Survey of severe respiratory syncytial virus infection in Kyoto Prefecture from 2003 to 2007.

BACKGROUND: Respiratory syncytial virus (RSV) infection in infants can develop into a severe condition. METHODS: A survey of patients with severe RSV infection in hospitals in Kyoto Prefecture was performed from 2003 to 2007. Patients requiring intubation and those with cardiopulmonary arrest on arrival (CPAOA) were considered to have severe RSV infection. RESULTS: Twenty-five patients with severe infection were identified and detailed data were available for 21 patients, of whom 18 required intubation and three had CPAOA. The male/female ratio was 12/9 and age ranged from 8 days to 19 years (average, 5.2 months; median: 2 months). At admission white blood cell count, lactate dehydrogenase (P < 0.05), and blood glucose (P < 0.01) were higher and Na was lower (P < 0.01) in the 18 patients with severe infection (excluding the CPAOA cases) compared to 18 sex- and age-matched patients with mild RSV infection. The incidence of bacterial infection was also higher in severe cases (P < 0.05). The outcome was death in four patients (19.0%, including two sudden deaths), aftereffects in two (9.5%), hospital discharge with improvement in 14 (66.7%), and an unclear outcome in one patient. Excluding the two sudden death cases, 14 of 19 patients (73.7%) were extubated within 2 weeks. The period of intubation was longer in older patients (P < 0.05). CONCLUSION: Because severe RSV infection led to sudden death in two cases, detection of RSV is important at admission for an infant with CPAOA. Fourteen patients (66.7%), however, had good outcomes and most patients were extubated within 2 weeks.

Visualization and dynamic size evaluation of nanoparticles in solution by single optical fiber-illuminated video microscope analysis.

AIM: It is hoped that nanoparticles will become ever more useful in the development of nanomedicine. To evaluate the behavior of nanoparticles in solution, we aimed to establish a single optical fiber-illumination method that is easy to integrate with a conventional microscope at low cost. METHODS: Solutions of gold nanoparticles and carbon nanotubes were analyzed in a single optical fiber-illuminated video microscope and the tracks of Brownian motion of these nanoparticles were traced using video images. Their diffusion coefficient was measured by the mean square displacement of the movement. Using the diffusion coefficient in the Stokes-Einstein equation, the hydrodynamic diameter of the nanoparticles in solution was evaluated. RESULTS: The visualization of gold nanoparticles clearly in a high signal-to-noise ratio was achieved. The evaluated particle sizes of gold nanoparticles were similar to those obtained by a transmission electron microscope and the aggregation process of the carbon nanotubes following incubation was also observed and similar size estimation of the aggregates was performed. CONCLUSION: The single fiber-illumination method was applicable to visualize nanoparticle movement clearly and to estimate their sizes in solution. This simple method is suitable for the in situ observation of the nanoparticle-binding process to target cells.