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Nucleospora salmonis (Hedrick, Groff et Baxa, 1991), an intranuclear microsporidian parasite of marine and freshwater fish, causes diseases mainly in salmonid species. Losses have been reported in stocks of salmonid fish reared in the region of Auvergne (France). The cause of chronic mortalities in the local host species raised in aquaculture and destined for supplementation of the river system Loire-Allier was examined. The presence of N. salmonis was confirmed by PCR and histology in Salmo salar L. previously and in newly investigated salmonid species, Salmo salar, Salmo trutta fario L., Thymallus thymallus (L.) and Salvelinus alpinus (L.), present in European streams. The infection by N. salmonis was consistent in all cases with characteristic symptoms of the disease in deceased or moribund fish. The small subunit ribosomal DNA from N. salmonis was partially sequenced and compared to previously characterised N. salmonis isolates. As a result, a genotype, or clonal entity, was attributed to N. salmonis among Atlantic salmon found along the Northern Atlantic coastal lines and other salmonid species co-inhabiting or co-cultivated in the Auvergne region. 相似文献
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Bülent E. Erenoglu Hemanta K. Patra Hicham Khodr Volker Römheld Nicolaus von Wirén 《植物养料与土壤学杂志》2007,170(6):788-795
Increasing the mobilization and root uptake of chromium (Cr) by synthetic and plant‐borne chelators might be relevant for the design of phytoremediation strategies on Cr‐contaminated sites. Short‐term uptake studies in maize roots supplied with 51CrCl3 or 51Cr(III)‐EDTA led to higher apoplastic Cr contents in plant roots supplied with 51CrCl3 and in Fe‐sufficient plants relative to Fe‐deficient plants, indicating that Fe stimulated co‐precipitation of Cr. Concentration‐dependent retention of Cr in a methanol:chloroform‐treated cell‐wall fraction was still saturable and in agreement with the predicted tendency of Cr(III) to precipitate as Cr(OH)3. To investigate a possible stimulation of Cr(III) uptake by phytosiderophores, Fe‐deficient maize roots were exposed for 6 d to Cr(III)‐EDTA or Cr(III)‐DMA (2'‐deoxymugineic acid). Relative to plants without Cr supply, the supply of both chelated Cr species in a subtoxic concentration of 1 µM resulted in alleviation of Fe deficiency–induced chlorosis and higher Cr accumulation. Long‐term Cr accumulation from Cr(III)‐DMA was similar to that from Cr(III)‐EDTA, and Cr uptake from both chelates was not altered in the maize mutant ys1, which is defective in metal‐phytosiderophore uptake. We therefore conclude that phytosiderophores increase Cr solubility similar to synthetic chelators like EDTA, but do not additionally contribute to Cr(III) uptake from Cr‐contaminated sites. 相似文献
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Benabdelkamel H Di Donna L Mazzotti F Naccarato A Sindona G Tagarelli A Taverna D 《Journal of agricultural and food chemistry》2012,60(14):3717-3726
Clementine is a citrus fruit that has found a peculiar habitat in specific areas of Calabria, a region located in southern Italy. Due to its peculiar characteristics it was recently awarded with protected geographical indications (PGI) from the European Union. In this work, stepwise linear discriminant analysis (S-LDA), soft independent modeling of class analogy (SIMCA), and partial least-squares discriminant analysis (PLS-DA) were used to build chemometric models able to protect PGI Clementine from others of different origin. Accordingly, the concentration of 24-26 elements was determined in peel and juice samples, respectively, obtained from Calabrian PGI clementine and from fruits cultivated in Algeria, Tunisia, and Spain. A cross-validation procedure has shown very satisfactory values of prediction ability for both S-LDA (96.6% for juice samples and 100% for peel samples) and SIMCA (100% for both peel and juice samples). PLS-DA models also yielded satisfactory results. 相似文献
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Naylo Ahmed Almeida Pereira Sofia I. Benidire Leila El Khalil Hicham Castro Paula M. L. Ouvrard Stéphanie Schwartz Christophe Boularbah Ali 《Journal of Soils and Sediments》2019,19(5):2153-2165
Journal of Soils and Sediments - Due to their close proximity with the population, urban soils are extensively affected by human activities that release considerable technogenic inputs resulting in... 相似文献
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Macrophage lipid accumulation induced by low density lipoproteins (LDL) plays a pivotal role in atherosclerotic plaque development. Previous work showed that Ocimum basilicum extract, used as hypocholesterolemic agent by traditional medicine in Morocco, has hypolipidemic activity in rat acute hyperlipimidemia. This study investigated the effects of ethanolic extract of O. basilicum on lipid accumulation in human macrophages. As modification of LDL increase atherogenicity of the particles we evaluated the effects of the extract on LDL oxidation. The extract caused a dose-related increase of LDL-resistance to Cu(2+)-induced oxidation. Furthermore, at the dose of 60 microg/ml, significantly decreases the accumulation of macrophage lipid droplets induced by modified LDL evaluated as by red-oil staining. Cholesterol esterification and triacylglycerol synthesis in the cells were not affected. Macrophage treatment with 60 microg/ml, but not 20 microg/ml, of the extract reduced newly synthesized unesterified cholesterol by about 60% and decreased scavenger receptors activity by about 20-30%, evaluated by the internalization of cholesterol carried by [(3)H]CE-aggregated-LDL. The results suggest that O. basilicum ethanolic extract has the capability to reduce foam cell formation through the reduction of cholesterol synthesis and the modulation of the activity of surface scavenger receptors. 相似文献
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Distribution of major elements and trace metals as indicators of technosolisation of urban and suburban soils 总被引：2，自引：2，他引：0
Hicham El Khalil Christophe Schwartz Ouafae El Hamiani Jochen Kubiniok Jean Louis Morel Ali Boularbah 《Journal of Soils and Sediments》2013,13(3):519-530
Purpose
Can geochemical characteristics indicate the human impact on soil formation (technosolisation) for urban and suburban soils? This question is assessed for the city of Marrakech located in one of the main agricultural areas of Morocco and characterized by a very rapid rate of expansion. The aim of this work is to assess geochemical properties of surface horizons of urban and suburban soils and to compare them with land use types.Materials and methods
Fifty-eight surface soil samples were collected in different sectors of the city with different land use histories. As land use can be defined as the human use of land, these sampling sites were selected according to the current human activity (e.g., residential districts, agriculture, market-gardening, traditional, or industrial activities) and according to the superposition of the land use over time. All samples were air-dried, disaggregated, homogenized, and then sieved through a 2-mm mesh. Major elements and trace metals were measured in the soil using X-ray fluorescence spectroscopy. For technical limits, Cd was measured using atomic adsorption spectrometry.Results and discussion
Urban and suburban soils of Marrakech present generally similar geochemical compositions for many elements. Siliceous (SiO2) compounds related to the parent material are dominant in these soils. However, the significant concentrations of P2O5 and CaO, measured in some of the urban soils studied, can be attributed to anthropogenic inputs of phosphorus (P) and technic materials, mainly building materials composed of cement and gypsum (plaster). Soils collected from agricultural areas irrigated with urban wastewater and soils developed on rubbish dumps are the most contaminated by metals (e.g., Cu, Zn, and Pb). Therefore, the distribution of major and trace elements in soils underlines the considerable impact of urban land uses.Conclusions
Human activities determine the type of land use, impact the urban environment, and cause a wide spatial diversity of soil quality. The urban and suburban soils of Marrakech contain similar major element distributions except for strongly anthropised soils (soils developed on rubbish dumps and agricultural soils irrigated with urban wastewater). Unlike major elements, trace elements present systematically significantly higher concentrations in urban soils than those measured in control soils. In these conditions, the highest concentrations exceed international clean-up standards and are correlated with land use type. Phosphorus, Ca, and several heavy metals are proposed as indicators of human impacts on soil characteristics in urban and suburban environments. 相似文献19.
Minh Hong Anh Le Sarabjeet Singh Suri Felaniaina Rakotondradany Hicham Fenniri Baljit Singh 《Veterinary research》2010,41(5)
Migration of activated neutrophils that have prolonged lifespan into inflamed organs is an important component of host defense but also contributes to tissue damage and mortality. In this report, we used biologically-inspired RGD-tagged rosette nanotubes (RNT) to inhibit neutrophil chemotaxis. We hypothesize that RGD-RNT will block neutrophil migration through inhibition of MAPK. In this report, RNT conjugated to lysine (K–RNT) and arginine-glycine-aspartic acid-serine-lysine (RGDSK-RNT) were co-assembled in a molar ratio of 95/5. The effect of the resulting composite RNT (RGDSK/K–RNT) on neutrophil chemotaxis, cell signaling and apoptosis was then investigated. Exposure to RGDSK/K–RNT reduced bovine neutrophil migration when compared to the non-treated group (p < 0.001). Similar effect was seen following treatment with ERK1/2 or p38 MAPK inhibitors. Phosphorylation of the ERK1/2 and p38 MAPK was inhibited at 5 min by RGDSK/K–RNT (p < 0.05). The RGDSD/K-RNT did not affect the migration of neutrophils pre-treated with αvβ3 integrin antibody suggesting that both bind to the same receptor. RGDSK/K–RNT did not induce apoptosis in bovine neutrophils, which was suppressed by pre-exposing them to LPS (p < 0.001). We conclude that RGDSK/K–RNT inhibit phosphorylation of ERK1/2 and p38 MAPK and inhibit chemotaxis of bovine neutrophils. 相似文献
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The quantitative distribution of dominant phytoplankton species was carried out in the stabilisation ponds of Etueffont landfill leachate (Belfort, France) from May 1998 to May 1999. The results showed maximum phytoplankton abundance in the last lagooning basin during summer 1998, that coincided with an increase in temperature and better leachate quality. In addition, the phytoplankton was dominated by Euglenophytes species Phacus sp. and Euglena sp. known to resist constraints induced by the highly polluted aquatic environments. An improve in water quality of the last basins translated into a shift in species composition with the substitution of the Bacillariophyceae (Stephanodiscus dubius) by the Chlorophyceae (Coelastrum sp.). 相似文献