Associations of social cohesion and quality of life with objective and perceived built environments: a latent profile analysis among seniors.

BACKGROUND: Healthy aging requires support from local built and social environments. Using latent profile analysis, this study captured the multidimensionality of the built environment and examined relations between objective and perceived built environment profiles, neighborhood social cohesion and quality of life among seniors. METHODS: In total, 693 participants aged 66-97 were sampled from two US locales in 2005-2008 as part of the Senior Neighborhood Quality of Life Study (SNQLS). Perceived social cohesion and quality of life were assessed using validated surveys. Six objective (geographic information system (GIS)-based) and seven perceived built environment latent profiles generated in previous SNQLS publications were used for analyses. Mixed-effects models estimated social cohesion and quality of life separately as a function of the built environment profiles. RESULTS: More walkable and destination-rich perceived built environment profiles were associated with higher social cohesion and quality of life. Objective built environment profiles were not associated with social cohesion and only positively associated with quality of life in only one locale (Baltimore/DC). CONCLUSIONS: Latent profile analysis offered a comprehensive approach to assessing the built environment. Seniors who perceived their neighborhoods to be highly walkable and recreationally dense experienced higher neighborhood social cohesion and quality of life, which may set the stage for healthier aging.

Where and when adolescents are physically active: Neighborhood environment and psychosocial correlates and their interactions.

Female adolescents are less active than male peers in certain contexts including the neighborhood. Adolescents' physical activity can be explained by interactions between environmental and psychosocial factors, but few studies have tested such interactions in relation to context-specific behaviors. This study tested interactions between neighborhood environmental and psychosocial factors in relation to adolescents' context-specific physical activity. Data were collected in 2009-11 from 910 adolescents and a parent/guardian residing in the Baltimore/Seattle regions. Measures included adolescent-reported neighborhood leisure-time physical activity (LTPA) and non-neighborhood LTPA, accelerometer-based non-school moderate-to vigorous-physical activity (MVPA), psychosocial factors, and objective and parent-perceived neighborhood environmental factors. Gender-stratified mixed effects linear models tested associations of 6 environmental and 4 psychosocial factors and their interactions in relation to each physical activity outcome. The psychosocial factors had consistent associations with the physical activity outcomes but the environmental correlates were context-specific. Decisional balance (weighing of pros and cons of physical activity) moderated the association between recreation facility density and neighborhood LTPA among females, with a negative association only among those with high decisional balance (pros outweighed cons). Decisional balance also moderated associations of neighborhood walkability with non-school MVPA among females and non-neighborhood LTPA among males, with positive associations only among those with high decisional balance. Results support context-specific ecological models of physical activity. Targeting environmental factors that may promote opportunities for physical activity in specific contexts as well as adolescent decision-making may help promote their physical activity in those contexts, potentially leading to increased overall physical activity.

Interactions between individual and perceived environmental factors on Latinas' physical activity.

Background: Latinas have disproportionately low levels of physical activity (PA) and the ecological correlates of their PA remain unclear. This study aims to test interactions between individual and environmental factors on Latinas' PA. Methods: We analyzed baseline data from 436 Latinas participating in a PA randomized controlled trial in San Diego, CA [Fe en Acción/Faith in Action]. Measures included demographics, perceived environment, PA and anthropometrics. Mixed effects models examined interactions between individual and environmental factors on self-reported leisure-time and transportation, and accelerometer-assessed PA. Results: Significant positive associations were found between neighborhood aesthetics and leisure-time moderate-to-vigorous PA (MVPA) and between having destinations within walking distance from home and transportation PA (P < 0.05). We found significant interactions of income with aesthetics and sidewalk maintenance as well as between weight status and safety from crime. Favorable aesthetics was related to more leisure-time MVPA only among lower income women (odds ratio (OR) = 1.57; 95% confidence interval (CI): 1.18, 2.08); however, higher income women reporting better sidewalk maintenance reported more leisure-time MVPA (OR = 1.51; 95% CI: 1.06, 2.15). Higher perceived safety from crime was positively related to transportation PA only among overweight/obese women. Conclusions: Subgroup differences should be considered when developing interventions targeting the neighborhood environment to promote Latinas' PA.

Active school transport and fast food intake: Are there racial and ethnic differences?

OBJECTIVES: To investigate whether active school transport was associated with fast food consumption, and to examine differences across racial/ethnic groups. METHODS: Adolescent data (n=3194) from the 2009 California Health Interview Survey were analyzed with logistic regression models to examine the association between active school transport (AST) and fast food intake across racial/ethnic groups. RESULTS: In the overall sample, AST during 1-2days in the past week was associated with greater likelihood of fast food intake (OR: 1.58; 95% CI: 1.03-2.43), compared with zero days of AST, controlling for demographic and other factors. The association between AST and fast food intake differed significantly by race/ethnicity (p<0.01). Among Latino adolescents, greater frequency of AST was significantly associated with greater likelihood of fast food intake (1-2days OR, 2.37, 95%CI: 1.05-5.35; 3-4days OR, 2.78, 95% CI: 1.04-7.43; 5days OR, 2.20, 95%CI: 1.23-3.93). Among White and Asian adolescents, there was a curvilinear pattern: relative to adolescents who reported zero days of AST, those who did AST 1-2days/week had greater likelihood of fast food intake, but AST of 3-4days and 5days/week was associated respectively, with higher and lower likelihood of fast food intake among both groups. CONCLUSIONS: AST appears to be a risk factor for fast food intake, and may expose some ethnic groups more than others to increased opportunity to purchase and consume fast food. Programs and policies to promote AST among adolescents should incorporate efforts to encourage healthy eating and discourage concentration of fast food outlets near schools.

International study of objectively measured physical activity and sedentary time with body mass index and obesity: IPEN adult study.

BACKGROUND: Physical activity (PA) has been consistently implicated in the etiology of obesity, whereas recent evidence on the importance of sedentary time remains inconsistent. Understanding of dose-response associations of PA and sedentary time with overweight and obesity in adults can be improved with large-scale studies using objective measures of PA and sedentary time. The purpose of this study was to examine the strength, direction and shape of dose-response associations of accelerometer-based PA and sedentary time with body mass index (BMI) and weight status in 10 countries, and the moderating effects of study site and gender. METHODS: Data from the International Physical activity and the Environment Network (IPEN) Adult study were used. IPEN Adult is an observational multi-country cross-sectional study, and 12 sites in 10 countries are included. Participants wore an accelerometer for seven consecutive days, completed a socio-demographic questionnaire and reported height and weight. In total, 5712 adults (18-65 years) were included in the analyses. Generalized additive mixed models, conducted in R, were used to estimate the strength and shape of the associations. RESULTS: A curvilinear relationship of accelerometer-based moderate-to-vigorous PA and total counts per minute with BMI and the probability of being overweight/obese was identified. The associations were negative, but weakened at higher levels of moderate-to-vigorous PA (>50 min per day) and higher counts per minute. No associations between sedentary time and weight outcomes were found. Complex site- and gender-specific findings were revealed for BMI, but not for weight status. CONCLUSIONS: On the basis of these results, the current Institute of Medicine recommendation of 60 min per day of moderate-to-vigorous PA to prevent weight gain in normal-weight adults was supported. No relationship between sedentary time and the weight outcomes was present, calling for further examination. If moderator findings are confirmed, the relationship between PA and BMI may be country- and gender-dependent, which could have important implications for country-specific health guidelines.

The development of a walkability index: application to the Neighborhood Quality of Life Study.

Emerging evidence supports a link between neighbourhood built environment and physical activity. Systematic methodologies for characterising neighbourhood built environment are needed that take advantage of available population information such as census-level demographics. Based on transportation and urban planning literatures, an integrated index for operationalising walkability using parcel-level information is proposed. Validity of the walkability index is examined through travel surveys among areas examined in the Neighborhood Quality of Life Study (NQLS), a study investigating built environment correlates of adults' physical activity.

Adenosine triphosphate-deficient erythrocytes of the egg-laying mammal, echidna (tachyglossus aculeatus).

The erythrocytes of the short-beaked echidna (Tachyglossus aculeatus), an egg-laying mammal, were examined for the presence of phosphorylated compounds. The erythrocytes contained only 0.03 +/- 0.01 micromoles of adenosine 5'-triphosphate per milliliter of cells. This amount is two orders of magnitude less than that in human cells. Although the echidna erythrocytes had an abundance of 2,3-diphosphoglycerate and other glycolytic intermediates, no other energy-rich pyridine and purine compounds were detected.

The role of primary care in promoting children's physical activity.

Regular physical activity enhances health during childhood and adolescence and is important in setting the stage for participation in physical activity across the lifespan. Physician-patient interactions during childhood and adolescence provide important opportunities for clinicians to influence physical activity behaviours. This article reviews current physical activity recommendations for youth and the wide range of health benefits provided to youth from engaging in regular physical activity. It also outlines a practical counselling model, the 5As approach, that can guide clinical counselling for physical activity, and reviews how an increasingly important model of practice organisation, the Care Model, can be used to promote physical activity in children and adolescents. Family, social and environmental influences on child and adolescent physical activity are also addressed.

Food outlet visits, physical activity and body weight: variations by gender and race-ethnicity.

PURPOSE: Recent evidence documents significant associations between community design, physical activity and obesity when adjusting for demographic covariates. Yet it is well understood that energy imbalance and weight gain are also a function of dietary patterns, and perhaps the degree of access to healthy food choices. METHODS: The current study builds upon the Atlanta-based SMARTRAQ study of over 10,000 respondents and reports an integrated assessment of obesity impacts of physical activity and food outlet visitation. Respondents in the SMARTRAQ survey aged 25-65 provided BMI, self-reported physical activity levels (IPAQ), demographic factors, and where they went for food over a 2 day period. RESULTS: The relative effect of physical activity, neighbourhood walkability, and food outlet visitation on BMI differed significantly across gender and ethnicity. BMI in females increased with fast food and decreased with grocery store visitation and physical activity, but not with walkability or walking. BMI in males was not related to where they went for food but decreased with walking and overall physical activity and with walkability. Fast food visitation was associated with increased BMI in white respondents and grocery store visitation with decreased BMI in black respondents. Meeting moderate activity guidelines was associated with lower BMI in both black and white respondents, yet walking was only significant in predicting reduced BMI in white respondents. CONCLUSION: Obesity influences of physical activity, walkability, and where people go for food differ significantly across gender and ethnicity and offer important policy implications and insights for future research.

Validating stage of change measures for physical activity and dietary behaviors for overweight women.

OBJECTIVE: To investigate the construct, concurrent and predictive validity of stage of change measures for physical activity (PA), and intakes of fruit and vegetables (FVs), dietary fiber (FB) and dietary fat (DF) among a sample of overweight women. DESIGN: Subjects were 401 women (mean age=41, s.d.=8.7 years; mean body mass index=32.35, s.d.=4.6) recruited to participate in a 12-month weight loss intervention trial. Concurrent validity tests included (1) self-report of current behavior, (2) decisional balance (for example, pros and cons of behavior change), (3) self-efficacy, (4) the MTI Actigraph accelerometer (for the PA staging measure), and (5) a food-frequency questionnaire (for all dietary staging measures). Predictive validity was assessed through tests of the relationship between the baseline stage of change measures and their corresponding behavior 1-year later. RESULTS: Coefficient alpha-tests of internal consistency exceeded 0.70 on the majority of scales. Concurrent validity tests indicated strong validity evidence for three staging measures and little validity for the DF staging measure (eta(2) range, 0.02-0.18). All staging algorithms demonstrated predictive validity (eta(2) range, 0.04-0.126). CONCLUSION: Staging measures can determine motivational readiness for overweight women, contribute to the standardization of stage of change assessment and facilitate cross-study comparisons.

Perceived Neighborhood Environmental Factors That Maximize the Effectiveness of a Multilevel Intervention Promoting Physical Activity Among Latinas.

PURPOSE: This study tested whether a multilevel physical activity (PA) intervention had differential effects on PA according to participants' perceptions of their neighborhood environment. DESIGN: Two-group cluster randomized controlled trial. SETTING: San Diego, California. SUBJECTS: Analytical sample included 319 Latinas (18-65 years) from churches randomized to the following conditions: PA (n = 8 churches, n = 157 participants) or attention control (n = 8 churches, n = 162 participants). INTERVENTION: Over 12 months, PA participants were offered free PA classes (6/wk), while attention control participants were offered cancer prevention workshops. MEASURES: Baseline and 12-month follow-up measures included self-report and accelerometer-based moderate to vigorous physical activity (MVPA), sociodemographics, and perceived neighborhood environment variables. ANALYSIS: Mixed-effects models examined each PA outcome at 12-month follow-up, adjusted for church clustering, baseline PA, and sociodemographics. We tested interactions between 7 baseline perceived environment variables and study condition. RESULTS: Neighborhood esthetics was the only significant moderator of intervention effects on accelerometer-based MVPA and self-report leisure-time MVPA. Participants in the PA intervention had significantly higher PA at follow-up than attention control participants, only when participants evaluated their neighborhood esthetics favorably. CONCLUSION: Perceived neighborhood esthetics appeared to maximize the effectiveness of a multilevel PA intervention among Latinas. For sustainable PA behavior change, the environments in which Latinas are encouraged to be active may need to be evaluated prior to implementing an intervention to ensure they support active lifestyles.

A research agenda to guide progress on childhood obesity prevention in Latin America.

Childhood obesity rates in Latin America are among the highest in the world. This paper examines and evaluates the many efforts underway in the region to reduce and prevent further increases in obesity, identifies and discusses unique research challenges and opportunities in Latin America, and proposes a research agenda in Latin America for the prevention of childhood obesity and concomitant non-communicable diseases. Identified research gaps include biological challenges to healthy growth across the life cycle, diet and physical activity dynamics, community interventions promoting healthy child growth, and rigorous evaluation of national food and activity programs and regulatory actions. Addressing these research gaps is critical to advance the evidence-based policy and practice in childhood obesity tailored to the Latin American context that will be effective in addressing obesity.

Specific inhibition of basic calcium phosphate and calcium pyrophosphate crystal-induction of metalloproteinase synthesis by phosphocitrate.

Calcium pyrophosphate dihydrate (CPPD) and basic calcium phosphate (BCP) crystal deposition diseases are a group of heterogeneous arthritides which are a significant source of morbidity in the elderly. Both crystals induced mitogenesis and metalloproteinase (MP) synthesis and secretion by fibroblasts and chondrocytes which may promote degradation of intra-articular tissue. We have previously shown that phosphocitrate (PC), an inhibitor of hydroxyapatite crystallization, specifically blocks BCP crystal-induced mitogenesis in 3T3 cells. This led us to examine the effect of PC on BCP and CPPD crystal induction of MP synthesis in human fibroblasts. PC (10(-3) to 10(-4) M) specifically inhibited the crystal-induced collagenase and stromelysin mRNA accumulation while having no effect on epidermal growth factor-induced or basal levels of mRNA for both enzymes. Western blots (collagenase) of conditioned media confirmed that PC blocked crystal-induced proteinase secretion as well. Moreover, PC (10(-3) M) also blocked the crystal induction of c-fos and c-jun. Since FOS and JUN proteins form a transacting activator (AP-1) for expression of collagenase and stromelysin genes, PC may block the synthesis of both enzymes by inhibiting the transcription of c-fos and c-jun.

Behavioral science research in diabetes: lifestyle changes related to obesity, eating behavior, and physical activity.

Lifestyle factors related to obesity, eating behavior, and physical activity play a major role in the prevention and treatment of type 2 diabetes. In recent years, there has been progress in the development of behavioral strategies to modify these lifestyle behaviors. Further research, however, is clearly needed, because the rates of obesity in our country are escalating, and changing behavior for the long term has proven to be very difficult. This review article, which grew out of a National Institute of Diabetes and Digestive and Kidney Diseases conference on behavioral science research in diabetes, identifies four key topics related to obesity and physical activity that should be given high priority in future research efforts: 1) environmental factors related to obesity, eating, and physical activity; 2) adoption and maintenance of healthful eating, physical activity, and weight; 3) etiology of eating and physical activity; and 4) multiple behavior changes. This review article discusses the significance of each of these four topics, briefly reviews prior research in each area, identifies barriers to progress, and makes specific research recommendations.

Independent and combined influence of neonatal and current body composition on academic performance in youth: The UP & DOWN Study.

BACKGROUNDS: Unhealthy body composition is a cause for concern across the lifespan. OBJECTIVE: The objective of this study was to examine the independent and combined associations between neonatal and current body composition with academic performance among youth. METHODS: This cross-sectional study was conducted with a total of 1557 youth (745 girls) aged 10.4 ± 3.4 years. Birth weight and length at birth were self-reported. Current body composition was assessed by body mass index (BMI), waist circumference (WC) and percentage of body fat (BF%). Academic performance was assessed through schools records. RESULTS: Birth weight was related to all academic variables in boys, independent of potential confounders, including BMI; whereas WC, BMI and BF% were related to all academic performance indicators in both boys and girls, independent of potential confounders, including birth weight (all P < 0.05). In addition, the combined adverse effects of low birth weight and current overweight on academic performance were observed in both boys and girls for grade point average (GPA) indicator. Boys in the group with none adverse effect had significantly higher scores in GPA (score +0.535; 95% confidence interval, 0.082-0.989) than boys in the group of both adverse effects (P < 0.007); among girls, GPA score was higher in the group with none adverse effect than in the groups with one or two adverse effects (P for trend = 0.029). CONCLUSIONS: Neonatal and current body composition, both independently and combined, may influence academic performance in youth.

Metabolic properties of low ATP erythrocytes of the monotremes.

The erythrocytes of the monotremes, having a trace amount of ATP, can metabolize glucose to lactate at a rate comparable to human and other mammalian erythrocytes. The echidna energy metabolism is unique in that adenosine can stimulate glycolytic carbon flow, resulting in a nearly 20-fold net synthesis of ATP.

Physical activity assessment in American Indian schoolchildren in the Pathways study.

The objective of the Pathways physical activity feasibility study was to develop methods for comparing type and amount of activity between intervention and control schools participating in a school-based obesity prevention program. Two methods proved feasible: 1) a specially designed 24-h physical activity recall questionnaire for assessing the frequency and type of activities and 2) use of a triaxial accelerometer for assessing amount of activity. Results from pilot studies supporting the use of these methods are described. Analyses of activity during different segments of the day showed that children were most active after school. The activities reported most frequently (e.g., basketball and mixed walking and running) were also the ones found to be most popular in the study population on the basis of formative assessment surveys. Both the physical activity recall questionnaire and the triaxial accelerometer methods will be used to assess the effects of the full-scale intervention on physical activity.

Phosphocitrate and its analogue N-sulpho-2-amino tricarballylate inhibit aortic calcification.

This study reports the ability of phosphocitrate and its enzyme-resistant analogue N-sulpho-2-amino tricarballylate to inhibit aortic calcification. Dystrophic calcification of aorta was induced by transplanting fresh aortic segments in Millipore chambers to the peritoneal walls of recipient rats. Daily intraperitoneal injection of the new inhibitors remarkably reduced calcium accumulation by the aortae and prevented the appearance of hydroxyapatite-like crystalline structures. Phosphocitrate was the most effective of the anti-calcifying agents tested, preventing aortic calcification at 1 mumole/day/rat. N-sulpho-2-amino tricarballylate was less effective, reducing aortic calcification by 60% at 10 mumoles/day/rat. The new inhibitors might prove therapeutically useful in man to arrest soft tissue calcification.

A possible antiatherogenic role for phosphocitrate through modulation of low density lipoprotein uptake and degradation in aortic smooth muscle cells.

The present study reports the influence of a phosphorylated polycarboxylic acid, phosphocitrate, on low density lipoprotein (LDL) metabolism in cultured rabbit aortic smooth muscle cells. Phosphocitrate profoundly influenced both LDL binding and degradation. At the maximal effective concentration (2 mM), phosphocitrate released approximately 90% of the receptor-bound [125I]LDL whilst the total amount of [125I]LDL degraded was reduced by 60%. Measurement of total cholesterol accumulation revealed that even in the presence of high concentrations of added LDL, phosphocitrate (2 mM) diminished cholesterol levels close to the basal levels seen in incubations in lipoprotein-deficient serum. Further, this inhibitory effect of phosphocitrate was demonstrable after 24 h at 37 degrees C. Phosphocitrate, a recognized anticalcifying agent, possesses a strong negative charge to size ratio at physiological pH. It is postulated that the observed effects probably arise from charge interference and/or its ability to modulate cellular calcium concentration.