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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Etiologia e resist?ncia bacteriana em unidades de terapia intensiva atrav?s de culturas de vigil?ncia

Franco, Mayara Maria Bastos 29 March 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-07-04T11:53:11Z No. of bitstreams: 1 MayaraMariaBastosFranco_DISSERT.pdf: 2345421 bytes, checksum: cac97047a722e5ab5047a164b245b028 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-07-11T12:49:30Z (GMT) No. of bitstreams: 1 MayaraMariaBastosFranco_DISSERT.pdf: 2345421 bytes, checksum: cac97047a722e5ab5047a164b245b028 (MD5) / Made available in DSpace on 2017-07-11T12:49:30Z (GMT). No. of bitstreams: 1 MayaraMariaBastosFranco_DISSERT.pdf: 2345421 bytes, checksum: cac97047a722e5ab5047a164b245b028 (MD5) Previous issue date: 2017-03-29 / A exist?ncia de pat?genos com alto perfil de resist?ncia, colonizando a pele e mucosas de pacientes internados, elevam o risco da ocorr?ncia de infec??es graves. Deste modo as culturas de vigil?ncia s?o importantes a fim de se identificar estes microrganismos e minimizar a sua propaga??o para outros indiv?duos. Este estudo utilizou culturas de vigil?ncia para determinar o perfil de resist?ncia presente em bact?rias isoladas de 114 pacientes internados em Unidades de Terapia Intensiva (UTIs). Utilizou-se m?todos de identifica??o fenot?pica, de sensibilidade aos antibi?ticos e testes fenot?picos de indica??o de produ??o de ?-lactamases. Das amostras de Staphylococcus spp. isoladas, 89% (98/110) apresentaram resist?ncia ? Oxacilina, 39% (52/133) das enterobact?rias eram produtoras de ?-lactamase de Espectro Estendido, 57,5% (23/40) das Pseudomanoas aeruginosa eram produtoras de ?-lactamase AmpC e 80% (30/37) dos Acinetobacter spp. eram resistentes aos carbapen?micos. Dentre as vari?veis cl?nicas estudadas, encontrou-se uma associa??o estatisticamente significativa entre o uso de carbapen?micos e a coloniza??o por bact?rias resistentes aos antibacterianos mais frequentes utilizados na rotina. Estes ?ndices elevados refletem a tend?ncia epidemiol?gica atual do crescimento das bact?rias com alto padr?o de resist?ncia, tornando-se essencial a implementa??o de medidas de vigil?ncia, isolamento e racionaliza??o do uso de antibi?ticos a fim de se minimizar a dissemina??o destes pat?genos. / The existence of pathogens with high antimicrobial resistance, colonizing the skin and mucous membranes of hospitalized patients, increases the risk of serious infections. Thus surveillance cultures are important to identify these microorganisms and minimize their propagation to other individuals. This research used surveillance cultures to determine the resistance profile existent in bacteria colonizing 114 patients admitted in Intensive Care Units (ICUs) for 7 or more days. For this purpose, manual methods of phenotypic identification, antimicrobial susceptibility and phenotypic tests for the indication of ?-lactamase? production were used. From the Staphylococcus spp. isolated, 89% (98/110) were resistant to oxacillin, 39% (52/133) of Enterobacteriaceae were producers of Extended Spectrum ?-Lactamases, 57.5% (23/40) of Pseudomonas aeruginosa were producers of AmpC ?-Lactamase and 81% (30/37) of Acinetobacter spp. were resistant to carbapenems. Among the studied clinical variables, it was found a significant statistical association between the use of carbapenems and colonization by bacteria resistant to these antibiotics. These high indexes reflect the current epidemiological tendency of high resistant bacteria growth, making essential the implementation of surveillance measures, isolation and rationalization of antibiotic use to minimize the dissemination of these pathogens.
2

Caracteriza??o fenogenot?pica da resist?ncia antimicrobiana em Staphylococcus spp. isolados de mastites cl?nicas e subcl?nicas em unidades leiteiras de munic?pios do Rio de Janeiro como subs?dio para implementa??o de medidas de controle / Fenogenot?pica Characterization of antimicrobial resistance in Staphylococcus spp. isolated from clinical or subclinical mastitis in dairy units of municipalities of Rio de Janeiro as a subsidy for implementation of control measures.

Mendon?a, Elaine Concei??o Liporage de 16 March 2012 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-07-26T14:34:03Z No. of bitstreams: 1 2012 - Elaine Concei??o Liporage de Mendon?a.pdf: 3515906 bytes, checksum: ebf489151f2cd6961ddeeb292cd910a7 (MD5) / Made available in DSpace on 2017-07-26T14:34:03Z (GMT). No. of bitstreams: 1 2012 - Elaine Concei??o Liporage de Mendon?a.pdf: 3515906 bytes, checksum: ebf489151f2cd6961ddeeb292cd910a7 (MD5) Previous issue date: 2012-03-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The use of antibiotic in the control of intramammary infections and in the elimination of its possible sources in dairy farms is an important control measure. However, the inappropriate use of antibiotics can result in the appearance of resistant strains and compromise the efficiency of the treatment. Besides Staphylococcus spp. are among the main pathogens of bovine mastitis, they are often resistant to antibiotics, especially beta-lactamics, mainly by two distinct mechanisms: the production of extracellular enzyme beta-lactamase, encoded by the blaZ gene, and production of PBP2a or PBP2 ' a penicillin-binding protein with low affinity, encoded by the mecA gene. The expression of mecA gene is constitutive or induced by beta-lactamic antibiotics, such as oxacillin and cefoxitin. The mecA gene is inserted into the chromosome through a staphylococcal mobile genetic element, called staphylococcal cassette chromosome mec (SCCmec). The present study evaluated the phenogenotypical resistance profile to betalactam antibiotics of 250 Staphylococcus spp. isolates, using oxacillin and cefoxitin as markers in order to produce data to the knowledge of resistance in dairy farms located in the South-Fluminense and the Metropolitan regions of the State of Rio de Janeiro to support the implementation of measures to control this disease. The assessment of resistance was made through 8 different phenotypic tests and yielded 54 profiles. Disk diffusion and agar screen with oxacillin were used as "gold standard" for the calculation of sensitivity, specificity and prediction once they are recommended by the CLSI veterinarian as standardized tests. Disk diffusion with cefoxitin achieved the best performance in the prediction of oxacillin resistance. Genotypic detection of mecA do not provided any positive isolate, otherwise mecI and mecRI genes were also detected in 11.6% (29/250) of the studied Staphylococcus spp. Four cassette mec types were detected (I, II, III and IV), being type I the most disseminated one. Gene blaZ was detected in 5.2% (13/250) isolates. From these 13 blaZ positive isolates, the whole system comprising blaR1-blaI-blaZ was detected in 23.1% (3/13) isolates / MENDON?A, Elaine Concei??o Liporage. Caracteriza??o fenogenot?pica da resist?ncia antimicrobiana em Staphylococcus spp. isolados de mastites cl?nicas e subcl?nicas em unidades leiteiras de munic?pios do Rio de Janeiro como subs?dio para implementa??o de medidas de controle. 89 p. Disserta??o (Mestrado em Ci?ncias Veterin?rias). Instituto de Veterin?ria, Departamento de Parasitologia Animal, Universidade Federal Rural do Rio de Janeiro, Serop?dica, RJ, 2012. A utiliza??o de antibi?ticos no controle das infec??es intramam?rias e na elimina??o de prov?veis fontes de infec??o nas fazendas leiteiras se constitui em importante medida de controle. No entanto, o uso inadequado de antibi?ticos no tratamento da doen?a pode gerar o aparecimento de cepas resistentes e comprometer a efici?ncia do tratamento. Bact?rias do g?nero Staphylococcus spp. est?o entre os principais agentes etiol?gicos da mastite bovina e s?o freq?entemente resistentes aos antimicrobianos, em especial aos beta-lact?micos, principalmente por dois mecanismos distintos: a produ??o da enzima extracelular beta-lactamase, codificada pelo gene blaZ, e a produ??o de PBP2a ou PBP2?, uma prote?na ligante de penicilina de baixa afinidade, codificada pelo gene mecA. A express?o do gene mecA ? constitutiva ou induzida por antibi?ticos betalact?micos, como a oxacilina e cefoxitina. O gene mecA est? inserido no cromossomo estafiloc?cico atrav?s de um elemento gen?tico m?vel, denominado cassete estafiloc?cico cromoss?mico mec (SCCmec). O presente estudo avaliou o perfil fenogenot?pico de resist?ncia aos beta-lact?micos em 250 isolados de Staphylococcus spp, utilizando os marcadores oxacilina e cefoxitina, de modo a produzir dados que possam contribuir para o conhecimento da resist?ncia antimicrobiana em algumas propriedades leiteiras das regi?es Sul-Fluminense e Metropolitana do Estado do Rio de Janeiro com o objetivo de subsidiar a implementa??o de medidas de controle dessa enfermidade. A avalia??o da resist?ncia foi feita a partir de 8 diferentes testes fenot?picos, sendo obtidos 54 perfis. Os testes de difus?o em disco simples e ?gar screen com oxacilina foram utilizados como ?padr?o ouro? para os c?lculos dos valores de sensibilidade, especificidade e predi??o por serem preconizados pelo CLSI veterin?rio. O teste de difus?o em disco simples com cefoxitina foi o de melhor desempenho na predi??o da resist?ncia a oxacilina. Na avalia??o genot?pica, n?o foi detectado qualquer isolado positivo para o gene mecA, j? os genes mecI e mecRI foram detectados igualmente em 11,6% (29/250) dos Staphylococcus spp avaliados. Foram detectados os quatro tipos de cassete mec analisados (I, II, III e IV), sendo o tipo I o que teve mais ampla distribui??o entre as regi?es estudadas. Gene blaZ foi detectado em 5,2% (13/250) dos isolados, sendo que nestes, todo o sistema blaZ-blaI- blaR1 foi detectado em 23,1% (3/13) dos isolados.
3

Express?o g?nica na forma??o do biofilme e resist?ncia aos beta-lact?micos em isolados de Staphylococcus aureus provenientes de leite mast?tico bovino / Gene expression in biofilm formation and resistance to beta-lactam in Staphylococcus aureus isolates from bovine milk mastitic

Marques, Viviane Figueira 02 March 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-10-03T16:25:38Z No. of bitstreams: 1 2016 - Viviane Figueira Marques.pdf: 1883187 bytes, checksum: 9996d5ea41ecd4f93424c808c4d82ba6 (MD5) / Made available in DSpace on 2017-10-03T16:25:38Z (GMT). No. of bitstreams: 1 2016 - Viviane Figueira Marques.pdf: 1883187 bytes, checksum: 9996d5ea41ecd4f93424c808c4d82ba6 (MD5) Previous issue date: 2016-03-02 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Staphylococcus spp. plays an important role in the etiology of bovine mastitis. Staphylococcus aureus is considered the most relevant specie due to the production of virulence factors such as ?slime?, which is required for biofilm formation. This study aimed to detect the phenotypic expression of the biofilm formation in 20 S. aureus isolates from bovine mastitis, to detect and quantify the expression of genes involved in its production and regulation, as well as to detect the phenogenotypic resistance to beta-lactam in order to evaluate the possible relation between biofilm production and antimicrobial resistance. The isolates were characterized by MALDI-TOF and phenogenotypic identification assays. Also they were submitted to the phenotypic tests to evaluate biofilm production and the susceptibility to beta-lactams. Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Minimum Inhibitory Concentration in the Biofilm (MICB) were determined to three isolates presenting distinct biofilm production. Futherly, a PCR for the detection of ?slime? production genes (icaA and icaD), Bap protein (bap), beta-lactamase (blaZ) and protein altered penicillin-binding (mecA). Also, the Agr system was typified (agr I, agr II, agr III and agr IV) and its regulator (agr RNAIII) was detected. Scanning Electron Microscopy (SEM) was performed to determine the most suitable time interval for biofilm analysis. Real-time PCR (qPCR) was performed at the chosen times to quantify the expression of icaA, icaD and hld genes in the three studied isolates. All 20 isolates were biofilm producers and most presented icaA and icaD genes. Only one isolate presented the bap gene. The agr gene type II presented a prevalence of 70%. The SEM showed gradual changes in bacterial arrangement during the biofilm formation along the phases of the growth curve. The peak was reached at the stationary phase. Transcriptional analysis revealed increased expression of ica genes at 8 h of growth and of hld at 24 h. However, for the N-365 strain the ica expression was of low yield. For this study, the penicillin resistance was related to the production of beta-lactamase otherwise the high MBC detected for cefoxitin may be associated to biofilm protection, evidentiated by the fact that the isolates have MICB values higher than MICs tested for planktonic cells / Staphylococcus spp. tem papel importante na etiologia da mastite bovina. Staphylococcus aureus ? considerada a esp?cie mais relevante devido ? produ??o de fatores de virul?ncia, tais como ?slime?, o que favorece a forma??o do biofilme. O presente trabalho teve por objetivo detectar a express?o fenot?pica da forma??o de biofilme em 20 isolados de S. aureus oriundos de mastite bovina, detectar e quantificar a express?o dos genes envolvidos na sua produ??o e regula??o, al?m de detectar a resist?ncia fenogenot?pica aos beta-lact?micos para avalia??o da poss?vel rela??o da produ??o de biofilme com a resist?ncia antimicrobiana. Os isolados foram caracterizados atrav?s de testes fenogenot?picos e MALDI-TOF, submetidos ?s provas fenot?picas de detec??o da forma??o de biofilme e avalia??o da suscetibilidade aos beta-lact?micos. A Concentra??o Inibit?ria M?nima (CIM), Concentra??o Bactericida M?nima (CBM) e a Concentra??o Inibit?ria M?nima no Biofilme (CIMB) foram determinadas para tr?s isolados selecionados com base na varia??o da intensidade da produ??o de biofilme. Posteriormente, todos os isolados foram submetidos ? t?cnica de PCR para detec??o dos genes de produ??o de ?slime? (icaA e icaD), prote?na Bap (bap), beta-lactamase (blaZ) e prote?na ligante de penicilina alterada (mecA). Al?m de detec??o do sistema regulador Agr (agr RNAIII) e da tipifica??o do sistema Agr (agr I, agr II, agr III e agr IV). Foi realizada Microscopia Eletr?nica de Varredura (MEV) para determinar o intervalo de tempo mais adequado para a an?lise do biofilme. A PCR em tempo real (qPCR) foi realizada nos tempos selecionados para quantificar a express?o dos genes icaA, icaD e hld em tr?s isolados com produ??o variada de biofilme. Todos os isolados foram produtores de biofilme e a maioria apresentou os genes icaA e icaD. Apenas um isolado apresentou o gene bap. O gene agr tipo II mostrou preval?ncia de 70%. A MEV mostrou mudan?as graduais no arranjo bacteriano durante a forma??o de biofilme ao longo das fases da curva de crescimento que atingiu seu pico de forma??o na fase estacion?ria. A an?lise transcricional evidenciou maior express?o dos genes ica no tempo de 8 h de crescimento e hld em 24 h. Contudo, a cepa N-365 mostrou baixa produ??o dos genes ica. Para este estudo, a resist?ncia ? penicilina foi relacionada com a produ??o de beta-lactamase, enquanto a elevada CBM detectada para cefoxitina pode estar associada ? prote??o que o biofilme oferece, epis?dio evidenciado pelo fato dos isolados apresentarem valores de CIMB superiores aos CIMs testados para as c?lulas planct?nicas.
4

Resist?ncia bacteriana em reservat?rio do semi?rido brasileiro: caracteriza??o, a??o para vigil?ncia ambiental, preven??o e educa??o em sa?de

Nascimento, Ermeton Duarte do 29 April 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-10-11T23:01:26Z No. of bitstreams: 1 ErmetonDuarteDoNascimento_TESE.pdf: 7719427 bytes, checksum: b84ff037c2d66bf7a8b825c76b7b9db3 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-10-18T00:19:26Z (GMT) No. of bitstreams: 1 ErmetonDuarteDoNascimento_TESE.pdf: 7719427 bytes, checksum: b84ff037c2d66bf7a8b825c76b7b9db3 (MD5) / Made available in DSpace on 2016-10-18T00:19:26Z (GMT). No. of bitstreams: 1 ErmetonDuarteDoNascimento_TESE.pdf: 7719427 bytes, checksum: b84ff037c2d66bf7a8b825c76b7b9db3 (MD5) Previous issue date: 2016-04-29 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A resist?ncia aos antimicrobianos se transformou num s?rio problema de sa?de p?blica mundial e v?rios ambientes aqu?ticos se apresentam contaminados por esses microrganismos. Entretanto, n?o h? dados sobre esse fen?meno para o semi?rido brasileiro. Sendo assim, este estudo teve como objetivo o isolamento e a identifica??o das bact?rias de import?ncia m?dica contaminantes de ambientes qu?ticos no semi?rido potiguar, a caracteriza??o da resist?ncia antimicrobiana, e a formula??o de propostas para educa??o em sa?de e a??es para vigil?ncia ambiental em sa?de. Com este prop?sito foram coletadas amostras de ?gua de quatro reservat?rios do semi?rido potiguar durante os per?odos seco e chuvoso. As amostras foram processadas e os microrganismos foram isolados e identificados seguindo orienta??es de bibliografias especializadas. Em seguida foram realizados os testes de sensibilidade antimicrobiana em disco difus?o, calculado o ?ndice de m?ltipla resist?ncia antibi?tica (MAR) e classificados os organismos com multipla resist?ncia ?s drogas (MDR). Tamb?m foram propostas a??es para preven??o e educa??o em sa?de, bem como para vigil?ncia ambiental em sa?de. Adicionalmente, foi avaliada, na Universidade de Minnesota, nos Estados Unidos, a influ?ncia da concentra??o do f?sforo em meio l?quido (caldo nutriente, C:P 100:1, 1000:1 e 100.000:1) sobre a expres?o fenot?pica da resist?ncia ? tetraciclina, ao cloranfenicol e a eritromicina, de 41 cepas bacterianas dos Estados Unidos utilizando a t?cnica da Concentra??o Inibit?ria M?nima (CIM) e da Concentra??o Bactericida M?nima (CBM). Ao todo foram isoladas 168 bact?rias, 56% no per?odo chuvoso, com 97,6% pertecentes ao grupo das Gram-negativas, com a Fam?lia Enterobacteriaceae apresentando a maior preval?ncia entre esse grupo (73,2%). 95,3% das bact?rias resistentes aos antimicrobianos foram isoladas durante o per?odo seco e o ?ndice MAR foi maior no reservat?rio Passagem das Tra?ras, com 56% de chance para que as bact?rias encontradas na ?gua desse reservat?rio procedam de uma fonte de contamina??o com maior risco para a sa?de humana. N?o houve diferen?a estat?stica da ocorr?ncia de g?neros e esp?cies bacterianos entre os per?odos seco e chuvoso e nem entre os reservat?rios, com p=0,255. Tamb?m n?o houve diferen?a estat?stica do ?ndice MAR entre os per?odos e os reservat?rios, com p=0,224. Quando avaliada a CIM, o meio com C:P de 100.000:1, considerado com a menor concentra??o de f?sforo, parece aumentar a sensibilidade das bact?rias ao cloranfenicol e a eritromicina quando comparado aos resultados do caldo nutriente para os mesmos antimicrobianos, com um p=0,023. Nas escolas que atendem as comunidades ribeirinhas usu?rias da ?gua dos reservat?rios, s?o propostas a??es de educa??o em sa?de que visem o levantamento de concep??es sobre o conhecimento do uso dos antimicrobianos e do surgimento da resist?ncia bacteriana a essas drogas, bem como o desenvolvimento de material para educa??o em sa?de. E no n?cleo de Vigil?ncia Ambiental em Sa?de da SESAP, s?o propostas a inclus?o das bact?rias resistentes aos antimicrobianos isoladas de ambientes aqu?ticos como indicadores de risco para a sa?de p?blica, a formula??o de pol?ticas p?blicas visando o controle das atividades que contaminam esses recursos com esses organismos e tamb?m o monitoramento peri?dico da ?gua dos diversos ambientes aqu?ticos. / Bacterial resistance to antimicrobials became a serious public health problem around the world, and different aquatic environments are contaminated with these organisms. However, there is no data about this phenomenon in the Brazilian semiarid region. Therefore, this study had as main the isolation and identification of contaminant harmful bacteria of potiguar semiarid aquatic environments, characterization of antimicrobial resistance, development of proposals in health education and actions for environmental health surveillance. With this purpose were collected water samples from four potiguar semiarid reservoirs during dry and rainy season. Those samples were analyzed and microorganisms were isolated and identified following specialized literature orientation. Then antimicrobials susceptibility disk diffusion test were performed, Multiple Antibiotic Resistance (MAR) index was calculated, and Multiple Drug Resistance (MDR) classification was used. Also were proposed actions for health prevention and education. In addiction, was evaluated, in Minnesota University/United States of America, the influence of phosphorus concentration in broth medium (Nutrient broth, 100:1, 1000:1 and 100.000:1 C:P ratio) over phenotypic resistance expression to tetracycline, chloramphenicol and erythromycin in 41 American aquatic bacterial strains by using Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) techniques. Altogether were isolated 168 bacteria from the Brazilian semiarid reservoirs, 56% in rainy season, with 97,6% from Gram-negative group, and 73,2% from Enterobacteriaceae Family. Ninety five point three percent of antimicrobial resistant bacteria were isolated during dry season and MAR index was higher for Passagem das Tra?ras reservoir, with 56% of chance that bacteria found in that reservoir has proceeded from high risk source of contamination for human health. There were no statistical differences of bacterial genera and species occurrence between dry and rainy season nor between reservoirs, with p=0,255. Also, there were no statistical differences in MAR index between seasons nor between reservoirs, with p=0,244. When MIC was evaluated, the 100.000:1 C:P ratio medium, considered the one with lower concentration of phosphorus, seemed to increase bacterial susceptibility to chloramphenicol and erythromycin when comparing to nutrient broth results for the same antimicrobials, with p=0,023. At schools that serve riverine communities water reservoirs user were proposed activities for health education aiming describe conceptions about antimicrobial use knowledge and the emergency of bacterial resistance to those drugs, as well as the development of materials for health education. At SESAP Environmental Health Surveillance group were proposed inclusion of antimicrobial resistant bacteria isolated in aquatic environments as indicator of risk for public health, as well as formulation of public policies to control activities that contaminate these sources with those organisms, and also the water periodic monitoring of several aquatic environments.

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