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In vitro profiling of endocrine disrupting potency of 2,2′,4,4′-tetrabromodiphenyl ether (BDE47) and related hydroxylated analogs (HO-PBDEs) Full text
2011
Liu, Hongling | Hu, Wei | Sun, Hong | Shen, Ouxi | Wang, Xinru | Lam, Michael H.W. | Giesy, John P. | Zhang, Xiaowei | Yu, Hongxia
The potential of 2,2′,4,4′-tetrabromodiphenyl ether (BDE47) and its related hydroxylated analogs (2′-HO-BDE28, 6-HO-BDE47, 4′-HO-BDE17, and 4′-HO-BDE49) to modulate estrogen/thyroid/androgen receptor-(ER, TR, AR), mediated responses were investigated by use of reporter gene assays. Exposure to 1 or 10μM, 4′-HO-BDE17 significantly up-regulated expression of Luc, whereas other four chemicals did not induce Luc expression under control of the ER. Anti-estrogenic potency was observed for 4′-HO-BDE17 (IC50=1.14μM)>6-HO-BDE47 (IC50=2.65μM)>2′-HO-BDE28 (IC50=9.49μM)>BDE47 (IC50=21.11μM). No anti-estrogenic effect of 4′-HO-BDE49 was observed. Both 4′-HO-BDE17, 4′-HO-BDE49 resulted in greater responses of Luc expression induced by T3. BDE47, 2′-HO-BDE28, 6-HO-BDE47 did not show any effect on the expression of Luc induced by 5nM T3. 6-HO-BDE47 (IC50=0.34μM)>4′-HO-BDE17 (IC50=1.41μM)>BDE47 (IC50=3.83μM)>2′-HO-BDE28 (IC50=29.22μM) exhibited anti-androgenic potency, while 4′-HO-BDE49 did not show androgenic transcriptional activity.
Show more [+] Less [-]The use of plastic debris as nesting material by a colonial seabird and associated entanglement mortality Full text
2011
Votier, Stephen C. | Archibald, Kirsten | Morgan, Greg | Morgan, Lisa
Entanglement with plastic debris is a major cause of mortality in marine taxa, but the population-level consequences are unknown. Some seabirds collect marine debris for nesting material, which may lead to entanglement. Here we investigate the use of plastics as nesting material by northern gannets Morus bassanus and assess the associated levels of mortality. On average gannet nests contained 469.91g (range 0–1293g) of plastic, equating to an estimated colony total of 18.46 tonnes (range 4.47–42.34tonnes). The majority of nesting material was synthetic rope, which appears to be used preferentially. On average 62.85±26.84 (range minima 33–109) birds were entangled each year, totalling 525 individuals over eight years, the majority of which were nestlings. Although mortality rates are high, they are unlikely to have population-level effects. The use of synthetic fibres as nesting material is a common strategy among seabirds, but the impacts of entanglement warrants further investigation.
Show more [+] Less [-]Environmental capacity of nitrogen and phosphorus pollutions in Jiaozhou Bay, China: Modeling and assessing Full text
2011
Han, Hongyan | Li, Keqiang | Wang, Xiulin | Shi, Xiaoyong | Qiao, Xudong | Liu, Jing
In recent years, with the development of society and economy of Qingdao, environment and ecosystem problems, for instance, red ties, become more and more serious in Jiaozhou Bay, China, because of the increasing pollutants discharged into it. In order to solve these problems, an eco-hydrodynamic model is constructed to estimate the marine environmental capacity of nitrogen and phosphorus nutrients in Jiaozhou Bay, whose simulation results are rational for the bay. According to the model, if the target is set to achieve water quality (grade II) in Jiaozhou Bay, the environmental capacity of dissolved inorganic nitrogen and phosphorus in one year are approximately 7800 and 840tons, respectively. Thus our research offers necessary scientific foundation to the total loads control efforts in this area.
Show more [+] Less [-]The marine medaka Oryzias melastigma – A potential marine fish model for innate immune study Full text
2011
Bo, Jun | Cai, Ling | Xu, Jia-He | Wang, Ke-Jian | Au, Doris W.T.
The objective of this study is to develop the marine medaka Oryzias melastigma as a potential marine fish model for innate immune and immunotoxicological studies. Hepcidin plays an important role in innate immune system. Two hepcidin genes (OM-hep1 and OM-hep2) were identified and characterized in the O. melastigma, which were highly conserved with other reported hepcidins. During embryogenesis, significant elevation of OM-hep1 and OM-hep2 transcripts were coincided with liver development in the embryos. In adult medaka, differential tissue expressions of both hepcidin transcripts were evident: high in liver, moderate in spleen and low in non-immune tissues. After bacterial challenge, the two hepcidin mRNAs were rapidly and remarkably induced in liver and spleen, suggesting the two OM-hepcidins in O. melastigma play a complementary role in innate defense. Gender difference in time of induction and extent of the two hepcidin mRNAs elevation in infected O. melastigma should be considered in immunotoxicological studies.
Show more [+] Less [-]Isolation, characterization of Rhodococcus sp. P14 capable of degrading high-molecular-weight polycyclic aromatic hydrocarbons and aliphatic hydrocarbons Full text
2011
Song, Xiaohui | Xu, Yan | Li, Gangmin | Zhang, Ying | Huang, Tongwang | Hu, Zhong
Rhodococcus sp. P14 was isolated from crude oil-contaminated sediments. This strain was capable of utilizing three to five rings polycyclic aromatic hydrocarbons (PAHs) including phenanthrene (Phe), pyrene (Pyr), and benzo[a]pyrene (BaP) as a sole carbon and energy source. After cultivated with 50mg/L of each PAH, strain P14 removed 43% Phe, 34% Pyr and 30% BaP in 30 d. Four different hydroxyphenanthrene products derived from Phe by strain P14 (1,2,3,4-hydroxyphenanthrene) were detected using SPME–GC–MS. Strain P14 also was capable of degrading mineral oil with n-alkanes of C17 to C21 carbon chain length. Compared with glucose-grown cells, PAHs-grown cells had decreased contents of shorter-chain length fatty acids (⩽C16:0), increased contents of C18:0, Me-C19:0 and disappeared odd-number carbon chain fatty acids. The contents of unsaturated C19:1, Me-C19:0 increased and C18:0 decreased in mineral oil-grown cells. At the same time, the strain P14 tended to float when cultivated in mineral oil-supplemented liquid medium. The degradation capability of P14 to alkane and PAHs and its floating characteristics will be very helpful for future’s application in oil-spill bioremediation.
Show more [+] Less [-]Differences in leaf construction cost between alien and native mangrove species in Futian, Shenzhen, China: Implications for invasiveness of alien species Full text
2011
Li, Fenglan | Yang, Qiong | Zan, Qijie | Tam, Nora F.Y. | Shin, Paul K.S. | Vrijmoed, Lilian L.P. | Cheung, S.G.
Construction cost (CC) is a quantifiable measure of energy demand for biomass production, and low CC is hypothesized to give an alien plant growth advantages and increase its potential to be an invader. Comparison of leaf CC and growth traits between alien and native mangroves in Shenzhen Futian Nature Reserve showed CC per unit mass (CCₘₐₛₛ), carbon concentration and gross and ash-free caloric values of alien mangroves were significantly lower than those of native species, while the height and chest circumference were just the opposite. Alien species Sonneratia apetala had the lowest CCₘₐₛₛ while Sonneratia caseolaris had the lowest CCₐᵣₑₐ, and were 8.99% and 32.17% lower than those of native species, respectively. Conversely, specific leaf area (SLA) of these two Sonneratia species was significantly higher than native species. Lower CC and higher SLA make the two Sonneratia species grow and spread faster than other mangroves and enhance their invasive potential.
Show more [+] Less [-]The atmospheric lead record preserved in lagoon sediments at a remote equatorial Pacific location: Palmyra Atoll, northern Line Islands Full text
2011
Collen, John D. | Baker, Joel A. | Dunbar, Robert B. | Rieser, Uwe | Gardner, Jonathan P. | Garton, David W. | Christiansen, Kylie J.
Anthropogenic lead (Pb) inputs to the atmosphere increased greatly over the past century and now dominate Pb supply to the oceans. However, the Pb content of sediments across the equatorial Pacific region is relatively unknown, and data exist only for deep sea sites where Pb deposition lags surface water inputs by up to a century. Here we present ICP-MS analyses of Pb of a core from a lagoon at Palmyra Atoll, northern Line Islands, that spans approximately the past 160years. The non-bioturbated sediments of the euxinic lagoon, coupled with rapid rates of deposition, provide a unique fine-scale record of atmospheric Pb supply at a remote Pacific location. These first observations of historic Pb sedimentation in an atoll lagoon reveal a 63-fold increase in Pb flux to sediments during the past century and correlate directly with the North American consumption of leaded gasoline that began in 1926.
Show more [+] Less [-]Fast and easy method for seagrass monitoring: Application of acoustic telemetry to precision mapping of Posidonia oceanica beds Full text
2011
Descamp, Pierre | Holon, Florian | Ballesta, Laurent | Guilbert, Antonin | Guillot, Marie | Boissery, Pierre | Raimondino, Valérie | Deter, Julie
Posidonia oceanica is an endemic seagrass from the Mediterranean Sea. It is an indicator of water quality and of the ecological state of coastal ecosystems. The aim of this paper is to test acoustic telemetry for monitoring the position of P. oceanica meadow limits with varied types. After evaluating the accuracy of the system, we present results from a spatiotemporal survey of P. oceanica meadows on nine sites located on the French coast. The method has been demonstrated to be highly efficient for high precision underwater mapping regardless of meadow type, with 1cm accuracy for a distance of 40m between the base and the pointer. A temporal survey led at Cerbere–Banyuls shows a weak global progression of 4m² (progression of 26m² - regression of 22m²) between 2006 and 2010. Finally, we discuss the cost and efficiency of this method, and wether it should be generalized for further studies.
Show more [+] Less [-]Assessment of heavy metal contamination and mineral magnetic characterization of the Asopos River sediments (Central Greece) Full text
2011
Botsou, F. | Karageorgis, A.P. | Dassenakis, E. | Scoullos, M.
The content and distribution of heavy metals in sediments of the intermittent and contaminated Asopos River, located in Central Greece, was assessed by means of total dissolution, dilute acid and sequential extraction procedures. Mineral magnetic properties were used as proxy parameters of transport mechanisms of land-derived material to the sea. The combination of enrichment factors estimated against local background levels and the levels of labile metals revealed that surface sediments are enriched in Cu, Cd, Ni and Cr. The low flow of the system allows particles and organic matter to accumulate in the estuarine shallow “pools” where they undertake a series of redox reactions, authigenic formation, etc. The most fine of these particles, which are metal rich, are transported to relatively long distances off the Asopos River mouth, even under low energy conditions, converting the system to a secondary source of pollution for the adjacent marine environment.
Show more [+] Less [-]Nutrient sources and composition of recent algal blooms and eutrophication in the northern Jiulong River, Southeast China Full text
2011
Li, Ying | Cao, Wenzhi | Su, Caixia | Hong, Huasheng
The natural process of eutrophication is accelerated by human activities worldwide that interrupt nutrient biogeochemical cycles. Three algal bloom events have been monitored in the northern tributary of the Jiulong River since 2009. The inflection points in a robust locally-weighted regression analysis (LOESS) of the relationship between TN and TP concentrations in the river water, and a TN:TP comparison with nutrient source loadings, suggested that both external loading and internal nutrient cycling contributed to these algal blooms. Nutrient release from the sediments may have played an important role in regulating the nutrients in the overlying water column. In particular, excessive nutrient inputs from various sources and ubiquitous river damming caused further accumulation of the nutrient loading. In-situ autochthonous primary production was enhanced in this relatively stable “river” to “lake” water body. Thus, attention must be paid to the effects of river damming and the consequent internal nutrient release.
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