Localized primary melanoma of male urethra with a 4-year follow up.

The objective is to perform a case report of primary melanoma of urethra in a male patient from a Teaching Hospital in Campinas, SP - Brazil. Male, 79 years of age, with blackened lesion on the meatus of the urethra with 1.5 cm of dimension, that could be palpated on the fossa navicularis region associated to an irregular lesion on the region of and the foreskin. The biopsy showed a malignant neoplasia. A partial penectomy with oncological margin of 2 cm was performed with a bilateral deep inguinal linfadenectomy. A follow up showed no recurrence of the disease.

Characterization and evaluation of a recombinant hepatitis B vaccine expressed in yeast defective for N-linked hyperglycosylation.

The hepatitis B (HB) virus preS2 + 2 polypeptide (the M or middle envelope polypeptide) is N-glycosylated at the N4 residue of the preS2 domain when expressed in recombinant yeast. Hyperglycosylation at this amino acid residue (the addition of a large number of mannose residues to the core oligosaccharide), which occurs in common yeast strains, results in an HB vaccine with diminished immunogenicity. Hyperglycosylation can be prevented by expressing the preS2 + S polypeptide in mutant yeast strains (e.g. mnn9) which limit N-linked glycosylation to the addition of only core saccharide residues. An HB vaccine prepared from recombinant yeast expressing the non-hyperglycosylated preS2 + 2 polypeptide was of similar immunogenicity in mice to a licensed HB vaccine and was much more immunogenic in humans than the hyperglycosylated preS2 + 2 vaccine.