Attention bias variability and posttraumatic stress symptoms: the mediating role of emotion regulation difficulties.

Growing literature has linked attention bias variability (ABV) to the experience and treatment of posttraumatic stress disorder (PTSD). Unlike assessments of attention bias in only one direction, ABV captures dynamic fluctuations in attention toward and away from threat. While mechanisms underlying the ABV-PTSD relations are unclear, some research implicates emotion regulation difficulties. The current study examined in community women with varying PTSD symptom severity, the amount of variance in the association between ABV and PTSD accounted for by emotion regulation difficulties. The full sample (N = 74) was comprised of 59% community women with PTSD due to domestic and/or sexual violence, and 41% community women without PTSD. All participants completed self-report questionnaires including the Difficulties in Emotion Regulation Scale-16, which assessed emotion regulation. ABV was calculated following a computerised dot probe task. The indirect effect of ABV on PTSD symptom severity through emotion regulation difficulties was statistically significant, while the direct effect between ABV and PTSD symptom severity was not significant. Findings replicated after controlling for total trauma exposure. Clinical implications and literature suggesting how ABV may perpetuate emotion regulation difficulties associated with PTSD symptomology are discussed.

Association of Maternal Gestational Weight Gain With the Infant Fecal Microbiota.

OBJECTIVES: Pregnancy characteristics may influence the infant fecal microbiota during early life. We aimed to examine associations of maternal gestational weight gain with infant fecal microbiota composition, bacterial community richness, and Shannon diversity index. METHODS: We analyzed data from a prospective cohort study of healthy infants. We collected prenatal data, including report of mother's gestational weight gain, and infant fecal samples from 84 infant-mother dyads. By applying 16S rRNA gene sequencing and an unbiased clustering by partitioning around medoids using Bray-Curtis distances, we identified 4 fecal microbiota profiles, and examined the associations of maternal gestational weight gain with the 4 fecal microbiota profiles, bacterial community richness, and Shannon diversity index. RESULTS: Overall, the median age of infants was 4.0 months and 43% were girls. The mothers of the 84 infants gained a mean of 14.2 kg (standard deviation, 5.4 kg) during pregnancy. We identified 4 distinct microbiota profiles: Bifidobacterium-dominant (42%), Enterobacter/Veillonella-dominant (23%), Bacteroides-dominant (19%), and Escherichia-dominant (17%). Infants whose mothers had higher gestational weight gain were less likely to have a Bacteroides-dominant profile, corresponding to a relative risk ratio of 0.83 (95% confidence interval, 0.71-0.96; P = 0.01) per 1 kg increase in weight. In addition, higher gestational weight gain was also associated with lower bacterial community richness and Shannon diversity index (P < 0.05). CONCLUSIONS: In this prospective cohort study of healthy infants, maternal gestational weight gain was associated with the infant fecal microbiota profiles, bacterial community richness, and Shannon diversity index.

Spatial analysis of crime incidence and adolescent physical activity.

OBJECTIVES: Adolescents do not achieve recommended levels of physical activity. Crime is believed to be a barrier to physical activity among youth, but findings are inconsistent. This study compares the spatial distribution of crime incidences and moderate-to-vigorous physical activity (MVPA) among adolescents in Massachusetts between 2011 and 2012, and examines the correlation between crime and MVPA. METHODS: Eighty adolescents provided objective physical activity (accelerometer) and location (Global Positioning Systems) data. Crime report data were obtained from the city police department. Data were mapped using geographic information systems, and crime and MVPA densities were calculated using kernel density estimations. Spearman's correlation tested for associations between crime and MVPA. RESULTS: Overall, 1694 reported crimes and 16,702min of MVPA were included in analyses. A strong positive correlation was present between crime and adolescent MVPA (ρ=0.72, p<0.0001). Crime remained positively associated with MVPA in locations falling within the lowest quartile (ρ=0.43, p<0.0001) and highest quartile (ρ=0.32, p<0.0001) of crime density. CONCLUSIONS: This study found a strong positive association between crime and adolescent MVPA, despite research suggesting the opposite relationship. This counterintuitive finding may be explained by the logic of a common destination: neighborhood spaces which are desirable destinations and promote physical activity may likewise attract crime.

Adolescents' use of the built environment for physical activity.

BACKGROUND: Physical activity is a health-enhancing behavior, but few adolescents achieve the recommended levels of moderate-to-vigorous physical activity. Understanding how adolescents use different built environment spaces for physical activity and activity varies by location could help in designing effective interventions to promote moderate-to-vigorous physical activity. The objective of this study was to describe the locations where adolescents engage in physical activity and compare traditional intensity-based measures with continuous activity when describing built environment use patterns among adolescents. METHODS: Eighty adolescents aged 11-14 years recruited from community health and recreation centers. Adolescents wore accelerometers (Actigraph GT3X) and global positioning system receivers (QStarz BT-Q1000XT) for two separate weeks to record their physical activity levels and locations. Accelerometer data provided a continuous measure of physical activity and intensity-based measures (sedentary time, moderate-to-vigorous physical activity). Physical activity was mapped by land-use classification (home, school, park, playground, streets & sidewalks, other) using geographic information systems and this location-based activity was assessed for both continuous and intensity-based physical activity derived from mixed-effects models which accounted for repeated measures and clustering effects within person, date, school, and town. RESULTS: Mean daily moderate-to-vigorous physical activity was 22 minutes, mean sedentary time was 134 minutes. Moderate-to-vigorous physical activity occurred in bouts lasting up to 15 minutes. Compared to being at home, being at school, on the streets and sidewalks, in parks, and playgrounds were all associated with greater odds of being in moderate-to-vigorous physical activity and achieving higher overall activity levels. Playground use was associated with the highest physical activity level (ß = 172 activity counts per minute, SE = 4, p < 0.0001) and greatest odds of being in moderate-to-vigorous physical activity (odds ratio 8.3, 95% confidence interval 4.8-14.2). CONCLUSION: Adolescents were more likely to engage in physical activity, and achieved their highest physical activity levels, when using built environments located outdoors. Novel objective methods for determining physical activity can provide insight into adolescents' spatial physical activity patterns, which could help guide physical activity interventions. Promoting zoning and health policies that encourage the design and regular use of outdoor spaces may offer another promising opportunity for increasing adolescent physical activity.

Comparing self-identified and census-defined neighborhoods among adolescents using GPS and accelerometer.

BACKGROUND: Numerous definitions of neighborhood exist, yet few studies have considered youth's perceptions of neighborhood boundaries. This study compared youth-identified neighborhood (YIN) boundaries to census-defined neighborhood (CDN) boundaries, and determined how the amount of time spent and moderate-to-vigorous physical activity (MVPA) levels compared within both boundary types. METHODS: Adolescents aged 11-14 years were asked to identify their neighborhood boundaries using a map. Objective location and physical activity data collected using Global Positioning System (GPS) devices and accelerometers were used to calculate the amount of time spent and MVPA within youth-identified and census-defined neighborhood boundaries. Paired bivariate analyses compared mean area (meters squared), percent of total time, daily MVPA (minutes), time density (minutes/m2) and MVPA density (minutes/m2) for both boundary types. RESULTS: Youth-identified neighborhoods (1,821,705 m²) and census-defined neighborhoods (1,277,181 m²) were not significantly different in area, p = 0.30. However, subjects spent more time in youth-identified neighborhoods (80.3%) than census-defined neighborhoods (58.4%), p < 0.0001, and engaged in more daily MVPA within youth-identified neighborhoods (14.7 minutes) than census-defined neighborhoods (9.5 minutes), p < 0.0001. After adjusting for boundary area, MVPA density (minutes of MVPA per squared meter of area) remained significantly greater for youth-identified neighborhoods (2.4 × 10-4 minutes/m²) than census-defined neighborhoods (1.4 × 10-4 minutes/m²), p = 0.02. CONCLUSIONS: Adolescents perceive their neighborhoods to be similar in size to census-defined neighborhoods. However, youth-identified neighborhoods better capture the locations in which adolescents spend time and engage in physical activity. Asking adolescents to identify their neighborhood boundaries is a feasible and valuable method for identifying the spaces that adolescents are exposed to and use to be physically active.

Identification of chemosensory receptor genes in Manduca sexta and knockdown by RNA interference.

BACKGROUND: Insects detect environmental chemicals via a large and rapidly evolving family of chemosensory receptor proteins. Although our understanding of the molecular genetic basis for Drosophila chemoreception has increased enormously in the last decade, similar understanding in other insects remains limited. The tobacco hornworm, Manduca sexta, has long been an important model for insect chemosensation, particularly from ecological, behavioral, and physiological standpoints. It is also a major agricultural pest on solanaceous crops. However, little sequence information and lack of genetic tools has prevented molecular genetic analysis in this species. The ability to connect molecular genetic mechanisms, including potential lineage-specific changes in chemosensory genes, to ecologically relevant behaviors and specializations in M. sexta would be greatly beneficial. RESULTS: Here, we sequenced transcriptomes from adult and larval chemosensory tissues and identified chemosensory genes based on sequence homology. We also used dsRNA feeding as a method to induce RNA interference in larval chemosensory tissues. CONCLUSIONS: We report identification of new chemosensory receptor genes including 17 novel odorant receptors and one novel gustatory receptor. Further, we demonstrate that systemic RNA interference can be used in larval olfactory neurons to reduce expression of chemosensory receptor transcripts. Together, our results further the development of M. sexta as a model for functional analysis of insect chemosensation.

A Multimodal Counseling-Based Adolescent Physical Activity Intervention.

PURPOSE: National guidelines recommend adolescents achieve 60 minutes of moderate-to-vigorous physical activity (MVPA)/day, yet few adolescents meet these guidelines. METHODS: We piloted a novel quasi-randomized physical activity intervention to promote adolescent's use of their surrounding built environment among 30 intervention and 30 control overweight/obese adolescents aged 10-16 years living in greater Boston from 2013 to 2015. Location-specific MPVA was measured by accelerometry and global positioning system for three one-week periods (Time 1 [T1], Time 2 [T2], and Time 3 [T3]). One month after T1, intervention participants received individualized counseling on how to use their surrounding built environment to increase MVPA, and control participants received standard-of-care lifestyle modification counseling; both groups received their T1 physical activity data. T2 assessment occurred the week after the counseling visit and T3 assessment 3-4 months later. The main outcome was change in average daily minutes of MVPA; the secondary outcome was meeting national MVPA guidelines. Multivariable modeling accounted for covariates (baseline MVPA, body mass index, age, sex, race/ethnicity) and clustering by study group and town. RESULTS: Among the 60 adolescents recruited, 55 (92%) completed data collection. Short-term (T2) intervention effects included increased average MVPA of +13.9 minutes intervention versus -.6 minutes control (p < .0001). Differential increase in mean daily MVPA was sustained at T3 (9.3 minutes more in intervention group; p = .0006). The proportion of adolescents in the intervention group who achieved 60 minutes/day of MVPA increased from 11% (T1) to 21% (T2), whereas declining (7%-0%) among controls. CONCLUSIONS: Individualized counseling about the built environment can help increase MVPA among overweight and obese adolescents.

Design and implementation of a physical activity intervention to enhance children's use of the built environment (the CUBE study).

BACKGROUND: Adequate physical activity promotes physical and mental health and decreases obesity risk. However, most adolescents do not attain recommended physical activity levels and effective interventions are lacking. Physical activity trials rarely incorporate built environment use patterns. PURPOSE: This paper describes the design and rationale of the Children's Use of the Built Environment (CUBE) Study, an office-based intervention designed to teach youth how to use their surrounding built environment to increase physical activity. METHODS: CUBE is a 6-month intervention trial among 60 overweight and obese 10-16 year old adolescents from a community health center in Massachusetts. The study began in the winter of 2013. Patients are sequentially assigned to either the intervention or control group. Baseline physical activity by accelerometry and location by GPS, along with measured height, weight, and blood pressure are collected. Control subjects receive standard of care lifestyle counseling. Intervention subjects receive tailored recommendations on how to increase their physical activity based on their accelerometer and GPS data. Data collections are repeated at end-of-treatment, and again 3 months later. CONCLUSION: The findings from this study should help guide future efforts to design interventions aimed at increasing adolescent physical activity as well as to inform design professionals and government officials charged with creating outdoor spaces where adolescents spend time.

Design and clinical feasibility of personal wearable monitor for measurement of activity and environmental exposure.

Human exposure to specific environmental factors (e.g. air quality, lighting, and sound) is known to play an important role in the pathogenesis of many chronic diseases (e.g. asthma) and mental health disorders (e.g. anxiety). However, conventional fixed environmental monitoring stations are sparsely located and, despite environmental models, cannot adequately assess individual exposure levels. New forms of low-cost portable monitors have begun to emerge that enable the collection of higher spatial density "crowd sourced" data; however, the first generation of these low-cost environmental monitors have generally not been suitable for clinical environmental health studies due to practical challenges such as calibration, reproducibility, form factor, and battery life. In this paper, we present a wearable environmental monitor that overcomes these challenges and can be used in clinical studies The new device, called "Eco-Mini," can be used without a smart phone and is capable of locally sampling and recording a variety of environmental parameters (Ozone, Sulfur Dioxide, Volatile Organic Compounds, humidity, temperature, ambient light color balance, and sound level) as well as individual activity (3-axis accelerometer) and location (GPS). In this paper, we also report findings and discuss lessons learned from a feasibility study conducted for one week with pediatric patients as part of an ongoing asthma research study.

Adolescent report of lifestyle counseling.

BACKGROUND: Physician counseling on lifestyle factors has been recommended as one way to help combat the obesity epidemic in the United States. The aim of this study was to examine the frequency of lifestyle counseling among healthy weight, overweight, and obese adolescents and determine the contributions of adolescent weight and physical activity. METHODS: Self-reported surveys on dietary and physical activity counseling, along with measured height, weight, and physical activity data by accelerometry were collected on 76 adolescents ages 11-14 years. General linear models tested for associations of reported lifestyle counseling by weight category, adjusting for physical activity, age, gender, race/ethnicity, and parent education. RESULTS: Half (47%) of the subjects were overweight or obese. Frequency of lifestyle counseling varied by weight category, with obese adolescents reporting greater amounts of lifestyle counseling across all topics than their peers. Obese adolescents received more dietary (ß = 0.88; standard error [SE] = 0.25; p = 0.001) and physical activity (ß = 0.80; SE = 0.28; p = 0.006) counseling than healthy weight youth, as well as being told to increase their physical activity more often (ß = 0.96; SE = 0.29; p = 0.001). There were no differences in lifestyle counseling between overweight and healthy weight subjects. Adolescents with greater daily moderate-to-vigorous physical activity reported less physical activity counseling (ß = -0.02; SE = 0.008; p = 0.05). CONCLUSIONS: Despite universal recommendations to counsel adolescents on lifestyle, only obese adolescents consistently report receiving such counseling. Given known difficulties in reversing obesity after onset, efforts should ensure that all adolescents receive lifestyle counseling.

The influence of the built environment on outcomes from a "walking school bus study": a cross-sectional analysis using geographical information systems.

Active commuting to school increases children's daily physical activity. The built environment is associated with children's physical activity levels in cross-sectional studies. This study examined the role of the built environment on the outcomes of a "walking school bus" study. Geographical information systems was used to map out and compare the built environments around schools participating in a pilot walking school bus randomised controlled trial, as well as along school routes. Multi-level modelling was used to determine the built environment attributes associated with the outcomes of active commuting to school and accelerometer-determined moderate-to-vigorous physical activity (MPVA). There were no differences in the surrounding built environments of control (n = 4) and intervention (n = 4) schools participating in the walking school bus study. Among school walking routes, park space was inversely associated with active commuting to school (ß = -0.008, SE = 0.004, P = 0.03), while mixed-land use was positively associated with daily MPVA (ß = 60.0, SE = 24.3, P = 0.02). There was effect modification such that high traffic volume and high street connectivity were associated with greater moderate-to-vigorous physical activity. The results of this study suggest that the built environment may play a role in active school commuting outcomes and daily physical activity.