49 research outputs found
Novel genipin cross-linked chitosan-silk fibroin sponges for cartilage engineering strategies
The positive interaction of materials with tissues is an important step in regenerative medicine strategies. Hydrogels
that are obtained from polysaccharides and proteins are expected to mimic the natural cartilage environment and
thus provide an optimum milleu for tissue growth and regeneration. In this work, novel hydrogels composed of
blends of chitosan and Bombyx mori silk fibroin were cross-linked with genipin (G) and were freeze dried to
obtain chitosan/silk (CSG) sponges. CSG sponges possess stable and ordered structures because of protein
conformational changes from R-helix/random-coil to -sheet structure, distinct surface morphologies, and pH/
swelling dependence at pH 3, 7.4, and 9. We investigated the cytotoxicity of CSG sponge extracts by using L929
fibroblast-like cells. Furthermore, we cultured ATDC5 cells onto the sponges to evaluate the CSG sponges’ potential
in cartilage repair strategies. These novel sponges promoted adhesion, proliferation, and matrix production of
chondrocyte-like cells. Sponges’ intrinsic properties and biological results suggest that CSG sponges may be
potential candidates for cartilage tissue engineering (TE) strategies.S.S.S. and M.T.R. thank the Portuguese Foundation for Science and Technology (FCT) for Ph.D. scholarships (SFRH/BD/8658/2002 and SFRH/BD/30745/2006, respectively). A.F.M.P. thanks the FCT and FEDER for a grant (POCI/FIS/61621/2004). This work was partially supported by the European-Union-funded STREP project HIPPOCRATES (NMP3-CT-2003-505758) and was carried out under the scope of the European NoE EXPERTISSUES (NMP3-CT-2004-500283). We also acknowledge Adriano Pedro for his contribution to the micro-CT analysis
Prevalência, fatores de risco e genótipos da hepatite C entre usuários de drogas
OBJECTIVE: To estimate prevalence of hepatitis C virus (HCV) infection and identify risk factors associated and circulating HCV genotypes and subtypes. METHODS: Study conducted including 691 drug users attending 26 charitable, private and public drug treatment centers in Goiânia and Campo Grande, central-western Brazil, between 2005 and 2006. Sociodemographic characteristics and risk factors for HCV infection were collected during interviews. Blood samples were tested for HCV antibodies (anti-HCV). Positive samples were submitted to HCV RNA detection by PCR with primers complementary to 5' NC and NS5B regions of viral genome and genotyped by line probe assay (LiPA) and direct nucleotide sequencing followed by phylogenetic analysis. The prevalence and odds ratio were calculated with 95% confidence intervals. Risk factors were first estimated in the univariate analysis (pOBJETIVO: Estimar la prevalencia y factores asociados a la infección por el virus de la hepatitis C en usuarios de drogas e identificar los genotipos y subtipos virales circulantes. MÉTODOS: Estudio realizado con 691 usuarios de drogas de 26 centros de tratamiento de uso de drogas filantrópicos, particulares y públicos de Goiania y Campo Grande (Centro-Oeste), entre 2005 y 2006. Datos sociodemográficos y factores de riesgo para infección por el HCV fueron obtenidos por medio de entrevistas. Muestras sanguíneas fueron evaluadas para la detección de anticuerpos para el HCV. Las muestras positivas fueron sometidas a la detección de RNA-HCV por la reacción en cadena de polimerasa con iniciadores complementarios a las regiones 5' NC y NS5B del genoma viral y genotipadas por el line probe assay (LiPA) y por secuenciación directa, seguido del análisis filogenético. Prevalencia y odds ratio fueron calculados con intervalo de 95% de confianza. Los factores de riesgo con pOBJETIVO: Estimar a prevalência e fatores associados à infecção pelo vírus da hepatite C em usuários de drogas e identificar os genótipos e subtipos virais circulantes. MÉTODOS: Estudo realizado com 691 usuários de drogas de 26 centros de tratamento de uso de drogas filantrópicos, particulares e públicos de Goiânia (GO) e Campo Grande (MS), entre 2005 e 2006. Dados sociodemográficos e fatores de risco para infecção pelo HCV foram obtidos por meio de entrevistas. Amostras sangüíneas foram testadas para a detecção de anticorpos para o HCV. As amostras positivas foram submetidas à detecção do RNA-HCV pela reação em cadeia da polimerase com iniciadores complementares às regiões 5' NC e NS5B do genoma viral e genotipadas pelo line probe assay (LiPA) e por seqüenciamento direto, seguido de análise filogenética. Prevalência e odds ratio foram calculados com intervalo de 95% de confiança. Os fatores de risco com
Entre o oficial e o costumeiro: o exercício dos poderes e a espacialização da ruralidade no centro da América do Sul (primeira metade do século XVIII)
Analisamos aqui a relação entre o sistema administrativo português e a formação de ambientes rurais no centro da América do Sul, em territórios que, na primeira metade do século XVIII, integravam o extremo oeste do Estado do Brasil, no âmbito administrativo da capitania de São Paulo. A partir de um enfoque local, examinando correspondências entre autoridades metropolitanas e cartas de sesmarias, este artigo dialoga com a produção histórica sobre a administração portuguesa na América, buscando reconstruir aspectos generalizantes que possam revelar características estruturais da conquista da terra e da formação de ambientes rurais nos territórios portugueses na América.In this article we analyze the relationship between the Portuguese administrative system and formation of rural environments in the center of South America, in territories that in the first half of the eighteenth century comprised the extreme western part of the State of Brazil, under the administrative captaincy of Sao Paulo. From a local focus, analizing letters of metropolitan authorities and documentation of possession of land, this article dialogue with the historical production of the Portuguese administration in America, seeking rebuild generalizing aspects that may prove structural characteristics of the conquest of land and training of rural environments in Portuguese territories in America
WorldFAIR (D10.3) Agricultural biodiversity FAIR data assessment rubrics
The WorldFAIR Case Study on Agricultural Biodiversity (WP10) addresses the challenges of advancing interoperability and mobilising plant-pollinator interactions data for reuse. Previous efforts, reported in WorldFAIR Deliverable 10.1, ‘Agriculture-related pollinator data standards use cases report’ (Trekels et al., 2023), provided an overview of projects, good practices, tools, and examples for creating, managing and sharing data related to plant-pollinator interactions. It also outlined a work plan for conducting pilot studies. Deliverable 10.2 (Drucker et al., 2024) presented Agricultural Biodiversity Standards, Best Practices and Guidelines Recommendations. This deliverable presented results from six pilot studies that adopted standards and recommendations from the earlier report. The current report complements the efforts with Agricultural Biodiversity FAIR data assessment rubrics.We introduce a set of FAIR assessment tools tailored to the plant-pollinator interactions domain. These tools are designed to help researchers and institutions evaluate adherence to the FAIR principles. In the discovery phase, we found that a significant amount of data on plant-pollinator interactions is available as supplementary files of research articles, in a diversity of formats such as PDFs, Excel spreadsheets, and text files. The diversity of approaches and the lack of appropriate data vocabularies lead to confusion, information loss, and the need for complex data interpretation and transformation. Our proposed framework primarily targets researchers in this domain who wish to assess the FAIRness of the data they produce and take action to improve it. However, we believe it can also benefit data reviewers, data stewards, data repository managers and librarians dealing with plant-pollinator data. Our approach focuses on being as familiar as possible with the researcher's practices, language, and jargon. Ultimately, we aim to promote data publishing and reuse in the plant-pollinator interactions domain.We present a ‘Rubric for the assessment of Plant-Pollinator Interactions Data’ with examples from the data from the pilots developed in Deliverable 10.2 and in relation to the FAIR Implementation Profile (FIP) created by Work Package 10. We conduct ‘dataset assessments’ of available data from research projects surveyed in the discovery phase. Additionally, we describe in detail the ‘Automated FAIR-enabled Data Reviews’ generated by the Global Biotic Interactions (GLoBI) infrastructure, with examples from the pilots. We believe the tools described in this report will encourage data publishing and reuse in the plant-pollinator interactions domain. Moving from diverse approaches and siloed initiatives to widely available FAIR plant-pollination interactions data for scientists and decision-makers will enable the development of integrative studies that enhance our understanding of species biology, behaviour, ecology, phenology, and evolution
Life history of three catfish species (Siluriformes: Ariidae) from southeastern Brazil
Alkaline gel electrophoresis assay to detect DNA strand breaks and repair mechanisms in Escherichia coli
Cartografia e diplomacia: usos geopolíticos da informação toponímica (1750-1850)
O artigo explora dimensões geopolíticas da toponímia, registradas em documentos cartográficos, desde as reformas empreendidas pelo consulado pombalino em meados do século XVIII, até às primeiras décadas do século XIX, em meio ao processo de afirmação do Estado imperial pós-colonial.This paper explores the geopolitical dimensions of toponymy as registered in cartographic documents dating from the reforms pushed through by the consulate of Marquis of Pombal in the mid 18th century to the early decades of the 19th century, as the post-colonial imperial State established itself