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Curcumin attenuates nephrotoxicity induced by zinc oxide nanoparticles in rats Full text
2019
Heidai-Moghadam, Abbas | Khorsandi, Layasadat | Jozi, Zahra
Curcumin (Cur) effects on renal injury induced by zinc oxide nanoparticles (NZnO) in rats were investigated. NZnO at a dose of 50 mg/kg for 14 days was administered to rats as intoxicated group. In protection group, Cur at a dose of 200 mg/kg was administered for 7 days prior to NZnO treatment and followed by concomitant administration of NZnO for 14 days. Plasma concentrations of uric acid, creatinine (Cr), and blood urea nitrogen (BUN) were detected to evaluate renal injury. Malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx) levels were determined for evaluation oxidative stress. TUNEL staining and histological changes were also performed. Administration of NZnO caused a significant elevation in the uric acid, Cr, and BUN levels. Oxidative stress was increased in the kidney by NZnO through enhancing MDA contents and reducing activities of SOD and GPx enzymes. According to histological examinations, treatment with NZnO caused proximal tubule damages, which was accompanied by the accumulation of red blood cells, infiltration of inflammatory cells, and reducing glomerular diameters. Significant increase was observed in the apoptotic index of the renal tubules in NZnO-treated rats. In present work, pretreatment of Cur reduced the histological changes, decreased biomarker levels, attenuated apoptotic index, and ameliorated oxidative stress by decreasing the MDA contents and increasing the activities of SOD and GPx enzymes. These findings indicate that Cur effectively protects against NZnO-induced nephrotoxicity in the rats.
Show more [+] Less [-]A comprehensive study on emission and performance characteristics of a diesel engine fueled with nanoparticle-blended biodiesel Full text
2019
Devarajan, Yuvarajan | Nagappan, Beemkumar | Subbiah, Ganesan
The present work is aimed to analyze the performance and emission characteristics of mahua biodiesel-fueled diesel engine with copper oxide nanoparticle at various particle sizes (10 and 20 nm) and the results compared with conventional diesel fuel (BD). Experiments were conducted in a four-stroke, single-cylinder, constant speed, and naturally aspirated research diesel engine with an eddy current dynamometer. Conventional transesterification process is carried out to convert the raw mahua oil into mahua oil biodiesel (BD100). Copper oxide (CuO) was chosen as a nanoparticle; the mass fraction of 100 ppm and the particle sizes of 10 and 20 nm were blended with mahua oil methyl ester using an ultrasonicator, and the physicochemical properties were measured. The physicochemical properties of BD100 and nanoparticle-included BD100 are at par with EN14214 limits. Brake-specific fuel consumption (BSFC) of BD100 is higher than that of diesel, and brake thermal efficiency (BTE) is lower than that of diesel (D100). The inclusion of 10-nm particle size of CuO nanoparticle in BD100 improves the BSFC and BTE by 1.3 and 0.7%, respectively, when compared with BD100. The CuO nanoparticle inclusion at 20-nm nanoparticle in biodiesel further improves the performance parameters than those at 10-nm nanoparticle. Further, the BD100 promotes a lower level of smoke emissions, carbon monoxide (CO), and hydrocarbon (HC) and with a prominent increase in oxides of nitrogen (NOₓ) emissions. The inclusion of 10-nm particle size of CuO nanoparticle in BD100 reduces the NOₓ, HC, CO, and smoke emission by 3.9, 5.6, 4.9, and 2.8%, respectively, at peak load condition when compared with BD100. The addition of CuO nanoparticle at 20-nm nanoparticle in biodiesel further reduces the NOₓ, HC, CO, and smoke emissions.
Show more [+] Less [-]Renewable energy, economic growth, human capital, and CO2 emission: an empirical analysis Full text
2019
Mahmood, Nasir | Wang, Zhaohua | Hassan, Syed Tauseef
This study contributes to the literature by estimating the interaction effects of economic growth and renewable energy consumption on carbon dioxide (CO₂) emissions with the inclusion of human capital. The interaction between economic growth and renewable energy consumption suggests how income level affects energy consumption and CO₂ emissions. The study applies three-stage least square and ridge regression methods with Pakistani data from 1980 to 2014. The empirical findings show that the interaction effect of income and renewable energy contributes to CO₂ emissions. Besides, trade openness also increases CO₂ emissions, while the human capital mitigates CO₂ emissions. Furthermore, the moderating effect of economic growth helps to form the environmental Kuznets curve (EKC) hypothesis in Pakistan.
Show more [+] Less [-]Assessment of individual and mixed toxicity of bromoform, tribromoacetic-acid and 2,4,6 tribromophenol, on the embryo-larval development of Paracentrotus lividus sea urchin Full text
2019
Lebaron, Karine | Mechiri, Lilia | Richard, Simone | Austruy, Annabelle | Boudenne, Jean-Luc | Coupé, Stéphane
Water chlorination is the most widely used technique to avoid microbial contamination and biofouling. Adding chlorine to bromide-rich waters leads to the rapid oxidation of bromide ions and leads to the formation of brominated disinfection by-products (bromo-DBPs) that exert adverse effects on various biological models. Bromo-DBPs are regularly encountered within industrialized embayments, potentially impacting marine organisms. Of these, bromoform, tribromoacetic acid and tribromophenol are among the most prevalent. In the present study, we tested the potential toxicity and genotoxicity of these disinfection by-products, using sea urchin, Paracentrotus lividus, embryos. We highlighted that tribromophenol showed higher toxicity compared to bromoform and tribromoacetic acid. Furthermore, a synergistic effect was detected when tested in combination. Pluteus cells exposed for 1 h to mixtures of DBPs at several concentrations demonstrated significant DNA damage. Finally, when compared to a non-exposed population, sea urchins living in a bromo-DPB-polluted area produced more resistant progenies, as if they were locally adapted. This hypothesis remains to be tested in order to better understand the obvious impact of complex bromo-DBPs environments on marine wildlife.
Show more [+] Less [-]The associations of air pollution exposure during pregnancy with fetal growth and anthropometric measurements at birth: a systematic review and meta-analysis Full text
2019
Fu, Li | Chen, Yi | Yang, Xinyi | Yang, Zuyao | Liu, Sha | Pei, Lei | Feng, Baixiang | Cao, Ganxiang | Liu, Xin | Lin, Hualiang | Li, Xing | Ye, Yufeng | Zhang, Bo | Sun, Jiufeng | Xu, Xiaojun | Liu, Tao | Ma, Wenjun
Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air pollution during pregnancy on fetal growth have been investigated using ultrasound in many previous studies, the results were inconsistent and disputable. We aimed to qualitatively and quantitatively investigate the associations of air pollution exposure during different periods of pregnancy with fetal growth and anthropometric measurements at birth. We searched for all studies investigating the associations of air pollution exposure during pregnancy with fetal growth and birth anthropometric measurements in English and Chinese databases published before July 31, 2017. A random-effects model was employed in the meta-analysis to estimate the pooled effects of each 10 μg/m³ increment in air pollutant exposure. The ACROBAT-NRSI tool was applied to assess the quality of each included study, and the GRADE tool was employed to assess the overall quality of the meta-analysis. Maternal PM₂.₅ exposure (10 μg/m³) during the entire pregnancy was negatively associated with head circumference at birth (β = − 0.30 cm, 95% CI − 0.49, − 0.10), and NO₂ exposure during the entire pregnancy was significantly linked to shorter length at birth (β = − 0.03 cm, 95% CI − 0.05, − 0.02). Maternal exposure to higher NO₂ and PM₂.₅ during pregnancy may impair neonatal head circumference and length development, respectively. More studies are needed to confirm the effects of NO₂ and PM₂.₅ and to identify the sources and major toxic components of PMs.
Show more [+] Less [-]Marine macro-algae attenuates nephrotoxicity and hepatotoxicity induced by cisplatin and acetaminophen in rats Full text
2019
Sohail, Nida | Hira, Khan | Tariq, Amna | Sultana, Viqar | Ehteshamul-Haque, Syed
Cisplatin is considered one of the best anticancer medications often used for the treatment of various cancers even with its adverse effects. Acetaminophen (paracetamol) is a widely used analgesic-antipyretic drug that causes hepatotoxicity at higher than the effective doses. The present study assesses the nephroprotective and hepatoprotective effects of two seaweeds against cisplatin and acetaminophen toxicity in rats. Damage to the liver and kidney was induced by administering a single intraperitoneal dose of acetaminophen (600 mg/kg) or cisplatin (7 mg/kg) to groups of rats. The damage to the liver and kidney was assessed by the elevated liver (ALT, AST, ALP, LDH, electrolytes) and kidney (urea, creatinine) biomarkers. The ethanol extract of brown seaweed reversed the elevated levels of kidney and liver biomarkers along with triglycerides, cholesterol, and glucose. Among the two seaweeds, Sargassum ilicifolium showed better nephroprotective and hepatoprotective effects than the standard drug N-Acetyl-cysteine, Halymenia porphyroides showed only limited protection. Findings of this study provide evidence of nephroprotective and hepatoprotective effects of S. ilicifolium. Seaweed could be a beneficial dietary supplement to attenuate nephrotoxicity and hepatotoxicity.
Show more [+] Less [-]Immobilization of hexavalent chromium in cement mortar: leaching properties and microstructures Full text
2019
Bakhshi, Nematollah | Sarrafi, Amir | Ramezanianpour, Ali Akbar
Stabilization and solidification (s/s) of heavy metals by cementitious materials are one of the effective methods in hazardous waste management. In cement alkaline environment, Cr(VI) compounds appear in the form of chromate anion (CrO₄⁻²), which is highly soluble; it makes the implication of the s/s method challenging. Therefore, it is important to study the amount of chromium leaching from cementitious materials. The effects of Cr(VI) concentration and water-to-cement (w/c) ratio on the level of leaching of chromium from cement mortar (CM) were investigated in this study. Results indicated w/c not significantly affect the leaching of chromium in the age of 28-day but in the 90-day-old samples indicated a reduction in leaching of chromium from mortar with increasing w/c. Results from toxicity characteristic leaching procedure (TCLP) tests indicated that the efficiency of Cr(VI) stabilization was reduced with greater chromium content but was enhanced with increased w/c. In detail, results showed that only about 0.21% and 0.26% cement weight in TCLP and tank test of Cr(VI) was stabilized in CM, respectively. The results of X-ray diffraction (XRD) and scanning electron microscope (SEM/EDS) tests indicated that increasing the Cr(VI) content leads to changes in the formation of the cement main phases and microstructure of CM.
Show more [+] Less [-]Chive (Allium schoenoprasum L.) response as a phytoextraction plant in cadmium-contaminated soils Full text
2019
Eisazadeh, Somayyeh | Asadi Kapourchal, Safoora | Homaee, Mehdi | Noorhosseini, Seyyed Ali | Damalas, Christos A.
Cadmium (Cd) soil contamination poses a major hazard to safe food production throughout the world, calling upon actions for decontamination using environmentally friendly methods, such as phytoextraction. In this study, the capability of chive (Allium schoenoprasum L.) for phytoextracting Cd from contaminated soils was tested. Growth of chive was studied in a soil spiked with 0, 15, 30, 60, and 120 mg Cd/kg soil, and then, concentrations of Cd in soil, plant shoots, and roots were measured after harvest. Chive dry matter production was not affected significantly by the different Cd levels in soil, except from the maximum Cd concentration (120 mg Cd/kg soil), where dry matter was reduced by 77%. Cadmium accumulation occurred mostly in roots rather than in shoots, with maximum Cd concentrations 482.48 and 26.65 mg/kg of dry matter, respectively. Translocation factor (the proportion of Cd concentration in the aerial plant parts to that in the roots) was below 1 in all contaminated levels and decreased with increasing Cd concentrations in soil, indicating low Cd reallocation from roots to shoots. Maximum amount of Cd absorption (Cd concentration in shoots), maximum contaminant uptake rate, and minimum clean-up time were all observed in Cd concentration 60 mg/kg soil. Based on chive potential to acquire Cd in its roots and shoots, it can be designated as a convenient species for reducing Cd from contaminated soils up to concentrations of 60 mg Cd/kg soil.
Show more [+] Less [-]Effect of a humic acid colloid on the sorption behaviour of Sr onto soil in a candidate high-level radioactive waste geological disposal site Full text
2019
Zuo, Rui | Chen, Minhua | Lin, Yuanhui | Yang, Jie | Jin, Shuhe | Yue, Weifeng | Wang, Jinsheng | Teng, Yanguo
We explored the effect of the presence or absence of humic acid (HA) on the sorption behaviour of Sr onto soil. We examined three different experimental cases for Sr sorption: (1) sorption in the presence of only colloidal HA, (2) sorption in the presence of only soil and (3) sorption in the presence of both colloidal HA and soil (HS). A batch technique was used to study the influencing factors, including the amount of colloidal HA, solid content, pH, initial concentration of Sr and contact time. The experiments showed that the influencing factors significantly affected the sorption process. For example, in the case of soil and HS, the sorption percentage increased rapidly with increasing solid content at m/V < 20 g/L, changing from 8.35% and 37.54% to 49.09% and 77.03%, respectively. Moreover, scanning electron microscopy and Fourier transform infrared spectroscopy were used to characterize samples. The kinetics and isotherms of Sr were best described by the pseudo-second-order and Langmuir models, which indicated that the process was controlled by chemisorption and uniform monolayer sorption with constant energy on the outer surface. These findings provide valuable information for predicting strontium migration in radioactive waste disposal sites.
Show more [+] Less [-]Microfibers: a preliminary discussion on their definition and sources Full text
2019
Liu, Jianli | Yang, Yunfei | Ding, Jiannan | Zhu, Bo | Gao, Weidong
Microfibers are a major component of microplastics and have been found nearly everywhere, especially in marine and freshwater habitats around the world. Therefore, microfibers have gained considerable attention in environmental science research. However, there is still no clear consensus on a definition that can encompass all necessary properties to describe microfibers as emerging pollutants. Therefore, we propose a definition for debate by taking the related descriptions of microplastics and textile fibers as references. Moreover, the potential sources from the perspectives of textile engineering, including production, use, care, and end-of-life disposal of fibrous materials, are discussed. For further investigation of microfiber pollution, the gap between current knowledge and major microfiber pollution concerns must be bridged.
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