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Fine particulate matter alters the microecology of the murine respiratory tract Texte intégral
2019
Yang, Biao | Zhang, Yu | Li, Bingyu | Zou, Yang | Xiao, Chunling
Fine particulate matter is a global challenge to human health. We investigated the effects and potential mechanisms of fine particulate matter on respiratory tract microecology in a lung injury mouse model. BALB/c mice were randomized into exposed and control groups. We found that the levels of soluble tumor necrosis factor receptor I was increased following the PM2.5 exposure. 16S rRNA sequencing of respiratory tract lavage fluid confirmed that the composition of the respiratory tract microecology was altered by the exposure. Lactobacillus was the most abundant of bacterial species present. Collectively, these results establish a link between exposure to fine particulate matter and alterations to the respiratory tract microecology. Elucidation of the underlying mechanisms may lead to treatment strategies in lung injury.
Afficher plus [+] Moins [-]Comparative evaluation of ultrafiltration and dynamic membranes in an aerobic membrane bioreactor for municipal wastewater treatment Texte intégral
2019
Isik, Onur | Abdelrahman, Amr Mustafa | Ozgun, Hale | Ersahin, Mustafa Evren | Demir, Ibrahim | Koyuncu, Ismail
This study investigated the applicability of self-forming hollow fiber dynamic membrane (DM) as a low-cost alternative to ultrafiltration (UF) membrane. A hollow fiber polyester fabric was used as a support material to form the DM layer. Submerged DM and UF hollow fiber membrane were placed in the same reactor in order to compare the treatment and filtration performance of each membrane. Morphological analyses were also carried out for DM surface. The system was operated continuously at a flux of 5 L/m² h for 85 days. High COD removal efficiency and total suspended solids (TSS) rejection were achieved by the DM. Transmembrane pressure (TMP) of the DM was higher in comparison to the UF membrane, which was related with the formation of cake layer in DM. DM technology can be used as an alternative to UF membrane for municipal wastewater treatment.
Afficher plus [+] Moins [-]Comparative assessment of the effects of meso-2,3-dimercaptosuccinic acid and salinomycin on spleen function of cadmium-exposed mice Texte intégral
2019
Kamenova, Kalina | Gluhcheva, Yordanka | Dorkov, Petar | Ivanova, Juliana
In this study, we present experimental data on the effects of meso-2,3-dimercaptosuccinic acid (DMSA) and tetraethylammonium salt of salinomycinic acid (Sal) on cadmium-induced spleen dysfunction and altered essential metal balance in mice. Sixty-day-old male mice (ICR line) were randomly divided into four groups: untreated control group (Ctrl)—obtained distilled water for 28 days, toxic control group (Cd)—exposed to cadmium acetate dihydrate at average daily dose of 20mg/kg body weight (BW) for 14 days, Cd + DMSA group—obtained cadmium acetate dihydrate as the toxic control group followed by treatment with 20mg/kg BW DMSA for 2 weeks, and Cd + Sal group—mice exposed to cadmium acetate dihydrate at average daily dose of 20mg/kg BW for 2 weeks followed by administration of Sal at an average daily dose of 20mg/kg BW for 2 weeks. The compounds were administered orally via the drinking water of the animals. We found that cadmium exposure caused splenomegaly and reduced the hemoglobin and hematocrit levels and total red blood cell count compared with untreated controls. Cadmium intoxication of mice induced accumulation of the toxic metal ion in the blood and spleen. Alterations in the endogenous levels of calcium (Ca) and iron (Fe) in the spleen of cadmium-exposed mice compared with those in untreated controls were observed. Treatment of cadmium-exposed mice with DMSA or Sal recovered the spleen weight and hematological parameters to normal control values, decreased cadmium concentration in the blood and spleen, and improved splenic architecture. The results prove that Sal is a potential antidote for treatment of Cd-induced spleen dysfunction.
Afficher plus [+] Moins [-]Assessing young consumers’ awareness and participation in sustainable e-waste management practices: a survey study in Northwest China Texte intégral
2019
Ramzan, Sidra | Liu, ChenGuang | Munir, Hina | Xu, Yan
The massive generation of electronic waste (e-waste) and the informal recycling of e-waste are serious concerns in China. As a hazardous waste stream, e-waste calls for sustainable management practices to avoid adverse effects on environment and health. However, consumers’ awareness and active participation are needed to make e-waste management successful. Therefore, this study is an exploratory attempt to investigate young consumer awareness, knowledge, and participation in sustainable e-waste management practices. Meanwhile, the study reviews the current situation of e-waste recycling, its related legislative framework, and practices in China. The survey revealed that the respondents have keen environmental consciousness, while they have low awareness about e-waste-related rules and regulations, recycling programs, and the formal and informal recycling sector. The findings provide valuable insights for practitioners in order to promote environmental awareness and sustainable e-waste management practices among young consumers in China.
Afficher plus [+] Moins [-]Review on the determination and distribution patterns of a widespread contaminant artificial sweetener in the environment Texte intégral
2019
Luo, Jingyang | Wu, Lijuan | Zhang, Qin | Wu, Yang | Fang, Fang | Feng, Qian | Li, Chao | Xue, Zhaoxia | Cao, Jiashun
The accurate determination of widespread artificial sweeteners (ASs) and the information of their distributions in environments are of significance to investigate the environmental behaviors. This paper firstly reviews the typical analytic methodologies for ASs and the main influencing factors during the analytic processes. Solid-phase extraction (SPE) with LC-ESI-MS is currently the leading-edge method. However, the efficiency and accuracy for ASs analysis in environmental samples are also dependent on the SPE cartridges, buffers and pH, matrix effects, and sample stability. A basic procedure for ASs determination in different environmental samples is proposed. The current occurrences of ASs in environments are then evaluated. The ASs, especially the acesulfame and sucralose, are widely detected in various environmental medium. The concentrations of investigated ASs are generally in the order of wastewater treatment plants (WWTPs) influent > WWTPs effluent > surface water > groundwater > drinking water; and atmosphere > soil. The ASs levels in the environment exhibit significant differences among different regions. Further analysis indicates that the phenomenon is highly correlated with the consumption patterns and the removal efficiency of WWTPs in a specific country.
Afficher plus [+] Moins [-]Effect of NaCl on nitrification performance and extracellular polymeric substance characteristic of Klebsiella sp. TN-10 Texte intégral
2019
Li, Dan | Jin, Yao | Huang, Jun | Wu, Chongde
Klebsiella sp. TN-10, isolated from tannery wastewater, exhibited excellent nitrification ability cultivated in media with NaCl contents ranging from 0 to 35 g/L. Analysis of antioxidative enzyme activities of TN-10 stressed by NaCl showed that the stain produced more superoxide dismutase (SOD) and catalase (CAT) to fight against salt stress conditions. Moreover, the auto-aggregation index of TN-10 decreased with the increment of NaCl contents, which is consistent with results of zeta potentials. Extinction-emission matrix (EEM) and Fourier-transform infrared (FT-IR) spectrum analyses showed that the compositions of extracellular polymeric substances (EPS) by TN-10 after NaCl shock were similar. Furthermore, proteins and polysaccharides were the main components of EPS, and the contents were greatly influenced by salinity. Then, circular dichroism (CD) spectrum was used to calculate the contents of each protein secondary structure. These results provided further insights into the knowledge of nitrification characteristics, auto-aggregation performance, and EPS compositions of TN-10 during NaCl shock.
Afficher plus [+] Moins [-]Use of biogas solid residue from anaerobic digestion as an effective amendment to remediate Cr(VI)-contaminated soils Texte intégral
2019
Song, Zilin | Fang, Linchuan | Wang, Jie | Zhang, Chao
Chromium (Cr) is one of the most common metal pollutants and has thus attracted considerable attention. In this study, we investigated the potential use of biogas solid residue (BSR) from anaerobic digestion as an effective amendment to decrease the bioavailability of Cr in Cr(VI)-polluted soil using pot experiments. Compared to the no-addition treatment, the addition of BSR (treatments—50, 100, and 150 g kg⁻¹ soil) increased the soil nutrient levels, microbial diversity and activities, and decreased the redox potential (Eh). BSR treatment of Cr(VI)-contaminated soil caused a reduction in soil Cr(VI) concentration (16.6–52.1%) and the exchangeable Cr proportion (15.2–52.4%), thereby decreasing the available Cr for uptake by plants. BSR treatments resulted in a reduction in the Cr contents of the roots and aboveground biomass of pakchoi plants. The Cr(VI) content in treated soils decreased with increasing BSR addition, with 150 g kg⁻¹ being the most efficient application. The relative abundance of Cr-reducing groups, such as Pseudomonas, Microbacterium, and Bacillus, increased with the increase in BSR application. The enhancement of soil Cr(VI) immobilization by the addition of the BSR was mostly attributed to the simultaneous effect of organic matter addition, stimulation of microorganisms, and reduced Eh value. Organic matter contributed more to the variation in Cr. The presence of BSR decreased the bioavailability of Cr in the soil and, therefore, lowered the potential mobilization of Cr(VI) from the soils. Our results demonstrated that BSR application may offer a potentially promising solution for enhancing agricultural production in Cr-contaminated soils.
Afficher plus [+] Moins [-]Levels, profiles, and emission characteristics of chlorobenzenes in ash samples from some industrial thermal facilities in northern Vietnam Texte intégral
2019
Nguyen, Hue Thi | Nguyen, Thu Thuy Thi | Tung, Nguyen Hoang | Hoang, Anh Quoc | Pham, Long Hai | Minh, Tu Binh
Chlorobenzenes (CBzs) are unintentionally produced organic contaminants from different thermal industrial processes, which have been scarcely surveyed in Asian developing countries including Vietnam. In this study, residue concentrations, profiles, emission factors, and annual emissions of seven chlorobenzene compounds were investigated in fly ash and bottom ash samples of some industrial facilities including brick making plant, steel and zinc production plants, and industrial and municipal waste incinerators in northern Vietnam. Total concentrations of seven CBzs in the ash samples were generally decreased in the order: industrial waste incinerator > municipal waste incinerator > steel-making plant > brick making plant. Emission pattern of CBzs varied considerably among different industrial plants, with 1,2- and 1,3-dichloro-, 1,2,3,4-tetrachloro-, and hexachlorobenzene as predominant compounds in the industrial waste incinerators and steel-making plants. Emission factors of CBzs estimated for the fly ash and bottom ash samples were in the range of 118–2020 and 5.3–22,600 μg ton⁻¹, respectively. Average annual emissions (AEs) of total seven CBzs estimated for fly ash and bottom ash in the investigated plants were in the range of 154–54,300 and 20,160–161,400 mg year⁻¹, respectively. The AEs of CBzs estimated for fly ash in the steel-making plant were higher than those in the waste incinerators. Meanwhile, CBz emissions for bottom ash were the highest in the steel-making plant, followed by the industrial and municipal waste incinerators. This is among the first studies on the emission characteristics of both low and highly chlorinated benzenes from industrial activities in Vietnam.
Afficher plus [+] Moins [-]Protective effect of cinnamon against acetaminophen-mediated cellular damage and apoptosis in renal tissue Texte intégral
2019
Abdeen, Ahmed | Abdelkader, Afaf | Abdo, Mohamed | Wareth, Gamal | Aboubakr, Mohamed | Aleya, Lotfi | Abdel-Daim, Mohamed
Acetaminophen, APAP, is a common over-the-counter drug with antipyretic-analgesic action. When APAP is used in large doses, it causes hepatotoxicity and nephrotoxicity but safe at therapeutic doses. Cinnamon (Cinnamomum zeylanicum) is extensively used in folk medicine due to its high content of natural antioxidants. The current investigation was planned to study the possible ameliorative effect of cinnamon toward induced APAP-apoptosis and cellular damage in renal cells. Four groups (nine rats each) were used; negative control group administrated distilled water for 15 days; positive control APAP group administrated a single dose of APAP (1 g/kg) orally on the last day; APAP+Cin L (200 mg/kg) and APAP+Cin H (400 mg/kg) aqueous extract of cinnamon orally once a day for 15 days. An hour after the last dose of cinnamon, all rats in the third and fourth group were administrated a single dose of APAP (1 g/kg) orally. GC/MS analysis was performed to identify the plant used in the study. APAP markedly increased serum levels of creatinine, BUN, and glucose and decreased levels of albumin and total protein. In addition, APAP could also exert severe alteration in the kidney histopathology along with upregulation of caspase-3 and PCNA. However, pre-treatment with cinnamon ameliorated the APAP-induced cellular alterations and apoptosis, possibly through its high content of antioxidants.
Afficher plus [+] Moins [-]Differential responses of growth, photosynthesis, oxidative stress, metals accumulation and NRAMP genes in contrasting Ricinus communis genotypes under arsenic stress Texte intégral
2019
Singh, Rajani | Jha, Ambuj Bhushan | Misra, Amarendra Narayan | Sharma, Pallavi
Effect of arsenate [As(V)] on biomass, photosynthetic rate, stomatal conductance, transpiration, oxidative stress, accumulation of As, Fe, Zn, Cu and Mn and expression of NRAMP genes was investigated in As(V) tolerant and sensitive genotypes of bioenergy crop Ricinus communis. As(V) treatments (100 and 200 μM) led to significant reduction in root and leaf biomass, photosynthetic rate, stomatal conductance and transpiration in GCH 2 and GCH 4 genotypes but no significant change or increase was observed in WM and DCH 177 genotypes. No significant difference was observed in hydrogen peroxide content and lipid peroxidation in As(V)-treated tolerant genotypes compared to control, whereas these parameters enhanced significantly in As(V)-treated sensitive genotypes. GCH 2 accumulated around two times As in leaves and showed significant reduction in concentration of Zn and Mn in the leaves and roots due to 200 μM As(V) treatment compared to WM. NRAMP genes are critical for uptake and distribution of essential divalent metal cations, photosynthesis and controlled production of reactive oxygen species in plants. RcNRAMP2, RcNRAMP3 and RcNRAMP5 genes showed differential expression in response to 200 μM As(V) in GCH 2 and WM suggesting that NRAMP genes are associated with differential responses of WM and GCH 2 genotypes to As(V) stress.
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