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Protective effect of quercetin on rat testes against cadmium toxicity by alleviating oxidative stress and autophagy Texto completo
2020
Wang, Jicang | Zhu, Huali | Wang, Ke | Yang, Zijun | Liu, Zongping
Cadmium (Cd), a highly toxic heavy metal, adversely affects human and animal health. Quercetin (Que) is a kind of flavonoid that can protect many tissues from the toxic effect of heavy metals. Although many studies have explored the adverse effects of cadmium on rats and other animals, the mechanism of Cd-induced testicular autophagy and the antagonistic effect of Que on cadmium remain unclear. In this study, Sprague–Dawley rats were treated with Cd, Que or Cd, and Que supplements to explore the mechanisms of Que-alleviated testis injury caused by Cd exposure. The rat body weight and relative testicular weight were measured. Morphological changes in testes and indices of oxidative stress were also examined. The expression levels of autophagy-related genes were detected as well. Results showed that Cd decreased the rat body weight and relative testicular weight and induced pathological changes in testes. Conversely, Que alleviated these changes. We also found that Cd increased the malondialdehyde content and decreased the contents of total superoxide dismutase, glutathione peroxidase, catalase, and glutathione. Moreover, the protein expression levels of P62 and LC3-II increased under Cd exposure conditions. Conversely, Que obviously alleviated these toxic activities induced by Cd. Overall, this study showed that Cd accumulated in rat testes, leading to oxidative stress and autophagy. Que can reduce cadmium toxicity by reducing oxidative stress and inhibiting autophagy. The specific mechanism of Que antagonizing Cd toxicity can provide new insights into countering cadmium toxicity.
Mostrar más [+] Menos [-]The influence of processing and clarifier agents on the concentrations of potentially toxic elements (PTEs) in pekmez (a grape molasses-like syrup) Texto completo
2020
Heshmati, Ali | Ghadimi, Sabah | Ranjbar, Akram | Mousavi Khaneghah, Amin
The changes in some potentially toxic elements (PTEs) including lead (Pb), cadmium (Cd), arsenic (As), iron (Fe), zinc (Zn), and copper (Cu) during pekmez (grape molasses-like syrup) processing and the utilization of various types of clarifiers (white soil, bentonite, and gelatin) in two levels (1.5 and 3% w/w) were analyzed. The average concentrations of Pb, Cd, As, Fe, Zn, and Cu in grape samples were measured as 0.055 ± 0.005, 0.030 ± 0.002, 0.044 ± 0.002, 2.882 ± 0.013, 2.372 ± 0.088, and 1.194 ± 0.01 μg g⁻¹. During pekmez production, the range of changes in Pb, Cd, As, Fe, Zn, and Cu was −43.38% to 40.25%, −55.49% to 0.23%, −76.15% to 1.80%, −74.15% to 58.47%, −40.55% to −18.12%, and −83.16% to −21.39%, respectively. The effect of the clarification process on the PTEs depended on the type and concentration of both PTE and clarifier agent used while the incorporation of gelatin resulted in a significant reduction in all of PT. Graphical abstract
Mostrar más [+] Menos [-]Association of intronic polymorphisms (rs1549339, rs13402242) and mRNA expression variations in PSMD1 gene in arsenic-exposed workers Texto completo
2020
Ahmad, Saqiba | Arif, Bushra | Akram, Zertashia | Ahmed, Malik Waqar | K̲h̲ān, Asadullāh | Hussain, Muhammad Zahid | Rahman, Faisal | Kayani, Mahmood Akhtar | Mahjabeen, Ishrat
Ubiquitin-proteasome system (UPS) gene, PSMD1, is an important gene for neutralization of damaged and misfolded protein(s). The current study was designed to study the genetic and expression variations of PSMD1 gene as a consequence of arsenic exposure and its potential implications in arsenic induced diseases. In the present study, 250 blood samples of exposed industrial workers along with 250 controls were used. Initially, tetra amplification refractory mutation system-PCR was used to determine the role of PSMD1 gene polymorphisms (rs1549339, rs13402242) in industrial workers and controls. Frequency of homozygous mutant genotype of rs1549339 (OR: 2.23, 95% CI: 1.51–3.32, p = 0.0001) and rs13402242 (OR: 2.96, 95% CI: 1.52–5.75, p = 0.001) was observed significantly higher in exposed individuals vs controls. Secondly, qPCR was performed for expression analysis of PSMD1 gene. Significant down-regulated expression of PSMD1 gene (p < 0.0001) was observed vs controls, and this down-regulation was observed more pronounced in smokers (p < 0.0001) with maximum exposure duration (p < 0.0008). This down-regulated expression was observed significantly more pronounced in welding (p < 0.004) and brick kiln industries (p < 0.04) compared to other selected industries. The obtained results suggest that the exposure to arsenic may have an increased risk of developing disease(s) because of arsenic-induced PSMD1 variations.
Mostrar más [+] Menos [-]An imazethapyr-based herbicide formulation induces genotoxic, biochemical, and individual organizational effects in Leptodactylus latinasus tadpoles (Anura: Leptodactylidae) Texto completo
2020
Pérez-Iglesias, Juan M. | Brodeur, Julie C. | Larramendy, Marcelo L.
Genotoxic, biochemical, and individual organizational effects on Leptodactylus latinasus tadpoles were evaluated after exposure to an imazethapyr (IMZT)-based commercial herbicide formulation, Pivot® H (10.59% IMZT). A determination of the value of the lethal concentration (LC50) was determined as a toxicological endpoint. Alterations in animal behavior and morphological abnormalities as well as cholinesterase (ChE), catalase (CAT), and glutathione S-transferase (GST) activities were employed as individual sublethal endpoints. Micronuclei frequencies (MNs), binucleated cells (BNs), blebbed nuclei (BLs), lobed nuclei (LBs), notched nuclei (NTs), erythroplastids (EPs), and evaluation of DNA strand breaks were employed as genotoxic endpoints. All biomarkers were evaluated after 48 and 96 h of exposure to concentrations of IMZT within 0.07–4.89 mg/L. LC50₉₆ₕ values of 1.01 and 0.29 mg/L IMZT were obtained for Gosner stages 25 and 36, respectively. Irregular swimming, diamond body shape, and decreased frequency of keratodonts were detected at both sampling times. Results showed that IMZT increased GST activity and MN frequency at 48 and 96 h of exposure. Other nuclear abnormalities were also observed in the circulating erythrocytes of tadpoles, i.e., NT and BL values after 48 h, and LN, BL, and EP values after 96 h. Finally, results showed that IMZT within 0.07–0.22 mg/L increased the genetic damage index in tadpoles exposed for both exposure times (48 and 96 h). This study is the first to report the sublethal biochemical effects of IMZT in anurans and is also the first report using L. latinasus tadpoles as a bioindicator for ecotoxicological studies.
Mostrar más [+] Menos [-]Biology, ecology and management of Raphanus raphanistrum L.: a noxious agricultural and environmental weed Texto completo
2020
Kebaso, Lynda | Frimpong, David | Iqbal, Nadeem | Bajwa, Ali Ahsan | Namubiru, Halima | Ali, Hafiz Haider | Ramiz, Zarka | Hashim, Saima | Manalil, Sudheesh | Chauhan, Bhagirath Singh
Weeds are a major constraint to crop production and a barrier to human efforts to meet the ever-rising global demand for food, fibre and fuel. Managing weeds solely with herbicides is unsustainable due to the rapid evolution of herbicide-resistant weeds. Precise knowledge of the ecology and biology of weeds is of utmost importance to determine the most appropriate nonchemical management techniques. Raphanus raphanistrum L. is an extremely invasive and noxious weed due to its prolific seed production, allelopathic potential, multiple herbicide resistance and biological potential. R. raphanistrum causes high crop yield losses and thus has become one of the most troublesome agricultural and environmental weeds. R. raphanistrum could exchange pollen with herbicide-tolerant canola and could become an environmental threat. This weed has evolved resistance to many herbicides, and relying exclusively on herbicide-based management could lead to severe crop loss and uneconomical cropping. Although reviews are available on the ecology and biology of R. raphanistrum, significant changes in tillage, weed management and agronomic practices have been occurring worldwide. Therefore, it is timely to review the status of noxious weeds in different agro-ecological zones and management scenarios. This review focuses on the response of R. raphanistrum to different cultural, mechanical, biological, chemical and integrated management strategies practiced in various agro-ecosystems, and its biological potential to thrive under different weed management tactics. In addition, this review facilitates a better understanding of R. raphanistrum and describes how weed management outcomes could be improved through exploiting the biology and ecology of the weed.
Mostrar más [+] Menos [-]Future trends and guidance for the triple bottom line and sustainability: a data driven bibliometric analysis Texto completo
2020
Tseng, Ming-Lang | Chang, Chia-Hao | Lin, Chun-Wei Remen | Wu, Kuo-Jui | Chen, Qing | Xia, Li | Xue, Bing
This study conducts a comprehensive literature review of articles on the triple bottom line (TBL) published from January 1997 to September 2018 to provide significant insights and support to guide further discussion. There were three booms in TBL publications, occurring in 2003, 2011, and 2015, and many articles attempt to address the issue of sustainability by employing the TBL. This literature analysis includes 720, 132, and 58 articles from the Web of Science (WOS), Inspec, and Scopus databases, respectively, and reveals the gaps in existing research. To discover the barriers and points of overlap, these articles are categorized into six aspects of the TBL: economic, environmental, social, operations, technology, and engineering. Examining the top 3 journals in terms of published articles on each aspect reveals the research trends and gaps. The findings provide solid evidence confirming the argument that the TBL as currently defined is insufficient to cover the entire concept of sustainability. The social and engineering aspects still require more discussion to support the linkage of the TBL and to reinforce its theoretical basis. Additionally, to discover the gaps in the data sources, theories applied, methods adopted, and types of contributions, this article summarizes 82 highly cited articles covering each aspect. This article offers theoretical insights by identifying the top contributing countries, institutions, authors, keyword networks, and authorship networks to encourage scholars to push the current discussion further forward, and it provides practical insights to bridge the gap between theory and practice for enhancing the efficiency and effectiveness of improvements.
Mostrar más [+] Menos [-]Phthalate esters (PAEs) in soil and vegetables in solar greenhouses irrigated with reclaimed water Texto completo
2020
Li, Yan | Huang, Guanhua | Zhang, Lei | Gu, Hua | Lou, Chunhua | Zhang, Hang | Liu, Honglu
Phthalate esters (PAEs) in environments have become a public concern due to their harmful impacts on human and environments, and waste/reclaimed water irrigation maybe one of their sources in agricultural soil. A field experiment was setup to analyze the impacts of reclaimed water irrigation on levels of PAEs in vegetables and topsoil in solar greenhouse on the North China Plain during 2015 and 2016. There were 6 varieties of vegetables. For each variety, there were three irrigation treatments, including groundwater irrigation, reclaimed water irrigation, and alternative irrigation with groundwater and reclaimed water (1:1, v/v). The results show that the levels of the 6 PAEs in soil and vegetables varied between 0.73 and 9.48 mg/kg and 1.89 and 6.35 mg/kg, respectively. There were no significant differences for PAE concentrations among these different treatments at each vegetable harvest (p > 0.05). For both soil and vegetable samples, Di-n-butyl phthalate (DnBP) and Di (2-ethylhexyl) phthalate (DEHP) were the most dominant PAEs, with contents of 0.39–4.43 mg/kg and 0.25–6.31 mg/kg, respectively, contributing12.5–74.60% and 21.24–76.48% of the total 6 PAEs, respectively. The contents of DnBP and dimethyl phthalate (DMP) in topsoil were higher than the suggested allowable values, while the concentration of each individual PAE in topsoil was lower than the suggested cleanup objectives. The levels of 6 PAEs, DEHP, and DnBP in vegetables were below the reference doses. The yields of eggplant, cauliflower, bean, cabbage, cucumber, and carrot were 64.4–67.0 t/ha, 10.9–13.0 t/ha, 12.3–15.1 t/ha, 17.3–17.5 t/ha, 43.9–44.5 t/ha, and 19.0–22.9 t/ha, respectively, and no significant differences were found among these different treatments for each kind of vegetable. The bioaccumulation factors (BCFs) of 6 PAEs in vegetable samples were 0.43–5.79 and the corresponding values for each PAE were 0.00–27.32, respectively. The BCFs of butyl benzyl phthalate were the greatest (with a mean of 9.28), followed by DEHP (with a mean of 3.03) and DMP (with a mean of 1.90). In one word, the reclaimed water in this study did not affect the vegetable yields obviously. PAE levels in soil and vegetables irrigated with reclaimed water were in the acceptable range. Considering the difference of reclaimed water quality of Sewage Treatment Plants in different areas, so more reclaimed water from different areas is needed to assess the impacts of reclaimed water irrigation on PAE contamination in soil and vegetables.
Mostrar más [+] Menos [-]Assessing environmental impacts of large centralized wastewater treatment plants with combined or separate sewer systems in dry/wet seasons by using LCA Texto completo
2020
Rashid, Siti Safirah | Liu, Yong-Qiang
Rainfall can affect influent flow rate and compositions of wastewater, and thus further affect wastewater treatment performance and the effluent quality. This study aims to study the influence of rainfall on the environmental impacts of centralized wastewater treatment plants. The correlations between rainfall, and influent flow rate and compositions of wastewater in wet and dry seasons with two sewer systems, i.e. combined and separate sewer systems, were primarily established. Environmental impacts were assessed with life cycle assessment (LCA) to understand the temporal environmental burdens in wet and dry seasons. Functional units as per m³ treated wastewater (FU1) and as per kg PO₄³-eq. removed (FU2), respectively, were used to evaluate impacts of wastewater treatment to the environment. Strong correlation between rainfall and the influent flow rate was found in the wastewater treatment plants with either a combined sewer system (with Pearson correlation coefficient r at 0.66) or a separate sewer system (with r at 0.84), where r represents the strength of the association between two variables. The rainfall effect is more obvious on the eutrophication potential and global warming potential than on other environmental indicators while sewer system, i.e. combined or separate, seems not important in the two cases studied. Both wastewater treatment plants (WWTPs) show a lower environmental burden in the wet season than in the dry season partially due to the dilution of wastewater by using FU1. The WWTP receiving high strength wastewater, however, demonstrates higher environmental impacts in the wet season by using FU2 than FU1, due to the less efficient treatment caused by heavy rainfall. Meanwhile, it is found that environmental impacts from the WWTP receiving low strength wastewater have no difference when using either FU1 or FU2. The results indicate that the environmental burdens particularly eutrophication and global warming caused by WWTPs are dependent on the correlations of rainfall intensity with wastewater quantity and quality instead of combined or separate sewer system. This could be used to guide a stricter control of eutrophication in a more sensitive season in more vulnerable receiving waters.
Mostrar más [+] Menos [-]Energy, exergy, environmental, and economic analysis of natural and forced cooling of solar still with porous media Texto completo
2020
Hassan, Hamdy | Yousef, Mohamed S. | Ahmed, M Salem | Fathy, Mohamed
The performance of single slope solar still with an enhanced condenser at different saline water mediums in the basin is studied and assessed based on productivity, energy, exergy, economic, and enviroeconomic methodologies. Six solar still configurations are considered: conventional solar still (CSS); modified solar still (MSS) which is a still with heat sink condenser; MSS having an umbrella (MSS + U); MSS with forced-air cooling (MSS + FA); MSS with forced-water cooling (MSS + FW); and finally, MSS with forced-water cooling and contains sand in the basin (MSS + FW + SD). Experiments are conducted under hot and cold climate conditions of Sohag city, Egypt. The results indicate that the MSS + FW + SD has a maximum daily yield of 5.37 kg/m² in summer and 2.74 kg/m² in winter with an increase of 36% in summer and 26% in winter compared with CSS. It was found that the maximum increase of the energy and exergy efficiency compared with CSS is achieved in the case of MSS + FW + SD of 39% and 33%, respectively. Furthermore, the maximum and minimum cost of freshwater is achieved in cases of MSS + U and MSS + FW + SD, respectively. Finally, among all studied systems, MSS + FW + SD achieves the best performance based on the exergoeconomic approach.
Mostrar más [+] Menos [-]Effects of nitrite graded doses on hepatotoxicity and nephrotoxicity, histopathological alterations, and activation of apoptosis in adult rats Texto completo
2020
El-Nabarawy, Nagla A. | Gouda, Ahmed S. | Khattab, Mohamed A. | Rashed, Laila A.
Nitrites are found in several forms; they are widely found in water resources and used as additives and preservatives for food and as a color source. We investigated the hazardous effects of exposing rats to different doses of nitrites. Moreover, we examined such impacts, after acute ingestion, on liver and renal tissues in rats and to what extent this affects the organs’ functions. Animals were divided into five groups: one control group 1 (group C) and four sodium nitrite (NaNO₂)–treated group (8 rats per group). The four NaNO₂-treated groups include group 2 (N20), group 3 (N40), group 4 (N60), and group 5 (N75). NaNO₂ was dissolved in distilled water, and single acute dose was orally given by gavage at 20, 40, 60, and 75 mg/kg body weight, respectively. Our results revealed significant increase of liver enzymes activity—aspartate transaminase (AST), alanine aminotransferase (ALT), and creatinine between different groups with increasing doses of nitrite ingestion. The results of hepatic and renal oxidative stress showed significant increase in the malondialdehyde (MDA) levels and significant decrease in the antioxidant parameters, such as reduced glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT), as the dose of nitrite increases. Further, the methemoglobin percent showed significant increase with increasing nitrite doses. Abnormal morphological alterations in the liver and kidney tissues were obviously proportional to the administered nitrite doses. The expression of caspase 3 and Bax level showed enhanced induction of immunoexpression, especially in the high doses of nitrites. On the other hand, the maximal immunoexpression level of anti-apoptotic marker Bcl₂ was found in lower doses of nitrites, whereas marked decrease of Bcl₂ levels was observed in the higher doses. In conclusion, administration of sodium nitrite in a dose-dependent manner is capable of inducing cellular and genetic toxicities and causes disturbance in biochemical analysis, oxidative and anti-oxidative balance, and methemoglobinemia. It also makes histopathological alterations and leads to the activation of apoptosis-related Bax, Bcl₂, and caspase 3 genes of liver and kidney tissues in rats.
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