Assuntos
Vírus da Encefalite Equina do Leste/efeitos dos fármacos , Vírus da Encefalite Equina Venezuelana/efeitos dos fármacos , Vírus da Encefalite/efeitos dos fármacos , Formaldeído/farmacologia , Metilnitrosoureia/farmacologia , Mutação , Compostos de Nitrosoureia/farmacologia , Genética Microbiana , Mutação/efeitos dos fármacosAssuntos
Vírus da Encefalite/efeitos dos fármacos , Ácido Fusídico/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/farmacologia , Embrião de Galinha , Técnicas de Cultura , Vírus da Encefalite Equina Venezuelana/efeitos dos fármacos , Vírus da Encefalite Equina Venezuelana/crescimento & desenvolvimentoRESUMO
Studies were conducted to determine the effect of nitrogen dioxide (NO(2)) on aerosol survival and biological decay rate of Venezulean equine encephalomyelitis (VEE) virus and spores of Bacillus subtilis var. niger. The NO(2) concentrations used in the experiments were 0.5, 5, and 10 ppm at 24 C and 85% RH. The survival of airborne VEE virus disseminated as particles 1 to 5 mum in diameter was significantly influenced by the presence of 5 ppm of NO(2). At this concentration, the biological decay rate increased threefold and the aerosol recovery and aerosol survival of the VEE virus were significantly lower than at 0.5 ppm or in the absence of NO(2). Airborne spores of B. subtilis were not significantly affected by as much as 10 ppm of NO(2).
Assuntos
Microbiologia do Ar , Bacillus subtilis/efeitos dos fármacos , Vírus da Encefalite/efeitos dos fármacos , Dióxido de Nitrogênio/farmacologia , Aerossóis , Animais , Bacillus subtilis/isolamento & purificação , Embrião de Galinha , Vírus da Encefalite Equina Venezuelana/efeitos dos fármacos , Vírus da Encefalite Equina Venezuelana/isolamento & purificação , Cinética , Esporos Bacterianos/efeitos dos fármacosAssuntos
Ágar/farmacologia , Dextranos/farmacologia , Vírus da Encefalite/efeitos dos fármacos , Polissacarídeos/farmacologia , Protaminas/farmacologia , Replicação Viral/efeitos dos fármacos , Ar , Animais , Embrião de Galinha , Técnicas de Cultura , Vírus da Encefalite Equina Venezuelana/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Íons/farmacologia , Sulfatos/farmacologia , Cultura de VírusRESUMO
Venezuelan equine encephalitis (VEE) virus was purified and concentrated by chromatography of tissue culture supernatant fluids on diethylaminoethyl-cellulose columns. Stepwise gradient elution studies indicated a broad elution pattern for the virus, with recovery occurring from 0.05 to 0.7 m NaCl. Optical density, infectivity, hemagglutination (HA), and complement fixation (CF) assays indicated that complete recovery of input virus in highly purified form was possible. Single-step elution with 0.7 m tris(hydroxymethyl)aminomethane-succinate-salt buffer resulted in a virus volume decrease of 85% with a concomitant increase in infectivity and antigenicity. Recoveries consistently equaled or exceeded 100% of the input preparations. Additional purification of column-recovered virus was obtained by sedimentation of pooled virus eluates on 50% sucrose cushions. Exposure of borate saline and 0.5% histidine suspensions of purified VEE virus preparations to 6 x 10(6) r of gamma radiation resulted in a loss of infectivity for tissue culture and a loss of lethality for weanling and suckling mice. Inactivation was an exponential function of the dosage. In contrast to infectivity, antigencity (HA and CF) of both saline and histidine preparations was retained after irradiation with doses as high as 6 x 10(6) r. Purified and irradiated VEE virus preparations have been successfully used for routine serological tests and are being evaluated as vaccines.