56 research outputs found

    Information management and social networks in organizational innovation networks

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    Tese de mestrado. Ciência da Informação. Faculdade de Engenharia. Universidade do Porto. 201

    Proanthocyanidins polymeric tannin from Stryphnodendron adstringens are active against Candida albicans biofilms

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    Abstract\ud \ud Background\ud Biofilm formation is important in Candida albicans pathogenesis and constitutes a mechanism of antifungal resistance. Thus, we evaluated the effect of proanthocyanidins polymer-rich fractions from Stryphnodendron adstringens (fraction F2 and subfraction F2.4) against C. albicans biofilms.\ud \ud \ud Methods\ud Firstly, the antifungal activity of F2 and F2.4 against planktonic cells of Candida albicans (ATCC 10231) was determined using broth microdilution method. Anti-biofilm effect of F2 and F2.4 was evaluated during biofilm formation or on mature biofilm of C. albicans and compared with standard antifungals amphotericin B and fluconazole. Metabolic activity of sessile and dispersion cells from biofilms after antifungal treatments were measured using a tetrazolium reduction assay and the biofilm total biomass was quantified by crystal violet-based assay. Morphological alterations after treatments were observed using scanning electron microscopy.\ud \ud \ud Results\ud The anti-biofilm effect of F2 and F2.4 were comparable to standard antifungals (amphotericin B and fluconazole). F2 and F2.4 treatments reduced biofilm metabolic activity (in sessile and in dispersion cells) during biofilm formation, and in mature biofilms, unlike fluconazole, which only prevents the biofilm formation. Treatments with F2, F2.4 or fluconazole reduced biofilm biomass during biofilm formation, but not in mature biofilm. Amphotericin B presented higher inhibitory effect on biofilm formation and on mature biofilm of C. albicans. F2 and F2.4 treatments led to the appearance of dumbbell-shaped blastoconidia and of blastoconidia clusters in biofilms.\ud \ud \ud Conclusion\ud Proanthocyanidins polymer-rich fractions from S. adstringens successfully inhibited C. albicans planktonic growth and biofilm development, and they represent a potential new agent for the treatment of biofilm-associated candidiasis.This work was supported by Fundação de Amparo à Pesquisa\ud do Estado de São Paulo (FAPESP - Processo no. 2013/11232-0), Fundação\ud Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro\ud (FAPERJ), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior\ud (CAPES), and Conselho Nacional de Desenvolvimento e Pesquisa (CNPq).\ud RLFL and TVMV are fellows of the CNPq

    Evaluation of PIK3CA mutations in advanced ER+/HER2-breast cancer in Portugal – U-PIK Project

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    Background: Around 40% of ER+/HER2-breast carcinomas (BC) present mutations in the PIK3CA gene. Assessment of PIK3CA mutational status is required to identify patients eligible for treatment with PI3Kα inhibitors, with alpelisib currently the only approved tyrosine kinase inhibitor in this setting. U-PIK project aimed to conduct a ring trial to validate and implement the PIK3CA mutation testing in several Portuguese centers, decentralizing it and optimizing its quality at national level.Methods: Eight Tester centers selected two samples of patients with advanced ER+/HER2- BC and generated eight replicates of each (n = 16). PIK3CA mutational status was assessed in two rounds. Six centers used the cobas®PIK3CA mutation test, and two used PCR and Sanger sequencing. In parallel, two reference centers (IPATIMUP and the Portuguese Institute of Oncology [IPO]-Porto) performed PIK3CA mutation testing by NGS in the two rounds. The quality of molecular reports describing the results was also assessed. Testing results and molecular reports were received and analyzed by U-PIK coordinators: IPATIMUP, IPO-Porto, and IPO-Lisboa.Results: Overall, five centers achieved a concordance rate with NGS results (allele frequency [AF] ≥5%) of 100%, one of 94%, one of 93%, and one of 87.5%, considering the overall performance in the two testing rounds. NGS reassessment of discrepancies in the results of the methods used by the Tester centers and the reference centers identified one probable false positive and two mutations with low AF (1–3%, at the analytical sensitivity threshold), interpreted as subclonal variants with heterogeneous representation in the tissue sections processed by the respective centers. The analysis of molecular reports revealed the need to implement the use of appropriate sequence variant nomenclature with the identification of reference sequences (HGVS-nomenclature) and to state the tumor cell content in each sample.Conclusion: The concordance rates between the method used by each tester center and NGS validate the use of the PIK3CA mutational status test performed at these centers in clinical practice in patients with advanced ER+/HER2- BC

    Inquérito sorológico sôbre leptospiroses realizado no Vale do Cariri, Estado do Ceará, pela III Bandeira Científica do Centro Acadêmico Oswaldo Cruz da Faculdade de Medicina da Universidade de São Paulo

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    Agglutination-tests for leptospirosis were performed in 376 sera. The following sero-types of Leptospira were used: L. icterohemorrhagiae, L. canicola, L. grippo-typhosa, L. pomona, L. bataviae, L. australis B, L. sejroe, L. pyrogenes and L. suis. Six sera (1.59%) were positive for L. icterohemorrhagiae. From the whole group two people were born in this region, what makes possible the conclusion that the disease exists in the region.Com o propósito de estudar o problema das leptospiroses no Vale do Cariri, Ceará, foram examinados 376 soros colhidos entre moradores da região. Foram feitas provas de sôro-aglutinação usando-se os seguintes sôro-tipos de Leptospira: L. icterohemorrhagiae, L. canícola, L. grippo-typhosa, L. pomona, L. bataviae, L. australis B, L. sejroe, L. pyrogenes e L. suis. Seis soros reagiram positivamente frente à L. icterohemorrhagiae, o que dá percentual de 1,59%. Dois dos indivíduos haviam nascido e vivido no Vale, donde foi possível concluir que a leptospirose existe, autóctone, na região

    SARS-CoV-2 introductions and early dynamics of the epidemic in Portugal

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    Genomic surveillance of SARS-CoV-2 in Portugal was rapidly implemented by the National Institute of Health in the early stages of the COVID-19 epidemic, in collaboration with more than 50 laboratories distributed nationwide. Methods By applying recent phylodynamic models that allow integration of individual-based travel history, we reconstructed and characterized the spatio-temporal dynamics of SARSCoV-2 introductions and early dissemination in Portugal. Results We detected at least 277 independent SARS-CoV-2 introductions, mostly from European countries (namely the United Kingdom, Spain, France, Italy, and Switzerland), which were consistent with the countries with the highest connectivity with Portugal. Although most introductions were estimated to have occurred during early March 2020, it is likely that SARS-CoV-2 was silently circulating in Portugal throughout February, before the first cases were confirmed. Conclusions Here we conclude that the earlier implementation of measures could have minimized the number of introductions and subsequent virus expansion in Portugal. This study lays the foundation for genomic epidemiology of SARS-CoV-2 in Portugal, and highlights the need for systematic and geographically-representative genomic surveillance.We gratefully acknowledge to Sara Hill and Nuno Faria (University of Oxford) and Joshua Quick and Nick Loman (University of Birmingham) for kindly providing us with the initial sets of Artic Network primers for NGS; Rafael Mamede (MRamirez team, IMM, Lisbon) for developing and sharing a bioinformatics script for sequence curation (https://github.com/rfm-targa/BioinfUtils); Philippe Lemey (KU Leuven) for providing guidance on the implementation of the phylodynamic models; Joshua L. Cherry (National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health) for providing guidance with the subsampling strategies; and all authors, originating and submitting laboratories who have contributed genome data on GISAID (https://www.gisaid.org/) on which part of this research is based. The opinions expressed in this article are those of the authors and do not reflect the view of the National Institutes of Health, the Department of Health and Human Services, or the United States government. This study is co-funded by Fundação para a Ciência e Tecnologia and Agência de Investigação Clínica e Inovação Biomédica (234_596874175) on behalf of the Research 4 COVID-19 call. Some infrastructural resources used in this study come from the GenomePT project (POCI-01-0145-FEDER-022184), supported by COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation (POCI), Lisboa Portugal Regional Operational Programme (Lisboa2020), Algarve Portugal Regional Operational Programme (CRESC Algarve2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), and by Fundação para a Ciência e a Tecnologia (FCT).info: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 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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