175 research outputs found

    Green chemistry and biorefineries: common future?

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    Green Chemistry and Biorefinery concepts are two approaches helping to develop new and more sustainable processes.The implementation of both methodologies impels to fossil-independent future with bioeconomy based on natural feedstock like biowaste and industrial by-products. The development of technologies for valorisation of these resources is a key role of society in the creation of sustainable and more environmentally friendly future. Shortly after the Rio Declaration on Environment and Development, Anastas and Warner presented 12 Principles of Green Chemistry but more a decade before Trevor Kletz in his Jubilee lecture entitled “What you don’t have, can’t leak” draw the frames in which scientific and industrial work should be performed. This basis of green chemistry created a fundament for further development and implementation of Anastas and Warner principles of green chemistry. One of these frames is integration of green chemistry principles in the biorefinery concept. The biorefinery is an industrial facility (or network of facilities) that cover an extensive range of combined technologies aiming to full sustainable transformation of biomass into their building blocks with the concomitant production of biofuels, energy, chemicals and materials, preferably of value added products. One of the principles of green chemistry is the use of more sustainable solvents. Some examples of them are ionic liquids (ILs) and supercritical fluids (scF). This work will demonstrate the successful examples of lignocellulosic biomass valorisation using green solvents answering the question regarding the feasibility of future biorefineries made in a greener manner

    Production of fermented cheese whey-based beverage using kefir grains as starter culture : evaluation of morphological and microbial variations

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    Whey valorization concerns have led to recent interest on the production of whey beverage simulating kefir. In this study, the structure and microbiota of Brazilian kefir grains and beverages obtained from milk and whole/deproteinised whey was characterized using microscopy and molecular techniques. The aim was to evaluate its stability and possible shift of probiotic bacteria to the beverages. Fluorescence staining in combination with Confocal Laser Scanning Microscopy showed distribution of yeasts in macro-clusters among the grain’s matrix essentially composed of polysaccharides (kefiran) and bacteria. Denaturing gradient gel electrophoresis displayed communities included yeast affiliated to Kluyveromyces marxianus, Saccharomyces cerevisiae, Kazachatania unispora, bacteria affiliated to Lactobacillus kefiranofaciens subsp. Kefirgranum, Lactobacillus kefiranofaciens subsp. Kefiranofaciens and an uncultured bacterium also related to the genus Lactobacillus. A steady structure and dominant microbiota, including probiotic bacteria, was detected in the analyzed kefir beverages and grains. This robustness is determinant for future implementation of whey-based kefir beverages.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), CAPES-GRICES

    Microglia dysfunction caused by the loss of Rhoa disrupts neuronal physiology and leads to neurodegeneration

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    © 2020 The Author(s). Creative Commons Attribution (CC BY 4.0)Nervous tissue homeostasis requires the regulation of microglia activity. Using conditional gene targeting in mice, we demonstrate that genetic ablation of the small GTPase Rhoa in adult microglia is sufficient to trigger spontaneous microglia activation, producing a neurological phenotype (including synapse and neuron loss, impairment of long-term potentiation [LTP], formation of β-amyloid plaques, and memory deficits). Mechanistically, loss of Rhoa in microglia triggers Src activation and Src-mediated tumor necrosis factor (TNF) production, leading to excitotoxic glutamate secretion. Inhibiting Src in microglia Rhoa-deficient mice attenuates microglia dysregulation and the ensuing neurological phenotype. We also find that the Rhoa/Src signaling pathway is disrupted in microglia of the APP/PS1 mouse model of Alzheimer disease and that low doses of Aβ oligomers trigger microglia neurotoxic polarization through the disruption of Rhoa-to-Src signaling. Overall, our results indicate that disturbing Rho GTPase signaling in microglia can directly cause neurodegeneration.The authors acknowledge the support of the following i3S Scientific Platforms: Animal Facility, Translational Cytometry Unit (TraCy), BioSciences Screening (BS) and Advanced Light Microscopy (ALM), and members of the national infrastructure PPBI-Portuguese Platform of BioImaging (supported by POCI-01–0145-FEDER-022122). FCT Portugal ( PTDC/MED-NEU/31318/2017-031318 ) supported work in the J.B.R. lab. FCT Portugal , PEst ( UID/NEU/04539/2013 ), COMPETE-FEDER ( POCI-01-0145-FEDER-007440 ), Centro 2020 Regional Operational Programme ( CENTRO-01-0145-FEDER-000008 : BrainHealth 2020), and Strategic Project UIDB/04539/2020 and UIDP/04539/2020 (CIBB) supported work in the A.F.A. lab. C.C.P. and R.S. hold employment contracts financed by national funds through FCT (Fundação para a Ciência e a Tecnologia, I.P.) in the context of the program contract described in paragraphs 4, 5, and 6 of article 23 of law no. 57/2016, of August 29th, as amended by law no. 57/2017 of July 19th.info:eu-repo/semantics/publishedVersio

    Diversity of metalloproteinases in Bothrops neuwiedi snake venom transcripts: evidences for recombination between different classes of SVMPs

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    <p>Abstract</p> <p>Background</p> <p>Snake venom metalloproteinases (SVMPs) are widely distributed in snake venoms and are versatile toxins, targeting many important elements involved in hemostasis, such as basement membrane proteins, clotting proteins, platelets, endothelial and inflammatory cells. The functional diversity of SVMPs is in part due to the structural organization of different combinations of catalytic, disintegrin, disintegrin-like and cysteine-rich domains, which categorizes SVMPs in 3 classes of precursor molecules (PI, PII and PIII) further divided in 11 subclasses, 6 of them belonging to PII group. This heterogeneity is currently correlated to genetic accelerated evolution and post-translational modifications.</p> <p>Results</p> <p>Thirty-one SVMP cDNAs were full length cloned from a single specimen of <it>Bothrops neuwiedi </it>snake, sequenced and grouped in eleven distinct sequences and further analyzed by cladistic analysis. Class P-I and class P-III sequences presented the expected tree topology for fibrinolytic and hemorrhagic SVMPs, respectively. In opposition, three distinct segregations were observed for class P-II sequences. P-IIb showed the typical segregation of class P-II SVMPs. However, P-IIa grouped with class P-I cDNAs presenting a 100% identity in the 365 bp at their 5' ends, suggesting post-transcription events for interclass recombination. In addition, catalytic domain of P-IIx sequences segregated with non-hemorrhagic class P-III SVMPs while their disintegrin domain grouped with other class P-II disintegrin domains suggesting independent evolution of catalytic and disintegrin domains. Complementary regions within cDNA sequences were noted and may participate in recombination either at DNA or RNA levels. Proteins predicted by these cDNAs show the main features of the correspondent classes of SVMP, but P-IIb and P-IIx included two additional cysteines cysteines at the C-termini of the disintegrin domains in positions not yet described.</p> <p>Conclusions</p> <p>In <it>B. neuwiedi </it>venom gland, class P-II SVMPs were represented by three different types of transcripts that may have arisen by interclass recombination with P-I and P-III sequences after the divergence of the different classes of SVMPs. Our observations indicate that exon shuffling or post-transcriptional mechanisms may be driving these recombinations generating new functional possibilities for this complex group of snake toxins.</p

    Academics' pesrpectives on Physical Education within the scope of inclusive education

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    Este artículo analiza las perspectivas de los académicos de la Educación Física en el contexto de la enseñanza y de la actuación con los estudiantes con discapacidad en la Educación Física y el Deporte en la escuela. El estudio tiene como objetivo analizar las opiniones de los académicos respecto al contexto de actuación. Esta investigación es de naturaleza descriptiva y transversal abordándose de manera cuantitativa. Se llevó a cabo por medio de una encuesta en la que 82 estudiantes de Educación Física respondieron a un cuestionario. Se realizó distribución de frecuencias, análisis factorial y análisis temático. Los participantes fueron de la opinión de que los objetivos de la Educación Física y el Deporte en la escuela, promover conductas sanas, la práctica del deporte y las relaciones socio-afectivas, son beneficiosas para el desarrollo del trabajo con personas con diferentes discapacidades. Creemos que este trabajo puede ser de ayuda en los planes de estudio de Educación Física y ayudar a gestionar y dirigir mejor la formación de profesores para los alumnos con discapacidades.This article discusses the perspectives of academics on Physical Education within the context of teaching and against the background of working with students with disabilities in Physical Education and Sports in school. The study is descriptive, cross-sectional in nature and seeks to analyze the academics’ opinions regarding Physical Education and Sports in school for students with disabilities. The research, which adopted a quantitative approach, was carried out by way of a survey in which 82 undergraduate students of Physical Education responded to a questionnaire. Distribution of frequencies, factor analysis and thematic analysis were conducted. Participants were of the opinion that the objectives of Physical Education and Sports in school promote healthy behaviour, the playing of sport and socio-affective relationships, as well as they are beneficial to an environment of working with different persons with disabilities. We believe this work may help in the curricula of physical education to better manage and direct the training of academics for students with disabilities.Este artigo discute a perspectiva dos acadêmicos de Educação Física sobre o contexto de ensino e o interesse em atuar com alunos com deficiência em Educação Física e Esportes na escola. O estudo tem por objetivo analisar as opiniões dos acadêmicos sobre o contexto atuação Educação Física e Esportes na escola para alunos com deficiência. O estudo é de natureza descritiva e transversal e que utilizou abordagem quantitativa via pesquisa por levantamento em que 82 alunos de graduação em Educação Física responderam a um questionário. Foi realizada distribuição de frequências, análise fatorial e análise temática. Na opinião dos acadêmicos, os objetivos da Educação Física e Esportes na escola são estimular a adesão de hábitos saudáveis, prática esportiva e relações sócio-afetivas, bem como apresentam interesse em atuar com diferentes públicos com algum tipo de deficiência. Acreditamos esse trabalho pode ajudar nos currículos dos cursos de Educação Física a melhor direcionar a formação dos acadêmicos para o público dos alunos com deficiência.peerReviewe

    Gene Expression Profiling during Early Acute Febrile Stage of Dengue Infection Can Predict the Disease Outcome

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    Background: We report the detailed development of biomarkers to predict the clinical outcome under dengue infection. Transcriptional signatures from purified peripheral blood mononuclear cells were derived from whole-genome gene-expression microarray data, validated by quantitative PCR and tested in independent samples. Methodology/Principal Findings: The study was performed on patients of a well-characterized dengue cohort from Recife, Brazil. The samples analyzed were collected prospectively from acute febrile dengue patients who evolved with different degrees of disease severity: classic dengue fever or dengue hemorrhagic fever (DHF) samples were compared with similar samples from other non-dengue febrile illnesses. The DHF samples were collected 2-3 days before the presentation of the plasma leakage symptoms. Differentially-expressed genes were selected by univariate statistical tests as well as multivariate classification techniques. The results showed that at early stages of dengue infection, the genes involved in effector mechanisms of innate immune response presented a weaker activation on patients who later developed hemorrhagic fever, whereas the genes involved in apoptosis were expressed in higher levels. Conclusions/Significance: Some of the gene expression signatures displayed estimated accuracy rates of more than 95%, indicating that expression profiling with these signatures may provide a useful means of DHF prognosis at early stages of infection. © 2009 Nascimento et al
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