57 research outputs found

    Acute effects of ferumoxytol on regulation of renal hemodynamics and oxygenation

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    The superparamagnetic iron oxide nanoparticle ferumoxytol is increasingly used as intravascular contrast agent in magnetic resonance imaging (MRI). This study details the impact of ferumoxytol on regulation of renal hemodynamics and oxygenation. In 10 anesthetized rats, a single intravenous injection of isotonic saline (used as volume control) was followed by three consecutive injections of ferumoxytol to achieve cumulative doses of 6, 10, and 41 mg Fe/kg body mass. Arterial blood pressure, renal blood flow, renal cortical and medullary perfusion and oxygen tension were continuously measured. Regulation of renal hemodynamics and oxygenation was characterized by dedicated interventions: brief periods of suprarenal aortic occlusion, hypoxia, and hyperoxia. None of the three doses of ferumoxytol resulted in significant changes in any of the measured parameters as compared to saline. Ferumoxytol did not significantly alter regulation of renal hemodynamics and oxygenation as studied by aortic occlusion and hypoxia. The only significant effect of ferumoxytol at the highest dose was a blunting of the hyperoxia-induced increase in arterial pressure. Taken together, ferumoxytol has only marginal effects on the regulation of renal hemodynamics and oxygenation. This makes ferumoxytol a prime candidate as contrast agent for renal MRI including the assessment of renal blood volume fraction

    Black carbon as an additional indicator of the adverse health effects of airborne particles compared with PM10 and PM2.5.

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    Current air quality standards for particulate matter (PM) use the PM mass concentration [PM with aerodynamic diameters ≤ 10 μm (PM(10)) or ≤ 2.5 μm (PM(2.5))] as a metric. It has been suggested that particles from combustion sources are more relevant to human health than are particles from other sources, but the impact of policies directed at reducing PM from combustion processes is usually relatively small when effects are estimated for a reduction in the total mass concentration

    Управління загрозами фінансовій безпеці підприємства

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    Розроблено блок-схему алгоритму управління загрозами фінансовій безпеці підприємства; виділено основні етапи здійснення цього процесу: оцінювання, аналіз та управління. Визначено сутність, зміст, переваги та недоліки застосування методів оцінювання загроз фінансовій безпеці в системі фінансового менеджменту підприємства. Ключові слова: підприємство, фінансова безпека, загрози, оцінювання, аналіз, управління.Составлена блок-схема алгоритма управления угрозами финансовой безопасности предприятия. Выделены основные этапы осуществления данного процесса: оценивание, анализ и управление. Определены сущность, содержание, преимущества и недостатки методов оценивания угроз финансовой безопасности в системе финансового менеджмента предприятия. Ключевые слова: предприятие, финансовая безопасность, угрозы, оценивание, анализ, управление.Enterprise financial security threats management main terms essence and contents were defined on the basis of financial and economic literature analysis and generalization: enterprise financial security threats management is a multistage process, which includes evaluation, management and analysis of enterprise financial security threats management; evaluation of enterprise financial security threats is a process of identification of threats influence on enterprise financial security; analysis of enterprise financial security threats is a process of threats identification, which influence on enterprise financial security. It is established that the majority of modern domestic and foreign scientists consider two groups of enterprise financial security threats estimation: qualitative or subjective (expert, probabilistic (concerning loss, favorable possibilities), consequences analysis) and quantitative or objective (statistical, analytical, rating, expense expediency, analogues, decision tree, normative). Comparative analysis of qualitative and quantitative enterprise financial security threats estimation enables to detect that use either of them has its own advantages and disadvantages. Some methods require using the considerable mass data and at the same time leave out of the account the time factor; others are insufficiently developed for using in the domestic economic conditions. Therefore the choice of the method is made only owing to the purpose of the enterprise financial security threats estimation. It is proved that the methods of the enterprise financial security threats management could be divided into three groups: reduction, maintenance and transmission. Reduction of enterprise financial security threats level provides preventive management and logistical measures implementation as to unfavorable events in financial and economic activities prevention or negative consequences liquidation. As measures, implemented for enterprise financial security threats level maintaining, could be referred the following: getting loans on compensation for losses, which enterprise got as a result of unforeseen, unfavorable events in its financial and economic activities, resumption of output production (goods, works, services) with the help of finance and credit establishments activities, government grants etc. Keywords: enterprise, financial security, threats, evaluation, analysis, management

    Contrasts in Oxidative Potential and Other Particulate Matter Characteristics Collected Near Major Streets and Background Locations

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    Background: Measuring the oxidative potential of airborne particulate matter (PM) may provide a more health-based exposure measure by integrating various biologically relevant properties of PM into a single predictor of biological activity

    In vitro toxicity of particulate matter (PM) collected at different sites in the Netherlands is associated with PM composition, size fraction and oxidative potential - the RAPTES project

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    <p>Abstract</p> <p>Background</p> <p>Ambient particulate matter (PM) exposure is associated with respiratory and cardiovascular morbidity and mortality. To what extent such effects are different for PM obtained from different sources or locations is still unclear. This study investigated the <it>in vitro </it>toxicity of ambient PM collected at different sites in the Netherlands in relation to PM composition and oxidative potential.</p> <p>Method</p> <p>PM was sampled at eight sites: three traffic sites, an underground train station, as well as a harbor, farm, steelworks, and urban background location. Coarse (2.5-10 μm), fine (< 2.5 μm) and quasi ultrafine PM (qUF; < 0.18 μm) were sampled at each site. Murine macrophages (RAW 264.7 cells) were exposed to increasing concentrations of PM from these sites (6.25-12.5-25-50-100 μg/ml; corresponding to 3.68-58.8 μg/cm<sup>2</sup>). Following overnight incubation, MTT-reduction activity (a measure of metabolic activity) and the release of pro-inflammatory markers (Tumor Necrosis Factor-alpha, TNF-α; Interleukin-6, IL-6; Macrophage Inflammatory Protein-2, MIP-2) were measured. The oxidative potential and the endotoxin content of each PM sample were determined in a DTT- and LAL-assay respectively. Multiple linear regression was used to assess the relationship between the cellular responses and PM characteristics: concentration, site, size fraction, oxidative potential and endotoxin content.</p> <p>Results</p> <p>Most PM samples induced a concentration-dependent decrease in MTT-reduction activity and an increase in pro-inflammatory markers with the exception of the urban background and stop & go traffic samples. Fine and qUF samples of traffic locations, characterized by a high concentration of elemental and organic carbon, induced the highest pro-inflammatory activity. The pro-inflammatory response to coarse samples was associated with the endotoxin level, which was found to increase dramatically during a three-day sample concentration procedure in the laboratory. The underground samples, characterized by a high content of transition metals, showed the largest decrease in MTT-reduction activity. PM size fraction was not related to MTT-reduction activity, whereas there was a statistically significant difference in pro-inflammatory activity between Fine and qUF PM. Furthermore, there was a statistically significant negative association between PM oxidative potential and MTT-reduction activity.</p> <p>Conclusion</p> <p>The response of RAW264.7 cells to ambient PM was markedly different using samples collected at various sites in the Netherlands that differed in their local PM emission sources. Our results are in support of other investigations showing that the chemical composition as well as oxidative potential are determinants of PM induced toxicity <it>in vitro</it>.</p

    Determinants of the Proinflammatory Action of Ambient Particulate Matter in Immortalized Murine Macrophages

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    Background: Proximity to traffic-related pollution has been associated with poor respiratory health in adults and children. Objectives: We wished to test the hypothesis that particulate matter (PM) from high-traffic sites would display an enhanced capacity to elicit inflammation. Methods: We examined the inflammatory potential of coarse [2.5–10 μm in aerodynamic diameter (PM2.5–10)] and fine [0.1–2.5 μm in aerodynamic diameter (PM0.1–2.5)] PM collected from nine sites throughout Europe with contrasting traffic contributions. We incubated murine monocytic-macrophagic RAW264.7 cells with PM samples from these sites (20 or 60 μg/cm2) and quantified their capacity to stimulate the release of arachidonic acid (AA) or the production of interleukin-6 and tumor necrosis factor-α (TNFα) as measures of their inflammatory potential. Responses were then related to PM composition: metals, hydrocarbons, anions/cations, and endotoxin content. Results: Inflammatory responses to ambient PM varied markedly on an equal mass basis, with PM2.5–10 displaying the largest signals and contrasts among sites. Notably, we found no evidence of enhanced inflammatory potential at high-traffic sites and observed some of the largest responses at sites distant from traffic. Correlation analyses indicated that much of the sample-to-sample contrast in the proinflammatory response was related to the content of endotoxin and transition metals (especially iron and copper) in PM2.5–10. Use of the metal chelator diethylene triamine pentaacetic acid inhibited AA release, whereas recombinant endotoxin-neutralizing protein partially inhibited TNFα production, demonstrating that different PM components triggered inflammatory responses through separate pathways. Conclusions: We found no evidence that PM collected from sites in close proximity to traffic sources displayed enhanced proinflammatory activity in RAW264.7 cells. Key words: copper, endotoxin, inflammation, iron, macrophages, metals, particulate matter, polyaromatic hydrocarbons. Environ Health Perspect 118:1728–1734 (2010). doi:10.1289/ehp.1002105 [Online 27 July 2010

    EuReCa ONE—27 Nations, ONE Europe, ONE Registry A prospective one month analysis of out-of-hospital cardiac arrest outcomes in 27 countries in Europe

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    AbstractIntroductionThe aim of the EuReCa ONE study was to determine the incidence, process, and outcome for out of hospital cardiac arrest (OHCA) throughout Europe.MethodsThis was an international, prospective, multi-centre one-month study. Patients who suffered an OHCA during October 2014 who were attended and/or treated by an Emergency Medical Service (EMS) were eligible for inclusion in the study. Data were extracted from national, regional or local registries.ResultsData on 10,682 confirmed OHCAs from 248 regions in 27 countries, covering an estimated population of 174 million. In 7146 (66%) cases, CPR was started by a bystander or by the EMS. The incidence of CPR attempts ranged from 19.0 to 104.0 per 100,000 population per year. 1735 had ROSC on arrival at hospital (25.2%), Overall, 662/6414 (10.3%) in all cases with CPR attempted survived for at least 30 days or to hospital discharge.ConclusionThe results of EuReCa ONE highlight that OHCA is still a major public health problem accounting for a substantial number of deaths in Europe.EuReCa ONE very clearly demonstrates marked differences in the processes for data collection and reported outcomes following OHCA all over Europe. Using these data and analyses, different countries, regions, systems, and concepts can benchmark themselves and may learn from each other to further improve survival following one of our major health care events

    Myocardial T2* mapping at ultrahigh magnetic fields: in vivo myocardial tissue characteri-zation and assessment of cardiac physiology with magnetic resonance imaging

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    Mapping the effective transverse relaxation time T2* represents an emerging MRI tool for non-invasive myocardial tissue characterization and holds the promise to provide means for assessing myocardial (patho)physiology in vivo. This work takes advantage of the linear increase of susceptibility effects with magnetic field strength which renders it appealing to perform T2* mapping at ultrahigh magnetic fields and enables temporally resolved T2* mapping. Recognizing this potential this study examines the applicability of myocardial CINE T2* mapping in healthy volunteers and hypertrophic cardiomyopathy (HCM) patients at 7.0 Tesla and investigates its capability to distinguish between healthy myocardium and myocardium affected by HCM
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