Associations of sedentary behaviour, physical activity, blood pressure and anthropometric measures with cardiorespiratory fitness in children with cerebral palsy

Background - Children with cerebral palsy (CP) have poor cardiorespiratory fitness in comparison to their peers with typical development, which may be due to low levels of physical activity. Poor cardiorespiratory fitness may contribute to increased cardiometabolic risk. Purpose - The aim of this study was to determine the association between sedentary behaviour, physical activity and cardiorespiratory fitness in children with CP. An objective was to determine the association between cardiorespiratory fitness, anthropometric measures and blood pressure in children with CP. Methods- This study included 55 ambulatory children with CP [mean (SD) age 11.3 (0.2) yr, range 6-17 yr; Gross Motor Function Classification System (GMFCS) levels I and II]. Anthropometric measures (BMI, waist circumference and waist-height ratio) and blood pressure were taken. Cardiorespiratory fitness was measured using a 10 m shuttle run test. Children were classified as low, middle and high fitness according to level achieved on the test using reference curves. Physical activity was measured by accelerometry over 7 days. In addition to total activity, time in sedentary behaviour and light, moderate, vigorous, and sustained moderate-to-vigorous activity (≥10 min bouts) were calculated. Results - Multiple regression analyses revealed that vigorous activity (β = 0.339, p<0.01), sustained moderate-to-vigorous activity (β = 0.250, p<0.05) and total activity (β = 0.238, p<0.05) were associated with level achieved on the shuttle run test after adjustment for age, sex and GMFCS level. Children with high fitness spent more time in vigorous activity than children with middle fitness (p<0.05). Shuttle run test level was negatively associated with BMI (r2 = -0.451, p<0.01), waist circumference (r2 = -0.560, p<0.001), waist-height ratio (r2 = -0.560, p<0.001) and systolic blood pressure (r2 = -0.306, p<0.05) after adjustment for age, sex and GMFCS level. Conclusions - Participation in physical activity, particularly at a vigorous intensity, is associated with high cardiorespiratory fitness in children with CP. Low cardiorespiratory fitness is associated with increased cardiometabolic risk

Paleogene Radiation of a Plant Pathogenic Mushroom

Background: The global movement and speciation of fungal plant pathogens is important, especially because of the economic losses they cause and the ease with which they are able to spread across large areas. Understanding the biogeography and origin of these plant pathogens can provide insights regarding their dispersal and current day distribution. We tested the hypothesis of a Gondwanan origin of the plant pathogenic mushroom genus Armillaria and the currently accepted premise that vicariance accounts for the extant distribution of the species. Methods: The phylogeny of a selection of Armillaria species was reconstructed based on Maximum Parsimony (MP), Maximum Likelihood (ML) and Bayesian Inference (BI). A timeline was then placed on the divergence of lineages using a Bayesian relaxed molecular clock approach. Results: Phylogenetic analyses of sequenced data for three combined nuclear regions provided strong support for three major geographically defined clades: Holarctic, South American-Australasian and African. Molecular dating placed the initial radiation of the genus at 54 million years ago within the Early Paleogene, postdating the tectonic break-up of Gondwana. Conclusions: The distribution of extant Armillaria species is the result of ancient long-distance dispersal rather than vicariance due to continental drift. As these finding are contrary to most prior vicariance hypotheses for fungi, our result

Teachers Writing about Math: Exploring Inquiry in an Online Community

This study followed three elementary-school teachers as they engaged in online discussions about inquiry-based mathematics teaching, and wrote and tested inquiry lessons for their own classrooms. In an inquiry lesson, students bring their own knowledge to open-ended problem situations, and build on that knowledge as they try out solutions and share their ideas with others. Evidence from the study suggests that teachers may turn to inquiry as an antidote to the way they learned about mathematics as schoolchildren, and that participating in an online community is a way for teachers to gain new mathematical and pedagogical knowledge and to change their conceptual understanding of inquiry-based teaching. The study results indicate that online professional development can help teachers improve their practice, but that care must be taken to build social ties within the group, and to structure tasks in a way that encourages collaboration and constructive criticism.MAS

Mean BMI grade across tertiles of cardiorespiratory fitness.

<p>**Significantly different to “Middle” and “High” fitness group, p<0.01. *Significantly different to “”High” fitness groups, p<0.05.</p

Relationship between cardiorespiratory fitness, systolic blood pressure, body mass index, waist circumference and waist-height ratio.

<p>^aadjusted for age, sex and GMFCS level</p><p>^badjusted for age, sex, GMFCS level and BMI grade; zSBP, z-scores for systolic blood pressure</p><p>Relationship between cardiorespiratory fitness, systolic blood pressure, body mass index, waist circumference and waist-height ratio.</p

Mean waist-height ratio across tertiles of cardiorespiratory fitness.

<p>*Significantly different to “Middle” and “High” fitness groups, p<0.001.</p

Mean vigorous physical activity across tertiles of cardiorespiratory fitness.

<p>*Significantly different to “Middle” fitness group, p<0.05.</p

Characteristics of participants (n = 55).

<p>zSBP, z-scores for systolic blood pressure; zDBP, z-scores for diastolic blood pressure; GMFCS, Gross Motor Function Classification System</p><p>Characteristics of participants (n = 55).</p

Improving Power to Detect Changes in Blood miRNA Expression by Accounting for Sources of Variability in Experimental Designs

BACKGROUND: Blood microRNAs (miRs) are a new promising area of disease research, but variability in miR measurements may limit detection of true-positive findings. Here, we measured sources of miR variability and determine whether repeated measures can improve power to detect fold-change differences between comparison groups. METHODS: Blood from healthy volunteers (N=12) was collected at three time points. The miRs were extracted by a method predetermined to give the highest miR-yield. Nine different miRs were quantified using different qPCR assays and analyzed using mixed models to identify sources of variability. A larger number of miRs from a publicly-available blood miR microarray dataset with repeated measures was used for a bootstrapping procedure to investigate effects of repeated-measures on power to detect fold-changes in miR expression for a theoretical case-control study. RESULTS: Technical variability in qPCR replicates was identified as a significant source of variability (p<0.05) for all nine miRs tested. Variability was larger in the TaqMan qPCR assays (SD = 0.15–0.61) versus the qScript qPCR assays (SD = 0.08–0.14). Inter- and intra- individual and extraction variability also contributed significantly for two miRs. The bootstrapping procedure demonstrated that repeated measures (20–50% of N) increased detection of a 2-fold change for ~10–45% more miRs. CONCLUSION: Statistical power to detect small-fold changes in blood miRs can be improved by accounting for sources of variability using repeated measures and choosing appropriate methods to minimize variability in miR quantification. IMPACT: This study demonstrates the importance of including repeated measures in experimental designs for blood miR research