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The authors' aim in this cross-sectional study was to characterize levels of objectively measured physical activity and sedentary time in adolescents from 9 European countries. The study comprised 2,200 European adolescents (1,184 girls) participating in the HELENA cross-sectional study (2006-2008). Physical activity was measured by accelerometry and was expressed as average intensity (counts/minute) and amount of time (minutes/day) spent engaging in moderate- to vigorous-intensity physical activity (MVPA). Time spent in sedentary behaviors was also objectively measured. Cardiorespiratory fitness was measured by means of the 20-m shuttle run test. Level of maternal education was reported by the adolescents. A higher proportion of boys (56.8% of boys vs. 27.5% of girls) met the physical activity recommendations of at least 60 minutes/day of MVPA. Adolescents spent most of the registered time in sedentary behaviors (9 hours/day, or 71% of the registered time). Both average intensity and MVPA were higher in adolescents with high cardiorespiratory fitness, and sedentary time was lower in the high-fitness group. There were no physical activity or sedentary time differences between maternal education categories. These data provide an objective measure of physical activity and amount of time spent in sedentary behaviors in a relatively large number of European adolescents.

Objectives: Nutritional factors in early life may have long-term physiologic effects in humans. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) play important roles in protecting against cardiovascular disease (CVD) risk. Our aim was to examine the association of birth weight (BW) with serum long chain polyunsaturated fatty acids (LCPUFA) profile in adolescents., Subjects and Methods: A total of 772 European adolescents (56.3% females) aged 14.7 ± 1.2 years were included in this study. Information on BW and gestational age was obtained from parental records. DHA, EPA and arachidonic acid (AA) concentrations were measured in serum phospholipids. Alfa-linolenic (ALA), linoleic (LA), AA, EPA and DHA intakes assessed by a computer based 24h dietary recall. Gender, gestational age, pubertal status, body mass index, center and total energy and LCPUFA intakes were used as confounders in all the analyses., Results: BW was significantly associated with serum DHA and EPA (both adjusted P<0.05) independently of potential confounders including their main dietetic source. We did not observe any significant relationship between BW and serum AA levels., Conclusions: Our findings suggest that early metabolic changes, as a result from prenatal environmental influences, could affect long chain polyunsaturated fatty acid metabolism later in life. These results may contribute to explain the relationship between early nutrition and growth and later metabolic disorders as CVD., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

The aim of this study was to examine the interrater reliability (trained vs. untrained raters) and criterion-related validity (manual vs. automatic timing) of the 4 × 10-m shuttle run and 30-m running speed tests (times measured). The study comprised 85 adolescents (38 girls) aged 13.0-16.9 years from the Healthy Lifestyle in Europe by Nutrition in Adolescence study. The time required to complete the 4 × 10-m shuttle run and 30-m running tests was simultaneously measured (a) manually with a stopwatch by both trained and untrained raters (for interrater reliability analysis), and (b) by using photoelectric cells (for validity analysis). Systematic error, random error, and heteroscedasticity were studied with repeated-measured analysis of variance and Bland-Altman plots. The systematic error for untrained vs. trained raters and the untrained raters vs. photoelectric cells were in all cases ∼0.1 seconds (p < 0.01), that is, untrained raters recorded higher times. No systematic error was found between trained raters and photoelectric cells (p > 0.05). No heteroscedasticity was shown in any case (p > 0.05). The findings indicate that manual measurements by a trained rater, using a stopwatch, seem to be a valid method to assess speed and agility fitness testing in adolescents. Researchers must be trained to minimize the measurement error.

Background: An adequate nutritional status of antioxidant vitamins (vitamins A, C, E) and b-carotene is essential especially during childhood and adolescence, because of their important roles in cell growth and development. Currently, there are no physiological reference values for blood concentration of these vitamins and b-carotene in apparently healthy European adolescents. The aim of the current study was to obtain reliable and comparable data of antioxidant vitamins and b-carotene in a cross-sectional study, within HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence), which was conducted in a representative sample of adolescents from ten European cities., Material and Methods: From a subsample of 1,054 adolescents (males= 501) of the HELENA Cross Sectional Study with an age range of 12.5 to 17.49 years, fasting blood samples were taken and analyzed for vitamins A, E, C, and b-carotene status. As specific reference values for adolescents are missing, percentile distribution by age and sex is given., Results: Mean concentrations were the following: Retinol: 356.4 ± 107.9 cm/mL; alpha-tocopherol: 9.9 ± 2.1 microg/mL; vitamin C: 10.3 ± 3.3 mg/L; and b-carotene: 245.6 ± 169.6 cm/mL. Females showed higher alpha-tocopherol and vitamin C values compared with males and 17-year-old boys had higher retinol levels than the same-aged girls (p = 0.018). Retinol serum concentrations increased significantly according to age in both gender, but girls had also significantly increasing b-carotene levels by age., Conclusions: For the first time, concentrations of antioxidant vitamins and pro-vitamin beta-carotene have been obtained in a representative sample of apparently healthy European adolescents. These data can contribute to the establishment of reference ranges in adolescents.

Two rate-limiting enzymes in PUFA biosynthesis, Δ5- and Δ6-desaturases, are encoded by the FADS1 and FADS2 genes, respectively. Genetic variants in the FADS1-FADS2 gene cluster are associated with changes in plasma concentrations of PUFA, HDL- and LDL-cholesterol, and TG. However, little is known about whether dietary PUFA intake modulates these associations, especially in adolescents. We assessed whether dietary linoleic acid (LA) or α-linolenic acid (ALA) modulate the association between the FADS1 rs174546 polymorphism and concentrations of PUFA, other lipids, and lipoproteins in adolescents. Dietary intakes of LA and ALA, FADS1 rs174546 genotypes, PUFA levels in serum phospholipids, and serum concentrations of TG, cholesterol, and lipoproteins were determined in 573 European adolescents from the HELENA study. The sample was stratified according to the median dietary LA (≤9.4 and >9.4 g/d) and ALA (≤1.4 and >1.4 g/d) intakes. The associations between FADS1 rs174546 and concentrations of PUFA, TG, cholesterol, and lipoproteins were not affected by dietary LA intake (all P-interaction > 0.05). Similarly, the association between the FADS1 rs174546 polymorphism and serum phospholipid concentrations of ALA or EPA was not modified by dietary ALA intake (all P-interaction > 0.05). In contrast, the rs174546 minor allele was associated with lower total cholesterol concentrations (P = 0.01 under the dominant model) and non-HDL-cholesterol concentrations (P = 0.02 under the dominant model) in the high-ALA-intake group but not in the low-ALA-intake group (P-interaction = 0.01). These results suggest that dietary ALA intake modulates the association between FADS1 rs174546 and serum total and non-HDL-cholesterol concentrations at a young age.

Study Objectives: To investigate differences and a possible effect modification by geographical region in the association between sleep duration and overweight., Design: Cross-sectional., Setting: Primary schools and preschools in 8 European countries., Participants: 7867 children aged 2 to 9 years., Interventions: Not applicable., Measurements: Nocturnal sleep duration was assessed as part of a parental 24-h recall. Height and weight were measured by standardized procedures across centers. Data on personal, social, environmental and behavioral factors were collected using a standardized parental questionnaire., Results: Sleep duration differed (P < 0.001) between European regions and normal vs. overweight children. A dose-dependent inverse association between sleep duration and overweight could be seen, with crude odds ratios ranging from 1.73 (99% CI 1.33; 2.25) for sleeping between 10 and 11 h to 3.81 (99% CI 2.85; 5.09) for sleeping less than 9 h (reference category > 11 h). This persisted after adjustment, but remained significant only for sleeping less than 9 h per night (north: OR = 1.70; 99% CI 1.13; 2.58 vs. south: OR = 2.84; 99% CI 1.57; 5.12) if stratified by region. No effect modification by region could be found, but adjustment for region accounted for changes in the effect estimate for sleeping less than 9 h (OR = 2.22; 99% CI 1.64; 3.02). The association was stronger in school children than in preschool children., Conclusion: Geographic region and related aspects-even if they do not seem to modify the association between sleep and overweight-should in any case be taken in consideration as a confounding factor on this association.

Background: We examined: (i) the usefulness of the International Fitness Scale (IFIS) to correctly rank adolescents into physical fitness levels; (ii) the capacity of the IFIS for predicting cardiovascular disease (CVD) risk; and (iii) the reliability of the IFIS in adolescents., Methods: The study comprised 3059 adolescents (aged 12.5-17.5 years) from nine European countries (HELENA study). Blood samples were collected in one-third of the participants (randomly selected, n = 981). Test-retest reliability of the IFIS was studied in a separate sample of 277 adolescents. Physical fitness-cardiorespiratory fitness (CRF), muscular fitness (MF), speed-agility (SP-AG), flexibility and overall fitness-was self-reported using 5-point Likert-scale questions (1 = very poor, 5 = very good) and measured using standard field-based tests. The CVD risk factors measured included total/central adiposity indices and mean arterial pressure, total and high density lipoprotein cholesterol, triglycerides, insulin resistance (HOMA) and C-reactive protein., Results: Analysis of covariance showed that adolescents reporting better fitness had higher measured fitness levels for all the variables studied (all P < 0.001), regardless of gender, age and weight status. Adolescents reporting very good overall fitness, CRF and SP-AG had a healthier cardiovascular profile in eight out of nine CVD risk factors studied. Perfect agreement (same test-retest answer) was observed in 65% of the adolescents and perfect-acceptable agreement (same answer or ±1) in 97% of the adolescents., Conclusions: (i) The IFIS is able to correctly rank adolescents according to their measured physical fitness levels; (ii) adolescents reporting a good/very good overall fitness, CRF or SP-AG have a more favorable cardiovascular profile; and (iii) The IFIS is reliable in adolescents.

The aim of the current study was to compare the association of several anthropometric indices, with insulin resistance (IR) proxy measures in European adolescents. The present study comprises 1,097 adolescents aged 12.5-17.5 from ten European cities participating in the HELENA study. Weight, height, waist circumference (WC) and hip circumference, skinfolds thickness, fat mass (FM), fasting plasma glucose (G(F)) and serum insulin (I(F)) levels were measured. HOMA (as indicator of IR body mass index (BMI), waist to hip ratio (WHR) and waist to height ratio (WHtR) were calculated. I(F) and HOMA were statistically significantly related to BMI, WC, skinfold sum, WHtR, WHR and FM. BMI, WC, WHtR, skinfold sum and FM displayed similar correlation with I(F) and HOMA as opposed to WHR where lower correlation with IR indices was detected in the overall sample. Similar results were found for boys, girls and underweight/normal weight adolescents. On the other hand, WC and WHtR were found to be more strongly associated with IR proxy measures compared to the rest of anthropometric indices among overweight/obese subjects. Based on the current findings, WC and WHtR could be used, alternatively, to identify the overweight/obese adolescent at risk for developing IR. In addition, all aforementioned anthropometric indices, except WHR, could be used among the underweight/normal weight adolescents.

Study Objectives: To compare nocturnal sleep duration in children from 8 European countries and identify its determinants., Design: Cross-sectional., Setting: Primary schools and preschools participating in the IDEFICS study., Participants: 8,542 children aged 2 to 9 years from 8 European countries with complete information on nocturnal sleep duration., Interventions: Not applicable., Measurements: Nocturnal sleep duration was assessed by means of a computer based parental 24-h recall. Data on personal, social, environmental, and behavioral factors were collected by means of standardized parental questionnaire. Physical activity was surveyed with accelerometers., Results: Nocturnal sleep duration in the participating countries ranged from 9.5 h (SD 0.8) in Estonia to 11.2 h (SD 0.7) in Belgium and differed significantly between countries (P < 0.001) in univariate as well as in multivariate analyses, with children from northern countries sleeping the longest. Sleep duration decreased by about 6 min with each year of age over all countries. No effect of season, daylight duration, overweight, parental education level, or lifestyle factors could be seen., Conclusion: Sleep duration differs significantly between countries. Our findings allow for the conclusion that regional affiliation, including culture and environmental characteristics, seems to overlay individual determinants of sleep duration.

We assessed commuting patterns in adolescents from 10 European cities and examined associations with physical activity (PA). A total of 3112 adolescents were included. PA was objectively measured with accelerometry. Commuting patterns and overall PA were self-reported using questions from the International Physical Activity Questionnaire modified for adolescents (IPAQ-A). Adolescents reported to spend 30 min (15,60) [expressed as median (25th, 75th percentiles)] walking. In boys, associations between active commuting (walking and biking) and PA levels were observed for moderate, moderate-to-vigorous and overall PA. In girls, these associations were observed for moderate and moderate-to-vigorous PA (walking). Similar results were found with the IPAQ-A. We observed positive associations between overall commuting and PA levels in European adolescents, yet due to the cross-sectional study design we cannot state the direction of these. Future studies should address the causation between active commuting and PA levels.

Objective: Genetic variability in the NR1H3 gene (encoding LXRα) and in several of its target genes is associated with serum HDL-cholesterol (HDL-C) concentrations. We sought to assess if these associations could be detected in adolescents., Methods: Thirty-nine polymorphisms in NR1H3, ABCA1, APOE, CETP, PLTP and LPL were analysed in the HELENA study (n = 1144 European adolescents)., Results: The minor alleles of rs11039155 in NR1H3, rs2575879 in ABCA1, rs708272, rs17231506 and rs5882 in CETP and rs328 in LPL were associated with higher serum HDL-C concentrations (p ≤ 0.0012). The minor alleles of rs12221497 in NR1H3, rs1800978 in ABCA1 and the APOE ɛ4 allele were associated with lower HDL-C concentrations (p ≤ 0.01). The combined set of associated polymorphisms accounted for ∼6.6% of the variance in HDL-C., Conclusion: We report for the first time that polymorphisms in NR1H3 and its target genes ABCA1, APOE, CETP and LPL contribute to the genetic variance for HDL-C concentrations in adolescence., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Background: The aims of this study were to examine what amount of sedentary time is associated with low cardiorespiratory fitness (CRF) in adolescents and whether this association is independent of physical activity., Methods: The study comprised 1808 adolescents aged 12.5-17.5 years from 10 European cities. Sedentary time and moderate-to-vigorous physical activity (MVPA) were measured by accelerometer. CRF was assessed by the 20 m shuttle-run test. Adolescents were divided into two groups (high/low) according to FITNESSGRAM guidelines. Receiver-operating characteristic (ROC) analysis was used to determine thresholds that best discriminate between high and low CRF in adolescents., Results: Adolescent girls had more sedentary time than boys (p<0.001). ROC analysis showed that girls spending ≥69% of waking time in sedentary activities had low CRF, but no significant threshold discriminated between high and low CRF in boys. Adolescent girls who exceeded this threshold had lower levels of CRF (p≤0.001) and were more likely to have a low CRF (OR 1.68, 95% CI 1.22 to 2.31) independent of centre, age and body mass index. The negative influence of excessive sedentary time on CRF remained significant (p=0.045) in adolescent girls who did not meet the physical activity guidelines (<60 min/day in MVPA) but was abolished (p>0.05) in those who met the recommendation (≥60 min/day in MVPA)., Conclusion: Excessive sedentary time is associated with low CRF in adolescent girls but not in boys. However, this adverse effect might be attenuated if adolescent girls meet the current physical activity guidelines.

It has been suggested that breast-feeding (BF) may be associated with a decreased risk of cardiovascular disease in adulthood. A low-grade inflammation is associated with an increased risk of cardiovascular disease, even in apparently healthy children. The objective of this study was to assess the potential modulating effect of BF on the inflammatory status of healthy adolescents. Information on BF (duration) was obtained from parental records in 484 of 1040 healthy European urban adolescents (56.4% females) that had a blood sample obtained as part of the Healthy Lifestyle in Europe by Nutrition and Adolescence study. Blood serum inflammatory markers were measured, including high sensitivity C-reactive protein, complement factors 3 and 4, ceruloplasmin, adhesion molecules (L-selectin and soluble endothelial selectin, soluble vascular cell adhesion molecule 1, and intercellular adhesion molecule 1), cytokines, TGFβ1, and white blood cells. After univariate analysis, a propensity score, including the potential confounding factors, was computed and used to assess the association between BF and selected inflammatory markers. BF was not significantly associated with any of the selected inflammatory markers after adjustment for gender and propensity score. In our study, BF was not associated with low-grade inflammatory status in healthy adolescents, suggesting that the potential cardiovascular benefits of BF are related to other mechanisms than modulation of inflammation or might become relevant at a later age. Groups at high risk for cardiovascular disease should be a target for further research concerning the effects of BF.

Objective: to examine the association of healthrelated physical fitness with total and central body fat in adolescents., Participants/methods: the present cross-sectional study comprises 363 Spanish adolescents (186 female participants) aged 12.5-17.5 years. We assessed fitness by the 20-m shuttle run test (cardiorespiratory fitness); the handgrip strength, the standing broad jump and the Abalakov tests (muscular strength); and the 4 × 10-m shuttle run test (speed-agility). Total body fat was measured by dual energy x-ray absorptiometry (DXA), BodPod and sum of six skinfolds, and central body fat was measured by DXA at three regions (R1, R2 and R3) and waist circumference., Results: the Abalakov, the standing broad jump, the 4 × 10-m shuttle run and the 20-m shuttle run tests were negatively associated with all markers of total and central body fat in men and women after controlling for age, pubertal status and objectively assessed physical activity (p<0.01). Handgrip strength test was positively associated with waist circumference (p<0.01)., Conclusions: lower body muscular strength and cardiorespiratory fitness are negatively and consistently associated with total and central body fat in adolescents, whereas levels of upper body muscular strength were superior in adolescents with higher levels of central body fat.

Although numbers of older people are increasing, nursing students have negative attitudes towards older people and do not plan to care for them following graduation. Multiple strategies have been implemented to reverse students' attitudes with mixed results. The purpose of this pilot quasi-experimental study was to test a Creative-Bonding Intervention (CBI) with students implementing art activities with older people to promote students' willingness to take care of them. Using a self-transcendence conceptual framework, control (n = 56) and experimental (n = 14) student groups were pre- and post-tested on attitudes toward older people, self-transcendence, and willingness to serve. The CBI improved attitudes towards older people with negative attitudes significantly changed (P = .008) but with no significant differences on self-transcendence and willingness to serve. However, willingness to serve results approached significance (P = .08). The willingness measure (one question) should be expanded. Curricula changes that incorporate creative activities such as the CBI with larger and equal numbers in student groups and longitudinal follow up to determine long-term results after graduation are suggested.

Objective: To report sex- and age-specific physical fitness levels in European adolescents., Methods: A sample of 3428 adolescents (1845 girls) aged 12.5-17.49 years from 10 European cities in Austria, Belgium, France, Germany, Greece (an inland city and an island city), Hungary, Italy, Spain and Sweden was assessed in the Healthy Lifestyle in Europe by Nutrition in Adolescence study between 2006 and 2008. The authors assessed muscular fitness, speed/agility, flexibility and cardiorespiratory fitness using nine different fitness tests: handgrip, bent arm hang, standing long jump, Bosco jumps (squat jump, counter movement jump and Abalakov jump), 4×10-m shuttle run, back-saver sit and reach and 20-m shuttle run tests., Results: The authors derived sex- and age-specific normative values for physical fitness in the European adolescents using the LMS statistical method and expressed as tabulated percentiles from 10 to 100 and as smoothed centile curves (P₅, P₂₅, P₅₀, P₇₅ and P₉₅). The figures showed greater physical fitness in the boys, except for the flexibility test, and a trend towards increased physical fitness in the boys as their age increased, whereas the fitness levels in the girls were more stable across ages., Conclusions: The normative values hereby provided will enable evaluation and correct interpretation of European adolescents' fitness status.

We examined the association between the FTO rs9939609 polymorphism and serum leptin concentrations in adolescents. The FTO rs9939609 polymorphism was genotyped, and fasting serum leptin and insulin were measured in 655 European adolescents (365 females) aged 14.6 ± 1.2 years. We measured weight, height, triceps and subscapular skinfolds and waist circumference, and body fat percentage was calculated. Sex, pubertal status, center, physical activity (accelerometry), total or central adiposity and serum insulin concentrations were entered as confounders in the analyses. The minor A allele of the FTO rs9939609 was significantly associated with higher serum leptin concentrations independently of potential confounders including adiposity (+3.9 ng ml(-1) per risk allele (95% confidence interval: 2.0, 5.9); adjusted P < 0.001). These findings could link the FTO gene with serum leptin and consequently with the control of energy balance. Leptin could be a possible intermediary contributing to the association between the FTO rs9939609 polymorphism and adiposity.

The Drosophila transcription factor Tramtrack (Ttk) is involved in a wide range of developmental decisions, ranging from early embryonic patterning to differentiation processes in organogenesis. Given the wide spectrum of functions and pleiotropic effects that hinder a comprehensive characterisation, many of the tissue specific functions of this transcription factor are only poorly understood. We recently discovered multiple roles of Ttk in the development of the tracheal system on the morphogenetic level. Here, we sought to identify some of the underlying genetic components that are responsible for the tracheal phenotypes of Ttk mutants. We therefore profiled gene expression changes after Ttk loss- and gain-of-function in whole embryos and cell populations enriched for tracheal cells. The analysis of the transcriptomes revealed widespread changes in gene expression. Interestingly, one of the most prominent gene classes that showed significant opposing responses to loss- and gain-of-function was annotated with functions in chitin metabolism, along with additional genes that are linked to cellular responses, which are impaired in ttk mutants. The expression changes of these genes were validated by quantitative real-time PCR and further functional analysis of these candidate genes and other genes also expected to control tracheal tube size revealed at least a partial explanation of Ttk's role in tube size regulation. The computational analysis of our tissue-specific gene expression data highlighted the sensitivity of the approach and revealed an interesting set of novel putatively tracheal genes., (© 2011 Rotstein et al.)

Objectives: The purpose of this study was to determine the sex-specific physical activity (PA) intensity thresholds that best discriminate between unhealthy/healthy cardiorespiratory fitness (CRF)., Methods: Participants included 1,808 adolescents (964 girls), aged 12.5-17.5 years, from the HELENA study. We measured PA by accelerometer and calculated the time spent at light, moderate, vigorous, and moderate-to-vigorous (MVPA) intensities. CRF was assessed by the 20-m shuttle-run test. Adolescents were dichotomized (unhealthy/healthy) based on sex- and age-specific FITNESSGRAM standards. Receiver operating characteristic (ROC) analysis was used to determine thresholds that best discriminate between CRF categories., Results: ROC analyses revealed that the PA thresholds that best discriminate between unhealthy/healthy CRF were ≥152, ≥33, ≥13, and ≥52 min/day in light, moderate, vigorous, and MVPA, respectively. In boys, the PA thresholds associated with a healthy CRF were ≥37, ≥19, and ≥56 min/day in moderate, vigorous, and MVPA, respectively, whereas in girls were ≥152, ≥34, ≥12, and ≥51 min/day in light, moderate, vigorous, and MVPA, respectively. Spending at least 60 min/day in MVPA was also associated with a healthy CRF (odds ratios: 1.75, 1.94, and 1.57, all P < 0.05, for the whole sample, boys, and girls, respectively)., Conclusions: This study shows sex- and intensity-specific PA thresholds to discriminate between adolescents with a healthy CRF from those with a less favorable or unhealthy CRF level., (© 2010 Wiley-Liss, Inc.)

Our aim in this study was to examine the association between breastfeeding duration and cardiorespiratory fitness, isometric strength, and explosive strength during adolescence. A total of 2567 adolescents (1426 girls) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) cross-sectional study aged 12.5-17.5 y were included. Information about duration of any and exclusive breastfeeding was obtained retrospectively by means of a parental questionnaire. The 20-m shuttle run, handgrip strength, and standing long jump tests were used to assess physical fitness. Significant differences among the categories of breastfeeding duration were tested using ANCOVA after adjusting for a set of potential confounders: gestational and current age, birth weight, sexual maturation, fat mass, fat-free mass, maternal education, parental weight status, country, smoking behavior, and days of vigorous physical activity. Longer breastfeeding (either any or exclusive) was associated with a higher performance in the standing long jump test in both boys and girls (P < 0.001), regardless of fat mass, fat-free mass, and the rest of potential confounders. In adolescents who were breastfed for 3-5 mo or ≥6 mo, the risk of having a standing long jump performance below the 5th percentile was reduced by half compared with those who were never breastfed [odds ratio (OR) = 0.54, 95% CI = 0.30-0.96, P < 0.05; and OR = 0.40, 95% CI = 0.22-0.74, P < 0.01, respectively). These findings suggest a role of breastfeeding in determining lower body explosive strength during adolescence.

Background: It is unclear how much physical activity is necessary to prevent obesity during adolescence., Purpose: The purpose of this study was to examine whether the current physical activity guidelines for youth are associated with a lower risk of excess of body fat in European adolescents., Methods: A sample of 2094 adolescents from the HELENA cross-sectional study was selected. Levels of moderate, vigorous, and moderate to vigorous physical activity (MVPA) were assessed using accelerometers. BMI and percentage of body fat (skinfolds) were calculated and used to categorize the adolescents as normal-weight/normal-fat, overweight/overfat, and obese. Data were collected during 2006-2007. Receiver operating characteristic (ROC) analysis, performed in 2009, was used to determine thresholds that best discriminate between weight and body fat categories., Results: ROC analysis showed that >/=18 minutes/day in vigorous physical activity and >/=55 minutes/day in MVPA significantly discriminated between normal-weight and overweight+obesity categories. Moreover, >/=9 minutes/day of vigorous physical activity and >/=49 minutes/day of MVPA discriminated between normal-fat and overfat/obese adolescents. Adolescents who did not meet the current physical activity guidelines for youth of 60 minutes/day in MVPA increased the risk of having overweight+obesity (OR=1.24, 95% CI=1.01, 1.534) and overfat+obesity (OR=1.79, 95% CI=1.33, 2.42). ORs increased when adolescents did not meet the guidelines of at least 15 minutes/day in vigorous physical activity., Conclusions: Current physical activity guidelines seem to be appropriate to prevent excess of body fat in European adolescents. However, participation in vigorous physical activity might have additional importance in preventing obesity., (2010 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: To describe sedentary behaviors in adolescents and to examine the influence of media availability on TV viewing., Method: The study assessed 3278 adolescents (1537 males and 1741 females, 12.5-17.5 years) involved in the HELENA study (2007). Adolescents reported hours of TV viewing, computer games, console, internet for study and non-study reasons, and study, as well as availability of TVs, computers and consoles., Results: Time spent in sedentary behaviors was higher during weekends (all p<0.001). Males spent more hours on TV viewing (for > or = 15 years at weekends), playing computer games and console games while females spent more time studying and surfing for non-study reasons. During weekdays, one third of adolescents exceeded the screen time guidelines (>2h/day) based solely on TV viewing, whereas around 60% exceeded it at weekends. Having a TV or a console in the bedroom was associated with higher TV viewing (OR=2.66; 95% CI 2.23-3.18; and OR=1.92; 95% CI 1.61-2.28, respectively) whereas the presence of computer reduced it (OR=0.57; 95% CI 0.48-0.68)., Conclusion: Adolescents living in Europe are not meeting media recommendations, especially during weekend. The absence of a TV in the adolescents' bedroom might reduce TV viewing. Further studies are needed to confirm or contrast our findings., (Copyright 2010 Elsevier Inc. All rights reserved.)

Objective: To describe the standardization process and reliability of anthropometric and bioelectrical impedance analysis (BIA) measurements. We examined both intra- and interobserver errors for skinfolds, circumferences and BIA., Methods: For the intraobserver error assessment, first of all, 202 adolescents in the pilot study (110 boys, 92 girls, aged 13.64+/-0.78 years) were assessed. For the second intraobserver and interobserver assessments, 10 adolescents were studied (5 boys and 5 girls)., Results: The pilot study's intraobserver technical errors of measurement (TEMs) were between 0.12 and 2.9 mm for skinfold thicknesses, and between 0.13 and 1.75 cm for circumferences. Intraobserver reliability for skinfold thicknesses was greater than 69.44% and beyond 78.43% for circumferences. The final workshop's intraobserver TEMs for skinfold thicknesses and circumferences were smaller than 1; for BIA resistance TEMs were smaller than 0.1 Omega and for reactance they were smaller than 0.2 Omega. Intraobserver reliability values were greater than 95, 97, 99 and 97% for skinfold thicknesses, circumferences, BIA resistance and reactance, respectively. Interobserver TEMs for skinfold thicknesses and circumferences ranged from 1 to 2 mm; for BIA they were 1.16 and 1.26 Omega for resistance and reactance, respectively. Interobserver reliability for skinfold thicknesses and circumferences were greater than 90%, and for BIA resistance and reactance they were greater than 90%., Conclusions: After the results of the pilot study, it was necessary to optimize the quality of the anthropometric measurements before the final survey. Significant improvements were observed in the intraobserver reliabilities for all measurements, with interobserver reliabilities being higher than 90% for most of the measurements.The Healthy Lifestyle in Europe by Nutrition in Adolescence Study aims to describe total body fat percentage and anthropometric indices of body fat distribution in European adolescents.

Rationale: Environmental factors such as dietary habits, breastfeeding, socioeconomic conditions and educational factors are strong influences on nutritional and puberty status, physical activity, food choices and their interactions. Several diseases of adulthood seem to be linked to, or to originate from, lifestyle in childhood and adolescence., Objective: The aims of this study are to describe birth parameters and socioeconomic factors and to assess clinical status in adolescents aged 13-16 years from 10 European countries participating in the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Cross-Sectional Study (CSS)., Methodology: A self-report questionnaire on the socioeconomic status, a parental questionnaire concerning neonatal period and also a case report form (CRF), in which clinical items during clinical examination (such as medical history, treatments, anthropometry, Tanner staging, blood pressure, heart rate) were assessed. To develop these documents, first a list of items was established, a search of existing documents was performed and the advice of local and international experts was taken. All documents (questionnaires and an operations manual) were discussed in plenary HELENA meetings; a final version of these documents was fixed, and the process of translation and back translation was performed., Results: The questionnaires and CRF were tested for validation in all 10 participant cities; 208 adolescents were enrolled during the pilot study. All items that caused problems or questions in one or more participating centers or were completed by < 85% of the adolescents were reviewed before the beginning of the HELENA-CSS., Conclusion: These final questionnaires and CRF will contribute to better understanding of the inequalities in nutrition, behavior and health in the European adolescent population. The experience and process should be useful for other multicenter studies.

Rationale: Research involving humans is regulated by regulatory authorities through their specific requirements and controls. The Healthy Life Style in Europe by Nutrition in Adolescence Cross-Sectional Study (HELENA-CSS) is a multicenter biomedical research study of adolescents in several representative European cities, which requires satisfying medico-regulatory requirements including Independent Ethics Committee (IEC) approval and agreement by the national or local regulatory authorities. To achieve a high level of quality assurance relating to ethical issues, we followed the good clinical practices (GCP) described at the International Conference on Harmonisation (ICH), which we adapted to the national and local situations of each of the 11 participating cities in 10 European countries., Objective: The main objective of the HELENA-CSS is to evaluate reliable and comparable data of nutritional habits and lifestyle in a representative sample of European adolescents. The aim of this paper is to present the methods relating to the ethical and regulatory issues of this study and to describe the current state of the medico-regulatory requirements involved in conducting this kind of study in each country., Materials and Methods: Following the GCP-ICH guidelines, a protocol describing the HELENA-CSS was written and approved by all partners. In the pilot study, a case report form adapted to the study objectives and its manual of operation was constructed and used by all partners. All information letters to adolescents and their parents and consent forms were first written in English, then translated into the local language, and adapted to each local situation. All documents were then checked centrally for any deviation and corrected if required. An operation manual relating to ethical issues and other medico-regulatory requirements was also developed. This paper presents the current status of the medico-regulatory requirements from each HELENA-CSS participant country., Results: Before the beginning of the study, most centers had satisfied the medico-regulatory requirements of IEC approval and agreement with other national or local regulatory authorities/organizations. For a few centers, some problems were detected and corrective actions were taken to improve missing information to reach a high level of quality assurance of ethical issues., Conclusion: The GCP-ICH guidelines about nontherapeutic biomedical research are interpreted and applied differently across Europe. This study shows that high-quality nontherapeutic biomedical research can address the ethical issues included in the GCP-ICH regulations and can be harmonized among the HELENA European partners.

Unlabelled: There is increasing evidence that obesity may damage the kidney in otherwise healthy individuals. Our study investigated the effect of childhood obesity on urinary albumin and beta-2-microglobulin excretion, and the association of these with obesity-related cardiovascular risk factors. Random morning spot urine samples were collected from clinically healthy obese (n = 86; median age 12.9 years, range 8.9-17.2 years; median weight 80.6 kg, range 46.1-136.8 kg; median body mass index 30.4 kg/m2, range 24.5-43.2 kg/m2) and normal weight children (n = 79; median age 13.5 years, range 10.7-14.9 years; median weight 51.0 kg, range 27.3-72.5 kg; median body mass index 18.2 kg/m2, range 13.2-23.9 kg/m2). The obese children were examined for the presence of common obesity-related cardiovascular risk factors including hyperinsulinaemia, impaired glucose tolerance (IGT), dyslipidaemia, hypercholesterolaemia, and hypertension. Obese children had a significantly higher urinary albumin/creatinine ratio (U-ACR) (median 11.7 mg/g, interquartile range 12.9 mg/g versus median 9.0 mg/g, interquartile range 5.1 mg/g; P = 0.003) and urinary beta-2-microglobulin/creatinine ratio (U-BMCR) (median 63.9 microg/g, interquartile range 34.7 microg/g versus median 34.6 microg/g, interquartile range 44.1 microg/g; P < 0.001) than normal weight children. Among the obese children, the U-ACR was associated with fasting hyperinsulinaemia, IGT, and hypercholesterolaemia (all P < 0.05), and significantly correlated with the fasting (r = 0.23, P < 0.05) and 2-h (r = 0.37, P < 0.001) plasma glucose levels measured during an oral glucose tolerance test. Obese children with no more than one of the features of the metabolic syndrome had significantly lower U-ACRs than obese children with two or more features (median 10.4 mg/g, interquartile range 5.8 mg/g versus median 15.3 mg/g, interquartile range 14.9 mg/g; P < 0.05)., Conclusion: According to our results, clinically healthy obese children have a higher degree of albuminuria and beta-2-microglobulinuria than normal weight children, indicating early renal glomerular and tubular dysfunction as a consequence of childhood obesity. The urinary albumin/creatinine ratio in the obese children was associated with certain metabolic derangements linked to obesity, and also with the clustering of features of the metabolic syndrome.

Coarse grained Langevin-type effective field equations may provide some guidance for the analysis of mesoscopic or microscopic molecular systems exhibiting fluctuations, or for systems of hundreds to thousands of atomic or subatomic particles produced in atomic or high-energy nuclear collisions. Suggestions for consistent realization of random fluctuations in discretized fluid dynamics will be presented.

Energy metabolism was measured in children receiving long-term treatment with valproic acid. In 8 of 10 randomly selected subjects, the resting respiratory quotient was higher than in age- and sex-matched control subjects (0.91 +/- 0.01 vs 0.87 +/- 0.01; p < 0.05). A shift was observed in fuel consumption, and a significant reduction was found in the amount of fats oxidized (0.68 +/- 0.23 vs 1.18 +/- 0.18 gm.kg-1.day-1), which was accompanied by increased utilization of carbohydrates (5.31 +/- 0.79 vs 3.81 +/- 0.39 gm.kg-1.day-1) in comparison with the control subjects. The resting total energy expenditure was not affected by the treatment. The children with an altered energy consumption pattern (n = 8) received carnitine supplementation for a month; the respiratory quotient then decreased (0.87 +/- 0.02), the oxidation of fats increased (1.42 +/- 0.25), and the consumption of carbohydrates decreased (3.87 +/- 0.79), but no changes in resting energy expenditure were observed. We conclude that carnitine depletion, a known adverse effect of valproic acid administration, may result in inhibited fatty acid oxidation, leading to a shift of substrates utilized from fats to carbohydrates.

Anorectal manometry and suction biopsy were carried out on 47 children with constipation or soiling, or both. Patients were divided into two groups. Group 1 (37 patients): functional faecal retention, group 2 (10 patients): functional faecal soiling without retention. Ganglion cells or normal acetylcholinesterase staining, or both, was demonstrated in all cases. Normal inhibition of internal sphincter could be achieved by rectal distension in all except 2 children with severe constipation. Resting sphincteric pressures, pressure responses, and conscious rectal sensitivity thresholds were similar in groups 1 and 2, but were increased compared with controls. In group 1 alone, the critical volume increased parallel with conscious rectal sensitivity threshold. Since the complete relaxation of internal sphincter occurs before conscious rectal sensation arises in children with soiling without retention, this may be an important factor, at least in some of the soilers.

The metabolic and hormonal effect of Escherichia coli endotoxin injected intraperitoneally was studied in fed and starved rabbits aged 6-9 days. Fed rabbits responded to endotoxin with fever, starved animals became hypothermic. Endotoxin caused a transient rise in blood glucose in both groups which was associated with a rise in plasma insulin concentration. Blood glycerol levels fell only in starved rabbits, and hydroxybutyrate concentration in both groups following endotoxin treatment. No change in blood pyruvate, lactate, alanine, or acetoacetate level was observed in either group.

Simple, incentive based behaviour modification, with or without a modest programme of psychotherapy involving outpatient visits every four to six weeks, seems to be associated with a useful cure rate in children with lower bowel function disorders. Appreciable social disadvantage seems to be the most important factor mitigating against a successful outcome, associated with non-compliance with treatment. Failure to respond to treatment was associated with important psychological problems. These were more common in the socially disadvantaged groups. Children from satisfactory social backgrounds who have lower bowl disturbances can be effectively treated by fairly simple programmes. More elaborate and expensive strategies should be reserved for those whose psychosocial circumstances make it possible to predict a less satisfactory outcome.

Phage H, thought to be specific for Pasteurella pestis, was shown to plate efficiently on F(-) strains of Escherichia coli but not on F(+), F', or Hfr strains. The phage was adsorbed rapidly to F(-) strains but was not adsorbed to strains carrying F. Comparison with seven other reported female-specific phages showed that, although phage H was similar to the other phages in some characteristics, the exceptionally low efficiency of plating (<10(-9)) on F-containing cells makes phage H a particularly useful female-specific phage.

Molnar, Dorothy M. (U.S. Army Chemical Corps, Fort Detrick, Frederick, Md.). Separation of the toxin of Bacillus cereus into two components and nonidentity of the toxin with phospholipase. J. Bacteriol. 84:147-153. 1962-Bacillus cereus produced toxin in a Casamino acids medium without added serum or other protein. The toxin was separated into two components by adsorption on columns of calcium phosphate gel followed by elution with phosphate buffer (pH 7.5). The component eluted first has been called factor I and the component eluted later factor II. When tested alone each component was relatively nontoxic, but when combined they formed a toxic mixture as evidenced by skin reactions in guinea pigs and tests for lethal effects in mice. The phospholipase activity, determined by the egg-yolk reaction, was found in the fraction containing factor I. However, using columns of alumina-C(gamma) gel the phospholipase activity was found in the fraction containing factor II. This suggests that the phospholipase is not the same chemical entity as either factor I or II. The following are further evidence for the non-identity of the toxin and phospholipase: (i) differential precipitation of the two activities by (NH(4))(2)SO(4); (ii) differential neutralization by various antisera; and (iii) differential inhibition with ethanol.

When either the F' lac or the F'Cm plasmid was transferred from Escherichia coli into Pasteurella pseudotuberculosis, the P. pseudotuberculosis (F') strains isolated formed plaques with both ribonucleic acid (RNA)-containing and deoxyribonucleic acid-containing male-specific phages. In contrast, strains of P. pestis harboring E. coli (F') plasmids did not form plaques with male-specific phages, although such strains permitted limited multiplication of phage MS2. The adsorption and burst size of MS2 were approximately the same in both species of Pasteurella, but the per cent of adsorbed MS2 that produced infective centers was much lower in P. pestis than it was in P. pseudotuberculosis. By use of a sib-selection technique of P. pestis (F') cells, we isolated a single clone that could form MS2 plaques. (32)P-labeled MS2 adsorbed equally to and its RNA penetrated equally into both the typical MS2-nonpermissive P. pestis cells and the MS2-permissive P. pestis cells. No host modification occurred after growth of MS2 in Pasteurella. Our data suggest that typical strains of P. pestis inhibit the intracellular development of phage MS2.

Bacteriophage P1 CM can convert Pasteurella pestis or P. pseudotuberculosis to chloramphenicol resistance and phage restriction, but no viable phage was induced from converted Pasteurella strains.