Molecular and phenotypic characterization of Escherichia coli O26:H8 among diarrheagenic E. coli O26 strains isolated in Brazil.

Escherichia coli strains of serogroup O26 comprise two distinct groups of pathogens, characterized as enteropathogenic E. coli (EPEC) and enterohemorrhagic E. coli (EHEC).

Involvement of regulatory T cells in HIV immunopathogenesis.

Recently, a mechanism of negative regulation of immune responses by a specialized population of so-called regulatory T cells (Tregs) has become a focus of intense investigation. Through the discovery of transcription factor Foxp3 as a central molecular determinant of Tregs differentiation and function, the complex biology of these cells, including maintenance of immunological tolerance to "self" and regulation of immune responses to pathogens, commensals, and tumors, has become the focus of intense investigation. The ability to control the infection and to delay the progression of the infection to AIDS and/or death is probably regulated by a balance between host factors, such as immunologic response and viral factors.

A new method for asperphenamate synthesis and its antimicrobial activity evaluation.

Asperphenamate is a natural phenylalanine derivative. This compound was produced through a new, two-step synthetic route. It was also evaluated by the antimicrobial activity of the pure substance against Escherichia coli, Staphylococcus aureus and Cladosporium herbarum.

Antimicrobial activity and chemical investigation of Brazilian Drosera.

The antimicrobial activity of three different extracts (hexanic, ethyl acetate, methanol) obtained from Brazilian Drosera species (D. communis, D. montana var.

Genotypic and phenotypic characterization of attaching and effacing Escherichia coli (AEEC) isolated from children with and without diarrhoea in Londrina, Brazil.

Attaching and effacing Escherichia coli (AEEC) have been implicated in diarrhoea in humans in several countries. A total of 919 E. coli strains, isolated from 125 children with diarrhoea and 98 without diarrhoea, was investigated by PCR for the presence of the EAF, bfp, eae and stx genes.