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miR398 is involved in the relief of phenanthrene-induced oxidative toxicity in wheat roots 全文
2020
Li, Jinfeng | Shen, Yu | Zhu, Jiahui | Liu, Shiqi | Zeng, Nengde | Zhan, Xinhua
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants and could produce oxidative toxicity to plants. Our previous study has shown that miR398 is involved in response to phenanthrene treatment by targeting CSD1 and CSD2. However, it is not clear which is essential for CSD1 and CSD2 and how miR398 changes. In this study, we performed discontinuous PAGE to separate superoxide dismutase (SOD) isozymes and found that two bands of the cytosolic Cu/Zn-SOD are induced by phenanthrene at day 5 and 7. Low expression of pri-miR398 and high expression of pre-miR398 indicate that the conversion process from pri-miR398 to pre-miR398 is impeded, which causes decrease in mature miR398. The relative expression of CSD1 is entirely up-regulated, further confirming the important role of CSD1 in response to phenanthrene exposure. Besides, the overexpression of WRKY implies its potential function in answering the call from phenanthrene stress. Therefore, it is concluded that the gene silencing of CSD1 recedes due to the biosynthesis inhibition of miR398, causing the increase of SOD activity in response to phenanthrene exposure in wheat roots. Our results are useful not only for better understanding miRNAs regulation in detoxication of reactive oxygen species, but also for alleviating the toxicity to crops caused by PAHs.
显示更多 [+] 显示较少 [-]Long-term and low-dose exposure to nanopolystyrene induces a protective strategy to maintain functional state of intestine barrier in nematode Caenorhabditis elegans 全文
2020
Shao, Huimin | Wang, Dayong
Functional state of intestinal barrier plays an important role for environmental animals in being against various toxicants. We investigated GATA transcriptional factor ELT-2-mediated intestinal response to nanopolystyrere in Caenorhabditis elegans. Prolonged exposure to nanopolystyrene (≥1 μg/L) induced an increase in expression of ELT-2, and intestinal RNA interference (RNAi) knockdown of elt-2 caused enhancement in intestinal permeability. Meanwhile, mutation of elt-2 resulted in susceptibility to nanopolystyrene toxicity, and ELT-2 functioned in intestine to regulate the nanopolystyrene toxicity. ERM-1, CLEC-63, and CLEC-85 were identified as targets of ELT-2 in regulating the nanopolystyrene toxicity. ERM-1 was required for maintaining functional state in intestinal barrier, and functioned synergistically with CLEC-63 or CLEC-85 to regulate nanopolystyrene toxicity. Therefore, activation of intestinal ELT-2 by nanopolystyrere could mediate a protective strategy to maintain the functional state of intestinal barrier. During this process, intestinal ELT-2 activated two different molecular signals (ERM-1 signal and CLEC-63/85 signal) for nematodes against the nanopolystyrene toxicity.
显示更多 [+] 显示较少 [-]Effects of microplastics on growth, phenanthrene stress, and lipid accumulation in a diatom, Phaeodactylum tricornutum 全文
2020
Guo, Yahong | Ma, Wei | Li, Jiji | Liu, Wei | Qi, Pengzhi | Ye, Yingying | Guo, Baoying | Zhang, Jianshe | Qu, Chengkai
Most laboratory studies have focused on the effects of nanoplastics instead of plastics at the micrometer scale, which are the major microplastics (MPs) discarded in marine environments. Knowledge on the potential effects of micrometer scale plastics on marine microalgae remains limited. It remains unknown whether the micrometer scale plastics also affect microalgal growth, lipid accumulation and resistance to organic contaminants? In addition, the role of polymer-size on the potential hazardous effects of MPs on microalgae is unknown. In the present study, cell populations of a marine diatom, Phaeodactylum tricornutum, were treated with micrometer scale polyethylene (PEMP, 150 μm) and unplasticized polyvinyl chloride (uPVCMP, 250 μm) powders in the laboratory. Growth was assessed using a hemacytometer and neutral lipid concentrations were evaluated using the Nile Red staining method under short-term (four days) and long-term (nine days) exposure. The effects of combined PEMP and phenanthrene (Phe), and uPVCMP and Phe exposures over four days on growth were investigated. Importance scores and SHapley Additive exPlanations (SHAP) values were calculated to assess the contributions of seven factors in exposure systems to the hazardous effects of MPs on microalgae using a machine-learning prediction based on 165 data sets. Both MP types did not influence algal growth and lipid accumulation but minimized algal inhibition by the action of Phe at four days. In addition, lipid accumulation was induced at nine days. Both importance scores and SHAP values indicated that MP polymer-size was the key factor influencing MP toxicity in microalgae. In conclusion, MPs had adverse effects only in chronic tests and the potential adsorption of MPs could have led to the lower levels of toxicity in a combined MP–Phe exposure system. Compared to nanoplastics, MPs in the hundred-micrometer range do not significantly affect growth and their adsorption would not be influenced by size. Therefore, MP size is the most critical factor that should be considered in future laboratory tests and eco-toxicological risk assessments for microalgae.
显示更多 [+] 显示较少 [-]Characterization of plastic micro particles in the Atlantic Ocean seashore of Cape Town, South Africa and mass spectrometry analysis of pyrolyzate products 全文
2020
Vilakati, Bongekile | Sivasankar, V. | Mamba, Bhekie B. | Omine, Kiyoshi | Msagati, Titus A.M.
The microplastic particles with 29 pyrolyzate compounds of marine water samples from the seashore locations in Cape Town, South Africa were analysed using Pyrolysis- GC-TOF-MS. The mass spectra data documented the presence of various chemical groups that include alkanes, alkenes, dienes, fatty acids and esters, biphenyl and benzene (along with derivatives). Out of 16 identified polymers in the study area, polythene (PE) was the dominant in six out of seven locations with 87.5% followed by polyethylene terephthalate (PET) and polyvinylchloride (PVC) in five (71.4%) and four (57.1%) out of seven locations respectively. The other constituent polymers of microplastics identified through pyrolyzates were polystyrene (PS), polyamide 12 (PA-12) polyacrylic acid (PAA) and ethyl vinyl acetate (EVA) copolymer. The microplastic samples contained six additives predominantly in the family of fatty acid esters and nine plasticizers from alcohols, carboxylic esters and acids. The base peaks of m/z 41, 43, 55, 57, 69, 73, 91, 102, 105, 127 and 154 were characterized respectively with the fragmented species of C₃H₅⁺, C₃H₇⁺, C₄H₇⁺, C₄H₉⁺, C₅H₉⁺, C₃H₅O₂⁺, C₇H₇⁺, C₃H₁₀O₂⁺(McLafferty ion), C₈H₉⁺, C₈H₁₅O⁺ and C₁₂H₁₀⁺. Accordingly to Globally Harmonized System (GHS) of hazard classification, about 27.4% of pyrolyzates are Irritants, 31.4% of pyrolyzates found to be Irritants along with other hazards such as Flammable, Compressed Gas, Environmental Hazard, Corrosive, Health Hazard, Acute Toxicity and Allergy. About 41.2% of the pyrolyzates are not classified under the Irritant category. Characterizations of the plastic microparticles from the seven seashore locations such as FTIR, SEM with EDX and TGA were also done and discussed to understand the functional groups, surface morphology with elemental composition and stability respectively of the polymeric microparticles.
显示更多 [+] 显示较少 [-]Global transcriptome analysis reveals relevant effects at environmental concentrations of cypermethrin in honey bees (Apis mellifera) 全文
2020
Fent, Karl | Schmid, Michael | Christen, Verena
Cypermethrin is a frequently used insecticide in agriculture and households but its chronic and molecular effects are poorly known are . Here we describe effects of sublethal cypermethrin exposure on the global transcriptome in the brain of honey bees determined by RNA-sequencing. Exposure for 48 h to 0.3 ng/bee cypermethrin (3 ng/mL sucrose solution) causes 38 differentially expressed genes (DEGs), of which 29 are up-regulated and 9 down-regulated. Exposure to 3 ng/bee causes differential expression of 265 DEGs (209 up-, 56 down-regulated). Among the 24 DEGs shared by both concentrations are genes encoding muscular structure, muscular processes and esterase B1. Functional analysis (GO term analysis) confirms the enrichment of muscular development, structure and function among the 89 and 35 significantly altered GO terms at the low and high concentration, respectively. Up-regulation of nine DEGs determined by RT-qPCR showed a good correlation with RNA-sequence data. Among them are genes including esterase B1, titin, twitchin, mucin-19, insulin like growth factor binding protein, golgin like protein and helix loop protein. Our study demonstrates for the first time molecular effects of cypermethrin at environmental concentrations, which include expressional induction of genes encoding muscular and cellular processes and metabolism enzymes. Further studies should demonstrate the physiological consequences in bees.
显示更多 [+] 显示较少 [-]Polycyclic aromatic hydrocarbons exposure and their joint effects with age, smoking, and TCL1A variants on mosaic loss of chromosome Y among coke-oven workers 全文
2020
Liu, Yuhang | Bai, Yansen | Wu, Xiulong | Li, Guyanan | Wei, Wei | Fu, Wenshan | Wang, Gege | Feng, Yue | Meng, Hua | Li, Hang | Li, Mengying | Guan, Xin | Zhang, Xiaomin | He, Meian | Wu, Tangchun | Kwok, Woon
Mosaic loss of chromosome Y (mLOY) is the most common structure somatic event that related to increased risks of various diseases and mortality. Environmental pollution and genetic susceptibility were important contributors to mLOY. We aimed to explore the associations of polycyclic aromatic hydrocarbons (PAHs) exposure, as well as their joint effects with age, smoking, and genetic variants on peripheral blood mLOY. A total of 1005 male coke-oven workers were included in this study and their internal PAHs exposure levels of 10 urinary PAH metabolites and plasma benzo[a]pyrene-r-7,t-8,t-9,c-10-tetrahydotetrol-albumin (BPDE-Alb) adducts were measured. mLOY was defined by the median log R ratio(mLRR) of 1480 probes in male-specific region of chromosome-Y from genotyping array. We found that the PAHs exposure levels were linearly associated with mLOY. A 10-fold increase in urinary 1-hydroxynaphthalene (1-OHNa), 1-hydroxyphenanthrene (1-OHPh), 2-OHPh, 1-hydroxypyrene (1-OHP), ΣOH-PAHs, and plasma BPDE-Alb adducts could generate 0.0111, 0.0085, 0.0069, 0.0103, 0.0134, and 0.0152 decrease in mLRR-Y, respectively. Additionally, mLOY accelerated with age, smoking pack-years, and TCL1A rs1122138-C allele, and we observed the most severe mLOY among subjects carrying more than 3 of the above risk factors. Our results revealed the linear dose-effect associations between PAHs exposure and mLOY. Elder male smokers carrying rs1122138CC genotype were the most susceptible subpopulations to mLOY, who should be given protections for PAHs exposure induced chromosome-Y aberration.
显示更多 [+] 显示较少 [-]Effect of prothioconazole on the degradation of microplastics derived from mulching plastic film: Apparent change and interaction with heavy metals in soil 全文
2020
Li, Ruojia | Liu, Yi | Sheng, Yingfei | Xiang, Qingqing | Zhou, Ying | Cizdziel, James V.
Microplastic pollution is a major global environmental problem in both aquatic and terrestrial environments. Pesticides are frequently applied to agricultural soil to reduce the effects of pests on crops, but may also affect the degradation of plastics. In this study, we generated microplastics from polyethylene (PE) film and biodegradable poly(butylene adipate-co-terephthalate) (PBAT) film and determined (1) the effect of prothioconazole on degradation of the microplastics, and (2) the adsorption and release characteristics of heavy metals (Cr, Cu, As, Pb, Ba, and Sn) by the microplastics during degradation process. Changes of surface functional groups and morphologies were measured by FTIR and SEM, while metal concentrations were determined by ICPMS. Prothioconazole was found to promote plastic degradation. PBAT degraded faster and adsorbed more heavy metals from the soil than PE. Whether the microplastics adsorb or release heavy metals depended on the metal and their concentrations. Prothioconazole inhibited the adsorption of Cr, As, Pb and Ba by microplastics, promoted the adsorption of Cu, and had no significant effect for Sn. These results can help to assess the ecological risk of microplastic pollution from plastic mulch when combined with heavy metals.
显示更多 [+] 显示较少 [-]Benefits of influenza vaccination on the associations between ambient air pollution and allergic respiratory diseases in children and adolescents: New insights from the Seven Northeastern Cities study in China 全文
2020
Liu, Kangkang | Li, Shanshan | Qian, Zhengmin (Min) | Dharmage, Shyamali C. | Bloom, Michael S. | Heinrich, Joachim | Jalaludin, Bin | Markevych, Iana | Morawska, L. (Lidia) | Knibbs, Luke D. | Hinyard, Leslie | Xian, Hong | Liu, Shan | Lin, Shao | Leskinen, Ari | Komppula, Mika | Jalava, Pasi | Roponen, Marjut | Hu, Liwen | Zeng, Xiao-Wen | Hu, Wenbiao | Chen, Gongbo | Yang, Bo-Yi | Guo, Yuming | Dong, Guang-Hui
Little information exists on interaction effects between air pollution and influenza vaccination on allergic respiratory diseases. We conducted a large population-based study to evaluate the interaction effects between influenza vaccination and long-term exposure to ambient air pollution on allergic respiratory diseases in children and adolescents.A cross-sectional study was investigated during 2012–2013 in 94 schools from Seven Northeastern Cities (SNEC) in China. Questionnaires surveys were obtained from 56 137 children and adolescents aged 2–17 years. Influenza vaccination was defined as receipt of the influenza vaccine. We estimated air pollutants exposure [nitrogen dioxide (NO2) and particulate matter with aerodynamic diameters ≤1 μm (PM1), ≤2.5 μm (PM2.5) and ≤10 μm (PM10)] using machine learning methods. We employed two-level generalized linear mix effects model to examine interactive effects between influenza vaccination and air pollution exposure on allergic respiratory diseases (asthma, asthma-related symptoms and allergic rhinitis), after controlling for important covariates.We found statistically significant interactions between influenza vaccination and air pollutants on allergic respiratory diseases and related symptoms (doctor-diagnosed asthma, current wheeze, wheeze, persistent phlegm and allergic rhinitis). The adjusted ORs for doctor-diagnosed asthma, current wheeze and allergic rhinitis among the unvaccinated group per interquartile range (IQR) increase in PM1 and PM2.5 were significantly higher than the corresponding ORs among the vaccinated group [For PM1, doctor-diagnosed asthma: OR: 1.89 (95%CI: 1.57–2.27) vs 1.65 (95%CI: 1.36–2.00); current wheeze: OR: 1.50 (95%CI: 1.22–1.85) vs 1.10 (95%CI: 0.89–1.37); allergic rhinitis: OR: 1.38 (95%CI: 1.15–1.66) vs 1.21 (95%CI: 1.00–1.46). For PM2.5, doctor-diagnosed asthma: OR: 1.81 (95%CI: 1.52–2.14) vs 1.57 (95%CI: 1.32–1.88); current wheeze: OR: 1.46 (95%CI: 1.21–1.76) vs 1.11 (95%CI: 0.91–1.35); allergic rhinitis: OR: 1.35 (95%CI: 1.14–1.60) vs 1.19 (95%CI: 1.00–1.42)]. The similar patterns were observed for wheeze and persistent phlegm. The corresponding p values for interactions were less than 0.05, respectively. We assessed the risks of PM1-related and PM2.5-related current wheeze were decreased by 26.67% (95%CI: 1.04%–45.66%) and 23.97% (95%CI: 0.21%–42.08%) respectively, which was attributable to influenza vaccination (both p for efficiency <0.05).Influenza vaccination may play an important role in mitigating the detrimental effects of long-term exposure to ambient air pollution on childhood allergic respiratory diseases. Policy targeted at increasing influenza vaccination may yield co-benefits in terms of reduced allergic respiratory diseases.
显示更多 [+] 显示较少 [-]Developmental toxicity and neurotoxicity of penconazole enantiomers exposure on zebrafish (Danio rerio) 全文
2020
Jia, Ming | Teng, Miaomiao | Tian, Sinuo | Yan, Jin | Meng, Zhiyuan | Yan, Sen | Li, Ruisheng | Zhou, Zhiqiang | Zhu, Wentao
Penconazole is a widely used chiral triazole bactericide that may adversely affect the environment. It contains two corresponding enantiomers and there may be differences in toxicity between the isomers. Therefore, in this study, we exposed zebrafish embryos to different concentrations of the penconazole enantiomer to study the developmental toxicity and neurotoxicity of penconazole on zebrafish and the difference in toxicity between enantiomers. The results showed that penconazole exposure caused adverse effects on zebrafish embryos, such as autonomous motor abnormalities, heart rate slowing, and increased deformity, resulting in significant developmental toxicity. Meanwhile, also caused the zebrafish larvae to slow movement, the neurotransmitter content and nervous system related gene expression significantly changed, which proved that penconazole also caused neurotoxicity to zebrafish. Interestingly, our results also clearly show that (+)-penconazole is significantly more toxic to zebrafish than (−)-penconazole at the same concentration, whether it is developmental toxicity or neurotoxicity, which suggests that we should focus on (+)-penconazole more when conducting toxicological studies on penconazole.
显示更多 [+] 显示较少 [-]Effects of treatment agents during acid washing and pH neutralization on the fertility of heavy metal-impacted dredged marine sediment as plant-growing soil 全文
2020
Kim, Kibeum | Yoon, Sangwon | Kwon, Hyun-ah | Choi, Yongju
The present study was aimed at investigating the effects of different acids and pH neutralizers applied to dredged marine sediment for the treatment of heavy metals, and the resulting influence on the sediment quality as a plant growth medium. The inspection of barley germination in the dredged marine sediment revealed that residual salts are critical plant stressors whose adverse effects exceed those exhibited by high-level heavy metals and petroleum hydrocarbons present in the sediment. Acid washing and pH neutralization reduced not only the heavy metal contents but also the sediment salinity (by factors of 6.1–9.5), resulting in 100% germination of barley. For acid-washed and calcium-oxide-neutralized sediment, the barley growth was comparable to that observed in untreated and water washed sediment despite factors of 5.2–8.0 greater sediment salinity in the former. This result represents the protective effect of residual calcium against sodium and chloride toxicity. Water washing of acid-washed and pH-neutralized sediments further enhanced barley growth owing to the reduction in osmotic pressure. This study showed the effect of different sediment-washing reagents on the product quality. It also indicated the significance of balancing the enhancement of product quality and economic cost of further treatment requirements.
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