Department of Chemistry, University of Londrina, Londrina, Paraná, Brazil. Research Laboratory of Applied Immunology, University of Londrina, Paraná, Brazil. Department of Rheumatology, Pontifícia Universidade Católica, PUC, Londrina, Paraná, Brazil. Department of Pathology, Clinical Analysis and Toxicology, University of Londrina, Rua Robert Koch, n 60, Londrina, Paraná, Brazil. Department of Internal Medicine, University of Londrina, Londrina, Paraná, Brazil. Department of Rheumatology, Pontifícia Universidade Católica, PUC, Londrina, Paraná, Brazil. deianame@yahoo.com.br. Department of Pathology, Clinical Analysis and Toxicology, University of Londrina, Rua Robert Koch, n 60, Londrina, Paraná, Brazil. deianame@yahoo.com.br.