Genetic characterization of orthobunyavirus Melao, strains BE AR633512 and BE AR8033, and experimental infection in golden hamsters (Mesocricetus auratus).

Melao virus (MELV) strains BE AR8033 and BE AR633512 were isolated from pools of Ochlerotatus scapularis mosquitoes in Belém, Pará State (1955), and Alta Floresta, Rondônia State (2000), Brazil, respectively. The aim of the present study was to molecularly characterize these strains and to describe the histopathological, biochemical and immunological changes in golden hamsters (Mesocricetus auratus) following intraperitoneal injection of MELV strains. Hamsters were susceptible to both of the MELV strains studied. Viraemia was observed 3-6 days post-infection (p.i.) for BE AR633512 and only on the second day p.i. for BE AR8033. Neutralizing antibodies against both strains were detected in blood samples obtained at 5 days p.i. and persisted up to 30 days p.i. Aspartate aminotransferase, alanine aminotransferase and blood urea nitrogen were significantly altered in animals infected with the two MELV strains, while creatinine was only altered in animals inoculated with BE AR633512. Histopathological changes were observed in the central nervous system, liver, kidney and spleen of hamsters, and infection was confirmed by detection of specific MELV antigens by immunohistochemistry. Strain BE AR633512 caused more severe tissue damage than strain BE AR8033, showing increased neurovirulence and pathogenicity. Genetic analysis based on the full-length sequences of the glycoprotein (Gn and Gc) and nucleocapsid protein (N) genes revealed high levels of homology between the MELV strains. Interestingly, the greatest genetic divergence was found for the Gn gene of strain BE AR633512, in which several synonymous and non-synonymous mutations causing changes in RNA secondary structure were observed. Further studies will be necessary to investigate the role of Gn and Gc mutations in the MELV pathogenicity.

A influência da alimentaçäo civilizada na deteriorizaçäo do sistema estomatognático / The influence of the civilized food in the deterioration from stomatognathic system

Num enfoque antropológico e bio-social o autor estabelece um verdadeiro diálogo do passado com o presente, conjeturando que o processo de descaracterizaçäo do sistema estomatognático, face à influência da alimentaçäo civilizada, constituída de dietas moles, exarcebadas a partir da Revoluçäo Industrial, já era perceptível na Idade média com o acelerado processo de abandono do campo e o consequente crescimento das cidades medievais; período em que se assiste também à legitimizaçäo social do estado da miserabilidade . Considera este autor que quase todos os problemas do nosso sistema estomatognático säo originários de atrofia funcional mastigatória, e embasa seus postulados na Teoria da Matriz Funcional, de Melvin Moss, as Leis do Desenvolvimento de Pedro Planas, e as mais recentes pesquisas de Petrovic, McNamara e Moriyón. Num estudo de casos de maloclusäo, observa-se que a distoclusäo sobressai-se sobre as outras maloclusöes por deficiências no aleitamento à peito e a alimentaçäo preponderantemente mole