Chronic arsenic exposure affects stromal cells and signaling in the small intestine in a sex-specific manner.

Arsenic is a toxicant that is ingested through drinking water and food, exposing nearly 140 million people to levels above the 10 ppb guideline concentration. Studies have shown that arsenic affects intestinal stem cells (ISCs), but the mechanisms by which arsenic alters the formation of adult cells in the small intestine are not well understood. Signals derived from intestinal stromal cells initiate and maintain differentiation. The goal of this study is to evaluate arsenic's effect on intestinal stromal cells, including PdgfrαLo trophocytes, located proximal to the ISCs, and PdgfrαHi telocytes, located proximal to the transit-amplifying region and up the villi. Adult Sox9tm2Crm-EGFP mice were exposed to 0, 33, and 100 ppb sodium arsenite in their drinking water for 13 weeks, and sections of duodenum were examined. Flow cytometry indicated that arsenic exposure dose-responsively reduced Sox9+ epithelial cells and trended toward increased Pdgfrα+ cells. The trophocyte marker, CD81, was reduced by 10-fold and 9.0-fold in the 100 ppb exposure group in male and female mice, respectively. Additionally, a significant 2.2- to 3.1-fold increase in PdgfrαLo expression was found in male mice in trophocytes and Igfbp5+ cells. PdgfrαHi protein expression, a telocyte marker, was more prevalent along the villus/crypt structure in females, whereas Gli1 expression (telocytes) was reduced in male mice exposed to arsenic. Principle coordinate analysis confirmed the sex-dependent response to arsenic exposure, with an increase in trophocyte and decrease in telocyte marker expression observed in male mice. These results imply that arsenic alters intestinal mesenchymal cells in a sex-dependent manner.

An evaluation of the EASY instrument in a cross-sectional study.

BACKGROUND: The purpose of this paper is to evaluate the impact of modifying the published scoring system to address identified potential weaknesses in the published scoring system for the Evaluation of Activity Surveys in Youth (EASY). A secondary purpose was to evaluate the EASY on children in Grades 1-5. The EASY is a self-report physical activity instrument for youth. METHODS: Original EASY survey results were collected at one time point from an online panel from participants across the United States as part of a larger cross-sectional University of Minnesota project looking at children's specific activity and sports participation between June and August 2019. Data was evaluated using three common scoring methods: simple summation, mean, and transformed summation. Data was compared by Grades 1-5 and 6-8. RESULTS: The summary statistics of the scores show that there is no statistically significant difference across the scoring methods by population. A paired t-test evaluation of the different scoring methods shows that while the scores are very similar within methodology (simple summation, mean, transformed sum) they are all statistically significantly different from one another, which demonstrates that for any given individual the specific scoring methodology used can result in meaningful differences. The transformed sum provided the strongest methodologic result. Analysis also concluded that administering the scale by proxy to children from grades 1-5 resulted in similar responses to those in Grades 6-8 broadening the appropriate populations able to use this scale. CONCLUSION: The transformed sum is the preferred scoring method. TRIAL REGISTRATION: Not applicable.

Evaluating the Impact of Youth Early Sport Specialization on Injury: An Evolution in Measurement.

Objective: To track youth sports participation and injury occurrence accurately and longitudinally. Results: An online survey tool that captures sports participation, frequency, level of competition, and tracks injury occurrence has been developed. The survey allows for longitudinal tracking of sports participation to evaluate the change from recreational to highly specialized sports participation. To maximize the utility of this research tool we identified swimmer plots which allow for clear visualization of the data as the best method for graphical representation. Implication: Longitudinal measurement of sports participation to evaluate the impact of early sports specialization on injury is feasible with this tool and enhanced by the swimmer plots for visualization.

Cardiorespiratory Fitness in Youth: An Important Marker of Health: A Scientific Statement From the American Heart Association.

Cardiorespiratory fitness (CRF) refers to the capacity of the circulatory and respiratory systems to supply oxygen to skeletal muscle mitochondria for energy production needed during physical activity. CRF is an important marker of physical and mental health and academic achievement in youth. However, only 40% of US youth are currently believed to have healthy CRF. In this statement, we review the physiological principles that determine CRF, the tools that are available to assess CRF, the modifiable and nonmodifiable factors influencing CRF, the association of CRF with markers of health in otherwise healthy youth, and the temporal trends in CRF both in the United States and internationally. Development of a cost-effective CRF measurement process that could readily be incorporated into office visits and in field settings to screen all youth periodically could help identify those at increased risk.

Sedentary Behaviors in Today's Youth: Approaches to the Prevention and Management of Childhood Obesity: A Scientific Statement From the American Heart Association.

This scientific statement is about sedentary behavior and its relationship to obesity and other cardiometabolic outcomes in youth. A deleterious effect of sedentary behavior on cardiometabolic health is most notable for screen-based behaviors and adiposity; however, this relation is less apparent for other cardiometabolic outcomes or when sedentary time is measured with objective movement counters or position monitors. Increasing trends of screen time are concerning; the portability of screen-based devices and abundant access to unlimited programming and online content may be leading to new patterns of consumption that are exposing youth to multiple pathways harmful to cardiometabolic health. This American Heart Association scientific statement provides an updated perspective on sedentary behaviors specific to modern youth and their impact on cardiometabolic health and obesity. As we reflect on implications for practice, research, and policy, what emerges is the importance of understanding the context in which sedentary behaviors occur. There is also a need to capture the nature of sedentary behavior more accurately, both quantitatively and qualitatively, especially with respect to recreational screen-based devices. Further evidence is required to better inform public health interventions and to establish detailed quantitative guidelines on specific sedentary behaviors in youth. In the meantime, we suggest that televisions and other recreational screen-based devices be removed from bedrooms and absent during meal times. Daily device-free social interactions and outdoor play should be encouraged. In addition, parents/guardians should be supported to devise and enforce appropriate screen time regulations and to model healthy screen-based behaviors.

Association of Habitual Physical Activity With Cardiovascular Risk Factors and Target Organ Damage in Adolescents and Young Adults.

BACKGROUND: We aimed to (1) compare a subjective and objective measure of habitual physical activity (PA), (2) determine the association of PA and cardiovascular risk factors, and (3) test the hypothesis that PA is an independent determinant of target organ damage in youth. METHODS: Cross-sectional analysis of youth with and without type 2 diabetes [mean age = 22 (3.9) y]. PA was measured with International Physical Activity Questionnaire and Actical accelerometer. Target organ damage was assessed with echocardiography and peripheral arterial testing. Subjects were stratified into tertiles of total PA, and differences were tested by analysis of variance and χ2 tests. General linear models tested for independent associations. RESULTS: The correlation between International Physical Activity Questionnaire and accelerometry was weak (r = .23, P = .0003). Less active subjects had worse cardiovascular risk profiles and target organ damage, including stiffer arteries (P < .01). These outcome differences did not reach statistical significance when adjusted for covariates, such as lipid levels and glycemic control. CONCLUSION: Survey assessment of PA is complicated by inaccurate reporting. There is a strong association of habitual PA with cardiovascular risk factor clustering. PA may exert its beneficial effect on arterial stiffness in obese youth through improved glycemic control.

Changes in Functional Mobility and Musculoskeletal Pain After Bariatric Surgery in Teens With Severe Obesity: Teen-Longitudinal Assessment of Bariatric Surgery (LABS) Study.

IMPORTANCE: Severe obesity is associated with mobility limitations and higher incidence of multijoint musculoskeletal pain. It is unknown whether substantial weight loss improves these important outcomes in adolescents with severe obesity. OBJECTIVE: To examine the association of bariatric surgery with functional mobility and musculoskeletal pain in adolescents with severe obesity up to 2 years after surgery. DESIGN, SETTING, AND PARTICIPANTS: The Teen-Longitudinal Assessment of Bariatric Surgery Study is a prospective, multicenter, observational study, which enrolled 242 adolescents (≤19 years of age) who were undergoing bariatric surgery from March 2007 through February 2012 at 5 US adolescent bariatric surgery centers. This analysis was conducted in November 2015. INTERVENTIONS: Roux-en-Y gastric bypass (n = 161), sleeve gastrectomy (n = 67), or laparoscopic adjustable gastric band (n = 14). MAIN OUTCOMES AND MEASURES: Participants completed a 400-m walk test prior to bariatric surgery (n = 206) and at 6 months (n = 195), 12 months (n = 176), and 24 months (n = 149) after surgery. Time to completion, resting heart rate (HR), immediate posttest HR, and HR difference (resting HR minus posttest HR) were measured and musculoskeletal pain concerns, during and after the test, were documented. Data were adjusted for age, sex, race/ethnicity, baseline body mass index (calculated as weight in kilograms divided by height in meters squared), and surgical center (posttest HR and HR difference were further adjusted for changes in time to completion). RESULTS: Of the 206 adolescents with severe obesity included in the study, 156 were female (75.7%), the mean (SD) age was 17.1 (1.6) years, and the mean (SD) body mass index was 51.7 (8.5). Compared with baseline, significant improvements were observed at 6 months for the walk test time to completion (mean, 376 seconds; 95% CI, 365-388 to 347 seconds; 95% CI, 340-358; P < .01), resting HR (mean, 84 beats per minute [bpm]; 95% CI, 82-86 to 74 bpm; 95% CI, 72-76), posttest HR (mean, 128 bpm; 95% CI, 125-131 to 113 bpm; 95% CI, 110-116), and HR difference (mean, 40 bpm; 95% CI, 36-42 to 34 bpm; 95% CI, 31-37). These changes in time to completion, resting HR, and HR difference persisted at 12 months and 24 months. Posttest HR further improved from 6 months to 12 months (mean, 113 bpm; 95% CI, 110-116 to 108 bpm; 95% CI, 105-111). There were statistically significant reductions in musculoskeletal pain concerns at all points. CONCLUSIONS AND RELEVANCE: These data provide evidence that bariatric surgery in adolescents with severe obesity is associated with significant improvement in functional mobility and in the reduction of walking-related musculoskeletal pain up to 2 years after surgery.

Child Physical Activity Associations With Cardiovascular Risk Factors Differ by Race.

PURPOSE: The objective of this study was to characterize the relationship between objectively-measured physical activity (PA) and cardiovascular risk factors in 7-year-old children and test the hypothesis that it differs by race. METHODS: Cross-sectional study of 308 7-year-old children drawn from a major US metropolitan community. PA (moderate-to-vigorous, MVPA; light, LPA; and inactivity, IA) was measured by accelerometry (RT3). Cardiovascular risk factors included BMI, blood pressure, and serum lipids, glucose and insulin concentrations. General linear modeling was used to evaluate the independent associations between PA measures and cardiovascular risk factors and interactions by race. RESULTS: In black children, greater time spent in PA was independently associated with lower levels of triglycerides (MVPA and LPA, both p < .01), glucose (MVPA, p < .05), and insulin (MVPA, p < .01); these associations were not evident in white children. Across races, greater inactivity was independently associated with greater low-density lipoprotein cholesterol in overweight participants (p < .01) but not in normal weight participants. No PA measure was associated with BMI, systolic blood pressure, or high-density lipoprotein cholesterol. CONCLUSIONS: In this cohort of 7-year-old children, the relationship between PA and some cardiovascular risk factors differed by race. These findings may have implications for targeting of PA promotion efforts in children.

Sixty minutes of what? A developing brain perspective for activating children with an integrative exercise approach.

Current recommendations for physical activity in children overlook the critical importance of motor skill acquisition early in life. Instead, they focus on the quantitative aspects of physical activity (eg, accumulate 60 min of daily moderate to vigorous physical activity) and selected health-related components of physical fitness (eg, aerobic fitness, muscular strength, muscular endurance, flexibility and body composition). This focus on exercise quantity in youth may limit considerations of qualitative aspects of programme design which include (1) skill development, (2) socialisation and (3) enjoyment of exercise. The timing of brain development and associated neuroplasticity for motor skill learning makes the preadolescence period a critical time to develop and reinforce fundamental movement skills in boys and girls. Children who do not participate regularly in structured motor skill-enriched activities during physical education classes or diverse youth sports programmes may never reach their genetic potential for motor skill control which underlies sustainable physical fitness later in life. The goals of this review are twofold: (1) challenge current dogma that is currently focused on the quantitative rather than qualitative aspects of physical activity recommendations for youth and (2) synthesise the latest evidence regarding the brain and motor control that will provide the foundation for integrative exercise programming that provide a framework sustainable activity for life.

Outdoor Temperature, Precipitation, and Wind Speed Affect Physical Activity Levels in Children: A Longitudinal Cohort Study.

OBJECTIVE: Evaluate effects of local weather conditions on physical activity in early childhood. METHODS: Longitudinal prospective cohort study of 372 children, 3 years old at enrollment, drawn from a major US metropolitan community. Accelerometer-measured (RT3) physical activity was collected every 4 months over 5 years and matched with daily weather measures: day length, heating/cooling degrees (degrees mean temperature < 65°F or ≥ 65°F, respectively), wind, and precipitation. Mixed regression analyses, adjusted for repeated measures, were used to test the relationship between weather and physical activity. RESULTS: Precipitation and wind speed were negatively associated with total physical activity and moderate-vigorous physical activity (P < .0001). Heating and cooling degrees were negatively associated with total physical activity and moderate-vigorous physical activity and positively associated with inactivity (all P < .0001), independent of age, sex, race, BMI, day length, wind, and precipitation. For every 10 additional heating degrees there was a 5-minute daily reduction in moderate-vigorous physical activity. For every additional 10 cooling degrees there was a 17-minute reduction in moderate-to-vigorous physical activity. CONCLUSIONS: Inclement weather (higher/lower temperature, greater wind speed, more rain/snow) is associated with less physical activity in young children. These deleterious effects should be considered when planning physical activity research, interventions, and policies.

Usefulness of combined history, physical examination, electrocardiogram, and limited echocardiogram in screening adolescent athletes for risk for sudden cardiac death.

Sudden cardiac death in the young (SCDY) is the leading cause of death in young athletes during sport. Screening young athletes for high-risk cardiac defects is controversial. The purpose of this study was to assess the utility and feasibility of a comprehensive cardiac screening protocol in an adolescent population. Adolescent athletes were recruited from local schools and/or sports teams. Each subject underwent a history and/or physical examination, an electrocardiography (ECG), and a limited echocardiography (ECHO). The primary outcome measure was identification of cardiac abnormalities associated with an elevated risk for sudden death. We secondarily identified cardiac abnormalities not typically associated with a short-term risk of sudden death. A total of 659 adolescent athletes were evaluated; 64% men. Five subjects had cardiac findings associated with an elevated risk for sudden death: prolonged QTc >500 ms (n = 2) and type I Brugada pattern (n = 1), identified with ECG; dilated cardiomyopathy (n = 1) and significant aortic root dilation; and z-score = +5.5 (n = 1). History and physical examination alone identified 76 (11.5%) subjects with any cardiac findings. ECG identified 76 (11.5%) subjects in which a follow-up ECHO or cardiology visit was recommended. Left ventricular mass was normal by ECHO in all but 1 patient with LVH on ECG. ECHO identified 34 (5.1%) subjects in whom a follow-up ECHO or cardiology visit was recommended. In conclusion, physical examination alone was ineffective in identification of subjects at elevated risk for SCDY. Screening ECHO identified patients with underlying cardiac disease not associated with immediate risk for SCDY. Cost of comprehensive cardiac screening is high.

Assessment of active play, inactivity and perceived barriers in an inner city neighborhood.

Avondale, a disadvantaged neighborhood in Cincinnati, lags behind on a number of indicators of child well-being. Childhood obesity has become increasingly prevalent, as one-third of Avondale's kindergarteners are obese or overweight. The study objective was to determine perceptions of the quantity of and obstacles to childhood physical activity in the Avondale community. Caregivers of children from two elementary schools were surveyed to assess their child's physical activity and barriers to being active. Three hundred and forty surveys were returned out of 1,047 for a response rate of 32%. On school days, 41% of caregivers reported that their children spent more than 2 h watching television, playing video games, or spending time on the computer. While over half of respondents reported that their children get more than 2 h of physical activity on school days, 14% of children were reported to be physically active less than 1 h per day. Caregivers identified violence, cost of extracurricular activities, and lack of organized activities as barriers to their child's physical activity. The overwhelming majority of caregivers expressed interest in a program to make local playgrounds safer. In conclusion, children in Avondale are not participating in enough physical activity and are exposed to more screen time than is recommended by the AAP. Safety concerns were identified as a critical barrier to address in future advocacy efforts in this community. This project represents an important step toward increasing the physical activity of children in Avondale and engaging the local community.

Tracking of accelerometer-measured physical activity in early childhood.

Establishing and maintaining healthy physical activity (PA) levels is important throughout life. The purpose of this study was to determine the extent of PA tracking between ages 3 and 7 y. Objective measures of PA (RT3, triaxial accelerometer) were collected every 4 mo from ages 3-7; data from 234 children with PA measures available during each year of age were analyzed. Mean PA (total, moderate/vigorous (MV), and inactivity [IA]) was calculated for each year of age and adjusted for wear time. Correlations with age 3 PA were moderate at age 4 (r = .42-.45) but declined by age 7 (r = .19-.25). After classification into sex-specific tertiles of PA at age 3, boys in the high age 3 MVPA tertile maintained significantly higher PA at all subsequent ages, while girls in the high age 3 MVPA tertile were not significantly higher at age 6 and 7. Boys and girls in the high age 3 IA tertile had significantly higher IA at multiple subsequent years of age (p < .05 at ages 5 and 6). In conclusion, boys who were relatively more active at age 3 remained more active for several subsequent years. These findings highlight early-childhood differences in physical activity patterns between boys and girls.

Is body composition associated with an increased risk of developing anterior knee pain in adolescent female athletes?

OBJECTIVE: To determine the relationship between relative body composition and body mass to height, anterior knee pain, or patellofemoral pain (PFP) in adolescent female athletes. BACKGROUND: Patellofemoral pain is common in female athletes and has an undefined etiology. The purpose of this study was to examine whether there was an association among higher body mass index (BMI), BMI z-scores, and relative body fat percentage in the development of PFP in an adolescent female athlete population. We hypothesized that female athletes who developed PFP over the course of a competitive basketball season had higher relative body mass or body fat percentage compared with those who did not develop PFP. METHODS: Fifteen middle school basketball teams that consisted of 248 basketball players (mean age, 12.76 ± 1.13 years; height, 158.43 ± 7.78 cm; body mass, 52.35 ± 12.31 kg; BMI, 20.73 ± 3.88 kg/m(2)) agreed to participate in this study over the course of 2 basketball seasons, resulting in 262 athlete-seasons. Testing included the completion of the Anterior Knee Pain Scale (AKPS), International Knee Documentation Committee (IKDC) form, standardized history, physician-administered physical examination, maturational estimates, and anthropometrics. RESULTS: Of the 262 athlete-seasons monitored, 39 athletes developed PFP over the course of the study. The incidence rate of new PFP was 1.57 per 1000 athlete-exposures. The cumulative incidence of PFP was 14.9%. There was no difference in BMI between those who developed PFP (mean body mass, 20.2 kg/m(2); 95% CI,18.9-21.4) and those who did not develop PFP (mean body mass, 20.8 kg/m(2); 95% CI, 20.3-21.3;P > 0.05). Body mass index z-scores were not different between those who developed PFP (mean, 0.3; 95% CI, 0.7-0.6) and those who did not develop PFP (mean, 0.4; 95% CI, 0.3-0.6;P > 0.05). A similar trend was noted in relative body fat percentage, with mean scores of similar ranges in those who developed PFP (mean body fat percentage, 22.2%; 95% CI, 19.4-24.9) to the referent group who did not (mean body fat percentage, 22.9%; 95% CI, 21.8-24.1;P > 0.05). CONCLUSIONS: Our results do not indicate a relationship between relative body composition or relative body mass to height to the propensity to develop PFP in middle school-aged female basketball players. Although previous data indicate a relationship between higher relative body mass and overall knee injury, these data did not support this association with PFP specifically. These data suggest the underlying etiology of PFP may be neuromuscular in nature. Further research is needed to understand the predictors, etiology, and ultimate prevention of this condition.

Physical activity is independently associated with multiple measures of arterial stiffness in adolescents and young adults.

Physical activity (PA) is associated with decreased levels of arterial stiffness in adults, but the relationship between PA and multiple measures of arterial stiffness in adolescents and young adults is not clear. The objective of this study was to test the hypothesis that PA is an independent predictor of multiple measures of arterial stiffness in adolescents and young adults. A total of 548 participants were enrolled in a study of the cardiovascular effects of obesity and type 2 diabetes mellitus (T2DM) (lean, 201; obese, 191; T2DM, 156). Anthropometrics, blood pressure, central and peripheral measures of arterial stiffness (pulse wave velocity, brachial distensibility, and augmentation index), blood (lipids and metabolic tests), and accelerometry data were collected. General linear modeling was performed to test for the independent relationship of PA on arterial stiffness. The mean age of the participants was 17.9 years (standard deviation, 3.5 years). After adjusting for other cardiovascular disease risk factors such as age, sex, body size, mean arterial pressure, and the presence of obesity or T2DM, PA was an independent predictor of augmentation index and brachial distensibility (P < .001). A greater effect of PA on pulse wave velocity was found in participants with T2DM (P = .009) compared with participants in the lean or obese groups. Physical activity is significantly and independently associated with multiple measures of arterial stiffness in adolescents and young adults. The role of PA in the prevention of cardiovascular disease target organ damage in youth, independent of energy balance, merits further exploration.

Attitudes of Wisconsin pediatricians toward influenza immunization.

OBJECTIVE: Determine the influenza immunization practices of Wisconsin pediatricians in response to evolving influenza prevention strategy in the United States. DESIGN: Two hundred fifty members of the Wisconsin Chapter of the American Academy of Pediatrics were surveyed prior to the 2004-2005 influenza season about their expectations for implementing the latest and future influenza vaccination recommendations for children and their use of trivalent inactivated influenza vaccines free of thimerosal as a preservative. RESULTS: Ninety-two percent of respondents expected to vaccinate most medically high-risk children against influenza, but only 53% would recommend influenza vaccine for most of their household contacts. Although 57% planned to vaccinate most healthy children ages 6 months to 23 months, just 27% thought the majority of household contacts of healthy infants under 23 months of age would be vaccinated. Fewer than 24% favored universal influenza vaccination for the majority of healthy school-aged children. Seventy percent had little or no concern about recommending thimerosal-containing influenza vaccines, but 60% agreed or strongly agreed thimerosal-free vaccine availability would increase parental acceptance of vaccinating their children. CONCLUSION: Although Wisconsin pediatricians are aware of the importance of preventing influenza disease in children, barriers to universal influenza vaccination of children and key household contacts remain.