150 research outputs found

    Improving plastic management by means of people awareness

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    In past decades the usage of plastic has seen a tremendous increment. This raise is mainly caused by industrial development and by the spread of this material in every aspect of people life, from food package to aerospace application. For sure plastic has a key role in society and it is not possible to erase, nevertheless its overuse has a serious impact on the environment as well know. In particular, just a few percentage of the total amount of plastic is recycled, the rest has to be landfilled or burnt causing serious pollution side effect. This poor circularity in plastic value chain is mainly caused by difficulties in sorting processes and expensiveness of recycling. By the way a great part of plastic applications could be avoided without implying a reduction in life quality for the people. In addition, a better education in plastic objects shopping and plastic waste management could decrease the difficulties in sorting and recycling. One of the crucial reason why these applications and incorrect behaviour are still present is that the information on alternatives are not present or very hard to be found. In the present paper a novel platform to enhance a more plastic-free life is presented. First a detailed description of the problem is stated, then the process to achieve the proposed solution is described. Finally the platform prototype is analysed in details among its functionalities

    Studying the vertical extent of the ground layer turbulence using sonic-anemometers

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    The optical turbulence above Dome C in winter is mainly concentrated in the first tens of meters above the ground. The properties of this so-called surface layer were investigated during the last two winterover by a set of sonics anemometers placed on a 45 m high tower. These anemometers provide measurements of the temperature and the wind speed vector. The sampling rate of 10 Hz allows to derivate the refractive index structure constant C_n^2. We report here the first analysis of these data

    Calcium Signalling Triggered by NAADP in T Cells Determines Cell Shape and Motility During Immune Synapse Formation

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    Nicotinic acid adenine dinucleotide phosphate (NAADP) has been implicated as an initial Ca(2+) trigger in T cell Ca(2+) signalling, but its role in formation of the immune synapse in CD4(+) effector T cells has not been analysed. CD4(+) T cells are activated by the interaction with peptide-MHCII complexes on the surface of antigen-presenting cells. Establishing a two-cell system including primary rat CD4(+) T cells specific for myelin basic protein and rat astrocytes enabled us to mirror this activation process in vitro and to analyse Ca(2+) signalling, cell shape changes and motility in T cells during formation and maintenance of the immune synapse. After immune synapse formation, T cells showed strong, antigen-dependent increases in free cytosolic calcium concentration ([Ca(2+)](i)). Analysis of cell shape and motility revealed rounding and immobilization of T cells depending on the amplitude of the Ca(2+) signal. NAADP-antagonist BZ194 effectively blocked Ca(2+) signals in T cells evoked by the interaction with antigen-presenting astrocytes. BZ194 reduced the percentage of T cells showing high Ca(2+) signals thereby supporting the proposed trigger function of NAADP for global Ca(2+) signalling. Taken together, the NAADP signalling pathway is further confirmed as a promising target for specific pharmacological intervention to modulate T cell activation

    Nicotinic acid adenine dinucleotide phosphate-mediated calcium signalling in effector T cells regulates autoimmunity of the central nervous system

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    Nicotinic acid adenine dinucleotide phosphate represents a newly identified second messenger in T cells involved in antigen receptor-mediated calcium signalling. Its function in vivo is, however, unknown due to the lack of biocompatible inhibitors. Using a recently developed inhibitor, we explored the role of nicotinic acid adenine dinucleotide phosphate in autoreactive effector T cells during experimental autoimmune encephalomyelitis, the animal model for multiple sclerosis. We provide in vitro and in vivo evidence that calcium signalling controlled by nicotinic acid adenine dinucleotide phosphate is relevant for the pathogenic potential of autoimmune effector T cells. Live two photon imaging and molecular analyses revealed that nicotinic acid adenine dinucleotide phosphate signalling regulates T cell motility and re-activation upon arrival in the nervous tissues. Treatment with the nicotinic acid adenine dinucleotide phosphate inhibitor significantly reduced both the number of stable arrests of effector T cells and their invasive capacity. The levels of pro-inflammatory cytokines interferon-gamma and interleukin-17 were strongly diminished. Consecutively, the clinical symptoms of experimental autoimmune encephalomyelitis were ameliorated. In vitro, antigen-triggered T cell proliferation and cytokine production were evenly suppressed. These inhibitory effects were reversible: after wash-out of the nicotinic acid adenine dinucleotide phosphate antagonist, the effector T cells fully regained their functions. The nicotinic acid derivative BZ194 induced this transient state of non-responsiveness specifically in post-activated effector T cells. Naïve and long-lived memory T cells, which express lower levels of the putative nicotinic acid adenine dinucleotide phosphate receptor, type 1 ryanodine receptor, were not targeted. T cell priming and recall responses in vivo were not reduced. These data indicate that the nicotinic acid adenine dinucleotide phosphate/calcium signalling pathway is essential for the recruitment and the activation of autoaggressive effector T cells within their target organ. Interference with this signalling pathway suppresses the formation of autoimmune inflammatory lesions and thus might qualify as a novel strategy for the treatment of T cell mediated autoimmune diseases

    Dietary cholesterol promotes repair of demyelinated lesions in the adult brain

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    Multiple Sclerosis (MS) is an inflammatory demyelinating disorder in which remyelination failure contributes to persistent disability. Cholesterol is rate-limiting for myelin biogenesis in the developing CNS; however, whether cholesterol insufficiency contributes to remyelination failure in MS, is unclear. Here, we show the relationship between cholesterol, myelination and neurological parameters in mouse models of demyelination and remyelination. In the cuprizone model, acute disease reduces serum cholesterol levels that can be restored by dietary cholesterol. Concomitant with blood-brain barrier impairment, supplemented cholesterol directly supports oligodendrocyte precursor proliferation and differentiation, and restores the balance of growth factors, creating a permissive environment for repair. This leads to attenuated axon damage, enhanced remyelination and improved motor learning. Remarkably, in experimental autoimmune encephalomyelitis, cholesterol supplementation does not exacerbate disease expression. These findings emphasize the safety of dietary cholesterol in inflammatory diseases and point to a previously unrecognized role of cholesterol in promoting repair after demyelinating episodes

    Ultralow Temperature Studies of Nanometer Size Semiconductor Devices

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    Contains a description on one research project.Joint Services Electronics Program DAAL03-89-C-000

    The Activation Status of Neuroantigen-specific T Cells in the Target Organ Determines the Clinical Outcome of Autoimmune Encephalomyelitis

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    The clinical picture of experimental autoimmune encephalomyelitis (EAE) is critically dependent on the nature of the target autoantigen and the genetic background of the experimental animals. Potentially lethal EAE is mediated by myelin basic protein (MBP)–specific T cells in Lewis rats, whereas transfer of S100β- or myelin oligodendrocyte glycoprotein (MOG)–specific T cells causes intense inflammatory response in the central nervous system (CNS) with minimal disease. However, in Dark Agouti rats, the pathogenicity of MOG-specific T cells resembles the one of MBP-specific T cells in the Lewis rat. Using retrovirally transduced green fluorescent T cells, we now report that differential disease activity reflects different levels of autoreactive effector T cell activation in their target tissue. Irrespective of their pathogenicity, the migratory activity, gene expression patterns, and immigration of green fluorescent protein+ T cells into the CNS were similar. However, exclusively highly pathogenic T cells were significantly reactivated within the CNS. Without local effector T cell activation, production of monocyte chemoattractants was insufficient to initiate and propagate a full inflammatory response. Low-level reactivation of weakly pathogenic T cells was not due to anergy because these cells could be activated by specific antigen in situ as well as after isolation ex vivo

    Ketogenic diet uncovers differential metabolic plasticity of brain cells

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    To maintain homeostasis, the body, including the brain, reprograms its metabolism in response to altered nutrition or disease. However, the consequences of these challenges for the energy metabolism of the different brain cell types remain unknown. Here, we generated a proteome atlas of the major central nervous system (CNS) cell types from young and adult mice, after feeding the therapeutically relevant low-carbohydrate, high-fat ketogenic diet (KD) and during neuroinflammation. Under steady-state conditions, CNS cell types prefer distinct modes of energy metabolism. Unexpectedly, the comparison with KD revealed distinct cell type–specific strategies to manage the altered availability of energy metabolites. Astrocytes and neurons but not oligodendrocytes demonstrated metabolic plasticity. Moreover, inflammatory demyelinating disease changed the neuronal metabolic signature in a similar direction as KD. Together, these findings highlight the importance of the metabolic cross-talk between CNS cells and between the periphery and the brain to manage altered nutrition and neurological disease

    M tuberculosis in the adjuvant modulates time of appearance of CNS-specific effector T cells in the spleen through a polymorphic site of TLR2

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    DC deliver information regulating trafficking of effector T cells along T-cell priming. However, the role of pathogen-derived motives in the regulation of movement of T cells has not been studied. We hereinafter report that amount of M tuberculosis in the adjuvant modulates relocation of PLP139-151 specific T cells. In the presence of a low dose of M tuberculosis in the adjuvant, T cells (detected by CDR3 BV-BJ spectratyping, the so-called "immunoscope") mostly reach the spleen by day 28 after immunization ("late relocation") in the SJL strain, whereas T cells reach the spleen by d 14 with a high dose of M tuberculosis ("early relocation"). The C57Bl/6 background confers a dominant "early relocation" phenotype to F1 (SJL 7C57Bl/6) mice, allowing early relocation of T cells in the presence of low dose M tuberculosis. A single non-synonymous polymorphism of TLR2 is responsible for "early/late" relocation phenotype. Egress of T lymphocytes is regulated by TLR2 expressed on T cells. Thus, pathogens engaging TLR2 on T cells regulate directly T-cell trafficking, and polymorphisms of TLR2 condition T-cell trafficking upon a limiting concentration of ligand
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