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Claudia Emanuele Carvalho-Sousa Eliana P. Pereira Gabriela S. Kinker Mariana Veras Zulma S. Ferreira Fernanda P. Barbosa-Nunes Joilson O. Martins Paulo H.N. Saldiva Russel J. Reiter Pedro A. Fernandes Sanseray da Silveira Cruz-Machado Regina P. Markus 《Journal of pineal research》2020,68(3):e12636
Environmental pollution in the form of particulate matter <2.5 μm (PM2.5) is a major risk factor for diseases such as lung cancer, chronic respiratory infections, and major cardiovascular diseases. Our goal was to show that PM2.5 eliciting a proinflammatory response activates the immune-pineal axis, reducing the pineal synthesis and increasing the extrapineal synthesis of melatonin. Herein, we report that the exposure of rats to polluted air for 6 hours reduced nocturnal plasma melatonin levels and increased lung melatonin levels. Melatonin synthesis in the lung reduced lipid peroxidation and increased PM2.5 engulfment and cell viability by activating high-affinity melatonin receptors. Diesel exhaust particles (DEPs) promoted the synthesis of melatonin in a cultured cell line (RAW 264.7 cells) and rat alveolar macrophages via the expression of the gene encoding for AANAT through a mechanism dependent on activation of the NFκB pathway. Expression of the genes encoding AANAT, MT1, and MT2 was negatively correlated with cellular necroptosis, as disclosed by analysis of Gene Expression Omnibus (GEO) microarray data from the human alveolar macrophages of nonsmoking subjects. The enrichment score for antioxidant genes obtained from lung gene expression data (GTEx) was significantly correlated with the levels of AANAT and MT1 but not the MT2 melatonin receptor. Collectively, these data provide a systemic and mechanistic rationale for coordination of the pineal and extrapineal synthesis of melatonin by a standard damage-associated stimulus, which activates the immune-pineal axis and provides a new framework for understanding the effects of air pollution on lung diseases. 相似文献
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Huang Sicong He Xintong Doyle Tracy J. Zaccardelli Alessandra Marshall Allison A. Friedlander H. Maura Blaustein Rachel B. Smith Elisabeth A. Cui Jing Iannaccone Christine K. Mahmoud Taysir G. Weinblatt Michael E. Dellaripa Paul F. Shadick Nancy A. Sparks Jeffrey A. 《Clinical rheumatology》2020,39(4):1371-1372
Clinical Rheumatology - The publisher regrets that the two sections under the Results omitted inadvertently on the original published version of the above article. 相似文献
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Rusman Tamara John Marie-Luise B. van der Weijden Mignon A. C. Boden Bouke J. H. van der Bijl Carmella M. A. Bruijnen Stefan T. G. van der Laken Conny J. Nurmohamed Mike T. van der Horst-Bruinsma Irene E. 《Clinical rheumatology》2020,39(5):1521-1529
Clinical Rheumatology - The primary aim is to evaluate signs of inflammation on MRI of sacroiliac joints (SIJ)/spine in inflammatory back pain (IBP) patients suspected of nr-axSpA with high disease... 相似文献
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Klemm Philipp Hudowenz Ole Asendorf Thomas Dischereit Gabriel Müller-Ladner Ulf Lange Uwe Tarner Ingo H. 《Clinical rheumatology》2020,39(5):1513-1520
Clinical Rheumatology - Multimodal rheumatologic complex treatment (MRCT) is a specific concept of German inpatient care focusing on physical therapy for patients with rheumatic diseases suffering... 相似文献
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Xin‐Lu Cai Dong‐Jie Xie Kristoffer H. Madsen Yong‐Ming Wang Sophie Alida Bgemann Eric F. C. Cheung Arne Mller Raymond C. K. Chan 《Human brain mapping》2020,41(1):172-184
Machine learning has increasingly been applied to classification of schizophrenia in neuroimaging research. However, direct replication studies and studies seeking to investigate generalizability are scarce. To address these issues, we assessed within‐site and between‐site generalizability of a machine learning classification framework which achieved excellent performance in a previous study using two independent resting‐state functional magnetic resonance imaging data sets collected from different sites and scanners. We established within‐site generalizability of the classification framework in the main data set using cross‐validation. Then, we trained a model in the main data set and investigated between‐site generalization in the validated data set using external validation. Finally, recognizing the poor between‐site generalization performance, we updated the unsupervised algorithm to investigate if transfer learning using additional unlabeled data were able to improve between‐site classification performance. Cross‐validation showed that the published classification procedure achieved an accuracy of 0.73 using majority voting across all selected components. External validation found a classification accuracy of 0.55 (not significant) and 0.70 (significant) using the direct and transfer learning procedures, respectively. The failure of direct generalization from one site to another demonstrates the limitation of within‐site cross‐validation and points toward the need to incorporate efforts to facilitate application of machine learning across multiple data sets. The improvement in performance with transfer learning highlights the importance of taking into account the properties of data when constructing predictive models across samples and sites. Our findings suggest that machine learning classification result based on a single study should be interpreted cautiously. 相似文献
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