. A interferência no ensaio de adesão bacteriana e biofilme, na presença de fentolamina ou propanolol, sugerem o envolvimento do autoindutor-3 na regulação desses mecanismos de virulência. / The genus Acinetobacter has emerged as one of the most troublesome pathogens for health care institutions globally. Its clinical significance, especially over the last 15 years, has been driven by its remarkable ability to up regulate or acquire resistance determinants, making it one of the organisms threatening the current antibiotic era. A. baumannii, A. 3 and A. 13TU are the most commonly species found from biological samples. These species beside A. calcoaceticus are very closely related and difficult to distinguish from each other by phenotypic properties. Therefore, it has been proposed to refer to these species as the A.calcoaceticus-A. baumannii complex(ACB). In the period from 2005 to 2009, the most frequent bacterial isolates among the nosocomial infection at the HU-USP was ACB (18%). Due to the frequency with which species are involved in ACB outbreaks of infection in the HU-USP and the emergency clinic because of expression of the phenotype of resistance to several classes of antibiotics, this study aimed to identify and characterize the species of complex ACB by molecular methods, to study their mechanisms of resistance and to characterize the different clones from patients admitted to different hospital areas. Furthermore, the ability to characterize biofilm formation, adhesion to different cell lines as well as the mechanisms of cell-cell communication were analyzed. From the ACB complex, 515 samples were identified, isolated from patients from January 2005 to December 2010. The identification of clinical species of the ACB was performed by molecular methods that were developed and validated for identification of Acinetobacter sp. include two reactions of PCR. The profiles of sensibility were evaluated by disc diffusion and the detection of the presence of genes blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, blaOXA-58-like, blaIMP, blaVIM, blaSIM, blaGIM, and blaSPM were performed using specific primers. Molecular typing was performed by RAPD and isolates resistant to carbapenems also by PFGE. The production of autoinducers of three clinical species complex was sought using bioassays with sensor strains. The ability adhesion was evaluated in monolayer of Hep-2 cells, MRC-5 and NCI-H292E. Ten clinical strains of each species of ACB complex were screened for the production of biofilms by colorimetric assay using crystal violet. Among all the strains studied, 82.5% were A. baumannii (425), 11.5% A.13TU (59) and 6.0% A. 3 (30). A. baumannii strains were more isolated from intensive care unit (ICU) patients (p = 0.0407) and A. 13TU from other patients in different hospital settings (p = 0.0204). A. baumannii showed less sensitivity to all drugs when compared with A. 13TU and A.3 (p <0.05). It was possible to observe during the study period a significant increase in carbapenem resistance and sensitivity to gentamicin by A. baumannii isolates from patients in ICUs (p <0.05). No genes coding for metallo-lactamase was detected in the samples studied. blaOXA-23 gene was detected in 81.25% among the 176 strains resistant to carbapenems. Results obtained by RAPD revealed less diversity among isolates from ICU patients compared to isolates from patients from other hospitals. The dendrogram obtained by PFGE showed less diversity than RAPD It was unable to detect homoserine lactone and autoinducer-2 by bioassay. The survey was positive of autoinducer-3 observed differences in yield among clinical species, smaller amount produced by strains of A. 3 when compared with A. 13TU and A. baumannii (p <0.05). Among the cells studied in adhesion testing, line NCI-H292 showed the greatest power discrimination between adhesion pattern observed and species of the ACB. A. baumannii showed diffuse adherence, A. 13 TU strains showed adhesion clustering and A. 3 did not adhere. This experiment was repeated in the presence of 100 µM of propranolol and it was noted a decrease in cell A. 13TU and A. baumannii adhered per field observed. The biofilm assay showed significantly higher production of biofilms by A.baumannii compared with A. 3 (p <0.05). When the test was conducted in the presence of phentolamine at 100µM, it was observed a significant decrease in the biofilm productions by A. baumannii, which revealing the involvement of the autoinducer-3 in biofilm production. The data obtained suggest that the proposed method of identification is a method for identification of species of medical interest belonging to the ACB complex which could be used in a routine laboratory. The method is simple, fast and beside the identification species, provides data about the resistance genes. Moreover, it revealed that the isolates of A. baumannii are more resistant and OXAbla genes, that was restricted to the ACB complex studied in this work. A. baumannii has also increased capacity for adhesion and biofilm formation, which regulates the expression of the phenotype may be linked to the production of autoinducers-3.
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Efeito inibitÃrio in vitro de ciprofloxacina isolada e em combinaÃÃo com antifÃngicos frente a Coccidioides posadasii e Histoplasma capsulatum var. capsulatum. / In vitro inhibitory effect of ciprofloxacin alone and in combination with antifungal drugs against Coccidioides posadasii and Histoplasma capsulatum var. capsulatumÃrica Pacheco Caetano 10 December 2010 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A coccidioidomicose e a histoplasmose sÃo micoses sistÃmicas que acometem o homem e animais, causadas por espÃcies de fungos dimÃrficos, com Ãnfase para Coccidioides posadasii e Histoplasma capsulatum var. capsulatum, respectivamente. SÃo consideradas doenÃas profundas importantes, podendo culminar em diversas complicaÃÃes secundÃrias. Nos Ãltimos anos, a melhoria dos mÃtodos de diagnÃstico micolÃgico e o aumento da ocorrÃncia de doenÃas imunossupressoras causaram grande impacto na incidÃncia das micoses profundas e oportunistas no mundo. Apesar da existÃncia de terapias eficazes com antifÃngicos contra a coccidioidomicose e a histoplasmose, a busca por novas drogas para o tratamento destas doenÃas se faz necessÃria. Ciprofloxacina à uma droga antibacteriana clÃssica do grupo das fluoroquinolonas, que inibe a atividade catalÃtica da DNA girase e topoisomerase IV, essenciais na replicaÃÃo e transcriÃÃo do DNA bacteriano. Estudos verificaram que ciprofloxacina pode atuar na DNA girase dos fungos. Assim, o presente estudo visou avaliar o efeito inibitÃrio in vitro de ciprofloxacina (CIP) isolada e em combinaÃÃo com os antifÃngicos anfotericina B (AMB), itraconazol (ITC), voriconazol (VRC) e caspofungina (CAS) frente à C. posadasii e Histoplasma capsulatum var. capsulatum. Foram utilizados 16 cepas de C. posadasii na fase filamentosa, 16 cepas de H. capsulatum var. capsulatum na fase filamentosa e 9 cepas de H. capsulatum var. capsulatum na fase leveduriforme. O estudo foi conduzido em ensaio de macrodiluiÃÃo e microdiluiÃÃo em caldo, descritos nos documentos M-38A e M-27A2, padronizados pelo Clinical Laboratory Standards Institute (CLSI), sendo utilizados para C. posadasii e Histoplasma capsulatum var. capsulatum, respectivamente. A interaÃÃo das drogas foi analisada atravÃs do cÃlculo do Ãndice da ConcentraÃÃo InibitÃria FracionÃria (FICI), definido como a soma das relaÃÃes entre a concentraÃÃo inibitÃria mÃnima (CIM) de cada droga em combinaÃÃo e a CIM da mesma droga isolada, considerando os valores menores ou iguais a 0,5 indicativos de sinergismo. Com relaÃÃo Ãs cepas de C. posadasii, foram observadas interaÃÃes sinÃrgicas em todas as combinaÃÃes, com destaque para as associaÃÃes de CIP (3,125≤CIM≤12,5 ug mL-1) com ITC (0,0078≤CIM≤0,125 ug mL-1) (n=13/16), CIP (3,125≤CIM≤12,5 ug mL-1) com VRC (0,0078≤CIM≤0,0312 ug mL-1) (n=13/16) e CIP (3,125≤CIM≤12,5 ug mL-1) com CAS (2≤CIM≤8 ug mL-1) (n=14/16). Para as cepas de H. capsulatum na fase filamentosa, tambÃm foram observadas interaÃÃes sinÃrgicas em todas as combinaÃÃes, com destaque para as associaÃÃes de CIP (3,906≤CIM≤62,5 ug mL-1) com ITC (0,00006≤CIM≤0,0078 ug mL-1) (n=14/16) e CIP (31,25≤CIM≤125 ug mL-1) com VRC (0,0156≤CIM≤0,125 ug mL-1) (n=16/16). No tocante Ãs cepas de H. capsulatum na fase leveduriforme, foram observadas poucas interaÃÃes sinÃrgicas nas combinaÃÃes de drogas testadas. Nenhuma das associaÃÃes de drogas testadas apresentou antagonismo. Os dados obtidos apontam uma nova alternativa para o tratamento da coccidioidomicose e da histoplasmose, sendo necessÃrios novos estudos que visem investigar os mecanismos de aÃÃo dessas combinaÃÃes de drogas no metabolismo celular fÃngico, bem como o delineamento de experimentos in vivo para confirmar a significÃncia desses achados. / Coccidioidomycosis and histoplasmosis are systemic mycoses that occur in humans and other animals and are caused by the dimorphic fungi Coccidioides posadasii and Histoplasma capsulatum var. capsulatum, respectively. They are considered important deep mycoses that can lead to several secondary complications. In the past years, the improvement of the techniques applied in mycological diagnosis and the increase in the occurrence of immunocompromising diseases have caused a great impact in the incidence of deep and opportunistic mycoses in the world. In spite of the existence of effective antifungal therapy against coccidioidomycosis and histoplasmosis, the pursue of new drugs to treat theses diseases is necessary. Ciprofloxacin is a classic antibacterial drug that belongs to the group of fluoroquinolones, which inhibit the catalytic activity of DNA gyrase and topoisomerase IV, which are essential in bacterial DNA replication and transcription. Some studies have shown that ciprofloxacin can act on fungal DNA gyrase. Thus, the present study aimed at evaluating the in vitro inhibitory effect of ciprofloxacin (CIP), when associated with amphotericin B (AMB), itraconazole (ITC), voriconazole (VRC) or caspofungina (CAS), on C. posadasii and H. capsulatum var. capsulatum. Sixteen strains of C. posadasii in the filamentous phase and 16 and 9 strains of H. capsulatum in the filamentous and yeast-like phase, respectively, were used. Broth macrodilution and microdilution assays were performed, as described in the documents M38-A and M27-A2, respectively, of the Clinical Laboratory Standards Institute (CLSI). Drug interaction was analyzed by calculating the fractional inhibitory concentration index (FICI), which is defined as the sum of the ratios between the minimal inhibitory concentration (MIC) of each combined drug and the MIC of the same drug isolatedly. Values of FICI smaller or equal to 0.5 indicate the occurrence of synergy. Concerning the isolates of C. posadasii, synergistic interactions were observed for all combinations, especially for the associations of CIP (3.125≤CIM≤12.5 ug mL-1) with ITC (0.0078≤CIM≤0.125 ug mL-1) (n=13/16), CIP (3.125≤CIM≤12.5 ug mL-1) with VRC (0.0078≤CIM≤0.0312 ug mL-1) (n=13/16) and CIP (3.125≤CIM≤12.5 ug mL-1) with CAS (2≤CIM≤8 ug mL-1) (n=14/16). For the isolates of H. capsulatum in the filamentous phase synergistic interactions were also observed for all combinations, with emphasis to the associations of CIP (3.906≤CIM≤62.5 ug mL-1) with ITC (0.00006≤CIM≤0.0078 ug mL-1) (n=14/16) and CIP (31.25≤CIM≤125 ug mL-1) with VRC (0.0156≤CIM≤0.125 ug mL-1) (n=16/16). For H. capsulatum in yeast-like phase, few synergistic interactions were observed for the tested drug combinations. None of the tested combinations presented antagonism. The obtained data may point at a new alternative for the treatment of coccidioidomycosis and histoplasmosis. Thus, it is necessary to investigate the mechanisms of action of these drug combinations on the fungal cellular metabolism and to perform in vivo experiments to confirm the relevance of these findings.
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Molecular epidemiology and molecular mechanisms of antimicrobial resistance in <i>Neisseria gonorrhoeae</i> in China : implications for disease controlLiao, Mingmin 22 June 2011
Gonorrhea, caused by the human pathogen Neisseria gonorrhoeae, is a severe public health problem worldwide with more than 82 million new infections each year. N. gonorrhoeae is transmitted by sexual contact and primarily causes urogenital mucosal infections in men and women. Left untreated, this infection may cause severe complications, especially in females. Eye infections of the newborn can occur. Gonorrhea infections enhance HIV transmission. The highly prevalent antibiotic resistance and the emergence of new drug resistances render treatment of the infections increasingly difficult. Close monitoring of antimicrobial susceptibility of this pathogen is crucial, and enhanced knowledge of molecular mechanisms of gonococcal antimicrobial resistance is urgently needed. There are no vaccines available against N. gonorrhoeae. Control of gonorrhea relies on comprehensive strategies which can be better formulated by understanding, at molecular levels, how N. gonorrhoeae is transmitted in communities.
My research aimed to illustrate the severe burden of antimicrobial resistance in N. gonorrhoeae temporally and geographically in China and to reveal the molecular mechanisms of antibiotic resistance particularly the development of reduced susceptibility to ceftriaxone in N. gonorrhoeae isolates. To determine specific strain distributions, N. gonorrhoeae isolates were characterized using molecular typing methods such as a modified porB-based typing scheme and the N. gonorrhoeae Multi-Antigen Typing (NG-MAST) method, compared to traditional epidemiological approaches. The ultimate goal was to provide information for better formulating disease control strategies for gonorrhea.
In this research, male patients with gonorrhea and their sex partners were recruited in Shanghai (2005 and 2008) and in Urumchi (2007-2008), China. Epidemiological information pertaining to sexual contacts was collected. N. gonorrhoeae isolates were investigated for their antimicrobial susceptibility. Molecular mechanisms of antimicrobial resistance were explored by analysis of potential resistant determinants (gyrA, parC, porB, mtrR, ponA and penA). The molecular data were combined with bioinformatic analysis and traditional epidemiological data.
High percentages of N. gonorrhoeae isolates (11% - 19% in Shanghai, 4.5% in Urumchi) exhibited reduced susceptibility to ceftriaxone (MICs = 0.125-0.25 mg/L), the first line drug recommended for the treatment of gonorrhea in China. The majority of isolates (>98%) were susceptible to spectinomycin, an alternative regimen for gonorrhea treatment; however, the proportion of isolates having intermediate levels of susceptibility increased from 1.9% in 2005 to 9.9% in 2008. The majority of isolates tested were resistant to penicillin (80% - 93%), tetracycline (56% - 65%) and ciprofloxacin (98% - 100%). Plasmid-mediated resistance in N. gonorrhoeae isolates were highly prevalent (51% - 79%) in Shanghai and Urumchi.
Analysis of 60 clinical isolates revealed that reduced susceptibility to ceftriaxone is mediated by porB1b allele and is associated with specific mutations in penicillin binding protein 2 and in the DNA binding and dimerization domains of MtrR. Penicillin binding protein 1 is not involved in reduced susceptibility to ceftriaxone. Although mutation patterns in quinolone resistant determinant regions (QRDRs) varied, the majority of ciprofloxacin resistant isolates had double mutations in GyrA (S91F and D95G/A/N) and most isolates also carried a S87R/N mutation in ParC. The presence of mutations in the QRDR of ParC is correlated with elevated ciprofloxacin MICs.
A modified porB-based molecular typing scheme was developed and involved ~82% of the DNA sequence of gonococcal porB. This typing method proved to have high discriminatory ability (index of discrimination = 0.93 0.96), and was cost effective and easy to perform as compared to the NG-MAST analysis. Using the modified porB-based typing method, N. gonorrhoeae isolates were reliably differentiated, and transmission clusters were identified. Molecular epidemiology using the porB-based method confirmed direct sexual connections and identified sexual networks otherwise unrevealed by the patient self-reporting or traditional case-tracing methods.
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Molecular epidemiology and molecular mechanisms of antimicrobial resistance in <i>Neisseria gonorrhoeae</i> in China : implications for disease controlLiao, Mingmin 22 June 2011 (has links)
Gonorrhea, caused by the human pathogen Neisseria gonorrhoeae, is a severe public health problem worldwide with more than 82 million new infections each year. N. gonorrhoeae is transmitted by sexual contact and primarily causes urogenital mucosal infections in men and women. Left untreated, this infection may cause severe complications, especially in females. Eye infections of the newborn can occur. Gonorrhea infections enhance HIV transmission. The highly prevalent antibiotic resistance and the emergence of new drug resistances render treatment of the infections increasingly difficult. Close monitoring of antimicrobial susceptibility of this pathogen is crucial, and enhanced knowledge of molecular mechanisms of gonococcal antimicrobial resistance is urgently needed. There are no vaccines available against N. gonorrhoeae. Control of gonorrhea relies on comprehensive strategies which can be better formulated by understanding, at molecular levels, how N. gonorrhoeae is transmitted in communities.
My research aimed to illustrate the severe burden of antimicrobial resistance in N. gonorrhoeae temporally and geographically in China and to reveal the molecular mechanisms of antibiotic resistance particularly the development of reduced susceptibility to ceftriaxone in N. gonorrhoeae isolates. To determine specific strain distributions, N. gonorrhoeae isolates were characterized using molecular typing methods such as a modified porB-based typing scheme and the N. gonorrhoeae Multi-Antigen Typing (NG-MAST) method, compared to traditional epidemiological approaches. The ultimate goal was to provide information for better formulating disease control strategies for gonorrhea.
In this research, male patients with gonorrhea and their sex partners were recruited in Shanghai (2005 and 2008) and in Urumchi (2007-2008), China. Epidemiological information pertaining to sexual contacts was collected. N. gonorrhoeae isolates were investigated for their antimicrobial susceptibility. Molecular mechanisms of antimicrobial resistance were explored by analysis of potential resistant determinants (gyrA, parC, porB, mtrR, ponA and penA). The molecular data were combined with bioinformatic analysis and traditional epidemiological data.
High percentages of N. gonorrhoeae isolates (11% - 19% in Shanghai, 4.5% in Urumchi) exhibited reduced susceptibility to ceftriaxone (MICs = 0.125-0.25 mg/L), the first line drug recommended for the treatment of gonorrhea in China. The majority of isolates (>98%) were susceptible to spectinomycin, an alternative regimen for gonorrhea treatment; however, the proportion of isolates having intermediate levels of susceptibility increased from 1.9% in 2005 to 9.9% in 2008. The majority of isolates tested were resistant to penicillin (80% - 93%), tetracycline (56% - 65%) and ciprofloxacin (98% - 100%). Plasmid-mediated resistance in N. gonorrhoeae isolates were highly prevalent (51% - 79%) in Shanghai and Urumchi.
Analysis of 60 clinical isolates revealed that reduced susceptibility to ceftriaxone is mediated by porB1b allele and is associated with specific mutations in penicillin binding protein 2 and in the DNA binding and dimerization domains of MtrR. Penicillin binding protein 1 is not involved in reduced susceptibility to ceftriaxone. Although mutation patterns in quinolone resistant determinant regions (QRDRs) varied, the majority of ciprofloxacin resistant isolates had double mutations in GyrA (S91F and D95G/A/N) and most isolates also carried a S87R/N mutation in ParC. The presence of mutations in the QRDR of ParC is correlated with elevated ciprofloxacin MICs.
A modified porB-based molecular typing scheme was developed and involved ~82% of the DNA sequence of gonococcal porB. This typing method proved to have high discriminatory ability (index of discrimination = 0.93 0.96), and was cost effective and easy to perform as compared to the NG-MAST analysis. Using the modified porB-based typing method, N. gonorrhoeae isolates were reliably differentiated, and transmission clusters were identified. Molecular epidemiology using the porB-based method confirmed direct sexual connections and identified sexual networks otherwise unrevealed by the patient self-reporting or traditional case-tracing methods.
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Avaliação da suscetibilidade antimicrobiana e do perfil de macrorrestrição do DNA de isolados humanos de Salmonella serovar Typhimurium fagotipo 193, no período de 1970 a 2008 / Evaluation of antimicrobial susceptibility and macrorestriction DNA of human isolates of Salmonella serovar Typhimurium phage type 193 in the period 1970 to 2008Eliane Moura Falavina dos Reis 09 June 2011 (has links)
Para analisar cepas de Salmonella ser. Typhimurium isoladas de processos entéricos e extraintestinais humanos ocorridos no período de 1970 a 2008 de diferentes regiões do país foram selecionadas, com base nos registros contidos no banco de dados do Laboratório de Enterobactérias do IOC/FIOCRUZ, RJ, amostras do fagotipo prevalente 193, visando precipuamente o reconhecimento de clones epidêmicos. Foram selecionadas 553 cepas de Salmonella ser. Typhimurium fagotipo 193 representadas por 91, 65, 70 e 327 amostras referentes as décadas de 70, 80, 90 e ao período de 2000 a 2008, respectivamente. Na análise global da sensibilidade destas cepas, 52% apresentaram um ou mais marcadores de resistência a antibióticos incluídos no perfil ACSSuT. Este perfil de resistência completo foi verificado em 20,9% dos isolados, sendo os 21,9% restantes, sensíveis a todas as drogas testadas, especialmente no período de 2000 a 2008, representadas por 121 amostras (37,0%) em relação as 327 culturas dessa época. O maior percentual de resistência foi observado nas amostras da década de 70 (99%) sendo o perfil ACSSuT detectado em 35,2% dos isolados, ressaltando-se que todas as amostras foram isoladas de processos gastroentéricos ocorridos na cidade de São Paulo. Ao longo das quatro décadas de estudo, descreve-se um ponto de ruptura entre a prevalência de resistência e a suscetibilidade na transição entre as décadas de 80 e 90. Embora o número de isolados de Salmonella ser. Typhimurium fagotipo 193 tenha aumentado no último período considerado, o percentual de mono e multirresistência aos antimicrobianos se situou em nível elevado (63,0%). A análise do polimorfismo obtido após macrorrestrição com a enzima XbaI revelou que cepas isoladas na década de 90 apresentaram elevado percentual de similaridade (≥85%) com cepas isoladas recentemente (período de 2000-2008), sendo agrupadas nos mesmos subclusters. Por outro lado, as cepas da década de 70 inserem-se em subclusters independentes, embora o percentual de similaridade entre tais subclusters e os demais seja ≥70%; o mesmo sendo observado para as cepas isoladas durante a década de 80. Em conclusão, este estudo mostrou que a prevalência de isolados humanos de Salmonella ser. Typhimurium fagotipo 193 no Brasil vem progredindo desde a década de 1990, enquanto a detecção do modelo R (ACSSuT) está diminuindo e a avaliação através da PFGE indicou a presença de multiplicidade de perfis de macrorrestrição no fagotipo 193, entretanto com elevados percentuais de similaridade entre si, sugerindo alguma clonalidade, tendo em vista o período entre o isolamento e a análise / To analyze strains of Salmonella ser. Typhimurium isolated from human cases of enteric and extraintestinal occurred during the period 1970 to 2008 of different regions of Brazil were selected, based on records in the database from Enterobacteria Laboratory of IOC / FIOCRUZ, RJ, samples prevalent phage type 193 in order to recognition of epidemic clones. We selected 553 strains of Salmonella ser. Typhimurium phage type 193 represented by 91, 65, 70 and 327 samples concerning the 1970s, 1980s, 1990s and the period from 2000 to 2008, respectively. In a global analysis of the sensitivity of these strains, 52% had one or more antibiotic resistance markers included in the profile ACSSuT. This resistance profile was found complete in 20.9% of isolates and the remaining 21.9%, sensitive to all drugs tested, especially in the period 2000 to 2008, represented by 121 samples (37.0%) compared the 327 cultures of that time. The highest percentage of resistance was observed in the samples of the 70 (99%) being the profile ACSSuT detected in 35.2% of isolates, emphasizing that all strains were isolated from gastrointestinal processes occurring in São Paulo city. Over the four decades of study, we describe a breaking point between the prevalence of resistance and susceptibility in the transition between the 1980s and 1990s. Although the number of isolates of Salmonella ser. Typhimurium phage type 193 has increased in the last period, the percentage of mono-and multidrug resistance to antimicrobial agents stood at high level (63.0%). The analysis of polymorphism obtained after macrorestriction with the enzyme XbaI showed that isolates in the 1990s showed a high percentage of similarity (≥ 85%) with strains isolated recently (2000-2008) and are grouped in the same subclusters. Moreover, the strains of the 1970s fall into subclusters independent, although the percentage of similarity between such subclusters and the other is ≥ 70%, the same was observed for the strains isolated during the 1980s. In conclusion, this study showed that the prevalence of human isolates of Salmonella ser. Typhimurium phage type 193 in Brazil has been progressing since the 1990s, while the detection of R model (ACSSuT) is decreasing and evaluation by PFGE indicated the presence of multiple profiles macrorestriction in phage type 193, however with high percentages of similarity, suggesting some clonality in view the period between isolation and analysis
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Avaliação da suscetibilidade antimicrobiana e do perfil de macrorrestrição do DNA de isolados humanos de Salmonella serovar Typhimurium fagotipo 193, no período de 1970 a 2008 / Evaluation of antimicrobial susceptibility and macrorestriction DNA of human isolates of Salmonella serovar Typhimurium phage type 193 in the period 1970 to 2008Eliane Moura Falavina dos Reis 09 June 2011 (has links)
Para analisar cepas de Salmonella ser. Typhimurium isoladas de processos entéricos e extraintestinais humanos ocorridos no período de 1970 a 2008 de diferentes regiões do país foram selecionadas, com base nos registros contidos no banco de dados do Laboratório de Enterobactérias do IOC/FIOCRUZ, RJ, amostras do fagotipo prevalente 193, visando precipuamente o reconhecimento de clones epidêmicos. Foram selecionadas 553 cepas de Salmonella ser. Typhimurium fagotipo 193 representadas por 91, 65, 70 e 327 amostras referentes as décadas de 70, 80, 90 e ao período de 2000 a 2008, respectivamente. Na análise global da sensibilidade destas cepas, 52% apresentaram um ou mais marcadores de resistência a antibióticos incluídos no perfil ACSSuT. Este perfil de resistência completo foi verificado em 20,9% dos isolados, sendo os 21,9% restantes, sensíveis a todas as drogas testadas, especialmente no período de 2000 a 2008, representadas por 121 amostras (37,0%) em relação as 327 culturas dessa época. O maior percentual de resistência foi observado nas amostras da década de 70 (99%) sendo o perfil ACSSuT detectado em 35,2% dos isolados, ressaltando-se que todas as amostras foram isoladas de processos gastroentéricos ocorridos na cidade de São Paulo. Ao longo das quatro décadas de estudo, descreve-se um ponto de ruptura entre a prevalência de resistência e a suscetibilidade na transição entre as décadas de 80 e 90. Embora o número de isolados de Salmonella ser. Typhimurium fagotipo 193 tenha aumentado no último período considerado, o percentual de mono e multirresistência aos antimicrobianos se situou em nível elevado (63,0%). A análise do polimorfismo obtido após macrorrestrição com a enzima XbaI revelou que cepas isoladas na década de 90 apresentaram elevado percentual de similaridade (≥85%) com cepas isoladas recentemente (período de 2000-2008), sendo agrupadas nos mesmos subclusters. Por outro lado, as cepas da década de 70 inserem-se em subclusters independentes, embora o percentual de similaridade entre tais subclusters e os demais seja ≥70%; o mesmo sendo observado para as cepas isoladas durante a década de 80. Em conclusão, este estudo mostrou que a prevalência de isolados humanos de Salmonella ser. Typhimurium fagotipo 193 no Brasil vem progredindo desde a década de 1990, enquanto a detecção do modelo R (ACSSuT) está diminuindo e a avaliação através da PFGE indicou a presença de multiplicidade de perfis de macrorrestrição no fagotipo 193, entretanto com elevados percentuais de similaridade entre si, sugerindo alguma clonalidade, tendo em vista o período entre o isolamento e a análise / To analyze strains of Salmonella ser. Typhimurium isolated from human cases of enteric and extraintestinal occurred during the period 1970 to 2008 of different regions of Brazil were selected, based on records in the database from Enterobacteria Laboratory of IOC / FIOCRUZ, RJ, samples prevalent phage type 193 in order to recognition of epidemic clones. We selected 553 strains of Salmonella ser. Typhimurium phage type 193 represented by 91, 65, 70 and 327 samples concerning the 1970s, 1980s, 1990s and the period from 2000 to 2008, respectively. In a global analysis of the sensitivity of these strains, 52% had one or more antibiotic resistance markers included in the profile ACSSuT. This resistance profile was found complete in 20.9% of isolates and the remaining 21.9%, sensitive to all drugs tested, especially in the period 2000 to 2008, represented by 121 samples (37.0%) compared the 327 cultures of that time. The highest percentage of resistance was observed in the samples of the 70 (99%) being the profile ACSSuT detected in 35.2% of isolates, emphasizing that all strains were isolated from gastrointestinal processes occurring in São Paulo city. Over the four decades of study, we describe a breaking point between the prevalence of resistance and susceptibility in the transition between the 1980s and 1990s. Although the number of isolates of Salmonella ser. Typhimurium phage type 193 has increased in the last period, the percentage of mono-and multidrug resistance to antimicrobial agents stood at high level (63.0%). The analysis of polymorphism obtained after macrorestriction with the enzyme XbaI showed that isolates in the 1990s showed a high percentage of similarity (≥ 85%) with strains isolated recently (2000-2008) and are grouped in the same subclusters. Moreover, the strains of the 1970s fall into subclusters independent, although the percentage of similarity between such subclusters and the other is ≥ 70%, the same was observed for the strains isolated during the 1980s. In conclusion, this study showed that the prevalence of human isolates of Salmonella ser. Typhimurium phage type 193 in Brazil has been progressing since the 1990s, while the detection of R model (ACSSuT) is decreasing and evaluation by PFGE indicated the presence of multiple profiles macrorestriction in phage type 193, however with high percentages of similarity, suggesting some clonality in view the period between isolation and analysis
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Efeito inibitÃrio de drogas antituberculose frente à Histoplasma capsulatum var. capsulatum e Cryptococcus spp.: sÃntese de anÃlogos quÃmicos, atividade antifÃngica in vitro e mecanismo de aÃÃo / Inhibitory effect of antituberculosis drugs against H. capsulatum var. capsulatum and Cryptococcus spp.: synthesis of chemical analogues, antifungal activity in vitro and mechanism of action.Francisca Jakelyne de Farias Marques 12 December 2013 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
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Avaliação da resistência de Mycobacterium tuberculosis a drogas através de testes fenotípicos, moleculares comerciais e do sequenciamento genômico total / Evaluation of Mycobacterium tuberculosis resistance to drugs through phenotypic, commercial molecular tests and whole genome sequencingCinara Silva Feliciano 23 February 2018 (has links)
A tuberculose (TB) embora passível de tratamento efetivo, ainda é um grave problema de saúde pública em diversos países, inclusive no Brasil. Nas últimas décadas houve progressos consistentes no controle da doença, porém o avanço da resistência bacilar ainda é um desafio a ser superado, já que os mecanismos da resistência são bastante complexos e não totalmente conhecidos, o que dificulta o desenvolvimento de testes de sensibilidade com elevada acurácia. O objetivo deste trabalho foi caracterizar as mutações gênicas de cepas de Mycobacterium tuberculosis de pacientes do Brasil e de Moçambique com doença resistente a drogas através do sequenciamento genômico total, além de descrever padrões de mutações obtidos por testes moleculares comerciais e comparar estes dados com resultados de testes fenotípicos. Estudo descritivo e transversal que incluiu 30 isolados (17 do Brasil e 13 de Moçambique), submetidos aos testes moleculares comerciais Genotype MTBDRplus®, Genotype MTBDRsl®, Xpert MTB/RIF® e teste fenotípico BACTEC MGIT 960 SIRE®. Todos os isolados também foram avaliados pelo sequenciamento genômico realizado pelo Illumina MiSeq Sequencing System® e submetidos a análise de mutações que conferem resistência às drogas contra TB utilizando o TB profiler online tool. A sensibilidade e especificidade do sequenciamento genômico para detecção de resistência a rifampicina foi de 87,5% e 92,3%, respectivamente. Além disso, o sequenciamento detectou a mutação (Val170Phe) no gene rpoB em dois isolados de M. tuberculosis de Moçambique. Esta mutação não é detectada pelos testes genotípicos comerciais. A sensibilidade do sequenciamento para a isoniazida foi de 95,6% e a especificidade de 100%. Para a estreptomicina, a sensibilidade foi de 85,7% e a especificidade de 93,3%. Para o etambutol, observamos sensibilidade de 100% e especificidade de 77,2%. As mutações mais frequentes associadas à resistência à rifampicina foram a Ser450Leu e a His445Tyr no gene rpoB. Em relação à isoniazida, predominou a mutação Ser315Thr no gene katG. O sequenciamento genômico, dado seu alto poder discriminatório, tem grande potencial de fornecer informações mais acuradas sobre mecanismo gênicos da resistência bacilar, possibilitando futuramente o aprimoramento de testes diagnósticos mais precisos. / Although there is an effective treatment for tuberculosis (TB), it is still a serious public health problem in several countries, including Brazil. In the last decades, there has been consistent progress in disease control, but the increasing number of disease caused by resistant strains is still a challenge to be overcome, since the mechanisms of resistance are quite complex and not fully known, which difficult the development of susceptibility tests with high accuracy. The aim of this work was to characterize gene mutations of Mycobacterium tuberculosis strains from Brazilian and Mozambican patients with drug-resistant disease through whole genome sequencing, as well as to describe patterns of mutations obtained by commercial molecular tests and to compare these data with results of phenotypic susceptibility tests. It was a cross-sectional study that included 30 isolates (17 from Brazil and 13 from Mozambique). Commercial molecular tests Genotype MTBDRplus(TM), Genotype MTBDRsl(TM), Xpert MTB / RIF(TM) and BACTEC MGIT 960 SIRE(TM) phenotypic test were performed for all isolates. All of them were also evaluated by whole genome sequencing performed by the Illumina MiSeq Sequencing System(TM) and submitted to analysis of mutations that confer drug resistance against TB using the TB profiler online tool. The sensitivity and specificity of whole genome sequencing for detection rifampicin resistance was 87.5% and 92.3%, respectively. Also, whole genome sequencing detected the mutation (Val170Phe) in the rpoB gene in two isolates of M. tuberculosis from Mozambique. This mutation is not detected by commercial genotypic tests. The sensitivity of the whole genome sequencing for isoniazid was 95.6%, and the specificity was 100%. For streptomycin, the sensitivity was 85.7%, and the specificity was 93.3%. For ethambutol, we observed a sensitivity of 100% and specificity of 77.2%. The most frequent mutations associated with rifampicin resistance were rpoB Ser450Leu and His445Tyr. About isoniazid, the katG Ser315Thr mutation was the most frequent. Whole genome sequencing, given its high discriminatory power, has great potential to provide more accurate information about the gene mechanisms of bacilli resistance, making possible the improvement of more accurate diagnostic tests in the future.
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