ADRIANA KUCHINSKI CAVALCANTE
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Resumo IPEN-doc 25384 Radiolytic synthesis of non-toxic, size-homogeneous gold nanoparticles2018 - FREITAS, L.F. de; CAVALCANTE, A.K.; LUGAO, A.B.Radiolytic synthesis of nanoparticles is one of the successful examples of Green Chemistry (the use of non-toxic chemicals, environmentally benign solvents and renewable materials during the chemical processes), in which the reducing agents responsible for the particle nucleation are no other than the reactive species generated by the radiolysis of the solvent itself (i.e. water, acetone or alcohols). This study consists on the radiolytic synthesis and characterization of gold nanoparticles, as well as the assessment of their toxicity levels to Zebrafish embryos (Danio rerio), as an indication of a possible environmental effect. The nanoparticles were synthesized by mixing: NaAuCl4 2 x 10-3 M; polyvinylpyrrolidone 100 kDa 0.5% (as size stabilizer); propan-2-ol 0.2 M and acetone 0.06 M (for the generation of propyl radicals); and AgNO3 6 x 10-5 M (another size stabilizer), followed by 10 kGy of gamma radiation (5 kGy h-1) [1]. The particles were characterized by their absorption spectra in the UV and visible, and the dynamic light scattering (DLS) technique was used to assess their hydrodynamic size. Finally, the impact on the development of Zebrafish embryos was investigated for different dilutions of the nanoparticles suspension, according to the OECD protocol nº 236 (Guideline on Fish Embryo Acute Toxicity Test – FET), as a means of assessing the environmental impact of the nanomaterial. An acute (96 hours of exposition to gold nanoparticles) and a chronic (168 hours of exposition) assay were performed. The particles were successfully synthesized in a multipurpose gamma irradiator, with an absorption peak at 532 nm and a narrow size distribution (around 80 nm). There was no evident toxicity for the fish in any tested concentration, leading to the conclusion that this green method of nanoparticle synthesis generates a potentially environment-safe material, with good control of size and optical properties.Artigo IPEN-doc 24466 Evaluation of resveratrol toxicity in the embryolarval stage of Danio rerio fish2017 - CAVALCANTE, A.K.; LOPES-FERREIRA, M.; ROGERO, S.O.; ROGERO, J.R.Human beings concern about healthy life has driven researchers to study new compounds capable of reaching that desire. Resveratrol (3, 4 ‘, 5-trihydroxystilbene) a phenolic compound, is one of these substances which presents a variety of pharmacological actions, as antioxidant potential, anti-inflammatory capacity, protection against heart and cancer diseases. Despite the resveratrol health benefits studies, there is a little evidence of its toxicity in the literature in aquatic organisms, and especially the data on the concentration of resveratrol in the environment, making the present study fundamental for information about resveratrol ecotoxicity in the aquatic system. The aim of this study was to evaluate the toxicity of resveratrol in embryos and larvae of Danio rerio (zebrafish). The in vitro cytotoxicity and ecotoxicity assays were performed. The IC50 obtained in the NCTC-L929 cell line cytotoxicity assay was 38.5 mg L-1. The LC50 (96h) obtained in fish embryo toxicity test was 75.3 mg L-1 and the mean value of resveratrol LC50 (168h) obtained in the short-term chronic ecotoxicity assays performed with zebrafish larvae was 51.4 mg L-1. This work provided data on the toxicity of resveratrol in the embryonic stage of fish of the species Danio rerio and the toxic effects are dependent on its concentration.Artigo IPEN-doc 24145 Resveratrol radiomodifier effect on Danio rerio embriolarval assay2017 - DAMASCENO, KELME C.; MAMEDE, FERNANDA C.S.; CAVALCANTE, ADRIANA K.; ROGERO, SIZUE O.; FERREIRA, MONICA L.; ROGERO, JOSE R.The ionizing radiation can cause fatal damages to cells by the direct interaction with DNA and RNA or a series of toxic reactions occasioning chemical and biological changes. There are compounds with radioprotective potential, like resveratrol. For use the organism. Resveratrol is a substance found in peanuts, grapes and wine and its production occurs in plants as a response to physical, chemical and biological stress. Some studies benefits. Danio rerio (zebrafish) is a vertebrate animal and has become the model of several studies related to human diseases, due to its genomes similarity of 70 %, rapid embryonic development and the transparency o the eggs, which make it possible to observe the effects during the test period. The aim of the present study to verify the resveratrol radiomodifier effect on zebrafish during the embryolarval development by modified Fish Embryo Acute Toxicity (FET) (LC50) was 66.9 mg.L-1. Before, to understand the effects of radiation, was carried out the gamma radiation lethal dose (LD50) assay and the LD50 was 25 Gy. With these results the projec study of the radiomodifier effect of resveratrol in the presence of gamma radiation