84 research outputs found

    Demixing and orientational ordering in mixtures of rectangular particles

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    Using scaled-particle theory for binary mixtures of two-dimensional hard particles with rotational freedom, we analyse the stability of nematic phases and the demixing phase behaviour of a variety of mixtures, focussing on cases where at least one of the components consists of hard rectangles or hard squares. A pure fluid of hard rectangles may exhibit, aside from the usual uniaxial nematic phase, an additional (tetratic) oriented phase, possessing two directors, which is the analogue of the biaxial or cubatic phases in three- dimensional fluids. There is computer simulation evidence that the tetratic phase might be stable with respect to phases with spatial order for rectangles with low aspect ratios. As hard rectangles are mixed with other particles not possessing stable tetratic order by themselves, the tetratic phase is destabilised, via a first- or second-order phase transition, to uniaxial nematic or isotropic phases; for hard rectangles of low aspect ratio tetratic order persists in a relatively large range of volume fractions. The order of these transitions depends on the particle geometry, dimensions and thermodynamic conditions of the mixture. The second component of the mixture has been chosen to be hard discs or disco-rectangles, the geometry of which is different from that of rectangles, leading to packing frustration and demixing behaviour, or simply rectangles of different aspect ratio. These mixtures may be good candidates for observing thermodynamically stable tetratic phases in monolayers of hard particles. Finally, demixing between fluid (isotropic--tetratic or tetratic--tetratic) phases is seen to occur in mixtures of hard squares of different sizes when the size ratio is sufficiently large.Comment: 27 pages, 9 figure

    Polyphenolic profile of persimmon leaves by high resolution mass spectrometry (LC-ESI-LTQ-Orbitrap-MS)

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    [EN] Persimmon leaves have played an important role in Chinese medicine. Persimmon extracts and formulations have been shown to possess a wide range of pharmacological activities, including antioxidant, hypolipidaemic and antidiabetic, and they have been used to treat cardiovascular disease, improve homeostasis, as antibacterial and anti-inflammatory agents, and as a beauty treatment. In this work, liquid chromatography coupled to hybrid linear ion trap quadrupole Orbitrap mass spectrometry was used to accurately identify persimmon leaf polyphenols. Forty-one phenolic compounds, including simple phenolic acids, hydroxybenzoic acids, hydroxycinnamic acids, flavanols, flavonols, flavanones, flavonechalcones, tyrosols and their conjugated derivatives, were identified and quantified using high mass accuracy data and confirmed by MS2 experiments. To the best of our knowledge, this is the most extensive study of persimmon leaf polyphenols performed so far, since 33 phenolic compounds are reported for the first time. (C) 2016 Elsevier Ltd. All rights reserved.This work was supported partly by CICYT (AGL2013-49083-C3-1-R) and the Instituto de Salud Carlos III, ISCIII (CIBEROBN) from the Ministerio de Economia y Competitividad (MEC) and Generalitat de Catalunya (GC) 2014 SGR 773. Paola Quifer-Rada is grateful for the predoctoral fellowships awarded by the Generalitat de Catalunya (FI-DRG). Also, the authors acknowledge the support of the Universitat Politecnica de Valencia and certify that there is no conflict of interest with any financial organisation regarding the material discussed in the manuscript.Martínez-Las Heras, R.; Quifer, R.; Andrés Grau, AM.; Lamuela-Raventós, R. (2016). Polyphenolic profile of persimmon leaves by high resolution mass spectrometry (LC-ESI-LTQ-Orbitrap-MS). Journal of Functional Foods. 23:370-377. https://doi.org/10.1016/j.jff.2016.02.048S3703772

    Immune microenvironment characterisation and dynamics during anti-HER2-based neoadjuvant treatment in HER2-positive breast cancer

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    Despite their recognised role in HER2-positive (HER2+) breast cancer (BC), the composition, localisation and functional orientation of immune cells within tumour microenvironment, as well as its dynamics during anti-HER2 treatment, is largely unknown. We here investigate changes in tumour-immune contexture, as assessed by stromal tumour-infiltrating lymphocytes (sTILs) and by multiplexed spatial cellular phenotyping, during treatment with lapatinib-trastuzumab in HER2+ BC patients (PAMELA trial). Moreover, we evaluate the relationship of tumour-immune contexture with hormone receptor status, intrinsic subtype and immune-related gene expression. sTIL levels increase after 2 weeks of HER2 blockade in HR-negative disease and HER2-enriched subtype. This is linked to a concomitant increase in cell density of all four immune subpopulations (CD3+, CD4+, CD8+, Foxp3+). Moreover, immune contexture analysis showed that immune cells spatially interacting with tumour cells have the strongest association with response to anti-HER2 treatment. Subsequently, sTILs consistently decrease at the surgery in patients achieving pathologic complete response, whereas most residual tumours at surgery remain inflamed, possibly reflecting a progressive loss of function of T cells. Understanding the features of the resulting tumour immunosuppressive microenvironment has crucial implications for the design of new strategies to de-escalate or escalate systemic therapy in early-stage HER2+ BC

    Influence of preharvest treatments to reduce the seasonality of persimmon production on color, texture and antioxidant properties during storage

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    [EN] Persimmon production has increased considerably, thanks to techniques for removing astringency whilst maintaining the strong consistency. Currently, the needs of cooperatives are focused on increasing the commercial period. Thus, the aim of this study was to analyze the effect of preharvest treatments (paclobutrazol (PBZ) and Ethephon to accelerate ripening and GA3 to delay it) on persimmon size, composition, color index (CI), texture and antioxidant properties over 11 days of postharvest storage at 4ºC. The results showed that the size of fruits subjected to preharvest treatment was smaller than in untreated fruit. Moreover, CI of the apical zone was higher in samples of standard ripening throughout the first few days of storage. It is also noteworthy that the treated fruits at the beginning of storage reported greater antioxidant properties. Finally, the evolution of the antioxidants has been fitted with a first-order model to predict their kinetic degradation depending on the persimmon harvest period.The authors thank the Universitat Politecnica de Valencia for the PhD scholarship of the author Ruth Martinez Las Heras.Martínez Las Heras, R.; Amigo-Sánchez J.C.; Heredia Gutiérrez, AB.; Castelló Gómez, ML.; Andrés Grau, AM. (2015). Influence of preharvest treatments to reduce the seasonality of persimmon production on color, texture and antioxidant properties during storage. CyTA - Journal of Food. 14(2):333-339. doi:10.1080/19476337.2015.1113204S33333914

    PRIMAGE project : predictive in silico multiscale analytics to support childhood cancer personalised evaluation empowered by imaging biomarkers

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    PRIMAGE is one of the largest and more ambitious research projects dealing with medical imaging, artificial intelligence and cancer treatment in children. It is a 4-year European Commission-financed project that has 16 European partners in the consortium, including the European Society for Paediatric Oncology, two imaging biobanks, and three prominent European paediatric oncology units. The project is constructed as an observational in silico study involving high-quality anonymised datasets (imaging, clinical, molecular, and genetics) for the training and validation of machine learning and multiscale algorithms. The open cloud-based platform will offer precise clinical assistance for phenotyping (diagnosis), treatment allocation (prediction), and patient endpoints (prognosis), based on the use of imaging biomarkers, tumour growth simulation, advanced visualisation of confidence scores, and machine-learning approaches. The decision support prototype will be constructed and validated on two paediatric cancers: neuroblastoma and diffuse intrinsic pontine glioma. External validation will be performed on data recruited from independent collaborative centres. Final results will be available for the scientific community at the end of the project, and ready for translation to other malignant solid tumours

    Acute stroke care during the COVID-19 pandemic. Ictus Madrid Program recommendations

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    La pandemia por COVID-19 ha obligado a una reorganización de los sistemas sanitarios y ha comportado una saturación excepcional de sus recursos. En este contexto es vital asegurar la atención al ictus agudo y optimizar los procesos asistenciales del código ictus para reducir el riesgo de contagios y racionalizar el uso de recursos hospitalarios. Para ello, desde el Grupo Multidisciplinar Ictus Madrid proponemos una serie de recomendaciones. Métodos Revisión bibliográfica no sistemática de las publicaciones disponibles con los términos «stroke» y «COVID-19» o «coronavirus» o «SARS-CoV-2», así como otras conocidas por los autores. En base a esta se redacta un documento de recomendaciones que es sometido a consenso por el Grupo Multidisciplinar Ictus Madrid y su Comité de Neurología. Resultados Las recomendaciones se estructuran en cinco líneas fundamentales: 1) coordinar la actuación para garantizar el acceso a la asistencia hospitalaria de los pacientes con ictus; 2) reconocer a los pacientes con ictus potencialmente infectados por COVID-19, 3) organización adecuada para garantizar la protección de los profesionales sanitarios frente al riesgo de contagio por COVID-19, 4) en la realización de neuroimagen y otros procedimientos que conlleven contactos de riesgo de infección COVID-19 hay que procurar reducirlos y asegurar la protección, y 5) alta y seguimiento seguros procurando optimizar la ocupación hospitalaria. Resumimos el procedimiento de forma esquemática con el acrónimo CORONA (COordinar, Reconocer, Organizar, Neuroimagen, Alta). Conclusiones Estas recomendaciones pueden servir de apoyo para la organización del sistema sanitario en la atención al ictus agudo y la optimización de sus recursos, garantizando la protección de sus profesionalesThe COVID-19 pandemic has forced a reorganization of healthcare systems and an exceptional saturation of their resources. In this context, it is vital to ensure acute stroke care and optimize the care processes of the stroke code to reduce the risk of contagion and rationalize the use of hospital resources. To do this, the Ictus Madrid Multidisciplinary Group proposes a series of recommendations. Methods Non-systematic bibliographic review of the available publications with the terms «stroke» and «COVID-19» or «coronavirus» or «SARS-CoV-2», as well as other already known for the authors. We provide a document of recommendations as a result of the consensus of the Ictus Madrid Multidisciplinary Group and its Neurology Committee. Results Our recommendations are structured on five lines: (1) coordinate to guarantee the access to hospital care for stroke patients, (2) recognize potentially COVID-19 infected stroke patients, (3) organize to ensure the protection of healthcare professionals from COVID-19 infections, (4) neuroimaging and other procedures potentially associated to risks for COVID-19 infection should be reduced and secured to avoid contagion, and (5) at home as soon as possible and supported follow-up to optimize hospital occupancy. The procedure is shown summarized under the acronym CORONA (COordinate, Recognize, Organize, Neuroimaging, At home). Conclusions These recommendations can support the organization of healthcare services for acute stroke care and the optimization of their resources, guaranteeing the protection of healthcare professional

    A review of the combination among global change factors in forests, shrublands and pastures of the Mediterranean Region : beyond drought effects

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    Research in CRAG is also supported byCERCA institution (Generalitat de Catalunya).Climate change, alteration of atmospheric composition, land abandonment in some areas and land use intensification in others, wildfires and biological invasions threaten forests, shrublands and pastures all over the world. However, the impacts of the combinations between global change factors are not well understood despite its pressing importance. Here we posit that reviewing global change factors combination in an exemplary region can highlight the necessary aspects in order to better understand the challenges we face, warning about the consequences, and showing the challenges ahead of us. The forests, shrublands and pastures of the Mediterranean Basin are an ideal scenario for the study of these combinations due to its spatial and temporal heterogeneity, increasing and diverse human population and the historical legacy of land use transformations. The combination of multiple global change factors in the Basin shows different ecological effects. Some interactions alter the effects of a single factor, as drought enhances or decreases the effects of atmospheric components on plant ecophysiology. Several interactions generate new impacts: drought and land use changes, among others, alter water resources and lead to land degradation, vegetation regeneration decline, and expansion of forest diseases. Finally, different factors can occur alone or simultaneously leading to further increases in the risk of fires and biological invasions. The transitional nature of the Basin between temperate and arid climates involves a risk of irreversible ecosystem change towards more arid states. However, combinations between factors lead to unpredictable ecosystem alteration that goes beyond the particular consequences of drought. Complex global change scenarios should be studied in the Mediterranean and other regions of the world, including interregional studies. Here we show the inherent uncertainty of this complexity, which should be included in any management strategy

    Zn treatment effects on biological potential of fennel bulbs as affected by in vitro digestion process

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    Zn treatment effects on the stability of polyphenols, MDA (malondialdehyde) content, antioxidant and lipoxygenase inhibition activities of two varieties of fennel bulbs were studied by using an in vitro gastrointestinal digestion model. Likewise, the effect of Zn on viability cells of E. coli was also performed. The results revealed that high amounts of total phenolic and flavonoid compounds were released during the digestion process, especially after the intestinal phase. Additionally, the antioxidant and lipoxygenase inhibitory activity were affected by the gastrointestinal digestion process and seems to be correlated with total phenol contents. On the other hand, the viability of E. coli was not affected by the activity of our tested bulbs during passage through the artificial digestion model, but the treated bulbs activity contribute relatively to the inhibition growth of bacteria. The survival of E. coli in fennel bulbs was challenged with simulated gastrointestinal fluids and the results showed that the E. coli strains, despite having experienced a viability reduction at the intestinal phase, were able to overcome the exposure to the gastrointestinal synthetic fluids. This E. coli ability reinforces the need for good hygienic measures to assure safe fresh produce, even for those that are rich in antibacterial compounds.info:eu-repo/semantics/publishedVersio
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