Four children with severe mycobacterial infections had a mutation in the gene for interferon-gamma receptor 1 that leads to the absence of receptors on cell surfaces and a functional defect in the up-regulation of tumor necrosis factor alpha by macrophages in response to interferon-gamma. The interferon-gamma pathway is important in the response to intracellular pathogens such as mycobacteria.

Few population-based data exist that describe leisure-time physical activity among pregnant women. The purpose of this study was to characterise the prevalence of leisure activity and to examine characteristics associated with participation in leisure activity during pregnancy. Using data collected from the year 2000 Behavioral Risk Factor Surveillance System, information on leisure activity was collected during telephone interviews from 1979 pregnant women and 44,657 non-pregnant women 18-44 years of age, representative of the US population. The prevalence of any leisure activity in the past month was 65.6%, 95% confidence interval [95% CI] 62.0, 69.1, among pregnant women and 73.1% [95% CI 72.4, 73.9] among non-pregnant women. The prevalence of recommended activity was also lower among pregnant women than non-pregnant women (15.8% vs. 26.1%). The most common leisure activity for pregnant women was walking, followed by activities such as swimming laps, weight lifting, gardening, and aerobics. Among pregnant women, any leisure activity was significantly higher for those with higher education, younger age, and excellent or very good health than for those with fair or poor health. Pregnant women reported less leisure activity than non-pregnant women of the same age. Studies to understand the enablers and barriers to participating in leisure activity during pregnancy are needed.

The built environment may be responsible for making nonmotorized transportation inconvenient, resulting in declines in physical activity. However, few studies have assessed both the perceived and objectively measured environment in association with physical activity outcomes. The purpose of this study was to describe the associations between perceptions and objective measures of the built environment and their associations with leisure, walking, and transportation activity. Perception of the environment was assessed from responses to 1,270 telephone surveys conducted in Forsyth County, NC and Jackson, MS from January to July 2003. Participants were asked if high-speed cars, heavy traffic, and lack of crosswalks or sidewalks were problems in their neighborhood or barriers to physical activity. They were also asked if there are places to walk to instead of driving in their neighborhood. Speed, volume, and street connectivity were assessed using Geographic Information Systems (GIS) for both study areas. Locations of crashes were measured using GIS for the NC study area as well. Objective and perceived measures of the built environment were in poor agreement as calculated by kappa coefficients. Few associations were found between any of the physical activity outcomes and perception of speed, volume, or presence of sidewalks as problems in the neighborhood or as barriers to physical activity in regression analyses. Associations between perceptions of having places to walk to and presence of crosswalks differed between study sites. Several associations were found between objective measures of traffic volume, traffic speed, and crashes with leisure, walking, and transportation activity in Forsyth County, NC; however, in Jackson, MS, only traffic volume was associated with any of the physical activity outcomes. When both objective and perceived measures of the built environment were combined into the same model, we observed independent associations with physical activity; thus, we feel that evaluating both objective and perceived measures of the built environment may be necessary when examining the relationship between the built environment and physical activity.

Certain neighborhood characteristics, particularly trails, and access to places for physical activity may be associated with leisure activity levels. In this study, perceived neighborhood environmental factors and access to places for physical activity were strongly associated with race, education, and income.

No abstract

The descriptive information provided by this study broadens our limited understanding of the prevalence and correlates of walking and bicycling to school in the United States. Further qualitative and quantitative descriptive data are needed to develop successful interventions to increase walking and bicycling to school.

Background-Crime is one aspect of the environment that can act as a barrier to physical activity. The goals of this study were to (1) compare measures of perceived crime with observed crime and (2) examine the association between the independent and combined effects of objective and perceived crime on physical activity.

No abstract