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Isolation of 12 microsatellite markers following a pyrosequencing procedure and cross-priming in two invasive cryptic species, Alexandrium catenella (group IV) and A. tamarense (group III) (Dinophyceae) Полный текст
2014
Laporte, Martin | Shao, Zhaojun | Berrebi, Patrick | Laabir, Mohamed | Abadie, Eric | Faivre, Nicolas | Rieuvilleneuve, Fabien | Masseret, Estelle
Isolation of 12 microsatellite markers following a pyrosequencing procedure and cross-priming in two invasive cryptic species, Alexandrium catenella (group IV) and A. tamarense (group III) (Dinophyceae) Полный текст
2014
Laporte, Martin | Shao, Zhaojun | Berrebi, Patrick | Laabir, Mohamed | Abadie, Eric | Faivre, Nicolas | Rieuvilleneuve, Fabien | Masseret, Estelle
Alexandrium catenella (group IV) and Alexandrium tamarense (group III) (Dinophyceae) are two cryptic invasive phytoplankton species belonging to the A. tamarense species complex. Their worldwide spread is favored by the human activities, transportation and climate change. In order to describe their diversity in the Mediterranean Sea and understand their settlements and maintenances in this area, new microsatellite markers were developed based on Thau lagoon (France) samples of A. catenella and A. tamarense strains. In this study twelve new microsatellite markers are proposed. Five of these microsatellite markers show amplifications on A. tamarense and ten on A. catenella. Three of these 12 microsatellite markers allowed amplifications on both cryptic species. Finally, the haplotypic diversity ranged from 0.000 to 0.791 and 0.000 to 0.942 for A. catenella and A. tamarense respectively.
Показать больше [+] Меньше [-]Isolation of 12 microsatellite markers following a pyrosequencing procedure and cross-priming in two invasive cryptic species, Alexandrium catenella (group IV) and A. tamarense (group III) (Dinophyceae) Полный текст
2014
Laporte, Martin | Shao, Zhaojun | Berrebi, Patrick | Laabir, Mohamed | Abadie, Eric | Faivre, Nicolas | Rieuvilleneuve, Fabien | Masseret, Estelle
Alexandrium catenella (group IV) and Alexandrium tamarense (group III) (Dinophyceae) are two cryptic invasive phytoplankton species belonging to the A. tamarense species complex. Their worldwide spread is favored by the human activities, transportation and climate change. In order to describe their diversity in the Mediterranean Sea and understand their settlements and maintenances in this area, new microsatellite markers were developed based on Thau lagoon (France) samples of A. catenella and A. tamarense strains. In this study twelve new microsatellite markers are proposed. Five of these microsatellite markers show amplifications on A. tamarense and ten on A. catenella. Three of these 12 microsatellite markers allowed amplifications on both cryptic species. Finally, the haplotypic diversity ranged from 0.000 to 0.791 and 0.000 to 0.942 for A. catenella and A. tamarense respectively.
Показать больше [+] Меньше [-]Metallothioneins pattern during ontogeny of coastal dolphin, Pontoporia blainvillei, from Argentina Полный текст
2014
Polizzi, P.S. | Romero, M.B. | Chiodi Boudet, L.N. | Das, K. | Denuncio, P.E. | Rodríguez, D.H. | Gerpe, M.S.
Metallothioneins pattern during ontogeny of coastal dolphin, Pontoporia blainvillei, from Argentina Полный текст
2014
Polizzi, P.S. | Romero, M.B. | Chiodi Boudet, L.N. | Das, K. | Denuncio, P.E. | Rodríguez, D.H. | Gerpe, M.S.
Metallothioneins are signals of metal exposure and widely used in biomonitoring. Franciscana dolphin is an endemic cetacean from the Southwestern Atlantic Ocean, classified as Vulnerable A3d by the IUCN. Metallothionein, copper and zinc in Franciscana were assessed in two geographic groups; one inhabits La Plata River estuary, anthropogenically impacted, and the other inhabits marine coastal ecosystems, with negligible pollution. Despite the environment, hepatic and renal MT concentrations were similar, but there was a declining trend from early to later developmental stages. Metallothionein K/L, Cu and Zn levels corresponded to normal reported ranges. MT was not related with Cd. Fetal concentrations were higher than its mother. These results and the health status of dolphins are suggesting that MT correspond to physiological ranges for the species, and they are closely to homeostasis of Zn and Cu, according to its ontogenetic changes. The information constitutes the first MT information on Franciscana dolphin and can be considered as baseline for the species conservation.
Показать больше [+] Меньше [-]Metallothioneins pattern during ontogeny of coastal dolphin, Pontoporia blainvillei, from Argentina Полный текст
2014
Polizzi, P.S. | Romero, M.B. | Chiodi Boudet, L.N. | Das, Krishna | Denuncio, P.E. | Rodriguez, D.H. | Gerpe, M.S.
peer reviewed | Metallothioneins are signals of metal exposure and widely used in biomonitoring. Franciscana dolphin is an endemic cetacean from the Southwestern Atlantic Ocean, classified as Vulnerable A3d by the IUCN. Metallothionein, copper and zinc in Franciscana were assessed in two geographic groups; one inhabits La Plata River estuary, anthropogenically impacted, and the other inhabits marine coastal ecosystems, with negligible pollution. Despite the environment, hepatic and renal MT concentrations were similar, but there was a declining trend from early to later developmental stages. Metallothionein K/L, Cu and Zn levels corresponded to normal reported ranges. MT was not related with Cd. Fetal concentrations were higher than its mother. These results and the health status of dolphins are suggesting that MT correspond to physiological ranges for the species, and they are closely to homeostasis of Zn and Cu, according to its ontogenetic changes. The information constitutes the first MT information on Franciscana dolphin and can be considered as baseline for the species conservation.
Показать больше [+] Меньше [-]Temperature extremes reduce seagrass growth and induce mortality Полный текст
2014
Collier, C.J. | Waycott, M.
Temperature extremes reduce seagrass growth and induce mortality Полный текст
2014
Collier, C.J. | Waycott, M.
Extreme heating (up to 43°C measured from five-year temperature records) occurs in shallow coastal seagrass meadows of the Great Barrier Reef at low tide. We measured effective quantum yield (ϕPSII), growth, senescence and mortality in four tropical seagrasses to experimental short-duration (2.5h) spikes in water temperature to 35°C, 40°C and 43°C, for 6 days followed by one day at ambient temperature. Increasing temperature to 35°C had positive effects on ϕPSII (the magnitude varied between days and was highly correlated with PPFD), with no effects on growth or mortality. 40°C represented a critical threshold as there were strong species differences and there was a large impact on growth and mortality. At 43°C there was complete mortality after 2–3days. These findings indicate that increasing duration (more days in a row) of thermal events above 40°C is likely to affect the ecological function of tropical seagrass meadows.
Показать больше [+] Меньше [-]Temperature extremes reduce seagrass growth and induce mortality Полный текст
2014
Collier, C. | Waycott, M.
Abstract not available | C.J. Collier, M. Waycott
Показать больше [+] Меньше [-]Molecular biomarkers in grey seals (Halichoerus grypus) to evaluate pollutant exposure, health and immune status Полный текст
2014
Lehnert, K. | Muller, S. | Weirup, L. | Ronnenberg, K. | Pawliczka, I. | Rosenberger, T. | Siebert, U.
Molecular biomarkers in grey seals (Halichoerus grypus) to evaluate pollutant exposure, health and immune status Полный текст
2014
Lehnert, K. | Muller, S. | Weirup, L. | Ronnenberg, K. | Pawliczka, I. | Rosenberger, T. | Siebert, U.
Grey seals as top-predators bioaccumulate contaminants and can be considered as sentinels of eco-system health. Pups are weaned after a short nursing period, characterised by an enormous lipid transfer and exposure to contaminants. This study established molecular biomarkers of the xenobiotic metabolism and immune system to help assess health and immune status. mRNA transcription of AHR, ARNT, PPARα and cytokine IL-2 and heat-shock-protein HSP70 was measured in blood of grey seal pups and adults in rehabilitation and permanent care using RT-qPCR and compared to rehabilitating harbour seal pups and haematology values. In pups highest levels at admission in xenobiotic biomarker, HSP70 and cytokine transcription may show contaminant exposure via lactation, stress during abandonment and dehydration. The significant decrease may be linked to diet, health improvement and adaptation. Adults showed higher levels and more variation in biomarker transcription and clear species-specific differences between harbour and grey seal pups were found.
Показать больше [+] Меньше [-]Molecular biomarkers in grey seals (Halichoerus grypus) to evaluate pollutant exposure, health and immune status Полный текст
2014
Lehnert, Kristina | Müller, Sabine | Weirup, Lina | Ronnenberg, Katrin | Pawliczka vel Pawlik, Iwona Joanna | Rosenberger, Tanja | Siebert, Ursula
Grey seals as top-predators bioaccumulate contaminants and can be considered as sentinels of ecosystem health. Pups are weaned after a short nursing period, characterised by an enormous lipid transfer and exposure to contaminants. This study established molecular biomarkers of the xenobiotic metabolism and immune system to help assess health and immune status. mRNA transcription of AHR, ARNT, PPAR~a and cytokine IL-2 and heat-shock-protein HSP70 was measured in blood of grey seal pups and adults in rehabilitation and permanent care using RT-qPCR and compared to rehabilitating harbour seal pups and haematology values. In pups highest levels at admission in xenobiotic biomarker, HSP70 and cytokine transcription may show contaminant exposure via lactation, stress during abandonment and dehydration. The significant decrease may be linked to diet, health improvement and adaptation. Adults showed higher levels and more variation in biomarker transcription and clear species-specific differences between harbour and grey seal pups were found.
Показать больше [+] Меньше [-]The use of cholinesterase as potential biomarker: In vitro characterization in the polychaete Capitella teleta Полный текст
2014
Gomes, Isa D.L. | Lemos, Marco F.L. | Soares, Amadeu M.V.M. | Barata, Carlos | Faria, Melissa
The use of cholinesterase as potential biomarker: In vitro characterization in the polychaete Capitella teleta Полный текст
2014
Gomes, Isa D.L. | Lemos, Marco F.L. | Soares, Amadeu M.V.M. | Barata, Carlos | Faria, Melissa
The ecological relevance of polychaetes coupled with their easy culture and maintenance in the laboratory, has led them to become increasingly used in marine ecotoxicological studies, raising the need to validate frequently applied monitoring tools at various biological levels. The present study was aimed to characterize the cholinesterases (ChE) activity in the polychaete Capitella teleta, using three substrates (acetylthiocholine iodide, propionylthiocholine iodide, and S-butyrylthiocholine iodide) and four known inhibitors (eserine hemisulfate, BW284c51, iso-OMPA and chlorpyrifos-oxon). Results showed that most of the measured cholinesterase activity was acetylcholinesterase (AChE). Inhibition of enzyme kinetic experiments denoted that sensitivity of C. teleta’s ChE to the organophosphorous metabolite chlorpyrifos-oxon (IC50=60.72nM) was analogous to some fish species. This study highlights the relevance of ChE characterization before its use as a biomarker in ecotoxicology and biomonitoring studies.
Показать больше [+] Меньше [-]The use of cholinesterase as potential biomarker: in vitro characterization in the polychaete Capitella teleta Полный текст
1000
Gomes, Isa D. L. | Lemos, Marco F. L. | Soares, Amadeu M. V. M. | Barata, Carlos | Faria, Melissa
The ecological relevance of polychaetes coupled with their easy culture and maintenance in the laboratory, has led them to become increasingly used in marine ecotoxicological studies, raising the need to validate frequently applied monitoring tools at various biological levels. The present study was aimed to characterize the cholinesterases (ChE) activity in the polychaete Capitella teleta, using three substrates (acetylthiocholine iodide, propionylthiocholine iodide, and S-butyrylthiocholine iodide) and four known inhibitors (eserine hemisulfate, BW284c51, iso-OMPA and chlorpyrifos-oxon). Results showed that most of the measured cholinesterase activity was acetylcholinesterase (AChE). Inhibition of enzyme kinetic experiments denoted that sensitivity of C. teleta's ChE to the organophosphorous metabolite chlorpyrifos-oxon (IC50=60.72nM) was analogous to some fish species. This study highlights the relevance of ChE characterization before its use as a biomarker in ecotoxicology and biomonitoring studies.
Показать больше [+] Меньше [-]The larvae of congeneric gastropods showed differential responses to the combined effects of ocean acidification, temperature and salinity Полный текст
2014
The larvae of congeneric gastropods showed differential responses to the combined effects of ocean acidification, temperature and salinity Полный текст
2014
The tolerance and physiological responses of the larvae of two congeneric gastropods, the intertidal Nassarius festivus and subtidal Nassarius conoidalis, to the combined effects of ocean acidification (pCO2 at 380, 950, 1250ppm), temperature (15, 30°C) and salinity (10, 30psu) were compared. Results of three-way ANOVA on cumulative mortality after 72-h exposure showed significant interactive effects in which mortality increased with pCO2 and temperature, but reduced at higher salinity for both species, with higher mortality being obtained for N. conoidalis. Similarly, respiration rate of the larvae increased with temperature and pCO2 level for both species, with a larger percentage increase for N. conoidalis. Larval swimming speed increased with temperature and salinity for both species whereas higher pCO2 reduced swimming speed in N. conoidalis but not N. festivus. The present findings indicated that subtidal congeneric species are more sensitive than their intertidal counterparts to the combined effects of these stressors.
Показать больше [+] Меньше [-]The larvae of congeneric gastropods showed differential responses to the combined effects of ocean acidification, temperature and salinity Полный текст
2014
Zhang, Haoyu | Cheung, S G | Shin, Paul K S
The tolerance and physiological responses of the larvae of two congeneric gastropods, the intertidal Nassarius festivus and subtidal Nassarius conoidalis, to the combined effects of ocean acidification (PCO2 at 380, 950, 1250 ppm), temperature (15, 30 degrees C) and salinity (10, 30 psu) were compared. Results of three-way ANOVA on cumulative mortality after 72-h exposure showed significant interactive effects in which mortality increased with pCO(2) and temperature, but reduced at higher salinity for both species, with higher mortality being obtained for N. conoidalis. Similarly, respiration rate of the larvae increased with temperature and pCO(2) level for both species, with a larger percentage increase for N. conoidalis. Larval swimming speed increased with temperature and salinity for both species whereas higher pCO(2) reduced swimming speed in N. conoidalis but not N. festivus. The present findings indicated that subtidal congeneric species are more sensitive than their intertidal counterparts to the combined effects of these stressors. (c) 2014 Elsevier Ltd. All rights reserved.
Показать больше [+] Меньше [-]Trace element contamination in the Guadalquivir River Estuary ten years after the Aznalcóllar mine spill Полный текст
2014
Tornero, Victoria | Arias, Alberto M. | Blasco, Julián
Trace element contamination in the Guadalquivir River Estuary ten years after the Aznalcóllar mine spill Полный текст
2014
Tornero, Victoria | Arias, Alberto M. | Blasco, Julián
Sediments, clams Scrobicularia plana and worms Hediste diversicolor from the Guadalquivir estuary were collected ten years after the Aznalcóllar mine spill and analyzed for metals. Significant seasonal and spatial effects were detected for most elements, so data from different sampling periods and locations were treated separately. Overall, the most polluted sites were found upstream, although Zn and Cu tended to accumulate at the estuary mouth. A significant decline of Zn in sediments and clams was observed compared to levels reported following the spill, so the estuarine ecosystem has recovered. However, the concentrations of some elements in S. plana were still higher than those of heavily contaminated regions. In this mollusk, Pb and As levels were higher in 2008 than in previous years, suggesting a new source entering into the estuary. Metals in sediments presented low bioavailability for biota, so other sources must account for the concentrations observed in these species.
Показать больше [+] Меньше [-]Trace element contamination in the Guadalquivir River Estuary ten years after the Aznalcóllar mine spill Полный текст
2014
Tornero, Victoria | Arias, Alberto M. | Blasco, Julián | European Commission | Ministerio de Ciencia y Tecnología (España)
Sediments, clams Scrobicularia plana and worms Hediste diversicolor from the Guadalquivir estuary were collected ten years after the Aznalcóllar mine spill and analyzed for metals. Significant seasonal and spatial effects were detected for most elements, so data from different sampling periods and locations were treated separately. Overall, the most polluted sites were found upstream, although Zn and Cu tended to accumulate at the estuary mouth. A significant decline of Zn in sediments and clams was observed compared to levels reported following the spill, so the estuarine ecosystem has recovered. However, the concentrations of some elements in S. plana were still higher than those of heavily contaminated regions. In this mollusk, Pb and As levels were higher in 2008 than in previous years, suggesting a new source entering into the estuary. Metals in sediments presented low bioavailability for biota, so other sources must account for the concentrations observed in these species. | While doing this work, V. Tornero was fully supported by a I3P contract from the Programa Nacional de Potenciación de Recursos Humanos del Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (2000–2003). The presented study was supported as a part of the projects CTM2005-07282-C03-02/TECNO (Spanish Science and Technology National Plan) and Interreg IIIA REDCONTAMAR SP5 (SP3.E101/03). | Peer reviewed
Показать больше [+] Меньше [-]The origin of the Ulva macroalgal blooms in the Yellow Sea in 2013 Полный текст
2014
Zhang, Jianheng | Huo, Yuanzi | Wu, Hailong | Yu, Kefeng | Kim, Jang Kyun | Yarish, Charles | Qin, Yutao | Liu, Caicai | Xu, Ren | He, Peimin
Green algal blooms have occurred in the Yellow Sea for seven consecutive years from 2007 to 2013. In this study, satellite image analysis and field shipboard observations indicated that the Ulva blooms in 2013 originated in the Rudong coast. The spatial distribution of Ulva microscopic propagules in the Southern Yellow Sea also supported that the blooms originated in the Rudong coast. In addition, multi-source satellite data were used to evaluate the biomass of green algae on the Pyropia aquaculture rafts. The results showed that approximately 2784 tons of Ulva prolifera were attached to the rafts and possessed the same internal transcribed spacer and 5S rDNA sequence as the dominant species in the 2013 blooms. We conclude that the significant biomass of Ulva species on the Pyropia rafts during the harvesting season in radial tidal sand ridges played an important role in the rapid development of blooms in the Yellow Sea.
Показать больше [+] Меньше [-]Organic matter and pyritization relationship in recent sediments from a tropical and eutrophic bay Полный текст
2014
Sabadini-Santos, Elisamara | Senez, Thaise M. | Silva, Tabatta S. | Moreira, Manuel R. | Mendonça-Filho, João Graciano | Santelli, Ricardo E. | Crapez, Mirian A.C.
The degree of pyritization (DOP) and the extension of metals incorporation into pyrite was investigated at Guanabara Bay sediments. Maximum concentrations of total organic carbon (TOC), total sulfur, biopolymers and viable bacteria cells were observed in silted stations close to discharge points of sewage and minimum concentrations at sandy stations at the entrance of the bay. Pyrite iron concentrations (Fepy) was always lower than the reactive iron and Fepy were below the detection limit at sandy stations. The same trend was found to metals, which its degree of pyritization was Mn=Cu>As=Co>Ni>Cd>Zn≫Pb>Cr. The bay gathers all required factors to sulfate reduction and pyrite formation, once the C:S ratio express the reduced tendency conditions, almost half of the TOC present in its sediments is labile and both reactive sulfur and iron are available. However the degree of trace metals pyritization did not exceed 20%, consistent with the median DOP (29%).
Показать больше [+] Меньше [-]Macrobenthic succession and characteristics of a man-made intertidal sandflat constructed in the diversion channel of the Ohta River Estuary Полный текст
2014
Nishijima, Wataru | Nakano, Yoichi | Nakai, Satoshi | Okuda, Tetsuji | Imai, Tsuyoshi | Okada, Mitsumasa
We compared succession and characteristics of the macrobenthic community in a small-scale experimental intertidal sandflat constructed in the artificial diversion channel of the Ohta River Estuary with those of three natural intertidal sandflats at lower elevation in the same channel. The macrobenthic population density in the man-made intertidal sandflat increased significantly between 3 and 9months after construction. Simplisetia erythraeensis was dominant (98% of individuals) after 9months, but its proportion gradually declined with the increase in biodiversity until 26months, indicating that succession of the macrobenthic community was nearly complete by 26months. The macrobenthic community in the man-made intertidal sandflat differed from those of the three natural intertidal sandflats, and its population density was about double that at the natural sites, with smaller temporal fluctuation. The different structures of the macrobenthic communities in the man-made and natural intertidal sandflats were likely caused by differences in elevation.
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