73 research outputs found

    OPENMENDEL: A Cooperative Programming Project for Statistical Genetics

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    Statistical methods for genomewide association studies (GWAS) continue to improve. However, the increasing volume and variety of genetic and genomic data make computational speed and ease of data manipulation mandatory in future software. In our view, a collaborative effort of statistical geneticists is required to develop open source software targeted to genetic epidemiology. Our attempt to meet this need is called the OPENMENDELproject (https://openmendel.github.io). It aims to (1) enable interactive and reproducible analyses with informative intermediate results, (2) scale to big data analytics, (3) embrace parallel and distributed computing, (4) adapt to rapid hardware evolution, (5) allow cloud computing, (6) allow integration of varied genetic data types, and (7) foster easy communication between clinicians, geneticists, statisticians, and computer scientists. This article reviews and makes recommendations to the genetic epidemiology community in the context of the OPENMENDEL project.Comment: 16 pages, 2 figures, 2 table

    DHODH modulates transcriptional elongation in the neural crest and melanoma

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    Melanoma is a tumour of transformed melanocytes, which are originally derived from the embryonic neural crest. It is unknown to what extent the programs that regulate neural crest development interact with mutations in the BRAF oncogene, which is the most commonly mutated gene in human melanoma1. We have used zebrafish embryos to identify the initiating transcriptional events that occur on activation of human BRAF(V600E) (which encodes an amino acid substitution mutant of BRAF) in the neural crest lineage. Zebrafish embryos that are transgenic for mitfa:BRAF(V600E) and lack p53 (also known as tp53) have a gene signature that is enriched for markers of multipotent neural crest cells, and neural crest progenitors from these embryos fail to terminally differentiate. To determine whether these early transcriptional events are important for melanoma pathogenesis, we performed a chemical genetic screen to identify small-molecule suppressors of the neural crest lineage, which were then tested for their effects on melanoma. One class of compound, inhibitors of dihydroorotate dehydrogenase (DHODH), for example leflunomide, led to an almost complete abrogation of neural crest development in zebrafish and to a reduction in the self-renewal of mammalian neural crest stem cells. Leflunomide exerts these effects by inhibiting the transcriptional elongation of genes that are required for neural crest development and melanoma growth. When used alone or in combination with a specific inhibitor of the BRAF(V600E) oncogene, DHODH inhibition led to a marked decrease in melanoma growth both in vitro and in mouse xenograft studies. Taken together, these studies highlight developmental pathways in neural crest cells that have a direct bearing on melanoma formation

    Microbial Community Dynamics of Lactate Enriched Hanford Groundwaters

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    The Department of Energy site at Hanford, WA, has been historically impacted by U and Cr from the nuclear weapons industry. In an attempt to stimulate microbial remediation of these metals, in-situ lactate enrichment experiments are ongoing. In order to bridge the gap from the laboratory to the field, we inoculated triplicate anaerobic, continuous-flow glass reactors with groundwater collected from well Hanford 100-H in order to obtain a stable, enriched community while selecting for metal-reducing bacteria. Each reactor was fed from a single carboy containing defined media with 30 mM lactate at a rate of 0.223 ml/min under continuous nitrogen flow at 9 ml/min. Cell counts, organic acids, gDNA (for qPCR and pyrosequencing) and gases were sampled during the experiment. Cell counts remained low (less than 1x107 cells/ml) during the first two weeks of the experiment, but by day 20, had reached a density greater than 1x108 cells/ml. Metabolite analysis showed a decrease in the lactate concentrations over time. Pyruvate concentrations ranged from 20-40 uM the first week of the experiment then was undetectable after day 10. Likewise, formate appeared in the reactors during the first week with concentrations of 1.48-1.65 mM at day 7 then the concentrations decreased to 0.69-0.95 on day 10 and were undetectable on day 15. Acetate was present in low amounts on day 3 (0.15-0.33 mM) and steadily increased to 3.35-5.22 mM over time. Similarly, carbon dioxide was present in low concentrations early on and increased to 0.28-0.35 mM as the experiment progressed. We also were able to detect low amounts of methane (10-20 uM) during the first week of the experiment, but by day 10 the methane was undetectable. From these results and pyrosequencing analysis, we conclude that a shift in the microbial community dynamics occurred over time to eventually form a stable and enriched microbial community. Comprehensive investigations such as these allow for the examination of not only which nutrient source will accelerate site remediation, but also provide insight to evaluate remediation strategies through which enriched community members are important for bioremediation

    Plasma fibronectin supports hemostasis and regulates thrombosis

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    Plasma fibronectin (pFn) has long been suspected to be involved in hemostasis; however, direct evidence has been lacking. Here, we demonstrated that pFn is vital to control bleeding in fibrinogen-deficient mice and in WT mice given anticoagulants. At the site of vessel injury, pFn was rapidly deposited and initiated hemostasis, even before platelet accumulation, which is considered the first wave of hemostasis. This pFn deposition was independent of fibrinogen, von Willebrand factor, β3 integrin, and platelets. Confocal and scanning electron microscopy revealed pFn integration into fibrin, which increased fibrin fiber diameter and enhanced the mechanical strength of clots, as determined by thromboelastography. Interestingly, pFn promoted platelet aggregation when linked with fibrin but inhibited this process when fibrin was absent. Therefore, pFn may gradually switch from supporting hemostasis to inhibiting thrombosis and vessel occlusion following the fibrin gradient that decreases farther from the injured endothelium. Our data indicate that pFn is a supportive factor in hemostasis, which is vital under both genetic and therapeutic conditions of coagulation deficiency. By interacting with fibrin and platelet β3 integrin, pFn plays a self-limiting regulatory role in thrombosis, suggesting pFn transfusion may be a potential therapy for bleeding disorders, particularly in association with anticoagulant therapy

    Integrative taxonomy and phylogeography of Colomys and Nilopegamys (Rodentia: Murinae), semi-aquatic mice of Africa, with descriptions of two new species

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    The semi-aquatic African murine genera Colomys and Nilopegamys are considered monotypic and thought to be closely related to one another. Colomys occurs across forested regions of equatorial Africa, whereas Nilopegamys is known only from the Ethiopian holotype, making it among the rarest mammalian genera in the world – and possibly extinct. Using morphological and genetic data, we reassess the taxonomy of Colomys and Nilopegamys. A multilocus phylogeny with outgroups demonstrates that Nilopegamys is sister to Colomys. In addition, we recognize at least four morphologically diagnosable and genetically distinct species within Colomys: C. eisentrauti (elevated from subspecies and restricted to north-west Cameroon), C. goslingi (with a more restricted range than previously reported) and two new species (one from Liberia and Guinea and one from central and southern Democratic Republic of the Congo and Angola). We also review the status of four other taxa currently recognized within Colomys goslingi (bicolor, denti, goslingi and ruandensis) and demonstrate that these names lack phylogenetic and/or morphological support. Finally, we discuss potential biogeographic barriers that may have played a role in the evolution of Colomys and Nilopegamys, emphasizing the importance of rivers in both facilitating and, possibly, limiting dispersal within these genera.https://academic.oup.com/zoolinneanhj2022Mammal Research InstituteZoology and Entomolog

    Economic and social changes among distressed family caregivers of lung cancer patients

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    Although costs of lung cancer care have been documented, economic and social changes among lung cancer patients’ family caregivers have yet to be fully examined. In addition, research has not focused on caregivers with greater need for support services. This study examined various economic and social changes among distressed family caregivers of lung cancer patients during the initial months of cancer care in the United States

    Characterization of Human Osteoarthritic Cartilage Using Optical and Magnetic Resonance Imaging

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    Purpose: Osteoarthritis (OA) is a degenerative disease starting with key molecular events that ultimately lead to the breakdown of the cartilage. The purpose of this study is to use two imaging methods that are sensitive to molecular and macromolecular changes in OA to better characterize the disease process in human osteoarthritic cartilage. Procedures: Human femoral condyles were collected from patients diagnosed with severe OA during total knee replacement surgeries. T1ρ and T2 magnetic resonance measurements were obtained using a 3-Tesla whole body scanner to assess macromolecular changes in the damaged cartilage matrix. Optical imaging was performed on specimens treated with MMPSense 680 to assess the matrix metalloproteinase (MMP) activity. A linear regression model was used to assess the correlation of MMP optical data with T 1ρ magnetic resonance (MR) measurements. Slices from a representative specimen were removed from regions with high and low optical signals for subsequent histological analysis. Results: All specimens exhibit high T1ρ and T2 measurements in the range of 48–75 ms and 36– 69 ms, respectively. They also show intense photon signals (0.376 to 7.89×10 −4 cm 2) from th

    Somatosensory System Deficits in Schizophrenia Revealed by MEG during a Median-Nerve Oddball Task

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    Although impairments related to somatosensory perception are common in schizophrenia, they have rarely been examined in functional imaging studies. In the present study, magnetoencephalography (MEG) was used to identify neural networks that support attention to somatosensory stimuli in healthy adults and abnormalities in these networks in patient with schizophrenia. A median-nerve oddball task was used to probe attention to somatosensory stimuli, and an advanced, high-resolution MEG source-imaging method was applied to assess activity throughout the brain. In nineteen healthy subjects, attention-related activation was seen in a sensorimotor network involving primary somatosensory (S1), secondary somatosensory (S2), primary motor (M1), pre-motor (PMA), and paracentral lobule (PCL) areas. A frontal–parietal–temporal “attention network”, containing dorsal- and ventral–lateral prefrontal cortex (DLPFC and VLPFC), orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), superior parietal lobule (SPL), inferior parietal lobule (IPL)/supramarginal gyrus (SMG), and temporal lobe areas, was also activated. Seventeen individuals with schizophrenia showed early attention-related hyperactivations in S1 and M1 but hypo-activation in S1, S2, M1, and PMA at later latency in the sensorimotor network. Within this attention network, hypoactivation was found in SPL, DLPFC, orbitofrontal cortex, and the dorsal aspect of ACC. Hyperactivation was seen in SMG/IPL, frontal pole, and the ventral aspect of ACC in patients. These findings link attention-related somatosensory deficits to dysfunction in both sensorimotor and frontal–parietal–temporal networks in schizophrenia

    Inverting the model of genomics data sharing with the NHGRI Genomic Data Science Analysis, Visualization, and Informatics Lab-space

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    The NHGRI Genomic Data Science Analysis, Visualization, and Informatics Lab-space (AnVIL; https://anvilproject.org) was developed to address a widespread community need for a unified computing environment for genomics data storage, management, and analysis. In this perspective, we present AnVIL, describe its ecosystem and interoperability with other platforms, and highlight how this platform and associated initiatives contribute to improved genomic data sharing efforts. The AnVIL is a federated cloud platform designed to manage and store genomics and related data, enable population-scale analysis, and facilitate collaboration through the sharing of data, code, and analysis results. By inverting the traditional model of data sharing, the AnVIL eliminates the need for data movement while also adding security measures for active threat detection and monitoring and provides scalable, shared computing resources for any researcher. We describe the core data management and analysis components of the AnVIL, which currently consists of Terra, Gen3, Galaxy, RStudio/Bioconductor, Dockstore, and Jupyter, and describe several flagship genomics datasets available within the AnVIL. We continue to extend and innovate the AnVIL ecosystem by implementing new capabilities, including mechanisms for interoperability and responsible data sharing, while streamlining access management. The AnVIL opens many new opportunities for analysis, collaboration, and data sharing that are needed to drive research and to make discoveries through the joint analysis of hundreds of thousands to millions of genomes along with associated clinical and molecular data types
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