48 research outputs found

    Neuroadaptations in Human Chronic Alcoholics: Dysregulation of the NF-ÎșB System

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    Anna Ökvist is with Karolinska Institute, Sofia Johansson is with Karolinska Institute, Alexander Kuzmin is with Karolinska Institute, Igor Bazov is with Karolinska Institute, Roxana Merino-Martinez is with Karolinska Institute, Igor Ponomarev is with UT Austin, R. Dayne Mayfield is with UT Austin, R. Adron Harris is with UT Austin, Donna Sheedy is with University of Sydney, Therese Garrick is with University of Sydney, Clive Harper is with University of Sydney, Yasmin L. Hurd is with Mount Sinai School of Medicine, Lars Terenius is with Karolinska Institute, Tomas J. Ekström is with Karolinska Institute, Georgy Bakalkin is with Karolinska Institute and Uppsala University, Tatjana Yakovleva is with Karolinska Institute and Uppsala University.Background -- Alcohol dependence and associated cognitive impairments apparently result from neuroadaptations to chronic alcohol consumption involving changes in expression of multiple genes. Here we investigated whether transcription factors of Nuclear Factor-kappaB (NF-ÎșB) family, controlling neuronal plasticity and neurodegeneration, are involved in these adaptations in human chronic alcoholics. Methods and Findings -- Analysis of DNA-binding of NF-ÎșB (p65/p50 heterodimer) and the p50 homodimer as well as NF-ÎșB proteins and mRNAs was performed in postmortem human brain samples from 15 chronic alcoholics and 15 control subjects. The prefrontal cortex involved in alcohol dependence and cognition was analyzed and the motor cortex was studied for comparison. The p50 homodimer was identified as dominant ÎșB binding factor in analyzed tissues. NF-ÎșB and p50 homodimer DNA-binding was downregulated, levels of p65 (RELA) mRNA were attenuated, and the stoichiometry of p65/p50 proteins and respective mRNAs was altered in the prefrontal cortex of alcoholics. Comparison of a number of p50 homodimer/NF-ÎșB target DNA sites, ÎșB elements in 479 genes, down- or upregulated in alcoholics demonstrated that genes with ÎșB elements were generally upregulated in alcoholics. No significant differences between alcoholics and controls were observed in the motor cortex. Conclusions -- We suggest that cycles of alcohol intoxication/withdrawal, which may initially activate NF-ÎșB, when repeated over years downregulate RELA expression and NF-ÎșB and p50 homodimer DNA-binding. Downregulation of the dominant p50 homodimer, a potent inhibitor of gene transcription apparently resulted in derepression of ÎșB regulated genes. Alterations in expression of p50 homodimer/NF-ÎșB regulated genes may contribute to neuroplastic adaptation underlying alcoholism.This work was supported by grants from the AFA ForsĂ€kring to AK, YLH, TJE and GB, the Research Foundation of the Swedish Alcohol Retail Monopoly (SRA) and Karolinska Institutet to AK, TJE and GB, and the Swedish Science Research Council and the Swedish National Drug Policy Coordinator to GB. The Australian Brain Donor Programs NSW Tissue Resource Centre was supported by The University of Sydney, National Health and Medical Research Council of Australia, Neuroscience Institute of Schizophrenia and Allied Disorders, National Institute of Alcohol Abuse and Alcoholism and NSW Department of Health.Waggoner Center for Alcohol and Addiction Researc

    Separation of track- and shower-like energy deposits in ProtoDUNE-SP using a convolutional neural network

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    Liquid argon time projection chamber detector technology provides high spatial and calorimetric resolutions on the charged particles traversing liquid argon. As a result, the technology has been used in a number of recent neutrino experiments, and is the technology of choice for the Deep Underground Neutrino Experiment (DUNE). In order to perform high precision measurements of neutrinos in the detector, final state particles need to be effectively identified, and their energy accurately reconstructed. This article proposes an algorithm based on a convolutional neural network to perform the classification of energy deposits and reconstructed particles as track-like or arising from electromagnetic cascades. Results from testing the algorithm on data from ProtoDUNE-SP, a prototype of the DUNE far detector, are presented. The network identifies track- and shower-like particles, as well as Michel electrons, with high efficiency. The performance of the algorithm is consistent between data and simulation

    Separation of track- and shower-like energy deposits in ProtoDUNE-SP using a convolutional neural network

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    Liquid argon time projection chamber detector technology provides high spatial and calorimetric resolutions on the charged particles traversing liquid argon. As a result, the technology has been used in a number of recent neutrino experiments, and is the technology of choice for the Deep Underground Neutrino Experiment (DUNE). In order to perform high precision measurements of neutrinos in the detector, final state particles need to be effectively identified, and their energy accurately reconstructed. This article proposes an algorithm based on a convolutional neural network to perform the classification of energy deposits and reconstructed particles as track-like or arising from electromagnetic cascades. Results from testing the algorithm on experimental data from ProtoDUNE-SP, a prototype of the DUNE far detector, are presented. The network identifies track- and shower-like particles, as well as Michel electrons, with high efficiency. The performance of the algorithm is consistent between experimental data and simulation

    The Combination of Random Mutagenesis and Sequencing Highlight the Role of Unexpected Genes in an Intractable Organism

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    A large variety of organisms are capable of synthesizing hard matter in a process called biomineralization [1]. The transfor-mation of a genetic blueprint into minerals such as, for example, calcium phosphate in bones and calcium carbonate in eggs or seashells provides a mechanical support for organismic growth and protection against predators, respectively. Iron oxides formed by fishes and birds provide them with magnetic properties used for magne-toreception and orientation [2,3]. The biomineralization processes are remark-able for numerous reasons: organisms, contrary to engineers, have to form these biological materials with a limited subset of biologically available chemical ele-ments and at physiological conditions. Still, these reduced means are not at the detriment of their function, which often surpasses man-made materials based on equivalent elements [4]. Therefore, un-derstanding how biomineralizing organ-isms process chemical elements based on their genetic program is of primary interest. However, the biological mecha-nisms behind biomineralization have re-mained unclear, partly because of limited genetic knowledge: model organisms are limited to a few unicellular organisms [5,6]. Therefore, the question has arisen of what genetic approach to use to get genetic information about the large ma-jority of organisms that have remained intractable
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