173 research outputs found

    Verification of the selectivity of a liquid chromatography method for determination of stilbenes and flavonols in red wines by mass spectrometry.

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    Quantification of bioactive phenols, like stilbenes and flavonols (SaF), has been conducted to evaluate the nutraceutical potential of red wines. However, there is still a lack of full validated, fast and accessible liquid chromatography methods offering high selectivity and a simple procedure. We present here the use of a high-resolution mass spectrometer to evaluate the selectivity of a feasible and traditional liquid chromatography technique (HPLC? DAD) to analyze markers of aglycone SaF in red wines. The SaF compounds were tested: trans-resveratrol, trans-eviniferin, quercetin, myricetin, and kaempferol, as well as trans-cinnamic acid, one of their precursors. System suitability and validation tests were employed for the selected conditions (octylsilane column, methanol mobile phase, and gradient elution). The validation process ensured the HPLC?DAD method was selective, linear, sensitive, precise, accurate and robust. The method was then applied to red wine samples from the Campanha Gau´cha region, Southern Brazil. The real samples contained different SaF levels, showing that the method is applicable to routine use. Furthermore, this was the first SaF characterization of red wines from the Campanha Gau´cha, contributing to regional and product development. Keywords Bioactive phenols Red wine Liquid chromatography Mass spectrometry Validatio

    Validation of a chromatographic method to routine analysis of transresveratrol and quercetin in red wines.

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    The objective of this work was to validate a fast method with low-solvent use, for the analysis of trans-resveratrol and quercetin in red wines. The wines were prepared, using a classical method, from the grape (Vitis vinifera) cultivars Cabernet Franc, Cabernet Sauvignon, Malbec, Merlot, Petit Verdot, Pinot Noir, Ruby Cabernet, Syrah, Tannat, and Tempranillo. Samples were filtered and analyzed by high-pressure liquid chromatography (HPLC) with a diode array detector (DAD), at 306 and 371 nm, for trans-resveratrol and quercetin, respectively. An octylsilane column was used, and the mobile phase was composed by a gradient of methanol, water, and formic acid. The method was validated according to the following figures of merit: specificity, linearity, limit of detection, limit of quantification, precision, accuracy, and robustness. The proposed HPLC-DAD method may be established for the analysis of trans-resveratrol and quercetin in red wines. Index terms: Vitis vinifera , high-pressure liquid chromatography, polyphenol, quantification. Validação de método cromatográfico para análises de rotina de trans-resveratrol e quercetina em vinhos tintos O objetivo deste trabalho foi validar um método rápido, com baixo consumo de solventes, para a análise de trans-resveratrol e quercetina em vinhos tintos. Os vinhos foram elaborados por método clássico, a partir das cultivares de uva (Vitis vinifera) Cabernet Franc, Cabernet Sauvignon, Malbec, Merlot, Petit Verdot, Pinot Noir, Ruby Cabernet, Syrah, Tannat e Tempranillo. As amostras foram filtradas e analisadas por cromatografia líquida de alta eficiência (CLAE) com detector de arranjo de diodos (DAD), em 306 e 371 nm, quanto ao trans-resveratrol e à quercetina, respectivamente. Utilizou-se uma coluna octilsilano, e a fase móvel foi composta por um gradiente de metanol, água e ácido fórmico. O método foi validado de acordo com as seguintes figuras de mérito: especificidade, linearidade, limite de detecção, limite de quantificação, precisão, exatidão e robustez. O método CLAE-DAD proposto pode ser implantado para análises de transresveratrol e quercetina em vinhos tintos. Termos para indexação: Vitis vinifera, cromatografia líquida de alta eficiência, polifenol, quantificação

    Determinação de fenóis bioativos em vinhos tintos da"Campanha Gaúcha".

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    XV Congresso Latino-Americano de Viticultura e Enologia E XIII Congresso Brasileiro de Viticultura e Enologia. Bento Gonçalves-RS, 3 a 7 de Novembro de 2015

    Nutraceutical evaluation of red wines from 'Campanha Gaúcha' by a feasible HPLC-DAD method for bioactive polyphenols.

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    This work proposes a fast HPLC-DAD method, without exhaustive manipulation of sample, for the analysis of seven BP (trans-resveratrol, quercetin, viniferin, rutin, kaempferol, myricetin and cinnamic acid) in red wines from CG

    Integrating isotopes and documentary evidence : dietary patterns in a late medieval and early modern mining community, Sweden

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    We would like to thank the Archaeological Research Laboratory, Stockholm University, Sweden and the Tandem Laboratory (Ångström Laboratory), Uppsala University, Sweden, for undertaking the analyses of stable nitrogen and carbon isotopes in both human and animal collagen samples. Also, thanks to Elin Ahlin Sundman for providing the δ13C and δ15N values for animal references from Västerås. This research (Bäckström’s PhD employment at Lund University, Sweden) was supported by the Berit Wallenberg Foundation (BWS 2010.0176) and Jakob and Johan Söderberg’s foundation. The ‘Sala project’ (excavations and analyses) has been funded by Riksens Clenodium, Jernkontoret, Birgit and Gad Rausing’s Foundation, SAU’s Research Foundation, the Royal Physiographic Society of Lund, Berit Wallenbergs Foundation, Åke Wibergs Foundation, Lars Hiertas Memory, Helge Ax:son Johnson’s Foundation and The Royal Swedish Academy of Sciences.Peer reviewedPublisher PD

    Geographical origin authentication of southern Brazilian red wines by means of EEM-pH four-way data modelling coupled with one class classification approach.

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    EEM data recorded at different pH values was exploited by MCR-ALS in order to determine qualitative information about Brazilian red wines. In addition, the geographical traceability of wines produced in the Serra Gaúcha (Rio Grande do Sul) was carried out by DD-SIMCA considering 53 samples from the target class and 20 from other producing regions. The fluorescence signal corresponds to 9 EEMs recorded at different pH (3?11), generating four-way data. By MCR-ALS decomposition, eight factors were retrieved and related to typical chemical compounds found in red wine. In addition, the EEM pH data was used to build a one-class classification model, considering that MCR scores and all samples of the target class were properly recognised as belonging to the target class, with maximal sensitivity equal to 1. Samples of the non-target class were also adequately rejected by the model, and the specificity was found to be 0.97

    From Motion to Emotion : Accelerometer Data Predict Subjective Experience of Music

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    Music is often discussed to be emotional because it reflects expressive movements in audible form. Thus, a valid approach to measure musical emotion could be to assess movement stimulated by music. In two experiments we evaluated the discriminative power of mobile-device generated acceleration data produced by free movement during music listening for the prediction of ratings on the Geneva Emotion Music Scales (GEMS-9). The quality of prediction for different dimensions of GEMS varied between experiments for tenderness (R12(first experiment) = 0.50, R22(second experiment) = 0.39), nostalgia (R12 = 0.42, R22 = 0.30), wonder (R12 = 0.25, R22 = 0.34), sadness (R12 = 0.24, R22 = 0.35), peacefulness (R12 = 0.20, R22 = 0.35) and joy (R12 = 0.19, R22 = 0.33) and transcendence (R12 = 0.14, R22 = 0.00). For others like power (R12 = 0.42, R22 = 0.49) and tension (R12 = 0.28, R22 = 0.27) results could be almost reproduced. Furthermore, we extracted two principle components from GEMS ratings, one representing arousal and the other one valence of the experienced feeling. Both qualities, arousal and valence, could be predicted by acceleration data, indicating, that they provide information on the quantity and quality of experience. On the one hand, these findings show how music-evoked movement patterns relate to music-evoked feelings. On the other hand, they contribute to integrate findings from the field of embodied music cognition into music recommender systems

    Minocycline Synergizes with N-Acetylcysteine and Improves Cognition and Memory Following Traumatic Brain Injury in Rats

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    Background: There are no drugs presently available to treat traumatic brain injury (TBI). A variety of single drugs have failed clinical trials suggesting a role for drug combinations. Drug combinations acting synergistically often provide the greatest combination of potency and safety. The drugs examined (minocycline (MINO), N-acetylcysteine (NAC), simvastatin, cyclosporine A, and progesterone) had FDA-approval for uses other than TBI and limited brain injury in experimental TBI models. Methodology/Principal Findings: Drugs were dosed one hour after injury using the controlled cortical impact (CCI) TBI model in adult rats. One week later, drugs were tested for efficacy and drug combinations tested for synergy on a hierarchy of behavioral tests that included active place avoidance testing. As monotherapy, only MINO improved acquisition of the massed version of active place avoidance that required memory lasting less than two hours. MINO-treated animals, however, were impaired during the spaced version of the same avoidance task that required 24-hour memory retention. Coadministration of NAC with MINO synergistically improved spaced learning. Examination of brain histology 2 weeks after injury suggested that MINO plus NAC preserved white, but not grey matter, since lesion volume was unaffected, yet myelin loss was attenuated. When dosed 3 hours before injury, MINO plus NAC as single drugs had no effect on interleukin-1 formation; together they synergistically lowered interleukin-1 levels. This effect on interleukin-1 was not observed when th

    Sub region-specific modulation of synchronous neuronal burst firing after a kainic acid insult in organotypic hippocampal cultures

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    <p>Abstract</p> <p>Background</p> <p>Excitotoxicity occurs in a number of pathogenic states including stroke and epilepsy. The adaptations of neuronal circuits in response to such insults may be expected to play an underlying role in pathogenesis. Synchronous neuronal firing can be induced in isolated hippocampal slices and involves all regions of this structure, thereby providing a measure of circuit activity. The effect of an excitotoxic insult (kainic acid, KA) on Mg<sup>2+</sup>-free-induced synchronized neuronal firing was tested in organotypic hippocampal culture by measuring extracellular field activity in CA1 and CA3.</p> <p>Results</p> <p>Within 24 hrs of the insult regional specific changes in neuronal firing patterns were evident as: (i) a dramatic <it>reduction </it>in the ability of CA3 to generate firing; and (ii) a contrasting <it>increase </it>in the frequency and duration of synchronized neuronal firing events in CA1. Two distinct processes underlie the increased propensity of CA1 to generate synchronized burst firing; a lack of ability of the CA3 region to 'pace' CA1 resulting in an increased frequency of synchronized events; and a change in the 'intrinsic' properties limited to the CA1 region, which is responsible for increased event duration. Neuronal quantification using NeuN immunoflurescent staining and stereological confocal microscopy revealed no significant cell loss in hippocampal sub regions, suggesting that changes in the properties of neurons within this region were responsible for the KA-mediated excitability changes.</p> <p>Conclusion</p> <p>These results provide novel insight into adaptation of hippocampal circuits following excitotoxic injury. KA-mediated disruption of the interplay between CA3 and CA1 clearly increases the propensity to synchronized firing in CA1.</p

    Enhancing Participatory Strategies With Designerly Ways for Sociolegal Impact: Lessons From Research Aimed at Making Hate Crime Visible

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    This paper draws the attention of impact-curious sociolegal researchers to the potential of participatory research strategies; and proposes that the effectiveness of those strategies can be enhanced by the introduction of ‘designerly ways’. It explores and evidences this proposition through the multi-country Facing All the Facts project which aimed to support and accelerate the process of making hate crime conceptually and empirically visible in Europe. The paper concludes that by pursuing the designerly strategy of making experiences, perceptions and expectations around hate crime reporting and recording visible and tangible in artefacts (formal graphics and collaborative prototypes), the project activities generated structured-yet-free spaces in which publics/stakeholders could more effectively participate in practical, critical and imaginative discussion about how things are, and how they might be; and that this has improved the relevance and rigour of the research, and its ability to generate meaningful change (‘impact’)
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