815 research outputs found

    Effects of selected food phytochemicals in reducing the toxic actions of TCDD and p,p′-DDT in U937 macrophages

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    To assess the effectiveness of selected food phytochemicals in reducing the toxic effects of the environmental toxicants, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and p,p′-DDT (DDT), we tested the potencies of auraptene, nobiletin, zerumbone, and (±)-13-hydroxy-10-oxo-trans-11-octadecenoic acid (13-HOA) in reversing the inflammatory action of these toxicants in U937 human macrophages. Using quantitative RT–PCR as the initial screening assay, we identified antagonistic actions of zerumbone and auraptene against the action of TCDD and DDT in up-regulating the mRNA expressions of COX-2 and VEGF. The functional significance of the inhibitory action of zerumbone on COX-2 expression was confirmed by demonstrating its suppression of TCDD-induced activation of COX-2 gene expression in mouse MMDD1 cells. We tested auraptene on DDT-induced reactive oxygen species (ROS) formation in U937 macrophages and found that auraptene is a powerful agent antagonizing this action of DDT. To confirm the significance of these actions of zerumbone and auraptene at the cellular level, we assessed their influence on TCDD-induced apoptosis resistance in intact U937 macrophages and found that they are capable of reversing this action of TCDD. In conclusion, zerumbone and auraptene were identified to be the most effective agents in protecting U937 macrophages from developing these cell toxic effects of TCDD and DDT

    Alcohol consumption and body composition in a population-based sample of elderly Australian men

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    Background: Alcohol is calorie dense, and impacts&nbsp;activity, appetite and lipid processing. The aim of this&nbsp;study was to therefore investigate the association between&nbsp;alcohol consumption and components of body composition&nbsp;including bone, fat and lean tissue.Methods: Participants were recruited from a randomly&nbsp;selected, population-based sample of 534 men aged&nbsp;65 years and older enrolled in the Geelong Osteoporosis&nbsp;Study. Alcohol intake was ascertained using a food&nbsp;frequency questionnaire and the sample categorised as nondrinkers or alcohol users who consumed B2, 3&ndash;4 or C5&nbsp;standard drinks on a usual drinking day. Bone mineral&nbsp;density (BMD), lean body mass and body fat mass were&nbsp;measured using dual energy X-ray absorptiometry; overall&nbsp;adiposity (%body fat), central adiposity (%truncal fat) and&nbsp;body mass index (BMI) were calculated. Bone quality was&nbsp;determined by quantitative heel ultrasound (QUS).Results: There were 90 current non-drinkers (16.9 %),&nbsp;266 (49.8 %) consumed 1&ndash;2 drinks/day, 104 (19.5 %) 3&ndash;4&nbsp;drinks/day and 74 (13.8 %) C5 drinks/day. Those consuming C5 drinks/day had greater BMI (?4.8 %), fat mass&nbsp;index (?20.1 %), waist circumference (?5.0 %), %body&nbsp;fat (?15.2 %) and proportion of trunk fat (?5.3 %) and&nbsp;lower lean mass (-5.0 %) than non-drinkers after adjustment for demographic and lifestyle factors. Furthermore,&nbsp;they were more likely to be obese than non-drinkers&nbsp;according to criteria based on BMI (OR = 2.83, 95 %CI&nbsp;1.10&ndash;7.29) or waist circumference (OR = 3.36, 95 %CI&nbsp;1.32&ndash;8.54). There was an inverse relationship between&nbsp;alcohol consumption and QUS parameters and BMD at the&nbsp;mid forearm site; no differences were detected for BMD at&nbsp;other skeletal sites.Conclusion:&nbsp;Higher alcohol intake was associated with&nbsp;greater total and central adiposity and reduced bone&nbsp;quality.<br /

    Cytogerontology since 1881: A reappraisal of August Weismann and a review of modern progress

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    Cytogerontology, the science of cellular ageing, originated in 1881 with the prediction by August Weismann that the somatic cells of higher animals have limited division potential. Weismann's prediction was derived by considering the role of natural selection in regulating the duration of an organism's life. For various reasons, Weismann's ideas on ageing fell into neglect following his death in 1914, and cytogerontology has only reappeared as a major research area following the demonstration by Hayflick and Moorhead in the early 1960s that diploid human fibroblasts are restricted to a finite number of divisions in vitro. In this review we give a detailed account of Weismann's theory, and we reveal that his ideas were both more extensive in their scope and more pertinent to current research than is generally recognised. We also appraise the progress which has been made over the past hundred years in investigating the causes of ageing, with particular emphasis being given to (i) the evolution of ageing, and (ii) ageing at the cellular level. We critically assess the current state of knowledge in these areas and recommend a series of points as primary targets for future research

    modeling the laser ablation process

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    This chapter focuses on the problem of modeling the laser ablation process from a geometrical point of view. The objective is to create a model capable of describing the laser incision depth based on the knowledge of the laser parameters and inputs. The discussion starts with a statement of the problem, which is defined in terms of a supervised regression. Our approach is compared with existing heuristic models for the prediction of ablation depth

    Quantitative X-ray Tomography of the Mouse Cochlea

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    Imaging with hard X-rays allows visualizing cochlear structures while maintaining intrinsic qualities of the tissue, including structure and size. With coherent X-rays, soft tissues, including membranes, can be imaged as well as cells making use of the so-called in-line phase contrast. In the present experiments, partially coherent synchrotron radiation has been used for micro-tomography. Three-dimensional reconstructions of the mouse cochlea have been created using the EM3D software and the volume has been segmented in the Amira Software Suite. The structures that have been reconstructed include scala tympani, scala media, scala vestibuli, Reissner's membrane, basilar membrane, tectorial membrane, organ of Corti, spiral limbus, spiral ganglion and cochlear nerve. Cross-sectional areas of the scalae were measured. The results provide a realistic and quantitative reconstruction of the cochlea

    A bibliometric study of the literature on technological innovation: an analysis of 60 international academic journals

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    This paper aims to contribute to the debate on technological innovation, organization and work. Although technological innovation remained a debated topic in the academic literature during the past years, its implications for organizational processes seem still not sufficiently theorized and empirically investigated. By using two complementary journals’ rankings a search in the ISI Web of Science platform from 1985 through 2013 was performed. To analyze the 998 scientific retrieved contributions a bibliometric analysis has been conducted, adopting also Social Network Analysis tools. Our results reveal a significant growth of the technological innovation literature over the investigated period, the multidisciplinarity of the field and, particularly, the relevance of management and business & economics contributions. Overall, this study offers a broad overview of the literature on technological innovation and emphasizes the opportunity to investigate the role of technological innovation within the organizational life.This paper aims to contribute to the debate on technological innovation, organization and work. Although technological innovation remained a debated topic in the academic literature during the past years, its implications for organizational processes seem still not sufficiently theorized and empirically investigated. By using two complementary journals’ rankings a search in the ISI Web of Science platform from 1985 through 2013 was performed. To analyze the 998 scientific retrieved contributions a bibliometric analysis has been conducted, adopting also Social Network Analysis tools. Our results reveal a significant growth of the technological innovation literature over the investigated period, the multidisciplinarity of the field and, particularly, the relevance of management and business & economics contributions. Overall, this study offers a broad overview of the literature on technological innovation and emphasizes the opportunity to investigate the role of technological innovation within the organizational life.Monograph's chapter

    Esophageal perforation in South of Sweden: Results of surgical treatment in 125 consecutive patients

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    <p>Abstract</p> <p>Background</p> <p>For many years there has been a debate as to which is the method of choice in treating patients with esophageal perforation. The literature consists mainly of small case series. Strategies for aiding patients struck with this disease is changing as new and less traumatic treatment options are developing. We studied a relatively large consecutive material of esophageal perforations in an effort to evaluate prognostic factors, diagnostic efforts and treatment strategy in these patients.</p> <p>Methods</p> <p>125 consecutive patients treated at the University Hospital of Lund from 1970 to 2006 were studied retrospectively. Prognostic factors were evaluated using the Cox proportional hazards model.</p> <p>Results</p> <p>Pre-operative ASA score was the only factor that significantly influenced outcome. Neck incision for cervical perforation (n = 8) and treatment with a covered stent with or without open drainage for a thoracic perforation (n = 6) had the lowest mortality. Esophageal resection (n = 8) had the highest mortality. A CAT scan or an oesophageal X-ray with oral contrast were the most efficient diagnostic tools. The preferred treatment strategy changed over the course of the study period, from a more aggressive surgical approach towards using covered stents to seal the perforation.</p> <p>Conclusion</p> <p>Pre-operative ASA score was the only factor that significantly influenced outcome in this study. Treatment strategies are changing as less traumatic options have become available. Sealing an esophageal perforation with a covered stent, in combination with open or closed drainage when necessary, is a promising treatment strategy.</p

    Functional hemizygosity in the human genome: direct estimate from twelve erythrocyte enzyme loci

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    Cord blood samples from 2020 unrelated newborns were screened for levels of enzyme activity for twelve enzymes. The level of enzymatic activity for 100 determinations were consistent with the existence of an enzyme-deficiency allele. The frequency of deficiency alleles in the Black population (0.0071) was four times higher (after removal of the G6PD * A - variant) than in the Caucasian sample (0.0016). These frequencies are approximately double the frequency of rare electrophoretic mobility variants at similar loci in the same population. Given the number of functionally important loci in the human genome, these enzyme deficiency variants could constitute a significant health burden.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47620/1/439_2004_Article_BF00284477.pd

    Studying the Underlying Event in Drell-Yan and High Transverse Momentum Jet Production at the Tevatron

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    We study the underlying event in proton-antiproton collisions by examining the behavior of charged particles (transverse momentum pT > 0.5 GeV/c, pseudorapidity |\eta| < 1) produced in association with large transverse momentum jets (~2.2 fb-1) or with Drell-Yan lepton-pairs (~2.7 fb-1) in the Z-boson mass region (70 < M(pair) < 110 GeV/c2) as measured by CDF at 1.96 TeV center-of-mass energy. We use the direction of the lepton-pair (in Drell-Yan production) or the leading jet (in high-pT jet production) in each event to define three regions of \eta-\phi space; toward, away, and transverse, where \phi is the azimuthal scattering angle. For Drell-Yan production (excluding the leptons) both the toward and transverse regions are very sensitive to the underlying event. In high-pT jet production the transverse region is very sensitive to the underlying event and is separated into a MAX and MIN transverse region, which helps separate the hard component (initial and final-state radiation) from the beam-beam remnant and multiple parton interaction components of the scattering. The data are corrected to the particle level to remove detector effects and are then compared with several QCD Monte-Carlo models. The goal of this analysis is to provide data that can be used to test and improve the QCD Monte-Carlo models of the underlying event that are used to simulate hadron-hadron collisions.Comment: Submitted to Phys.Rev.
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