Made available in DSpace on 2014-06-11T19:32:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-26Bitstream added on 2014-06-13T20:24:18Z : No. of bitstreams: 1 oliveira_ac_dr_jabo.pdf: 650394 bytes, checksum: 3022a3790349efbed366f6fa0374267e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foram estudadas 180 amostras de água de 45 consultórios odontológicos da cidade de Barretos-SP, com o objetivo de isolar, identificar, determinar a contagem de isolados de Pseudomonas aeruginosa UFC/mL, determinar o perfil clonal e avaliar a diversidade genômica dos isolados e a suscetibilidade das mesmas frente a diferentes antibióticos. As amostras de água foram filtradas em filtro Millipore® e a membrana colocada sobre o centro de uma placa de Petri contendo agar cetrimida, As colônias típicas de bactérias do gênero Pseudomonas foram identificadas pelo método de Gram, inoculação em TSI agar (Triple Sugar Iron), crescimento a 42ºC, produção de pigmento, produção de alginato, oxidase, motilidade e alcalinização da acetamida. O teste utilizado para análise genômica foi o ERIC-PCR. Dos 76 (42,2%) isolados de Pseudomonas aeruginosa, 15 eram provenientes das amostras de torneira de lavagem das mãos, 18 de reservatório de garrafa pet, 23 de seringa tríplice e 20 do motor de alta rotação. Todos os isolados de Pseudomonas aeruginosa foram submetidos ao teste de suscetibilidade segundo a técnica de Kirby- Bauer. Dos antibióticos testados o que apresentou melhor resultado quanto à sensibilidade (65,8%) foi a ciprofloxacina. Quanto à similaridade genética dos isolados dos diferentes pontos analisados, foram encontrados nove “clusters” de 100% de similaridade. / The biofilm found in water supplies and lines of hospitals and dental units is extremely important because it presents a large number of bacteria, leading to risk of infection in immunocompromised patients vulnerable to opportunistic pathogens such as the Pseudomonas aeruginosa. One hundred eighty water samples from dental units of the city of Barretos-SP were evaluated. The water samples filtered in Millipore® filter were incubated in plates containing Cetrimide ágar. The bacteria colonies were identified through the gram-staining test, inoculation in agar T.S.I (triple sugar Iron), growth at 42 ° C, pigment production, production of alginate, oxidase acetamide alkalization and motility observation. All Pseudomonas aeruginosa bacteria were submitted to the susceptibility test according to the Kirby-Bauer technique. The test used for genomic analysis was the ERIC-PCR. From the total microorganisms studied, 76 (42,2%) were positive for Pseudomonas aeruginosa, isolates from 180 water samples, where 15 strains were from hand washing incoming local water supplies, 18 from PET bottled water, 23 from 3-in-1 syringes and 20 from the high speed handpiece. In relation to the antibiotics tested, the one presenting the best result with regard to sensibility was ciprofloxacin with 65.8%. The genetic similarity of isolates from different points analyzed, there were nine clusters of 100% similarity.

Orientador: Fernando Antônio de Ávila / Banca: José Moacir Marim / Banca: Patricia Amoroso / Banca: Simone Barone Salgado Marques / Banca: Tammy Priscilla Chioda Delfino / Resumo: Foram estudadas 180 amostras de água de 45 consultórios odontológicos da cidade de Barretos-SP, com o objetivo de isolar, identificar, determinar a contagem de isolados de Pseudomonas aeruginosa UFC/mL, determinar o perfil clonal e avaliar a diversidade genômica dos isolados e a suscetibilidade das mesmas frente a diferentes antibióticos. As amostras de água foram filtradas em filtro Millipore® e a membrana colocada sobre o centro de uma placa de Petri contendo agar cetrimida, As colônias típicas de bactérias do gênero Pseudomonas foram identificadas pelo método de Gram, inoculação em TSI agar (Triple Sugar Iron), crescimento a 42ºC, produção de pigmento, produção de alginato, oxidase, motilidade e alcalinização da acetamida. O teste utilizado para análise genômica foi o ERIC-PCR. Dos 76 (42,2%) isolados de Pseudomonas aeruginosa, 15 eram provenientes das amostras de torneira de lavagem das mãos, 18 de reservatório de garrafa pet, 23 de seringa tríplice e 20 do motor de alta rotação. Todos os isolados de Pseudomonas aeruginosa foram submetidos ao teste de suscetibilidade segundo a técnica de Kirby- Bauer. Dos antibióticos testados o que apresentou melhor resultado quanto à sensibilidade (65,8%) foi a ciprofloxacina. Quanto à similaridade genética dos isolados dos diferentes pontos analisados, foram encontrados nove "clusters" de 100% de similaridade. / Abstract: The biofilm found in water supplies and lines of hospitals and dental units is extremely important because it presents a large number of bacteria, leading to risk of infection in immunocompromised patients vulnerable to opportunistic pathogens such as the Pseudomonas aeruginosa. One hundred eighty water samples from dental units of the city of Barretos-SP were evaluated. The water samples filtered in Millipore® filter were incubated in plates containing Cetrimide ágar. The bacteria colonies were identified through the gram-staining test, inoculation in agar T.S.I (triple sugar Iron), growth at 42 ° C, pigment production, production of alginate, oxidase acetamide alkalization and motility observation. All Pseudomonas aeruginosa bacteria were submitted to the susceptibility test according to the Kirby-Bauer technique. The test used for genomic analysis was the ERIC-PCR. From the total microorganisms studied, 76 (42,2%) were positive for Pseudomonas aeruginosa, isolates from 180 water samples, where 15 strains were from hand washing incoming local water supplies, 18 from PET bottled water, 23 from 3-in-1 syringes and 20 from the high speed handpiece. In relation to the antibiotics tested, the one presenting the best result with regard to sensibility was ciprofloxacin with 65.8%. The genetic similarity of isolates from different points analyzed, there were nine clusters of 100% similarity. / Doutor

La contamination microbienne des units de soins dentaires (USD) est connue depuis les années 60. L'eau circule à l'intérieur des USD dans des conditions favorables au développement d'un biofilm (faible débit, nature des surfaces, stagnation). Ce biofilm, réservoir de micro-organismes potentiellement pathogènes, peut représenter un risque infectieux pour les patients et le personnel dentaire exposés à l'eau et aux aérosols générés lors des soins dentaires, en particulier s'ils sont immunodéprimés.Des micro-organismes provenant de l'eau, tels que les amibes libres, peuvent être retrouvés dans ce biofilm. Des protozoaires ubiquitaires de l'environnement du genre Acanthamoeba ou Hartmannella, connus comme pathogènes opportunistes chez l'Homme (kératites, méningo-encéphalites) et ayant la capacité de servir d'hôte pour le développement intracellulaire de certains microorganismes pathogènes (ex : Legionella pneumophila), ont en effet été isolés dans l'eau des USD.D'autre part, des micro-organismes provenant de la cavité buccale d'un patient peuvent également se retrouver dans le système d'eau des USD, en même temps que des traces de salive et/ou de sang, suite à un dysfonctionnement ou un mauvais entretien des valves anti-reflux des porte-instruments rotatifs. Les levures du genre Candida sont des commensaux du tube digestif humain, pathogènes opportunistes notamment responsables d'infections oro-pharyngées, et parfois retrouvées dans les USD.Ce travail a consisté d'une part en l'étude de la capacité de deux amibes libres : A. castellanii et H. vermiformis, ainsi que de trois espèces de Candida : C. albicans, C. glabrata et C. parapsilosis, à survivre dans l'eau, en présence ou non de salive. Les résultats montrent une influence dose-dépendante et espèce-dépendante de la salive sur la survie des trois levures, et aucun effet sur la viabilité des amibes. Des interactions ont pu être mises en évidence entre amibes libres et levures : A. castellanii est capable d'internaliser puis de digérer les trois espèces de levures, induisant leur élimination rapide, indépendamment de la présence de salive. En revanche, H. vermiformis permet la survie et la prolifération de Candida spp. dans l'eau, même en l'absence de salive.Enfin, dans une démarche de prévention et de lutte contre le risque infectieux lié à l'eau des USD, l'efficacité de différents traitements chimiques communément utilisés : le chlore (NaOCl), le peroxyde d'hydrogène (H2O2) et l'Oxygenal 6©, a été étudiée sur les différentes espèces de Candida et d'amibes libres. Ces traitements montrent une efficacité variable : le chlore requiert l'utilisation de concentrations élevées (>26 ppm) et peu compatibles avec l'usage courant des USD. Le H2O2 ne présente pas d'activité significative dans les conditions testées (de 0.07% à 0.9% v/v). En revanche, l'Oxygenal 6© apparaît le plus efficace pour l'éradication des levures du genre Candida et des amibes libres dans l'eau (dès 0.05%). / Microbial contamination of dental unit waterlines (DUW) is known since the 60's. Water circulates throughout DUW with environmental conditions encouraging biofilm development (low flow, surface material, stagnation). This biofilm, which is a reservoir of potentially pathogenic micro-organisms, may represent an infectious risk for patients and dental staff exposed to water and aerosols generated during dental cares, in particular for immunocompromised persons. Micro-organisms coming from water, such as free-living amoebae (FLA), may be isolated in this biofilm. Protozoa belonging to Acanthamoeba or Hartmannella genera are ubiquitous in the environment; they are known to be opportunistic pathogens for Human (keratitis, meningo-encephalitis), to encourage intracellular development of some pathogenic micro-organisms (for example: Legionella pneumophila), and they have already been isolated in DUW.On the other hand, micro-organisms coming from the oral cavity of an infected patient may also be isolated in DUW water, mixed with saliva traces and/or blood, mainly because of the dysfunction or the poor maintenance of anti-retraction valves. Candida yeasts colonize human's oral cavity and digestive tract as commensals or opportunistic pathogens, thus implicated in oro-pharyngeal infections; they are sometimes isolated in DUW.This work focused first on the study of the survival capacity of two species of FLA: A. castellanii and H. vermiformis, and three species of yeasts: C. albicans, C. glabrata and C. parapsilosis, in water, with or without saliva. Results showed that the addition of saliva permitted both survival and proliferation of all three tested Candida species whereas no effect was observed on FLA growth. Then, interactions have been demonstrated between FLA and yeasts: A. castellanii were able to internalize and then digest the three tested yeasts species, inducing their rapid degradation, independently of saliva presence. Conversely, H. vermiformis were able to promote Candida survival and proliferation in water, with or without saliva.Finally, in order to prevent and fight against infectious risk associated with DUW water, the efficacy of commonly used chemical treatments: chlorine (NaOCl), hydrogen peroxide (H2O2) and Oxygenal 6©, was studied against the three species of Candida and the two species of FLA. These treatments showed a variable efficacy: chlorine was effective only using the highest tested concentrations (> 14 ppm), which are not compatibles with DUW use. H2O2 displayed no significant activity in the experimental conditions (0.07% to 0.9% v/v). Oxygenal 6© seemed to be the more effective for eradication of Candida yeasts and FLA, in water (even with 0.05% v/v).