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Color vision, initiated from cone cells, is vitally essential for identifying environmental information in vertebrate. Although the retinotoxicity of bisphenol S (BPS) has been reported, data on the influence of BPS treatment on cone cells are scarce. In the present study, transgenic zebrafish (Danio rerio) labeling red and ultraviolet (UV) cones were exposed to BPS (0, 1, 10, and 100 μg/L) during the early stages of retinal development, to elucidate the mechanism underlying its retinal cone toxicity of BPS. The results showed that 10 and 100 μg/L BPS induced oxidative DNA damage, structural damage (decreased number of ribbon synapses), mosaic patterning disorder, and altered expression of genes involved in the phototransduction pathway in red and UV cones. Furthermore, BPS exposure also caused abnormal development of key neurons (retinal ganglion cells, optic nerve, and hypothalamus), responsible for transmitting the light-electrical signal to brain, and thereby resulted in inhibition of light-electrical signal transduction, finally diminishing the spectral sensitivity of zebrafish larvae to long- and short-type light signal at 5 day post fertilization. This study highlights the cone-toxicity of environmental relevant concentrations of BPS, and clarifies the mechanism of color vision impairment induced by BPS at the cellular level, updating the understanding of visual behavior driven by environmental factors.

A risk assessment for storm surge disasters can provide scientific support for coastal management as well as marine disaster prevention and mitigation. By taking the Wenchang City of Hainan Province as a pilot area, a risk assessment approach for typhoon-induced storm surge disasters is introduced in detail in this article. First, a numerical simulation system for storm surge inundation is developed, which is applied for the simulation and calculation of the probable maximum storm surge in Wenchang, and the obtained inundation areas and depths are used to assess the storm surge hazard. Then, the data of land use and disaster-bearing bodies are used to classify and assess the vulnerability of Wenchang. Finally, by taking the community as unit, the risk assessment for typhoon-induced storm surge affecting Wenchang is performed by combining the assessment results of both hazard and vulnerability, thereby obtaining a level map of risk distribution. The results show that there are risks of typhoon-induced storm surge in most of the coastal areas of Wenchang, especially for its northeast and east coastal areas, where the risks reach Levels I–II. This approach can be conveniently applied to risk assessments of storm surge in other coastal areas. Note that this approach focuses on the current risk of typhoon-induced storm surge in coastal areas, and further studies will be conducted on the assessment methods for the potential risk.

Bisphenol S (BPS) is extensively used in "bisphenol A-free" products such as baby bottles. Although the visual toxicity of BPS has been reported, the underlying mechanism was largely unknown. In the present study, zebrafish were exposed to 0, 4 and 400 nM BPS from 2 h post-fertilization (hpf) to 120 hpf to further explore the thyroid disruption mechanism underlying the BPS induced impairment of visual function. The results showed that BPS decreased T3 levels in larval eyes, induced retinal expression of thyroid hormone receptor β (TRβ), and thereby down-regulated the expression of TH-mediated opsin genes (opn1lw1, opn1lw2, opn1mw1, opn1mw2, opn1mw3, and opn1sw2) and impaired subsequent phototransduction pathways, leading to decreased visually mediated phototactic response and body color adaptation but stimulated visual motor response (VMR). Combining exposure of exogenous T3 or 1-850 (antagonist for TRβ) with BPS could partly compensate the inhibited expression of opsin genes (opn1mw2, opn1lw1, and opn1lw2) and alleviate the hyperactivity of larval VMR caused by BPS alone, suggesting that BPS disrupted the opsins expression and also light-sensing function via antagonizing TH-TRβ signaling pathway. This study underlined the importance of TH signaling in regulating the proper vision and proposed a novel mechanism for the visual toxicity of BPS.

Anaerobic ammonium oxidation (anammox) process was found to make a nonnegligible contribution to nitrogen loss in estuarine and coastal ecosystems in recent years. In order to better understand ecological characteristics of anammox bacteria in coastal ecosystems, 16S rRNA gene clone library and real-time quantitative PCR (qPCR) were used to investigate the diversity and abundance of anammox bacteria in sediments of the Dongzhai Harbor mangrove wetland in Hainan, China. Sediments at different depths along a transect from mangrove trees to mudflats were studied in March (spring) and August (summer). The dominant genera of anammox bacteria observed in both seasons were Kuenenia spp. and Scalindua spp. The diversity and abundance of anammox bacteria showed not only seasonal variations, but also differences with depths and habitats. Anammox bacteria appeared to be more abundant and had higher diversity in August than in March. In addition, lower layer (40–45 cm) sediments and mangrove sediments had higher abundance and diversity of anammox bacteria than surface layers (0–2 cm) and non-mangrove areas. It was suggested that water pH, salinity and sediment nitrite, nitrate and ammonium might be key factors shaping the community structure and distribution of anammox bacteria. This study further indicated that the mangrove ecosystem might provide a favorable niche for anammox bacteria and thus plays an important role in nitrogen cycling. Overall, these results extend our current knowledge about the structure and dynamics of anammox bacterial community in the mangrove ecosystem.

The conditions to extract alchol soluble proteins of leaves of Wedelia trilobata (L.) Hitchc. were discussed. When the extractant was alcohol, the weight of leave(g) -to- volume of 75% alcohol solution (mL) ratio was 1:10, temperature for extraction was 50°Cand the extraction period was 2hrs, the concentration of alcohol solution needed for the best extraction effect was 95% (V/V). When the extractant was 75% alcohol solution, the temperature for extraction was 50°Cand the extraction period was 2hrs, the weight of leave(g) -to- volume of 75% alcohol solution (mL) ratio needed for the best extraction effect was 1:20. When the extractant was 75% alcohol solution, the weight of leave(g) -to- volume of 75% alcohol solution (mL) ratio was 1:10 and the extraction period was 2 hrs, the temperature needed for the best extraction effect was 55°C. When the extractant was 75% alcohol solution, the weight of leave(g) -to- volume of 75% alcohol solution (mL) ratio was 1:10 and the temperature for extraction was 50°C, the extraction period needed for the best extraction effect was 2hrs.

The green mussel Perna viridis is an ideal biomonitor to evaluate marine environmental pollution. Benzo(a)pyrene (BaP) is a typical polycyclic aromatic hydrocarbon (PAH), which is well known for the mutagenic and carcinogenic characteristics. However, the toxicological effects of BaP on Perna viridis embryo are still unclear. In this study, we investigated the embryo transcriptomic profile of Perna viridis treated with BaP via digital gene expression analysis. A total of 92,362,742 reads were produced from two groups (control and BaP exposure) by whole transcriptome sequencing (RNA-Seq). Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis were used on all genes to determine the biological functions and processes. Genes involved in various molecular pathways of toxicological effects were enriched further. The differential expression genes (DEGs) were related to stress response, infectious disease and innate immunity. Quantitative real-time PCR (qRT-PCR) measured expressional levels of six genes confirmed through the DGE analysis. This study reveals that RNA-seq for transcriptome profiling of P. viridis embryo can better understand the embryo toxic effects of BaP. Furthermore, it also suggests that RNA-seq is a superior tool for generating novel and valuable information for revealing the toxic effects caused by BaP at transcriptional level.

Litopenaeus vannamei has a high commercial value and is the primary cultured shellfish species globally. In this study, we have compared the hemolymph physiological responses between two L. vannamei strains under acute hypoxia. The results showed that hemocyanin concentration (HC) of strain A6410 was significantly higher than strain Zhengda; Total hemocyte counts (THC) decreased significantly in both strains under hypoxic stress (p0.05). We also investigated the temporal and spatial variations of hypoxia inducible factors 1 (HIF-1) by qRT-PCR. The results showed that hypoxia for 12 h increased the expression levels of HIF-1α in tissues of muscle and gill from the two strains (p0.05). In the hepatopancreas, the expression levels of HIF-1 increased significantly in strain Zhengda and decreased significantly in strain A6410 (p0.05). No significant changes of HIF-1 expression were detected in the same tissues between the two strains under hypoxia for 6 h (p0.05), but in the gills and hepatopancreas under hypoxia for 12 h (p0.05). Additionally, the expression level of HIF-1 was higher in the strain Zhengda than A6410 in the same tissue under hypoxia for 12 h. It was indicated that the hypoxic tolerance of Litopenaeus vannamei was closely correlated with the expression level of HIF-1, and the higher expression level of HIF-1 to hypoxia, the lower tolerance to hypoxia in the early stage of hypoxia. These results can help to better understand the molecular mechanisms of hypoxic tolerance and speed up the selective breeding process of hypoxia tolerance in L. vannamei.

To evaluate the genotoxic and physiological effects of acute hypoxia on the pacific white shrimp (L. vannamei), shrimps were treated firstly with three dissolved oxygen levels 6.5 ppm (control), 3.0 ppm and 1.5 ppm for 24 h, respectively, and then reoxygenated (6.5 ppm) for 24 h. The changes of superoxide dismutase (SOD) activity, glutathione peroxidases (GPX) activity, malondialdehyde (MDA) concentration and DNA damage in the tissues of gill, hepatopancreas and hemolymph were examined during the period of hypoxia and reoxygenation. The results indicated SOD activity, GPX activity, MDA concentration and DNA damage all increased basically compared with the control during the period of hypoxia except for MDA concentrations in the gill at 12 h and 24 h hypoxia (3.0 ppm), and these parameters were recovered to some degree during the period of reoxygenation. Moreover, the comet assays in the tissues of gill and hepatopancreas showed an obvious time- and dose-dependent response to hypoxia, which indicated comet assay in the two tissues could be used as sensitive biomarker to detect the occurrence of hypoxia. We conclude that acute hypoxia can induce oxidative stress, DNA damage and lipid peroxidation in the tissues of gill, hepatopancreas and hemolymph of L. vannamei and the DNA damage may come from hypoxia-induced oxidative stress.

Perna viridis is an ideal marine pollution bioindicator, benzo(a)pyrene (BaP) and 2,4′-dichlorodiphenyltrichloroethane (2,4′-DDT) are estrogenic and ubiquitous in marine environments. The toxic effects of a mixture of pollutants are more complicated. A global view of the protein and metabolite responses to single EEs compared to their mixture offers another dimension for revealing the toxic effects of EEs on marine animals. The objective of this study was to investigate the different proteomic and metabolomic responses in the female gonad of the green mussel P. viridis exposed to BaP, 2,4′-DDT and their mixture. Here we have applied NMR spectroscopy-based metabolomics and two-dimensional gel electrophoresis mass spectrometry-based proteomics to elucidate the protein and metabolite responses of female green mussel gonad exposed to BaP, 2,4′-DDT and their mixture. The statistical analysis methods including partial least squares discriminant analysis and orthogonal projection to the latent structure with discriminant analysis were used for data classification. Proteomic responses revealed that 2,4′-DDT and its mixture with BaP showed more severe disturbances in energy metabolism, cell structure and oxidative defense compared to BaP treatment alone. The results of the metabolic responses demonstrated that both 2,4′-DDT and its mixture with BaP mainly induced disturbances in energy metabolism and osmotic regulation. In contrast to what was found with the 2,4′-DDT treatment alone, the mixture of BaP and 2,4′-DDT mainly depressed taurine metabolism by lowering the expression of its metabolite, arginine. Furthermore, the differentially expressed proteins, pancreatic triacylglycerol lipase and the pyruvate dehydrogenase E1 component subunit beta, were confirmed by their related metabolic biomarkers, including ATP and acetoacetate. Our results provide an insight into the metabolic responses of mussel P. viridis exposed to either BaP, 2,4′-DDT or their mixture and characterize some potential biomarkers that were identified by a combined metabolomic and proteomic approach.

Benzo(a)pyrene and dichlorodiphenyltrichloroethane are typical persistent organic pollutants, and also the widespread environmental estrogens with known toxicity towards green mussels Perna viridis. In this study, the toxicological effects of BaP and DDT and their mixture were assessed in green mussel gonads using proteomic and metabolomic approaches. Metabolomics by NMR spectroscopy revealed that BaP did not show obvious metabolite changes in the gonad of male green mussel. DDT mainly caused some disturbance of osmotic regulation and energy metabolism by changing BCAAs, alanine, threonine, arginine, etc., unknown metabolite (3.53 ppm), glycine, homarine and ATP at different levels. However, the mixture of BaP and DDT mainly caused some disturbance in osmotic regulation and energy metabolism by differentially altering branched chain amino acids, glutamate, alanine, arginine, unknown metabolite (3.53 ppm), glycine, 4-aminobutyrate, dimethylglycine, homarine and ATP. The results suggest that DDT alone may cause most of metabolites changes in the mixture exposed male mussel gonad, and the results also show that the male P. viridis gonad was more sensitive to DDT than BaP exposures. Proteomic study showed that BaP, DDT and their mixture may have different modes of action. Proteomic responses revealed that BaP induced signal transduction, oxidative stress, spermatogenesis, etc. in the male green mussel gonad; whereas DDT exposure altered proteins that were associated with signal transduction, oxidative stress, cytoskeleton and cell structure, cellular organization, energy metabolism, etc. However, the mixture of BaP and DDT affected proteins related to cytoskeleton and cell structure, oxidative stress, cellular organization, etc. This research demonstrated that metabolomic and proteomic approaches could better elucidate the underlying mechanism of environmental pollutants gonad toxicity.