35 research outputs found

    As áreas naturais protegidas mais conhecidas pelos residentes na Ilha Terceira.

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    A CONSERVAÇÃO DA BIODIVERSIDADE é um objectivo central para a sobrevivência dos seres humanos no Planeta Terra. No entanto enfrentamos problemas e desafios complexos no que se refere à sua operacionalização. Como se conservam as espécies? Que espécies conservar primeiro? Que papel pode cada um de nós desempenhar na sua conservação? O declínio da riqueza e também da abundância de espécies – mesmo de espécies comuns – tem sido bem documentado nos últimos anos (ex. Borges, Gabriel & Fattorini, 2020), surgindo até a ideia de que a extinção de espécies a que assistimos marcaria o início de uma nova época – o Antropoceno, conceito proposto em 2000, e caracterizado pelo efeito significativo e duradouro das actividades humanas no planeta Terra (Crutzen & Stoermer, 2000; Mendes, 2020).info:eu-repo/semantics/publishedVersio

    FOXC2 controls adult lymphatic endothelial specialization, function, and gut lymphatic barrier preventing multiorgan failure.

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    The mechanisms maintaining adult lymphatic vascular specialization throughout life and their role in coordinating inter-organ communication to sustain homeostasis remain elusive. We report that inactivation of the mechanosensitive transcription factor Foxc2 in adult lymphatic endothelium leads to a stepwise intestine-to-lung systemic failure. Foxc2 loss compromised the gut epithelial barrier, promoted dysbiosis and bacterial translocation to peripheral lymph nodes, and increased circulating levels of purine metabolites and angiopoietin-2. Commensal microbiota depletion dampened systemic pro-inflammatory cytokine levels, corrected intestinal lymphatic dysfunction, and improved survival. Foxc2 loss skewed the specialization of lymphatic endothelial subsets, leading to populations with mixed, pro-fibrotic identities and to emergence of lymph node-like endothelial cells. Our study uncovers a cross-talk between lymphatic vascular function and commensal microbiota, provides single-cell atlas of lymphatic endothelial subtypes, and reveals organ-specific and systemic effects of dysfunctional lymphatics. These effects potentially contribute to the pathogenesis of diseases, such as inflammatory bowel disease, cancer, or lymphedema

    The Azorean Biodiversity Portal: an internet database for regional biodiversity outreach

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    Copyright © 2010 The Natural History Museum.There is a growing interest in academia to provide biodiversity data to both the scientific community and the public. We present an internet database of the terrestrial lichens, bryophytes, vascular plants, molluscs, arthropods, vertebrates and coastal invertebrates of the Azores archipelago (Portugal, North Atlantic): the Azorean Biodiversity Portal (ABP, http://www.azoresbioportal.angra.uac.pt/). This is a unique resource for fundamental research in systematics, biodiversity, education and conservation management. The ABP was based on a regional species database (ATLANTIS), comprised of grid-based spatial incidence information for c. 5000 species. Most of the data rely on a comprehensive literature survey (dating back to the 19th century) as well as unpublished records from recent field surveys in the Azores. The ABP disseminates the ATLANTIS database to the public, allowing universal, unrestricted access to much of its data. Complementarily, the ABP includes additional information of interest to the general public (e.g. literature on Macaronesian biodiversity) together with images from collections and/or live specimens for many species. In this contribution we explain the implementation of a regional biodiversity database, its architecture, achievements and outcomes, strengths and limitations; we further include a number of suggestions in order to implement similar initiatives

    Global Island Monitoring Scheme (GIMS) : a proposal for the long-term coordinated survey and monitoring of native island forest biota

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    Islands harbour evolutionary and ecologically unique biota, which are currently disproportionately threatened by a multitude of anthropogenic factors, including habitat loss, invasive species and climate change. Native forests on oceanic islands are important refugia for endemic species, many of which are rare and highly threatened. Long-term monitoring schemes for those biota and ecosystems are urgently needed: (i) to provide quantitative baselines for detecting changes within island ecosystems, (ii) to evaluate the effectiveness of conservation and management actions, and (iii) to identify general ecological patterns and processes using multiple island systems as repeated 'natural experiments'. In this contribution, we call for a Global Island Monitoring Scheme (GIMS) for monitoring the remaining native island forests, using bryophytes, vascular plants, selected groups of arthropods and vertebrates as model taxa. As a basis for the GIMS, we also present new, optimized monitoring protocols for bryophytes and arthropods that were developed based on former standardized inventory protocols. Effective inventorying and monitoring of native island forests will require: (i) permanent plots covering diverse ecological gradients (e.g. elevation, age of terrain, anthropogenic disturbance); (ii) a multiple-taxa approach that is based on standardized and replicable protocols; (iii) a common set of indicator taxa and community properties that are indicative of native island forests' welfare, building on, and harmonized with existing sampling and monitoring efforts; (iv) capacity building and training of local researchers, collaboration and continuous dialogue with local stakeholders; and (v) long-term commitment by funding agencies to maintain a global network of native island forest monitoring plots.Peer reviewe

    [Increased IL-4 production in response to virulent Mycobacterium tuberculosis in tuberculosis patients with advanced disease].

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    The study was designed to compare immune responses to Mycobacterium tuberculosis bacilli and antigens in healthy Portuguese subjects and pulmonary tuberculosis patients (TB), and to correlate immune status with clinical severity of tuberculosis disease. PBMC were cultured and stimulated with live and killed M. tuberculosis H37Rv and purified protein derivative (PPD) and lymphoproliferation and production of IFN-gamma and IL-5/IL-4 by these cultures were evaluated by the use of ELISA and multi-parameter flow cytometry. PBMC from 30 tuberculosis patients demonstrated significantly reduced amounts of proliferation and IFN-gamma when stimulated with live M. tuberculosis compared the control group. Of 15 tuberculosis patients tested for intracellular IL-4 following stimulation with M. tuberculosis, 7 showed greatly increased IL-4 production in CD8+ and gammadelta+ T cells. Tuberculosis patients demonstrated an increase of intracellular IL-4 after PBMC were stimulated with live M. tuberculosis in the CD4+ phenotype, but more notably in CD8+ and gammadelta TCR+ subsets. Increased production of IL-4 in tuberculosis patients was primarily in individuals with advanced involvement of lung parenchymal with high bacterial loads in sputum. These results suggest that an alteration in type 1 and type 2 cytokine balance can occur in patients with tuberculosis at an advanced clinical stage of disease

    Respostas Th1 e Th2 desencadeadas por Mycobacterium tuberculosis virulento em doentes com tuberculose pulmonar

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    RESUMO: Analisaram-se as respostas Th1 e Th2 desencadeadas por Mycobacterium tuberculosis virulento em doentes com tuberculose pulmonar (TP) e em dadores saudáveis vacinados pela BCG. Efectuaramse comparações entre a capacidade que as células T apresentavam para proliferar e para produzir IFN-γ e IL-5 em resposta aos derivados de proteíns purificada (PPD), M. tuberculosis H37Rv (Mtb), e M. tuberculosis H37Rv inactivado pelo calor (hk Mtb).Este estudo demoostrou que os individuos saudá-vels vacínados com BCG evidenciaram um máximo de proliferação e produção de IFN-γ em resposta ao painel de antigénios, e que Mtb vívo destencadeou uma resposta significativamente mais forte que a obtida pelo Mtb inactivado pelo calor. Embora os doentes com tuberculose pulmonary mostrassem respostas medias mais baxies de proliferação e produção de IFN-γ cm relação aos eontrolos saúdaveis, a resposta proliferativa ao PPD não foi significativamente reduzida, enquanto que a resposta ao Mtb e hk Mtb foram, significativas estatisticamitante. Em conclusão na tuberculose pulmonar a produção de IFN-γ pode estar reduzida sem um concomitante aumento de IL-5, confirmandose assim não existir uma mudança de resposta Th1 para Th2 na tuberculose pulmonar.REV PORT PNEUMOL 1998; IV (4):393-402 ABSTRACT: The contribution of Th1 and Th2 responses elicited by virulent Mycobacterium tuberculosis was investigated, in healthy BCG vaccinated individuals and pulmonary tuberculosis patients. Comparisons were made between the T cell capacity to proliferate, produce IFN-γ and IL-5 in response to the soluable antigen purified protein derivative (PPD), live M. tuberculosis H37Rv (Mtb) and heat killed M tuberculosis H37Rv (hk Mtb). These studies demonstrated that control individuals showed the strongest mean proliferative and IFN-γ responses towards the antigen antigen panel and Mth elicited a significantly stronger response than hk Mtb. Although, pulmonary tuberculosis patients showed lower mean proliferation and IFN-γ towards all the antigen when compared to that control group, proliferative responses to PPD were found not to be significantly reduced, while the reduction in the response to Mtb and hk Mtb preparations were statistically significant. In conclusion, in pulmonary tuberculose infection mean prodution of IFN-γ may be reduced but no concomitant increase in IL-5 production occurred. These data confirm that there is no switch from a Th1 response to a Th2 response in tuberculosis infection.REV PORT PNEUMOL 1998; IV (4): 393-402 Key-words: Cellular Immunity, Cytokines, Pulmonary tuberculoses, Th1 and Th2 responses, Palavaras-chave: Imunidade Celular, Citocinas, Tuberculose Pulmonar, respostas Th1 e Th

    Respostas das citocinas T 2 desencadeadas por Mycobacterium tuberculosis virulento nos doentes com tuberculose pulmonar em estado avançado

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    RESUMO: Avaliaram-se in vitro as respostas das citocinas Tipo 1 e Tipo 2 de dadores portugueses saudáveis vacinados à nascença com BCG, com Mantoux positivo (induraçãoâ¥5 mm) e de doentes com tuberculose pulmonar (TP). Foi efectuado o estudo por ELISA da produção de IFN-γ e IL-5 por Células Mononucleares do Sangue Periférico (CMSP) dos dadores após estimulação com M. tuberculosis e antigénio solúvel PPD. Foi confirmada a presença intracelular de IFN-γ e de IL-4 em subpopulações de células T por análise multiparamétrica, em citometria de fluxo. As CMSP dos doentes com tuberculose estimuladas com PPD e M. tuberculosis demonstraram uma diminuição na produção de IFN-γ sem aumento da produção de IL-5 em resposta ao painel de antigénios. Nos doentes com tuberculose observou-se uma frequência diminuída de IFN-γ intracelular nas células T CD4+ e CD8+, em comparação com os grupos controlos. Após estimulação das CMSP com M. tuberculosis, os doentes demonstraram um aumento médio de IL-4 intracelular no fenótipo T CD4+, mais evidente na subpopulação T CD8+. O aumento da secreção de IL-4 nos doentes com tuberculose verificou-se sobretudo nos indivíduos em estado avançado da doença. Os resultados obtidos por Citometria de Fluxo contradizem de alguma forma os obtidos por ELISA. A secreção de IL-4 intracelular representa uma medida mais sensível da produção de citocinas tipo 2 do que a quantificação de IL-5 por técnicas de ELISA. Estes novos resultados sugerem que pode ocorrer uma mudança de T 1 para T 2 em doentes com tuberculose em estado avançado.REV PORT PNEUMOL 2001; VII (2): ABSTRACT: In vitro Type 1 and Type 2 cytokine responses were assessed in healthy Portuguese donors who were BGC vaccinated at birth and Mantoux positive (induration 5â¥mm) and pulmonary tuberculosis patients (TB). We evaluated the production of IFN-γ and IL-5, after PBMC from donors were stimulated with live M. tuberculosis H37Rv and the soluble antigen PPD, by standard ELISA techniques. These studies were extended to confirm intracellular presence of IFN-γ and IL-4 in specific T cell subsets by multi-parameter flow cytometry. PBMC from tuberculosis patients demonstrated significantly reduced amounts of IFN-γ when stimulated with PPD and M. tuberculosis, with no increase in IL-5 production towards all the antigens, when compared to the control group. Intracellular staining for IFN-γ in tuberculosis patients showed reduced frequencies of CD4+ and CD8+ T cell intracellular IFN-γ in comparison to healthy subjects. Tuberculosis patients demonstrated a mean increase of intracellular IL-4 after PBMC were stimulated with M. tuberculosis in the CD4+ phenotype, but more notably in the CD8+ subset. The increased secretion of IL-4 in tuberculosis patients was primarily in individuals with an advanced clinical form of the disease. Interestingly the findings using flow cytometry techniques somewhat contradicts the results obtained by ELISA. Intracellular IL-4 secretion is therefore a more sensitive measure of Type 2 cytokine production than quantitation of IL-5 by ELISA. These results suggest that a type 1 switch to a type 2 can occur, in patients with tuberculosis in an advanced stage.REV PORT PNEUMOL 2001; VII (2): Palavras-chave: Imunidade Celular, Tuberculose Pulmonar, Respostas de citocinas Tipo 1 e Tipo 2, Key-words: Cellular Immunity, Pulmonary tuberculosis, Type 1 and Type 2 Cytokine response
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