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Understanding the associations and possible mechanisms between Cardiorespiratory Fitness (CRF) and residential location is an important focus of public health research. This is a cross-sectional study carried out with 2250 students (6-17 years), from southern Brazil. In addition to age, sex, and body size measurements, we also recorded hemoglobin and platelet count measurements using venous blood samples (10 ml). The CRF was measured using the 6-minute run/walk test, with predictors explored via allometry. Results identified a novel and independent association between the hemoglobin-to-platelet count ratio and children's CRF, after controlling for confounders. We also provide evidence of a possible mechanism for this association, having identified reduced measures of hemoglobin and increased platelet counts observed in children living in urban (vs rural) areas. These results suggest the need for more effective public health practices and policies addressing the built enviroment´s health effects in Brazil and potentially other congested ciries.

Aim: To verify the association between ideal sleep time and physical literacy components while also considering multiple mediators, such as quality of life and obesity, using a sample of adolescents., Methods: This cross-sectional study consisted of 470 adolescents aged 11-17 years from southern Brazil. Sleep time, health-related quality of life, and physical literacy components (i.e., physical education enjoyment, sports participation, sedentary behavior, moderate to vigorous physical activity, sex, and age) were evaluated through self-reported questionnaires. In addition, body mass index (BMI), and waist circumference were determined. The theoretical/statistical support of the structural equation model was evaluated according to fit parameters and strength of association., Results: A direct association was observed between more sleep time and lower levels of obesity. The obesity indicators also had a negative association with HqOL, and HqOL had a positive association with physical literacy. The indirect associations indicated that the ideal sleep time was positively associated with HqOL and physical literacy components, considering the negative mediation effect of obesity. The model explains physical literacy in 31% of the variance (R = 0.31)., Conclusion: There was an indirect association between ideal sleep duration and quality of life and between both variables with physical literacy. These relationships occur even considering the negative influence of obesity. Therefore, a child who sleeps adequately has a higher likelihood of being physically active, regardless of obesity, potentially enhancing overall quality of life across various domains., (© 2024. The Author(s).)

To verify the role of the combination of fitness and fatness in the relationship between physical activity (PA) and cardiometabolic risk in children and adolescents. This is a cross-sectional study performed with 2786 children and adolescents (6 to 17 years). Fitness was determined by the cardiorespiratory fitness (CRF) six-minute walking and running test. Waist circumference (WC) was considered a fatness indicator. A selfreported questionnaire was used to determine PA practice, whereas the clustered cardiometabolic risk score (cMetS) was calculated by summing z-scores of triglycerides, total cholesterol/HDL-C ratio, systolic blood pressure, glucose, and WC. Considering the combination of CRF (fitness) and WC (fatness), the following phenotypes were created: Fit/Unfat, Fit/Fat, Unfit/Unfat and Unfit/Fat. Moderation analyses were tested using linear regression models. Significant interactions were found between PA and Unfit/Fat category (β = -0.001; p = 0.001) only for adolescents. The interaction observed in the Unfit/Fat phenotype indicated that adolescents who practise PA for 330 minutes per week presented lower cMetS compared to those who do not practise or practise for 60 minutes respectively. The combination of fitness and fatness moderates the relationship between PA and cardiometabolic risk, suggesting that adolescents, particularly those who are less fit and present high adiposity, should be encouraged to engage in regular PA to improve their metabolic health., Competing Interests: The authors declare no conflict of interest., (Copyright © Biology of Sport 2024.)

Purpose: The aim of this study was to examine the interaction between screen time and cardiorespiratory fitness (CRF) in their longitudinal association with waist circumference (WC) during a follow-up of 3 years from childhood to adolescence., Methods: Observational 3-year longitudinal study with 401 students (224 females), seven to 15 years of age at baseline. The CRF was evaluated by estimating peak oxygen uptake (VO 2peak ) from an indirect field-based test and body mass index. Screen time was assessed using self-reported questionnaires. Moderation analyses were tested using a multiple linear regression model with adjustments for sex, age, puberty stage, and ethnicity., Results: A statistically significant interaction term was observed (B = -0.0003; 95% CI: -0.007; -0.0001). Since screen time was contextualized as the independent variable, the results show that relationship between screen time and WC varies across different CRF levels., Conclusion: The findings suggest that higher CRF can attenuate the harmful association that increased sedentary behavior might have on abdominal adiposity., (© 2023. The Author(s).)

Background: We examined the moderating influence of home location and school type across time on cardiometabolic risk and active school commuting over 5 years in a sample of children from southern Brazil. Methods: We recruited a sample of children ( n  = 154; baseline age = 9.6 ± 1.5 years old; 56.8% female) who were followed for 5 years from 2011/2012 to 2016/2017. We collected home location, school type, and school commute data using self-report methods and collected cardiometabolic risk measures to calculate a cardiometabolic composite risk score (cMetSyn). General and generalized linear mixed effects models were employed to examine the moderating influence of home location and school type across time on cardiometabolic risk and active school commuting. Results: We found a significant three-way home location × school type × time interaction on cMetSyn scores ( b  = 0.62, 95% confidence interval [CI]: 0.13-1.12, p  = 0.014), indicating that children who were living within rural areas and enrolled in state schools during 2016/2017 had higher cardiometabolic risk compared with children enrolled in municipal schools and living in urban areas at the end of the study. Additionally, we found that children living in rural areas had an 86% lower rate of active school commuting compared with students living in urban areas (rate ratio = 0.14, 95% CI: 0.07-0.32, p  < 0.001). Conclusions: The results suggest that Brazilian children enrolled in state schools and living in rural areas had higher cardiometabolic risk scores at the end of the study and that southern Brazilian children residing in rural areas had a much lower rate of actively commuting to school.

Background: The behavior of anthropometrics and the relationship with genetic factors through a long-term perspective should be better explored. This study aims to verify the odds of maintaining the nutritional status classification after three years, according to the rs9939609 polymorphism (FTO gene)., Methods: It was a retrospective longitudinal study with 355 schoolchildren (7-17 years). Body mass index, body-fat percentage (BF%), and waist circumference (WC) were measured at baseline and follow-up. The FTO gene was evaluated from blood collection and genotyping performed by real-time polymerase chain reaction. Odds ratios and 95% confidence intervals were calculated., Results: For those homozygous with the A allele, the odds of being at less favorable classification at follow-up were 2.29 (1.24; 4.22) and 4.05 (2.08; 7.86) times higher than expected for BF% and WC, respectively, whereas the odds of being in the more favorable classification at follow-up were 0.34 (0.12; 0.93) and 0.11 (0.01; 0.78) for BF% and WC, respectively. The odds of being at less favorable classification were higher for AA carriers with less favorable classification at baseline for BF% and WC compared to AT and TT carriers., Conclusions: Schoolchildren with a genetic predisposition to obesity and unfavorable anthropometric profile at baseline had more chances of maintaining their nutritional status after three years of follow-up., (© 2023. The Author(s).)

Objective: The present study aims to verify the odds of remaining with the clustering of 3 or more, 4 or more, and 5 or more risk factors across a 2-year time span., Methods: Observational longitudinal study that included 358 children and adolescents (10.96 ± 2.28 years of age at baseline). Cardiorespiratory fitness, glucose, systolic blood pressure, total cholesterol/high-density lipoprotein cholesterol ratio, triglycerides, and waist circumference were assessed. The number of children in whom the risk factors were not independently distributed was analyzed. Odds ratios of presenting n risk factors clustered at follow-up according to the number of risk factors observed at baseline were calculated., Results: More participants than expected were found presenting clustering of 4 or more and 5 or more risk factors at both baseline (11.7% and 5.6%, respectively) and follow-up (9.5% and 5.6%, respectively). The odds ratios calculated demonstrated that the odds of presenting the same number of risk factors clustered or more at follow-up increased according to the number of risk factors clustered at baseline., Conclusion: The higher the number of risk factors a child had at baseline, the higher the odds of presenting the same number of risk factors or more after two years of follow-up., Supplementary Information: The online version contains supplementary material available at 10.1007/s40200-022-01174-1., Competing Interests: Competing interestsThe authors state no conflict of interest., (© The Author(s), under exclusive licence to Tehran University of Medical Sciences 2022. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

The aim of the present study was to verify whether the amount of sleep duration, screen time, and physical activity moderate the relationship between FTO rs9939609 polymorphism and waist circumference (WC) in children and adolescents. This is a cross-sectional study conducted with 1338 children and adolescents, aged between 6 and 17 years. Lifestyle habits were assessed through self-reported questionnaire. WC was measured on the narrowest part of the trunk between the last rib and the iliac crest. FTO rs9939609 polymorphism was genotyped by real time polymerase chain reaction. The PROCESS macro for the SPSS was used for moderation analyses, through multiple linear regression models. Results indicated significant interactions were found between sleep duration and screen time X FTO rs9939609, showing that these lifestyle behaviours are moderators in the relationship between a genetic predisposition for obesity and higher WC. For physical activity, there was no significant interaction. Therefore, sleeping more than 564 min a day (i.e. 9.4 h) and spending no more than 233 min in front of screen may counteract the genetic predisposition to obesity in children and adolescents. Highlights A healthy lifestyle may counteract the genetic predisposition to central obesity;Children and adolescents should sleep more than approximately 9 h (564 min) per day and spend less than approximately 4 h (233 min) per day in front of screens in order to counteract the genetic predisposition to central obesity conferred by the FTO gene variant.It is fundamental to promote actions for the adoption of a healthy lifestyle, including the importance of presenting adequate sleep habits and low screen time for a better cardiometabolic health and reduction of obesity.

Purpose: To identify whether physical fitness (PF) components play a moderating role in the relationship between TV time and adiposity levels., Design: Cross-sectional study., Setting: Few studies have examined if different PF levels modify the association between TV time and adiposity in adolescents. Studies often focus on the isolated relationships between obesity and TV time, or obesity and PF levels., Subjects: 1071 adolescents (617 girls), aged 12 to 17 years., Measures: Cardiorespiratory fitness (CRF), abdominal muscular endurance, and lower limb strength were evaluated using the protocols of the Projeto Esporte Brasil fitness testing battery. TV time was obtained using a self-reported questionnaire. Body mass index (BMI) and waist circumference (WC) were also assessed. Moderation analyses were conducted through multiple linear regression models with the following associations tested in different models: PF components, TV time, and interaction (PF component x TV time) with adiposity parameters (BMI and WC)., Results: A significant interaction term was found for CRF and TV time in the association with both WC (β: -.005; 95% CI: -.009; -.001; P = .012) and BMI (β: -.002; 95% CI: -.004; -.001; P = .009)., Conclusion: CRF moderates the relationship between TV time and adiposity measures in this cross-sectional analysis. These data support strategies looking at increasing physical activity levels to improve CRF and avoid the development of excess abdominal obesity and excess weight.

The purpose of the current study was to identify the most appropriate "body shape" associated with six athletic performance (AP) tests, using three-dimensional allometry (height (HT), body mass (M), and waist circumference (WC)), in a sample of Brazilian children and adolescents. The sample consisted of 11018 Brazilian children/adolescents (5147 boys) aged 7-17 years. The 6 AP tests were, a 20 m sprint test, an agility test, a 6/9 minute walk/run endurance test, an upper body strength test, an abdominal muscular endurance test, and a lower limb strength test. The "three-dimensional" allometric model was, A P = a ⋅ M k 1 ⋅ H T k 2 ⋅ W C k 3 . Results indicated that two of the three body-size dimensions (HT and WC) were consistently associated with all six athletic performance tests. These were a positive HT exponent/term together with a negative WC exponent/term, confirming that being taller benefited all six performance tests but excess WC was always detrimental. The contribution of M depended on whether the athletic performance required the children/adolescent to perform the exercise/test in a "weight-baring" protocol, i.e. having to perform the test carrying their own body weight or not. In conclusion, three-dimensional allometry provides new insights into what constitutes the "ideal" athletic shape associated with children/adolescents.

Background: A better understanding of how cardiorespiratory fitness (CRF) and adiposity interact to associate with arterial blood pressure over time remains inconclusive. Thus, the aim of the present study was to examine whether changes in CRF moderates the association between body fat percentage (BF%) and arterial blood pressure in children and adolescents., Methods: This is an observational longitudinal study with 407 children and adolescents aged 8-17 years followed-up for three years from a city in Southern Brazil. Participants were evaluated in 2011 and 2014. CRF was measured by validated field-based tests following the Projeto Esporte Brazil protocols and peak oxygen uptake (VO 2peak ) was estimated. BF% was determined by the measures of tricipital and subscapular skinfolds using equations according to sex. Systolic and diastolic blood pressure (SBP, DBP) were measured with a sphygmomanometer according to standard procedures. Moderation analyses included multiple linear regression models adjusted for sex, age, pubertal status, height, socioeconomic level, skin color, and the arterial blood pressure variable itself at baseline., Results: It was observed a significant inverse association between VO 2peak at baseline with SBP (β = - 0.646 CI95% = - 0.976  - 0.316) and DBP (β = - 0.649 CI95% = - 0.923  - 0.375) at follow-up and a positive association between BF% at baseline with SBP (β = 0.274; CI95% = 0.094 0.455) and DBP (β = 0.301; CI95% = 0.150 0.453) at follow-up. In addition, results indicated a significant interaction term between changes in VO 2peak and BF% at baseline with both SBP (p = 0.034) and DBP at follow-up (p = 0.011), indicating that an increase of at least 0.35 mL/kg/min and 1.78 mL/kg/min in VO 2peak attenuated the positive relationship between BF% with SBP and DBP., Conclusion: CRF moderates the relationship between BF% and SBP and DBP in children and adolescents., (© 2022. The Author(s).)

Background: Genetic factors along with inadequate lifestyle habits are associated with the development of cardiometabolic alterations. Thus, the present study aimed to examine the role of sedentary behavior on the relationship between rs9939609 polymorphism (fat mass and obesity-associated gene-FTO) and cardiometabolic risk score according to cardiorespiratory fitness (CRF) levels in children and adolescents., Methods: A cross-sectional study with 1215 children and adolescents (692 girls), aged between 6 and 17 years. Screen time as a marker of sedentary behavior was evaluated through a self-reported questionnaire and CRF was estimated using the 6-min walking and running test. The genotyping of the FTO rs9939609 polymorphism was performed using a real-time polymerase chain reaction. Clustered cardiometabolic risk score (cMetS) was calculated by summing z-scores of total cholesterol/high-density lipoprotein cholesterol ratio, triglycerides, glucose, systolic blood pressure, and waist circumference, and dividing it by five. Moderation analyses were tested using multiple linear regression models., Results: The coefficient of the interaction term of FTO (rs9939609) and screen time indicated that screen time was a significant moderator on the relationship between FTO rs9939609 polymorphism and cMetS (p = 0.047) in children and adolescents classified with low CRF (β = 0.001; 95% CI = 0.001; 0.002). It was observed a significant association between genotype risk (AA) of FTO polymorphism and cMetS, in participants that spent more than 378 min a day in front of screen-based devices (β = 0.203; 95% CI = 0.000; 0.405). No interaction term was found for those with high CRF., Conclusions: High sedentary behavior seems to influence the relationship between genetic predisposition to obesity and cardiometabolic risk factors in children and adolescents with low CRF., (© 2022. The Author(s).)

Background: A healthy lifestyle should be adopted by young people to maintain cardiometabolic health., Aim: To verify the prevalence and the integrated role of lifestyle habits in cardiometabolic risk factors according to sex in adolescents., Subjects and Methods: Cross-sectional study developed with 1502 adolescents, aged 10-17 years. Lifestyle habits included physical activity, screen time and sleep duration evaluated through a questionnaire. Cardiometabolic risk score (CMRS) was calculated by summing z -scores, divided by 6. For statistical analyses, multivariable binary and multinomial logistic regression models were used., Results: 80.7% of the boys classified with adverse CMRS presented physical inactivity, compared to normal CMRS. In girls, 42.6% showed inadequate sleep compared to normal CMRS. Boys classified as inactive showed higher odds for obesity, as well as altered triglycerides (TGs), and systolic blood pressure, risk for cardiorespiratory fitness (CRF), high waist circumference, and CMRS, compared to the active. A prolonged screen time increased the odds for altered glucose and decreased the odds for altered TGs. In girls, inadequate sleep duration presented higher odds for overweight, obesity, risk for CRF, and high CMRS, compared to adequate sleep., Conclusion: Physical activity for boys and sleep duration for girls are important to maintain healthy metabolic health amongst youth.

Background: Cardiorespiratory fitness (CRF) is considered a beneficial effect of physical activity (PA). PA and excessive screen time have implications for cardiometabolic risk., Objective: To verify the association between screen time and CRF grouped by cardiometabolic risk factors., Subjects and Methods: Cross-sectional study evaluated 1,253 schoolchildren (54.2% girls) aged seven to 17 years from southern Brazil. The outcomes were body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP), and diastolic (DBP), glucose, and lipid profile. Exposure was a combined variable of self-reported screen time (television, video game, computer) and CRF., Results: The main result is that CRF had a more consistent association with anthropometric factors than with metabolic variables. Low CRF students, regardless of screen time, showed a 15% increase in the risk of elevated WC ( p  < 0.001) and a 24% (<2 h screen time) and 19% (≥2 h) higher risk of overweight ( p  < 0.001). Second, the increase in SBP was associated with a combination of the two risk factors, ≥2 h screen time/low CRF was associated with a 7% increase in elevated SBP ( p  = 0.025)., Conclusion: Low CRF was a risk factor for elevated BMI and WC, regardless of screen time. High screen time and low CRF were associated with higher SBP values.

Background: Given the important repercussions that sociodemographic factors can have on physical activity, especially in the field of leisure, and cardiometabolic risk, it seems relevant to analyze the implications of these variables on the relationship between physical activity in leisure time (LTPA) and cardiometabolic risk. In this sense, the present study aims to verify the moderating role of biologic and socioeconomic factors in the relationship between LTPA and cardiometabolic risk in adolescents in southern Brazil., Methods: Cross-sectional study that included 1596 adolescents selected at random (58.2% girls), aged between 10 and 17 years. LTPA, biological and socioeconomic factors were assessed using a self-reported questionnaire and the cardiometabolic risk score (total cholesterol/HDL-c ratio, triglycerides, fasting glucose, systolic blood pressure, and waist circumference, considering the participant's age and sex) was included as an outcome. Associations and moderations were tested by multiple linear regression models., Results: It was observed a positive interaction of LTPA and sex (p = 0.048) and LTPA and school system (p = 0.037), and negative interaction of LTPA and skin color (p = 0.040), indicating that these factors were moderators in the relationship between LTPA and clustered cardiometabolic risk score (cMetS) in adolescents. A reduction in cardiometabolic risk was observed according to the increase in weekly minutes of LTPA among boys, non-white adolescents, and students from municipal schools., Conclusions: The association between LTPA and cardiometabolic risk was moderated by sex, skin color, and school system in adolescents from southern Brazil., (© 2021. The Author(s).)

Background: The increased incidence of cardiometabolic risk factors has become a public health issue, especially in childhood and adolescence. Thus, early identification is essential to avoid or reduce future complications in adulthood. In this sense, the present study aimed to verify the influence of cardiorespiratory fitness (CRF) as a moderator in the association between neck circumference (NC) and cardiometabolic risk in children and adolescents., Methods: Cross-sectional study that included 2418 randomly selected children and adolescents (52.5% girls), aged 6 to 17 years old. Anthropometric measurements, such as NC and body mass index (BMI), and CRF was measured by the six-minute running/walking test, as well as cardiometabolic risk (systolic blood pressure, glucose, HDL-C, and triglycerides), were assessed., Results: For all age groups, NC showed a negative relationship with CRF. A significant interaction term was found for CRF x NC with cardiometabolic risk for children (6 to 9 years old), early adolescents (10 to 12 years old), and middle adolescents (13 to 17 years old). It was found that children who accomplished more than 1092.49 m in CRF test were protected against cardiometabolic risk when considering NC. In adolescents, protection against cardiometabolic risk was found when the CRF test was completed above 1424.14 m and 1471.87 m (early and middle stage, respectively)., Conclusions: CRF is inversely associated with NC and acts as a moderator in the relationship between NC and cardiometabolic risk in children and adolescents. Therefore, this detrimental health impact linked to fatness might be attenuated by improving CRF levels.

Background: The aim of this study was to verify the moderator role of physical fitness in the relationship between adiposity and cardiometabolic risk factors in normal weight and overweight/obese children and adolescents., Methods: Cross-sectional study comprising 2482 children and adolescents, aged 7-17 years. Physical fitness was evaluated according the procedures of Projeto Esporte Brazil, and waist circumference (WC) with an inelastic tape. Cardiometabolic risk score was defined by the z-score sum of glucose, total cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol. Moderation analysis was done through linear regression models., Results: Significant interaction term for cardiorespiratory fitness (CRF)×WC with cardiometabolic risk factors (P<0.001), as well as for lower limbs strength (LLS)×WC (P<0.001) and agility × WC (P=0.01) in normal weight girls. For normal weight boys it was found a significant interaction term for CRF×WC with cardiometabolic risk factor (P=0.007), and also for agility × WC (P=0.003), while overweight/obese boys showed a significant interaction term only for agility × WC with cardiometabolic risk factor (P=0.001)., Conclusions: CRF, LLS and agility are moderators in the relationship between WC and cardiometabolic risk factors in normal weight girls, while CRF and agility were moderators for normal weight boys and only agility for overweight/obese boys.

Objectives: The combination of sleep duration, television (TV) time and body mass index (BMI) may be related to the alteration of cardiometabolic risk. However, there are few studies that use these variables grouped, and showing the moderating role of age. This study aimed to verify if the combination of sleep duration, TV time and BMI is associated with cardiometabolic risk and the moderating role of age in this relationship in youth., Methods: Cross-sectional study conducted with 1411 adolescents (611 male), aged 10-17 years. Sleep duration, TV time and BMI were assessed and grouped into eight categories. Cardiometabolic risk was assessed by a continuous metabolic risk score, including the following variables: low HDL-cholesterol, elevated triglycerides, dysglycemia, high systolic blood pressure, high waist circumference and low cardiorespiratory fitness. Generalized linear models were used to test moderation of age in the relationship between the eight categories of sleep duration/television time/BMI with cardiometabolic risk., Results: Cardiometabolic risk factor showed association with all overweight or obesity independent of sleep time and TV time. Age moderated the relationship between sleep duration/television time/BMI with cardiometabolic risk. This association was stronger in younger adolescents (11 and 13 years), indicating that individuals with inadequate sleep, prolonged TV time and overweight/obesity present higher cardiometabolic risk values when compared to 15-year-old adolescents., Conclusion: Overweight/obesity, independently of sleep duration and TV time, is the main risk factor for cardiometabolic disorders in adolescence. When moderated by age, younger adolescents that presented the combination of risk factors had higher cardiometabolic risk., (© 2020 Walter de Gruyter GmbH, Berlin/Boston.)

Objective: To verify the association between sleep duration and television time with cardiometabolic risk and the moderating role of age, gender, and skin color/ethnicity in this relationship among adolescents., Methods: Cross-sectional study with 1411 adolescents (800 girls) aged 10 to 17 years. Television time, sleep duration, age, gender, and skin color/ethnicity were obtained by self-reported questionnaire. Cardiometabolic risk was evaluated using the continuous metabolic risk score, by the sum of the standard z-score values for each risk factor: high-density lipoprotein cholesterol, triglycerides, glycemia, cardiorespiratory fitness, systolic blood pressure, and waist circumference. Generalized linear regression models were used., Results: There was an association between television time and cardiometabolic risk (β, 0.002; 95% CI, 0.001; 0.003). Short sleep duration (β, 0.422; 95% CI, 0.012; 0.833) was positively associated with cardiometabolic risk. Additionally, age moderated the relationship between television time and cardiometabolic risk (β, - 0.009; 95% CI, - 0.002; - 0.001), suggesting that this relationship was stronger at ages 11 and 13 years (β, 0.004; 95% CI, 0.001; 0.006) compared to 13 to 15 years (β, 0.002; 95% CI, 0.001; 0.004). No association was found in older adolescents (β, 0.001; 95% CI, - 0.002; 0.002)., Conclusions: Television time and sleep duration are associated with cardiometabolic risk; adolescents with short sleep have higher cardiometabolic risk. In addition, age plays a moderating role in the relationship between TV time and cardiometabolic risk, indicating that in younger adolescents the relationship is stronger compared to older ones.

Background: Little has been studied on heart rate and its relationship with metabolic disorders., Objective: To identify possible association between heart rate (HR) and metabolic disorders in children and adolescents., Methods: This cross-sectional study evaluated 2.098 subjects, aged between 7 and 17 years. The variables evaluated were: HR, systolic (SBP) and diastolic blood pressure (DBP), pulse pressure (PP), double-product (DP), myocardial oxygen consumption (mVO2), lipids, glucose and uric acid levels, body mass index (BMI) and waist circumference (WC). The values of HR at rest and effort were divided into quartiles. The association between continuous values of HR and cardiometabolic indicators was tested by linear regression., Results: LDL cholesterol presented a significantly higher mean (p = 0.003) in schoolchildren with resting HR greater or equal to 91 bpm, compared to students with less than 75 bpm. Compared with the quartiles of effort HR, SBP, DBP, glucose and uric acid presented high values when HR was greater or equal than 185 bpm. SBP, glucose and HDL cholesterol demonstrated a significant association with resting HR. Uric acid was observed as a predictor of increased effort HR., Conclusion: Schoolchildren with a higher resting HR have higher mean of LDL cholesterol. For effort HR, there was an increase in blood pressure, glucose and uric acid levels. Uric acid has been shown to be a predictor of elevated effort HR.

Objective: To evaluate the possible association between hyperuricemia and cardiorespiratory fitness levels/nutritional profile, grouped into a single variable, in schoolchildren., Method: Cross-sectional study of 2335 students from Elementary schools, aged 7-17 years of both genders, stratified by conglomerates of a municipality in Southern Brazil. Body mass index (BMI) was calculated and cardiorespiratory fitness (CRF) was assessed by the 6-minute run/walk test. The BMI and CRF were grouped into a single variable, considering: (1) low and normal weight/fit; (2) low and normal weight/unfit; (3) overweight-obesity/fit; (4) overweight-obesity/unfit. The Poisson regression (prevalence ratio, PR) was used for the association between hyperuricemia and BMI/CRF ratio with 95% confidence intervals and differences were considered significant when p<0.05., Results: There is an association, although subtle, between the presence of hyperuricemia with low levels of CRF and the presence of excess weight, when grouped into a single variable. Boys and girls with this condition have higher prevalence of hyperuricemia (PR: 1.07; p=0.007 for boys; PR: 1.10; p<0.001 for girls)., Conclusion: Together, excess weight and low levels of cardiorespiratory fitness are associated with the presence of hyperuricemia in schoolchildren., (Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.)

The anaerobic, but aerotolerant Propionibacterium freudenreichii sp. shermanii contains a single superoxide dismutase [EC 1.15.1.1.] exhibiting comparable activity with iron or manganese as metal cofactor. The formation of superoxide dismutase is not depending on the supplementation of iron or manganese to the culture medium. Even in the absence of these metals the protein is built in comparable amounts. Bacteria grown in the absence of iron and manganese synthesize a superoxide dismutase with very low activity which had incorporated copper. If the medium was also depleted of copper, cobalt was incorporated, leading to an enzymically inactive form. In the absence of cobalt an enzymically inactive superoxide dismutase was built with unknown metal contents. Upon aeration the amount of superoxide dismutase activity increased continuously up to 9 h, due to a de novo synthesis of the protein. This superoxide dismutase had incorporated iron into the active centre. The superoxide dismutase of Propionibacterium shermanii is able to form a much wider variety of complexes with trace metal ions in vivo than previously recognized, leading to the hypothesis that the original function of these proteins was the binding of cytoplasmic trace metals present in excess.

Propionibacterium shermanii contains a single constitutive superoxide dismutase (SOD) which is active with either iron or manganese incorporated in the same protein moiety. Copper and cobalt can also be incorporated by the bacteria in the active center of the SOD under conditions of metal deficiency, but in this case the enzyme is enzymatically inactive. In contrast to other bacterial SODs, the Fe-SOD of P. shermanii remains highly resistant to inactivation by hydrogen peroxide, as does Mn-SOD. Both SOD types cannot be distinguished by their inactivation patterns. Incubation with hydrogen peroxide results in a concentration- and time-dependent decrease in tryptophan fluorescence, independent of the metal present in the active center. Moreover, the Fe-SOD shows a time-dependent decrease in spin concentration after addition of hydrogen peroxide, which reflects alterations in the environment of the metal rather than a reduction of Fe3+ to Fe2+. No obvious correlations exist, however, between these effects and the enzymatic activity of the enzyme. The resistance of the SODs from P. shermanii to inactivation by hydrogen peroxide seems to be caused by the fact that a tryptophan residue near the metal-chelating histidine-75--which is present in all Fe-SODs being rapidly inactivated by this agent--is exchanged for valine.

Propionibacterium shermanii, an aerotolerant anaerobic bacterium, has already been shown to incorporate, depending on the metal supplementation to the medium, either iron or manganese or copper into the same superoxide dismutase protein. The in vivo incorporation of cobalt in the same superoxide dismutase was obtained in an iron-, manganese- and copper-depleted medium. The protein was isolated and characterized by NMR which offers the possibility to identify the amino acid residues at the active site exploiting isotropically shifted proton resonance.

Propionibacterium shermanii, an aerotolerant anaerobe, produces an iron-containing or a manganese-containing superoxide dismutase, depending on the metal supplied in the culture medium [Meier, B., Barra, D., Bossa, F., Calabrese, L. & Rotilio, G. (1982) J. Biol. Chem. 257, 13977-13980]. In this study, we demonstrate in vivo incorporation of copper into an active superoxide-dismutase protein when iron and manganese are absent from the growth medium. Superoxide dismutases containing either iron, manganese or copper were isolated from P. shermanii, their complete amino acid sequences were determined and the identity of their protein moieties was established. The polypeptide chain is made up of 201 amino acid residues, corresponding to a molecular mass of 22.6 kDa. From sedimentation equilibrium experiments, the native protein shows a molecular mass of approximately 86 kDa and therefore consists of four identical subunits. The primary structure was compared with the structure of other Fe-superoxide dismutases and Mn-superoxide dismutases, in particular those possessing a strict metal cofactor specificity.