RESUMEN
BACKGROUND: The tuberculin skin test (TST) is commonly used for the diagnosis of latent tuberculosis infection (LTBI) in non-bacille Calmette-Guérin (BCG) vaccination settings. In recent years, attention has been drawn to interferon-gamma release assays (IGRAs), especially in BCG-vaccinated populations. In this study, we evaluated the TST and a new whole blood IGRA in BCG-vaccinated individuals during a tuberculosis (TB) outbreak in China. METHODS: A TB outbreak occurred at a university in Dalian, China from March to November 2010. The TST and a whole blood IGRA were used to screen for TB infection. The correlation between exposure levels, TST, and the IGRA were evaluated. RESULTS: We found that agreement between the IGRA and TST was poor (kappa 0.182-0.290). IGRA positivity was associated with the level of exposure, and IGRA positivity and the level of exposure were risk factors for TB incidence. Neither the IGRA nor the TST alone picked up all TB incidences. However, if a 10 mm cutoff for the TST was used in the highest risk exposure group and IGRA positivity was used in the other risk groups, 19 of the 20 (95%) TB cases were identified. CONCLUSIONS: A recommended preventive treatment regimen for China should be based on the level of exposure in conjunction with IGRA and TST test results.
Asunto(s)
Ensayos de Liberación de Interferón gamma/métodos , Adulto , China/epidemiología , Brotes de Enfermedades , Femenino , Humanos , Incidencia , Masculino , Prueba de Tuberculina , Tuberculosis/diagnóstico , Tuberculosis/epidemiología , Tuberculosis/prevención & control , Adulto JovenRESUMEN
A broad range of materials is currently being studied for possible use as the insulating layer in next generation metal-oxide-semiconductor transistors. Inelastic electron tunneling spectroscopy (IETS) has become a powerful tool to characterize both the structural and electrical properties of the resulting device structures made from these materials. IETS can address issues related to reactions and intermixing at interfaces, as well as properties related to carrier mobility, such as phonon modes and charge traps, for structures that are difficult to characterize accurately by other techniques.