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Concentrations of cadmium, copper, iron, lead, manganese, nickel and zinc were investigated in two species of mussel from the Kuril Islands in the north-western Pacific Ocean: the short-lived mussel Mytilus trossulus and the much larger and longer-lived Crenomytilus grayanus. The concentrations of most elements were low, and these reported levels are believed to reflect background values for pristine locations. However, both iron and zinc concentrations were elevated in some samples taken from areas of hydrothermal vent activity, and these are believed to reflect the enrichment of the two metals in solution at such sites. Furthermore, the concentrations of cadmium were unusually elevated in both species of mussel, especially in the longer-lived C. grayanus. The high accumulation of cadmium in mussels from the Kuril Islands is believed to reflect regional upwelling, but it is also postulated that filtration rates of the mussels are high due to low levels of suspended matter, and this leads to a high assimilation efficiency for cadmium. The distribution of cadmium amongst the tissues of C. grayanus is also reported, and the need for further ecotoxicological studies in the area is proposed. 相似文献
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Cd, Cu, Fe, Mn, Ni, Pb, Zn concentration in the organs (muscle, gonads, mantle, gills, digestive gland, kidney) of mussel Modiolus modiolus was studied. Mussels were collected from shelf upwelling sites of Kuril Is. Sea of Okhotsk (104 and 85 m) and, for comparison, coastal high contaminated and clean sites (Peter the Great Bay, Sea of Japan). It was found that mussels from shelf upwelling regions accumulated unusually high Cd concentration in studied organs, excepting digestive gland. Shelf mussels have evolved passive adaptation to elevated level of ambient heavy metals (distribution of heavy metal load between all organs, especially, muscle). In contrast, mussels from high contaminated sites have evolved active adaptation (strong regulation of metal concentration in the organs at the maximal permissible concentration due to increased kidney function). We supported that under natural condition, passive adaptation of aquatic organisms to increased ambient metal level have been evolved only under constant low-water temperature. 相似文献
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R. B. SCORZELLI M. CHRISTOPHE MICHEL-LVY E. GILABERT B. LAVIELLE I. SOUZA AZEVEDO V. W. VIEIRA T. V. V. COSTA M. A. B. ARAÚJO 《Meteoritics & planetary science》1998,33(6):1335-1337
Abstract— The Campos Sales meteorite fell close to the town of Campos Sales in the northeastern Brazilian state of Ceará (7°2′ S, 40°10′ W) on 1991 January 31 at 10:00 P.M. (local time). Several fragments were recovered from an area estimated to be 1 × 3 km. The stone is an ordinary L5 chondrite (Fa25.0 and FS21.6) and is lightly shocked (S1). Metal phases present are kamacite, tetrataenite, and antitaenite. Noble gases He, Ne, Ar, Kr, and Xe have been analyzed in two bulk samples of Campos Sales. All exposure ages based on determination of cosmogenic 3He, 21Ne, 38Ar, 83Kr, and 126Xe abundances and on the cosmogenic 81Kr/83Kr ratio agree well, which suggests no gas loss during cosmic-ray exposure. The cosmic-ray exposure age is 23.3 ± 1.0 Ma, which falls in the range observed for L5 chondrites (20–30 Ma). The gas-retention ages indicate He loss that must have occurred prior to or during ejection from the L-chondrite parent body. 相似文献
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Nina N. Belcheva Maxim V. Zakhartsev Nadezhda V. Dovzhenko Avianna F. Zhukovskaya Victor Ya. Kavun Victor P. Chelomin 《Ocean Science Journal》2011,46(2):85-94
The digestive gland and gills of the mussel Crenomytilus grayanus extracted from three locations — (i) sampled from a clean and (ii) polluted site and (iii) transplanted from the nonpolluted
to polluted site - were analysed for antioxidant enzymes (superoxide dismutase, catalase, glutathione reductase), total oxyradical
scavenging capacity and levels of lipid peroxidation products (malondialdehyde, conjugated dienes and lipofuscin). Perturbation
of redox status was found in both digestive gland and gill tissues of mussels living in the polluted area. As the activities
of superoxide dismutase and catalase were 1.2–3 times higher, the total oxyradical scavenging capacity was lower by 20–35%
and the levels of lipid peroxidation products were 2–7 times higher compared to mussels from the reference site. In transplanted
mussels, the lipid peroxidation process in both tissues was significantly stimulated (the level of conjugated dienes was increased
1.7–2.5-fold; malondialdehyde and lipofuscin contents were increased 3.5–5-fold) and the total oxyradical scavenging capacity
fell by 50–70%. In addition, the transplantation generally resulted in transient and variable responses of antioxidant enzymes
for both tissues. Complex response-behaviour of the antioxidant enzymes strongly points to the necessity of employing a combined
approach that takes into account activities of antioxidant enzymes and the total oxyradical scavenging capacity, as well as
measurement of oxidative damage (e.g., lipid peroxidation) to evaluate the physiological health of molluscs. 相似文献
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Concentration and distribution of Fe, Zn, Cu, Cd, Mn, Pb, Ni among subcellular fractions (cellular membrane structures and
cytosol) and Zn, Cu, Cd among cytoplasmic proteins in the kidney and digestive gland of musselModiolus modiolus living along a polymetallic concentration gradient were studied. It was found in the kidney ofM. modiolus from contaminated sites that the Fe percent increased in the “membrane” fraction, whereas Zn, Pb, Ni and Mn percent increased
in the cytosol compared to the kidney of the control mussel. Note kidney cytosol ofM. modiolus from clean and contaminated sites sequestered major parts of Cu and Cd. In the digestive gland ofM. modiolus from contaminated sites Fe, Zn, Cd, Mn, Ni percent increased in the “membrane” fraction, whereas Cu, Pb percent increased
in the cytosol compared to digestive gland of control mussel. Gel-filtration chromatography shows kidney ofM. modiolus contains increased metallothionein-like protein levels irrespective of ambient dissolved metal concentrations. It was shown
that the metal detoxification system in the kidney and digestive gland ofM. modiolus was efficient under extremely high ambient metal levels. However, under complex environmental contamination in the kidney
ofM. modiolus, the metal detoxification capacity of metallothionein-like proteins was damaged. 相似文献
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N. K. Khristoforova V. Ya. Kavun Yu. Ya. Latypov Dam Dook Tien E. V. Zhuravel’ Nguen Xuan Tuyan 《Oceanology》2007,47(5):685-690
To characterize the terrigenous, anthropogenic, and technogenous impacts upon the ecosystems of coral reefs in the shallow-water Ha Long Bay, which was declared by UNESCO to be a world natural heritage site, the levels of Fe, Mn, Zn, Cd, Pb, and Ni in the soft tissues of six mass species of bivalve mollusks from island coastal waters were studied. Taking into account the abundance and distribution, as well as the capability to represent the geochemical conditions of the environment, for further biomonitoring of heavy metal contents in the coastal waters of the bay, the following species were recommended: Septifer binocularis, Barbatia amygdalumtostum, and Isognomon isognomon. 相似文献
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