Leukoencephalitis and vasculitis with perivascular demyelination in a Weimaraner dog.

Aseptic and noninfectious diseases of the central nervous system are being recognized with increasing frequency. After multiple episodes of neurologic illness, this 7-year-old Weimaraner dog was euthanatized and submitted for postmortem examination. Lesions in the central nervous system were found mainly in the white matter of the cerebral cortex and cervical spinal cord and represented acute and more chronic injury. Necrotizing vasculitis with fibrinoid change and a marked neutrophilic infiltrate dominated the acute lesions. More chronic changes consisted of perivascular demyelination and accumulation of foamy macrophages with positive staining for myelin. An immune-complex (Arthus-type) vasculitis is suspected.

DNA vaccines.

The use of DNA and mRNA as vectors for immunization is a relatively recent development in the field of vaccines. The first paper demonstrating the efficacy of a DNA vaccine in an animal model of viral disease was published in 1993 (1). The rationale for using nucleic acids as vaccines came from the Initial observations that mtramuscular (im) injection of nonrephcating plasmid DNA expression vectors or mFWA-encoding reporter genes could result in the in vivo expression of proteins in mouse muscle cells (2). This ability to express proteins in vivo offers the opportunity to generate immune responses against foreign antigens encoded by the nucleic acid. In addition, both humoral and cell-mediated immune (CMI) responses, such as cytotoxic T-lymphocytes (CTL), can be induced. In general, CTL responses require endogenous expression of the antigen, such as during immunization with live viruses or replicating vectors, whereas subunit protein, polysaccharide conjugate, or inactivated virus vaccines generate humoral immune responses, but not CTL. Therefore, the technique of DNA injection has potential advantages over certain other vaccine technologies.

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.

Efeito da massa e composiçäo corporal sobre a produçäo de potência média no teste de Wingate / The effect of body mass and body composition on mean power output in the Wingate test

O objetivo deste estudo foi o de examinar o efeito da composiçäo e massa corporais sobre a produçäo de potência média no teste de Wingate com duraçäo de 30 segundo e cinco diferentes cargas de resistência. Quarenta indivíduos do sexo feminino (idade média de 22 anos) foram divididos em quatro grupos baseados na massa corporal e soma de cinco dobras cutâneas. O teste de Wingate foi realizado com cinco cargas de resistência: 0,075, 0,080, 0,090 e 0,095 Kp/Kg do peso corporal. Uma 3-way ANOVA (massa, dobras cutâneas e crgas de resistência) mostrou que: (1) a potência média (W/Kg) foi similar para grupos de baixa e alta massa; (2) o grupo com baixa soma de dobras cutâneas apresentou uma produçäo de potência média significantemente maior (p < 0,02) do que o grupo com alta soma de dobras cutâneas; (3) o grupo com baixa soma de dobras cutâneas mostrou um valor de potência média mais alto (p < 0,05) do que o grupo com alta soma de dobras cutâneas para qeuivalentes cargas de resistência