Índice de alteração do carbono no solo, em conversões de uso do solo envolvendo plantações florestais no Brasil.

O uso e a mudança no uso do solo têm efeitos diretos e indiretos sobre a cobertura vegetal e, portanto, podem afetar os estoques de carbono do solo, alterando o equilíbrio entre o sequestro e as taxas de perdas de carbono. Com aproximadamente dez milhões de hectares no Brasil, as florestas plantadas representam um sumidouro de carbono importante no inventário nacional de emissões e remoções de gases de efeito estufa. Para estimativa dos estoques de carbono do setor de reflorestamento, o Brasil adota um índice de alteração de estoques de carbono do solo (IAC) de 0,673, originalmente indicado para culturas agrícolas. Esse fator penaliza os plantios florestais sugerindo que mais de 30% do carbono armazenado no solo é perdido pela conversão de uso. Muitos estudos nacionais questionam essa perda acentuada de carbono pelas florestas plantadas e, portanto, é importante mensurar o impacto das conversões de uso do solo envolvendo florestas plantadas sobre os estoques de carbono do solo, visando propor um novo índice de alteração de carbono para este setor. Para tanto, analisou-se um conjunto de 41 estudos realizados no País, que contabilizaram estoques de carbono no solo em plantios florestais, implantados após a retirada de vegetação nativa de floresta ou campo, pastagem ou agricultura. Esses estudos estão distribuídos em 41 municípios do Brasil e contemplam plantios de eucaliptos, pinus e acácia-negra. A base de dados abrangeu nove estados (RS, SC, PR, SP, ES, MG, BA, PA e MS), cuja área de florestas plantadas soma, atualmente, mais de 8,6 milhões de hectares. A análise realizada indica ganho de 11% no estoque de carbono do solo para plantios de eucalipto em áreas originalmente de um campo nativo e pastagens, e uma perda média de 13% no estoque de carbono do solo para plantios de pinus, independente do uso anterior. Baseado nesse conjunto de dados, a média do IAC do solo para plantios de pinus e eucalipto no Brasil é 0,95, indicando perdas menos intensas do que as consideradas no último inventário nacional publicado em 2016, e sugerindo a necessidade de atualização do IAC para florestas plantadas. A adoção de valores que refletem a realidade nacional quanto aos aspectos de sequestro de carbono é essencial para a confiabilidade dos dados nacionais oficiais de emissões e remoções de gases de efeito estufa, pois estes orientam a elaboração e execução das políticas públicas de controle e mitigação das mudanças climáticas, agregando melhorias contínuas às ferramentas de gestão dessas políticas, como o inventário nacional apresentado pela Comunicação Nacional de Emissões e Remoções de Gases de Efeito Estufa.bitstream/item/217027/1/Livro-Doc-342-1804-final-2.pd

Antiphospholipid Antibodies Bind ATP: A putative Mechanism for the Pathogenesis of Neuronal Dysfunction

Antiphospholipid antibodies (aPL) generated in experimental animals cross-react with ATP. We therefore examined the possibility that aPL IgG from human subjects bind to ATP by affinity column and an enzyme linked immunosorbent assay (ELISA). Sera with high levels of aPL IgG were collected from 12 patients with the antiphospholipid syndrome (APS). IgG fractions from 10 of 12 APS patients contained aPL that could be affinity-bound to an ATP column and completely eluted with NaCl 0.5 M. A significant (>50%) inhibition of aPL IgG binding by ATP 5 mM was found in the majority. Similar inhibition was obtained with ADP but not with AMP or cAMP. All the affinity purified anti-ATP antibodies also bound β2-glycoprotein-I (β2-GPI, also known as apolipoprotein H) suggesting that, similar to most pathogenic aPL, their binding depends on this serum cofactor. We further investigated this possibility and found that the binding of β2-GPI to the ATP column was similar to that of aPL IgG in that most was reversed by NaCl 0.5 M. Furthermore, addition of β2-GPI to aPL IgG significantly increased the amount of aPL binding to an ATP column. We conclude that aPL IgG bind ATP, probably through β2-GPI. This binding could interfere with the normal extracellular function of ATP and similar neurotransmitters

Impact of climate change on eucalyptus plantations in southern Brazil.

Climate change may mean significant changes in crop productivity, including for planted forests, due to changes in climatic parameters. These impacts may be more intense in some regions of the country. Scientific investigation based on field data obtained over the long term and projected scenarios are important tools for planning and decision making that can help decrease vulnerability and risk for the forest sector in the near future. Along these lines, this study (which was conducted with support from Klabin S.A., a forest-based company) indicates changes that may be on the horizon, discusses climatic behavior in some regions of Brazil which are important centers for eucalyptus production, and projects impacts on productivity and carbon emissions/removal capacity in eucalyptus forests within the scenario of climate change. A highlight of this study is the use of the HadGEM2-ES model to predict rainfall, average temperature, evapotranspiration, water deficit, frost events, and minimum temperature at 10-year intervals until 2040. This is a differential, since other studies consider longer intervals. The study indicates climatic risk and the resulting impact on eucalyptus production in southern Brazil. However, detailed investigation in the municipalities of Itapetininga, Telêmaco Borba, and Otacílio Costa points to variations in the vulnerability of these environments. The study also examines the potential of these eucalyptus forests to accumulate carbon, indicating how and to what extent this function may be affected. Predicting potential changes is an intelligent way to prepare for and even ameliorate the impacts of climate change, thus making it possible to maintain the potential for the region and eucalyptus forests to make significant contributions to environmental quality and reaffirm the opportunities that are present for the forest sector within the context of the green economy and decarbonization of the economy

Recombinant humanised anti-HER2/neu antibody (Herceptin®) induces cellular death of glioblastomas

Glioblastoma multiforme (GBM) remains the most devastating primary tumour in neuro-oncology. Targeting of the human epithelial receptor type 2 (HER2)-neu receptor by specific antibodies is a recent well-established therapy for breast tumours. Human epithelial receptor type 2/neu is a transmembrane tyrosine/kinase receptor that appears to be important for the regulation of cancer growth. Human epithelial receptor type 2/neu is not expressed in the adult central nervous system, but its expression increases with the degree of astrocytoma anaplasia. The specificity of HER2/neu for tumoral astrocytomas leads us to study in vitro treatment of GBM with anti-HER2/neu antibody. We used human GBM cell lines expressing HER2/neu (A172 express HER2/neu more than U251MG) or not (U87MG) and monoclonal humanised antibody against HER2/neu (Herceptin®). Human epithelial receptor type 2/neu expression was measured by immunohistochemistry and flow cytometry. Direct antibody effect, complement-dependent cytotoxicity and antibody-dependent cellular cytotoxicity were evaluated by different cytometric assays. We have shown, for the first time, the ability of anti-HER2/neu antibodies to induce apoptosis and cellular-dependent cytotoxicity of HER2/neu-expressing GBM cell lines. The results decreased from A172 to U251 and were negative for U87MG, in accordance with the decreasing density of HER2/neu receptors

Épigénome et syndrome de Gougerot-Sjögren

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Suggestion of a classification for urinary calculi in a pediatric population from brittany

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Carbon storage accounting in brazilian harvested wood products.

ABSTRAC. Brazil is one of the world's leading manufacturers of forest products, and 94% of the raw material comes from cultivated forests, mainly of the Pinus and Eucalyptus genera. Harvested wood products (HWP) can be an important carbon pool, based on the estimated carbon stored in the products in use. Thus, as of 2006, the IPCC began to allow the inclusion of these estimates in national inventories of greenhouse gas emissions. However, Brazil only started to consider these removals and carbon emissions by HWP in the 2020 version of the inventory (base year 2016). The primary data of forest production used in this study were obtained from the database of FAO (FAOSTAT) and of IBGE (Brazilian Institute of Geography and Statistics). Only products manufactured with raw material from planted forests were considered. The methodology for calculating the emission and removal of carbon dioxide followed the IPCC guidelines defined in 2006. Three groups of products were considered: sawnwood; wood-based panels; and paper and cardboard. Of the three approaches commonly used to estimate carbon absorption and emission, the most advantageous calculation was the atmospheric flow method, which is based on carbon fluxes rather than stock changes. This approach benefits major wood products exporting countries, such as Brazil. To calculate the estimates, production in the last year (2016) of 13.4 million m3 of sawnwood, 9.63 million m3 of wood panels and 10.3 million tons of paper and cardboard were considered. The estimates obtained indicate that, in 2016 (considering the period 1990-2016), the annual net contribution of forest products estimated by the atmospheric flow approach was the removal of - 50,772 Gg of CO2eq. This removal corresponds to about 3.5% of Brazil's total emissions and 12.8% of LULUCF (Land Use, Land-Use Change and Forestry) activities emission

Signature et conséquences des anomalies de méthylation de l’ADN au cours du syndrome sec de Gougerot–Sjögren

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