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Therapeutical properties of Mimosa caesalpiniifolia in rat liver intoxicated with cadmium Full text
2020
de Lima, Eliene Cezario | de Moura, Carolina Foot Gomes | Silva, Marcelo Jose Dias | Vilegas, Wagner | Santamarina, Aline Boveto | Pisani, Luciana Pellegrini | de Oliveira, Flavia | Ribeiro, Daniel Araki
The aim of this study was to evaluate the therapeutic properties of Mimosa caesalpiniifolia in liver of rats exposed to cadmium under morphological, oxidative, inflammatory, and mutagenic parameters. A total of 40 Wistar rats (90 days, ~ 250 g) were distributed into eight groups (n = 5) as follows: (i) control; (ii) cadmium: cadmium chloride injection at 1.2 mg/kg; (iii) Mimosa extract: treatment with Mimosa extract at 250 mg/kg; (iv) Mimosa fraction: treatment with Mimosa acetate fraction at 62.5 mg/kg; (v) cadmium and Mimosa extract 62.5: submitted to cadmium chloride at 1.2 mg/kg injection and treatment with Mimosa extract at 62.5 mg/kg; (vi) cadmium and Mimosa extract 125: subjected to cadmium chloride at 1.2 mg/kg injection and treatment with Mimosa extract at 125 mg/kg; (vii) cadmium and Mimosa 250 extract: submitted to cadmium chloride 1.2 mg/kg injection and treatment with Mimosa extract at 250 mg/kg; (viii) cadmium treated with fraction of Mimosa acetate: submitted to cadmium chloride 1.2 mg/kg injection and treatment with acetate fraction of Mimosa extract at 62.5 mg/kg. In the animals intoxicated with cadmium and treated with fraction [62.5], increased expression of SOD-Mn reduced frequency of binucleated hepatocytes, karyolysis, and karyorrhexis, besides the antimutagenic and antioxidant action. The extract [62.5] was cytoprotective, antimutagenic, and reduced karyolysis. The extract [125] was cytoprotective, antioxidant, antifibrotic, anti-inflammatory, and reduced frequency of binucleated hepatocytes, while extract [250] was cytotoxic and mutagenic. In summary, the extract of Mimosa exerts some therapeutic properties in hepatic tissue after Cd intoxication, but only when it is administrated at intermediate doses. Probably, a high content of polyphenols in the EHM [250] and Fr-EtOAc groups exert pro-oxidant activities in the liver particularly when associated with Cd.
Show more [+] Less [-]Combined toxicity of imidacloprid, acetochlor, and tebuconazole to zebrafish (Danio rerio): acute toxicity and hepatotoxicity assessment Full text
2020
Chang, Yiming | Mao, Liangang | Zhang, Lan | Zhang, Yanning | Jiang, Hongyun
Compound pollution refers to two or more kinds of pollutants with different properties, a pollutant from different sources, or the simultaneous existence of two or more different types of pollutants in the same environment. In this study, we aimed to investigate the individual and combined toxicity of the insecticide imidacloprid (IMI), the herbicide acetochlor (ACT), and the fungicide tebuconazole (TBZ) to zebrafish. The acute toxicity test results showed that the 96-h LC₅₀ values of IMI, ACT, and TBZ were 276.84 (259.62–294.35) mg active ingredient (a.i.) L⁻¹, 1.52 (1.34–1.74) mg a.i. L⁻¹, and 8.16 (7.7–8.6) mg a.i. L⁻¹, respectively. The combinations of IMI, ACT, and TBZ with toxicity ratios of 1:2:2, 1:4:4, 2:4:1, and 4:1:4 displayed synergistic toxic effects on zebrafish, while the toxicity ratios of 1:1:1, 1:1:2, 2:1:2, 2:2:1, and 4:2:1 of IMI, ACT, and TBZ, respectively, exhibited antagonistic toxic effects on zebrafish. The following experiments were performed with a toxicity ratio of 1:4:4 (IMI:ACT:TBZ). The activities of four enzyme biomarkers related to oxidative stress in the liver, catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), and malondialdehyde (MDA) content were evaluated in each exposure group on days 7, 14, 21, and 28. Compared with those of the control group, the activities of CAT, SOD, and GST and the MDA content were significantly altered at different time points in the individual and combined exposure groups. Additionally, the activities of CAT, SOD, and GST and the MDA content were significantly altered in the combined group compared with those of the individual group after 14 days or 21 days of exposure. Therefore, it was confirmed that combined toxicity studies are indispensable in risk assessment. Graphical abstract .
Show more [+] Less [-]Improving environmental protection of waterborne polyurethane coating by adding TiO2/polyaniline/HNT/CNT nanocomposite Full text
2020
Nosrati, Rahimeh | Kiani, Gholamreza | Karimzad Ghavidel, Ayub | Rashīdī, ʻAlī
Nanostructures of titanium dioxide, polyaniline, halloysite, and carbon nanotubes have an excellent effect to improve environmental protection and surface properties of coatings like anticorrosion and self-cleaning attributes. In this research, we studied the individual effect of adding each nanostructure within the polyurethane matrix and also all nanostructure combinations with each other on the mentioned properties. To reach this aim, the polyurethane nanocomposites were prepared; then, anticorrosion and self-cleaning tests were carried out on the samples. FTIR spectroscopy and FESEM images were used to characterize the nanocomposite additives and coating influence. According to the obtained results, the polyurethane coating modified with titanium dioxide/polyaniline/halloysite nanotube/carbon nanotube nanocomposite showed very higher corrosion potential and resistance and lower corrosion current in the comparison with other coatings. Also, the mentioned polyurethane nanocomposite coating showed good hydrophilicity and it decolorized a dye contaminant with high efficiency which makes them appropriate candidate for the protection of the substrate against environmental destructive factors.
Show more [+] Less [-]Development of an activated carbon impregnation process with iron oxide nanoparticles by green synthesis for diclofenac adsorption Full text
2020
Silveira, Carole | Shimabuku-Biadola, Quelen Letícia | Silva, Marcela Fernandes | Vieira, Marcelo Fernandes | Bergamasco, Rosângela
The objective of this study was to impregnate the surface of palm coconut activated carbon with nanoparticles of iron compounds using Moringa oleifera leaf extracts and pomegranate leaf by a green synthesis method and to evaluate its adsorption capacity for sodium diclofenac. The adsorbent material was characterized by zeta potential, X-ray diffraction (XRD), N₂ adsorption/desorption (BET method), transmission electronic microscopy (TEM), and scanning electronic microscopy (SEM) coupled to dispersive energy spectrometry X-ray (EDX) methods. To evaluate the adsorption capacity of sodium diclofenac, the influence of pH, kinetics, isotherms, and thermodynamic properties were analysed. The impregnated adsorbents showed efficiency in the adsorption of sodium diclofenac. The kinetic model that best fit the experimental data was the pseudo-second-order model, and the equilibrium model was the Langmuir model. As for the thermodynamic study, it was verified that the adsorption reaction for all adsorbents occurs in a spontaneous, favourable way, and it is endothermic by physisorption. Therefore, this process is promising because it is a clean and non-toxic method when compared with chemical methods for the synthesis of nanoparticles.
Show more [+] Less [-]The effect of biochar on severity of soil water repellency of crude oil-contaminated soil Full text
2020
Ebrahimzadeh Omran, Samaneh | Shorafa, Mehdi | Zolfaghari, Ali Asghar | Soltani Toolarood, Ali Ashraf
Crude oil contamination adversely affects soil water repellency. In this study the effect of biochar on this soil characteristic has been investigated in the laboratory. Soil sample was collected from a field located near Pars Oil Company, at the top depth of 0–15 cm below surface. After air-drying and passing through a 2-mm sieve, the soil was artificially contaminated with four levels of crude oil (1:0, 1:25, 1:16.6, and 1:12.5 ratios). Biochars used in this research were generated from beechwood and maize residues at three different pyrolysis temperatures (350 °C, 550 °C, and 750 °C). Chemical functionality of all biochar samples was determined using Fourier-transform infrared spectrometry. Sufficient amounts of beechwood and maize biochars, passed through a 0.053-mm and 2-mm sieves, were mixed into crude oil-contaminated soil at the rate of 0, 0.5, 1, and 2% of total dry soil weight. The mixed samples were then laboratory incubated for 90 days at 24 °C and 10% soil moisture. Water repellency was measured using water drop penetration time (WDPT). The experimental results showed that functional groups on the biochars’ surfaces produced at the studied temperatures were distinct. Beechwood and fine size of biochar showed more ability in reducing the hydrophobicity. The produced biochars, at higher temperature, had more potential to alleviate water repellency due to the strong interactions between functional groups of biochars and crude oil. The highest amount of biochar used (2%) significantly alleviated water repellency.
Show more [+] Less [-]Assessment on the effectiveness of environmental regulation in China—evidence from a panel data analysis Full text
2020
Lai, Xiaodong | Liu, Zhiming | Luo, Sumei
In the context of global warming and environmental deterioration, the environment impact assessment is a crucial institutional guaranty to assure less or no pollution during the process of the economic growth and rapid social development. This paper selected the environmental regulation system in China as a research target and assesses the effectiveness of green tax on the environment through an empirical analysis. The panel data from 2005 to 2015 in different cities in China are employed to analyze with a two-way fixed regression model; it analyzes the impact of environmental instruments like resource tax, excise tax, vehicle purchase tax, and pollutant discharge fees on environmental pollution and finds that the modeling conditions with green tax reform can lead to higher effect on environmental pollutant constrain but is distributed differently among east, central, and west based on the empirical analysis in China. Moreover, resource tax has a significant effect in the east and midwest of China. The effectiveness of excise tax on integrated pollution is not statistically significant. Compared with the midwest, eastern China’s green tax had a much better performance on reducing environmental pollution. Pollutant discharge fees indicates a significant negative correlation to integrated pollution. The consumption of the other goods (like meat consumption) plays a mediating effect between vehicle purchase tax and integrated environmental pollution. In addition, the relevant policy recommendations are proposed against different tax types.
Show more [+] Less [-]Water consumption assessment in Asian chemical industries supply chains based on input–output analysis and one-way analysis of variance Full text
2020
Shafiei, Mahboobe | Moosavirad, Seyed Hamed | Azimifard, Arezoo | Biglari, Shirin
Chemical sector contributes extensively to the economic development of countries, however, it is one of the main water-consuming industries. Considering that the corporate water accounting along complete SCs can help companies in improving their sustainable water managements along their value chains, this paper aims to study the water consumption in the entire supply chain of the chemical industry from a multi-regional input-output perspective. In this regard, six Asian countries including Indonesia, Taiwan, China, Japan, South Korea and India are selected to be studied based upon the availability of their data. In the following, the direct water consumed by themselves and the indirect water used by their suppliers are measured for each country using input-output analysis method. Moreover, to draw on the conclusions of selected Asian countries, the amount of consumed water in their supply chains is compared with each other using one-way analysis of variance method. The results from input-output analysis show that the indirect water consumption in the chemical SCs of Indonesia, China, India and South Korea are 20.66, 4.62, 1.37 and 1.08 times greater than their direct water use, while the indirect water consumption for Japan and Taiwan are 0.73 and 0.13 times less than their direct values. The final results from one-way analysis of variance indicate that direct and indirect amount of water consumptions in the chemical supply chains of the selected countries do not follow the same trend over 15 years. However, India and China are the top two countries in terms of both direct and indirect amounts of water consumption due to their higher population. This study presents valuable information for authorities and policymakers in terms of proper water consumption management in chemical industry and other industrial sectors. In this matter, technology-based or production-related actions are beneficiary for affecting direct water use, while consumption-based or end-use actions are more appropriate for affecting indirect water consumption.
Show more [+] Less [-]Determination of trace elements in Sergio mirim: an evaluation of sample preparation methods and detection techniques Full text
2020
Mandlate, Jaime S. | Soares, Bruno M. | Andrade, Carlos F. F. | Colling, Leonir A. | Primel, Ednei G. | Mesko, Marcia F. | Duarte, Fabio A.
In this work, some trace elements (As, Cd, Cr, Cu, and Pb) were determined for the first time in the crustacean Sergio mirim (Decapoda: Thalassinidea: Callianassidae) from Southern Coast (Rio Grande, RS) of Brazil. The trace element determination was carried out by graphite furnace atomic absorption spectrometry (GF AAS) and inductively coupled plasma mass spectrometry (ICP-MS). Different microwave radiation-based sample digestion methods were evaluated. The analyte concentration ranged from 1.45 to 3.70 μg g⁻¹ for As, 0.615 to 0.942 μg g⁻¹ for Cd, 0.884 to 7.20 μg g⁻¹ for Cr, 122 to 275 μg g⁻¹ for Cu, and 0.390 to 0.916 μg g⁻¹ for Pb. The limits of quantification for As, Cd, Cr, Cu, and Pb were 0.12, 0.01, 0.16, 0.92, and 0.06 μg g⁻¹, respectively. The accuracy was evaluated by results comparison between GF AAS and ICP-MS techniques, as well as by analysis of certified reference materials of fish muscle and oyster tissue, with agreement from 92 to 108%. The feasibility of using Sergio mirim as a promising environmental bioindicator candidate was evaluated, since that it is an abundant organism in the studied area (South cost of Brazil) as well as in other places around the world.
Show more [+] Less [-]Mechanism study of enhanced interaction between gaseous elemental mercury and hydroxylated UIO-66 Full text
2020
Zhou, Changsong | Zhu, Wenxin | Chang, Xiong | Ding, Ding | Zhang, Tingting | Chen, Jiamin | Wu, Hao | Yang, Hongmin | Sun, Lushi
Novel hydroxylated UIO-66 for gaseous elemental mercury (Hg⁰) removal has been considered to be an emerging method because of its economical and reusable property. Density functional theory studies were investigated to reveal the enhanced heterogeneous interaction mechanisms between mercury and hydroxylated UIO-66 with and without the presence of H₂O₂ vapor. The adsorption and dissociation of H₂O₂ and the generation mechanism of surface hydroxyls on UIO-66 were investigated. Results indicated that H₂O₂ preferred to disconnect the O–O bond followed by the generation of two hydroxyls in the presence of H₂O₂. The hydroxyl adsorbed on UIO-66 and formed the UIO-66 hydroxylation product. The interaction performances between Hg⁰, H₂O₂, and UIO-66 as well as the interaction performances between Hg⁰ and hydroxylated UIO-66 systems were both evaluated through binding energy and the Mulliken charge analysis. Interacted energies indicated thermodynamically favorable processes of Hg–OH formation on hydroxylated UIO-66. The Mulliken charge changes revealed an oxidative process of mercury.
Show more [+] Less [-]Protective effects of Citrus limonia oil against cisplatin-induced nephrotoxicity Full text
2020
Abdel-Daim, Mohamed M. | Mahmoud, Omayma M. | Al Badawi, Manal H. | Alghamdi, Jawahir | Alkahtani, Saad | Salem, Noha A.
Cisplatin is broadly used in the treatment of malignancies. However, the high incidence of nephrotoxicity following cisplatin use deters its clinical utility. Former studies have shown that the essential oils, obtained from Citrus limonia demonstrated significant anti-inflammatory and antioxidant effects. The aim of the current work was to evaluate the protective effects of Citrus limonia oil against cisplatin-induced nephrotoxicity. Thirty-two adult male mice were divided into four groups, eight mice each. The control group received distilled water, and the second group received a single intraperitoneal injection of cisplatin (20 mg/kg), while the third and fourth groups received cisplatin plus Citrus limonia oil at 100 or 200 mg/kg for 10 days, respectively. GC-MS analysis showed that the major components in Citrus limonia oil were D-limonene, 5-methyl-pentadecane, (n)-menthol, 3,7-dimethyl-(E)-2,6-octadienal, 3,7-dimethyl-2,6-octadienal, and nonadecane. Biochemical analysis showed that cisplatin intoxication was associated with significantly increased (p < 0.05) serum levels of urea and creatine and pro-inflammatory cytokines, as well as augmented renal tissue oxidative stress. Light microscopic examination showed loss of renal architecture, atrophied glomeruli, interstitial hemorrhage, dilated cortical tubules with cast formation, and excessive collagen production. Electron microscopic examination revealed compressed and karyorrhectic endothelial nuclei with chromatin condensation in the glomeruli, accumulation of mesangial matrix, and obliteration of glomerular blood capillaries. Co-administration of Citrus limonia oil attenuated these effects in renal histopathological, morphometric, and ultrastructural examinations, frequently in a dose-dependent manner. In conclusion, Citrus limonia oil can ameliorate the toxic effect of cisplatin on mice kidneys, probably through its antioxidant and anti-inflammatory effects.
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