ALBERT

Description: Author(s): A. Strugarek, Y. Sarazin, D. Zarzoso, J. Abiteboul, A. S. Brun, T. Cartier-Michaud, G. Dif-Pradalier, X. Garbet, Ph. Ghendrih, V. Grandgirard, G. Latu, C. Passeron, and O. Thomine The generation and dynamics of transport barriers governed by sheared poloidal flows are analyzed in flux-driven 5D gyrokinetic simulations of ion temperature gradient driven turbulence in tokamak plasmas. The transport barrier is triggered by a vorticity source that polarizes the system. The chosen... [Phys. Rev. Lett. 111, 145001] Published Wed Oct 02, 2013

Description: Author(s): J. Varela, S. Brun, B. Dubrulle, and C. Nore We present hydrodynamic and magnetohydrodynamic (MHD) simulations of liquid sodium flow with the PLUTO compressible MHD code to investigate influence of magnetic boundary conditions on the collimation of helicoidal motions. We use a simplified cartesian geometry to represent the flow dynamics in the… [Phys. Rev. E 92, 063015] Published Mon Dec 14, 2015

Description: Exploiting genotyping, DNA sequencing, imputation and trans-ancestral mapping, we used Bayesian and frequentist approaches to model the IRF5 – TNPO3 locus association, now implicated in two immunotherapies and seven autoimmune diseases. Specifically, in systemic lupus erythematosus (SLE), we resolved separate associations in the IRF5 promoter (all ancestries) and with an extended European haplotype. We captured 3230 IRF5 – TNPO3 high-quality, common variants across 5 ethnicities in 8395 SLE cases and 7367 controls. The genetic effect from the IRF5 promoter can be explained by any one of four variants in 5.7 kb ( P -value meta = 6 x 10 –49 ; OR = 1.38–1.97). The second genetic effect spanned an 85.5-kb, 24-variant haplotype that included the genes IRF5 and TNPO3 ( P -values EU = 10 –27 –10 –32 , OR = 1.7–1.81). Many variants at the IRF5 locus with previously assigned biological function are not members of either final credible set of potential causal variants identified herein. In addition to the known biologically functional variants, we demonstrated that the risk allele of rs4728142, a variant in the promoter among the lowest frequentist probability and highest Bayesian posterior probability, was correlated with IRF5 expression and differentially binds the transcription factor ZBTB3. Our analytical strategy provides a novel framework for future studies aimed at dissecting etiological genetic effects. Finally, both SLE elements of the statistical model appear to operate in Sjögren's syndrome and systemic sclerosis whereas only the IRF5–TNPO3 gene-spanning haplotype is associated with primary biliary cirrhosis, demonstrating the nuance of similarity and difference in autoimmune disease risk mechanisms at IRF5 – TNPO3 .

Description: Medulloblastoma encompasses a collection of clinically and molecularly diverse tumour subtypes that together comprise the most common malignant childhood brain tumour. These tumours are thought to arise within the cerebellum, with approximately 25% originating from granule neuron precursor cells (GNPCs) after aberrant activation of the Sonic Hedgehog pathway (hereafter, SHH subtype). The pathological processes that drive heterogeneity among the other medulloblastoma subtypes are not known, hindering the development of much needed new therapies. Here we provide evidence that a discrete subtype of medulloblastoma that contains activating mutations in the WNT pathway effector CTNNB1 (hereafter, WNT subtype) arises outside the cerebellum from cells of the dorsal brainstem. We found that genes marking human WNT-subtype medulloblastomas are more frequently expressed in the lower rhombic lip (LRL) and embryonic dorsal brainstem than in the upper rhombic lip (URL) and developing cerebellum. Magnetic resonance imaging (MRI) and intra-operative reports showed that human WNT-subtype tumours infiltrate the dorsal brainstem, whereas SHH-subtype tumours are located within the cerebellar hemispheres. Activating mutations in Ctnnb1 had little impact on progenitor cell populations in the cerebellum, but caused the abnormal accumulation of cells on the embryonic dorsal brainstem which included aberrantly proliferating Zic1(+) precursor cells. These lesions persisted in all mutant adult mice; moreover, in 15% of cases in which Tp53 was concurrently deleted, they progressed to form medulloblastomas that recapitulated the anatomy and gene expression profiles of human WNT-subtype medulloblastoma. We provide the first evidence, to our knowledge, that subtypes of medulloblastoma have distinct cellular origins. Our data provide an explanation for the marked molecular and clinical differences between SHH- and WNT-subtype medulloblastomas and have profound implications for future research and treatment of this important childhood cancer.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3059767/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3059767/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Gibson, Paul -- Tong, Yiai -- Robinson, Giles -- Thompson, Margaret C -- Currle, D Spencer -- Eden, Christopher -- Kranenburg, Tanya A -- Hogg, Twala -- Poppleton, Helen -- Martin, Julie -- Finkelstein, David -- Pounds, Stanley -- Weiss, Aaron -- Patay, Zoltan -- Scoggins, Matthew -- Ogg, Robert -- Pei, Yanxin -- Yang, Zeng-Jie -- Brun, Sonja -- Lee, Youngsoo -- Zindy, Frederique -- Lindsey, Janet C -- Taketo, Makoto M -- Boop, Frederick A -- Sanford, Robert A -- Gajjar, Amar -- Clifford, Steven C -- Roussel, Martine F -- McKinnon, Peter J -- Gutmann, David H -- Ellison, David W -- Wechsler-Reya, Robert -- Gilbertson, Richard J -- 01CA96832/CA/NCI NIH HHS/ -- P01 CA096832/CA/NCI NIH HHS/ -- P01 CA096832-06A18120/CA/NCI NIH HHS/ -- P01 CA096832-078120/CA/NCI NIH HHS/ -- P30CA021765/CA/NCI NIH HHS/ -- R01 CA129541/CA/NCI NIH HHS/ -- R01 CA129541-01/CA/NCI NIH HHS/ -- R01 CA129541-02/CA/NCI NIH HHS/ -- R01 CA129541-03/CA/NCI NIH HHS/ -- R01 CA129541-04/CA/NCI NIH HHS/ -- R01 CA129541-05/CA/NCI NIH HHS/ -- R01 NS037956/NS/NINDS NIH HHS/ -- R01 NS037956-13/NS/NINDS NIH HHS/ -- R01CA129541/CA/NCI NIH HHS/ -- England -- Nature. 2010 Dec 23;468(7327):1095-9. doi: 10.1038/nature09587. Epub 2010 Dec 8.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Developmental Neurobiology, St Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, Tennessee 38105, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21150899" target="_blank"〉PubMed〈/a〉

Description: Epigenetic alterations, that is, disruption of DNA methylation and chromatin architecture, are now acknowledged as a universal feature of tumorigenesis. Medulloblastoma, a clinically challenging, malignant childhood brain tumour, is no exception. Despite much progress from recent genomics studies, with recurrent changes identified in each of the four distinct tumour subgroups (WNT-pathway-activated, SHH-pathway-activated, and the less-well-characterized Group 3 and Group 4), many cases still lack an obvious genetic driver. Here we present whole-genome bisulphite-sequencing data from thirty-four human and five murine tumours plus eight human and three murine normal controls, augmented with matched whole-genome, RNA and chromatin immunoprecipitation sequencing data. This comprehensive data set allowed us to decipher several features underlying the interplay between the genome, epigenome and transcriptome, and its effects on medulloblastoma pathophysiology. Most notable were highly prevalent regions of hypomethylation correlating with increased gene expression, extending tens of kilobases downstream of transcription start sites. Focal regions of low methylation linked to transcription-factor-binding sites shed light on differential transcriptional networks between subgroups, whereas increased methylation due to re-normalization of repressed chromatin in DNA methylation valleys was positively correlated with gene expression. Large, partially methylated domains affecting up to one-third of the genome showed increased mutation rates and gene silencing in a subgroup-specific fashion. Epigenetic alterations also affected novel medulloblastoma candidate genes (for example, LIN28B), resulting in alternative promoter usage and/or differential messenger RNA/microRNA expression. Analysis of mouse medulloblastoma and precursor-cell methylation demonstrated a somatic origin for many alterations. Our data provide insights into the epigenetic regulation of transcription and genome organization in medulloblastoma pathogenesis, which are probably also of importance in a wider developmental and disease context.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hovestadt, Volker -- Jones, David T W -- Picelli, Simone -- Wang, Wei -- Kool, Marcel -- Northcott, Paul A -- Sultan, Marc -- Stachurski, Katharina -- Ryzhova, Marina -- Warnatz, Hans-Jorg -- Ralser, Meryem -- Brun, Sonja -- Bunt, Jens -- Jager, Natalie -- Kleinheinz, Kortine -- Erkek, Serap -- Weber, Ursula D -- Bartholomae, Cynthia C -- von Kalle, Christof -- Lawerenz, Chris -- Eils, Jurgen -- Koster, Jan -- Versteeg, Rogier -- Milde, Till -- Witt, Olaf -- Schmidt, Sabine -- Wolf, Stephan -- Pietsch, Torsten -- Rutkowski, Stefan -- Scheurlen, Wolfram -- Taylor, Michael D -- Brors, Benedikt -- Felsberg, Jorg -- Reifenberger, Guido -- Borkhardt, Arndt -- Lehrach, Hans -- Wechsler-Reya, Robert J -- Eils, Roland -- Yaspo, Marie-Laure -- Landgraf, Pablo -- Korshunov, Andrey -- Zapatka, Marc -- Radlwimmer, Bernhard -- Pfister, Stefan M -- Lichter, Peter -- England -- Nature. 2014 Jun 26;510(7506):537-41. doi: 10.1038/nature13268. Epub 2014 May 18.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2]. ; 1] Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2]. ; Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany. ; Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany. ; Max Planck Institute for Molecular Genetics, Ihnestrasse 63-73, Berlin 14195, Germany. ; Department of Pediatric Oncology, Hematology and Clinical Immunology, Heinrich Heine University Dusseldorf, Moorenstrasse 5, Dusseldorf 40225, Germany. ; Department of Neuropathology, NN Burdenko Neurosurgical Institute, 4th Tverskaya-Yamskaya 16, Moscow 125047, Russia. ; Tumor Initiation and Maintenance Program, National Cancer Institute (NCI)-Designated Cancer Center, Sanford-Burnham Medical Research Institute, 2880 Torrey Pines Scenic Drive, La Jolla, California 92037, USA. ; 1] Queensland Brain Institute, University of Queensland, QBI Building, St Lucia, Queensland 4072, Australia [2] Department of Oncogenomics, AMC, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, the Netherlands. ; Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany. ; 1] Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany. ; 1] Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, Heidelberg 69117, Germany. ; 1] Division of Translational Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] National Center for Tumor Diseases (NCT), Im Neuenheimer Feld 460, Heidelberg 69120, Germany. ; Data Management Facility, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany. ; Department of Oncogenomics, AMC, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, the Netherlands. ; 1] Department of Pediatric Oncology, Hematology & Immunology, Heidelberg University Hospital, Im Neuenheimer Feld 430, Heidelberg 69120, Germany [2] Clinical Cooperation Unit Pediatric Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany. ; Genomics and Proteomics Core Facility, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany. ; Department of Neuropathology, University of Bonn Medical Center, Sigmund-Freud-Strasse 25, Bonn 53105, Germany. ; Department of Paediatric Haematology and Oncology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, Hamburg 20246, Germany. ; Cnopf'sche Kinderklinik, Nurnberg Children's Hospital, St.-Johannis-Muhlgasse 19, Nurnberg 90419, Germany. ; 1] Program in Developmental and Stem Cell Biology, The Arthur and Sonia Labatt Brain Tumour Research Centre, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada [2] Division of Neurosurgery, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada [3] Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada. ; 1] Department of Neuropathology, Heinrich Heine University Dusseldorf, Moorenstrasse 5, Dusseldorf 40225, Germany [2] German Consortium for Translational Cancer Research (DKTK), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany. ; 1] Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] Institute of Pharmacy and Molecular Biotechnology (IPMB), University of Heidelberg, Heidelberg 69120, Germany [3] Bioquant Center, University of Heidelberg, Im Neuenheimer Feld 267, Heidelberg 69120, Germany [4] Heidelberg Center for Personalised Oncology (DKFZ-HIPO), Im Neuenheimer Feld 280, Heidelberg 69120, Germany. ; 1] Department of Neuropathology, University of Heidelberg, Im Neuenheimer Feld 220, Heidelberg 69120, Germany [2] Clinical Cooperation Unit Neuropathology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 220-221, Heidelberg, 69120 Germany. ; 1] Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] Department of Pediatric Oncology, Hematology & Immunology, Heidelberg University Hospital, Im Neuenheimer Feld 430, Heidelberg 69120, Germany. ; 1] Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] Heidelberg Center for Personalised Oncology (DKFZ-HIPO), Im Neuenheimer Feld 280, Heidelberg 69120, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24847876" target="_blank"〉PubMed〈/a〉

Description: Fluvial bedrock incision sets the pace of landscape evolution and can be dominated by abrasion from impacting particles. Existing bedrock incision models diverge on the ability of sediment to erode within the suspension regime, leading to competing predictions of lowland river erosion rates, knickpoint formation and evolution, and the transient response of orogens to external forcing. We present controlled abrasion mill experiments designed to test fluvial incision models in the bedload and suspension regimes by varying sediment size while holding fixed hydraulics, sediment load, and substrate strength. Measurable erosion occurred within the suspension regime, and erosion rates agree with a mechanistic incision theory for erosion by mixed suspended and bedload sediment. Our experimental results indicate that suspension-regime erosion can dominate channel incision during large floods and in steep channels, with significant implications for the pace of landscape evolution.

Description: 〈p〉Intelligent machines using machine learning algorithms are ubiquitous, ranging from simple data analysis and pattern recognition tools to complex systems that achieve superhuman performance on various tasks. Ensuring that they do not exhibit undesirable behavior—that they do not, for example, cause harm to humans—is therefore a pressing problem. We propose a general and flexible framework for designing machine learning algorithms. This framework simplifies the problem of specifying and regulating undesirable behavior. To show the viability of this framework, we used it to create machine learning algorithms that precluded the dangerous behavior caused by standard machine learning algorithms in our experiments. Our framework for designing machine learning algorithms simplifies the safe and responsible application of machine learning.〈/p〉