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- Håkansson, H., et al.
(författare)
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In vivo and in vitro toxicity of fractionated fish lipids, with particular regard to their content of chlorinated organic compounds
- 1991
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Ingår i: Pharmacology and Toxicology. - : Wiley. - 0901-9928 .- 1600-0773. ; 69:6, s. 459-471
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Tidskriftsartikel (refereegranskat)abstract
- Six different lipid matrices (the intact lipid (IL), four lipid fractions with different polarity, and the free fatty acids (FFAs) obtained by hydrolysis of the triacylglycerol (TAG) containing fraction) were obtained from salmon (Salmo salar) and eel (Anguilla anguilla), each collected at a contaminated and a comparatively uncontaminated catch site along the coast of Scandinavia. The lipid matrices were studied in toxicological test systems representing various biological functions of different organ systems from several species and trophic levels. The results were evaluated with particular respect to the concentrations of extractable organically bound chlorine (EOCl) in the matrices tested. In some test systems, the specimens with a higher EOCl concentration appeared to be more toxic. For example, the TAG containing fraction (F2) from Idefjord eel, having a higher EOCl content than F2 from Oslofjord eel, reduced the number and hatchability of eggs laid by zebrafish. Both IL and F2 of Idefjord eel increased mortality and reduced the oxygen/nitrogen-ratio in blue mussels. Non-polar compounds (F1) from Bothnian Sea salmon induced 7-ethoxyresurofin O-deethylase (EROD) activity in rainbow trout hepatocytes, whereas F1 from Senja salmon did not. F1 from Bothnian Sea salmon also reduced the number of T-cells in foetal mouse thymus anlagen in vitro compared with the cell number in anlagen exposed to F1 from Senja salmon. A positive correlation between EOCl concentration and test response was found for EROD activity in rainbow trout hepatocytes and for ATP-leakage in Erlich ascites tumour cells when testing the phospolipid containing fraction (F4). However, in most test systems the fish oils, irrespective of EOCl content, were of low toxicity, and the observed effects need to be verified in future studies.
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| 3. |
- Antzutkin, Oleg, et al.
(författare)
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Molecular motion of the Morpholin-1-yl radical in CF2 ClCFCl2 as studied by ESR : use of residual anisotrophy of powder spectra to extract dynamics
- 1993
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Ingår i: Chemical Physics. - 0301-0104 .- 1873-4421. ; 169:2, s. 195-205
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Tidskriftsartikel (refereegranskat)abstract
- The dynamics of the deprotonated neutral morpholin-1-yl radical, trapped in a halocarbon matrix, CF2ClCFCl2, has been studied utilizing electron spin resonance (ESR) spectroscopy. The experimental lineshapes of the radical exhibit an alterating line-width effect in the temperature range 105-144 K. The major changes of the ESR lineshape were governed by the averaging of the nitrogen hyperfine anisotropy while no exchange of the isotropic hyperfine coupling constants was observed. Geometrical parameters specifying the restricted anisotropic rotation of the whole radical trapped in the matrix could be extracted. Two methods for simulating anisotropic exchange broadened ESR spectra, the secular and non-perturbative, were utilized to investigate the dynamics of the radical. A surprisingly simple ''three-site'' jump model with a barrier of almost-equal-to 3.6 kcal/mol can be applied in the simulation of the experimental spectra. It has been shown that the secular method cannot reproduce the exchange broadened ESR spectra of systems with large hyperfine anisotropy undergoing large internal reorganisation.
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