Analysis of the P. lividus sea urchin genome highlights contrasting trends of genomic and regulatory evolution in deuterostomes

Sea urchins are emblematic models in developmental biology and display several characteristics that set them apart from other deuterostomes. To uncover the genomic cues that may underlie these specificities, we generated a chromosome-scale genome assembly for the sea urchin Paracentrotus lividus and an extensive gene expression and epigenetic profiles of its embryonic development. We found that, unlike vertebrates, sea urchins retained ancestral chromosomal linkages but underwent very fast intrachromosomal gene order mixing. We identified a burst of gene duplication in the echinoid lineage and showed that some of these expanded genes have been recruited in novel structures (water vascular system, Aristotle's lantern, and skeletogenic micromere lineage). Finally, we identified gene-regulatory modules conserved between sea urchins and chordates. Our results suggest that gene-regulatory networks controlling development can be conserved despite extensive gene order rearrangement

External validation of a prediction model for estimating fat mass in children and adolescents in 19 countries: individual participant data meta-analysis

Objective To evaluate the performance of a UK based prediction model for estimating fat-free mass (and indirectly fat mass) in children and adolescents in non-UK settings. Design Individual participant data meta-analysis. Setting 19 countries. Participants 5693 children and adolescents (49.7% boys) aged 4 to 15 years with complete data on the predictors included in the UK based model (weight, height, age, sex, and ethnicity) and on the independently assessed outcome measure (fat-free mass determined by deuterium dilution assessment). Main outcome measures The outcome of the UK based prediction model was natural log transformed fat-free mass (lnFFM). Predictive performance statistics of R2, calibration slope, calibration-in-the-large, and root mean square error were assessed in each of the 19 countries and then pooled through random effects meta-analysis. Calibration plots were also derived for each country, including flexible calibration curves. Results The model showed good predictive ability in non-UK populations of children and adolescents, providing R2 values of >75% in all countries and >90% in 11 of the 19 countries, and with good calibration (ie, agreement) of observed and predicted values. Root mean square error values (on fat-free mass scale) were <4 kg in 17 of the 19 settings. Pooled values (95% confidence intervals) of R2, calibration slope, and calibration-in-the-large were 88.7% (85.9% to 91.4%), 0.98 (0.97 to 1.00), and 0.01 (−0.02 to 0.04), respectively. Heterogeneity was evident in the R2 and calibration-in-the-large values across settings, but not in the calibration slope. Model performance did not vary markedly between boys and girls, age, ethnicity, and national income groups. To further improve the accuracy of the predictions, the model equation was recalibrated for the intercept in each setting so that country specific equations are available for future use. Conclusion The UK based prediction model, which is based on readily available measures, provides predictions of childhood fat-free mass, and hence fat mass, in a range of non-UK settings that explain a large proportion of the variability in observed fat-free mass, and exhibit good calibration performance, especially after recalibration of the intercept for each population. The model demonstrates good generalisability in both low-middle income and high income populations of healthy children and adolescents aged 4-15 years

STRENGTH AND HANDEDNESS IN ADOLESCENTS: THE IMPACT OF SPORT PRACTICE ON LATERALITY CONSOLIDATION / FUERZA Y PREFERENCIA MANUAL EN ADOLESCENTES: EL IMPACTO DE LA PRÁCTICA DEPORTIVA EN LA CONSOLIDACIÓN DE LA LATERALIDAD

Handedness (upper limb laterality) should be a cornerstone of motor skill development and sport performance in youth. However, many environmental and social factors affect laterality consolidation (LC) during development. It was our aim to analyze the influence of out of school sport practice (OSSP) on LC. 249 adolescents from the same high school were selected for this study. Handedness was assessed by a laterality quotient (LQ) calculated from an adapted questionnaire. Handgrip isometric strength tests were carried out both left and right hand to confirm the dominance agreement with LQ. Right-handedness students showed higher right vs. left strength difference than left-handedness (2.25 and -0.91kg; P&lt;0.05). There were a higher proportion of LC in the group of adolescents with OSSP than those without OSSP, both in left (LH) and right-handedness (RH) (OSSP: RH, 80% and LH, 77.4% vs. non-OSSP: RH, 66.7% and L,H 41.7%; P&lt;0.05). Our main finding was that there was higher probability of LC among adolescents involved in OSSP. Also, a simple inventory and handgrip strength test may be useful tools in order to assess LC, which can help to reinforce laterality in adolescents. La preferencia manual (lateralidad del miembro superior) debería ser una parte fundamental del desarrollo de la competencia motora y el rendimiento deportivo durante la juventud. Sin embargo, existen numerosos factores sociales y medioambientales que afectan a la consolidación de la lateralidad (LC) durante el desarrollo. El objetivo de este estudio fue analizar la influencia de la práctica deportiva fuera de la escuela (OSSP) en la LC. Para ello 249 adolescentes del mismo Instituto de Educación Secundaria Obligatoria fueron seleccionados. La preferencia manual fue evaluada con el coeficiente de lateralidad (LQ) calculado utilizando un cuestionario especifico adaptado. Se realizó un test de fuerza isométrica de prensión manual derecha e izquierda para confirmar la concordancia con el LQ. Los estudiantes con preferencia manual derecha mostraron una diferencia de fuerza entre la mano derecha y la izquierda mayor que los del grupo de preferencia manual izquierda (2,25 and -0,91kg; P&lt;0,05). Hubo una mayor proporción de LC en el grupo de adolescentes con OSSP que en el grupo sin OSSP, tanto para zurdos (LF) como para diestros (RH) (OSSP: RH, 80% and LH, 77,4% vs. non-OSSP: RH, 66,7% and LH 41,7%; P&lt;0,05). Nuestro principal hallazgo fue, por tanto, el hecho de una mayor consolidación de la lateralidad entre los adolescentes del grupo que practicaba deporte. Además, un simple cuestionario y test de fuerza de prensión manual pueden ser buenas herramientas para evaluar la LC, lo cual puede ayudar a reforzar la lateralidad en adolescentes.   Article visualizations

External validation of a prediction model for estimating fat mass in children and adolescents in 19 countries: individual participant data meta-analysis

OBJECTIVE: To evaluate the performance of a UK based prediction model for estimating fat-free mass (and indirectly fat mass) in children and adolescents in non-UK settings. DESIGN: Individual participant data meta-analysis. SETTING: 19 countries. PARTICIPANTS: 5693 children and adolescents (49.7% boys) aged 4 to 15 years with complete data on the predictors included in the UK based model (weight, height, age, sex, and ethnicity) and on the independently assessed outcome measure (fat-free mass determined by deuterium dilution assessment). MAIN OUTCOME MEASURES: The outcome of the UK based prediction model was natural log transformed fat-free mass (lnFFM). Predictive performance statistics of R2, calibration slope, calibration-in-the-large, and root mean square error were assessed in each of the 19 countries and then pooled through random effects meta-analysis. Calibration plots were also derived for each country, including flexible calibration curves. RESULTS: The model showed good predictive ability in non-UK populations of children and adolescents, providing R2 values of >75% in all countries and >90% in 11 of the 19 countries, and with good calibration (ie, agreement) of observed and predicted values. Root mean square error values (on fat-free mass scale) were <4 kg in 17 of the 19 settings. Pooled values (95% confidence intervals) of R2, calibration slope, and calibration-in-the-large were 88.7% (85.9% to 91.4%), 0.98 (0.97 to 1.00), and 0.01 (-0.02 to 0.04), respectively. Heterogeneity was evident in the R2 and calibration-in-the-large values across settings, but not in the calibration slope. Model performance did not vary markedly between boys and girls, age, ethnicity, and national income groups. To further improve the accuracy of the predictions, the model equation was recalibrated for the intercept in each setting so that country specific equations are available for future use. CONCLUSION: The UK based prediction model, which is based on readily available measures, provides predictions of childhood fat-free mass, and hence fat mass, in a range of non-UK settings that explain a large proportion of the variability in observed fat-free mass, and exhibit good calibration performance, especially after recalibration of the intercept for each population. The model demonstrates good generalisability in both low-middle income and high income populations of healthy children and adolescents aged 4-15 years

External validation of a prediction model for estimating fat mass in children and adolescents in 19 countries: individual participant data meta-analysis

Peer reviewed: TrueAcknowledgements: We thank John Reilly for his advice on data sources and data access; Cara L Eckhardt, Josephine Avila, Igor Y Kon, and Jinzhong Wang from the Eckhardt et al study23; and all staff involved in recruitment and data collection from the included studies. Data gathered from South Africa was supported by South Africa Medical Research Council and National Research Foundation.Objective To evaluate the performance of a UK based prediction model for estimating fat-free mass (and indirectly fat mass) in children and adolescents in non-UK settings. Design Individual participant data meta-analysis. Setting 19 countries. Participants 5693 children and adolescents (49.7% boys) aged 4 to 15 years with complete data on the predictors included in the UK based model (weight, height, age, sex, and ethnicity) and on the independently assessed outcome measure (fat-free mass determined by deuterium dilution assessment). Main outcome measures The outcome of the UK based prediction model was natural log transformed fat-free mass (lnFFM). Predictive performance statistics of R2 , calibration slope, calibration-in-the-large, and root mean square error were assessed in each of the 19 countries and then pooled through random effects meta-analysis. Calibration plots were also derived for each country, including flexible calibration curves. Results The model showed good predictive ability in non-UK populations of children and adolescents, providing R2 values of >75% in all countries and >90% in 11 of the 19 countries, and with good calibration (ie, agreement) of observed and predicted values. Root mean square error values (on fat-free mass scale) were <4 kg in 17 of the 19 settings. Pooled values (95% confidence intervals) of R2 , calibration slope, and calibration-in-the-large were 88.7% (85.9% to 91.4%), 0.98 (0.97 to 1.00), and 0.01 (−0.02 to 0.04), respectively. Heterogeneity was evident in the R2 and calibration-in-the-large values across settings, but not in the calibration slope. Model performance did not vary markedly between boys and girls, age, ethnicity, and national income groups. To further improve the accuracy of the predictions, the model equation was recalibrated for the intercept in each setting so that country specific equations are available for future use. Co nclusion The UK based prediction model, which is based on readily available measures, provides predictions of childhood fat-free mass, and hence fat mass, in a range of non-UK settings that explain a large proportion of the variability in observed fat-free mass, and exhibit good calibration performance, especially after recalibration of the intercept for each population. The model demonstrates good generalisability in both low-middle income and high income populations of healthy children and adolescents aged 4-15 year