Running reduces stress and enhances cell genesis in aged mice

Cell proliferation and neurogenesis are diminished in the aging mouse dentate gyrus. However, it is not known whether isolated or social living affects cell genesis and stress levels in old animals. To address this question, aged (17–18 months old) female C57Bl/6 mice were single or group housed, under sedentary or running conditions. We demonstrate that both individual and socially housed aged C57Bl/6 mice have comparable basal cell proliferation levels and demonstrate increased running-induced cell genesis. To assess stress levels in young and aged mice, corticosterone (CORT) was measured at the onset of the active/dark cycle and 4 h later. In young mice, no differences in CORT levels were observed as a result of physical activity or housing conditions. However, a significant increase in stress in socially housed, aged sedentary animals was observed at the onset of the dark cycle; CORT returned to basal levels 4 h later. Together, these results indicate that voluntary exercise reduces stress in group housed aged animals and enhances hippocampal cell proliferation.     

Rotarix®: vaccine performance 6 years postlicensure

Rotarix(?) was first licensed in 2004 and rapidly introduced into private and public markets worldwide. In a previous 2009 article, we reviewed the impact of rotavirus-associated disease, the rationale for different vaccines, prelicensure efficacy studies and cost-effectiveness studies for Rotarix. As of September 2011, Rotarix had been licensed in 123 countries in the Americas, Europe, Australia, Africa and Asia, of which 27 have incorporated the vaccine into national or regional immunization programs. The current review intends to provide the reader with further insight into this vaccine, focusing mainly on the new information obtained after a 6-year postlicensure period. This review will provide only a brief summary of prelicensure studies extensively discussed in the previous publication and refer, in more depth, to the worldwide experience with the vaccine, vaccine impact, and safety observed in effectiveness and observational studies, including a particular analysis on protection against rotavirus G2P[4].     

Infectious Aerosol Capture Mask as Environmental Control to Reduce Spread of Respiratory Viral Particles

Negative pressure isolation of COVID-19 patients is critical to limiting the nosocomial transmission of SARS-CoV-2; however, airborne isolation rooms are limited. Alternatives to traditional isolation procedures are needed. The evaluation of an Infectious Aerosol Capture Mask (IACM) that is designed to augment the respiratory isolation of COVID-19 patients is described. Efficacy in capturing exhaled breath aerosols was evaluated using laboratory experimentation, computational fluid dynamics (CFD) and measurements of exhaled breath from COVID-19 patients and their surroundings. Laboratory aerosol experiments indicated that the mask captured at least 99% of particles. Simulations of breathing and speaking showed that all particles between 0.1 and 20 µm were captured either on the surface of the mask or in the filter. During coughing, no more than 13% of the smallest particles escaped the mask, while the remaining particles collected on the surfaces or filter. The total exhaled virus concentrations of COVID-positive patients showed a range from undetectable to 1.1 × 10⁶ RNA copies/h of SARS-CoV-2, and no SARS-CoV-2 aerosol was detected in the samples collected that were adjacent to the patient when the mask was being worn. These data indicate that the IACM is useful for containing the exhaled aerosol of infected individuals and can be used to quantify the viral aerosol production rates during respiratory activities.