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Molecular oxidative stress markers in olive ridley turtles (Lepidochelys olivacea) and their relation to metal concentrations in wild populations النص الكامل
2018
Cortés-Gómez, Adriana A. | Morcillo, Patricia | Guardiola, Francisco A. | Espinosa, Cristobal | Esteban, María A. | Cuesta Arranz, Alberto | Girondot, Marc | Romero, Diego
Due to their longevity and extensive migration areas, marine turtles are able to accumulate diverse contaminants over many years and as a consequence they represent an interesting bioindicator species for marine ecosystem pollution. Metals provoke toxicological effects in many aquatic animal species, but marine turtles have been under-investigated in this area. Thus, we have determined the presence of certain inorganic elements (As, Cd, Cu, Ni, Pb, Se and Zn) in olive ridley turtles (Lepidochelys olivacea) and related them to metallothionein (MT), superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) transcription and/or enzymatic activities. Gene expression of sod, cat and gr was found to be higher in blood than liver or kidney but most of the significant relationships were found in liver, not only for gene expression but also for enzyme activities. This must be related to the role the liver has as the first filter organ. Several positive relationships of sod, cat and gr gene expression in the different tissues were found in this population, as well as very high Cd concentrations. This could mean that these turtles are adapting to the metals-production of ROS and damage through a high transcription of these antioxidants. Multiple positive relationships with GR seem to be part of its compensatory effect due to the decrease of SOD production against the high and chronic exposure to certain xenobiotics. CAT, on the other hand, seems not to be used much, and glutathione detoxification of H₂O₂ may be more important in this species. Finally, despite the very high Cd concentrations found in this population, no significant relationship was found in any tissue with metallothionein gene expression. These results, along with very high Cd concentrations and a negative relationship with Cu, lead us to consider some kind of disruption in mt gene expression in these turtles.
اظهر المزيد [+] اقل [-]Contamination status by persistent organic pollutants of the Atlantic spotted dolphin (Stenella frontalis) at the metapopulation level النص الكامل
2018
Méndez-Fernandez, Paula | Taniguchi, Satie | Santos, Marcos C.O. | Cascão, Irma | Quérouil, Sophie | Martín, Vidal | Tejedor, Marisa | Carrillo, Manuel | Rinaldi, Carolina | Rinaldi, Renato | Montone, Rosalinda C.
The Atlantic spotted dolphin (Stenella frontalis) is an endemic species of the tropical-temperate Atlantic Ocean with widespread distribution. Although this species has been the subject of a large number of studies throughout its range, it remains in the “data deficient” category of the International Union for Conservation of Nature (IUCN). Chemical pollution by persistent organic pollutants (POPs) has been listed as one of the major threats to this species, however, there is no information on a wide scale. Thus, the aim of the present study was to investigate the contamination status of spotted dolphins on the metapopulation level as well as determine spatial and temporal variations in POP concentrations and bio-accumulation. A total of 115 blubber samples collected from a large part of the Atlantic basin were analysed for PCBs, DDTs, PBDEs, chlordanes, HCB and mirex. Although PCBs and DDTs were the predominant compounds in all areas, inter-location differences in POP concentrations were observed. Dolphins found at São Paulo, southeastern coast of Brazil, had the highest PCB concentrations (median: 10.5 μg/g lw) and Canary Islands dolphins had the highest DDT concentrations (median: 5.13 μg/g lw). Differences in PCB patterns among locations were also observed. Dolphins from the Azores and São Paulo demonstrated a similar pattern, with relatively highly contributions of tetra- (6.8 and 5.2%, respectively) and penta-CBs (25.6 and 23.8%, respectively) and lower contributions of hepta-CBs (20.8 and 23.5%, respectively) in comparison to other areas. Moreover, the sex of the animals and the year in which sampling or capture occurred exerted an important influence on the majority of the POPs analysed. Comparisons with toxicity thresholds available in the literature reveal that the São Paulo and Canary Island dolphins are the most vulnerable populations and should be considered in future conservation and management programs for the Atlantic spotted dolphin.
اظهر المزيد [+] اقل [-]Response of edible amaranth cultivar to salt stress led to Cd mobilization in rhizosphere soil: A metabolomic analysis النص الكامل
2018
Guo, Shi-Hong | Hu, Ni | Li, Qu-Sheng | Yang, Ping | Wang, Lili | Xu, Zhi-Min | Chen, Hui-Jun | He, Bao-Yan | Zeng, E. Y. (Eddy Y.)
The present study aimed to investigate the metabolic response of edible amaranth cultivars to salt stress and the induced rhizosphere effects on Cd mobilization in soil. Two edible amaranth cultivars (Amaranthus mangostanus L.), Quanhong (low-Cd accumulator; LC) and Liuye (high-Cd accumulator; HC), were subject to salinity treatment in both soil and hydroponic cultures. The total amount of mobilized Cd in rhizosphere soil under salinity treatment increased by 2.78-fold in LC cultivar and 4.36-fold in HC cultivar compared with controls, with 51.2% in LC cultivar and 80.5% in HC cultivar being attributed to biological mobilization of salinity. Multivariate statistical analysis generated from metabolite profiles in both rhizosphere soil and root revealed clear discrimination between control and salt treated samples. Tricarboxylic acid cycle in root was up-regulated to cope with salinity treatment, which promoted release of organic acids from root. The increased accumulation of organic acids in rhizosphere under salt stress obviously promoted soil Cd mobility. These results suggested that salinity promoted release of organic acids from root and enhanced soil Cd mobilization and accumulation in edible amaranth cultivar in soil culture.
اظهر المزيد [+] اقل [-]In utero exposure to fine particulate matter results in an altered neuroimmune phenotype in adult mice النص الكامل
2018
Kulas, Joshua A. | Hettwer, Jordan V. | Sohrabi, Mona | Melvin, Justine E. | Manocha, Gunjan D. | Puig, Kendra L. | Gorr, Matthew W. | Tanwar, Vineeta | McDonald, Michael P. | Wold, Loren E. | Combs, Colin K.
Environmental exposure to air pollution has been linked to a number of health problems including organ rejection, lung damage and inflammation. While the deleterious effects of air pollution in adult animals are well documented, the long-term consequences of particulate matter (PM) exposure during animal development are uncertain. In this study we tested the hypothesis that environmental exposure to PM 2.5 μm in diameter in utero promotes long term inflammation and neurodegeneration. We evaluated the behavior of PM exposed animals using several tests and observed deficits in spatial memory without robust changes in anxiety-like behavior. We then examined how this affects the brains of adult animals by examining proteins implicated in neurodegeneration, synapse formation and inflammation by western blot, ELISA and immunohistochemistry. These tests revealed significantly increased levels of COX2 protein in PM2.5 exposed animal brains in addition to changes in synaptophysin and Arg1 proteins. Exposure to PM2.5 also increased the immunoreactivity for GFAP, a marker of activated astrocytes. Cytokine concentrations in the brain and spleen were also altered by PM2.5 exposure. These findings indicate that in utero exposure to particulate matter has long term consequences which may affect the development of both the brain and the immune system in addition to promoting inflammatory change in adult animals.
اظهر المزيد [+] اقل [-]Transport and retention of surfactant- and polymer-stabilized engineered silver nanoparticles in silicate-dominated aquifer material النص الكامل
2018
Adrian, Yorck F. | Schneidewind, Uwe | Bradford, Scott A. | Simunek, Jirka | Fernandez-Steeger, Tomas M. | Azzam, R. (Rafig)
Packed column experiments were conducted to investigate the transport and blocking behavior of surfactant- and polymer-stabilized engineered silver nanoparticles (Ag-ENPs) in saturated natural aquifer media with varying content of material < 0.063 mm in diameter (silt and clay fraction), background solution chemistry, and flow velocity. Breakthrough curves for Ag-ENPs exhibited blocking behavior that frequently produced a delay in arrival time in comparison to a conservative tracer that was dependent on the physicochemical conditions, and then a rapid increase in the effluent concentration of Ag-ENPs. This breakthrough behavior was accurately described using one or two irreversible retention sites that accounted for Langmuirian blocking on one site. Simulated values for the total retention rate coefficient and the maximum solid phase concentration of Ag-ENPs increased with increasing solution ionic strength, cation valence, clay and silt content, decreasing flow velocity, and for polymer-instead of surfactant-stabilized Ag-ENPs. Increased Ag-ENP retention with ionic strength occurred because of compression of the double layer and lower magnitudes in the zeta potential, whereas lower velocities increased the residence time and decreased the hydrodynamics forces. Enhanced Ag-ENP interactions with cation valence and clay were attributed to the creation of cation bridging in the presence of Ca2+. The delay in breakthrough was always more pronounced for polymer-than surfactant-stabilized Ag-ENPs, because of differences in the properties of the stabilizing agents and the magnitude of their zeta-potential was lower. Our results clearly indicate that the long-term transport behavior of Ag-ENPs in natural, silicate dominated aquifer material will be strongly dependent on blocking behavior that changes with the physicochemical conditions and enhanced Ag-ENP transport may occur when retention sites are filled.
اظهر المزيد [+] اقل [-]Marine litter in an EBSA (Ecologically or Biologically Significant Area) of the central Mediterranean Sea: Abundance, composition, impact on benthic species and basis for monitoring entanglement النص الكامل
2018
Consoli, Pierpaolo | Andaloro, Franco | Altobelli, Chiara | Battaglia, Pietro | Campagnuolo, Silvana | Canese, Simonepietro | Castriota, Luca | Cillari, Tiziana | Falautano, Manuela | Pedà, Cristina | Perzia, Patrizia | Sinopoli, Mauro | Vivona, Pietro | Scotti, Gianfranco | Esposito, Valentina | Galgani, François | Romeo, Teresa
Marine litter is commonly observed everywhere in the ocean. In this study, we analyzed 17 km of video footage, collected by a Remotely Operated Vehicle (ROV) at depths ranging between 20 and 220 m, during 19 transects performed on the rocky banks of the Straits of Sicily. Recently, the Contracting Parties of the Convention on Biological Diversity (CBD) recognized this site as an Ecologically or Biologically Significant Area (EBSA). The research aim was to quantify the abundance of marine litter and its impact on benthic fauna. Litter density ranged from 0 items/100 m2 to 14.02 items/100 m2 with a mean (±standard error) of 2.13 (±0.84) items/100 m2. The observed average density was higher (5.2 items/100 m2) at depths >100 m than at shallower depths (<100 m, 0.71 items/100 m2). Lost or abandoned fishing lines contributed to 98.07% of the overall litter density, then representing the dominant source of marine debris. Litter interactions with fauna were frequently observed, with 30% of litter causing “entanglement/coverage” and 15% causing damage to sessile fauna. A total of 16 species showed interaction (entanglement/coverage or damage) with litter items and 12 of these are species of conservation concern according to international directives and agreements (CITES, Berne Convention, Habitat Directive, SPA/BD Protocol, IUCN Red List); we also observed 7 priority habitats of the SPA/BD Protocol. This research will support the implementation of monitoring “Harm” as recommended by the UN Environment/MAP Regional Plan on Marine Litter Management in the Mediterranean, and the Marine Strategy Framework Directive (MSFD). The institution of a SPAMI in the investigated area could represent a good management action for the protection of this hotspot of biodiversity and to achieve a Good Environmental Status (GES) for the marine environment by 2020, under the MSFD.
اظهر المزيد [+] اقل [-]Association patterns for size-fractioned indoor particulate matter and black carbon and autonomic function differ between patients with chronic obstructive pulmonary disease and their healthy spouses النص الكامل
2018
Pan, Lu | Dong, Wei | Li, Hongyu | Miller, Mark R. | Chen, Yahong | Loh, Miranda | Wu, Ziyuan | Xu, Junhui | Yang, Xuan | Shima, Masayuki | Deng, Furong | Guo, Xinbiao
The effect of health status on the relationship between particulate matter (PM) and black carbon (BC) and cardiac autonomic function has not been examined sufficiently directly comparing patients with healthy participants.To evaluate the association patterns between size-fractioned indoor PM and BC and cardiac autonomic function in chronic obstructive pulmonary disease (COPD) patients and their healthy spouses.Twenty-four-hour heart rate variability (HRV) and heart rate (HR) was measured in eight pairs of stable COPD patients and their healthy spouses. Real-time size-fractioned indoor PM and BC levels were monitored on the same, and preceding, days. Mixed-effects models were used to estimate the changes in health indices and pollutants after controlling for potential confounding variables.Increases in size-fractioned PM and BC were associated with alterations in cardiac autonomic function in both COPD patients and their healthy spouses. However, the association patterns differed between the two groups. In COPD group, an IQR (13.65 μg/m3) increase in PM0.5 at 12-h moving average was associated with reductions of 14.62% (95% CI: -21.74%, -6.86%) in total power (TP) and 10.14% (95% CI: -16.11%, -3.76%) in high frequency (HF) power. In healthy volunteers, however, TP and HF declined immediately upon exposure to PM and then returned to normal levels gradually. In this group, an IQR increase in PM0.5 at 5 min moving average was associated a 20.30% (95% CI: -25.49%, -14.73%) reduction in TP and a 31.79% (95% CI: -36.48%, -26.72%) reduction in HF.Exposure to indoor PM and BC was associated with cardiac autonomic dysfunction in COPD patients and their healthy spouses. Exposure had a greater lagged effect on HRV in COPD patients than in healthy participants. These findings will aid the formulation of targeted measures to prevent the adverse effects of indoor air pollution for individuals with different health statuses.
اظهر المزيد [+] اقل [-]Chlorinated organic compounds in liquid wastes (DNAPL) from lindane production dumped in landfills in Sabiñanigo (Spain) النص الكامل
2018
Santos, A. | Fernandez, J. | Guadaño, J. | Lorenzo, D. | Romero, A.
α, β and γ-hexachlorocyclohexane (HCH) are persistent and bioaccumulative pollutants and they were included in the Stockholm Convention on Persistent Organic Pollutants (POPs). Old lindane factories generated high amounts of wastes with HCH and other Chlorinated Organic Compounds (COCS). These were often dumped in the surroundings of the production sites, polluting soil and groundwaters with the associated risk of surface pollution. This is the case of the Sardas and Bailin landfills, located in Sabiñánigo (Huesca, Spain). Among the waste from lindane production, a liquid residue was detected in the landfill subsurfaces, forming a dense non-aqueous phase liquid (DNAPL) composed of HCH isomers, benzene and chlorobenzenes, with a high impact on groundwater pollution. In this study, six DNAPL samples obtained from the Bailin and Sardas landfills were analyzed by GC/MSD and GC/FID/ECD. Compounds were identified using mass spectra and the retention index from pure standards and literature information. Pure positional isomers of dichlorobenzene (DCB), trichlorobenzene (TCB), tetrachlorobenzene (TetraCB), HCH and pentachlorocyclohexene (PentaCX) were distinguished and quantified. In addition, heptachlorocyclohexane (HeptaCH) isomers, precursors of hexacholorocylohexene (HexaCX), were also identified and quantified in the DNAPL samples, although the corresponding isomers could not be discriminated. Information about PentaCX, HexaCx and HeptaCH identification is very limited in the literature. HCH contents in the DNAPL ranged from 22% to 30% in weight, the major isomers being lindane and δ-HCH, followed by α-HCH. The β isomer was the least abundant. HeptaCH contents were present in the same order of magnitude as HCHs in the DNAPL. PentaCXs and HexaCXs could have appeared as dehydrochlorination derivatives of HCHs and HeptaCHs, respectively. Two of the DNAPLs analyzed showed a higher content of TCBs and TetraCBs, associated with lower HCH and HeptaCH contents. Variations of these compounds in the DNAPL could be related to an alkaline dehydrochlorination in the landfill conditions.
اظهر المزيد [+] اقل [-]Excessive ER stress and the resulting autophagic flux dysfunction contribute to fluoride-induced neurotoxicity النص الكامل
2018
Niu, Qiang | Chen, Jingwen | Xia, Tao | Li, Pei | Zhou, Guoyu | Xu, Chunyan | Zhao, Qian | Dong, Lixin | Zhang, Shun | Wang, Aiguo
Fluoride is capable of inducing neurotoxicity, but its mechanisms remain elusive. This study aimed to explore the roles of endoplasmic reticulum (ER) stress and autophagy in sodium fluoride (NaF)-induced neurotoxicity, focusing on the regulating role of ER stress in autophagy. The in vivo results demonstrated that NaF exposure impaired the learning and memory capabilities of rats, and resulted in histological and ultrastructural abnormalities in rat hippocampus. Moreover, NaF exposure induced excessive ER stress and associated apoptosis, as manifested by elevated IRE1α, GRP78, cleaved caspase-12 and cleaved-caspase-3, as well as defective autophagy, as shown by increased Beclin1, LC3-II and p62 expression in hippocampus. Consistently, the in vitro results further verified the findings of in vivo study that NaF induced excessive ER stress and defective autophagy in SH-SY5Y cells. Notably, inhibition of autophagy in NaF-treated SH-SY5Y cells with Wortmannin or Chloroquine decreased, while induction of autophagy by Rapamycin increased the cell viability. These results were correlated well with the immunofluorescence observations, thus confirming the pivotal role of autophagic flux dysfunction in NaF-induced cell death. Importantly, mitigation of ER stress by 4-phenylbutyrate in NaF-treated SH-SY5Y cells inhibited the expressions of autophagy markers, and decreased cell apoptosis. Taken together, these data suggest that neuronal death resulted from excessive ER stress and autophagic flux dysfunction contributes to fluoride-elicited neurotoxicity. Moreover, the autophagic flux dysfunction was mediated by excessive ER stress, which provided novel insight into a better understanding of fluoride-induced neurotoxicity.
اظهر المزيد [+] اقل [-]Bioindicators for monitoring marine litter ingestion and its impacts on Mediterranean biodiversity النص الكامل
2018
Fossi, Maria Cristina | Pedà, Cristina | Compa, Montserrat | Tsangaris, Catherine | Alomar, Carme | Claro, Francoise | Ioakeimidis, Christos | Galgani, François | Hema, Tatjana | Deudero, Salud | Romeo, Teresa | Battaglia, Pietro | Andaloro, Franco | Caliani, Ilaria | Casini, Silvia | Panti, Cristina | Baini, Matteo
Bioindicators for monitoring marine litter ingestion and its impacts on Mediterranean biodiversity النص الكامل
2018
Fossi, Maria Cristina | Pedà, Cristina | Compa, Montserrat | Tsangaris, Catherine | Alomar, Carme | Claro, Francoise | Ioakeimidis, Christos | Galgani, François | Hema, Tatjana | Deudero, Salud | Romeo, Teresa | Battaglia, Pietro | Andaloro, Franco | Caliani, Ilaria | Casini, Silvia | Panti, Cristina | Baini, Matteo
The Mediterranean Sea has been described as one of the most affected areas by marine litter in the world. Although effects on organisms from marine plastic litter ingestion have been investigated in several oceanic areas, there is still a lack of information from the Mediterranean Sea. The main objectives of this paper are to review current knowledge on the impact of marine litter on Mediterranean biodiversity, to define selection criteria for choosing marine organisms suitable for use as bioindicator species, and to propose a methodological approach to assessing the harm related to marine litter ingestion in several Mediterranean habitats and sub-regions. A new integrated monitoring tool that would provide the information necessary to design and implement future mitigation actions in the Mediterranean basin is proposed.According to bibliographic research and statistical analysis on current knowledge of marine litter ingestion, the area of the Mediterranean most studied, in terms of number of species and papers in the Mediterranean Sea is the western sub-area as well as demersal (32.9%) and pelagic (27.7%) amongst habitats.Applying ecological and biological criteria to the most threatened species obtained by statistical analysis, bioindicator species for different habitats and monitoring scale were selected. A threefold approach, simultaneously measuring the presence and effects of plastic, can provide the actual harm and sub-lethal effects to organisms caused by marine litter ingestion. The research revealed gaps in knowledge, and this paper suggests measures to close the gap. This and the selection of appropriate bioindicator species would represent a step forward for marine litter risk assessment, and the implementation of future actions and mitigation measures for specific Mediterranean areas, habitats and species affected by marine litter ingestion.
اظهر المزيد [+] اقل [-]Bioindicators for monitoring marine litter ingestion and its impacts on Mediterranean biodiversity النص الكامل
2018
Fossi, Maria Cristina | Pedà, Cristina | Compa, Montserrat | Tsangaris, Catherine | Alomar, Carme | Claro, Francoise | Ioakeimidis, Christos | Galgani, François | Hema, Tatjana | Deudero, Salud | Romeo, Teresa | Battaglia, Pietro | Andaloro, Franco | Caliani, Ilaria | Casini, Silvia | Panti, Cristina | Baini, Matteo | Deutsche Gesellschaft für Internationale Zusammenarbeit
The Mediterranean Sea has been described as one of the most affected areas by marine litter in the world. Although effects on organisms from marine plastic litter ingestion have been investigated in several oceanic areas, there is still a lack of information from the Mediterranean Sea. The main objectives of this paper are to review current knowledge on the impact of marine litter on Mediterranean biodiversity, to define selection criteria for choosing marine organisms suitable for use as bioindicator species, and to propose a methodological approach to assessing the harm related to marine litter ingestion in several Mediterranean habitats and sub-regions. A new integrated monitoring tool that would provide the information necessary to design and implement future mitigation actions in the Mediterranean basin is proposed. According to bibliographic research and statistical analysis on current knowledge of marine litter ingestion, the area of the Mediterranean most studied, in terms of number of species and papers in the Mediterranean Sea is the western sub-area as well as demersal (32.9%) and pelagic (27.7%) amongst habitats. Applying ecological and biological criteria to the most threatened species obtained by statistical analysis, bioindicator species for different habitats and monitoring scale were selected. A threefold approach, simultaneously measuring the presence and effects of plastic, can provide the actual harm and sub-lethal effects to organisms caused by marine litter ingestion. The research revealed gaps in knowledge, and this paper suggests measures to close the gap. This and the selection of appropriate bioindicator species would represent a step forward for marine litter risk assessment, and the implementation of future actions and mitigation measures for specific Mediterranean areas, habitats and species affected by marine litter ingestion | This work was supported by the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ), Grant number: 13.6257.3-002.00–81197130, within the Plastic Busters project-SDSN Solution Initiative. The authors would like to thank the Union for the Mediterranean and the UN Sustainable Development and Solution Network-Mediterranean that labelled and endorsed the project and the resulting paper. | Peer reviewed
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