2,168 research outputs found

    Considerations for using potential surrogate endpoints in cancer screening trials.

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    The requirement of large-scale expensive cancer screening trials spanning decades creates considerable barriers to the development, commercialisation, and implementation of novel screening tests. One way to address these problems is to use surrogate endpoints for the ultimate endpoint of interest, cancer mortality, at an earlier timepoint. This Review aims to highlight the issues underlying the choice and use of surrogate endpoints for cancer screening trials, to propose criteria for when and how we might use such endpoints, and to suggest possible candidates. We present the current landscape and challenges, and discuss lessons and shortcomings from the therapeutic trial setting. It is hugely challenging to validate a surrogate endpoint, even with carefully designed clinical studies. Nevertheless, we consider whether there are candidates that might satisfy the requirements defined by research and regulatory bodies

    A genome-wide association study to identify genetic markers associated with endometrial cancer grade

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    RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

    Dynamic modelling shows substantial contribution of ecosystem restoration to climate change mitigation

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    This is the final version. Available from the Global Systems Institute, University of Exeter via the link in this recordGSI scientific working paper series number 2021/02Limiting global warming to a 1.5°C temperature rise requires drastic emissions reductions and removal of carbon dioxide from the atmosphere. Most modelled pathways for 1.5°C assume substantial removals in the form of biomass energy with carbon capture and storage, which brings with it increasing risks to biodiversity and food security via extensive land-use change. Recently, multiple efforts to describe and quantify potential removals via ecosystem-based approaches have gained traction in the climate policy discourse. However, these options have yet to be evaluated in a systematic and scientifically robust way. We provide spatially explicit estimates of ecosystem restoration potential quantified with a Dynamic Global Vegetation Model. Simulations covering forest restoration, reforestation, reduced harvest, agroforestry and silvopasture were combined and found to sequester an additional 93 Gt C by 2100, reducing mean global temperature increase by ~0.12°C (5-95% range 0.06-0.21°C) relative to a baseline mitigation pathway. Ultimately, pathways to achieving the 1.5°C goal garner broader public support when they include land management options that can bring about multiple benefits, including ecosystem restoration, biodiversity protection, and resilient agricultural practices

    Myanmar Burkholderia pseudomallei strains are genetically diverse and originate from Asia with phylogenetic evidence of reintroductions from neighbouring countries.

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    Melioidosis was first identified in Myanmar in 1911 but for the last century it has remained largely unreported there. Burkholderia pseudomallei was first isolated from the environment of Myanmar in 2016, confirming continuing endemicity. Recent genomic studies showed that B. pseudomallei originated in Australia and spread to Asia, with phylogenetic evidence of repeated reintroduction of B. pseudomallei across countries bordered by the Mekong River and the Malay Peninsula. We present the first whole-genome sequences of B. pseudomallei isolates from Myanmar: nine clinical and seven environmental isolates. We used large-scale comparative genomics to assess the genetic diversity, phylogeography and potential origins of B. pseudomallei in Myanmar. Global phylogenetics demonstrated that Myanmar isolates group in two distantly related clades that reside in a more ancestral Asian clade with high amounts of genetic diversity. The diversity of B. pseudomallei from Myanmar and divergence within our global phylogeny suggest that the original introduction of B. pseudomallei to Myanmar was not a recent event. Our study provides new insights into global patterns of B. pseudomallei dissemination, most notably the dynamic nature of movement of B. pseudomallei within densely populated Southeast Asia. The role of anthropogenic influences in both ancient and more recent dissemination of B. pseudomallei to Myanmar and elsewhere in Southeast Asia and globally requires further study

    Risk and prognostic factors for endometrial carcinoma after diagnosis of breast or Lynch‐associated cancers—A population‐based analysis

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    We hypothesized that endometrial carcinoma (EC) patients with a prior cancer diagnosis, after accounting for EC arising after tamoxifen‐treated prior breast carcinoma, are more likely to have an underlying genetic basis. We used information from a population‐based study to compare measured risk factors, tumor characteristics, survival, and known mismatch repair (MMR) pathogenic variant status for EC subgroups according to prior diagnosis of cancer (none, breast cancer tamoxifen‐treated or not, Lynch Syndrome (LS)‐associated cancer). Family history of any cancer was increased for EC cases with prior breast cancer, both tamoxifen treated (P = 0.005) and untreated (P = 0.01). EC cases with prior LS‐associated cancer more often reported family history of LS‐associated cancer (P = 0.04) and breast cancer (P = 0.05). EC patients with a germline pathogenic MMR gene variant were more likely to report a prior cancer than cases with a MMR proficient tumor (P = 0.0001), but more than half (54.5%) of MMR carriers reported no prior cancer. Women developing EC after tamoxifen treatment for breast cancer were significantly more likely to develop EC of malignant mixed mullerian tumor subtype (13.2% vs 2.6%, P = 1.3 × 10^{-6}), present with stage IV disease (8.8% vs 1.2%, P = 1.6 × 10^{-6}), and have poorer survival (HR_{adj} 1.96; P = 0.001). While report of prior cancer is an indicator of MMR pathogenic variant status, molecular analysis of all ECs at diagnosis is warranted to detect all patients with LS. Results also indicate the importance of longer‐term monitoring of women treated with tamoxifen for symptoms of EC, and the need for studies assessing the biological mechanism underlying the poorer prognosis of this subset of EC patients

    Survival and dispersal of a defined cohort of Irish cattle

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    An understanding of livestock movement is critical to effective disease prevention, control and prediction. However, livestock movement in Ireland has not yet been quantified. This study has sought to define the survival and dispersal of a defined cohort of cattle born in Co. Kerry during 2000. The cohort was observed for a maximum of four years, from January 1, 2000 to December 31, 2004. Beef and dairy animals moved an average 1.31 and 0.83 times, respectively. At study end, 18.8% of the beef animals remained alive on Irish farms, including 6.7% at the farm-of-birth, compared with 48.6% and 27.7% for dairy animals respectively. Beef animals werae dispersed to all Irish counties, but mainly to Cork, Limerick, Tipperary and Galway. Dairy animals mainly moved to Cork, Limerick, and Tipperary, with less animals going to Galway, Meath and Kilkenny. The four-year survival probability was 0.07 (male beef animals), 0.25 (male dairy), 0.38 (female beef), and 0.72 (female dairy). Although there was considerable dispersal, the number of moves per animal was less than expected

    Using Land Runoff to Survey the Distribution and Genetic Diversity of Burkholderia pseudomallei in Vientiane, Laos.

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    Melioidosis is a disease of significant public health importance that is being increasingly recognized globally. The majority of cases arise through direct percutaneous exposure to its etiological agent, Burkholderia pseudomallei In the Lao People's Democratic Republic (Laos), the presence and environmental distribution of B. pseudomallei are not well characterized, though recent epidemiological surveys of the bacterium have indicated that B. pseudomallei is widespread throughout the environment in the center and south of the country and that rivers can act as carriers and potential sentinels for the bacterium. The spatial and genetic distribution of B. pseudomallei within Vientiane Capital, from where the majority of cases diagnosed to date have originated, remains an important knowledge gap. We sampled surface runoff from drain catchment areas throughout urban Vientiane to determine the presence and local population structure of the bacterium. B. pseudomallei was detected in drainage areas throughout the capital, indicating it is widespread in the environment and that exposure rates in urban Vientiane are likely more frequent than previously thought. Whole-genome comparative analysis demonstrated that Lao B. pseudomallei isolates are highly genetically diverse, suggesting the bacterium is well-established and not a recent introduction. Despite the wide genome diversity, one environmental survey isolate was highly genetically related to a Lao melioidosis patient isolate collected 13?years prior to the study. Knowledge gained from this study will augment understanding of B. pseudomallei phylogeography in Asia and enhance public health awareness and future implementation of infection control measures within Laos.IMPORTANCE The environmental bacterium B. pseudomallei is the etiological agent of melioidosis, a tropical disease with one model estimating a global annual incidence of 165,000 cases and 89,000 deaths. In the Lao People's Democratic Republic (Laos), the environmental distribution and population structure of B. pseudomallei remain relatively undefined, particularly in Vientiane Capital from where most diagnosed cases have originated. We used surface runoff as a proxy for B. pseudomallei dispersal in the environment and performed whole-genome sequencing (WGS) to examine the local population structure. Our data confirmed that B. pseudomallei is widespread throughout Vientiane and that surface runoff might be useful for future environmental monitoring of the bacterium. B. pseudomallei isolates were also highly genetically diverse, suggesting the bacterium is well-established and endemic in Laos. These findings can be used to improve awareness of B. pseudomallei in the Lao environment and demonstrates the epidemiological and phylogeographical insights that can be gained from WGS

    Evidence for a population of high-redshift submillimeter galaxies from interferometric imaging

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    We have used the Submillimeter Array to image a flux-limited sample of seven submillimeter galaxies, selected by the AzTEC camera on the JCMT at 1.1 mm, in the COSMOS field at 890 μ m with ~2\u27\u27 resolution. All of the sources—two radio-bright and five radio-dim—are detected as single point sources at high significance (\u3e6 σ), with positions accurate to ~0.2\u27\u27 that enable counterpart identification at other wavelengths observed with similarly high angular resolution. All seven have IRAC counterparts, but only two have secure counterparts in deep HST ACS imaging. As compared to the two radio-bright sources in the sample, and those in previous studies, the five radio-dim sources in the sample (1) have systematically higher submillimeter-to-radio flux ratios, (2) have lower IRAC 3.6-8.0 μ m fluxes, and (3) are not detected at 24 μ m . These properties, combined with size constraints at 890 μ m (θ 1.2\u27\u27), suggest that the radio-dim submillimeter galaxies represent a population of very dusty starbursts, with physical scales similar to local ultraluminous infrared galaxies, with an average redshift higher than radio-bright sources

    Identification of Giardia lamblia DHHC Proteins and the Role of Protein S-palmitoylation in the Encystation Process

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    Protein S-palmitoylation, a hydrophobic post-translational modification, is performed by protein acyltransferases that have a common DHHC Cys-rich domain (DHHC proteins), and provides a regulatory switch for protein membrane association. In this work, we analyzed the presence of DHHC proteins in the protozoa parasite Giardia lamblia and the function of the reversible S-palmitoylation of proteins during parasite differentiation into cyst. Two specific events were observed: encysting cells displayed a larger amount of palmitoylated proteins, and parasites treated with palmitoylation inhibitors produced a reduced number of mature cysts. With bioinformatics tools, we found nine DHHC proteins, potential protein acyltransferases, in the Giardia proteome. These proteins displayed a conserved structure when compared to different organisms and are distributed in different monophyletic clades. Although all Giardia DHHC proteins were found to be present in trophozoites and encysting cells, these proteins showed a different intracellular localization in trophozoites and seemed to be differently involved in the encystation process when they were overexpressed. dhhc transgenic parasites showed a different pattern of cyst wall protein expression and yielded different amounts of mature cysts when they were induced to encyst. Our findings disclosed some important issues regarding the role of DHHC proteins and palmitoylation during Giardia encystation.Fil: Merino, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; ArgentinaFil: Zamponi, Nahuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; ArgentinaFil: Vranych, Cecilia Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; ArgentinaFil: Touz, Maria Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; ArgentinaFil: Ropolo, Andrea Silvana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentin
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