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Zearalenone and deoxynivalenol reduced Th1-mediated cellular immune response after Listeria monocytogenes infection by inhibiting CD4+ T cell activation and differentiation 全文
2021
Cai, Guodong | Xia, Sugan | Zhong, Fang | Liu, Shuangshuang | Gu, Jianhong | Yuan, Yan | Zhu, Guoqiang | Zou, Hui | Liu, Zongping | Bian, Jianchun
Based on the fact that mycotoxins and the food-borne bacteria coexist in the natural environment and pose a significant health hazard to humans and animals, it is important to investigate the immunosuppressive mechanism of ZEA (zearalenone), DON (deoxynivalenol), and their combination in bacterial infections. In this study, we established a mouse model of mycotoxin low-dose exposure combined with Listeria monocytogenes infection and investigated the effects of ZEA, DON and their combination on Th1-mediated anti-intracellular bacterial infection based on CD4⁺ T cell activation and differentiation using both in vitro and in vivo analyses. The present study showed that both ZEA and DON aggravated Listeria monocytogenes infection in mice and affected the activation of CD4⁺ T cells and Th1 differentiation, including the effects on costimulatory molecules CD28 and CD152 and on cross-linking of IL-12 and IL-12R, by inhibiting T cell receptor (TCR) signaling. When compared with ZEA, DON was found to have a greater impact on many related indicators. Surprisingly, the combined effects of ZEA and DON did not appear to enhance toxicity compared to treatment with the individual mycotoxins. Our findings more clearly revealed that exposure to low-dose ZEA and DON caused immunosuppression in the body by mechanisms including inhibition of CD4⁺ T cells activation and reduction of Th1 cell differentiation, thus exacerbating infection of animals by Listeria monocytogenes.
显示更多 [+] 显示较少 [-]Integrated transcriptomics and proteomics revealed the distinct toxicological effects of multi-metal contamination on oysters 全文
2021
Li, Yunlong | Wang, Wen-Xiong
The Pearl River Estuary (PRE) is the largest estuary in southern China and under high metal stress. In the present study, we employed an integrated method of transcriptomics and proteomics to investigate the ecotoxicological effects of trace metals on the Hong Kong oyster Crassostrea hongkongensis. Three oyster populations with distinct spatial distributions of metals were sampled, including the Control (Station QA, the lowest metal levels), the High Cd (Station JZ, the highest Cd), and the High Zn–Cu–Cr–Ni (Station LFS, with the highest levels of zinc, copper, chromium, and nickel). Dominant metals in oysters were differentiated by principal component analysis (PCA), and theirgene and protein profiles were studied using RNA-seq and iTRAQ techniques. Of the 2250 proteins identified at both protein and RNA levels, 70 proteins exhibited differential expressions in response to metal stress in oysters from the two contaminated stations. There were 8 proteins altered at both stations, with the potential effects on mitochondria and endoplasmic reticulum by Ag. The genotoxicity, including impaired DNA replication and transcription, was specifically observed in the High Cd oysters with the dominating influence of Cd. The structural components (cytoskeleton and chromosome-associated proteins) were impaired by the over-accumulated Cu, Zn, Cr, and Ni at Station LFS. However, enhanced tRNA biogenesis and exosome activity might help the oysters to alleviate the toxicities resulting from their exposure to these metals. Our study provided comprehensive information on the molecular changes in oysters at both protein and RNA levels in responding to multi-levels of trace metal stress.
显示更多 [+] 显示较少 [-]Where are we? Towards an understanding of the selective accumulation of microplastics in mussels 全文
2021
Li, Jiana | Wang, Zhenglu | Rotchell, Jeanette M. | Shen, Xiaoteng | Li, Qipei | Zhu, Jingmin
Mussels are suggested as bioindicators of marine microplastic pollution. However, they are selective in regards to accumulation of microplastics. To make studies more targeted and comparable, ultimately helping to determine the suitability of the mussel as a bioindicator species for microplastic exposure, we review the published literature that has directly or indirectly demonstrated particle selection in mussels. The reported difference between microplastic levels in mussel tissues and environmental matrices provides evidence for their selective uptake characteristics. Both the organ-specific fate characteristics of microplastics, and the different movement patterns of microplastics in the same organ, show that selective translocation processes take place. The selective elimination is reflected in multiple aspects which include (1) the different characteristics of microplastics in excretion and mussel body; (2) the different retention time of various microplastics in mussels; and (3) the tissue-specific change in the numbers of microplastics during the depuration process. This selectivity is affected by the characteristics of the microplastics, the environmental, or laboratory exposure concentrations, feeding status, and other factors. There are still many research gaps and contradictory viewpoints in this field due to this complexity. The current methodology needs improvement and a breakthrough in standardization.
显示更多 [+] 显示较少 [-]Evaluating the effectiveness of green marketing of socio-economic organizations in reducing environmental pollution 全文
2021
Hojjat Nazari | Sadegh Zibakalam | Mohammad Reza Parvin
The purpose of this study is to measure and evaluate the effectiveness of environmental advertising related to green marketing by organization. In other words, the researcher seeks to find the success rate of environmental advertising in reducing environmental pollution. The type of goal is an application that has been done by descriptive-survey method. A researcher-made questionnaire was used to collect data. The statistical populations of the study were consumers of environmental friendly goods in Tehran. Confirmatory factor analysis method and SPSS, Version21 and AMOS (2016) software were used for data analysis. The results showed that the models for measuring the research variables are appropriate models. Because the value of Ï2 and the value of RMSEA are low and also the values of AGFI, GFI and NFI are greater than 0.9 and the significance level of factor loads is less than 5%, which indicates the significance of the relationship defined in the measurement models. Also, the effect of communication stimuli on the cognitive and emotional response of consumers and then the effect of content stimuli on the cognitive and emotional response of users in this study has the highest influence. However, neither content nor communication stimuli have influenced consumer attitudes.
显示更多 [+] 显示较少 [-]Investigation of physicochemical properties of water in downstream areas of selected dams in Aras catchment and water quality assessment (Case study: Aras catchment in the border area of Iran and Armenia) 全文
2021
Ebrahim Safizadeh | Dariush Karimi | Hamid Reza Gahfarzadeh | Seyed Abbas Pourhashemi
The aim of this study was to evaluate the physicochemical properties of downstream water of Aras river dams. Sampling was performed from early 2018-2019 in selected stations. Heavy metals were measured by atomic absorption spectrometry. Nitrate, nitrite and total dissolved solids concentrations were also measured by spectrophotometer. Concentrations of Ca, Na and K were measured with a Flame Photometer and the rest were measured with specialized devices. The results showed that the lowest electrical conductivity in the measured samples was 0.789 and the highest was 4.346 µs/cm, which basically indicates the high limit of soil and water for irrigation of plants. On the other hand, total solids with 1211 ppm indicate a moderate limit for salinity. Also; regarding pH, the average recorded for the study area is 8.17, which is within the national permissible and standard range of the world health organization. Nitrate and nitrite are both above the permissible and standard range. Potassium is within the permitted and standard range. Calcium, according to the average obtained in the study area (64 ppm) can be said that this parameter is within the allowable and standard range. In the case of lead (0.09 ppb), it can be said that this parameter is within the allowable and standard range. In the case of cadmium (0.8 ppb), it can be said that this parameter is within the allowable and standard range, 3 parameters nitrate, nitrite and TDS have an average higher than the national standard.
显示更多 [+] 显示较少 [-]Removal of Malathion on Carbon using Iron Oxide Nanoparticles (Fe3O4) in Aquatic Environments 全文
2021
Malektaj Eskandari Makvand | Sima Sabzalipour | Mahboobeh Cheraghi | Neda Orak
The development of nanotechnology and the possible entry of nanoparticles into aquatic environments have raised environmental concerns. The present study aimed to investigate the effect of iron oxide nanoparticles (Fe3O4) loaded on carbon to remove malathion in order to evaluate the toxicity potential of nanoparticles in aqueous environments. We examined the characteristics of iron oxide nanoparticles (Fe3O4) using XRD refraction, Fourier irradiated spectroscopy (FTIR), the catalytic activity of iron nanoparticles for activation of persulfate, and malathion decomposition. Moreover, we assessed the influence of effective parameters on this process, such as pH, persulfate concentration, and the number of iron oxide nanoparticles (Fe3O4). The results showed that 82% of malathion was decomposed by the combined process of iron oxide nanoparticles loaded on carbon at pH=5 and 0.4 g of iron nanoparticles in 60 minutes. Additionally, according to the results obtained from the advanced oxidation processes, it was able to optimally remove malathion from the aquatic environment. This study revealed that nanoparticle stabilization technology on activated carbon could be used as an effective, efficient, and fast adsorbent to remove certain contaminants, such as malathion, from aqueous solutions. Although the combination of processes may complicate their analysis and mechanism, the study of this process could be a promising emergence of hybrid processes in water and wastewater treatment. In general, the results of this study relatively indicated that the physicochemical properties of nanoparticles, such as size, shape, surface, general morphology, and chemical composition, in different environmental conditions can significantly affect carbon in removing the malathion
显示更多 [+] 显示较少 [-]Application of Steam Enhanced Extraction method on BTEX contaminated soil in a Nigerian petroleum depot and Automobile workshop sites in Ilorin metropolis, Nigeria. 全文
2021
Ismail Muhibbu-din | Isaac Ayodele
. Benzene, toluene, ethyl benzene and xylene (BTEX) are major causes of contaminated soil. This is due to fuel leakages or spillages, various forms hydrocarbon burning/combustion and land disposal petroleum base oil. Contaminated soil samples were excavated from two different locations within Ilorin metropolis; pipelines and products marketing company, a Nigerian petroleum depot, Ilorin depot and auto mechanic workshop of over ten years. Steam enhanced extraction method was employed through injection of steam to contaminated soil from steam generator into soil pot where contaminated soil was placed. After the remediation process the steam soil samples were taken to the laboratory where the sonication extraction technique was used to extract the contaminants (BTEX) from the steamed soil samples of 30, 60 and 90 minutes respectively. The extract from the steamed soil samples of 30, 60 and 90 minutes were subjected Gas Chromatography fitted with flame ionization detector analysis to determine the exact amount of BTEX removed after remediation process. Pre-treated soil sample of auto mechanics workshop was found to be 4.5004 x 10-1 mg/kg and post-treated soil samples were found to be 1.8164 x10-1 mg/kg, 8.7519 x10-1 mg/kg and 5.7006 x10-2 mg/kg for 30, 60 and 90 minutes respectively after remediation process while Pre-treated soil sample of a Nigerian petroleum depot was found to be 6.6049 x 10-1 mg/kg and post-treated soil samples were found to be 2.9320 x10-1 mg/kg, 1.9855 x10-1 mg/kg and 1.0237 x10-1 mg/kg for 30, 60 and 90 minutes respectively after remediation process
显示更多 [+] 显示较少 [-]Modelling fuzzy multi-criteria decision-making method to locate industrial estates based on geographic information system 全文
2021
Mohammad Reza Jangjoo
Existing conditions for locating urban equipment and facilities require a set of limiting and reinforcing factors. Interaction of environmental, industrial, social and political changes in our rapid growth adds to the complexity of regional systems. Locating takes place by various methods, in which the priority is the application of modern methods leading to reduced uncertainty. The present study aimed to select the best location using nine criteria (slope, distance from fault, distance from river, distance from road, and distance from villages, soil type, land use, average temperature, and average rainfall) in GIS software for mapping. Fuzzy logic and fuzzy-analytical hierarchy process (FAHP) model were applied to reduce location uncertainty. The accuracy of the results was checked using field data, in which six stations designated for the establishment of industrial estates in the study area were compared with the results of the FAHP model. The results of FAHP model in GIS software and their validation showed that the proposed model has excellent capabilities in locating industrial estates.
显示更多 [+] 显示较少 [-]Polycyclic aromatic compounds in the Canadian Environment: Aquatic and terrestrial environments 全文
2021
Marvin, Christopher H. | Berthiaume, Alicia | Burniston, Deborah A. | Chibwe, Leah | Dove, Alice | Evans, Marlene | Hewitt, L Mark | Hodson, Peter V. | Muir, Derek C.G. | Parrott, Joanne | Thomas, Philippe J. | Tomy, Gregg T.
Polycyclic aromatic compounds (PACs) are ubiquitous across environmental media in Canada, including surface water, soil, sediment and snowpack. Information is presented according to pan-Canadian sources, and key geographical areas including the Great Lakes, the Alberta Oil Sands Region (AOSR) and the Canadian Arctic. Significant PAC releases result from exploitation of fossil fuels containing naturally-derived PACs, with anthropogenic sources related to production, upgrading and transport which also release alkylated PACs. Continued expansion of the oil and gas industry indicates contamination by PACs may increase. Monitoring networks should be expanded, and include petrogenic PACs in their analytical schema, particularly near fuel transportation routes. National-scale roll-ups of emission budgets may not expose important details for localized areas, and on local scales emissions can be substantial without significantly contributing to total Canadian emissions. Burning organic matter produces mainly parent or pyrogenic PACs, with forest fires and coal combustion to produce iron and steel being major sources of pyrogenic PACs in Canada. Another major source is the use of carbon electrodes at aluminum smelters in British Columbia and Quebec. Temporal trends in PAC levels across the Great Lakes basin have remained relatively consistent over the past four decades. Management actions to reduce PAC loadings have been countered by increased urbanization, vehicular emissions and areas of impervious surfaces. Major cities within the Great Lakes watershed act as diffuse sources of PACs, and result in coronas of contamination emanating from urban centres, highlighting the need for non-point source controls to reduce loadings.
显示更多 [+] 显示较少 [-]Intensive vegetable production results in high nitrate accumulation in deep soil profiles in China 全文
2021
Bai, Xinlu | Jiang, Yun | Miao, Hongzhi | Xue, Shaoqi | Chen, Zhujun | Zhou, Jianbin
A comprehensive understanding of the patterns and controlling factors of nitrate accumulation in intensive vegetable production is essential to solve this problem. For the first time, the national patterns and controlling factors of nitrate accumulation in soil of vegetable systems in China were analysed by compiling 1262 observations from 117 published articles. The results revealed that the nitrate accumulation at 0–100 cm, 100–200 cm, 200–300 cm, and >300 cm were 504, 390, 349, and 244 kg N ha⁻¹, with accumulation rates of 62, 54, 19, and 16 kg N ha⁻¹ yr⁻¹ for plastic greenhouse vegetables (PG); for open field vegetables (OF), they were 264, 217, 228, and 242 kg N ha⁻¹ with accumulation rates of 26, 24, 18, and 10 kg N ha⁻¹ yr⁻¹, respectively. Nitrate accumulation at 0–100 cm, 0–200 cm, and 0–400 cm accounted for 5%, 11%, and 17% of accumulated nitrogen (N) inputs for PG, and represented 4%, 9%, and 13% of accumulated N inputs for OF. Nitrogen input rates and soil pH had positive effects and soil organic carbon, water input rate, and carbon to nitrogen ratio (C/N) had negative effects on nitrate accumulation in root zone (0–100 cm soil). Nitrate accumulation in deep vadose zone (>100 cm soil) was positively correlated with N and water input rates, and was negatively correlated with soil organic carbon, C/N, and the clay content. Thus, for a given vegetable soil with relatively stable soil pH and soil clay content, reducing N and water inputs, and increasing soil organic carbon and C/N are effective measures to control nitrate accumulation.
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