56 research outputs found

    Redlining−associated methylation in breast tumors: the impact of contemporary structural racism on the tumor epigenome

    Get PDF
    PurposePlace-based measures of structural racism have been associated with breast cancer mortality, which may be driven, in part, by epigenetic perturbations. We examined the association between contemporary redlining, a measure of structural racism at the neighborhood level, and DNA methylation in breast tumor tissue.MethodsWe identified 80 Black and White women diagnosed and treated for a first-primary breast cancer at Emory University Hospitals (2008–2017). Contemporary redlining was derived for census tracts using the Home Mortgage Disclosure Act database. Linear regression models were used to calculate the association between contemporary redlining and methylation in breast tumor tissue. We also examined epigenetic age acceleration for two different metrics, regressing ÎČ values for each cytosine-phosphate-guanine dinucleotide (CpG) site on redlining while adjusting for covariates. We employed multivariable Cox-proportional hazards models and 95% confidence intervals (CI) to estimate the association between aberrant methylation and mortality.ResultsContemporary redlining was associated with 5 CpG sites after adjustment for multiple comparisons (FDR<0.10). All genes were implicated in breast carcinogenesis, including genes related to inflammation, immune function and stress response (ANGPT1, PRG4 and PRG4). Further exploration of the top 25 CpG sites, identified interaction of 2 sites (MRPS28 and cg11092048) by ER status and 1 site (GDP1) was associated with all-cause mortality. Contemporary redlining was associated with epigenetic age acceleration by the Hannum metric (ÎČ=5.35; CI 95%=0.30,10.4) and showed positive but non-significant correlation with the other clock.ConclusionWe identified novel associations between neighborhood contemporary redlining and the breast tumor DNA methylome, suggesting that racist policies leading to inequitable social and environmental exposures, may impact the breast tumor epigenome. Additional research on the potential implications for prognosis is needed

    Expectancy and Treatment Interactions: A Dissociation between Acupuncture Analgesia and Expectancy Evoked Placebo Analgesia

    Get PDF
    Recent advances in placebo research have demonstrated the mind's power to alter physiology. In this study, we combined an expectancy manipulation model with both verum and sham acupuncture treatments to address: 1) how and to what extent treatment and expectancy effects — including both subjective pain intensity levels (pain sensory ratings) and objective physiological activations (fMRI) — interact; and 2) if the underlying mechanism of expectancy remains the same whether placebo treatment is given alone or in conjunction with active treatment. The results indicate that although verum acupuncture + high expectation and sham acupuncture + high expectation induced subjective reports of analgesia of equal magnitude, fMRI analysis showed that verum acupuncture produced greater fMRI signal decrease in pain related brain regions during application of calibrated heat pain stimuli on the right arm. We believe our study provides brain imaging evidence for the existence of different mechanisms underlying acupuncture analgesia and expectancy evoked placebo analgesia. Our results also suggest that the brain network involved in expectancy may vary under different treatment situations (verum and sham acupuncture treatment).National Center for Complementary and Alternative Medicine (U.S.) (PO1-AT002048)National Center for Complementary and Alternative Medicine (U.S.) (R21AT00949

    Methyl Complexes of the Transition Metals

    Get PDF
    Organometallic chemistry can be considered as a wide area of knowledge that combines concepts of classic organic chemistry, that is, based essentially on carbon, with molecular inorganic chemistry, especially with coordination compounds. Transition-metal methyl complexes probably represent the simplest and most fundamental way to view how these two major areas of chemistry combine and merge into novel species with intriguing features in terms of reactivity, structure, and bonding. Citing more than 500 bibliographic references, this review aims to offer a concise view of recent advances in the field of transition-metal complexes containing M-CH fragments. Taking into account the impressive amount of data that are continuously provided by organometallic chemists in this area, this review is mainly focused on results of the last five years. After a panoramic overview on M-CH compounds of Groups 3 to 11, which includes the most recent landmark findings in this area, two further sections are dedicated to methyl-bridged complexes and reactivity.Ministerio de Ciencia e InnovaciĂłn Projects CTQ2010–15833, CTQ2013-45011 - P and Consolider - Ingenio 2010 CSD2007 - 00006Junta de AndalucĂ­a FQM - 119, Projects P09 - FQM - 5117 and FQM - 2126EU 7th Framework Program, Marie SkƂodowska - Curie actions C OFUND – Agreement nÂș 26722

    The potential science and engineering value of samples delivered to Earth by Mars sample return

    Get PDF
    © The Meteoritical Society, 2019. Executive Summary: Return of samples from the surface of Mars has been a goal of the international Mars science community for many years. Affirmation by NASA and ESA of the importance of Mars exploration led the agencies to establish the international MSR Objectives and Samples Team (iMOST). The purpose of the team is to re-evaluate and update the sample-related science and engineering objectives of a Mars Sample Return (MSR) campaign. The iMOST team has also undertaken to define the measurements and the types of samples that can best address the objectives. Seven objectives have been defined for MSR, traceable through two decades of previously published international priorities. The first two objectives are further divided into sub-objectives. Within the main part of the report, the importance to science and/or engineering of each objective is described, critical measurements that would address the objectives are specified, and the kinds of samples that would be most likely to carry key information are identified. These seven objectives provide a framework for demonstrating how the first set of returned Martian samples would impact future Martian science and exploration. They also have implications for how analogous investigations might be conducted for samples returned by future missions from other solar system bodies, especially those that may harbor biologically relevant or sensitive material, such as Ocean Worlds (Europa, Enceladus, Titan) and others. Summary of Objectives and Sub-Objectives for MSR Identified by iMOST: Objective 1 Interpret the primary geologic processes and history that formed the Martian geologic record, with an emphasis on the role of water. Intent To investigate the geologic environment(s) represented at the Mars 2020 landing site, provide definitive geologic context for collected samples, and detail any characteristics that might relate to past biologic processesThis objective is divided into five sub-objectives that would apply at different landing sites. 1.1 Characterize the essential stratigraphic, sedimentologic, and facies variations of a sequence of Martian sedimentary rocks. Intent To understand the preserved Martian sedimentary record. Samples A suite of sedimentary rocks that span the range of variation. Importance Basic inputs into the history of water, climate change, and the possibility of life 1.2 Understand an ancient Martian hydrothermal system through study of its mineralization products and morphological expression. Intent To evaluate at least one potentially life-bearing “habitable” environment Samples A suite of rocks formed and/or altered by hydrothermal fluids. Importance Identification of a potentially habitable geochemical environment with high preservation potential. 1.3 Understand the rocks and minerals representative of a deep subsurface groundwater environment. Intent To evaluate definitively the role of water in the subsurface. Samples Suites of rocks/veins representing water/rock interaction in the subsurface. Importance May constitute the longest-lived habitable environments and a key to the hydrologic cycle. 1.4 Understand water/rock/atmosphere interactions at the Martian surface and how they have changed with time. Intent To constrain time-variable factors necessary to preserve records of microbial life. Samples Regolith, paleosols, and evaporites. Importance Subaerial near-surface processes could support and preserve microbial life. 1.5 Determine the petrogenesis of Martian igneous rocks in time and space. Intent To provide definitive characterization of igneous rocks on Mars. Samples Diverse suites of ancient igneous rocks. Importance Thermochemical record of the planet and nature of the interior. Objective 2 Assess and interpret the potential biological history of Mars, including assaying returned samples for the evidence of life. Intent To investigate the nature and extent of Martian habitability, the conditions and processes that supported or challenged life, how different environments might have influenced the preservation of biosignatures and created nonbiological “mimics,” and to look for biosignatures of past or present life.This objective has three sub-objectives: 2.1 Assess and characterize carbon, including possible organic and pre-biotic chemistry. Samples All samples collected as part of Objective 1. Importance Any biologic molecular scaffolding on Mars would likely be carbon-based. 2.2 Assay for the presence of biosignatures of past life at sites that hosted habitable environments and could have preserved any biosignatures. Samples All samples collected as part of Objective 1. Importance Provides the means of discovering ancient life. 2.3 Assess the possibility that any life forms detected are alive, or were recently alive. Samples All samples collected as part of Objective 1. Importance Planetary protection, and arguably the most important scientific discovery possible. Objective 3 Quantitatively determine the evolutionary timeline of Mars. Intent To provide a radioisotope-based time scale for major events, including magmatic, tectonic, fluvial, and impact events, and the formation of major sedimentary deposits and geomorphological features. Samples Ancient igneous rocks that bound critical stratigraphic intervals or correlate with crater-dated surfaces. Importance Quantification of Martian geologic history. Objective 4 Constrain the inventory of Martian volatiles as a function of geologic time and determine the ways in which these volatiles have interacted with Mars as a geologic system. Intent To recognize and quantify the major roles that volatiles (in the atmosphere and in the hydrosphere) play in Martian geologic and possibly biologic evolution. Samples Current atmospheric gas, ancient atmospheric gas trapped in older rocks, and minerals that equilibrated with the ancient atmosphere. Importance Key to understanding climate and environmental evolution. Objective 5 Reconstruct the processes that have affected the origin and modification of the interior, including the crust, mantle, core and the evolution of the Martian dynamo. Intent To quantify processes that have shaped the planet's crust and underlying structure, including planetary differentiation, core segregation and state of the magnetic dynamo, and cratering. Samples Igneous, potentially magnetized rocks (both igneous and sedimentary) and impact-generated samples. Importance Elucidate fundamental processes for comparative planetology. Objective 6 Understand and quantify the potential Martian environmental hazards to future human exploration and the terrestrial biosphere. Intent To define and mitigate an array of health risks related to the Martian environment associated with the potential future human exploration of Mars. Samples Fine-grained dust and regolith samples. Importance Key input to planetary protection planning and astronaut health. Objective 7 Evaluate the type and distribution of in-situ resources to support potential future Mars exploration. Intent To quantify the potential for obtaining Martian resources, including use of Martian materials as a source of water for human consumption, fuel production, building fabrication, and agriculture. Samples Regolith. Importance Production of simulants that will facilitate long-term human presence on Mars. Summary of iMOST Findings: Several specific findings were identified during the iMOST study. While they are not explicit recommendations, we suggest that they should serve as guidelines for future decision making regarding planning of potential future MSR missions. The samples to be collected by the Mars 2020 (M-2020) rover will be of sufficient size and quality to address and solve a wide variety of scientific questions. Samples, by definition, are a statistical representation of a larger entity. Our ability to interpret the source geologic units and processes by studying sample sub sets is highly dependent on the quality of the sample context. In the case of the M-2020 samples, the context is expected to be excellent, and at multiple scales. (A) Regional and planetary context will be established by the on-going work of the multi-agency fleet of Mars orbiters. (B) Local context will be established at field area- to outcrop- to hand sample- to hand lens scale using the instruments carried by M-2020. A significant fraction of the value of the MSR sample collection would come from its organization into sample suites, which are small groupings of samples designed to represent key aspects of geologic or geochemical variation. If the Mars 2020 rover acquires a scientifically well-chosen set of samples, with sufficient geological diversity, and if those samples were returned to Earth, then major progress can be expected on all seven of the objectives proposed in this study, regardless of the final choice of landing site. The specifics of which parts of Objective 1 could be achieved would be different at each of the final three candidate landing sites, but some combination of critically important progress could be made at any of them. An aspect of the search for evidence of life is that we do not know in advance how evidence for Martian life would be preserved in the geologic record. In order for the returned samples to be most useful for both understanding geologic processes (Objective 1) and the search for life (Objective 2), the sample collection should contain BOTH typical and unusual samples from the rock units explored. This consideration should be incorporated into sample selection and the design of the suites. The retrieval missions of a MSR campaign should (1) minimize stray magnetic fields to which the samples would be exposed and carry a magnetic witness plate to record exposure, (2) collect and return atmospheric gas sample(s), and (3) collect additional dust and/or regolith sample mass if possible

    Methyl Complexes of the Transition Metals

    Full text link

    Effect of seed treatments and mulch on seedborne bacterial pathogens and yield of tomato (Solanum lycopersicum Mill.) in Tanzania

    No full text
    Journal of Animal & Plant Sciences, 2010. Vol. 8, Issue 3: 1006- 1015. Publication date: 28/10/2010,The study was conducted to assess the presence of seedborne bacteria in four tomato seedlots, the efficacy of seed treatments in reducing bacterial contamination and to determine influence of seed treatment or mulch on crop development and yield. Tomato seedlots were treated using hot water, chlorine, and Ridomil¼ followed by seedborne bacteria pathogen detection. Seedlings from treated and non-treated seedlots were grown in the field in mulched and non-mulched plots. Results showed that all seedlots assessed were contaminated with Clavibacter michiganensis subsp. michiganensis (CMM), Xanthomonas campestris pv. vesicatoria (XCV) and Pseudomonas syringae pv. tomato (PST). ‘Tanya G1’, ‘Tanya G2’ (first and second generation farmer-saved seeds respectively) and commercial ‘Cal J’ seedlots were more highly contaminated with XCV than commercial ‘Tanya’ seedlot. ‘Tanya G2’ had the highest PST contamination but did not differ from other seedlots for CMM. Chlorine and hot water significantly reduced bacterial populations on seeds. Ridomil seed treatment did not affect bacterial contamination compared to the untreated control. Marketable fruit yield differed statistically (P = 0.01) for commercial ‘Tanya’ and ‘Cal J’ seedlots. Commercial ‘Tanya’ and ‘Tanya G1’ had higher yields compared to ‘Cal J’ and ‘Tanya G2’. There was no statistical difference (P = 0.05) among seed sources with respect to incidence of blossom end rot (BER) and sunscald disorders. Chlorine and hot water treatments led to higher number of fruits per plant and increased yield compared to Ridomil treatment and the control. Seed treatment had no significant influence on BER. Plants from hot water treatment produced statistically fewer sunscald fruits compared to control, because of more vigorous growth that provided protective shade. The effect of mulch on the yield components and in reduction of sun-scalded fruits was highly significant (P = 0.0001). Seed treatment and mulch therefore can reduce disease infestation and improve tomato yield

    Effect of seed treatments and mulch on seedborne bacterial pathogens and yield of tomato (Solanum lycopersicum Mill.) in Tanzania

    No full text
    Journal of Animal & Plant Sciences, 2010. Vol. 8, Issue 3: 1006- 1015. Publication date: 28/10/2010,The study was conducted to assess the presence of seedborne bacteria in four tomato seedlots, the efficacy of seed treatments in reducing bacterial contamination and to determine influence of seed treatment or mulch on crop development and yield. Tomato seedlots were treated using hot water, chlorine, and Ridomil¼ followed by seedborne bacteria pathogen detection. Seedlings from treated and non-treated seedlots were grown in the field in mulched and non-mulched plots. Results showed that all seedlots assessed were contaminated with Clavibacter michiganensis subsp. michiganensis (CMM), Xanthomonas campestris pv. vesicatoria (XCV) and Pseudomonas syringae pv. tomato (PST). ‘Tanya G1’, ‘Tanya G2’ (first and second generation farmer-saved seeds respectively) and commercial ‘Cal J’ seedlots were more highly contaminated with XCV than commercial ‘Tanya’ seedlot. ‘Tanya G2’ had the highest PST contamination but did not differ from other seedlots for CMM. Chlorine and hot water significantly reduced bacterial populations on seeds. Ridomil seed treatment did not affect bacterial contamination compared to the untreated control. Marketable fruit yield differed statistically (P = 0.01) for commercial ‘Tanya’ and ‘Cal J’ seedlots. Commercial ‘Tanya’ and ‘Tanya G1’ had higher yields compared to ‘Cal J’ and ‘Tanya G2’. There was no statistical difference (P = 0.05) among seed sources with respect to incidence of blossom end rot (BER) and sunscald disorders. Chlorine and hot water treatments led to higher number of fruits per plant and increased yield compared to Ridomil treatment and the control. Seed treatment had no significant influence on BER. Plants from hot water treatment produced statistically fewer sunscald fruits compared to control, because of more vigorous growth that provided protective shade. The effect of mulch on the yield components and in reduction of sun-scalded fruits was highly significant (P = 0.0001). Seed treatment and mulch therefore can reduce disease infestation and improve tomato yield
    • 

    corecore