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Removal of Per-, Poly-fluoroalkyl substances (PFASs) and multi-biosphere community dynamics in a bacteria-algae symbiotic aquatic ecosystem Texte intégral
2022
Wu, Jian-Yi | Gu, Li | Hua, Zu-Lin | Wang, Da-Wei | Xu, Run-Yang | Ge, Xin-Yue | Chu, Ke-Jian
The presence of Per-, Poly-fluoroalkyl substances (PFASs) in aquatic ecosystems has drawn broad concerns in the scientific community due to their biological toxicity. However, little has been explored regarding PFASs' removal in phytoplankton-dominated environments. This study aimed to create a simulated bacteria-algae symbiotic ecosystem to observe the potential transportation of PFASs. Mass distributions showed that sand (63–2000 μm), silt & clay (0–63 μm), the phycosphere (>3 μm plankton), and the free-living biosphere (0.22–3 μm plankton) contained 19.00, 7.78, 5.73 and 2.75% PFASs in their total mass, respectively. Significant correlations were observed between carbon chain lengths and removal rates (R² = 0.822, p < 10⁻⁴). Structural equation models revealed potential PFAS transportation pathways, such as water-phycosphere- free-living biosphere-sand-silt&clay, and water-sand-silt&clay (p < 0.05). The presence of PFASs decreased the bacterial density but increased algal density (p < 0.01) in the planktonic environment, and PFASs with longer carbon chain lengths showed a stronger enhancement in microbial community successions (p < 0.05). In algal metabolisms, chlorophyll-a and carotenoids were the key pigments that resisted reactive oxygen species caused by PFASs. PFBA (perfluorobutyric acid) (10.38–14.68%) and PFTeDA (perfluorotetradecanoic acid) (10.33–15.96%) affected bacterial metabolisms in phycosphere the most, while in the free-living biosphere was most effected by PFPeA (perfluorovaleric acid) (13.21–13.99%) and PFDoA (perfluorododecanoic acid) (10.04–10.50%). The results of this study provide new guidance measures for PFAS removal and management in aquatic environments.
Afficher plus [+] Moins [-]Associations of exposure to residential green space and neighborhood walkability with coronary atherosclerosis in Chinese adults Texte intégral
2022
Hu, Hai-Bo | Hou, Zhi-Hui | Huang, Cong-Hong | LaMonte, Michael J. | Wang, Meng | Lü, Bin
Residential green space and neighborhood walkability are important foundations of a healthy and sustainable city. Yet, their associations with atherosclerosis, the disease underlying clinical coronary heart disease (CHD), is unknown, especially in susceptible populations. We aim to explore the associations of exposure to residential green space and neighborhood walkability with coronary atherosclerosis. In this study of 2021 adults with suspected CHD, we evaluated the associations of exposure to green space (using Normalized Difference Vegetation Index [NDVI] and enhanced vegetation index [EVI] surrounding each participant's home) and neighborhood walkability (using walkability index and number of parks near home) with atherosclerosis (using coronary artery calcium score, CAC) using linear regression model adjusted for individual-level characteristics. Mediation analysis was further applied to explore potential mechanisms through the pathways of physical activity, air pollution, and psychological stress. In the primary model, an interquartile increase in annual mean NDVI and EVI within the 1-km area was associated with −15.8% (95%CI: 28.7%, −0.7%), and −18.6% (95%Cl: 31.3%, −3.6%) lower CAC score, respectively. However, an interquartile increase in the walkability index near home was associated with a 7.4% (95% CI: 0.1%, 15.2%) higher CAC score. The combined exposure to a green space area in a 1-km area and the walkability index were inversely associated with atherosclerosis, albeit with a smaller magnitude than a single-exposure model. The findings from a mediation analysis suggested that increased physical exercise and ameliorated particulate matter <2.5 μm (PM₂.₅) may partially contribute to the relationship between green space and atherosclerosis, and for walkability index, partially explained by increased PM₂.₅ exposure. Our study suggested a beneficial association between green space and atherosclerosis, but an adverse association between neighborhood walkability and atherosclerosis. Therefore, urban development that aims to improve neighborhood walkability should jointly account for enhancing green space properties from a public health perspective.
Afficher plus [+] Moins [-]Effect of CeO2 nanoparticles on plant growth and soil microcosm in a soil-plant interactive system Texte intégral
2022
Xie, Changjian | Guo, Zhiling | Zhang, Peng | Yang, Jie | Zhang, Junzhe | Ma, Yuhui | He, Xiao | Lynch, Iseult | Zhang, Zhiyong
The impact of CeO₂ nanoparticles (NPs) on plant physiology and soil microcosm and the underlying mechanism remains unclear to date. This study investigates the effect of CeO₂ NPs on plant growth and soil microbial communities in both the rhizosphere of cucumber seedlings and the surrounding bulk soil, with CeCl₃ as a comparison to identify the contribution of the particulate and ionic form to the phytotoxicity of CeO₂ NPs. The results show that Ce was significantly accumulated in the cucumber tissue after CeO₂ NPs exposure. In the roots, 5.3% of the accumulated Ce has transformed to Ce³⁺. This transformation might take place prior to uptake by the roots since 2.5% of CeO₂ NPs was found transformed in the rhizosphere soil. However, the transformation of CeO₂ NPs in the bulk soil was negligible, indicating the critical role of rhizosphere chemistry in the transformation. CeO₂ NPs treatment induced oxidative stress in the roots, but the biomass of the roots was significantly increased, although the Vitamin C (Vc) content and soluble sugar content were decreased and mineral nutrient contents were altered. The soil enzymatic activity and the microbial community in both rhizosphere and bulk soil samples were altered, with rhizosphere soil showing more prominent changes. CeCl₃ treatment induced similar effects although less than CeO₂ NPs, suggesting that Ce³⁺ released from CeO₂ NPs contributed to the CeO₂ NPs induced impacts on soil health and plant physiology.
Afficher plus [+] Moins [-]Treatment technologies for selenium contaminated water: A critical review Texte intégral
2022
Li, Tianxiao | Xu, Hongxia | Zhang, Yuxuan | Zhang, Hanshuo | Hu, Xin | Sun, Yuanyuan | Gu, Xueyuan | Luo, Jun | Zhou, Dongmei | Gao, Bin
Selenium is an indispensable trace element for humans and other organisms; however, excessive selenium in water can jeopardize the aquatic environment. Investigations on the biogeochemical cycle of selenium have shown that anthropogenic activities such as mining, refinery, and coal combustion mainly contribute to aquatic selenium pollution, imposing tremendous risks on ecosystems and human beings. Various technologies thus have been developed recently to treat selenium contaminated water to reduce its environmental impacts. This work provides a critical review on the applications, characteristics, and latest developments of current treatment technologies for selenium polluted water. It first outlines the present status of the characteristics, sources, and toxicity of selenium in water. Selenium treatment technologies are then classified into three categories: 1) physicochemical separation including membrane filtration, adsorption, coagulation/precipitation, 2) redox decontamination including chemical reduction and catalysis, and 3) biological transformation including microbial treatment and constructed wetland. Details of these methods including their overall efficiencies, applicability, advantages and drawbacks, and latest developments are systematically analyzed and compared. Although all these methods are promising in treating selenium in water, further studies are still needed to develop sustainable strategies based on existing and new technologies. Perspectives on future research directions are laid out at the end.
Afficher plus [+] Moins [-]The variations of antibiotics and antibiotic resistance genes in two subtropical large river basins of south China: Anthropogenic impacts and environmental risks Texte intégral
2022
Gao, Fang-Zhou | He, Liang-Ying | Hu, Li-Xin | Chen, Jun | Yang, Yuan-Yuan | He, Lu-Xi | Bai, Hong | Liu, You-Sheng | Zhao, Jian-Liang | Ying, Guang-Guo
Emission of antibiotics into riverine environments affects aquatic ecosystem functions and leads to the development of antibiotic resistance. Here, the profiles of forty-four antibiotics and eighteen antibiotic resistance genes (ARGs) were analyzed in two large rivers of the Pearl River System. In addition, the risks of ecotoxicity and resistance selection posed by the antibiotics were estimated. As compared to the reservoirs, the river sections close to the urban and livestock areas contained more antibiotics and ARGs. Seasonal variations of antibiotics (higher in the dry season) and relative ARGs (normalized by 16S rRNA gene, higher in the wet season) were found in the water, but not in the sediment. Sulfonamide resistance genes were the most prevalent ARGs in both river water and sediment. Antibiotic concentration was correlated with ARG abundance in the water, indicating that antibiotics play a critical role in ARG spread. In addition, oxytetracycline was the most abundant antibiotic with concentrations up to 2030 ng/L in the water and 2100 ng/g in the sediment respectively, and posed the highest risks for resistance selection. Oxytetracycline, tetracycline and sulfamethoxazole were expected to be more ecotoxicologically harmful to aquatic organisms, while ofloxacin, enrofloxacin, norfloxacin, chlortetracycline, oxytetracycline and tetracycline posed ecotoxicological risks in the sediment. The Nanliujiang river with intensive livestock activities was contaminated by antibiotics and ARGs and faced high ecotoxicological and resistance selection risks. Collectively, these findings reflect the impacts of anthropogenic activities on the spread of antibiotic resistance in large river basins.
Afficher plus [+] Moins [-]Mitigation effects of exogenous melatonin-selenium nanoparticles on arsenic-induced stress in Brassica napus Texte intégral
2022
Farooq, Muhammad Ahsan | Islam, Faisal | Ayyaz, Ahsan | Chen, Weiqi | Noor, Yamna | Hu, Weizhen | Hannan, Fakhir | Zhou, Weijun
Melatonin (MT) and selenium (Se) application known to decrease heavy metal uptake and toxicity in plants. By mixing the Se in MT medium a new complex MT-Se nanoparticles (MT-Se NPs) was synthesized and we investigated the role of MT-Se NPs on B. napus growth and tolerance against As stress. The MT-Se particles significantly enhanced the plant growth and other associated physiological attributes under As stress. The As treatment at 80 μM was more phytotoxic, however MT-Se NPs application resulted in a substantial increase in leaf chlorophyll fluorescence, biomass accumulation, and decreased ROS relative to As stressed plants. The use of MT-Se NPs to As stressed plants reduced photosynthetic inhibition and oxidative stress and attenuated the increase in MDA and H₂O₂ contents. The application of MT-Se NPs also boosted the antioxidant enzymes activities such as SOD, POD and CAT as well as the APX, GR and GSH activates under As stress. The results also showed MT-Se NPs treatments alleviated the growth inhibition induced by As and reduced the accumulation of As in leaves and roots of B. napus seedlings. Moreover, treatment with MT-Se NPs improved the plant growth more successfully than treatment of MT and Se alone. This study explored the mechanism of melatonin and selenium efficiency in the composition can be jointly encouraged to exert synergistic effects and boost plant enzymatic activities.
Afficher plus [+] Moins [-]Dietary exposure to environmentally relevant pesticide mixtures impairs swimming performance and lipid homeostatic gene expression in Juvenile Chinook salmon at elevated water temperatures Texte intégral
2022
Fuller, Neil | Magnuson, Jason T. | Huff Hartz, Kara E. | Whitledge, Gregory W. | Acuña, Shawn | McGruer, Victoria | Schlenk, Daniel | Lydy, Michael J.
Aquatic organisms are exposed to complex mixtures of pesticides in the environment, but traditional risk assessment approaches typically only consider individual compounds. In conjunction with exposure to pesticide mixtures, global climate change is anticipated to alter thermal regimes of waterways, leading to potential co-exposure of biota to elevated temperatures and contaminants. Furthermore, most studies utilize aqueous exposures, whereas the dietary route of exposure may be more important for fish owing to the hydrophobicity of many pesticides. Consequently, the current study aimed to determine the effects of elevated temperatures and dietary pesticide mixtures on swimming performance and lipid metabolism of juvenile Chinook salmon, Oncorhynchus tshawytscha. Fish were fed pesticide-dosed pellets at three concentrations and three temperatures (11, 14 and 17 °C) for 14 days and swimming performance (Uₘₐₓ) and expression of genes involved in lipid metabolism and energetics were assessed (ATP citrate lyase, fatty acid synthase, farnesoid x receptor and liver x receptor). The low-pesticide pellet treatment contained five pesticides, p,p’-DDE, bifenthrin, esfenvalerate, chlorpyrifos and fipronil at concentrations based on prey items collected from the Sacramento River (CA, USA) watershed, with the high-pesticide pellet treatment containing a six times higher dose. Temperature exacerbated effects of pesticide exposure on swimming performance, with significant reductions in Uₘₐₓ of 31 and 23% in the low and high-pesticide pellet groups relative to controls at 17 °C, but no significant differences in Uₘₐₓ among pesticide concentrations at 11 or 14 °C. At 14 °C there was a significant positive relationship between juvenile Chinook salmon pesticide body residues and expression of ATP citrate lyase and fatty acid synthase, but an inverse relationship and significant downregulation at 17 °C. These findings suggest that temperature may modulate effects of environmentally relevant pesticide exposure on salmon, and that pesticide-induced impairment of swimming performance may be exacerbated under future climate scenarios.
Afficher plus [+] Moins [-]Integration of biochar into Ag3PO4/α-Fe2O3 heterojunction for enhanced reactive oxygen species generation towards organic pollutants removal Texte intégral
2022
Qian, Yifan | Shi, Jun | Yang, Xianni | Yuan, Yangfan | Liu, Li | Zhou, Ganghua | Yi, Jianjian | Wang, Xiaozhi | Wang, Shengsen
A biochar (BC) harbored Ag₃PO₄/α-Fe₂O₃ type-Ⅰ heterojunction (Ag-Fe-BC) was prepared by a hydrothermal-impregnation method to transfer active center of heterojunctions. The electrochemical and spectroscopic tests demonstrated that BC enhanced the catalytic performance of the heterojunction by enhancing photocurrent, reducing fluorescence intensity, and facilitating separation of electron-hole pairs. The photocatalytic activity showed the Ag-Fe-BC (5:1:3) could degrade Rhodamine B (20 mg/L) by up to 92.7%, which was 3.35 times higher than Ag₃PO₄/α-Fe₂O₃. Tetracycline and ciprofloxacin (20 mg/L) were degraded efficiently by 58.3% and 79.4% within 2 h, respectively. Electron paramagnetic resonance and scavenging experiments confirmed the major reactive oxygen species (ROS) consisted of singlet oxygen (¹O₂) and superoxide (·O₂⁻). Excellent RhB adsorption and electrons capturing capacity of BC facilitated electron-hole pairs separation and ROS transferring to target organics followed by elevated degradation. Thus, a facile method was proposed to synthesize a highly efficient visible-light responsive photocatalyst for degradation of various organics in water.
Afficher plus [+] Moins [-]Multigenerational inspections of environmental thermal perturbations promote metabolic trade-offs in developmental stages of tropical fish Texte intégral
2022
Wang, Min-Chen | Furukawa, Fumiya | Wang, Jingwei | Peng, Hui-Wen | Lin, Ching-Chun | Lin, Tzu-Hao | Tseng, Yung-Che
Global warming both reduces global temperature variance and increases the frequency of extreme weather events. In response to these ambient perturbations, animals may be subject to trans- or intra-generational phenotype modifications that help to maintain homeostasis and fitness. Here, we show how temperature-associated transgenerational plasticity in tilapia affects metabolic trade-offs during developmental stages under a global warming scenario. Tropical tilapia reared at a stable temperature of 27 °C for a decade were divided into two temperature-experience groups for four generations of breeding. Each generation of one group was exposed to a single 15 °C cold-shock experience during its lifetime (cold-experienced CE group), and the other group was kept stably at 27 °C throughout their lifetimes (cold-naïve CN group). The offspring at early life stages from the CE and CN tilapia were then assessed by metabolomics-based profiling, and the results implied that parental cold-experience might affect energy provision during reproduction. Furthermore, at early life stages, progeny may be endowed with metabolic traits that help the animals cope with ambient temperature perturbations. This study also applied the feature rescaling and Uniform Manifold Approximation and Projection (UMAP) to visualize metabolic dynamics, and the result could effectively decompose the complex omic-based datasets to represent the energy trade-off variability. For example, the carbohydrate to free amino acid conversion and enhanced compensatory features appeared to be hypothermic-responsive traits. These multigenerational metabolic effects suggest that the tropical ectothermic tilapia may exhibit transgenerational phenotype plasticity, which could optimize energy allocation under ambient temperature challenges. Knowledge about such metabolism-related transgenerational plasticity effects in ectothermic aquatic species may allow us to better predict how adaptive mechanisms will affect fish populations in a climate with narrow temperature variation and frequent extreme weather events.
Afficher plus [+] Moins [-]Methyltransferase-like 3 leads to lung injury by up-regulation of interleukin 24 through N6-methyladenosine-dependent mRNA stability and translation efficiency in mice exposed to fine particulate matter 2.5 Texte intégral
2022
He, Xiang | Zhang, Lei | Liu, Shengbin | Wang, Junyi | Liu, Yao | Xiong, Anying | Jiang, Manling | Luo, Li | Ying, Xiong | Li, Guoping
Fine particulate matter 2.5 (PM2.5) exposure leads to the progress of pulmonary disease. It has been reported that N6-methyladenosine (m6A) modification was involved in various biological processes and diseases. However, the critical role of m6A modification in pulmonary disease during PM2.5 exposure remains elusive. Here, we revealed that lung inflammation and mucus production caused by PM2.5 were associated with m6A modification. Both in vivo and in vitro assays demonstrated that PM2.5 exposure elevated the total level of m6A modification as well as the methyltransferase like 3 (METTL3) expression. Integration analysis of m6A RNA immunoprecipitation-seq (meRIP-seq) and RNA-seq discovered that METTL3 up-regulated the expression level and the m6A modification of Interleukin 24 (IL24). Importantly, we explored that the stability of IL24 mRNA was enhanced due to the increased m6A modification. Moreover, the data from qRT-PCR showed that PM2.5 also increased YTH N6-Methyladenosine RNA Binding Protein 1 (YTHDF1) expression, and the up-regulated YTHDF1 augmented IL24 mRNA translation efficiency. Down-regulation of Mettl3 reduced Il24 expression and ameliorated the pulmonary inflammation and mucus secretion in mice exposed to PM2.5. Taken together, our finding provided a comprehensive insight for revealing the significant role of m6A regulators in the lung injury via METTL3/YTHDF1-coupled epitranscriptomal regulation of IL24.
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