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Mucociliary transport, differential white blood cells, and cyto-genotoxicity in peripheral erythrocytes in fish from a polluted urban pond Texte intégral
2018
da Silva, EdisonBezerra | da Silva Corrêa, SandraAparecida | de Souza Abessa, DenisMoledo | da Silva, BrunoFerreira Xavier | Rivero, DoloresHelena Rodriguez Ferreira | Seriani, Robson
The present study evaluated the water quality of a polluted pond through the analysis of in vitro mucociliary transport, hematological parameters, and biomarkers of cyto-genotoxicity in the Nile tilapia (Oreochromis niloticus). Blood and mucus samples were collected from ten specimens from the polluted pond and from ten specimens from a control area. The fish were anesthetized with 3% benzocaine, mucus was collected directly from the gills, and blood was drawn from the caudal artery. Blood smears were stained using the May-Grünwald Giemsa process for the differential leukocyte counts and to determine the frequency of leukocytes, thrombocytes, erythroblasts, micronuclei, and nuclear abnormalities. The results revealed low transportability in vitro, a high percentage of monocytes and eosinophils, and increased frequency of leukocytes and nuclear abnormalities in fish from the polluted pond. However, the frequency of thrombocytes and erythroblasts and the percentage of lymphocytes and neutrophils were significantly lower. It is possible to conclude that changes in fish are due to poor water quality and that these non-destructive biomarkers can be used for the biomonitoring of aquatic environments vulnerable to contamination.
Afficher plus [+] Moins [-]Assessing watercourse quality: challenges in implementing European and Swiss legal frameworks Texte intégral
2018
Milano, Marianne | Chèvre, Nathalie | Reynard, Emmanuel
Hydro-climatic changes and the increasing release of pollutants into rivers by human activities tend to affect the quality of watercourses, to alter aquatic ecosystems and to reduce the amount of useable water. The ecological and chemical states of rivers and their evolution is thus of growing concern. In Europe and Switzerland, water policies are progressively shifting towards a holistic approach of river systems. The European Commission notably established a framework to highlight rivers’ ecological deficits and to enhance regional or local water management plans. In Switzerland, a similar framework is currently under development. In this paper, both procedures are compared and implemented in a Swiss catchment dominated by agricultural activities. The aim is to define the challenges that still need to be addressed to assess and sustain river health. The hydromorphological, ecological, and ecotoxicological quality of the river was evaluated. Both frameworks highlighted the fact that no section of the river can currently be classified as being in a good environmental state and that the state deteriorates as tributaries and wastewater discharge flow into the main riverbed. Chemical issues and water quality changes due to hydro-climatic variations and management strategies were also pinpointed. Both frameworks are thus useful tools to survey changes in rivers quality in space and over time. However, challenges remain regarding the appropriate strategies to monitor and analyze chemicals, the definition of target values and conditions, the evaluation and integration of human-induced pressures, and the overall evaluation of the state of a river. The development of integrated indicators or of ecosystem services approaches is considered as a potential solution to explore river health and to define efficient restoration measures by water managers.
Afficher plus [+] Moins [-]Release and kinetics of arsenic and plumbum in the Songhua River surficial sediments Texte intégral
2018
Liu, Guang-Min | An, Qing | Wang, Li-Juan | Jia, Xin | Feng, Si-Hui | Xia, Shu-Mei | Wu, Yi-Ning | Qi, Hong
To estimate the pollution of As and Pb in the Songhua River which flows through the major rice-producing regions in China, the present study investigated the level and release of As and Pb in surficial sediments which collected from nine sites in Songhua River (M₁–M₉). The concentration of As and Pb was ranged as follows: As = 3.104~15.01 μg/g, Pb = 20.10~37.42 μg/g; the average concentration: As = 6.466 ± 3.077 μg/g, Pb = 28.88 ± 5.077 μg/g. By analysis vertically, the average concentration of As was 5.166 ± 1.496 μg/g in the upstream, 5.815 ± 1.793 μg/g in the midstream, and 9.716 ± 4.977 μg/g in the downstream. The average concentration of Pb was 27.83 ± 4.552 μg/g in the upstream, 28.66 ± 6.333 μg/g in the midstream, and 30.99 ± 4.837 μg/g in the downstream. It indicated that the concentration of As and Pb increased gradually from upstream to downstream. As existed mainly as insoluble state and Pb existed mainly as sulfide and organic combining state in surficial sediments, and the species of As and Pb could transform with the change of the circumstance. The release of quantity of As was higher than Pb. The pH of 6 was not conducive to the release of As and Pb. When the temperature was 35 and 6 °C, the release of As and Pb in surficial sediments were restrained, respectively. Fumaric acid and citric acid played an important role in promoting the release of As, but not conducive to Pb. Furthermore, the reasonable aeration rate was beneficial to the release process of As and Pb in surficial sediment. By kinetic analysis, the Elovich equation (Ct = 84.931–8.952lnt) could be used to describe the dynamic process of the release of As in a relatively short time. The Elovich equation (C ₜ = 2.724 + 1.3724lnt) and double constant rate equation (lnC T = 1.4646 + 0.1522lnT) could well describe the dynamics process of the release of Pb.
Afficher plus [+] Moins [-]A mini review of fluoride-induced apoptotic pathways Texte intégral
2018
Wei, Qin | Deng, Huidan | Cui, Hengmin | Fang, Jing | Zuo, Zhicai | Deng, Junliang | Li, Yinglun | Wang, Xun | Zhao, Ling
Fluorine or fluoride can have toxic effects on bone tissue and soft tissue at high concentrations. These negative effects include but not limited to cytotoxicity, immunotoxicity, blood toxicity, and oxidative damage. Apoptosis plays an important role in fluoride-induced toxicity of kidney, liver, spleen, thymus, bursa of Fabricius, cecal tonsil, and cultured cells. Here, apoptosis activated by high level of fluoride has been systematically reviewed, focusing on three pathways: mitochondrion-mediated, endoplasmic reticulum (ER) stress-mediated, and death receptor-mediated pathways. However, very limited reports are focused on the death receptor-mediated apoptosis pathways in the fluoride-induced apoptosis. Therefore, understanding and discovery of more pathways and molecular mechanisms of fluoride-induced apoptosis may contribute to designing measures for preventing fluoride toxicity.
Afficher plus [+] Moins [-]Quantitative analysis of the coupling coefficients between energy flow, value flow, and material flow in a Chinese lead-acid battery system Texte intégral
2018
Yu, Yanxu | Song, Yao | Mao, Jiansu
To reveal the historic characteristics of the material flow, energy flow and value flow in a lead-acid battery (LAB) system, a framework for the coupling relationship among the three flows was established based on material flow analysis and the characteristics of the energy and value flows. The coupling coefficients between energy and material (CCEM) and value and material (CCVM) were also defined. The investigation used by China as a case to study changes in stages and the historic evolution. The results show that the CCEM for lead in LABs was highest in the usage stage, approximately 5–16 times greater than in the other stages. The CCEM for production was almost twice as high for primary lead as for secondary lead, and the CCEM was lowest for the fabrication and product manufacture stage. The CCVM for lead in LABs was 2.5–6 times higher than for other types of lead. The CCVM was lower for scrap lead than for lead ore, and the CCVM was approximately 1.7 times higher for refined lead than for scrap and refined lead. For lead trade, CCVM was correlated with domestic and overseas markets. From 1990 to 2014, the CCEM for each stage was in decline, whereas the opposite was the case for CCVM. The influencing factors were analyzed in terms of resources, the environment, and markets. Increasing the circulation rate of scrap lead is an effective way to rapidly save resources, reduce lead pollution, and promote a circular economy. The limitations and potential value of the study are also highlighted, and future research is outlined.
Afficher plus [+] Moins [-]Comparative study of selenium and selenium nanoparticles with reference to acute toxicity, biochemical attributes, and histopathological response in fish Texte intégral
2018
Kumar, Neeraj | Krishnani, KishoreKumar | Singh, NarendraPratap
Recent studies have demonstrated that selenium (Se) and selenium nanoparticles (Se-NPs) exhibited toxicity at a higher concentration. The lethal concentration of Se and Se-NPs was estimated as 5.29 and 3.97 mg/L at 96 h in Pangasius hypophthalmus. However, the effect of different definite concentration of Se (4.5, 5.0, 5.5, and 6.0 mg/L) and Se-NPs (2.5, 3.0, 3.5, and 4.0 mg/L) was decided for acute experiment. Selenium and Se-NPs alter the biochemical attributes such as anti-oxidative status [catalase (CAT), superoxide dismutase (SOD), and glutathione-S-transferase (GST) activities], neurotransmitter enzyme, cellular metabolic enzymes, stress marker, and histopathology of P. hypophthalmus in a dose- and time-dependent manner. CAT, SOD, and GST were significantly elevated (p < 0.01) when exposed to Se and Se-NPs, and similarly, a neurotransmitter enzyme (acetylcholine esterase (AChE)) was significantly inhibited in a time- and dose-dependent manner. Further, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and malate hydrogenase were noticeably (p < 0.01) affected by Se and Se-NPs from higher concentration to lower concentration. Stress markers such as cortisol and HSP 70 were drastically enhanced by exposure to Se and Se-NPs. All the cellular metabolic and stress marker parameters were elevated which might be due to hyperaccumulation of Se and Se-NPs in the vital organ and target tissues. The histopathology of liver and gill was also altered such as large vacuole, cloudy swelling, focal necrosis, interstitial edema, necrosis in liver, and thickening of primary lamellae epithelium and curling of secondary lamellae due to Se and Se-NP exposure. The study suggested that essential trace element in both forms (inorganic and nano) at higher concentration in acute exposure of Se and Se-NPs led to pronounced deleterious alteration on histopathology and cellular and metabolic activities of P. hypophthalmus.
Afficher plus [+] Moins [-]Nematicidal potential of Taraxacum officinale [Erratum: v. 25, no. 30 2018, p. 30066] Texte intégral
2018
Laquale, Sebastiano | Avato, Pinarosa | Argentieri, Maria Pia | Candido, Vincenzo | Perniola, Michele | D’Addabbo, Trifone
This study was aimed to investigate the activity of the Asteraceae species Taraxacum officinale against the root-knot nematode Meloidogyne incognita. Leaf and root extracts of T. officinale were tested in vitro at a range of 62.5–1000 and 250–1000 μg mL⁻¹ concentrations on nematode juveniles and eggs, respectively, whereas treatments with 10–40 g kg⁻¹ soil rates of dry leaf and root T. officinale biomass were applied to soil infested by M. incognita in greenhouse experiments on potted tomato. Peak 36 and 50% juvenile mortality and 14.8 and 23.8% egg hatchability reduction were recorded at the maximum concentration of leaf and root extracts, respectively. Soil treatments with T. officinale leaf and root material strongly suppressed nematode multiplication and gall formation on tomato roots and significantly increased plant growth. Chicoric acid and 3-O- and 3,5-di-O-caffeoylquinic acid were found to be the main components of leaf and root extract, respectively, and proved, as the total hydroalcoholic extracts from T. officinale leaf and root material, for an antioxidant activity. Data from this study indicate the suitability of plant materials from T. officinale for a potential formulation of nematicidal products to include in sustainable nematode management strategies.
Afficher plus [+] Moins [-]Variation of preserving organic matter bound in interlayer of montmorillonite induced by microbial metabolic process Texte intégral
2018
Zhao, Yulian | Dong, Faqin | Dai, Qunwei | Li, Gang | Ma, Jie
This paper aimed to investigate the variation of preserving organic matter bound in the interlayer space of montmorillonite (Mt) induced by a microbe metabolic process. We selected Bacillus pumilus as the common soil native bacteria. The alteration of d ₀₀₁ value, functional group, and C,N organic matter contents caused by bacteria were analyzed by XRD, FTIR, and elementary analyzer, respectively. XRD results showed that the d ₀₀₁ value of montmorillonite increased with the concentration decreasing and decreased with the culture time increasing after interacting with bacteria indicating the interlayer space of montmorillonite was connected with the organic matter. The findings of long-term interaction by resetting culture conditions implied that the montmorillonite buffered the organic matter when the nutrition was enough and released again when the nutrition was lacking. The results of the elementary analyzer declared the content of organic matter was according to the d ₀₀₁ value of montmorillonite and N organic matter which played a major impact. FTIR results confirmed that the Si-O stretching vibrations of Mt were affected by the functional group of organic matter. Our results showed that the montmorillonite under the influence of soil bacteria has a strong buffering capacity for preserving organic matter into the interlayer space in a short-term. It might provide critical implications for understanding the evolution process and the preservation of fertilization which was in the over-fertilization or less-fertilization conditions on farmland.
Afficher plus [+] Moins [-]Use of a combination of in vitro models to investigate the impact of chlorpyrifos and inulin on the intestinal microbiota and the permeability of the intestinal mucosa Texte intégral
2018
Réquilé, Marina | Gonzàlez Alvarez, Dubàn O. | Delanaud, Stéphane | Rhazi, Larbi | Bach, Véronique | Depeint, Flore | Khorsi-Cauet, Hafida
Dietary exposure to the organophosphorothionate pesticide chlorpyrifos (CPF) has been linked to dysbiosis of the gut microbiota. We therefore sought to investigate whether (i) CPF’s impact extends to the intestinal barrier and (ii) the prebiotic inulin could prevent such an effect. In vitro models mimicking the intestinal environment (the SHIME®) and the intestinal mucosa (Caco-2/TC7 cells) were exposed to CPF. After the SHIME® had been exposed to CPF and/or inulin, we assessed the system’s bacterial and metabolic profiles. Extracts from the SHIME®’s colon reactors were then transferred to Caco-2/TC7 cultures, and epithelial barrier integrity and function were assessed. We found that inulin co-treatment partially reversed CPF-induced dysbiosis and increased short-chain fatty acid production in the SHIME®. Furthermore, co-treatment impacted tight junction gene expression and inhibited pro-inflammatory signaling in the Caco-2/TC7 intestinal cell line. Whereas, an isolated in vitro assessment of CPF and inulin effects provides useful information on the mechanism of dysbiosis, combining two in vitro models increases the in vivo relevance.
Afficher plus [+] Moins [-]Antioxidative response in leaves and allelochemical changes in root exudates of Ricinus communis under Cu, Zn, and Cd stress Texte intégral
2018
Wang, Shuifeng | Zhao, Ye | Guo, Jinghua | Liu, Yuan
We have previously reported that Ricinus communis is a good candidate for the phytoremediation of Cd- and Zn-contaminated soil and for fuel production. In this study, changes in the activity of antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; and guaiacol peroxidase, POD) and the contents of chlorophyll and malondialdehyde (MDA) in R. communis leaves under Cu, Zn, and Cd stress were examined. Compounds from the exudate of R. communis roots were collected and analyzed using GC-MS chromatograms. The results of enzyme activity showed that Cd treatment significantly increased the SOD content of R. communis leaves and slightly elevated the CAT content, whereas the POD content increased markedly at low Cd treatment concentrations and decreased as Cd concentrations increased. Zn treatment distinctly elevated SOD and POD content in R. communis leaves but had no great influence on CAT content. Cu treatment slightly increased CAT activity, while Cu did not evidently change SOD and POD activity. We found 17, 29, 18, 18, and 33 different compounds in the R. communis root exudates from the control group and Cd, Cu, Zn, and Cd+Cu+Zn treatment groups, respectively. The root exudates mainly included ester, alcohol, ether, amide, acid, phenol, alkanes, ketone, aromatic hydrocarbon, and nitrile compounds. However, the root exudates of R. communis grown in uncontaminated soils were dominated by esters, alcohols, and ethers. Single Cu or Zn treatment slightly changed the root exudates, which were dominated by esters, alcohols, and amides. In the Cd and Cd+Cu+Zn treatment groups, the compositions of root exudates apparently increased, with alkanes as the major species (> 88%).
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