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The aim of this study is to assess the suitability of use of a selected battery of biological tests to evaluate ecotoxicity of mine tailings before biological recultivation of mining dumps. Samples of mine tailings were collected at mining dump Jeremenko in Kunčice nad Ostravicí. For determination of acute toxicity, contact test using earthworms Eisenia foetida, germination and growth inhibition test using seeds of Sinapis alba, luminescence test using bacteria Vibrio fischeri and enzyme acetylcholinesterase inhibition assessment were used. Results showed clearly that indicator organisms reacted sensitively to the presence of toxicological substances found in mine tailings samples. These samples were collected at five locations at mining dump of Jeremenko mine. In three of these locations, a toxicological effect could be observed in all indicator organisms. This study proved the suitability of application of ecotoxicological evaluation for determination of possible use of biological recultivation at mining dumps.
Celem przeprowadzonych badań jest ocena przydatności zastosowania wybranej baterii testów biologicznych do oceny ekotoksyczności odpadów kopalnianych przed biologiczną rekultywacją hałd górniczych. Próbki odpadów kopalnianych pobrano na składowisku Jeremenko w Kunčicach nad Ostrawicą. W celu określenia ostrej toksyczności zastosowano test kontaktowy z wykorzystaniem dżdżownic Eisenia foetida, test zahamowania kiełkowania i wzrostu z wykorzystaniem nasion Sinapis alba, test luminescencji z wykorzystaniem bakterii Vibrio fischeri oraz ocenę hamowania enzymu acetylocholinesterazy. Wyniki wykazały wyraźnie, że organizmy wskaźnikowe reagowały wrażliwie na obecność substancji toksykologicznych w próbkach odpadów kopalnianych. Próbki te pobrano w pięciu lokalizacjach na hałdzie kopalni Jeremenko. W trzech z tych miejsc można zaobserwować efekt toksykologiczny we wszystkich organizmach wskaźnikowych. Badanie to potwierdziło przydatność zastosowania oceny ekotoksykologicznej do określenia możliwego zastosowania rekultywacji biologicznej na hałdach górniczych.
An active biomonitoring study was carried out on the Algerian west coast using wild reference mussels (Mytilus galloprovincialis) sampled from the Kristel (K) site and transplanted in net cages during one month (between May and June 2007) to Oran Harbour (OH) and Mostaganem Harbour (MH), areas characterised by high levels of urban and industrial pollution. The biological response of the mussels was evaluated by their condition index and the use of a general stress biomarker (evaluation of lysosomal membrane stability: the neutral red retention time (NRRT) method), a genotoxic effects biomarker (determination of micronuclei (MN) frequency) and a neurotoxic effects biomarker (determination of the acetylcholinesterase (AChE) concentration). Compared to the K reference specimens, OH and MH caged mussels presented a significant decrease of NRRT in lysosomal haemocytes (56.45 š 26.48 min and 67.25 š 22.77 min, respectively) (78 š 16.97 min for K mussels), an MN frequency respectively 7.3 and 9 times higher in the haemocytes and the gill cells of the OH caged mussels, and 7.2 and 6.4 times higher in the two tissues of the MH caged mussels. Significant inhibition of AChE activity was noted in the gills (16.93 š 3.1 nmol min-1 mg prot-1) and the digestive gland (7.69 š 1.79 nmol min-1 mg prot-1) of the OH mussels, but only in the gills (23.21 š 5.94 nmol min-1 mg prot-1) of the MH mussels, compared to the organs of the K control specimens (35.9 š 6.4 nmol min-1 mg prot-1 in the gills and 11.17 š 0.49 nmol min-1 mg prot-1 in the digestive gland). This study reflects the interest in such in situ biomonitoring assays and the utility of these biomarkers for assessing the effects of pollution in the Algerian coastal marine environment.
The Algerian west coast is the prime recipient of several forms of pollution; hence, the necessity for an impact assessment of this coastal pollution using a suite of recommended marine biomarkers, including lysosomal membrane stability in living cells by the Neutral Red Retention Time (NRRT) method, the evaluation of micronucleus (MN) frequency, and the determination of acetylcholinesterase (AChE) activity in mussels Mytilus galloprovincialis, sampled from the large, polluted Oran Harbour (OH) and the Maârouf (Mrf) marine mussel farm between July 2005 and April 2006. The difference in the variations of the annual physical parameters between OH and Mrf corresponds to the influence of the domestic and industrial sewage discharged by the city of Oran. The biological data of the mussels (condition index, protein content) recorded at both sites were related to their natural reproductive cycle. This indicated that intrinsic variation between the sites due to different mussel development phases was minimal. The variation in the AChE activity of some organs of OH and Mrf mussels, with minimal inhibition in July and a higher NRRT recorded in the granular haemocytes in the Mrf than in the OH mussels during the autumn and spring, depends on the quality of the biotope and on generic stress factors. Moreover, the variation in MN frequency, in general reflecting a non-significant seasonal and spatial genotoxic effect of the contamination at the two sampling sites, requires further investigations regarding biotic and abiotic variations.
AChE activities were measured in blue mussels gills and flounder muscles samples collected off Poland - the Gulf of Gdańsk (4 sampling stations) and off Lithuania - the Klajpe.da area (3 sampling stations), in 2001 (June and October) and 2002 (April and October). The AChE activities [nmol min-1 mg protein-1] were in the range: 15-38 (in blue mussels) and 94-315 (in flounder), and agreed well with those reported for flounder in other coastal Baltic areas, and other European seas. Sources of contaminants in the study area are rather localized in the Gulf of Gdansk, (mouth of the Vistula due to runoff, ports, sewage discharges), while an accidental oil spill occurred off Lithuania, in the course of the study (November 2001). Geographical and temporal AChE levels changes followed the contamination pattern. AChE activities and gradients in the study area are well documented and confirmed in this study. The study confirms the potential use of AChE as biomarker of organic pollution.
Secondary isotope effects for carbonyl addition reactions of methyl thioacetate, acetone and acetaldehyde have been calculated by ab initio quantum mechanical methods in an effort to interpret measured beta-deuterium isotope effects on acetylcholinesterase- catalyzed hydrolysis of acetylthiocholine. The calculated beta-deuterium isotope effect for equilibrium addition of methanol to methyl thioacetate is D3Keq = 0.965, and the corresponding effect for addition of methoxide ion to methyl thioacetate wherein three waters are hydrogen bonded to the carbonyl oxyanion is D3Keq = 1.086. Neither of these calculated isotope effects is as inverse as the experimental beta-deuterium isotope effect for acetylcholinesterase-catalyzed hydrolysis of acetylthiocholine, D3kE = 0.90š0.03. Structural comparisons show that the water-solvated methoxide adduct of methyl thioacetate is more expanded than is the neutral methanol addition adduct, and suggest that the degree to which the isotope effect is inverse (i.e. less than) is inversely correlated to the degree of expansion of the adduct. A similar correlation of beta-deuterium and beta-deuterium secondary isotope effects with the degree of expansion of the adducts is found for equilibrium additions of methanol and methoxide ion to acetaldehyde. These computational results suggest that the markedly inverse beta-deuterium isotope effect for the acetylcholinesterase reaction arises from enzymic compression of the transition state.
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