Assuntos
Implante Coclear/estatística & dados numéricos , Surdez/epidemiologia , Surdez/cirurgia , Triagem Neonatal/organização & administração , Pessoas com Deficiência Auditiva/reabilitação , Audiologia/organização & administração , Bélgica , Pré-Escolar , Implante Coclear/métodos , Surdez/congênito , Feminino , Humanos , Incidência , Recém-Nascido , Comunicação Interdisciplinar , Masculino , Relações Profissional-Família , Avaliação de Programas e Projetos de Saúde , Melhoria de Qualidade , Medição de Risco , Grupos de Autoajuda , Resultado do TratamentoRESUMO
Brush-border membranes from rat duodenal and jejunal mucosa were prepared by differential Ca(2+)-precipitation. Kinetical properties and Mg(2+)-stimulation of alkaline phosphatase were studied for the enzyme either bound to these membranes or purified from these membranes by liquid chromatography. With p-nitrophenylphosphate as substrate, the alkaline phosphatase apparent Km was lower in jejunum (90 microM) as compared with duodenum (160 microM), and lower for the purified enzyme (jejunum: 55 microM; duodenum: 97 microM) as compared to the bound one. In the presence of 5 mM MgCl2, the substrate affinity was in all cases decreased. For the bound enzyme Vmax was 10 times greater in duodenum compared to jejunum. 5 mM MgCl2 tripled the Vmax of the duodenal bound enzyme and increased it by 50% for the jejunal one, but a seven-fold increase was recorded for the purified enzyme at both levels of intestine. The apparent affinity for Mg2+ was similar for the bound and the free enzyme, for duodenum and for jejunum (Mg0.5: +/- 40 microM).
