1,899 research outputs found

    Biological potential, gastrointestinal digestion, absorption, and bioavailability of algae-derived compounds with neuroprotective activity: a comprehensive review

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    Currently, there is no known cure for neurodegenerative disease. However, the available therapies aim to manage some of the symptoms of the disease. Human neurodegenerative diseases are a heterogeneous group of illnesses characterized by progressive loss of neuronal cells and nervous system dysfunction related to several mechanisms such as protein aggregation, neuroinflammation, oxidative stress, and neurotransmission dysfunction. Neuroprotective compounds are essential in the prevention and management of neurodegenerative diseases. This review will focus on the neurodegeneration mechanisms and the compounds (proteins, polyunsaturated fatty acids (PUFAs), polysaccharides, carotenoids, phycobiliproteins, phenolic compounds, among others) present in seaweeds that have shown in vivo and in vitro neuroprotective activity. Additionally, it will cover the recent findings on the neuroprotective effects of bioactive compounds from macroalgae, with a focus on their biological potential and possible mechanism of action, including microbiota modulation. Furthermore, gastrointestinal digestion, absorption, and bioavailability will be discussed. Moreover, the clinical trials using seaweed-based drugs or extracts to treat neurodegenerative disorders will be presented, showing the real potential and limitations that a specific metabolite or extract may have as a new therapeutic agent considering the recent approval of a seaweed-based drug to treat Alzheimer’s disease.info:eu-repo/semantics/publishedVersio

    Marine health-promoting compounds: recent trends for their characterization and human applications

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    Seaweeds represent a rich source of biologically active compounds with several applications, especially in the food, cosmetics, and medical fields. The beneficial effects of marine compounds on health have been increasingly explored, making them an excellent choice for the design of functional foods. When studying marine compounds, several aspects must be considered: extraction, identification and quantification methods, purification steps, and processes to increase their stability. Advanced green techniques have been used to extract these valuable compounds, and chromatographic methods have been developed to identify and quantify them. However, apart from the beneficial effects of seaweeds for human health, these natural sources of bioactive compounds can also accumulate undesirable toxic elements with potential health risks. Applying purification techniques of extracts from seaweeds may mitigate the amount of excessive toxic components, ensuring healthy and safer products for commercialization. Furthermore, limitations such as stability and bioavailability problems, chemical degradation reactions during storage, and sensitivity to oxidation and photo-oxidation, need to be overcome using, for example, nanoencapsulation techniques. Here we summarize recent advances in all steps of marine products identification and purification and highlight selected human applications, including food and feed applications, cosmetic, human health, and fertilizers, among others.info:eu-repo/semantics/publishedVersio

    A Critical Comparison of the Advanced Extraction Techniques Applied to Obtain Health-Promoting Compounds from Seaweeds

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    Marine macroalgae are rich in bioactive compounds that can be applied in several fields, mainly food, cosmetics, and medicine. The health-promoting effects of bioactive compounds, such as polyphenols, polysaccharides, carotenoids, proteins, and fatty acids, have been increasingly explored, especially regarding their antioxidant activity and improvement in human health. To extract these valuable compounds, advanced technologies that include Supercritical-Fluid Extraction (SFE), Pressurised-Liquid Extraction (PLE), Ultrasound-Assisted Extraction (UAE), Microwave-Assisted Extraction (MAE), Enzyme-Assisted Extraction (EAE), Ultrasound-Microwave-Assisted Extraction (UMAE) and Liquefied Gas Extraction (LGE) have been assessed due to their notable advantages over the conventional methods (Solid–Liquid and Soxhlet extraction). These advanced techniques are considerably influenced by different extraction parameters such as temperature, pressure, type of solvent, extraction time, solvent:solid material ratio, power (MAE, UAE, and UMAE), enzymes used (EAE), and factors related to the macroalgae matrix itself. Optimizing these process parameters for each method is critical to obtain better efficiency results for the targeted bioactive compounds. Macroalgae are natural sources with undeniable beneficial effects on human health. In this context, optimising the extraction techniques discussed in this review should prioritise exploiting these valuable resources’ wide range of bioactive propertiesThis work was financed by FEDER—Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020—Operacional Programme for Competitiveness and Internationalisation (POCI), and by Portuguese funds through FCT—Fundação para a Ciência e a Tecnologia in the framework of the project POCI-01-0145-FEDER-030240—PTDC/OCE-ETA/30240/2017—SilverBrain-From sea to brain: Green neuroprotective extracts for nanoencapsulation and functional food production. This work was supported by projects REQUIMTE/LAQV—UIDB/50006/2020, UIDP/50006/2020, and LA/P/0008/2020 financed by FCT/Ministério da Ciência, Tecnologia e Ensino Superior (MCTES), through national funds, and the project SYSTEMIC, “An integrated approach to the challenge of sustainable food systems: adaptive and mitigatory strategies to address climate change and malnutrition”. The Knowledge hub on Nutrition and Food Security received funding from national research funding parties in Belgium (FWO), France (INRA), Ger-many (BLE), Italy (MIPAAF), Latvia (IZM), Norway (RCN), Portugal (FCT), and Spain (AEI) in a joint action of JPI HDHL, JPI-OCEANS, and FACCE-JPI launched in 2019 under the ERA-NET ERA-HDHL (n° 696295). Clara Grosso (CEECIND/03436/2020) thanks FCT for fundinginfo:eu-repo/semantics/publishedVersio

    OVÍDIO E A LITERATURA DO EXÍLIO

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    Este artigo é resultado das disciplinas Estudos Monográficos I, realizada no segundo semestre de 2006, e a que cursamos atualmente, Estudos Monográficos II. Ele consiste em uma pequena apresentação de Ovídio e de sua literatura do exílio. Fazemos, primeiramente, uma pequena introdução sobre a vida do poeta e suas principais obras. Em seguida, discutimos a(s) possível(is) causa(s) que levou(aram) Ovídio ao desterro e, finalmente, comentamos as principais características dos Tristes e das Pônticas

    Pônticas de Ovídio: um estudo introdutório

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    Este artigo consiste em uma pequena apresentação das Pônticas de Ovídio, escritas provavelmente entre os anos 12 e 16 d.C. Fazemos, primeiramente, uma pequena introdução sobre a vida do poeta e suas principais obras. Em seguida, discutimos as possíveis causas que levaram Ovídio ao desterro e, finalmente, comentamos algumas passagens dessa obra

    A questão do gênero nas Pônticas de Ovídio

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    Este trabalho visa discutir a diferenciação do gênero nas Pônticas e nos Tristes de Ovídio, considerando que parece haver uma relação contrária e inversamente proporcional entre essas produções do exílio: os Tristes pertencem ao gênero elegíaco, com fortes características do gênero epistolar na maioria de suas elegias; as Pônticas, ao gênero epistolar, com grandes marcas elegíacas

    Book I of Ovid's Epistulae ex Ponto : comment and translation

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    Orientador: Patricia PrataDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Estudos da LinguagemResumo: Esta dissertação consiste no comentário e na tradução do livro I das Pônticas de Ovídio. O comentário proposto baseia-se em uma comparação entre esta obra e os Tristes, ambas produções da época do exílio do poeta Ovídio. Enfatizaremos a questão do gênero, que nos parece ser um dos pontos principais de aproximação entre elas, bem como os assuntos que abordam, já que o próprio Ovídio chama a atenção para as semelhanças temáticas entre essas obras. A tradução, acompanhada de notas explicativas (relativas a referências mitológicas, geográficas e históricas, bem como a escolhas tradutórias ou dificuldades do texto latino), foi realizada a partir da edição do poema na série Les Belles Lettres, e tem como propósito divulgar parte dessa obra, já que não há, ao que saibamos, tradução completa em verso deste livro para a língua portuguesa aqui no Brasil, apenas uma tradução em prosa, que data de 2009Abstract: This dissertation consists of the comment and translation of Book I of Ovid¿s Epistulae ex Ponto. The proposed comment is based on a comparison between this work and Tristia, both productions of the poet Ovid's exile period. We emphasize the genre issue, which seems to be one of the main points of approch between them, as well as another issues to be discussed, since Ovid himself calls attention to the thematic similarities between these works. Translation, accompanied by explanatory notes (related to mythological, geographical and historical references, as well as translational choices or difficulties with the original Latin text), was based in the poem published by Les Belles Lettres series, and aims to disseminate part of work, since there isn¿t, as for as we know, complete verse translation of this book into Portuguese in Brazil, only a translation in prose, dated 2009MestradoLinguisticaMestra em LinguísticaCAPE

    An online algorithm for dynamic NFV placement in cloud-based autonomous response networks

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    Autonomous response networks are becoming a reality thanks to recent advances in cloud computing, Network Function Virtualization (NFV) and Software-Defined Networking (SDN) technologies. These enhanced networks fully enable autonomous real-time management of virtualized infrastructures. In this context, one of the major challenges is how virtualized network resources can be effectively placed. Although this issue has been addressed before in cloud-based environments, it is not yet completely resolved for the online placement of virtual machines. For such a purpose, this paper proposes an online heuristic algorithm called Topology-Aware Placement of Virtual Network Functions (TAP-VNF) as a low-complexity solution for such dynamic infrastructures. As a complement, we provide a general formulation of the network function placement using the service function chaining concept. Furthermore, two metrics called consolidation and aggregation validate the efficiency of the proposal in the experimental simulations. We have compared our approach with optimal solutions, in terms of consolidation and aggregation ratios, showing a more suitable performance for dynamic cloud-based environments. The obtained results show that TAP-VNF also outperforms existing approaches based on traditional bin packing schemes.Postprint (published version

    Comprehensive review on the interaction between natural compounds and brain receptors: Benefits and toxicity

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    Given their therapeutic activity, natural products have been used in traditional medicines throughout the centuries. The growing interest of the scientific community in phytopharmaceuticals, and more recently in marine products, has resulted in a significant number of research efforts towards understanding their effect in the treatment of neurodegenerative diseases, such as Alzheimer's (AD), Parkinson (PD) and Huntington (HD). Several studies have shown that many of the primary and secondary metabolites of plants, marine organisms and others, have high affinities for various brain receptors and may play a crucial role in the treatment of diseases affecting the central nervous system (CNS) in mammalians. Actually, such compounds may act on the brain receptors either by agonism, antagonism, allosteric modulation or other type of activity aimed at enhancing a certain effect. The current manuscript comprehensively reviews the state of the art on the interactions between natural compounds and brain receptors. This information is of foremost importance when it is intended to investigate and develop cutting-edge drugs, more effective and with alternative mechanisms of action to the conventional drugs presently used for the treatment of neurodegenerative diseases. Thus, we reviewed the effect of 173 natural products on neurotransmitter receptors, diabetes related receptors, neurotrophic factor related receptors, immune system related receptors, oxidative stress related receptors, transcription factors regulating gene expression related receptors and blood-brain barrier receptors.The author A.R.S. is grateful to the authors C.G. and J.M.R for the scientific assistance and suggestions shared throughout the supervision of her B.Sc. final project. The author A.R.S. also acknowledges the Department of Biology (DB) and the Centro de Biologia Molecular e Ambiental [Centre of Molecular and Environmental Biology] (CBMA) from School of Sciences (EC), University of Minho (UM), Braga, Portugal, by providing all the conditions leading to the B.Sc. in Biochemistry. The corresponding author C.G. is grateful to Fundação para a Ciência e a Tecnologia [Foundation for Science and Technology, FCT I.P.] (FCT I.P.) for the FCT Investigator (IF/01332/2014/CP1255/CT0001). The author J.M.R. acknowledges the CBMA and the Instituto de Ciência e Inovação para a Biosustentabilidade [Institute of Science and Innovation for Biosustainability] (IBS) from University of Minho (UM), Braga, Portugal, where he recently carried out his activities as invited assistant researcher and professor. The author J.M.R. is also grateful to the Laboratório Associado para a Química Verde (LAQV) [Green Chemistry Laboratory] from REQUIMTE – Rede de Química e Tecnologia [REQUIMTE – Chemistry and Technology Network], as well as to the Department of Chemistry and Biochemistry (DCB) from the Faculty of Sciences from University of Porto (FCUP), Porto, Portugal, where he is currently researcher. Regarding to the author J.M.R., this work was supported by the strategic programmes UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) (Research project entitled “EcoAgriFood: Innovative green products and processes to promote Agri-Food BioEconomy”) and PTDC/SAUNUT/30448/2017 (POCI-01-0145-FEDER-030448) (Research project entitled “Poly4CD: Action of Dietary Polyphenols in Preventing Celiac Disease”) funded by Portuguese national funds through Fundação para a Ciência e Tecnologia [Foundation for Science and Technology] (FCT-I.P.)/Ministério da Ciência, Tecnologia e Ensino Superior [Ministry of Science, Technology and Higher Education] (MCTES), and Fundo Europeu de Desenvolvimento Regional [European Regional Development Fund] (FEDER), under the scope of the COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) [COMPETE2020 – Competitiveness and Internationalization Operational Program] and by COST Action 18101 “SOURDOMICS”, supported by COST (European Cooperation in Science and Technology). C. G. and C. D.-M. are grateful for the financial support from FCT/MCTES through national funds (UID/QUI/50006/2019). C. G. and C. D.-M. would also like to thank the EU and FCT for funding through the projects: DESignBIOtecHealth - New Technologies for three Health Challenges of Modern Societies: Diabetes, Drug Abuse and Kidney Diseases (Portugal2020, Norte-01-0145-FEDER-000024) and project PTDC/OCE-ETA/30240/2017- SilverBrain - From sea to brain: Green neuroprotective extracts for nanoencapsulation and functional food production (POCI-01-0145-FEDER-030240); and to the REQUIMTE for the project “Sea_4_Brain_Food”. All the authors acknowledge the CBMA and IB-S by the financial support provided specifically for this open access publication.info:eu-repo/semantics/publishedVersio

    El transporte urbano en la Región Metropolitana de Buenos Aires

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    El objetivo de este trabajo consiste en el análisis de la oferta actual del transporte urbano en la Región metropolitana de Buenos Aires, en el marco de las concesiones otorgadas a empresas privadas, de los servicios públicos de transporte, tratando de evaluar las políticas y modalidades de regulación y gestión aplicadas desde el Estado y centrando la mirada en los efectos y consecuencias de esta modalidad, sobre el conjunto social involucrado y sobre el territorio. Se presentará un panorama general de la situación del sistema de transporte y circulación urbana a modo de síntesis diagnostica, que incluye las características más significativas movilidad, los distintos modos de transportación, los procesos de concesión de la red de accesos a la ciudad madre, del transporte público, tanto automotor como ferroviario de pasajeros y de las nuevas modalidades que incrementaron la oferta. Asimismo en el contexto de la Reforma del Estado, - privatizaciones y concesiones-, se incorporaran algunas reflexiones haciendo hincapié en los impactos que estos procesos provocaron en lo social, espacial-económico y ambiental, y que favorecieron el recrudecimiento de la exclusión y fractura social, y la fragmentación territorial, fenómenos ocurridos de manera general en todas las ciudades latinoamericanas sin distinción de niveles de jerarquía urbana o límites jurisdiccionales pero recortando espacialmente el estudio en la Región metropolitana de Buenos Aires. Toda la reflexión se apoya en el marco del enfoque sistémico, partiendo de considerar que la realidad es compleja y multidimensional y que su naturaleza no es unívoca, que los elementos que la constituyen están interrelacionados entre si, por lo que existen múltiples relaciones ínter- temáticas e ínter-escalares
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