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- Packer, M., et al.
(author)
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Clinical effects of endothelin receptor antagonism with bosentan in patients with severe chronic heart failure: results of a pilot study
- 2005
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In: Journal of cardiac failure. - : Elsevier BV. - 1071-9164. ; 11:1, s. 12-20
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Journal article (peer-reviewed)abstract
- BACKGROUND: Endothelin receptor antagonism produces favorable short-term hemodynamic effects in heart failure, but the clinical effects of longer term therapy have not been evaluated. METHODS AND RESULTS: Three hundred and seventy patients with symptoms of heart failure at rest or on minimal exertion and a left ventricular ejection fraction <35% were randomly assigned (double-blind) to placebo (n = 126) or the endothelin receptor antagonist bosentan, titrated slowly (n = 121) or rapidly (n = 123) to a target dose of 500 mg twice daily. Treatment with the study drug was to be maintained for 26 weeks, whereas background medications for heart failure were kept constant. Safety concerns led to early termination of the trial when only 174 patients had had an opportunity to complete 26 weeks of therapy. Bosentan exerted no apparent benefit when all randomized patients were analyzed (P = .709). However, in the first 174 patients who were recruited at least 26 weeks before study termination and who could therefore be followed for the planned duration of the trial, patients in the bosentan groups were more likely to be improved (26% versus 19%) and were less likely to be worse (28% versus 43%), P = .045. When compared with placebo-treated patients, bosentan-treated patients had a increased risk of heart failure during the first month of treatment but a decreased risk of heart failure during the fourth, fifth, and sixth months of therapy. The major noncardiac adverse effects of bosentan included an increase in hepatic transaminases (in 15.6% of patients) and a decrease in hemoglobin (of about 1 g/L). CONCLUSION: Although bosentan exerted no favorable effects in the overall study, our findings suggest that the clinical responses to endothelin antagonism with bosentan in patients with severe chronic heart failure may be dependent on the duration of treatment.
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- Van den Steen, Evi, et al.
(author)
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Brominated flame retardants and organochlorines in the European environment using great tit eggs as a biomonitoring tool
- 2009
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In: Environment International. - : Elsevier BV. - 1873-6750 .- 0160-4120. ; 35:2, s. 310-317
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Journal article (peer-reviewed)abstract
- Large-scale studies are essential to assess the emission patterns and spatial distribution of organohalogenated pollutants (OHPs) in the environment. Bird eggs have several advantages compared to other environmental media which have previously been used to map the distribution of OHPs. In this study, large-scale geographical variation in the occurrence of OHPs, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), was investigated throughout Europe using eggs of a terrestrial residential passerine species, the great tit (Parus major). Great tit eggs from 22 sampling sites, involving urban, rural and remote areas, in 14 European countries were collected and analysed (5-8 eggs per sampling site). The environmentally most important congeners/compounds of the analysed pollutants were detectable in all sampling locations. For PCBs, PBDEs and OCPs, no clear geographical contamination pattern was found. Sum PCB levels ranged from 143 ng/g lipid weight (lw) to 3660 ng/g lw. As expected, PCB concentrations were significantly higher in the sampled urban compared to the remote locations. However, the urban locations did not show significantly higher concentrations compared to the rural locations. Sum PBDEs ranged from 4.0 ng/g lw to 136 ng/g lw. PBDEs were significantly higher in the urbanized sampling locations compared to the other locations. The significant, positive correlation between PCB and PBDE concentrations suggests similar spatial exposure and/or mechanisms of accumulation. Significantly higher levels of OCPs (sum OCPs ranging from 191 ng/g lw to 7830 ng/g lw) were detected in rural sampling locations. Contamination profiles of PCBs, PBDEs and OCPs differed also among the sampling locations, which may be due to local usage and contamination sources. The higher variance among sampling locations for the PCBs and OCPs, suggests that local contamination sources are more important for the PCBs and OCPs compared to the PBDEs. To our knowledge, this is the first study in which bird eggs were used as a monitoring tool for CHPs on such a large geographical scale. (C) 2008 Elsevier Ltd. All rights reserved.
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