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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.
41

Análise da diversidade genética por MLSA e avaliação da atividade antitumoral de linhagens de Chromobacterium sp. / Genetic diversity analysis by MLSA and antitumoral activity evaluation of Chromobacterium sp. strains.

Menezes, Cláudia Beatriz Afonso de 22 January 2009 (has links)
A diversidade genética dos isolados de Chromobacterium sp. foi avaliada por Multilocus sequence analysis com base nas análises dos genes conservados rpoA, lepA, gyrB, fusA e rRNA 16S. A análise do gene rRNA 16S e MLSA agrupou os isolados no gênero Chromobacterium, entretanto, cinco dos isolados estão distantes filogeneticamente das linhagens tipo, C. violaceum e C. subtsugae, sugerindo duas novas espécies. Os extratos brutos, obtidos por soxhlet, dos isolados de Chromobacterium sp., testados em ensaios in vitro em células tumorais humanas, apresentaram atividades antitumorais potenciais e seletivas para determinadas linhagens celulares. Os extratos brutos e frações foram analisados por HPLC-DAD para avaliação da presença ou ausência da violaceína. Além disso, outros metábólitos secundários que não a violaceína podem estar relacionados à atividade antitumoral. / The genetic diversity of strains of Chromobacterium sp was evaluated by Multilocus sequence analysis (MLSA) based on the analysis of conserved genes rpoA, recA, lepA, gyrB, fusA and rRNA 16S. The analysis of 16S ribosomal RNA gene grouped all isolates in the genus Chromobacterium, however, the five isolates are phylogenetically distant of type strain C. violaceum and C. subtsugae, suggesting new species. The crude extracts of the isolates from Chromobacterium sp., obtained by soxlhlet, evaluated in vitro tests on human tumor cells, showed potential and selective antitumor activities for certain cell lines. In addition, other secondary metabolites than violacein may be related with antitumor activity.
42

Atividade biorremediadora de Chromobacterium violaceum a metais pesados em ambientes aqu?ticos no semi?rido brasileiro: a??es para vigil?ncia ambiental e educa??o em sa?de / The activity of Chromobacterium violaceum in bioremediation of heavy metals in aquatic environment in brazilian semiarid: actions for monitoring environmental and health education

Alencar, Feliphe Lacerda Souza de 28 January 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-27T00:18:43Z No. of bitstreams: 1 FelipheLacerdaSouzaDeAlencar_DISSERT.pdf: 4823530 bytes, checksum: b4a668d3c4f491b90de30b674816113d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-09-01T22:58:50Z (GMT) No. of bitstreams: 1 FelipheLacerdaSouzaDeAlencar_DISSERT.pdf: 4823530 bytes, checksum: b4a668d3c4f491b90de30b674816113d (MD5) / Made available in DSpace on 2016-09-01T22:58:50Z (GMT). No. of bitstreams: 1 FelipheLacerdaSouzaDeAlencar_DISSERT.pdf: 4823530 bytes, checksum: b4a668d3c4f491b90de30b674816113d (MD5) Previous issue date: 2016-01-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A baixa qualidade h?drica no semi?rido brasileiro, em grande parte associa-se a a??o antr?pica, tal como o lan?amento de res?duos met?licos oriundos da ind?stria minerada. O presente estudo objetiva comparar e discutir a evolu??o das pesquisas realizadas em ?mbito mundial, as quais fizeram uso do potencial biorremediador da Chromobacterium violaceum a metais pesados; compreender a capacidade biorremediadora e avaliar os padr?es fenot?picos de resist?ncia em cepas selvagens e padr?es (ATCC 12472) de C. violaceum diante dos metais pesados, Ferro, Zinco e Mangan?s, em diferentes concentra??es e intera??es met?licas; analisar os par?metros f?sico-qu?micos e microbiol?gicos do reservat?rio Engenheiro Armando Ribeiro Gon?alves, situado do munic?pio de Jucurutu (regi?o semi?rida do Rio Grande do Norte - RN); verificar a abordagem da tem?tica biorremedia??o em livros did?ticos do ensino fundamental e m?dio indicados pelo PNLD 2014 e 2012, respectivamente, assim como desenvolver um produto did?tico direcionado ? contextualiza??o da interface conhecimento t?cnico-cient?fico e meio ambiente. A revis?o sistem?tica foi limitada a trabalhos publicados entre 2001 e 2014, utilizando-se dos bancos de dados LILACS, PubMed e SciELO. A avalia??o da resist?ncia de C. violaceum aos metais pesados ocorreu em concentra??es decrescentes de Fe, Mn e Zn, durante intervalos de 24, 48 e 72 horas por planejamento fatorial completo 23; o isolamento e a identifica??o microbiol?gica foram realizados conforme metodologia preconizada pelo Standard Methods for Examinations of Water and Wastewater; a avalia??o da capacidade biorremediadora de C. violaceum por espectrofotometria de absor??o at?mica (EAA), enquanto que a an?lise das unidades de registro a partir da adapta??o da metodologia de an?lise de conte?do de Bardin (2004). A biolixivia??o foi a t?cnica mais discutida; o ouro o substrato biorremediado mais citado e a cianeta??o o mecanismo fenot?pico prevalente. Mecanismos gen?ticos foram citados em 29,4% das publica??es e entre as prote?nas transcritas por C. violaceum 18,3% eram ditas hipot?ticas. Ambas as cepas de C. violaceum apresentaram resist?ncia aos metais testes em diferentes escalas de concentra??es, intera??es e intervalos de exposi??o. No entanto aquelas selvagens apresentaram uma resposta de fase aguda mais eficiente comparadas ?s padr?es, sobretudo para as concentra??es de 80 a 480 g/100ml x 10-3. A an?lise f?sico-qu?mica da ?gua revelou par?metros aceit?veis, conforme a resolu??o vigente, exceto para o ponto 5, no que tange a an?lise do pH, nesse ponto ocorreu o isolamento da C. violaceum, cuja capacidade biorremediadora aos elementos Fe, Mn e Zn mostrou-se mais eficiente quanto ?s cepas ATCC. Todos os livros did?ticos analisados, embora tenham sido recomendados pelo PNLD, apresentaram car?ncias quanto ? tem?tica biorremedia??o, fazendo-se necess?rio o desenvolvimento de materiais did?ticos que visem suprir tal abordagem. Os dados avaliados demonstram a fundamental import?ncia da C. violaceum como microorganismo biorremediador de metais pesados e evidencia a import?ncia do monitoramento ambiental, desenvolvimento e aplica??o da biorremedia??o em ambientes impactados, bem como destaca a necessidade da reformula??o da interface educa??o ambiental e biotecnologia, com a finalidade de possibilitar ao docente e ao estudante de ensino m?dio e fundamental uma reflex?o mais cr?tica sobre as rela??es que envolvem a polui??o ambiental e as poss?veis ferramentas mitigadoras dessa problem?tica. / The low water quality in the Brazilian Semiarid, in the most of cases is associated to human activities, such as the release of metallic waste from the mined industry. This study aims to compare and discuss the research evolution performed worldwide, which made use of the potential of C. violaceum for bioremediation of heavy metals; understand the bioremediation and phenotypic resistance patterns in wild and Standard strains (ATCC 12472) of heavy metals, iron (Fe), zinc (Zn) and manganese (Mn), in differents responce time, concentrations and metal interactions; evaluate the physicochemical and microbiological parameters in Engenheiro Armando Ribeiro Gon?alves reservoir, located in the county of Jucurutu (semiarid region of Rio Grande do Norte - RN); analyze the approach of the subject bioremediation in textbooks from elementary and high school appointed by 2014 and 2012 PNLD, respectively, as well as developing an educational product targeted to approaching the technical and scientific knowledge and the environment interface. The systematic review was limited to research published between 2001 to 2015, using LILACS, PubMed, and SciELO databases. The evaluation of C. violaceum resistance for heavy metals occurred in decreasing concentrations of Fe, Zn and Mn, at intervals of 24, 48 and 72 hours by a full factorial design 23; the isolation and microbiological identification were performed according to the methodology recommended by the Standard Methods for Examinations of Water and Wastewater; the evaluation the use of the potential of C. violaceum for bioremediation of heavy metals was performed by atomic absorption spectrophotometry (AAS), while the analysis of the reporting units was carried out from the adaptation of Bardin content analysis methodology (2004). The systematic survey showed that bioleaching technique was further discussed; gold was the bioremediated substrate most mentioned, and cyanidation was the prevalent phenotypic mechanism. Genetic mechanisms were mentioned in 29.4% of the publications, and among proteins transcribed by C. violaceum 18.3% were hypothetical. Whereas experimental data indicated that both strains of C. violaceum showed resistance to the metals tests on different scales concentrations, interactions and exposure intervals (p<10-5). However that wild showed a more efficient acute phase response compared to the standard, especially for metal concentrations from 80 to 480 g/100 mL x 10-3. The physicochemical water analysis revealed acceptable parameters as the current resolution, except for point five, as regards the analysis of pH, on this point was the isolation of C. violaceum, whose the use in bioremediation of Fe, Zn and Mn showed more efficient as the ATCC strain (p<10-5). Finally, the educational axis directed to the analysis of the textbooks showed that all of them, although they were recommended by PNLD, showed shortcomings regarding the subject bioremediation, making it necessary to develop educational materials aiming at to supply such an approach. The evaluated data demonstrated the fundamental importance of C. violaceum in bioremediation of heavy metals and highlights the importance of environmental monitoring, development and application of bioremediation in impacted environments and emphasizes the need to reworking the environmental education and biotechnology interface, in order to enable the teacher and high school and fundamental students to a critical reflection about the relationships involving environmental pollution and possible mitigation tools of this problem.
43

Análise da diversidade genética por MLSA e avaliação da atividade antitumoral de linhagens de Chromobacterium sp. / Genetic diversity analysis by MLSA and antitumoral activity evaluation of Chromobacterium sp. strains.

Cláudia Beatriz Afonso de Menezes 22 January 2009 (has links)
A diversidade genética dos isolados de Chromobacterium sp. foi avaliada por Multilocus sequence analysis com base nas análises dos genes conservados rpoA, lepA, gyrB, fusA e rRNA 16S. A análise do gene rRNA 16S e MLSA agrupou os isolados no gênero Chromobacterium, entretanto, cinco dos isolados estão distantes filogeneticamente das linhagens tipo, C. violaceum e C. subtsugae, sugerindo duas novas espécies. Os extratos brutos, obtidos por soxhlet, dos isolados de Chromobacterium sp., testados em ensaios in vitro em células tumorais humanas, apresentaram atividades antitumorais potenciais e seletivas para determinadas linhagens celulares. Os extratos brutos e frações foram analisados por HPLC-DAD para avaliação da presença ou ausência da violaceína. Além disso, outros metábólitos secundários que não a violaceína podem estar relacionados à atividade antitumoral. / The genetic diversity of strains of Chromobacterium sp was evaluated by Multilocus sequence analysis (MLSA) based on the analysis of conserved genes rpoA, recA, lepA, gyrB, fusA and rRNA 16S. The analysis of 16S ribosomal RNA gene grouped all isolates in the genus Chromobacterium, however, the five isolates are phylogenetically distant of type strain C. violaceum and C. subtsugae, suggesting new species. The crude extracts of the isolates from Chromobacterium sp., obtained by soxlhlet, evaluated in vitro tests on human tumor cells, showed potential and selective antitumor activities for certain cell lines. In addition, other secondary metabolites than violacein may be related with antitumor activity.

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