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[PMID]:29378162
[Au] Autor:Vila L; García-Rodríguez A; Cortés C; Velázquez A; Xamena N; Sampayo-Reyes A; Marcos R; Hernández A
[Ad] Endereço:Grup de Mutagènesi, Departament de Genètica i de Microbiologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, Spain.
[Ti] Título:Effects of cerium oxide nanoparticles on differentiated/undifferentiated human intestinal Caco-2 cells.
[So] Source:Chem Biol Interact;283:38-46, 2018 Mar 01.
[Is] ISSN:1872-7786
[Cp] País de publicação:Ireland
[La] Idioma:eng
[Ab] Resumo:Since ingestion constitute one of the main routes of nanoparticles (NPs) exposure, intestinal cells seems to be a suitable choice to evaluate their potential harmful effects. Caco-2 cells, derived from a human colon adenocarcinoma, have the ability to differentiate forming consistent cell monolayer structures. For these reasons Caco-2 cells, both in their undifferentiated or differentiated state, are extendedly used. We have used well-structured monolayers of differentiated Caco-2 cells, as a model of intestinal barrier, to evaluate potential harmful effects associated to CeO NPs exposure via ingestion. Different parameters such as cell toxicity, monolayer integrity and permeability, cell internalization, translocation through the monolayer, and induction of DNA damage were evaluated. No toxic effects of CeO NPs were observed, independently of the differentiated state of the Caco-2 cells. In the same way, no effects on the monolayer integrity/permeability were observed. Although important cell uptake was demonstrated in undifferentiated cells (by using confocal microscopy), CeO NPs remained mostly attached to the apical membrane in the differentiated cells. In spite of this apparent lack of uptake in differentiated cells, translocation of CeO NPs to the basolateral chamber was observed by using confocal microscopy. Finally no genotoxic effects were observed when the comet assay was used, although decreases in the levels of oxidized bases were observed, supporting the antioxidant role of CeO NPs.
[Mh] Termos MeSH primário: Diferenciação Celular/efeitos dos fármacos
Cério/química
Nanopartículas Metálicas/toxicidade
[Mh] Termos MeSH secundário: Células CACO-2
Membrana Celular/efeitos dos fármacos
Membrana Celular/metabolismo
Permeabilidade da Membrana Celular/efeitos dos fármacos
Sobrevivência Celular/efeitos dos fármacos
Dano ao DNA/efeitos dos fármacos
Seres Humanos
Intestinos/citologia
Intestinos/metabolismo
Nanopartículas Metálicas/química
Microscopia Confocal
Tamanho da Partícula
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
30K4522N6T (Cerium); 619G5K328Y (ceric oxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180130
[St] Status:MEDLINE


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[PMID]:29232572
[Au] Autor:Pandiyan N; Murugesan B; Sonamuthu J; Samayanan S; Mahalingam S
[Ad] Endereço:Advanced Green Chemistry Lab, Department of Industrial Chemistry, School of Chemical Sciences, Alagappa University, Karaikudi 630 003, Tamil Nadu, India.
[Ti] Título:Facile biological synthetic strategy to morphologically aligned CeO /ZrO core nanoparticles using Justicia adhatoda extract and ionic liquid: Enhancement of its bio-medical properties.
[So] Source:J Photochem Photobiol B;178:481-488, 2018 Jan.
[Is] ISSN:1873-2682
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:In this study, a typical green synthesis route has approached for CeO /ZrO core metal oxide nanoparticles using ionic liquid mediated Justicia adhatoda extract. This synthesis method is carried out at simple room temperature condition to obtain the core metal oxide nanoparticles. XRD, SEM and TEM studies employed to study the crystalline and surface morphological properties under nucleation, growth, and aggregation processes. CeO /ZrO core metal oxides display agglomerated nano stick-like structure with 20-45nm size. GC-MS spectroscopy confirms the presence of vasicinone and N,N-Dimethylglycine present in the plant extract, which are capable of converting the corresponding metal ion precursor to CeO /ZrO core metal oxide nanoparticles. In FTIR, the corresponding stretching for Ce-O and Zr-O bands indicated at 498 and 416cm and Raman spectroscopy also supports typical stretching frequencies at 463 and 160cm . Band gap energy of the CeO /ZrO core metal oxide is 3.37eV calculated from UV- DRS spectroscopy. The anti-bacterial studies performed against a set of bacterial strains the result showed that core metal oxide nanoparticles more susceptible to gram-positive (G+) bacteria than gram-negative (G-) bacteria. A unique feature of the antioxidant behaviors core metal oxides reduces the concentration of DPPH radical up to 89%. The CeO /ZrO core metal oxide nanoparticles control the S. marcescent bio-film formation and restrict the quorum sensing. The toxicology behavior of CeO /ZrO core metal oxide NPs is found due to the high oxygen site vacancies, ROS formation, smallest particle size and higher surface area. This type of green synthesis route may efficient and the core metal oxide nanoparticles will possess a good bio-medical agent in future.
[Mh] Termos MeSH primário: Antibacterianos/química
Cério/química
Líquidos Iônicos/química
Justicia/química
Nanopartículas Metálicas/química
Zircônio/química
[Mh] Termos MeSH secundário: Antibacterianos/farmacologia
Antioxidantes/química
Biofilmes/efeitos dos fármacos
Bactérias Gram-Negativas/efeitos dos fármacos
Bactérias Gram-Positivas/efeitos dos fármacos
Química Verde
Justicia/metabolismo
Nanopartículas Metálicas/toxicidade
Microscopia Eletrônica de Varredura
Tamanho da Partícula
Extratos Vegetais/química
Folhas de Planta/química
Folhas de Planta/metabolismo
Percepção de Quorum/efeitos dos fármacos
Serratia marcescens/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Antioxidants); 0 (Ionic Liquids); 0 (Plant Extracts); 30K4522N6T (Cerium); 619G5K328Y (ceric oxide); C6V6S92N3C (Zirconium); S38N85C5G0 (zirconium oxide)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171213
[St] Status:MEDLINE


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[PMID]:29101857
[Au] Autor:Dumitrescu E; Karunaratne DP; Babu SV; Wallace KN; Andreescu S
[Ad] Endereço:Department of Chemistry and Biomolecular Science, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699, USA.
[Ti] Título:Interaction, transformation and toxicity assessment of particles and additives used in the semiconducting industry.
[So] Source:Chemosphere;192:178-185, 2018 Feb.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Chemical mechanical planarization (CMP) is a widely used technique for the manufacturing of integrated circuit chips in the semiconductor industry. The process generates large amounts of waste containing engineered particles, chemical additives, and chemo-mechanically removed compounds. The environmental and health effects associated with the release of CMP materials are largely unknown and have recently become of significant concern. Using a zebrafish embryo assay, we established toxicity profiles of individual CMP particle abrasives (SiO and CeO ), chemical additives (hydrogen peroxide, proline, glycine, nicotinic acid, and benzotriazole), as well as three model representative slurries and their resulting waste. These materials were characterized before and after use in a typical CMP process in order to assess changes that may affect their toxicological profile and alter their surface chemistry due to polishing. Toxicity outcome in zebrafish is discussed in relation with the physicochemical characteristics of the abrasive particles and with the type and concentration profile of the slurry components pre and post-polishing, as well as the interactions between particle abrasives and additives. This work provides toxicological information of realistic CMP slurries and their polishing waste, and can be used as a guideline to predict the impact of these materials in the environment.
[Mh] Termos MeSH primário: Cério/toxicidade
Embrião não Mamífero/efeitos dos fármacos
Resíduos Industriais/efeitos adversos
Semicondutores
Dióxido de Silício/toxicidade
Peixe-Zebra/embriologia
[Mh] Termos MeSH secundário: Animais
Cério/química
Exposição Ambiental/efeitos adversos
Peróxido de Hidrogênio/química
Peróxido de Hidrogênio/toxicidade
Dióxido de Silício/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Industrial Waste); 30K4522N6T (Cerium); 619G5K328Y (ceric oxide); 7631-86-9 (Silicon Dioxide); BBX060AN9V (Hydrogen Peroxide)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180130
[Lr] Data última revisão:
180130
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171105
[St] Status:MEDLINE


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[PMID]:28741972
[Au] Autor:Dekkers S; Miller MR; Schins RPF; Römer I; Russ M; Vandebriel RJ; Lynch I; Belinga-Desaunay MF; Valsami-Jones E; Connell SP; Smith IP; Duffin R; Boere JAF; Heusinkveld HJ; Albrecht C; de Jong WH; Cassee FR
[Ad] Endereço:a National Institute for Public Health and the Environment , Bilthoven , The Netherlands.
[Ti] Título:The effect of zirconium doping of cerium dioxide nanoparticles on pulmonary and cardiovascular toxicity and biodistribution in mice after inhalation.
[So] Source:Nanotoxicology;11(6):794-808, 2017 Aug.
[Is] ISSN:1743-5404
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Development and manufacture of nanomaterials is growing at an exponential rate, despite an incomplete understanding of how their physicochemical characteristics affect their potential toxicity. Redox activity has been suggested to be an important physicochemical property of nanomaterials to predict their biological activity. This study assessed the influence of redox activity by modification of cerium dioxide nanoparticles (CeO NPs) via zirconium (Zr) doping on the biodistribution, pulmonary and cardiovascular effects in mice following inhalation. Healthy mice (C57BL/6 J), mice prone to cardiovascular disease (ApoE , western-diet fed) and a mouse model of neurological disease (5 × FAD) were exposed via nose-only inhalation to CeO NPs with varying amounts of Zr-doping (0%, 27% or 78% Zr), or clean air, over a four-week period (4 mg/m for 3 h/day, 5 days/week). Effects were assessed four weeks post-exposure. In all three mouse models CeO NP exposure had no major toxicological effects apart from some modest inflammatory histopathology in the lung, which was not related to the amount of Zr-doping. In ApoE mice CeO did not change the size of atherosclerotic plaques, but there was a trend towards increased inflammatory cell content in relation to the Zr content of the CeO NPs. These findings show that subacute inhalation of CeO NPs causes minimal pulmonary and cardiovascular effect four weeks post-exposure and that Zr-doping of CeO NPs has limited effect on these responses. Further studies with nanomaterials with a higher inherent toxicity or a broader range of redox activities are needed to fully assess the influence of redox activity on the toxicity of nanomaterials.
[Mh] Termos MeSH primário: Sistema Cardiovascular/efeitos dos fármacos
Cério/toxicidade
Pulmão/efeitos dos fármacos
Nanopartículas/toxicidade
Zircônio/química
[Mh] Termos MeSH secundário: Animais
Sistema Cardiovascular/metabolismo
Sistema Cardiovascular/patologia
Cério/química
Cério/farmacocinética
Exposição por Inalação
Pulmão/metabolismo
Pulmão/patologia
Camundongos
Camundongos Endogâmicos C57BL
Camundongos Knockout para ApoE
Nanopartículas/química
Oxirredução
Placa Aterosclerótica/induzido quimicamente
Distribuição Tecidual
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
30K4522N6T (Cerium); 619G5K328Y (ceric oxide); C6V6S92N3C (Zirconium)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180104
[Lr] Data última revisão:
180104
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170726
[St] Status:MEDLINE
[do] DOI:10.1080/17435390.2017.1357214


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[PMID]:29031448
[Au] Autor:Xue S; He H; Fan Q; Yu C; Yang K; Huang W; Zhou Y; Xie Y
[Ad] Endereço:School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China.
[Ti] Título:La/Ce-codoped Bi O composite photocatalysts with high photocatalytic performance in removal of high concentration dye.
[So] Source:J Environ Sci (China);60:70-77, 2017 Oct.
[Is] ISSN:1001-0742
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:A series of La/Ce-codoped Bi O composite photocatalysts were fabricated via hydrothermal-calcination process. The as-prepared products were intensively characterized by some physicochemical characterizations like N physical adsorption, X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), UV-Vis diffuse reflectance (UV-Vis DRS), Fourier transform infrared spectroscopy (FT-IR), photoelectrochemical measurements, and photoluminescence (PL) spectroscopy. The characterization results indicated that La and Ce doping induced obvious crystal phase transformation in Bi O , from monoclinic to tetragonal phase. La and Ce codoping also gave rise to the obvious synergetic effects, e.g., the lattice contraction of Bi O , the decrease of crystal size and the increase of surface area. The photocatalytic performance of the prepared catalysts was evaluated by removal of dye acid orange II with high concentration under visible light irradiation. Results showed that La/Ce-codoped Bi O displayed much higher photocatalytic performance than that of bare Bi O , single La or Ce doped Bi O samples. The superior photocatalytic activity was mainly attributed to the improved texture and surface properties and the synergistic effects of La and Ce codoping on suppressing the recombination of photo-generated electrons (e ) and holes (h ).
[Mh] Termos MeSH primário: Bismuto/química
Corantes/química
Processos Fotoquímicos
[Mh] Termos MeSH secundário: Adsorção
Compostos Azo/química
Cério/química
Modelos Químicos
Naftalenos/química
Propriedades de Superfície
Eliminação de Resíduos Líquidos/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acid Orange II); 0 (Azo Compounds); 0 (Coloring Agents); 0 (Naphthalenes); 30K4522N6T (Cerium); A6I4E79QF1 (bismuth oxide); U015TT5I8H (Bismuth)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171017
[St] Status:MEDLINE


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[PMID]:28869625
[Au] Autor:Nakonieczny DS; Paszenda ZK; Basiaga M; Radko T; Drewniak S; Podwórny J; Bogacz W
[Ad] Endereço:Department of Biomaterials and Medical Devices Engineering, Faculty of Biomedical Engineering, Silesian University of Technology, Zabrze, Poland.
[Ti] Título:Phase composition and morphology characteristics of ceria-stabilized zirconia powders obtained via sol-gel method with various pH conditions.
[So] Source:Acta Bioeng Biomech;19(2):21-30, 2017.
[Is] ISSN:1509-409X
[Cp] País de publicação:Poland
[La] Idioma:eng
[Ab] Resumo:PURPOSE: High purity, fine crystalline, degradation-free at low temperature powders have attracted special interest in CAD/CAM prosthetic dentistry full ceramic restorations. This study reports the preparation and characterisation of zirconia-ceria (0.9 ZrO2 0.1 CeO2) powders. Materials were obtained from zirconium-n-alkoxide and cerium nitrate hexahydrate in the pH 2-4 and 8-10. METHODS: Zirconia- ceria powders were obtained with the sol-gel method in a humid-free environment. Thermal analysis (TGA/DTA) of the as-prepared materials was made for an assessment of its behaviour at elevated temperatures. Specimens were dried at 80 °C and calcinated in two stages: at 300 °C with soaking time 2.5 h and 850 °C with holding time 2.5 h, in order to evaluate the phase transformations. Thermal analyses of the as-dried powders were made for an assessment of its thermal behaviour during heat treatment up to 1000 °C. By X-ray diffraction (XRD), polymorphs of ZrO2 were identified. Additionally, scanning electron microscopy (SEM) and laser particle size distribution (PSD) were involved for characterisation of morphology of the powders. RESULTS: A correlation between the pH of the colloidal system and the morphology of the as-obtained powders were found. Based on analysis (SEM, PSD), structures were identified known as soft and hard agglomerates. CONCLUSIONS: It can be stated that differences found between powder morphology were dependent on the value pH used, which can be crucial for powder densification during sintering and compacting green bodies which, as a consequence, may be crucial for the lifetime of zirconia prostheses. Correlations between phase composition and pH are difficult to grasp, and require further, more sophisticated, studies.
[Mh] Termos MeSH primário: Cério/química
Coloides/química
Materiais Dentários/síntese química
Excipientes/química
Nanocompostos/química
Nanocompostos/ultraestrutura
Zircônio/química
[Mh] Termos MeSH secundário: Concentração de Íons de Hidrogênio
Teste de Materiais
Tamanho da Partícula
Transição de Fase
Pós
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Colloids); 0 (Dental Materials); 0 (Excipients); 0 (Powders); 30K4522N6T (Cerium); 619G5K328Y (ceric oxide); C6V6S92N3C (Zirconium); S38N85C5G0 (zirconium oxide)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170905
[St] Status:MEDLINE


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[PMID]:28735234
[Au] Autor:Feng Y; Lu H; Liu Y; Xue L; Dionysiou DD; Yang L; Xing B
[Ad] Endereço:Key Laboratory of Agro-Environment in Downstream of Yangtze Plain, Ministry of Agriculture, Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chin
[Ti] Título:Nano-cerium oxide functionalized biochar for phosphate retention: preparation, optimization and rice paddy application.
[So] Source:Chemosphere;185:816-825, 2017 Oct.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In this study, nano-cerium oxide functionalized maize straw biochar (Ce-MSB) was prepared and utilized to remove P from agricultural wastewater. Response Surface Model was applied to optimize the operating conditions. Moreover, Ce-MSB was applied to actual rice paddy column for the first time. Response Surface Model (RSM) showed higher materials ratio had positive effect on PO adsorption capacity, while higher pyrolysis temperature had negative effect. The maximum adsorption capacity of Ce-MSB for PO was 78 mg g , implying that Ce-MSB was an effective functionalized adsorbent for P removal. Paddy soil column experiment showed that application of Ce-MSB decreased total phosphorus concentration of surface water by 27.33% and increased total phosphors (TP) content of top soil by 7.22%. Further, Ce-MSB tends to increase rice plant height and leaf area. Therefore, Ce-MSB can be used as a promising functionalized biochar to reduce the risk of phosphorus loss from paddy field surface running water.
[Mh] Termos MeSH primário: Cério/química
Carvão Vegetal/química
Nanoestruturas/química
Fosfatos/química
Poluentes do Solo/química
[Mh] Termos MeSH secundário: Adsorção
Agricultura
Modelos Químicos
Oryza
Fósforo
Solo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Phosphates); 0 (Soil); 0 (Soil Pollutants); 0 (biochar); 16291-96-6 (Charcoal); 27YLU75U4W (Phosphorus); 30K4522N6T (Cerium); 619G5K328Y (ceric oxide)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170724
[St] Status:MEDLINE


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[PMID]:28728126
[Au] Autor:Wang L; Zhao Y; Zhang J
[Ad] Endereço:State Key Laboratory of Coal Combustion, Huazhong University of Science & Technology, Wuhan 430074, PR China.
[Ti] Título:Electrospun cerium-based TiO nanofibers for photocatalytic oxidation of elemental mercury in coal combustion flue gas.
[So] Source:Chemosphere;185:690-698, 2017 Oct.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Photocatalytic oxidation is an attractive method for Hg-rich flue gas treatment. In the present study, a novel cerium-based TiO nanofibers was prepared and selected as the catalyst to remove mercury in flue gas. Accordingly, physical/chemical properties of those nanofibers were clarified. The effects of some important parameters, such as calcination temperature, cerium dopant content and different illumination conditions on the removal of Hg using the photocatalysis process were investigated. In addition, the removal mechanism of Hg over cerium-based TiO nanofibers focused on UV irradiation was proposed. The results show that catalyst which was calcined at 400 °C exhibited better performance. The addition of 0.3 wt% Ce into TiO led to the highest removal efficiency at 91% under UV irradiation. As-prepared samples showed promising stability for long-term use in the test. However, the photoluminescence intensity of nanofibers incorporating ceria was significantly lower than TiO , which was attributed to better photoelectron-hole separation. Although UV and O are essential factors, the enhancement of Hg removal is more obviously related to the participation of catalyst. The coexistence of Ce and Ce , which leads to the efficient oxidation of Hg , was detected on samples. Hg is the final product in the reaction of Hg removal. As a consequence, the emissions of Hg from flue gas can be significantly suppressed. These indicate that combining photocatalysis technology with cerium-based TiO nanofibers is a promising strategy for reducing Hg efficiently.
[Mh] Termos MeSH primário: Poluentes Atmosféricos/química
Cério/química
Filtração/métodos
Mercúrio/química
Nanofibras/química
Titânio/química
[Mh] Termos MeSH secundário: Poluição do Ar/estatística & dados numéricos
Catálise
Carvão Mineral
Filtração/instrumentação
Luz
Oxirredução
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Air Pollutants); 0 (Coal); 15FIX9V2JP (titanium dioxide); 30K4522N6T (Cerium); D1JT611TNE (Titanium); FXS1BY2PGL (Mercury)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170721
[St] Status:MEDLINE


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[PMID]:28594294
[Au] Autor:Peng C; Chen Y; Pu Z; Zhao Q; Tong X; Chen Y; Jiang L
[Ad] Endereço:a Department of Environmental Science, College of Environmental Science and Engineering , Donghua University , Shanghai , China.
[Ti] Título:CeO nanoparticles alter the outcome of species interactions.
[So] Source:Nanotoxicology;11(5):625-636, 2017 Jun.
[Is] ISSN:1743-5404
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Despite considerable research on the environmental impacts of nanomaterials, we know little about how they influence interactions between species. Here, we investigated the acute (12 d) and chronic (64 d) toxicities of cerium oxide nanoparticles (CeO NPs) and bulk particles (0-200 mg/L) to three ciliated protist species (Loxocephalus sp., Paramecium aurelia, and Tetrahymena pyriformis) in single-, bi-, and multispecies microcosms. The results show that CeO NPs strongly affected the interactions between ciliated protozoan species. When exposed to the highest CeO NPs (200 mg/L), the intrinsic growth rates of Loxocephalus and Paramecium were significantly decreased by 18.87% and 88.27%, respectively, while their carrying capacities declined by more than 90%. However, CeO NP exposure made it difficult to predict outcomes of interspecific competition between species. At higher NP exposure (100 and 200 mg/L), competition led to the extinction of both species in the Loxocephalus and Paramecium microcosms that survived in the absence of competitors or CeO NPs. Further, the presence of potential competitors improved the survival of Loxocephalus to hundreds of individuals per milliliter in microcosms with Tetrahymena where Loxocephalus would otherwise not be able to tolerate high levels of NP exposure. This result could be attributed to weakened NP adsorption on the cell surface due to competitor-caused reduction of NP surface charge (from -18.52 to -25.17 mV) and intensified NP aggregation via phagocytosis of NPs by ciliate cells. Our results emphasize the need to explicitly consider species interactions for a more comprehensive understanding of the ecological consequences of NP exposure.
[Mh] Termos MeSH primário: Cério/toxicidade
Nanopartículas Metálicas/toxicidade
Paramecium aurelia
Tetrahymena pyriformis
[Mh] Termos MeSH secundário: Paramecium aurelia/efeitos dos fármacos
Paramecium aurelia/fisiologia
Especificidade da Espécie
Tetrahymena pyriformis/efeitos dos fármacos
Tetrahymena pyriformis/fisiologia
Testes de Toxicidade Aguda
Testes de Toxicidade Crônica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
30K4522N6T (Cerium); 619G5K328Y (ceric oxide)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170928
[Lr] Data última revisão:
170928
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170609
[St] Status:MEDLINE
[do] DOI:10.1080/17435390.2017.1340527


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[PMID]:28564630
[Au] Autor:Arasu MV; Thirumamagal R; Srinivasan MP; Al-Dhabi NA; Ayeshamariam A; Saravana Kumar D; Punithavelan N; Jayachandran M
[Ad] Endereço:Addiriyah Research Chair for Environmental Studies, Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia. Electronic address: mvalanarasu@gmail.com.
[Ti] Título:Green chemical approach towards the synthesis of CeO doped with seashell and its bacterial applications intermediated with fruit extracts.
[So] Source:J Photochem Photobiol B;173:50-60, 2017 Aug.
[Is] ISSN:1873-2682
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Nanomaterials of CeO with A. vera were synthesized by using simple chemical method. Grapes drops are used as an oxidizing agent. Structural and morphological studies of nanomaterials of cerium oxide (CeO ), were studied for combustion method of preparation. The precursor solution was initialized by a hydrothermal reaction. Cerium hydroxyl carbonate precursors which involves cerium (III) nitrate Ce(NO ) . 6 H O with (1.0M) of seashell powder, 3% A. vera, extracts, grapes and pomegranate drops and this complex solution was used to produce the CeO powder particles. We have prepared another sample with 5% of Aloe vera extract and found that 3% Aloe vera extract has lesser grain size and enhanced band gap values, so the article explained the sample analysis of combination with 3% extract of Aloe vera. The product has the rod pattern which was the unusual features appear to originate from the unique crystal chemistry aspects. From the optical absorption spectrum, it has been shown that the CeO rods have 3.847eV of direct band gap energy. The minimum inhibitory concentration (MIC) values of the synthesized compounds exhibited activity towards various microbial pathogens such as B. subtilis (15µg/mL), S. aureus (50µg/mL), S. epidermidis (20µg/mL), E. faecalis (25µg/mL) and towards E. coli (100µg/mL), K. pneumoniae (50µg/mL) and P. aeruginosa (75µg/mL) respectively. The tests on bacterial activities confirmed that the CeO rods are suitable hand for the biological applications. The seashell structure and the phytochemical contents of A. vera might enhance its bacterial activities.
[Mh] Termos MeSH primário: Exoesqueleto/química
Antibacterianos/química
Antibacterianos/síntese química
Cério/química
Nanopartículas Metálicas/química
[Mh] Termos MeSH secundário: Animais
Antibacterianos/farmacologia
Frutas/química
Frutas/metabolismo
Bactérias Gram-Negativas/efeitos dos fármacos
Bactérias Gram-Positivas/efeitos dos fármacos
Química Verde
Testes de Sensibilidade Microbiana
Extratos Vegetais/química
Espécies Reativas de Oxigênio/metabolismo
Espectroscopia de Infravermelho com Transformada de Fourier
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Plant Extracts); 0 (Reactive Oxygen Species); 30K4522N6T (Cerium); 619G5K328Y (ceric oxide)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171006
[Lr] Data última revisão:
171006
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170601
[St] Status:MEDLINE



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