RESUMO
Lignolytic enzymes such as laccase have been difficult to over-express in an active form. This paper describes the expression, characterization, and application of a fungal laccase in maize seed. The transgenic seed contains immobilized and extractable laccase. Fifty ppm dry weight of aqueously extractable laccase was obtained, and the remaining solids contained a significant amount of immobilized laccase that was active. Although a portion of the extractable laccase was produced as inactive apoenzyme, laccase activity was recovered by treatment with copper and chloride. In addition to allowing the apoenzyme to regain activity, treatment with copper also provided a partial purification step by precipitating other endogenous corn proteins while leaving >90% of the laccase in solution. The data also demonstrate the application of maize-produced laccase as a polymerization agent. The apparent concentration of laccase in ground, defatted corn germ is approximately 0.20% of dry weight.
Assuntos
Lacase/genética , Lacase/isolamento & purificação , Polyporales/enzimologia , Sementes/enzimologia , Zea mays/genética , Apoenzimas/isolamento & purificação , Apoenzimas/metabolismo , Cloretos/metabolismo , Cobre/metabolismo , Proteínas Fúngicas/genética , Lacase/biossíntese , Lignina/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Polyporales/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Zea mays/enzimologiaRESUMO
OBJECTIVE: The aim of this study was to assess the efficacy of a behavioral treatment program for achieving initial cocaine abstinence in individuals enrolled in outpatient treatment for cocaine dependence. METHOD: Thirteen consecutively admitted outpatients were offered behavioral treatment consisting of contingency management procedures and the community reinforcement approach. Fifteen consecutively admitted outpatients were offered treatment with 12-step counseling. All 13 of the patients who were offered the behavioral treatment accepted it; 12 of the patients offered 12-step counseling accepted it. RESULTS: Eleven of the 13 patients in the behavioral treatment were retained for 12 weeks of treatment, compared with five of the 12 patients given 12-step counseling. Ten of the patients given behavioral therapy achieved 4 weeks of continuous cocaine abstinence, compared with only three of those given 12-step counseling. Six of the patients in the behavioral treatment group achieved 8 weeks, and three achieved 12 weeks; none of the patients in the 12-step counseling program achieved 8 weeks. CONCLUSIONS: The behavioral treatment described in this paper offers promise as an effective intervention for achieving initial cocaine abstinence. A randomized trial is underway to assess the generality of these findings.
Assuntos
Terapia Comportamental/métodos , Cocaína , Transtornos Relacionados ao Uso de Substâncias/terapia , Adulto , Assistência Ambulatorial , Atitude Frente a Saúde , Aconselhamento , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Pacientes Desistentes do Tratamento , Projetos Piloto , Reforço Psicológico , Reforço Social , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Transtornos Relacionados ao Uso de Substâncias/psicologia , Fatores de TempoRESUMO
Two males diagnosed with cocaine dependence received a behavioral intervention comprised of contingency management and the community reinforcement approach. During the initial phase of treatment, reinforcement was delivered contingent on submitting cocaine-free urine specimens. The community reinforcement approach involved two behavior therapy sessions each week. Almost complete cocaine abstinence was achieved, but regular marijuana use continued. During a second phase, reinforcement magnitude was reduced, but remained contingent on submitting cocaine-free specimens. Behavior therapy was reduced to once per week. Cocaine abstinence and regular marijuana use continued. Next, reinforcement was delivered contingent on submitting cocaine- and marijuana-free specimens. This modified contingency resulted in an abrupt increase in marijuana abstinence and maintenance of cocaine abstinence. One- and 5-month follow-ups indicated that cocaine abstinence continued, but marijuana smoking resumed. These results indicate that the behavioral intervention was efficacious in achieving abstinence from cocaine and marijuana; maintenance, however, was achieved for cocaine only.
Assuntos
Terapia Comportamental/métodos , Cocaína , Abuso de Maconha/reabilitação , Esquema de Reforço , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adulto , Seguimentos , Humanos , Masculino , Abuso de Maconha/psicologia , Reforço Social , Apoio Social , Transtornos Relacionados ao Uso de Substâncias/psicologiaRESUMO
Beef calves were inoculated with bovine adenovirus-3 or infectious bovine rhinotracheitis virus. After inoculation, plasma fibrinogen increased, serum phosphorus decreased, and nitrogen and phosphorus digestibility decreased compared with preinoculation values. Urinary N excretion increased when calves developed rectal temperatures greater than 39.7 C. Results indicated that clinical infection of calves with infectious bovine rhinotracheitis virus increases urinary N excretion and reduces N and phosphorus balance, and that clinical and subclinical infections with either virus reduce dietary N digestibility.
