290 resultados para Morgan, Carolyn
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We performed a meta-analysis of 14 genome-wide association studies of coronary artery disease (CAD) comprising 22,233 individuals with CAD (cases) and 64,762 controls of European descent followed by genotyping of top association signals in 56,682 additional individuals. This analysis identified 13 loci newly associated with CAD at P < 5 x 10(-8) and confirmed the association of 10 of 12 previously reported CAD loci. The 13 new loci showed risk allele frequencies ranging from 0.13 to 0.91 and were associated with a 6% to 17% increase in the risk of CAD per allele. Notably, only three of the new loci showed significant association with traditional CAD risk factors and the majority lie in gene regions not previously implicated in the pathogenesis of CAD. Finally, five of the new CAD risk loci appear to have pleiotropic effects, showing strong association with various other human diseases or traits.
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Background: Late Onset Alzheimer's disease (LOAD) is the leading cause of dementia. Recent large genome-wide association studies (GWAS) identified the first strongly supported LOAD susceptibility genes since the discovery of the involvement of APOE in the early 1990s. We have now exploited these GWAS datasets to uncover key LOAD pathophysiological processes. Methodology: We applied a recently developed tool for mining GWAS data for biologically meaningful information to a LOAD GWAS dataset. The principal findings were then tested in an independent GWAS dataset.
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We sought to identify new susceptibility loci for Alzheimer's disease through a staged association study (GERAD+) and by testing suggestive loci reported by the Alzheimer's Disease Genetic Consortium (ADGC) in a companion paper. We undertook a combined analysis of four genome-wide association datasets (stage 1) and identified ten newly associated variants with P = 1 × 10(-5). We tested these variants for association in an independent sample (stage 2). Three SNPs at two loci replicated and showed evidence for association in a further sample (stage 3). Meta-analyses of all data provided compelling evidence that ABCA7 (rs3764650, meta P = 4.5 × 10(-17); including ADGC data, meta P = 5.0 × 10(-21)) and the MS4A gene cluster (rs610932, meta P = 1.8 × 10(-14); including ADGC data, meta P = 1.2 × 10(-16)) are new Alzheimer's disease susceptibility loci. We also found independent evidence for association for three loci reported by the ADGC, which, when combined, showed genome-wide significance: CD2AP (GERAD+, P = 8.0 × 10(-4); including ADGC data, meta P = 8.6 × 10(-9)), CD33 (GERAD+, P = 2.2 × 10(-4); including ADGC data, meta P = 1.6 × 10(-9)) and EPHA1 (GERAD+, P = 3.4 × 10(-4); including ADGC data, meta P = 6.0 × 10(-10)).
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We conducted a genome-wide association study testing single nucleotide polymorphisms (SNPs) and copy number variants (CNVs) for association with early-onset myocardial infarction in 2,967 cases and 3,075 controls. We carried out replication in an independent sample with an effective sample size of up to 19,492. SNPs at nine loci reached genome-wide significance: three are newly identified (21q22 near MRPS6-SLC5A3-KCNE2, 6p24 in PHACTR1 and 2q33 in WDR12) and six replicated prior observations1-4 (9p21, 1p13 near CELSR2-PSRC1-SORT1, 10q11 near CXCL12, 1q41 in MIA3, 19p13 near LDLR and 1p32 near PCSK9). We tested 554 common copy number polymorphisms (>1% allele frequency) and none met the pre-specified threshold for replication (P < 10-3). We identified 8,065 rare CNVs but did not detect a greater CNV burden in cases compared to controls, in genes compared to the genome as a whole, or at any individual locus. SNPs at nine loci were reproducibly associated with myocardial infarction, but tests of common and rare CNVs failed to identify additional associations with myocardial infarction risk.
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Today, the classification systems for myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) already incorporate cytogenetic and molecular genetic aberrations in an attempt to better reflect disease biology. However, in many MDS/AML patients no genetic aberrations have been identified yet, and even within some cytogenetically well-defined subclasses there is considerable clinical heterogeneity. Recent advances in genomics technologies such as gene expression profiling (GEP) provide powerful tools to further characterize myeloid malignancies at the molecular level, with the goal to refine the MDS/AML classification system, incorporating as yet unknown molecular genetic and epigenetic pathomechanisms, which are likely reflected by aberrant gene expression patterns. In this study, we provide a comprehensive review on how GEP has contributed to a refined molecular taxonomy of MDS and AML with regard to diagnosis, prediction of clinical outcome, discovery of novel subclasses and identification of novel therapeutic targets and novel drugs. As many challenges remain ahead, we discuss the pitfalls of this technology and its potential including future integrative studies with other genomics technologies, which will continue to improve our understanding of malignant transformation in myeloid malignancies and thereby contribute to individualized risk-adapted treatment strategies for MDS and AML patients. Leukemia (2011) 25, 909-920; doi:10.1038/leu.2011.48; published online 29 March 2011
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A recently published genome-wide association study (GWAS) of late-onset Alzheimer's disease (LOAD) revealed genome-wide significant association of variants in or near MS4A4A, CD2AP, EPHA1 and CD33. Meta-analyses of this and a previously published GWAS revealed significant association at ABCA7 and MS4A, independent evidence for association of CD2AP, CD33 and EPHA1 and an opposing yet significant association of a variant near ARID5B. In this study, we genotyped five variants (in or near CD2AP, EPHA1, ARID5B, and CD33) in a large (2,634 LOAD, 4,201 controls), independent dataset comprising six case-control series from the USA and Europe. We performed meta-analyses of the association of these variants with LOAD and tested for association using logistic regression adjusted by age-at-diagnosis, gender, and APOE e4 dosage.
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We sought to investigate the contribution of extended runs of homozygosity in a genome-wide association dataset of 1,955 Alzheimer's disease cases and 955 elderly screened controls genotyped for 529,205 autosomal single nucleotide polymorphisms. Tracts of homozygosity may mark regions inherited from a common ancestor and could reflect disease loci if observed more frequently in cases than controls. We found no excess of homozygous tracts in Alzheimer's disease cases compared to controls and no individual run of homozygosity showed association to Alzheimer's disease.
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All TAP micro-reactor configurations contain inert particles which are used so that the catalyst zone can be maintained under isothermal conditions. Even on
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We present photometric and spectroscopic observations of a luminous Type IIP Supernova (SN) 2009kf discovered by the Pan-STARRS 1 (PS1) survey and also detected by the Galaxy Evolution Explorer. The SN shows a plateau in its optical and bolometric light curves, lasting approximately 70 days in the rest frame, with an absolute magnitude of M-V = - 18.4 mag. The P-Cygni profiles of hydrogen indicate expansion velocities of 9000 km s(-1) at 61 days after discovery which is extremely high for a Type IIP SN. SN 2009kf is also remarkably bright in the near-ultraviolet (NUV) and shows a slow evolution 10-20 days after optical discovery. The NUV and optical luminosity at these epochs can be modeled with a blackbody with a hot effective temperature (T similar to 16,000 K) and a large radius (R similar to 1 x 10(15) cm). The bright bolometric and NUV luminosity, the light curve peak and plateau duration, the high velocities, and temperatures suggest that 2009kf is a Type IIP SN powered by a larger than normal explosion energy. Recently discovered high-z SNe (0.7
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We present an extensive set of photometric and spectroscopic data for SN 2009jf, a nearby Type Ib supernova (SN), spanning from ˜20 d before B-band maximum to 1 yr after maximum. We show that SN 2009jf is a slowly evolving and energetic stripped-envelope SN and is likely from a massive progenitor (25-30 Msun). The large progenitor's mass allows us to explain the complete hydrogen plus helium stripping without invoking the presence of a binary companion. The SN occurred close to a young cluster, in a crowded environment with ongoing star formation. The spectroscopic similarity with the He-poor Type Ic SN 2007gr suggests a common progenitor for some SNe Ib and Ic. The nebular spectra of SN 2009jf are consistent with an asymmetric explosion, with an off-centre dense core. We also find evidence that He-rich Ib SNe have a rise time longer than other stripped-envelope SNe, however confirmation of this result and further observations are needed. This paper is based on observations with several telescopes, including NTT(184.D-1151), VLT-UT1(085.D-0750,386.D-0126), NOT, WHT, TNG, PROMPT, Ekar, Calar Alto and Liverpool Telescope.
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We present the detection of the putative progenitor of the Type IIb SN 2011dh in archival pre-explosion Hubble Space Telescope images. Using post-explosion Adaptive Optics imaging with Gemini NIRI+ALTAIR, the position of the supernova (SN) in the pre-explosion images was determined to within 23 mas. The progenitor candidate is consistent with an F8 supergiant star (logL/L sun = 4.92 ± 0.20 and T eff = 6000 ± 280 K). Through comparison with stellar evolution tracks, this corresponds to a single star at the end of core C-burning with an initial mass of M ZAMS = 13 ± 3 M sun. The possibility of the progenitor source being a cluster is rejected, on the basis of: (1) the source not being spatially extended, (2) the absence of excess Ha emission, and (3) the poor fit to synthetic cluster spectral energy distributions (SEDs). It is unclear if a binary companion is contributing to the observed SED, although given the excellent correspondence of the observed photometry to a single star SED we suggest that the companion does not contribute significantly. Early photometric and spectroscopic observations show fast evolution similar to the transitional Type IIb SN 2008ax and suggest that a large amount of the progenitor's hydrogen envelope was removed before explosion. Late-time observations will reveal if the yellow supergiant or the putative companion star were responsible for this SN explosion.
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Heavy metals, primarily zinc, copper, lead, and chromium, and Polycyclic Aromatic Hydrocarbons (PAHs) are the main hazardous constituents of road runoff. The main sources of these contaminants are vehicle emission, mostly through wear and leakage, although erosion of the road surface and de-icing salts are also recognised pollution sources. The bioavailability of these toxic compounds, and more importantly their potential biomagnification along food chains, could affect aquatic communities persistently exposed to road runoff. Several internationally approved abatement technologies are available for the management of road runoff on new motorway schemes. Recent studies conducted in Cork and Dublin, Ireland demonstrated the efficacy of infiltration trenches as abatement technologies in the removal of both heavy metals and PAHs prior to discharge; the technology was however inefficient in mitigating first flush events. Gully traps with sedimentation chambers, another technology investigated, demonstrated to have a substantially lower removal potential but appeared to be more effective in attenuating surges of contaminants attributed to first flush events. Consequently the employment of combined abatement techniques could efficiently minimise deviations from required effluent concentrations. The studies determined a relatively stationary accumulation of heavy metals and PAHs in sediments close to the point of discharge with a rapid decline in concentration in nearby downstream sediments (<50m). Further, Microtox® Solid Phase testing reported a negligible impact on assemblages exposed to contaminated sediments for all sites investigated. This paper describes pollutant loading from road runoff and mitigation measures from a freshwater deterioration in a water quality perspective. The results and analysis of field samples collected adjacent to a number of roads and motorways in Ireland is also presented. Finally sustainable drainage systems, abatement techniques and technologies available for onsite treatment of runoff are presented to improve and mitigate impacts of vehicular transport on the environment.