2,291 research outputs found

    An alternative synthetic access to cis-4a-Methyloctahydrophenanthrene, a biomarker of Sergipe-Alagoas Basin petroleum in Brazil

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    cis-4a-Methyloctahydrophenanthrene (1) was prepared in 8 steps (23% overall yield) from 2-bromophenyl)acetic acid (3) and cyclohexane-1,3-dione (6). A highly cis-diastereoselective Michael-type Heck coupling served as the key step in the assembly of the tricyclic skeleton. This compound 1 was used as gas chromatography standard which allowed the unequivocal identification of a minor biomarker present in Carmopolis oil from the Sergipe-Alagoas Basin in Brazil.13566466

    Association Between Alcohol Intake and Cardiac Remodeling

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    Background: Alcohol-induced cardiotoxicity is incompletely understood. Specifically, the long-term impact of alcohol use on ventricular remodeling or dysfunction, its modulators, and effect thresholds among young adults remain controversial. Objectives: The authors sought to evaluate a potential relationship between alcohol intake and cardiac remodeling, assessed by echocardiography, over 20 years of follow-up. Methods: Among the CARDIA (Coronary Artery Risk Development in Young Adults) study cohort, the authors studied all subjects without baseline heart disorders who provided adequate information on their drinking habits and underwent echocardiographic evaluation at years 5 and 25 of the study. The echocardiographic outcomes were left ventricular (LV) ejection fraction, indexed LV end-diastolic volume and LV mass, and left atrial diameter. Participants were grouped according to their weighted-average weekly drinking habits. An additional analysis used the estimated cumulative alcohol consumption. Regression models and multivariable fractional polynomials were used to evaluate the association between alcohol consumption and the outcomes. Results: Among the 2,368 participants, alcohol consumption was an independent predictor of higher indexed LV mass (p = 0.014) and indexed LV end-diastolic volume (p = 0.037), regardless of sex. No significant relationship between alcohol intake and LV ejection fraction was found. Drinking predominantly wine was associated with less cardiac remodeling and there was a nonsignificant trend for a harmful effect of binge drinking. Conclusions: After 20 years of follow-up, alcohol intake was associated with adverse cardiac remodeling, although it was not related with LV systolic dysfunction in this initially healthy young cohort. Our results also suggest that drinking predominantly wine associates with less deleterious findings in cardiac structure.info:eu-repo/semantics/publishedVersio

    Strategies to mitigate the emission of methane in pastures: Enteric methane: A review

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    The global population reached 7.9 billion in 2021, which represents a 160% increase in the number of people to be fed since 1960. Agricultural systems must sustainably meet food demand for this growing population while minimizing or mitigating potential environmental impacts, which are of growing concern to both consumers and the scientific community. High protein animal products (meat and milk) play a crucial part in human nutrition and pastures represent ~20% of the planet’s surface. Pastoral areas have a great influence on both ecological balance and human subsistence. Ruminant livestock production systems are hotly debated because of the emission of methane, which is produced during enteric fermentation of ingested food within the rumen. Methanogenesis is a naturally occurring process in the digestive system of ruminant animals and ingesting a high-quality diet has been shown to reduce methane production. An additional function of pastoral grasslands is the capacity of the soils to operate as carbon sinks. Well managed pastures absorb carbon from the atmosphere where it can add to soil organic matter directly, through residue decomposition or excrement returns. However, in Brazil and globally, the efficiency of animal productivity tends to be lower in extensively grazed farming systems. Changes to pasture and grazing management in combination with the adoption of technology is necessary to improve the quality of pastures, increase animal productivity, and consequently reduce methane emissions from ruminant livestock. This review will discuss how to improve the conversion efficiency using pasture management to reduce or mitigate enteric methane production

    Anterior ischemic optic neuropathy and hematologic malignancy: a systematic review of case reports and case series

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    OBJECTIVE: Demographic and clinical characteristics associated with nonarteritic anterior ischemic optic neuropathy (NAION) are well described. Patients with hematologic neoplasms may share some of these characteristics, and it may be useful clinically to better understand this set of patients. Our objective is to review systematically the characteristics of patients with both hematologic malignancies and NAION. DESIGN: Systematic review. PARTICIPANTS: Patients with NAION diagnosis related in time to a hematologic neoplasm. METHODS: Data sources for the study included MEDLINE, Web of Science, LILACS, SciELO, and OpenGrey. The study eligibility criteria included case reports and case series. RESULTS: We found 261 records, with 15 studies included plus our case report. A total of 19 patients (8 female) with mean age of 54.6 years (range, 12-87) were analyzed: 37% (7) non-Hodgkin lymphoma; 26% (5) myeloproliferative neoplasms; 21% (4) myelodysplasia; 16% (3) leukemias. The limitations included verification bias, inability to test statistical association between NAION and hematologic neoplasms, the small number of cases, and confounding factors related to medical history and specific interventions in each case limited the robustness of our conclusions. CONCLUSIONS: Our results identified the characteristics of patients with NAION and hematologic neoplasms related in time. Additional observational studies may enlighten the importance of looking for evidence of an occult neoplastic disorder in patients presenting with NAION. A prompt diagnosis would be of invaluable significance for the best management, in terms of follow-up and therapeutics

    Compartmentalized cytotoxic immune response leads to distinct pathogenic roles of natural killer and senescent CD8⁺ T cells in human cutaneous leishmaniasis

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    Cytotoxic activity mediated by CD8+ T cells is the main signature of the immunopathogenesis of cutaneous leishmaniasis (CL). Here, we performed a broad evaluation of natural killer (NK) cell phenotypic and functional features during cutaneous leishmaniasis. We demonstrate for the first time that CL patients present the accumulation of circulating NK cells with multiple features of replicative senescence including low proliferative capacity and shorter telomeres, elevated expression of CD57, KLRG1 but diminished CD27 stimulatory receptor expression. Moreover, they exhibited higher cytotoxic and inflammatory potential than age‐matched controls. The accumulation of circulating senescent NK cells (CD56dim CD57bright) correlated positively with skin lesion size in the same patients, suggesting that they, like circulating senescent CD8+ T cells, may contribute to the immunopathology of CL. However, this senescent population had lower cutaneous lymphocyte antigen expression and so had diminished skin‐homing potential compared with total or senescent CD8+ T cells. This was confirmed in CL skin lesions where we found a predominance of CD8+ T cells (both senescent and non‐senescent) that correlated with the severity of the disease. Although there was also a correlation between the proportions of senescent NK cells (CD56+ CD57+) in the skin and lesion size, this was less evident. Collectively our results demonstrate first‐hand that senescent cytotoxic cells may mediate skin pathology during human cutaneous leishmaniasis. However, as senescent cytotoxic CD8+ T cells predominate in the skin lesions, they may have a greater role than NK cells in mediating the non‐specific skin damage in CL

    A novel RFC1 repeat motif (ACAGG) in two Asia-Pacific CANVAS families

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    Cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS) is a progressive late-onset, neurological disease. Recently, a pentanucleotide expansion in intron 2 of RFC1 was identified as the genetic cause of CANVAS. We screened an Asian-Pacific cohort for CANVAS and identified a novel RFC1 repeat expansion motif, (ACAGG)exp, in three affected individuals. This motif was associated with additional clinical features including fasciculations and elevated serum creatine kinase. These features have not previously been described in individuals with genetically-confirmed CANVAS. Haplotype analysis showed our patients shared the same core haplotype as previously published, supporting the possibility of a single origin of the RFC1 disease allele. We analysed data from >26 000 genetically diverse individuals in gnomAD to show enrichment of (ACAGG) in non-European populations

    Roles for Treg expansion and HMGB1 signaling through the TLR1-2-6 axis in determining the magnitude of the antigen-specific immune response to MVA85A

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    © 2013 Matsumiya et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedA better understanding of the relationships between vaccine, immunogenicity and protection from disease would greatly facilitate vaccine development. Modified vaccinia virus Ankara expressing antigen 85A (MVA85A) is a novel tuberculosis vaccine candidate designed to enhance responses induced by BCG. Antigen-specific interferon-γ (IFN-γ) production is greatly enhanced by MVA85A, however the variability between healthy individuals is extensive. In this study we have sought to characterize the early changes in gene expression in humans following vaccination with MVA85A and relate these to long-term immunogenicity. Two days post-vaccination, MVA85A induces a strong interferon and inflammatory response. Separating volunteers into high and low responders on the basis of T cell responses to 85A peptides measured during the trial, an expansion of circulating CD4+ CD25+ Foxp3+ cells is seen in low but not high responders. Additionally, high levels of Toll-like Receptor (TLR) 1 on day of vaccination are associated with an increased response to antigen 85A. In a classification model, combined expression levels of TLR1, TICAM2 and CD14 on day of vaccination and CTLA4 and IL2Rα two days post-vaccination can classify high and low responders with over 80% accuracy. Furthermore, administering MVA85A in mice with anti-TLR2 antibodies may abrogate high responses, and neutralising antibodies to TLRs 1, 2 or 6 or HMGB1 decrease CXCL2 production during in vitro stimulation with MVA85A. HMGB1 is released into the supernatant following atimulation with MVA85A and we propose this signal may be the trigger activating the TLR pathway. This study suggests an important role for an endogenous ligand in innate sensing of MVA and demonstrates the importance of pattern recognition receptors and regulatory T cell responses in determining the magnitude of the antigen specific immune response to vaccination with MVA85A in humans.This work was funded by the Wellcome Trust. MM has a Wellcome Trust PhD studentship and HM is a Wellcome Trust Senior Fello
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