10 research outputs found

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Induced pluripotent stem cell for study and treatment of sickle cell anemia

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    A anemia falciforme (AF) é uma doença monogênica de elevada mortalidade e morbidade, que afeta milhões de pessoas em todo o mundo. Não há tratamento definitivo que seja amplo, eficaz e seguro para a AF, de forma que os tratamentos paliativos são os mais utilizados. O tratamento definitivo disponível é transplante alogênico de células-tronco hematopoiéticas, porém com várias complicações envolvidas. O estabelecimento de um modelo in vitro permite uma melhor compreensão de como a doença ocorre, além de permitir o desenvolvimento de novos testes e tratamentos mais eficazes contra a doença. Neste contexto, a tecnologia das células-tronco pluripotentes induzidas (iPSC), que surgiu em 2006, é uma ferramenta poderosa na pesquisa básica, na pesquisa da diferenciação de tecidos e no modelamento de doenças, e uma promessa para futuras aplicações clínicas, na descoberta e triagem de novas drogas mais eficazes e seguras, além da possibilidade de utilização na medicina regenerativa, na produção de células paciente-específicas para terapia celular. Este trabalho teve como objetivo obter um modelo de estudo e tratamento da AF utilizando iPSC. Para isso, vetores epissomais foram utilizados para a reprogramação de células mononucleares de sangue periférico para obter iPSC livres de integração. Estas células foram coletadas de pacientes tratados com o medicamento hidroxiureia e sem tratamento, para avaliação do impacto da droga na reprogramação. As linhagens de iPSC PBscd geradas foram caracterizadas quanto ao potencial pluripotente e de diferenciação. Todas as linhagens geradas se mostraram pluripotentes com potencial de auto renovação e potencial de formar células e tecidos dos 3 folhetos germinativos. O rastreamento dos vetores utilizados na reprogramação mostrou que as células estão livres após cerca de 10 passagens em média, e que eles não se integram espontaneamente nas células. As linhagens de iPSC foram diferenciadas em progenitores hematopoiéticos através da agregação forçada associada à indução com citocinas específicas e um cultivo em suspensão. Dessa forma, nós obtivemos um protocolo dinâmico e eficiente de produção de células CD34+CD45+ com poucos dias de indução. Foram realizados experimentos iniciais de padronização da metodologia de CRISPR, para que essa metodologia possa ser utilizada no futuro para a correção da mutação da AF no gene da ?- globin. Além disso, a reação padronizada para o rastreamento da mutação no gene da ?-globin poderá ser usado em experimentos futuros de edição gênica para avaliar a correção da mutação. Em resumo, oferecemos uma ferramenta valiosa para uma melhor compreensão de como a AF ocorre, além de tornar possível o desenvolvimento de drogas e tratamentos mais eficazes e de fornecer um melhor entendimento dos tratamentos amplamente utilizados, como a hidroxiureaSickle cell anemia (SCA) is a monogenic disease of high mortality and morbidity, that affects millions of people worldwide. There is no definitive treatment that is broad, effective and safe for SCA, so the palliative treatments are the most used. The definitive treatment available is the allogeneic transplantation of hematopoietic stem cells, but with several complications involved. The establishment of an in vitro model allows better understanding of how the disease occurs, besides allowing the development of more effective new tests and treatments against the disease. In this context, the induced pluripotent stem cell (iPSC) technology, that emerged in 2006, is a powerful tool for basic research, tissue differentiation research and disease modeling, and a promise for future clinical applications, to find and screen new, more effective and safe drugs, besides the possibility of use in regenerative medicine, in the production of patient-specific cells for cell therapy. This work aimed to obtain a model for study and treatment of SCA using iPSC. For this, episomal vectors were used for reprogramming peripheral blood mononuclear cells to obtain integration-free iPSC. This cells were collected from patients treated with hydroxyurea and without treatment, for evaluation of the impact of the drug in reprogramming. The generated iPSC PBscd lines were characterized for pluripotent and differentiation potential. All the generated lines were shown to be pluripotent with potential for self-renewal and to form cells and tissues of the 3 germ layers. Screening of the vectors used for reprogramming showed that they are absent after about 10 passages, and that they do not integrate spontaneously into the cells. The iPSC lines were differentiated into hematopoietic progenitors through forced aggregation associated with induction with specific cytokines and culture in cell suspension. Thus, we obtained a dynamic and efficient protocol of CD34+CD45+ cells production with a few days of induction. Initial standardization experiments of CRISPR methodology was performed, so that this methodology can be used in the future to correct the ?-globin chain mutation of SCA. Also, the standardized reaction for the screening of ?-globin chain mutation can be used in future gene-editing experiments to evaluate the mutation correction. In summary, we offer a valuable tool for a better understanding of how SCA occurs, in addition to make possible the development of more effective drugs and treatments and providing better understanding of widely used treatments, such hydroxyre

    Generation of human induced pluripotent stem (iPS) cell using lentiviral vector and determination of the lentiviral integration profile

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    As células iPS surgiram com a promessa de contornar as limitações das células-tronco embrionárias, como questões éticas, segurança, compatibilidade e disponibilidade. Essas células podem ser obtidas a partir de células somáticas de indivíduos normais ou de pacientes com doenças genéticas, fazendo destas uma importante ferramenta para o screening de drogas, modelos de doenças e testes toxicológicos. Grandes avanços ocorreram na reprogramação de células diferenciadas pela expressão forçada de fatores de transcrição (FT), principalmente, através de vetores lentivirais (VL), que proporcionam uma reprogramação eficiente. Entretanto, a inserção lentiviral no genoma humano e sua influência na reprogramação é pouco conhecida. Neste trabalho, avaliamos o perfil de inserção dos VL utilizados na geração de iPS. As iPS foram geradas e caracterizadas por nosso grupo a partir de fibroblastos humanos transduzidos com VL contendo 3 FT [SOX2, TCL-1A e C-MYC (célula TSM)], e de células mesenquimais derivadas de tecido adiposo com um vetor lentiviral policistrônico contendo 4 FT [OCT4, SOX2, KLF4 e C-MYC (iPS 4FT)]. Cinco colônias isoladas de cada iPS foram mapeadas e analisadas quanto aos sítios de inserção pela técnica de LM-PCR. O DNA genômico digerido foi amplificado com um primer específico para o LTR viral e outro para um linker sintético. Os produtos foram clonados, sequenciados, e analisados em bancos de dados para identificar similaridades com o genoma humano, entre outras análises. Na célula TSM, 176 sequências, obtidas com a técnica de LM-PCR, apresentaram identidade com o genoma humano, sendo que cerca de 50% ocorreram em regiões gênicas com 94% destas em introns. Já nas iPS 4FT, 251 sequências apresentaram identidade, com cerca de 45% atingindo genes, 92% destas em introns. As inserções distribuíram-se por todos os cromossomos, com preferência pelos cromossomos 16, 17 e 20 para a TSM e pelos cromossomos 11, 15 e 17 para a iPS 4FT. Analisamos a distância da inserção ao sítio de início de transcrição (TSS), e inserções próximas a ilhas CpG, que em geral correspondem a regiões regulatórias. A maior proporção de inserção ocorreu a partir de ±30Kb de distância desses sítios. Os sítios frágeis e as regiões repetitivas do genoma foram atingidas, mas com uma frequência baixa. Os resultados mostraram uma preferência de inserção lentiviral por regiões gênicas nas iPS, indicando a possível participação de proteínas como LEDGF/p75 na integração nas células estudadas. Este trabalho mostrou que o local da integração pode contribuir para a reprogramação e, apesar de possíveis efeitos negativos das integrações, estas as células iPS ainda são uma ferramenta importante para estudos in vitro. E identificar fatores que influenciem a seleção do sítio de inserção é importante para determinar regiões cromossômicas \"seguras\" para a integração, aumentando a segurança no uso clínico.The induced pluripotent stem (iPS) cells came with the promise of circumvent some of the limitations in the use of embryonic stem cells, like ethical issues, biological safety, immune compatibility and availability. This cells can be generated from somatic cells of normal individuals or from patients with some genetic disease, making then an important tool for drug screening, construction of disease models and toxicological trials. Great advances have happened in reprogramming differentiated cells through the forced exogenous expression of transcription factors (TF), mostly by lentiviral vectors (LV), which provide an efficient reprogramming. However, the lentiviral insertion in the human genome and its influence in reprogramming is not well known. In this work, we evaluate the insertion profile of LV used to generate human iPS cells. The iPS cells were generated, by our group, from human fibroblasts transduced by LV containing 3 TF [SOX2, TCL-1A and C-MYC (TSM reprogrammed cell)], and from mesenchymal cells derived from human adipose tissue transduced by a polycistronic LV containing 4 TF [OCT4, SOX2, KLF4 and C-MYC (iPS 4TF)]. Five isolated colonies of each iPS cell were mapped and analyzed for the insertion sites through LM-PCR technique. The digested genomic DNA was amplified with a primer for the viral LTR e another for a synthetic linker. The products were cloned, sequenced and analyzed in database to identify similarities with the human genome, among other analyzes. In TSM cell, 176 sequences, derived from the LM-PCR technique, presented identity with the human genome, and about 50% of those occurred in genic regions with 94% in introns. In iPS 4TF, 251 sequences showed identity, with about 45% reaching genes, 92% of these in introns. The insertions were distributed on all chromosomes, with preference for the 16, 17 and 20 for the TSM cell, and for the 11, 15 and 17 for the iPS 4TF. We analyzed the distance of the insertion from de transcription start site, and insertions near CpG islands, which, overall, correspond to regulatory regions. The highest proportion of insertion occurred starting ±30Kb distance from these sites. The fragile sites and the repetitive regions of the genome were also reached, but with low frequency. The results showed a preference of lentiviral insertion for genic regions in iPS, indicating the potential participation of proteins like LEDGF/p75 in integration in the cells of this work. This work shows that the integration site may contribute to the reprogramming, and, despite possible negative effects of integration, these iPS cells are still an important tool for in vitro studies. Identify factors that influence the selection of insertion site is important for determination of \"safe\" chromosomal regions for the integration, increasing the safe in clinical use

    Pluripotent Reprogramming of Fibroblasts by Lentiviralmediated Insertion of SOX2, C-MYC, and TCL-1A

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    Reprogramming of somatic cells to pluripotency promises to boost cellular therapy. Most instances of direct reprogramming have been achieved by forced expression of defined exogenous factors using multiple viral vectors. The most used 4 transcription factors, octamer-binding transcription factor 4 (OCT4), (sex determining region Y)-box 2 (SOX2), Kruppel-like factor 4 (KLF4), and v-myc myelocytomatosis viral oncogene homolog (C-MYC), can induce pluripotency in mouse and human fibroblasts. Here, we report that forced expression of a new combination of transcription factors (T-cell leukemia/lymphoma protein 1A [TCL-1A], C-MYC, and SOX2) is sufficient to promote the reprogramming of human fibroblasts into pluripotent cells. These 3-factor pluripotent cells are similar to human embryonic stem cells in morphology, in the ability to differentiate into cells of the 3 embryonic layers, and at the level of global gene expression. Induced pluripotent human cells generated by a combination of other factors will be of great help for the understanding of reprogramming pathways. This, in turn, will allow us to better control cell-fate and apply this knowledge to cell therapy.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Financiadora de Estudos e Projetos (FINEP), Brazi

    Induced Pluripotent Stem Cell for the Study and Treatment of Sickle Cell Anemia

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    Sickle cell anemia (SCA) is a monogenic disease of high mortality, affecting millions of people worldwide. There is no broad, effective, and safe definitive treatment for SCA, so the palliative treatments are the most used. The establishment of an in vitro model allows better understanding of how the disease occurs, besides allowing the development of more effective tests and treatments. In this context, iPSC technology is a powerful tool for basic research and disease modeling, and a promise for finding and screening more effective and safe drugs, besides the possibility of use in regenerative medicine. This work obtained a model for study and treatment of SCA using iPSC. Then, episomal vectors were used for reprogramming peripheral blood mononuclear cells to obtain integration-free iPSC. Cells were collected from patients treated with hydroxyurea and without treatment. The iPSCP Bscd lines were characterized for pluripotent and differentiation potential. The iPSC lines were differentiated into HSC, so that we obtained a dynamic and efficient protocol of CD34+CD45+ cells production. We offer a valuable tool for a better understanding of how SCA occurs, in addition to making possible the development of more effective drugs and treatments and providing better understanding of widely used treatments, such as hydroxyurea

    VIII Congresso Estadual Paulista sobre Formação de Educadores

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    O tema proposto para discussão durante o VIII Congresso Estadual Paulista sobre a Formação de Educadores – Modos de ser Educador: Artes e Técnicas – Ciências e Políticas envolve a busca de integração entre as diferentes dimensões que compõem a formação do profissional da educação. O trabalho e o sentido da intervenção social desse profissional se constituem em objeto em torno do qual as análises e interpretações vão recolher os fundamentos de debate sobre cultura como totalidade, incluindo: Artes e Técnicas – Ciências e Políticas. A dinâmica que caracteriza a formação de educadores requer a interpretaçãodesses fundamentos para o constante redimensionamento e definição dos objetivos visando aperfeiçoar o papel do profissional educador na sociedade. Por meio de discussões entrediferentes setores ligados à educação é que podem ser avaliados, preservados ou transformados os móveis que norteiam a formação do educador dentro de contextos culturais/sociais específicos, nos diversos campos, artes, técnicas, ciências e políticas. A disponibilidade de um espaço como o VIII Congresso Estadual Paulista sobre a Formação de Educadores para que estudiosos do tema - Educação - se congreguem e debatam a produção de conhecimento sob diversos ângulos, insere e qualifica esse evento como um processo de contribuição para o aprofundamento de estudos na área educacional. Os Congressos Estaduais Paulistas sobre a Formação de Educadores (CEPFE) vêm acontecendo desde 1990 e têm dedicado ênfase especial à formação de profissionais da educação, nos níveis de ensino fundamental, médio e universitário. Tal conformação do Congresso procura extrapolar questões próprias do padrão formal, para a abordagem de formação do profissional da educação embasada na crítica constante, capaz de dinamizar processos e resultados. Essa pretensão ressalta a importância do envolvimento de diferentes áreas do saber numa discussão sobre significados da produção de conhecimento. Daí poderão provir os resultados esperados a partir das atividades programadas para o VIII Congresso dentre os quais está esse caderno de resumos que ora apresentamos.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Núcleos de Ensino da Unesp: artigos 2008

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    Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
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