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Letts R.E.,Grande Rio University | Letts R.E.,Cayetano Heredia Peruvian University | Pereira T.C.B.,Grande Rio University | Bogo M.R.,Grande Rio University | And 3 more authors.
Archives of Environmental Contamination and Toxicology | Year: 2011

Bacteria communities living in mucus secretions of common carp Cyprinus carpio (Cyprinidae) were exposed to the organic nanomaterial fullerene (C 60) to evaluate its potential bactericidal effects. End points analyzed were viability, growth, reactive oxygen species (ROS) concentration, and total antioxidant competence against peroxyl radicals. Viability was not affected (p > 0.05), whereas growth was arrested (p < 0.05) after 3 hours of exposure to the three concentration of C 60 assayed (0.1, 1, and 10 mg/L). Levels of RO measured at different C 60 concentration showed that some colonies were reactive (significant dose-response relation, p < 0.05) to C 60, whereas others were not. The nonreactive colonies to C 60 presented higher antioxidant competence to peroxyl radicals compared with the reactive colonies (p < 0.05). The strains isolated and identified by polymerase chain reaction (PCR) products of 16S rRNA showed a predominance of Aeromonas genus between all the isolated Gram-negative bacteria. Thus, the present results indicate that C 60 affects bacterial communities that live in mucus secretions of common carp. © 2010 Springer Science+Business Media, LLC.

Dal Forno G.O.,Grande Rio University | Kist L.W.,Grande Rio University | Kist L.W.,Instituto Nacional Of Ciencia E Tecnologia Translacional Em Medicina Inct Tm | De Azevedo M.B.,Grande Rio University | And 11 more authors.
BioMed Research International | Year: 2013

Even though technologies involving nano/microparticles have great potential, it is crucial to determine possible toxicity of these technological products before extensive use. Fullerenes C60 are nanomaterials with unique physicochemical and biological properties that are important for the development of many technological applications. The aim of this study was to evaluate the consequences of nonphotoexcited fullerene C60 exposure in brain acetylcholinesterase expression and activity, antioxidant responses, and oxidative damage using adult zebrafish as an animal model. None of the doses tested (7.5, 15, and 30 mg/kg) altered AChE activity, antioxidant responses, and oxidative damage when zebrafish were exposed to nonphotoexcited C 60 nano/microparticles during 6 and 12 hours. However, adult zebrafish exposed to the 30 mg/kg dose for 24 hours have shown enhanced AChE activity and augmented lipid peroxidation (TBARS assays) in brain. In addition, the up-regulation of brain AChE activity was neither related to the transcriptional control (RT-qPCR analysis) nor to the direct action of nonphotoexcited C60 nano/microparticles on the protein (in vitro results) but probably involved a posttranscriptional or posttranslational modulation of this enzymatic activity. Taken together these findings provided further evidence of toxic effects on brain after C60 exposure. © 2013 Gonzalo Ogliari Dal Forno et al.

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