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Soybean isoflavone ameliorates cognitive impairment, neuroinflammation, and amyloid β accumulation in a rat model of Alzheimer’s disease
2019
Essawy, Amina E. | Abdou, Heba Mohamed | Ibrahim, Hania M. | Bouthahab, Najya M.
Oxidative stress and neuroinflammatory changes appear to be the early events involved in AD’s development and progression. The present study was designed to assess the effect of soybean isoflavone extract (SIFE) against colchicine-induced cognitive dysfunction and oxidative stress in male rats.Fifty adult male Wistar albino rats were divided into five groups: control, ACSF-treated group, soybean isoflavones (SIF)-treated group, colchicine (COL)-treated group, and SIF + COL-treated group. We found that an intracerebroventricular (icv) injection of a single dose of colchicine (7.5 μg/rat bilaterally) resulted in learning deficits in rats subjected to the Morris water maze task associated with marked oxidative damage and decreased acetyl cholinesterase (AChE) activity. In addition, COL caused significant increase in amyloid beta peptide 1-42 (β, amyloid 1-42) interleukin-1β (IL-1β), tumor necrosis factor-α (TNFα), cyclooxygenase-2 (COX-2) and TNF-α genes expression in the brain, and glial fibrillary acidic protein (GFAP) in cortical astrocytes in the brain cortex.Treatment with SIFE (80 mg/kg b.wt) daily for 14 days followed by a single dose of COL significantly reduced the elevated oxidative stress parameters and restored the reduced antioxidant activities. Besides, the administration of SIFE reversed the overproduction of β, amyloid 1-42, pro-inflammatory cytokines, and GFAP in the brain. The obtained results were confirmed by histological observations that clearly indicate a neuroprotective effect of SIF against AD.
显示更多 [+] 显示较少 [-]Contributions of egg production and egg hatching to the total toxicity of teflubenzuron in Yuukianura szeptyckii (Collembola) in soil toxicity test
2019
Lee, Yun-Sik | Son, Jino | Wee, June | Kim, Yongeun | Kim, Du Yung | Kwon, Jung-Hwan | Cho, Kijong
In the standard ISO soil toxicity test using Collembola, adult survival and juvenile production are the only endpoints that can be attainable. The information on egg production and egg hatching cannot be investigated in the ISO test. To overcome this limitation, in this study, the effects of teflubenzuron on life history parameters of Yuukianura szeptyckii (Collembola) were investigated with a compressed soil test. Teflubenzuron is an insect growth regulator and has a negative effect on egg production, and egg hatching process of arthropods. LC₅₀ decreased with increases in exposure period from 6.97 mg/kg in the third week to 3.60 mg/kg in the fourth week. The EC₅₀ for egg and juvenile production was 0.57 mg/kg and 0.26 mg/kg, respectively. The hatching rate decreased significantly from 46 to 7% as the concentration increased from 0.25 to 1.00 mg/kg, respectively, and the molting frequency was significantly affected only at > 4 mg/kg. The toxic contribution rate (TCR) was defined as the ratio of juvenile production at an exposure concentration compared with the control, and a simple life history model was developed for TCR estimations. At the lower concentrations (< 0.3 mg/kg), the hatching rate reduction was a main contributor to the total toxicity, but the adult mortality and egg production reduction were the main contributors at the higher concentrations (> 2.0 mg/kg). The contribution of egg production reduction remained relatively constant. Since collembolan populations in the soil can be composed of various developmental stages, the differences in the sensitivity to chemicals depending on the developmental stages should be included in the assessment of the toxic impact on soil ecosystems.
显示更多 [+] 显示较少 [-]Degradation of naproxen in chlorination and UV/chlorine processes: kinetics and degradation products
2019
Liu, Yongze | Tang, Yuqing | Wu, Yongxin | Feng, Li | Zhang, Liqiu
Naproxen (NAP) is a nonsteroidal anti-inflammatory drug which has been widely used and frequently detected in water environments. This study investigated the NAP degradation in the chlorination and UV/chlorine disinfection processes, which usually acted as the last barriers for water treatment. The results showed that both chlorination and UV/chlorine disinfection could remove NAP effectively. At various chlorine dosages (0.1~0.5 mM), the contributions of chlorination and reactive radicals to the degradation of NAP in the UV/chlorine process were calculated to be 50.5~56.9% and 43.1~49.5%, respectively. However, the reactive radicals dominated in NAP degradation in alkaline solutions, while chlorination dominated in acidic conditions. The HCO₃⁻ (10~50 mM) slightly inhibited, Cl⁻ (10~50 mM) gradually promoted, and HA (1~5 mg/L) significantly reduced NAP degradation by UV/chlorine process. The degradation intermediates and products were obtained via high-performance liquid chromatography with QE-MS/MS; NAP was degraded by demethylation, acetylation, and dicarboxylic acid pathways during the chlorination and UV/chlorination processes.
显示更多 [+] 显示较少 [-]High NO and N2O accumulation during nitrite denitrification in lab-scale sequencing batch reactor: influencing factors and mechanism
2019
Wang, Sha | Zhao, Jianqiang | Huang, Ting
Nitrous oxide (N₂O) accumulation in biological nitrogen removal has drawn much attention in recent years; however, nitric oxide (NO) accumulation in denitrification was rarely studied. In this study, NO and N₂O accumulation during nitrite denitrification in a lab-scale sequencing batch reactor (SBR) were investigated. Results showed that low pH (< 7) and high influent loading (> 360:90) (COD:NO₂⁻-N) caused serious NO and N₂O accumulation. The maximal NO accumulation of 4.96 mg L⁻¹ was observed at influent loading of 720:180 and the maximal N₂O accumulation of 46.29 mg L⁻¹ was found at pH of 6. The NO accumulation was far higher than the values reported in previous studies. In addition, the high NO accumulation could completely inhibit the activities of reductases involved in denitrification. High NO and N₂O accumulation were mainly caused by significant free nitrous acid (FNA) and NO inhibition at low pH and high influent loading. There were significant differences on NO and N₂O accumulation at different carbon to nitrogen (COD/N). Low COD/N (≤ 4) could mitigate NO accumulation, but led to high N₂O accumulation. It is speculated that NO accumulation is related to the rapid denitrification with accumulated electron in anaerobic stage at high COD/N. N₂O accumulation is attributed to intense electron competition at low COD/N. High dissolved oxygen (DO) of 4.04 mg L⁻¹ was detected during NO detoxification in this experiment, which is speculated to be partly caused by NO dismutation.
显示更多 [+] 显示较少 [-]Multi-criteria of wind-solar site selection problem using a GIS-AHP-based approach with an application in Igdir Province/Turkey
2019
Koc, Ahmet | Turk, Seda | Şahin, Gökhan
Sustainable sources like wind, solar, and geothermal power are defined as a clean source of renewable energy which has a less harmful impact on the environment than other energy sources such as coal, natural gas and oil. Turkey is one of the energy-importing countries where air pollution has been become an inevitable environmental concern. Thus, investments on sustainable sources have been developed rapidly in recent years in Turkey. This paves the way for studying a site selection problem considering both solar and wind energy in Igdir Province located in the east part of Turkey. In the literature, there are many studies on solar-wind energy to select a desirable site for both energy sources, and many solution techniques have been proposed dealing with this problem. In this study, one of multi-criteria decision-making methods named analytical hierarchy process (AHP) and geographical information systems (GIS) are used to determine suitable site selection for solar-wind energy investigating four counties of Igdir: Tuzluca, Igdir Central, Karakoyunlu and Aralik. The aim of this work is first to investigate possible locations for solar-wind power plant installation using a mapping method, GIS, and then, AHP is applied to the problem to obtain optimum areas for both solar-wind energy. Also, more accurate results are provided comparing results of two methods, GIS and AHP. The results reveal that 524.5 km² for solar power plant and 147.2 km² for wind turbine are suitable while only 49.1 km² is suitable for solar-wind power plan installation.
显示更多 [+] 显示较少 [-]Blood and seminal plasma mercury levels and predatory fish intake in relation to low semen quality
2019
Ai, Chin-En | Li, Jingren | Tsou, Ming-Chien | Chen, Jun-Lin | Hsi, Hsing-Cheng | Chien, Ling-Chu
Declining human sperm quality has been demonstrated in several recent studies. Age, environmental factors, and nutritional factors can affect semen quality. Mercury (Hg) is considered a male reproductive toxicant. Animal studies indicated that exposure to Hg can cause DNA damage, sperm dysfunction, and decreased sperm motility. Some previous studies also revealed that blood Hg levels in infertile or subfertile males were higher than those in normal males. In this study, we recruited 84 male participants from a reproductive medical center and investigated the Hg, lead, and selenium levels in blood and seminal plasma. Participants were divided into two groups, low- and high-quality semen groups, according to the World Health Organization reference values for human semen characteristics. The distribution of blood reproductive hormones and information on participants’ lifestyle and medical history were collected from structured questionnaires. Average Hg levels in blood were 9.3±5.9 versus 8.9±5.9 and in seminal plasma were 1.26±0.61 versus 1.05±0.52 μg/L in the low- and high-quality semen groups, respectively. There was a dose-dependent relationship between blood Hg levels and normal sperm morphology (p=0.02). Participants with predatory fish intake and high blood Hg level had lower sperm with a normal morphology. Therefore, predatory fish intake may be a critical risk factor for elevated Hg levels in males and cause low semen quality.
显示更多 [+] 显示较少 [-]Renewable energy, economic growth, human capital, and CO2 emission: an empirical analysis
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.
显示更多 [+] 显示较少 [-]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
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.
显示更多 [+] 显示较少 [-]Distilled pyroligneous liquor obtained from Eucalyptus grandis and chitosan: physicochemical properties of the solution and films
2019
da Silva Porto, Fabiane Grecco | Campos, Ângela Diniz | Garcia, Irene Teresinha Santos
The pyroligneous liquor is a product obtained during the production of charcoal, with well-known antimicrobial activity. In this work, we characterized the physical chemistry properties of a formulation composed of distilled pyroligneous liquor (DPL), obtained from Eucalyptus grandis, and chitosan. A good interaction between the polymer and the solvent was observed. Auto-supported films were prepared with these systems and characterized with respect to their structure and photo-protection properties, water vapor permeability, and resistance to water and to thermal degradation. They present a semi-crystalline structure and are hygroscopic, but are stable under immersion for up to 7 days. The swelling degree in water is 300% in weight and the permeability to water vapor was between 30 and 45 g m⁻¹ h⁻¹ (for films with 80 to 10 μm, respectively). The obtained films are able to efficiently block the incident UVB and UVC radiation; the molar absorptivity decreases exponentially with increasing wavelength and is stable up to 300 °C. These properties confer desirable properties to the films, obtained from these precursors of a renewable source, to be used as coatings.
显示更多 [+] 显示较少 [-]Monitoring polychlorinated dibenzo-p-dioxins/dibenzofurans and dioxin-like polychlorinated biphenyls in Africa since the implementation of the Stockholm Convention—an overview
2019
Pius, Christina | Sichilongo, Kwenga | Koosaletse Mswela, Pulane | Dikinya, Oagile
Polychlorinated dibenzo-p-dioxin (PCDDs), polychlorinated dibenzofurans (PCDF), and dioxin-like polychlorinated biphenyl (dl-PCB) are groups of toxic compounds released into the environment as unintentional by-products of combustion. They persist, bioaccumulate through the food chain, and cause adverse health effects. This review attempts to collate available information on the release of PCDD/Fs and dl-PCBs and other critical data relevant to their monitoring in Africa during the existence of the Stockholm Convention (SC). Much as the implementation of the SC may be lagging, literature showed that there has been encouraging efforts that have been made with respect to PCDDs/Fs and dl-PCBs monitoring in Africa. Results from a global monitoring study showed that PCDD/Fs released to air in Africa stood at 18–532 fg WHO₉₈ TEQ/M³ while dl-PCBs were 7–278 fg WHO₉₈ TEQ/m³. In human milk, the total concentration of PCDD/Fs, i.e., WHO 2005 TEQ LB has been reported to range from 0.5 ng/g fat to 12 ng/g fat. Fourteen laboratories in Africa participated in inter-laboratory assessments of persistent organic pollutants (POPs) with two specifically for PCDD/Fs analysis. This shows that some efforts are being made to boost capacity in Africa. Levels of PCDDs/Fs and dl-PCBs in clay consumed by pregnant women have been reported in Cameroon, Democratic Republic of Congo (DRC), Nigeria, Zimbabwe, Ĉote d’Ivoire, and Uganda with a maximum concentration of 103 pg TEQ/g. This finding was very significant since women are the most impacted through exposure to POPs, a fact that is acknowledged by the SC.
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