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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

Evaluating the Motivations, Knowledge, and Efficacy of Participants in Environmental Health Citizen Science Projects

Sandhaus, Shana Alysse, Sandhaus, Shana Alysse January 2017 (has links)
Environmental research is increasingly using citizen scientists in many aspects of projects, such as data collection and question design. To date, only a limited number of co-created citizen science projects where community members are involved in most or all steps of the scientific process have been completed, and few comparing community engagement methods and efficacy and learning outcomes across demo- and geographic data. This study compares two citizen science programs, evaluating what motivates citizen scientists to participate in environmental health research and whether participation affects scientific knowledge and environmental behavior and efficacy. Participants in the Gardenroots: A Citizen Science Garden Project completed sample collection training and submitted soil, water, vegetable, and dust samples for analysis and received their environmental monitoring results. In the Facilitating Community Action to Address Climate Change and Build Resiliency in Southern Metropolitan Tucson project, Spanish speaking community members of South Tucson underwent training in climate change and environmental quality and sample collection, and worked with families in the South Tucson community, collecting soil and water samples and providing environmental health education. For both projects, participants completed a pre- and post-survey with a variety of qualitative and quantitative questions. These survey instruments were used to evaluate differences in environmental self-efficacy and motivations. In addition, select Gardenroots participants were involved in focus groups and semi-structured interviews to understand and gauge changes in knowledge and to further explore changes in motivation and self-efficacy. The participants were primarily internally motivated and saw increases in both efficacy and knowledge as a result of participation in the program. This information is critical to moving citizen science efforts forward and determining whether such projects: 1) co-produce environmental monitoring, exposure assessment, and risk data in a form that will be directly relevant to the participant's lives, 2) increase the community’s involvement in environmental decision-making, and 3) improve environmental health education and literacy in underserved communities.
2

Região promotora e codificadora no gene HLA-E estrutura, variabilidade e haplótipos /

Ramalho, Jaqueline January 2017 (has links)
Orientador: Erick da Cruz Castelli / Resumo: Os genes do Complexo Principal de Histocompatibilidade (MHC) codificam moléculas envolvidas com a regulação do sistema imune, participando do reconhecimento do que é próprio ou estranho ao indivíduo. O gene HLA-E, parte do MHC, é caracterizado por apresentar baixa, porém, ampla expressão pelos tecidos do corpo. O HLA-E é extremamente conservado e um dos menos polimórficos entre os genes HLA de classe I. A principal função da molécula HLA-E está relacionada ao mecanismo de imunovigilância, através da interação com receptores de células Natural Killer e linfócitos T. Pontos de variação nas regiões regulatórias e codificadora de HLA-E podem alterar sua função através da modificação da expressão gênica ou estrutura da molécula codificada, influenciando a interação com peptídeos e receptores. O presente trabalho propôs a avaliação da variabilidade do segmento estendido do gene HLA-E, incluindo promotor e íntrons, e estrutura de haplótipos por meio de sequenciamento de nova geração ou sequenciamento massivo paralelo. A metodologia foi aplicada para avaliação da variabilidade de 420 amostras do Estado de São Paulo. Considerando um segmento de mais de 7kb, o gene HLA-E mostrou-se conservado, apresentando poucas sequências diferentes e frequentes. Ao todo, 63 pontos de variação foram encontrados e caracterizados em 75 haplótipos estendidos. Foram encontrados 37 haplótipos de região promotora, porém apenas 10 apresentam frequência superior a 1%. Para a região codificadora, foram encont... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Major Histocompatibility Complex (MHC) genes encode molecules involved mainly in recognition of self and non self antigens. The HLA-E gene is characterized by low but wide expression among tissues. Thus far, HLA-E is considered a conserved gene and one of the least polymorphic class I HLA genes. The main HLA-E function is related to immune surveillance by the interaction with natural killer cell receptors and T lymphocytes. Variable sites within the HLA-E regulatory and coding segments may influence gene function by modifying its expression pattern or encoded molecule, thus, influencing its interaction with receptors and the peptide. Here we propose an approach to evaluate de complete HLA-E variability, including promoter and introns segments, and the evaluation of the HLA-E haplotype structure by using massively parallel sequencing, or next-generation sequencing. The methodology was applied to survey the variability of a very admixed population such as Brazilians counting 420 samples of São Paulo State. Considering a segment of about 7kb, the HLA-E gene is indeed conserved with few different and frequent sequences. In general, 63 variable sites were detected, arranged 75 extended haplotypes. We found 37 promoter haplotypes, but only 10 presented a frequency greater that 1%. For the coding region, 27 haplotypes were detected, with 15 representing new HLA-E alleles. Nevertheless, the HLA-E conding alleles did encode mainly two different full-length molecules, known as alle... (Complete abstract click electronic access below) / Mestre
3

Promotoras and the Rhetorical Economies of Public Health: Deterritorializations of Medical Discourse and Practice

Hickman, Amy Christine January 2016 (has links)
In order to address the effects of unequal relations of power inherent in expert medical knowledge and practice that contribute to health inequities, this project defines and instantiates the concept of rhetorical economies in public health through a case study of promotora practices. As everyday experts, promotoras support medically underserved communities through health education and counseling. This project defines rhetorical economies of public health as those practices and processes which deterritorialize medical expertise in order to produce and distribute new knowledge economies related to bodies, health, and disease across everyday and expert communities. This participatory research is shaped by a community partnership with a promotora at work in public health settings. Historical analysis of the emergence of biomedical perception provides the context for a feminist rhetorical, decolonial, and critical discourse analyses of public health messaging as well as of this promotora's work stories and pedagogies. This project draws from Chela Sandoval's (2000) articulation of "differential consciousness" to identify processes where everyday and embodied practice differentially engage dominant medical discourse in order to re/appropriate, subvert, and transform "spaces of power" in medical contexts. Rhetorical economies are the means through which these transformations are possible. Narrative and rhetorical analysis of a promotora's work stories and pedagogies reveal how neoliberal and racialized medical discourse reproduce political and economic marginalizations while reinscribing medicalized understandings of the body, health and disease. Using the framework afforded by González, Moll, & Amanti's (2005) "funds of knowledge" approach, this project illuminates how rhetorical economies function to recenter community ways of knowing in order to decolonize biomedical epistemologies and practices. This project provides the foundation for future research in how rhetorical economies act to re/appropriate dominant discourses and advance transformational change. Grounded in medical, feminist, and decolonial rhetorics, this project it will find application across the disciplines, including education, rhetorical studies, cultural studies, medical anthropology, medical humanities, community action research, disability studies, health communication studies, and public health.
4

Líderes Comunitarias: Evaluation of Community Workshops on Domestic Violence

Macias, Rosemarie L 17 December 2015 (has links)
Domestic violence (DV) affects communities across a variety of nations and cultures, at significant physical, psychological, and economic costs to families. In the United States Latino families affected by DV often face unique challenges influenced by changing ecologies and personal as well as political histories. Peer-led workshops are one way for communities to disseminate information about social issues like DV in a culturally relevant manner, and they have the potential to promote capacity for addressing DV within communities. The impact of peer-led DV was examined using an embedded mixed-method design, where participant feedback collected throughout the study served to enhance the nonequivalent control group survey portion of the study. It was hypothesized that sense of community would moderate the relationship between workshop participation and capacity measures of knowledge, communication, and identification with Latina community leaders. Data screening and linear regression found no effects of workshop participation for knowledge and communication. A linear regression supported the hypothesized workshop by sense of community interaction effect, where individuals with higher sense of community were more likely to connect with workshop leaders in the workshop condition. Themes that emerged from the analysis of qualitative data from individual questionnaires, researcher notes, and a group interview were: (1) connection to the larger community organization, (2) family communication about domestic violence, (3) interest in support for Latino youth and (4) community leader’s testimonies of their own experiences of violence. Together, quantitative and qualitative findings lend weight to the notion that peer interventionists can establish meaningful connections and trust with community members based on their own lived experiences. Further research is needed to link this strength in a peer-led DV program to gains in capacity domains like knowledge. Overall, the results of this study extend research on cultural specific DV community programs and provide recommendations for community organizations seeking to evaluate community-based programs.
5

The Role of Social Capital in a Community Health Worker Model for Grassroots Advocacy

Jacobs, Laurel January 2012 (has links)
The social determinants of health continue to impact health disparities among communities living along the U.S.-Mexico border. Because community health workers (CHWs) are recognized for promoting a variety of positive patient-centered health outcomes in their roles as educators and health system navigators, recent inquiry has focused on the role of the CHW in facilitating community-level changes through grassroots advocacy to impact the social determinants of health. Social capital theory, which posits that participation in groups has positive consequences for individuals and the community, is a useful lens through which CHW effectiveness in grassroots advocacy can be measured and replicated. Using quantitative and qualitative methods, this study investigated the social capital characteristics of fifteen CHWs working in border communities who were trained in grassroots advocacy. Participating CHWs reported high baseline levels of social capital, which was assessed using a social capital questionnaire. After one year of engagement in grassroots advocacy, participating CHWs reported statistically significant increases in one measure of bridging social capital (community engagement) and one measure of linking social capita (participation with political/civic leaders). Qualitative interviews with each CHW further explored the role of social capital in their grassroots advocacy, resulting in a social capital model elucidating six activities of CHW-driven grassroots advocacy. The mixed methods results provide measures for assessing CHWs' social capital in their traditional roles and as grassroots advocates, as well as a framework for understanding how CHWs use their social capital to take grassroots action addressing the social determinants of health.
6

A escola como promotora da saúde: mobilização para melhores condições de saneamento básico / The school as a promoter of health: mobilization for better sanitation

Ribas, Maria Aparecida Pimentel Toloza 19 October 2016 (has links)
O saneamento é uma questão essencial para a qualidade de vida, para condições ambientais salubres, entre outros aspectos. O reconhecimento do saneamento como direito social diante da essencialidade à vida humana e à proteção ambiental ainda não foi contemplado dignamente. A pesquisa tem como objetivo investigar a viabilidade da escola tornar-se Promotora da Saúde implementando práticas sócioeducativas nos ambientes escolar e comunitário visando alcançar melhores condições de saneamento básico com mobilização social. A proposta adota a metodologia da pesquisa-ação com a estratégia da pesquisa social, atendendo os aspectos de interação e de investigação não se limitando a uma forma de ação, mas aumentando o conhecimento do pesquisador e dos atores envolvidos. Para tratar os dados de uma das atividades se utiliza o processo de análise de conteúdo. A pesquisa trata da Promoção da Saúde, da temática escola, do complexo saneamento e recursos hídricos; da mobilização, controle social e aprendizagem social. Definida a bacia hidrográfica do ribeirão da Vargem do Salto em Ibiúna/SP, para desenvolver as atividades previstas na pesquisa onde estão localizadas escolas municipais dos bairros Vargem do Salto, Lageado, Saltinho, Salto e Samano. Há um diálogo estabelecido entre a pesquisa e documentos oficiais legais para fundamentação teórica; e também sustentado pelo pensamento de Paulo Freire, John Dewey, Pedro Roberto Jacobi, Michael Apple, Moacir Gadotti, Leonardo Boff, Henry Giroux, Edgar Morin e Michel Thiollent. Promoção da Saúde definida como o processo de capacitação da comunidade para atuar na melhoria da sua qualidade de vida e saúde, inclui uma maior participação no controle deste processo e a escola pode ser um espaço para se concretizar as ações da Promoção da Saúde, proporcionando a mobilização, participação, o controle social e aprendizagem social. A síntese analítica adota o percurso metodológico de forma cronológica para apresentação dos resultados. Constata-se a função social da escola que adotando os princípios da Escola Promotora da Saúde adquire potencial para gerar processos que fortalecem a convivência, a participação, o diálogo permanente das pessoas e a compreensão consciente da sociedade em que vivem e a possibilidade de efetiva transformação. / Sanitation is essential to quality of life, healthy environmental conditions, among other things. The recognition of sanitation as a social right in light of its essentiality to human life and to environmental protection has not been contemplated in a dignified manner. This research aims to investigate the viability for the school to become a Promoter of Health by implementing socio-educational practices in the school and community environments in order to achieve better conditions of sanitation with social mobilization. The proposal adopts the methodology of research-action with the strategyof social research, taking into account the aspects of interaction and research, not limited to one form of action, but increasing the knowledge of the researcher and all involved. To process the data of one of the activities the content analysis process was used. The research deals with the Promotion of Health, the topic of the school, the sanitation and water resources complex; the mobilization, social control and social learning. The basin of the stream in Vargem do Salto in Ibiúna, SP, was established for the activities set in the survey to be developed, locality where municipal schools of Vargem do Salto, Lageado, Saltinho, Salto and Samanoare located. There is a dialogue between the research and the legal official documents for theoretical foundation; sustained by the points of view from Paulo Freire, John Dewey, Pedro Roberto Jacobi, Michael Apple, MoacirGadotti, Leonardo Boff, Henry Giroux, Edgar Morin and Michel Thiollent. Health promotion, defined as the process of empowerment of the community to work on improving their quality of life and health, includes a greater participation in the control of this process. The school can be a place to achieve the actions of Health Promotion, providing the mobilization, participation, social control and social learning. The analytical overview adopts a methodological path in a chronological way to present the results. It is noted that the schools social function that, adopting the principles of the School as a Health Promoter, gains potential to generate processes that strengthen coexistence, participation, permanent dialogue and the conscious understanding of the community in which they live and the possibility of effective transformation.
7

A escola como promotora da saúde: mobilização para melhores condições de saneamento básico / The school as a promoter of health: mobilization for better sanitation

Maria Aparecida Pimentel Toloza Ribas 19 October 2016 (has links)
O saneamento é uma questão essencial para a qualidade de vida, para condições ambientais salubres, entre outros aspectos. O reconhecimento do saneamento como direito social diante da essencialidade à vida humana e à proteção ambiental ainda não foi contemplado dignamente. A pesquisa tem como objetivo investigar a viabilidade da escola tornar-se Promotora da Saúde implementando práticas sócioeducativas nos ambientes escolar e comunitário visando alcançar melhores condições de saneamento básico com mobilização social. A proposta adota a metodologia da pesquisa-ação com a estratégia da pesquisa social, atendendo os aspectos de interação e de investigação não se limitando a uma forma de ação, mas aumentando o conhecimento do pesquisador e dos atores envolvidos. Para tratar os dados de uma das atividades se utiliza o processo de análise de conteúdo. A pesquisa trata da Promoção da Saúde, da temática escola, do complexo saneamento e recursos hídricos; da mobilização, controle social e aprendizagem social. Definida a bacia hidrográfica do ribeirão da Vargem do Salto em Ibiúna/SP, para desenvolver as atividades previstas na pesquisa onde estão localizadas escolas municipais dos bairros Vargem do Salto, Lageado, Saltinho, Salto e Samano. Há um diálogo estabelecido entre a pesquisa e documentos oficiais legais para fundamentação teórica; e também sustentado pelo pensamento de Paulo Freire, John Dewey, Pedro Roberto Jacobi, Michael Apple, Moacir Gadotti, Leonardo Boff, Henry Giroux, Edgar Morin e Michel Thiollent. Promoção da Saúde definida como o processo de capacitação da comunidade para atuar na melhoria da sua qualidade de vida e saúde, inclui uma maior participação no controle deste processo e a escola pode ser um espaço para se concretizar as ações da Promoção da Saúde, proporcionando a mobilização, participação, o controle social e aprendizagem social. A síntese analítica adota o percurso metodológico de forma cronológica para apresentação dos resultados. Constata-se a função social da escola que adotando os princípios da Escola Promotora da Saúde adquire potencial para gerar processos que fortalecem a convivência, a participação, o diálogo permanente das pessoas e a compreensão consciente da sociedade em que vivem e a possibilidade de efetiva transformação. / Sanitation is essential to quality of life, healthy environmental conditions, among other things. The recognition of sanitation as a social right in light of its essentiality to human life and to environmental protection has not been contemplated in a dignified manner. This research aims to investigate the viability for the school to become a Promoter of Health by implementing socio-educational practices in the school and community environments in order to achieve better conditions of sanitation with social mobilization. The proposal adopts the methodology of research-action with the strategyof social research, taking into account the aspects of interaction and research, not limited to one form of action, but increasing the knowledge of the researcher and all involved. To process the data of one of the activities the content analysis process was used. The research deals with the Promotion of Health, the topic of the school, the sanitation and water resources complex; the mobilization, social control and social learning. The basin of the stream in Vargem do Salto in Ibiúna, SP, was established for the activities set in the survey to be developed, locality where municipal schools of Vargem do Salto, Lageado, Saltinho, Salto and Samanoare located. There is a dialogue between the research and the legal official documents for theoretical foundation; sustained by the points of view from Paulo Freire, John Dewey, Pedro Roberto Jacobi, Michael Apple, MoacirGadotti, Leonardo Boff, Henry Giroux, Edgar Morin and Michel Thiollent. Health promotion, defined as the process of empowerment of the community to work on improving their quality of life and health, includes a greater participation in the control of this process. The school can be a place to achieve the actions of Health Promotion, providing the mobilization, participation, social control and social learning. The analytical overview adopts a methodological path in a chronological way to present the results. It is noted that the schools social function that, adopting the principles of the School as a Health Promoter, gains potential to generate processes that strengthen coexistence, participation, permanent dialogue and the conscious understanding of the community in which they live and the possibility of effective transformation.
8

La cultura de salud en las aulas de educación primaria y la incorporación de la escuela promotora de la salud a la salud escolar en España

Davó-Blanes, M. Carmen 09 June 2009 (has links)
Este proyecto ha recibido financiación de la Escuela Valenciana de Estudios para la Salud en la convocatoria de 2007 con referencia: 044/2006.
9

Cultivo de Haematococcus pluvialis sob condições de estresse e em consórcio microbiano visando obter maior rendimento de astaxantina

Nunes, Moira [UNESP] 27 October 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-10-27Bitstream added on 2014-06-13T20:24:21Z : No. of bitstreams: 1 nunes_m_dr_jabo.pdf: 789915 bytes, checksum: d33780e723c4af1036139660c9582f18 (MD5) Bitstreams deleted on 2016-10-27T11:27:29Z: 000681810.pdf,. Added 1 bitstream(s) on 2016-10-27T11:28:04Z : No. of bitstreams: 1 000681810.pdf: 562297 bytes, checksum: 2a5bb2ece78e1bfaa1bd6aca60814546 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A microalga Haematococcus pluvialis é conhecida como o microrganismo que apresenta maior rendimento final de astaxantina em sua biomassa, quando submetida a fatores de estresse celular eficientes. Contudo ainda apresenta uma característica de crescimento desfavorável quando comparada a outras espécies de microalgas cultivadas em escala comercial, visto que possui uma taxa de crescimento intrínseca, resultando em baixa densidade celular ao final dos cultivos. Assim, o rendimento final do pigmento é relativamente baixo. Neste sentido, este estudo teve por objetivo avaliar a resposta de Haematococcus pluvialis ao processo de indução à carotenogênese por meio de estresse luminoso e nutricional, e promover o aumento de biomassa vegetativa da microalga através da adição da rizobactéria promotora de crescimento em plantas, Azospirillum brasilense V6, estirpe produtora do fito hormônio AIA (ácido indol – acético), em cultivos estanques, visando obter maior rendimento final de astaxantina. O trabalho foi dividido em duas fases. Primeiramente, no cultivo referente ao controle (contendo apenas H. pluvialis) foram aplicadas duas combinações de fatores de estresse celular para indução a síntese de astaxantina pela microalga, visando a escolha do método de estresse a ser aplicado na fase seguinte. As células de H. pluvialis foram submetidas ao estresse por alta intensidade luminosa (350 μmol photons m-2 s-1) ou ao mesmo estresse luminoso aliado a suplementação com CO2 (4%) na aeração fornecida na fase exponencial de crescimento. Avaliou-se, entre outros fatores de resposta celular, a concentração final de astaxantina na biomassa após 10 dias de estresse. As concentrações do pigmento foram 4,15 e 17,66 mg g-1, respectivamente, para as culturas submetidas ao estresse luminoso e para... / The microalgae Haematococcus pluvialis is known as the microorganism that has a highest final yield of astaxanthin in its biomass, when induced by efficient stress factors. However, still presents a characteristic of unfavorable growth when compared to other species of microalgae grown on a commercial scale, once it has an intrinsic growth rate that provides low cell density in the culture. Thus, the final yield of the pigment is relatively low. Thus, this study aimed to evaluate the response of Haematococcus pluvialis submitted to carotenogenesis induction process through light and nutrient stress, and promotion of vegetative microalgae biomass increase through the addition of the growth promoter bacteria in plants, Azospirillum brasilense V6, a strain that produce the phyto hormone IAA (indole - acetic acid). The experiments were performed in “batch” systems, aiming to obtain higher final yield of astaxanthin. The work was divided into two phases. First, to the control (containing only H. pluvialis) it was applied two combinations of stress factors to induce cellular synthesis of astaxanthin by the microalgae, to define the method of stress to be applied in the next phase. The cells of H. pluvialis were submitted to stress by high light intensity (seven times the original) or the same light stress combined with CO2 supplementation (4%) in the aeration provided in the exponential growth phase. We evaluated, among other factors of cellular response, the final concentration of astaxanthin in the biomass after 10 days of stress. The pigment concentrations were 4.15 and 17.66 mg g-1, respectively, for cultures submitted to light stress and to those who received the same light stress add with the increase of C / N ratio in the culture medium. So, for the next experimental phase, the combination... (Complete abstract click electronic access below)
10

Burkholderia sp. cadmium tolerance mechanism and its influence in phytoremediation / Mecanismos de tolerância ao cádmio em Burkholderia sp. e sua aplicação na fitorremediação

Ribeiro, Manuella Nóbrega Dourado 22 November 2013 (has links)
Soils have been contaminated with cadmium (Cd) by the use of fertilizers, calcareous, pesticides and industrial and/or domestic effluents. It can be leached to groundwater, as well as be taken up by plants potentially leading to reduce growth and yield. It causes different damages to the cell, generating oxidative stress which is responsible for its toxicity, affecting all living organism. A balance in the redox state of the cell to maintain cellular integrity and metabolism is essential for organism tolerance. Thus, the antioxidant response of bacteria exposed to Cd was studied to understand the tolerance mechanism, and be able to develop a methodology to bioremediate contaminated soils. MDA and hydrogen peroxide contents and different enzymes activity of antioxidant system (SOD, CAT, GR and GST) of two strains from Burkholderia genus, one from a soil contaminated with Cd in high concentrations (strain SCMS54) and the other from soil without Cd (strain SNMS32) in two exposure time (5 and 12 h), were analyzed. Stress measurement (MDA and hydrogen peroxide content) and antioxidant enzyme activities (SOD, CAT, GR and GST) increased in almost all treatments in the presence of Cd. These results also indicate that strain SCMS54 (isolated from Cd contaminated soil) presents a higher metabolic diversity and plasticity due the expression of more isoforms of the enzymes SOD, CAT and GR. The strain also accumulates 50% more Cd. We also analyzed the response to Ni of these two strain, observing a similar response to Cd, except for GST enzyme expression, which in strain SCMS54 this enzyme was induced in the presence of Ni, indicating that this enzyme can be essential on Ni tolerance. After that, the strain isolated from Cd contaminated soil (SCMS54) was selected to proceed the studies to evaluate the benefits of tolerant microorganism-tomato plant interaction. The use of plants to remove heavy metals from contaminated soilhas less impact and a lower cost. Soil microorganisms can be able to solubilize or mobilize soil metals acting also as bioremediator. Besides the high tolerance to Cd, the strain SCMS54 can produce indole-acetic acid (IAA), solubilize inorganic phosphate and produce siderophore, revealing its potential in plantmicroorganism mutual and beneficial interaction. When interacting with tomato plants exposed to Cd, this bacterium led to decrease in plant peroxide concentration and chlorosis levels, promoted relative plant growth and reduced the root absorption of Cd resulting in an increase in plant tolerance to this highly toxic heavy metal. Indicating that inoculation of tomato plants with Burkholderia sp. SCMS54 promotes better growth when cultivated in the presence of Cd by a mechanism that appears to decrease Cd concentration in roots as a result of a bacterial-plant root beneficial interaction. / O cádmio (Cd) tem contaminado solos pelo uso de fertilizantes, calcário, agrotóxicos e resíduos industriais e/ou domésticos. Podendo ser lixiviado ao lençol freático ou absorvido pelas plantas,resultando na redução do crescimento e da produtividade. Esse metal afeta todos os organismos vivos e causa diferentes danos às células. A tolerância a esse metal se deve principalmente ao balanço do estado redox da célula para manter a integridade celular e metabolismo.Assim, foram isoladas bactérias de solo contaminado e não contaminado com Cd, selecionando isolados tolerantes a altas concentrações de diferentes metais (Cd, Ni e Zn), em seguida, foi observado a resposta do sistema antioxidante da bactéria na presença do Cd, a fim de auxiliar no desenvolvimento de metodologias para biorremediar solos contaminados. Foi quantificado MDA e peróxido de hidrogênio e a atividade de diferentes enzimas do sistema antioxidante (SOD, CAT, GR e GST) de duas estirpes do gênero Burkholderia tolerantes a todos os metais testados, uma isolada do solo contaminado com altas concentrações de Cd (estirpe SCMS54) e a outra do solo sem Cd (estirpe SNMS32) em dois tempos de exposição (5 e 12 h). Na estirpe SCMS54, as medidas de estresse (peroxidação lipídica e peróxido de hidrogênio) e a atividade das enzimas antioxidantes (SOD, CAT, GR e GST) da maioria dos tratamento com cádmio aumentaram, esta estirpe também expressa mais isoformas de SOD, CAT e GR, além de acumular 50% mais Cd. Esses resultados mostram que a estirpe SCMS54 (isolada do solo contaminado com Cd) apresenta uma maior diversidade metabólica e plasticidade. Foram analisadas também a resposta dessas duas estirpes ao Ni, observando uma resposta semelhante ao Cd, exceto na expressão da enzima GST, que no estirpe SCMS54 foi induzida na presença do Ni, indicando que essa enzima pode ser essencial na tolerância ao Ni. Portanto, a estirpe isoladado solo contaminado com Cd (SCMS54) foi selecionada para prosseguir os estudos e avaliar os benefícios da interação entre microrganismos tolerantes-plantas de tomate na fitorremediação. Essa técnica é usada remover para metais pesados do solo com um menor impacto e baixos custos. Os microrganismos do solo podem solubilizar e mobilizar metais do solo, atuando como biorremediador. Além da alta tolerância ao Cd, a estirpe SCMS54 produz ácido indol acético (AIA), solubiliza fosfato inorgânico e produz sideroforo, mostrando seu potencial na interação benéfica planta-microorganismo. Quando interagindo com as plantas de tomate expostas ao Cd, essa bactéria diminui a concentração de peróxido da planta e a clorose ocasionado pelo Cd,e reduz a absorção de Cd pela raiz resultando em um aumento da tolerância da planta ao metal pesado altamente tóxico. Assim, a inoculação de plantas de tomate com Burkholderia sp. SCMS54 promove crescimento da planta na presença de Cd, desencadeando um mecanismo que diminui a concentração de Cd nas raízes devido a essa interação benéfica bactéria-raiz da planta.

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