55 research outputs found

    The clinical application of PET/CT: a contemporary review

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    The combination of positron emission tomography (PET) scanners and x-ray computed tomography (CT) scanners into a single PET/CT scanner has resulted in vast improvements in the diagnosis of disease, particularly in the field of oncology. A decade on from the publication of the details of the first PET/CT scanner, we review the technology and applications of the modality. We examine the design aspects of combining two different imaging types into a single scanner, and the artefacts produced such as attenuation correction, motion and CT truncation artefacts. The article also provides a discussion and literature review of the applications of PET/CT to date, covering detection of tumours, radiotherapy treatment planning, patient management, and applications external to the field of oncology

    Key Lessons Learned from Moffitt's Molecular Tumor Board: The Clinical Genomics Action Committee Experience

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    The increasing practicality of genomic sequencing technology has led to its incorporation into routine clinical practice. Successful identification and targeting of driver genomic alterations that provide proliferative and survival advantages to tumor cells have led to approval and ongoing development of several targeted cancer therapies. Within many major cancer centers, molecular tumor boards are constituted to shepherd precision medicine into clinical practice

    Carbon on the Northwest European Shelf: Contemporary Budget and Future Influences

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    A carbon budget for the northwest European continental shelf seas (NWES) was synthesized using available estimates for coastal, pelagic and benthic carbon stocks and flows. Key uncertainties were identified and the effect of future impacts on the carbon budget were assessed. The water of the shelf seas contains between 210 and 230 Tmol of carbon and absorbs between 1.3 and 3.3 Tmol from the atmosphere annually. Off-shelf transport and burial in the sediments account for 60–100 and 0–40% of carbon outputs from the NWES, respectively. Both of these fluxes remain poorly constrained by observations and resolving their magnitudes and relative importance is a key research priority. Pelagic and benthic carbon stocks are dominated by inorganic carbon. Shelf sediments contain the largest stock of carbon, with between 520 and 1600 Tmol stored in the top 0.1 m of the sea bed. Coastal habitats such as salt marshes and mud flats contain large amounts of carbon per unit area but their total carbon stocks are small compared to pelagic and benthic stocks due to their smaller spatial extent. The large pelagic stock of carbon will continue to increase due to the rising concentration of atmospheric CO2, with associated pH decrease. Pelagic carbon stocks and flows are also likely to be significantly affected by increasing acidity and temperature, and circulation changes but the net impact is uncertain. Benthic carbon stocks will be affected by increasing temperature and acidity, and decreasing oxygen concentrations, although the net impact of these interrelated changes on carbon stocks is uncertain and a major knowledge gap. The impact of bottom trawling on benthic carbon stocks is unique amongst the impacts we consider in that it is widespread and also directly manageable, although its net effect on the carbon budget is uncertain. Coastal habitats are vulnerable to sea level rise and are strongly impacted by management decisions. Local, national and regional actions have the potential to protect or enhance carbon storage, but ultimately global governance, via controls on emissions, has the greatest potential to influence the long-term fate of carbon stocks in the northwestern European continental shelf

    Magnetite in Comet Wild 2: Evidence for parent body aqueous alteration

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    The mineralogy of comet 81P/Wild 2 particles, collected in aerogel by the Stardust mission, has been determined using synchrotron Fe-K X-ray absorption spectroscopy with insitu transmission XRD and X-ray fluorescence, plus complementary microRaman analyses. Our investigation focuses on the terminal grains of eight Stardust tracks: C2112,4,170,0,0; C2045,2,176,0,0; C2045,3,177,0,0; C2045,4,178,0,0; C2065,4,187,0,0; C2098,4,188,0,0; C2119,4,189,0,0; and C2119,5,190,0,0. Three terminal grains have been identified as near pure magnetite Fe3O4. The presence of magnetite shows affinities between the Wild 2 mineral assemblage and carbonaceous chondrites, and probably resulted from hydrothermal alteration of the coexisting FeNi and ferromagnesian silicates in the cometary parent body. In order to further explore this hypothesis, powdered material from a CR2 meteorite (NWA 10256) was shot into the aerogel at 6.1kms(-1), using a light-gas gun, and keystones were then prepared in the same way as the Stardust keystones. Using similar analysis techniques to the eight Stardust tracks, a CR2 magnetite terminal grain establishes the likelihood of preserving magnetite during capture in silica aeroge

    Carbon on the Northwest European Shelf: Contemporary Budget and Future Influences

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    © Copyright © 2020 Legge, Johnson, Hicks, Jickells, Diesing, Aldridge, Andrews, Artioli, Bakker, Burrows, Carr, Cripps, Felgate, Fernand, Greenwood, Hartman, Kröger, Lessin, Mahaffey, Mayor, Parker, Queirós, Shutler, Silva, Stahl, Tinker, Underwood, Van Der Molen, Wakelin, Weston and Williamson. A carbon budget for the northwest European continental shelf seas (NWES) was synthesized using available estimates for coastal, pelagic and benthic carbon stocks and flows. Key uncertainties were identified and the effect of future impacts on the carbon budget were assessed. The water of the shelf seas contains between 210 and 230 Tmol of carbon and absorbs between 1.3 and 3.3 Tmol from the atmosphere annually. Off-shelf transport and burial in the sediments account for 60–100 and 0–40% of carbon outputs from the NWES, respectively. Both of these fluxes remain poorly constrained by observations and resolving their magnitudes and relative importance is a key research priority. Pelagic and benthic carbon stocks are dominated by inorganic carbon. Shelf sediments contain the largest stock of carbon, with between 520 and 1600 Tmol stored in the top 0.1 m of the sea bed. Coastal habitats such as salt marshes and mud flats contain large amounts of carbon per unit area but their total carbon stocks are small compared to pelagic and benthic stocks due to their smaller spatial extent. The large pelagic stock of carbon will continue to increase due to the rising concentration of atmospheric CO2, with associated pH decrease. Pelagic carbon stocks and flows are also likely to be significantly affected by increasing acidity and temperature, and circulation changes but the net impact is uncertain. Benthic carbon stocks will be affected by increasing temperature and acidity, and decreasing oxygen concentrations, although the net impact of these interrelated changes on carbon stocks is uncertain and a major knowledge gap. The impact of bottom trawling on benthic carbon stocks is unique amongst the impacts we consider in that it is widespread and also directly manageable, although its net effect on the carbon budget is uncertain. Coastal habitats are vulnerable to sea level rise and are strongly impacted by management decisions. Local, national and regional actions have the potential to protect or enhance carbon storage, but ultimately global governance, via controls on emissions, has the greatest potential to influence the long-term fate of carbon stocks in the northwestern European continental shelf

    Raman identification of olivine grains in fine grained mineral assemblages fired into aerogel

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    NASA’s Stardust mission returned from the comet 81P/Wild2 in 2006 and has yielded a plethora of research looking into the composition and attributes of the comet. The mission itself collected thousands of cometary dust particles as it flew through the coma of the comet at a relative speed of 6.1 km s-1. This work focuses on one of the most abundant minerals in the solar system – olivine. Previous work has shown capture affects on this mineral in similar impacts to that experienced during the Stardust mission. However, the past work looked into effects on isolated mineral grains which would be a rare occurrence in the Solar System. A more accurate representation of this would be to investigate the capture effects on olivine as a constituent of an assemblage of minerals. Accordingly, here we used samples from the NWA 10256 CR2 carbonaceous chondrite meteorite. This natural sample contains fine grains of olivine, and brings additional issues when analysing the olivine due to limited homogeneity. Shifts in the Raman spectra for olivine, enstatite and hematite were observed after capture due to shock effects. However, this work suggests that olivine may well experience a different shock effect during capture when part of a mineral assemblage as distinct from that experienced by single grains

    Effects of human footprint and biophysical factors on the body-size structure of fished marine species

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    Marine fisheries in coastal ecosystems in many areas of the world have historically removed large-bodied individuals, potentially impairing ecosystem functioning and the long-term sustainability of fish populations. Reporting on size-based indicators that link to food-web structure can contribute to ecosystem-based management, but the application of these indicators over large (cross-ecosystem) geographical scales has been limited to either fisheries-dependent catch data or diver-based methods restricted to shallow waters (<20 m) that can misrepresent the abundance of large-bodied fished species. We obtained data on the body-size structure of 82 recreationally or commercially targeted marine demersal teleosts from 2904 deployments of baited remote underwater stereo-video (stereo-BRUV). Sampling was at up to 50 m depth and covered approximately 10,000 km of the continental shelf of Australia. Seascape relief, water depth, and human gravity (i.e., a proxy of human impacts) were the strongest predictors of the probability of occurrence of large fishes and the abundance of fishes above the minimum legal size of capture. No-take marine reserves had a positive effect on the abundance of fishes above legal size, although the effect varied across species groups. In contrast, sublegal fishes were best predicted by gradients in sea surface temperature (mean and variance). In areas of low human impact, large fishes were about three times more likely to be encountered and fishes of legal size were approximately five times more abundant. For conspicuous species groups with contrasting habitat, environmental, and biogeographic affinities, abundance of legal-size fishes typically declined as human impact increased. Our large-scale quantitative analyses highlight the combined importance of seascape complexity, regions with low human footprint, and no-take marine reserves in protecting large-bodied fishes across a broad range of species and ecosystem configurations.publishedVersio

    ErbB3 downregulation enhances luminal breast tumor response to antiestrogens

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    Aberrant regulation of the erythroblastosis oncogene B (ErbB) family of receptor tyrosine kinases (RTKs) and their ligands is common in human cancers. ErbB3 is required in luminal mammary epithelial cells (MECs) for growth and survival. Since breast cancer phenotypes may reflect biological traits of the MECs from which they originate, we tested the hypothesis that ErbB3 drives luminal breast cancer growth. We found higher ERBB3 expression and more frequent ERBB3 gene copy gains in luminal A/B breast cancers compared with other breast cancer subtypes. In cell culture, ErbB3 increased growth of luminal breast cancer cells. Targeted depletion of ErbB3 with an anti-ErbB3 antibody decreased 3D colony growth, increased apoptosis, and decreased tumor growth in vivo. Treatment of clinical breast tumors with the antiendocrine drug fulvestrant resulted in increased ErbB3 expression and PI3K/mTOR signaling. Depletion of ErbB3 in fulvestrant-treated tumor cells reduced PI3K/mTOR signaling, thus decreasing tumor cell survival and tumor growth. Fulvestrant treatment increased phosphorylation of all ErbB family RTKs; however, phospho-RTK upregulation was not seen in tumors treated with both fulvestrant and anti-ErbB3. These data indicate that upregulation of ErbB3 in luminal breast cancer cells promotes growth, survival, and resistance to fulvestrant, thus suggesting ErbB3 as a target for breast cancer treatment

    ErbB3 downregulation enhances luminal breast tumor response to antiestrogens

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    Aberrant regulation of the erythroblastosis oncogene B (ErbB) family of receptor tyrosine kinases (RTKs) and their ligands is common in human cancers. ErbB3 is required in luminal mammary epithelial cells (MECs) for growth and survival. Since breast cancer phenotypes may reflect biological traits of the MECs from which they originate, we tested the hypothesis that ErbB3 drives luminal breast cancer growth. We found higher ERBB3 expression and more frequent ERBB3 gene copy gains in luminal A/B breast cancers compared with other breast cancer subtypes. In cell culture, ErbB3 increased growth of luminal breast cancer cells. Targeted depletion of ErbB3 with an anti-ErbB3 antibody decreased 3D colony growth, increased apoptosis, and decreased tumor growth in vivo. Treatment of clinical breast tumors with the antiendocrine drug fulvestrant resulted in increased ErbB3 expression and PI3K/mTOR signaling. Depletion of ErbB3 in fulvestrant-treated tumor cells reduced PI3K/mTOR signaling, thus decreasing tumor cell survival and tumor growth. Fulvestrant treatment increased phosphorylation of all ErbB family RTKs; however, phospho-RTK upregulation was not seen in tumors treated with both fulvestrant and anti-ErbB3. These data indicate that upregulation of ErbB3 in luminal breast cancer cells promotes growth, survival, and resistance to fulvestrant, thus suggesting ErbB3 as a target for breast cancer treatment

    Automated workflow-based exploitation of pathway databases provides new insights into genetic associations of metabolite profiles

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    Background: Genome-wide association studies (GWAS) have identified many common single nucleotide polymorphisms (SNPs) that associate with clinical phenotypes, but these SNPs usually explain just a small part of the heritability and have relatively modest effect sizes. In contrast, SNPs that associate with metabolite levels generally explain a higher percentage of the genetic variation and demonstrate larger effect sizes. Still, the discovery of SNPs associated with metabolite levels is challenging since testing all metabolites measured in typical metabolomics studies with all SNPs comes with a severe multiple testing penalty. We have developed an automated workflow approach that utilizes prior knowledge of biochemical pathways present in databases like KEGG and BioCyc to generate a smaller SNP set relevant to the metabolite. This paper explores the opportunities and challenges in the analysis of GWAS of metabolomic phenotypes and provides novel insights into the genetic basis of metabolic variation through the re-analysis of published GWAS datasets. Results: Re-analysis of the published GWAS dataset from Illig et al. (Nature Genetics, 2010) using a pathway-based workflow (http://www.myexperiment.org/packs/319.html), confirmed previously identified hits and identified a new locus of human metabolic individuality, associating Aldehyde dehydrogenase family1 L1 (ALDH1L1) with serine/glycine ratios in blood. Replication in an independent GWAS dataset of phospholipids (Demirkan et al., PLoS Genetics, 2012) identified two novel loci supported by additional literature evidence: GPAM (Glycerol-3 phosphate acyltransferase) and CBS (Cystathionine beta-synthase). In addition, the workflow approach provided novel insight into the affected pathways and relevance of some of these gene-metabolite pairs in disease development and progression. Conclusions: We demonstrate the utility of automated exploitation of background knowledge present in pathway databases for the analysis of GWAS datasets of metabolomic phenotypes. We report novel loci and potential biochemical mechanisms that contribute to our understanding of the genetic basis of metabolic variation and its relationship to disease development and progression
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