RESUMO
In order to increase the current density generated in a PEFC (polymer electrolyte fuel cell), a method for measuring the spatial distribution of both the current and the water content of the MEA (membrane electrode assembly) is necessary. Based on the frequency shifts of NMR (nuclear magnetic resonance) signals acquired from the water contained in the MEA using 49 NMR coils in a 7â¯×â¯7 arrangement inserted in the PEFC, a method for measuring the two-dimensional spatial distribution of electric current generated in a unit cell with a power generation area of 140â¯mmâ¯×â¯160â¯mm was devised. We also developed an inverse analysis method to determine the two-dimensional electric current distribution that can be applied to actual PEFC connections. Two analytical techniques, namely coarse graining of segments and stepwise search, were used to shorten the calculation time required for inverse analysis of the electric current map. Using this method and techniques, spatial distributions of electric current and water content in the MEA were obtained when the PEFC generated electric power at 100 A.
Assuntos
Fontes de Energia Elétrica , Eletroquímica/instrumentação , Eletrólitos/química , Espectroscopia de Ressonância Magnética/instrumentação , Polímeros/química , Eletricidade , Eletroquímica/métodos , Eletrodos , Desenho de Equipamento , Espectroscopia de Ressonância Magnética/métodos , Água/químicaRESUMO
We have developed a novel tuberculosis (TB) vaccine; a combination of the DNA vaccines expressing mycobacterial heat shock protein 65 (HSP65) and interleukin 12 (IL-12) delivered by the hemagglutinating virus of Japan (HVJ)-liposome (HSP65+IL-12/HVJ). This vaccine provided remarkable protective efficacy in mouse and guinea pig models compared to the BCG vaccine, on the basis of an induction of the CTL activity and improvement of the histopathological tuberculosis lesions, respectively. Furthermore, we extended our studies to a cynomolgus monkey model, which is currently the best animal model of human tuberculosis. This novel vaccine provided a higher level of the protective efficacy than BCG based upon the assessment of mortality, the ESR, body weight, chest X-ray findings and immune responses. Furthermore, the combination of HSP65+IL-12/HVJ and BCG by the priming-booster method showed a synergistic effect in the TB-infected cynomolgus monkey (100% survival). These data indicate that our novel DNA vaccine might be useful against Mycobacterium tuberculosis for human clinical trials.
Assuntos
Proteínas de Bactérias/imunologia , Chaperoninas/imunologia , Interleucina-12/imunologia , Vacinas contra a Tuberculose/administração & dosagem , Tuberculose/prevenção & controle , Vacinas de DNA/imunologia , Animais , Proteínas de Bactérias/genética , Chaperoninas/genética , Modelos Animais de Doenças , Haplorrinos , Lipossomos/metabolismo , Vírus Sendai , Vacinas contra a Tuberculose/imunologia , Vacinas Sintéticas/imunologiaRESUMO
We have investigated novel vaccine strategies against severe acute respiratory syndrome (SARS) CoV using cDNA constructs encoding the structural antigens: (S), (M), (E), or (N) protein, derived from SARS CoV. PBL from healthy human volunteers were administered i.p. into IL-2 receptor gamma-chain disrupted SCID mice, and SCID-PBL/hu mice were constructed. These mice can be used to analyze the human immune response in vivo. SARS M DNA vaccine and N DNA vaccine induced human CTL specific for SARS CoV antigens. Alternatively, SARS M DNA vaccines inducing human neutralizing antibodies and human monoclonal antibodies against SARS CoV are now being developed. These results show that these vaccines can induce virus-specific immune responses and should provide a useful tool for development of protective and therapeutic vaccines.