RESUMO
The formation of colloidal gold was kinetically studied using the monomer or micelle form of the acetylenic glycol nonionic surfactant Surfynol 465, which functions as a reducing and stabilizing agent. When two equal volumes of aqueous solution of Au(III) and Surfynol 465 were mixed, absorbance at the peak around 300 nm due to Au(III) rapidly decreased with time exponentially. A new peak began to appear around 530 nm, whose height sigmoidally increased with time, showing the formation of colloidal gold. From the variation in absorbance at 300 or 530 nm with time, colloidal gold formation would appear to occur through consecutive first-order reactions, Au(III) --> Au(I) --> Au(0) --> gold particle, for monomer and micelle systems. As for Au(I), the complex between Au(I) and &bond;C&tbond;C&bond; of Surfynol 465 was assigned based on reactions previously proposed for the Raman spectra of colloidal gold (Sato, S., Colloid Polym. Sci. 274, 1161 (1996)). The reaction, Au(0) --> gold particle, proceeded quickly. The overall rate of reaction was slower in the micelle system than in the monomer system. For both systems, the rate constant of the reaction Au(III) --> Au(I) exceeded the constant of the reaction Au(I) --> Au(0), and the activation energies of the two reactions were 58 kJ mol(-1). From the agreement with the activation energy of formation of colloidal gold by another method, consecutive first-order reactions, Au(III) --> Au(I) --> Au(0) --> gold particle, were considered valid for the formation of colloidal gold in the presence of Surfynol 465. Copyright 1999 Academic Press.
Assuntos
Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/isolamento & purificação , Conjuntivite Viral/epidemiologia , Conjuntivite Viral/virologia , Adenovírus Humanos/genética , Túnica Conjuntiva/virologia , Primers do DNA , Humanos , Japão/epidemiologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de RestriçãoRESUMO
The levels of circulating immune complexes (CICs) were investigated in the patients with Behçet's disease by Clq solid-phase enzyme immunoassay. A significantly higher level of CICs was observed in the patients than in the control group. Concerning the correlation between the levels of CICs and the stages of the ocular attack, the levels were significantly higher in the preattack stage and the early stage of the attack than in the late stage and the remission phase. A high level of CICs was associated with the patients of the fulminant form of ocular attacks. These results suggest that immune complexes may play a role in the development of the ocular attack of Behçet's disease.
Assuntos
Complexo Antígeno-Anticorpo/análise , Síndrome de Behçet/imunologia , Adulto , Enzimas Ativadoras do Complemento/análise , Complemento C1q , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
From the study of 18 pregnancies in 10 patients with toxoplasmic retinochoroiditis, it was concluded that the most important factor to be considered in advising pregnant patients with this disease is whether or not the antibody titer increases during pregnancy rather than the clinical pictures or the absolute values of antibody titer. Periodical titration of the antitoxoplasma antibody during pregnancy was recommended as a preventive measure against congenital toxoplasmosis. Pregnancy may be continued if antibody titer does not increase during pregnancy, and it may be interrupted if the antibody titer increases.
