NANCI DO NASCIMENTO
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Resumo IPEN-doc 22219 Estudo de toxinas irradiadas com radiação gama de sup(60)Co - comportamento do sistema imune2005 - CAPRONI, PRISCILA; NASCIMENTO, NANCI doResumo IPEN-doc 05336 Influência das espécies reativas formadas a partir da irradiação de proteínas2004 - BACETI, ANDRE A.; NASCIMENTO, NANCI doResumo IPEN-doc 22078 Clonagem e expressão de toxina de interesse farmacológico2006 - LEINMUELLER, MILENA de M.C.; NASCIMENTO, NANCI doResumo IPEN-doc 12611 Bioconjugado de policaprolactona (PCL) com crotoxina2006 - LORENZETTI, S.G.; HIGA, O.Z.; CAMILLO, M.A.P.; NASCIMENTO, N.; QUEIROZ, A.A.A.Resumo IPEN-doc 14132 Molecular modification of irradiated serpent venom FTIR2009 - OLIVEIRA, KARINA C. de; ALBERO, FELIPE G.; ZEZELL, DENISE M.; NASCIMENTO, NANCI doResumo IPEN-doc 13668 Immunological properties of sup(60)Co gamma rays irradiated bothropstoxin-I2008 - BAPTISTA, J.A.; VIEIRA, D.P.; GALISTEO JUNIOR, A.J.; CAPRONI, P.; CASARE, M.; ANDRADE JUNIOR, H.F.; SPENCER, P.J.; NASCIMENTO, N.Artigo IPEN-doc 10737 Immune response against bothropstoxin-I irradiated with sup(60) gamma rays2005 - BAPTISTA, J.A.; SPENCER, P.J.; HIGA, O.Z.; ANDRADE JUNIOR, H.F.; CESARE, M.S.; CAMPOS, L.A.; NASCIMENTO, N.Artigo IPEN-doc 15163 Evaluation of moniotoxic activity of bothropstoxin-1 irradiated with sup(60)Co gamma rays2009 - MIRCO, JESSICA; BAPTISTA, JANAINA A.; CAPRONI, PRISCILA; YOSHITO, DANIELE; NASCIMENTO, NANCIIonizing radiation has been successfully employed to modify the immunological properties of biomolecules and has been proven to be a powerful tool to attenuate snake venoms toxicity without affecting their immunogenic properties. Snake venoms and their isolated toxins showed structural modifications after gamma radiation process, in aqueous solution, mainly by water radiolysis sub products. Free radical scavengers, such as NaNO3 and t-butanol, present selective effects on specific radical from water radiolysis. The NaNO3 has affinity by aqueous electron, while the t-butanol has affinity by hydroxyl radical. At the present work, we have investigated the miotoxic activity of bothropstoxin-1 (BTHX-1), a K49 phospholipase, present in Bothrops jararacussu crude venom, before and after irradiation process, with or without scavenger substances presence. BTHX-1 was irradiated with 2kGy of 60Co gamma rays, in aqueous solution and in the presence of oxygen. BALB/c mice were inoculated with either native or irradiated toxin, with or without scavenger substances. After 3 hours, blood samples were collected and the miotoxic activity was evaluated by LDH (lactate dehydrogenase) release. The muscular tissue damage was directly related to the LDH amounts released. Irradiated bothropstoxin-1, with or without NaNO3 substance, caused less damage than their native counterpart. But irradiated toxin, in the presence of t-butanol, was so miotoxic as the native BTHX-1. These results indicate that irradiation of toxic proteins can promote significant modifications on their structures, but still retaining many of the original biological properties of their native counterparts. Additionally, some scavengers substances can change these gamma radiation effects.Artigo IPEN-doc 15156 Physico-chemical characterization of gamma rays irradiated crotamine2009 - OLIVEIRA, KARINA C. de; SPENCER, PATRICK J.; NASCIMENTO, NANCIIonizing radiation can change the molecular structure and affect the biological properties of biomolecules. It has been employed to attenuate animal toxins. Crotamine, a toxin from Crotalus durissus terrificus (Cdt), is a highly basic polypeptide (pI - 10.3), with myotoxic activity and molecular weight of 4882 Da. It is composed of 42 amino acids residues and reticulated by three disulfide bonds. This study aimed the characterization of irradiated crotamine using Circular Dichroism (CD), Fluorescence Spectroscopy and Differential Scanning Calorimetry (DSC) techniques. We used size exclusion and ion-exchange chromatography to purify it from Cdt crude venom. The pure crotamine was irradiated with 2.0 kGy from a 60Co source. Native and irradiated crotamine were analyzed in a fluorescence spectrophotometer (Hitachi F-4500), under excitation wavelength at 275 nm and the emission was scanned from 300 to 500 nm. The analysis of fluorescence quenching showed that the irradiated form displayed a lower quantum yield when compared to the native form. CD spectra, obtained from a Jasco, J-180 spectropolarimeter, of native and irradiated crotamine solutions, showed a discrete change between the samples, from apparently ordered conformation to a random coil. Finally, the thermodynamics analysis, realized in a calorimeter METTLER TOLEDO, DSC 822e, showed that irradiation promoted changes in the calorimetric profile. Our results indicate that irradiation leads to progressive changes in the structure of the toxin, which could explain the decrease in myotoxic activity.Artigo IPEN-doc 12627 Estudo das propriedades biocompativeis do bioconjulgado de poli(epsilon caprolactona)-crotoxina2006 - LORENZETTI, S.G.; HIGA, O.Z.; CAMILLO, M.A.P.; NASCIMENTO, N.; QUEIROZ, A.A.A.