LED fluorescence microscopy in the diagnosis of tuberculosis: Fading and restaining of smears for external quality assessment

AbstractBlinded rechecking is a method proposed for external quality assurance (EQA) of auramine-stained acid-fast bacilli (AFB) smears using fluorescence microscopy (FM), however, this procedure is not well developed and slides fading over time could compromise its implementation. Since bleaching of fluorescent molecules involves temperature-dependent chemical reactions, it is likely that low temperatures could slow down this process. We stored auramine-stained slides under different environmental conditions, including −20°C, and examined them over time. The slides stored in all the environments faded. At −20°C, fading was not reduced in relation to room temperature. Restaining and re-examining smears after five months showed that the slides containing saliva and storage at −20°C were associated with failure in AFB reappearance. In conclusion, the practice of freezing slides until they are viewed should be discouraged as it has a negative effect on blinded rechecking by reducing reading concordance after restaining. Specimen quality should be considered when interpreting FM-EQA results

El aprendizaje autónomo de lenguas en tándem : principios, estrategias y experiencias de integración

Recopilación de artículos dirigidos a profesores de lenguas, asesores lingüísticos y a aquellos que deseen organizar y apoyar el aprendizaje autónomo de lenguas en tándem. Se recogen las principales claves teóricas de dicho modelo de aprendizaje, incluyendo consideraciones sobre los principios que lo rigen, las estrategias que le son de aplicación y la eficacia de su uso. Se proporcionan consejos prácticos que pueden servir de ayuda a los interesados en acercarse a las características de este método, ya sea desde una perspectiva investigadora o con el deseo de organizar experiencias de aprendizaje autónomo similares.AsturiasBiblioteca de Educación del Ministerio de Educación, Cultura y Deporte; Calle San Agustín 5 -3 Planta; 28014 Madrid; Tel. +34917748000; [email protected]