Novel patterns of physical activity in a large sample of preschool-aged children.

BACKGROUND: Moderate-to-vigorous physical activity (MVPA), shown to be associated with health benefits, is not well-characterized in preschool-aged children. MVPA is commonly described as a threshold amount to achieve. We examined a novel way to characterize MVPA patterns in preschool-aged children by gender and age. METHODS: Preschool-aged children from Nashville, TN and Minneapolis, MN wore triaxial accelerometers. Four distinct MVPA patterns were identified: isolated spurt (IS), isolated sustained activity (ISA), clustered spurt (CS), and clustered sustained activity (CSA). Multivariable linear regression models were used to test associations of gender and age with each pattern. RESULTS: One thousand one hundred thirty-one children (3.9 years old, 51% girls, 30% overweight, 11% obese, and 76% Hispanic) wore accelerometers for 12.9 (SD = 1.4) hours/day for 6.7 (SD = 0.7) days. Children spent 53% of wear time in sedentary behavior and 13% in MVPA. On average, boys and girls achieved > 90 min/day of MVPA (98.2 min, SD = 32.3). Most MVPA (80%) was obtained in spurt-like (IS and CS) MVPA; however, girls spent a higher proportion of MVPA in IS and CS, and lower proportion of time in CSA (all p < 0.001). Controlling for gender, an increase of 1-year in age corresponded to a 1.5% increase in CSA (p < 0.05). CONCLUSIONS: How MVPA was obtained varied depending on the gender and age of the child. On average, boys spent more time in sustained MVPA than girls and MVPA was more sustained in older children. Utilizing these patterns could inform PA practice and policy guidelines. TRIAL REGISTRATION: NCT01316653 , date of registration: March 3, 2011; NCT01606891, date of registration: May 23, 2012.

A QUANTITATIVE PCR ASSAY FOR A MYCOPLASMA FROM EMYDID TURTLES INDICATES HIGH PREVALENCE IN HEALTHY THREE-TOED BOX TURTLES (TERRAPENE CAROLINA TRIUNGUIS) FROM MISSOURI, USA.

We evaluated cause of injury and quantified levels of three potential mycoplasmal pathogens (Mycoplasma agassizii, Mycoplasma testudineum, and an emydid mycoplasma) in three-toed box turtles (Terrapene carolina triunguis) from the greater St. Louis, Missouri, US area, brought to and housed at the Wildlife Rescue Center (Ballwin, Missouri, US) in 2015 and 2016. We created a probebased quantitative PCR (qPCR) assay for the emydid mycoplasma, with a similar specificity and sensitivity as the existing qPCR assays for M. agassizii and M. testudineum. All three microbes have been implicated in the development of upper respiratory tract disease in turtles and tortoises. We assessed whether signs of respiratory disease, sex, type of trauma, or treatment (administration of antibiotics) affected the presence of pathogens. We found that the most common types of injury experienced by turtles (n=85) were due to motor vehicles and other types of machinery, and that injuries due to motor vehicles were the most severe. We found a 61% prevalence of emydid mycoplasma (n=28) but M. agassizii or M. testudineum were not detected. Prevalence of disease and antibiotic treatment was too low to statistically relate to levels of mycoplasma. Sex and type of trauma were not associated with levels of emydid mycoplasma. The box turtle population we sampled did not experience signs of respiratory disease due to the fairly widespread prevalence of emydid mycoplasma. However, mycoplasmal diseases can be pathogen load-dependent. The qPCR we designed can be used to assess levels of emydid mycoplasma in other emydid species, populations, and individuals, in which there might be a positive association between the microbe and expression of respiratory disease.

Expression of an engrailed-LMO4 fusion protein in mammary epithelial cells inhibits mammary gland development in mice.

LIM domain factors and associated cofactors are important developmental regulators in pattern formation and organogenesis. In addition, overexpression of two LIM-only factors (LMOs) causes acute lymphocytic leukemia. The more recently discovered LMO factor LMO4 is highly expressed in proliferating epithelial cells, and frequently overexpressed in breast carcinoma. Here we show that while LMO4 is expressed throughout mammary gland development, it is dramatically upregulated in mammary epithelial cells during midpregnancy. The LMO coactivator Clim2/Ldb1/NLI showed a similar expression pattern, consistent with the idea that LMO4 and Clim2 act as a complex in mammary epithelial cells. In MCF-7 cells, LMO4 transcripts were upregulated by heregulin, an activator of ErbB receptors that are known to be important in mammary gland development and breast cancer. To test the hypothesis that LMO4 plays roles in mammary gland development, we created an engrailed-LMO4 fusion protein. This fusion protein maintains the ability to interact with Clim2, but acts as a dominant repressor of both basal and activated transcription when recruited to a DNA-regulatory region. When the engrailed-LMO4 fusion protein was expressed under control of the MMTV promoter in transgenic mice, both ductular development in virgin mice and alveolar development in pregnant mice were inhibited. These results suggest that LMO4 plays a role in promoting mammary gland development.

A novel approach to characterize physical activity patterns in preschool-aged children.

OBJECTIVE: Routine moderate-to-vigorous physical activity (MVPA) is associated with better health outcomes; the purpose of this work was to evaluate healthy preschooler physical activity patterns with objective measurement. METHODS AND PROCEDURES: An objective prospective study of 50 normally developing children 3-5 years old who were ≥50th and <95th BMI percentile and enrolled in a family-based healthy lifestyle study in 2011-2012. Participants wore a tri-axial accelerometer for 7 continuous days. Outcome measures consisted of wear time examining four common MVPA patterns: isolated spurt (IS), isolated sustained activity (ISA), clustered spurt (CS), and clustered sustained activity (CSA). RESULTS: Participants were 4.3 years, 56% female, 52% African-American, and 26% overweight. Forty-five children met wear time criteria. On average, children spent 14.5% of wake-wear time in MVPA, requiring 11.3 h to complete 90% of their daily MVPA. Children spent the majority of MVPA in CS (62.1%, followed by CSA (20.1%). Remaining MVPA was spent in IS (15.5%) and ISA (2.3%). CONCLUSION: It takes most of the waking day for preschoolers to attain their PA. They engage in short spurts of small duration, in four common MVPA patterns. Utilizing this method could better characterize preschooler physical activity needs in practice and policy guidelines.

The relationship between hispanic parents and their preschool-aged children's physical activity.

OBJECTIVE: The goal of this study was to examine activity pattern associations between Hispanic parents and their preschool-aged children. METHODS: We examined baseline data collected as part of a randomized controlled trial. Self-defined Hispanic parents with children aged 3 to 5 years were randomly assigned to either a weekly healthy lifestyle group (intervention) or a monthly school-readiness group (control) for 3 months. There were no weight eligibility criteria. All participants were instructed to wear an accelerometer for up to 7 consecutive days to measure physical activity. RESULTS: Of the 106 dyads enrolled in the study, 80 children and 85 parents provided useable actigraphy data. Mean percentage of time spent in sedentary behaviors was 82.0% (SD: 10.4) for parents and 69.8% (SD: 18.5) for preschool-aged children. Percentage of awake time per day spent in sedentary behavior was strongly correlated for parents and children (r = 0.597; P < .001). Correlations between activity level were large (r = 0.895 and 0.739 for low and moderate activity levels, respectively), except for vigorous activity level, for which the parent-child correlation was nonsignificant (P = .64) because of a near-0 level of vigorous parental activity. Child's age (P = .81) and gender (P = .43) were nonsignificant predictors of child activity levels. CONCLUSIONS: These results suggest that parental activity levels are a powerful explanation of preschool-aged child activity levels, except for vigorous activity, which children do on their own without parental participation. Hispanic parents play a critical role in setting physical activity patterns in their children.