NANCI DO NASCIMENTO
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Resumo IPEN-doc 04676 Structural and biological alterations of crotoxin following irradiation in the presence of thiol groups1997 - NASCIMENTO, N.; ANDRIANI, E.P.; SPENCER, P.J.; ROGERO, J.R.Resumo IPEN-doc 04362 Effects of sup(60)Co gamma radiation on the antigenic and immunogenic properties of bothrops jararacussu venom1996 - SPENCER, P.J.; NASCIMENTO, N.; ROGERO, J.R.Resumo IPEN-doc 04682 Efeitos da radiacao gama de sup(60)Co nas propriedades antigenicas e imunogenicas do veneno de (bothrops jararacussu)1996 - SPENCER, P.J.; NASCIMENTO, N.; ROGERO, J.R.Resumo IPEN-doc 04685 Biochemical and immunological characterization of the main products of crotoxin irradiation1996 - NASCIMENTO, N.; CLISSA, P.B.; SPENCER, P.J.; ANDRADE JUNIOR, H.F.; KAISER, I.I.; ROGERO, J.R.Resumo 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 07248 Effects of sup(60)Co radiation on bothropstoxin-1 structure2000 - SPENCER, P.J.; BYME, M.; NASCIMENTO, N.; ROGERO, J.R.; SMITH, L.A.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 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 09898 Effects of gamma rays on the immunogenicity (IgG types) of ovalbumin2003 - BAPTISTA, J.A.; SPENCER, P.J.; AROEIRA, L.G.S.; CASARE, M.S.; NASCIMENTO, N.Ionizing radiation has been successfully employed to modify the immunological properties of biomolecules. Very promising results were obtained when crude animal venoms, as well as isolated toxins, were treated with gamma rays, yielding toxoids with good immunogenicity. However, little is known about the modifications that irradiated molecules undergo and even less about the immunological response that such antigens elicit. In the present work, we used ovalbumin as a model to investigate possible immunogenic differences between native and irradiated proteins. Native ovalbumin (2mg/ml in 150mM NaCl) was irradiated with 2kGy of 60Co gamma rays with a 570Gy/h dose rate. B10.PL mice (n=5) were then immunized with either the native or the irradiated protein. After three immunizations, serum samples were collected and the antibody titers and isotypes were determined by enzyme-linked immunoadsorbant assay. Our data indicate that no difference could be noticed when the antibody titers of the two groups were compared. However, the isotyping assays indicates that the native protein induced high levels of IgG1, while its irradiated counterpart displayed mostly IgG2b antibodies. These data suggest that after irradiation, an antigen known to induce a Th2 response, is able to switch the immune system towards a Th1 pattern.Artigo IPEN-doc 09895 Effects of sup(60)Co radiation on the molecular structure of crotamine2003 - CASARE, M.S.; BAPTISTA, J.A.; SPENCER, P.J.; NASCIMENTO, N.