12 research outputs found

    Air Pollution–Related Prothrombotic Changes in Persons with Diabetes

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    Background: Population studies suggest that persons with diabetes are more sensitive to the effects of particulate matter (PM) air pollution. However, the biological mechanisms of a possible prothrombotic effect underlying this enhanced susceptibility remain largely unknown.Objective: We hypothesized that exposure to PM causes prothrombotic changes in persons with diabetes, possibly via systemic inflammation.Methods: Our study included 137 nonsmoking adults with diabetes who were outpatients at the University Hospital Leuven. Recent exposure (2 hr before examination) to ambient PM was measured at the entrance of the hospital. Individual chronic exposure to PM was assessed by measuring the area occupied by carbon in airway macrophages obtained by sputum induction. Platelet function was measured ex vivo with the PFA-100 platelet function analyzer, which simulates a damaged blood vessel; we analyzed the function of platelets in primary hemostasis under high shear conditions. Total and differential blood leukocytes were counted.Results: Independent of antiplatelet medication, an interquartile range (IQR) increase of 39.2 microg/m3 in PM10 (PM with aerodynamic diameter </= 10 microm) concentration measured 2 hr before the clinical examination (recent exposure) was associated with a decrease of 21.1 sec [95% confidence interval (CI), 35.3 to 6.8] in the PFA-100 closure time (i.e., increased platelet activation) and an increase in blood leukocytes of 512 per microliter of blood (95% CI, 45.2979). Each area increase of 0.25 microm2 (IQR) in carbon load of airway macrophages (chronic exposure) was associated with an increase of 687 leukocytes per microliter of blood (95% CI, 2241,150).Conclusions: A relevant increase in recent PM exposure was associated with a change in platelet function toward a greater prothrombotic tendency. The magnitude of the change was about two-thirds (in the opposite direction) of the average effect of antiplatelet medication. Diabetic patients showed evidence of proinflammatory response to both recent and chronic exposure to PM air pollution. Editor's SummaryDiabetics are at increased risk of cardiovascular diseases, and the association between particulate matter (PM) air pollution and cardiovascular outcomes may be stronger among diabetics than among nondiabetics. Jacobs et al. (p. 191) hypothesized that susceptibility to adverse cardiovascular outcomes among diabetics might be related to prothrombotic and inflammatory effects of PM. The authors estimated associations between PM exposures and measures of platelet function (estimated using the PFA-100 platelet function analyzer) and systemic inflammation (total and differential white blood cell counts) among 63 well-controlled diabetics (29 type I, 34 type II). Exposures included modeled estimates of average ambient residential PM10 (PM with aerodynamic diameter </= 10 microm), recent PM10 and PM2.5 (aerodynamic diameter </= 2.5 microm) exposures (at the study hospital), and a proxy measure of chronic carbon load (median area occupied by carbon in 50 airway macrophages from an induced sputum sample.) The authors report that recent PM10 exposure was associated with increased platelet activation, both before and after adjustment for type of diabetes and use of medications that inhibit platelet aggregation, and that carbon load was positively associated with platelet and white blood cell counts. The authors conclude that findings are consistent with proinflammatory responses to PM air pollution among diabetics.status: publishe

    Traffic Air Pollution and Oxidized LDL

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    BACKGROUND: Epidemiologic studies indirectly suggest that air pollution accelerates atherosclerosis. We hypothesized that individual exposure to particulate matter (PM) derived from fossil fuel would correlate with plasma concentrations of oxidized low-density lipoprotein (LDL), taken as a marker of atherosclerosis. We tested this hypothesis in patients with diabetes, who are at high risk for atherosclerosis. METHODOLOGY/PRINCIPAL FINDINGS: In a cross-sectional study of non-smoking adult outpatients with diabetes we assessed individual chronic exposure to PM by measuring the area occupied by carbon in airway macrophages, collected by sputum induction and by determining the distance from the patient's residence to a major road, through geocoding. These exposure indices were regressed against plasma concentrations of oxidized LDL, von Willebrand factor and plasminogen activator inhibitor 1 (PAI-1). We could assess the carbon load of airway macrophages in 79 subjects (58 percent). Each doubling in the distance of residence from major roads was associated with a 0.027 µm(2) decrease (95% confidence interval (CI): -0.048 to -0.0051) in the carbon load of airway macrophages. Independently from other covariates, we found that each increase of 0.25 µm(2) [interquartile range (IQR)] in carbon load was associated with an increase of 7.3 U/L (95% CI: 1.3 to 13.3) in plasma oxidized LDL. Each doubling in distance of residence from major roads was associated with a decrease of -2.9 U/L (95% CI: -5.2 to -0.72) in oxidized LDL. Neither the carbon load of macrophages nor the distance from residence to major roads, were associated with plasma von Willebrand factor or PAI-1. CONCLUSIONS: The observed positive association, in a susceptible group of the general population, between plasma oxidized LDL levels and either the carbon load of airway macrophages or the proximity of the subject's residence to busy roads suggests a proatherogenic effect of traffic air pollution

    Reference values of trace elements in blood and/or plasma in adults living in Belgium

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    Objectives: Trace elements (TEs) from natural and anthropogenic sources are ubiquitous. Essential or not, their relevance for human health and disease is constantly expanding. Biological monitoring is a widely integrated tool in risk assessment both in occupational and environmental settings. However, the determination of appropriate and accurate reference values in the (specific) population is a prerequisite for a correct interpretation of biomonitoring data. This study aimed at determining the reference distribution for TEs (Al, As, Sb, Be, Bi, Cd, Co, Cu, Mn, Hg, Mo, Ni, Pb, Se, Tl, Sn, V, Zn) in the blood and/or plasma of the adult population in Belgium. Methods: Blood and plasma samples were analyzed for 178 males and 202 females, recruited according to an a priori selection procedure, by inductively coupled plasma mass spectrometry (ICP-MS). Results: Reference values were established with high confidence for AsT, Cd, Cu, HgT, Mn, Mo, Pb, Sn, Se, Tl and Zn. Compared to previously published data in the Belgian population, a decreasing time trend is observed for Zn, Cd and Pb. Globally, the results also indicate that the current exposure levels to TEs in the Belgian population are similar to those from other recent national surveys. Conclusions: These reference values and limits obtained through validated analytical and statistical methods will be useful for future occupational and/or environmental surveys. They will contribute to decision-making concerning both public health policies but also exposure assessments on an individual scale

    Verschil moet er zijn: betere segmentatie door het combineren van databronnen

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    In dit artikel bespreken we hoe marketeers door databronnen te combineren tot rijkere inzichten in complexe omgevingen kunnen komen. En hoe zij vanuit deze rijkere inzichten tot een betere segmentatiemethode kunnen komen. Ter illustratie nemen we de pensioencontext als voorbeeld. We laten zien dat het gebruik van socio-demografische factoren alleen niet genoeg is voor een betekenisvolle segmentatie. We ontwikkelen het Retirement Belief Model om te identificeren welke factoren beïnvloeden of deelnemers zich informeren over hun pensioen. Om diverse factoren (sociodemografische, overtuigingen, emoties, financiële voorkeuren en kennis) in één model te kunnen testen, combineren we data uit verschillende bronnen: administratieve data, data vanuit een enquête en data vanuit experimenten. Alleen op deze manier komen we tot een volledig beeld van welke factoren relevant zijn voor informatie- en activatiegedrag van pensioendeelnemers. We gebruiken het Retirement Belief Model vervolgens voor de segmentatie van deelnemers, een grondslag voor effectieve gepersonaliseerde pensioencommunicatie

    Reference values and upper reference limits for 26 trace elements in the urine of adults living in Belgium.

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    Abstract Background: Trace elements (TEs) are ubiquitous and their potential interest for human health has been constantly expanding. Biological monitoring is generally considered to be a useful tool to assess human exposure to chemical agents in risk assessment both at occupational and environmental levels. However, the knowledge of accurate reference values, which may vary across countries or regions, is a prerequisite for correct interpretation of biomonitoring data. This study aimed at determining the reference distribution and the upper reference limit for 26 TEs (Al, As, Sb, Ba, Be, Bi, Cd, Cr, Co, Cu, In, Li, Mn, Hg, Mo, Ni, Pd, Pt, Pb, Se, Te, Tl, Sn, U, V, Zn) in the urine of the general adult population residing in Belgium. Methods: In total, 1022 adults not occupationally or extra-occupationally (mainly via hobbies, drugs) exposed to these TEs were recruited by occupational physicians and toxicologists according to an a priori selection procedure. Non-fasting spot urine samples were analyzed for 460 males and 541 females by inductively coupled plasma mass spectrometry (ICP-MS). Careful control was applied during collection, handling and analyses of the samples to avoid any contamination. Results: Globally, the results indicate that the exposure levels of the Belgian population to these TEs are low and grossly similar to those recently published by other national surveys. Conclusions: These new reference values and upper reference limits will be useful for future occupational and/or environmental surveys

    Traffic related exposure variables and oxidized-LDL.

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    <p>An airway macrophage containing carbon particles (A). We determined the surface of the macrophage occupied by carbon (in µm<sup>2</sup>), in 50 macrophages per person. The carbon load is given as the median carbon load of 50 airway macrophages. Pearson correlation between carbon load of airway macrophages and distance from the residence to a major road (B). (Data leading to panel b have been previously published <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0016200#pone.0016200-Jacobs1" target="_blank">[16]</a>). The shortest distance to a major road is 10 meters, by definition. Pearson correlation between plasma concentrations of oxidized LDL and carbon load of airway macrophages (C) and between plasma concentrations of oxidized LDL and distance from the residence to a major road (D).</p
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