Years Of Age In Boys Research Articles

Age- and Sex-Dynamic Fluctuations and Reference Intervals for Alkaline Phosphatase Among the Spanish Population.

Interpretation of alkaline phosphatase (ALP) activity is essential for the diagnosis of certain diseases. ALP changes during life and may vary between different populations. To establish reference intervals (RIs) and percentile charts for ALP activity in the Spanish population through a multicentric observational study and to compare the RIs to those defined in other countries. A total of 662 350 ALP measurements from individuals ages 0 to 99 years from 9 Spanish tertiary care centers collected between 2020 and 2022 were analyzed. This study is the largest published in the literature to date. Continuous percentile charts for ALP according to sex and age were established which can be used as RIs. Higher levels are reached during the first weeks of life. In puberty, a differential evolution is observed in both sexes, reaching a peak at 10 to 13 years of age in boys and remaining stable in girls at this age. Significant differences were also observed in adults, higher in men between ages 20 and 49 years and between ages 50 and 79 years in women, as reported in some countries. ALP activity follows an age- and sex-dependent fluctuation with geographic differences. It is important to have appropriate reference values for each population in order to allow for a correct diagnostic interpretation and early diagnosis of diseases related to ALP abnormalities.

Further progress of the etiology,diagnosis and treatment of peripheral precocious puberty

Peripheral precocious puberty(PPP),also known as puberty independent from hypothalamic-pituitary axis activation,is stimulated by hormones from other sources, with only partial sexual characteristics development but without mature sexual function. The secondary sexual characteristics development occurs before 7.5 years of age in girls and before 9 years of age in boys. Clinical manifestations are diverse, and PPP has varied etiology including congenital adrenal hyperplasia, McCune-Albright syndrome, ovarian cyst, adrenal tumor, ovarian tumor, testicular tumor, human chorionic gonadotropin producing tumor, familial male precocious puberty, aromatase excess syndrome, and environmental estrogen. Early identification of etiology, accurate differential diagnosis and prenatal gene screening play a significant role in the prevention, diagnosis and treatment of the disease.

The Associations of Birthweight for Gestational Age Status with Its Differential 0-2 Year Growth Trajectory and Blood Pressure at Two Years of Age in Chinese Boys and Girls.

The first 1000 days of life represents a critical period for lifelong metabolic health. This study prospectively examined the contrasts between the growth trajectories of large, small, and appropriate sizes for gestational age (LGA, SGA, and AGA) term-born infants in their first two years, and their blood pressure at two years. In 2012-2013, 806 Chinese mother-newborn dyads were enrolled in the Shanghai Obesity and Allergy Birth Cohort Study. Repeated anthropometric measures were obtained at age 42 days, and at 3, 6, 9, 12, 18 and 24 months. Systolic and diastolic blood pressure (SBP, DBP) were measured at two years of age. Linear random effect models were employed to evaluate growth trajectory differences between LGA, SGA, and AGA infants. Of the study infants, 12.4% were LGA and 4.0% SGA. Length, weight, and weight-for-length z-score (ZWFL) were all consistently higher in LGA infants and lower in SGA infants than AGA infants. SGA infants had a higher ZWFL (0.11 unit/month; 95% CI: 0.04, 0.19) and a higher BMI (0.19; 95% CI: 0.09, 0.28 kg/m2 per month) growth velocity at age 0-6 months, relative to AGA infants. SGA was associated with 6.4 (0.4-12.4) mmHg higher SBP, and LGA was associated with 2.9 (95% CI -5.2, -0.5) mmHg lower DBP at two years of age in boys, however, not in girls. In conclusion, in this prospective birth cohort with repeated anthropometric measures and BP at two years of age, LGA, SGA, and AGA term-born infants manifested differential patterns of weight growth trajectory and BP, providing new insight into developmental origins of cardiometabolic health.

Precocious puberty: experience in the Pediatric Endocrinology Unit at the Children's Hospital in Rabat

Introductionla puberté précoce est définie par le développement des caractères sexuels avant l´âge de 8 ans chez la fille et de 9 ans chez le garçon. L´objectif de notre étude était de décrire le profil clinique, paraclinique et étiologique de la puberté précoce.Méthodesil s´agit d´une étude descriptive rétrospective s´étalant de 1999 à 2017 à l´unité d´endocrinologie pédiatrique à l´Hôpital d´Enfant de Rabat.Résultatsquatre-vingt-dix-neuf (99) enfants ont été inclus. L´âge moyen des filles était de 4,25 ± 2,6 ans, celui des garçons était de 3,6 ans ± 1,8. Nous avons noté une prédominance féminine dans 90% (90 filles). Les signes révélateurs chez la fille étaient dominés par le développement mammaire (77,77%). Chez le garçon, le motif de consultation le plus fréquent était la pilosité pubienne (70%). Sur le plan biologique, dans les pubertés précoces centrales, le taux moyen du pic de LH après stimulation par GnRH était élevé à 17 UI/L avec un rapport moyen pic LH/ pic FSH de 1,30. Les étiologies étaient comme suit: pubertés précoces dissociées (60,60%), pubertés précoces pathologiques (39,40%). Dans cette dernière, nous avons noté une prédominance des pseudo-pubertés précoces (58,98%). Pour la puberté précoce centrale, la forme idiopathique était l´étiologie la plus fréquente chez la fille (62,5%). Alors que chez tous les garçons, une lésion du système nerveux central était objectivée.Conclusionnotre étude confirme que la puberté précoce pathologique centrale est souvent liée à une lésion du système nerveux central chez le garçon justifiant ainsi la réalisation systématique d´une imagerie cérébrale.

Incidence and management of Osgood-Schlatter disease in general practice: retrospective cohort study.

BackgroundOsgood–Schlatter disease (OSD) is a non-traumatic knee problem that is primarily observed in sports-active children and adolescents aged 8–15 years.AimTo determine the incidence of OSD and to gain an insight into the management of children and adolescents with OSD in general practice.Design and settingA retrospective cohort study was conducted using a healthcare database containing full electronic health records of over 200 000 patients in general practice in and around the Dutch city of Rotterdam.MethodPatients with a new diagnosis of OSD from 1 January 2012 to 31 December 2017 were extracted using a search algorithm based on International Classification of Primary Health Care coding and search terms in free text. Data on the management of OSD were manually interpreted.ResultsThe mean incidence over the study period was 3.8 (95% confidence interval [CI] = 3.5 to 4.2) per 1000 person–years in those aged 8–18 years. Boys had a higher incidence rate of 4.9 (95% CI = 4.3 to 5.5) compared with girls (2.7, 95% CI = 2.3 to 3.2). Peak incidence was at 12 years of age for boys and 11 years for girls. Advice was the most commonly applied strategy (55.1%), followed by rest (21.0%), referral for imaging (19.5%), and physiotherapy (13.4%).ConclusionTo the authors’ knowledge, for the first time the incidence of OSD has been calculated using GP electronic medical files. There is a discrepancy, especially for imaging and referral to a medical specialist, between the current Dutch general practice guidelines and how GPs actually manage the condition in clinical practice.

Blood lead level and nutritional status indicators in preadolescent Polish schoolchildren

BackgroundEnvironmental pollutions with heavy metals may have toxic effects on human health and development. One of the most detrimental is lead exposure, which may disturb neurodevelopment and linear growth in children. However, data on the effect of lead exposure on nutritional and weight status in children are limited, thus this study aimed to assess the effect of blood lead (Pb) level on nutritional and weight status in preadolescent schoolchildren from the industrialized, mining region in southwestern Poland. MethodsOur study sample involved N = 709 schoolchildren (402 boys and 307 girls) in the preadolescent developmental period (7–11 years of age for boys and 7–10 years of age for girls). Anthropometric measurements were used to assess nutritional and weight status: body mass index (BMI), mid-upper arm circumference (MUAC) and skinfolds thicknesses (triceps, subscapular, abdominal and the sum of skinfolds). Blood Pb level was evaluated and divided into two groups: above (>3.7 μg/dL) and below median value (≤3.7 μg/dL). ResultsAnalysis of covariance (with children’s age controlled as a covariate) revealed that children with blood Pb level above median value had significantly lower values of BMI, MUAC and all skinfolds (at least p < 0.01). However, this effect was significant only in boys, whereas in girls differences were non-significant (p > 0.05). The highest effect size of blood Pb level was noted for skinfolds thicknesses (partial η2: 0.015 for the sum of skinfolds). ConclusionsNutritional status in children with higher blood Pb level is significantly impaired in preadolescent boys, who appear to be more sensitive to this environmental factor. Our findings indicate a particular need for nutritional and environmental interventions among preadolescent children in regions with higher lead exposure.

Prenatal exposure to residential PM2.5 and its chemical constituents and weight in preschool children: A longitudinal study from Shanghai, China

BackgroundStudies have reported that prenatal exposure to fine particulate matter (PM2.5) might be associated with adverse birth outcomes in offspring. However, evidence with regard to the effects of prenatal exposure to PM2.5 and, especially, its main chemical constituents on offspring’s weight in childhood is limited and inconsistent. ObjectivesThe present study aimed to examine associations of prenatal exposure to PM2.5 total mass and its chemical constituents in each trimester with children’s weight from birth to 6 years of age using data from Shanghai-Minhang Birth Cohort Study. MethodsA total of 1,084 mother-infant pairs were included with both PM2.5 exposure data and at least one measurement of weight and height. Weight-for-Length (WLZ), BMI-for-Age (BMIz), and Weight-for-Age (WAZ) z-scores were generated according to the World Health Organization guidelines. Exposure to PM2.5 total mass and its chemical constituents [organic carbon (OC), black carbon (BC), ammonium (NH4+), nitrate (NO3−), sulfate (SO42−), and soil dust (SOIL)] during pregnancy was estimated from a satellite based modelling framework. We used multiple informant model to estimate the associations of trimester-specific PM2.5 total mass and its specific constituents concentrations with WLZ/BMIz and WAZ of offspring at birth and 1, 4, and 6 years of age. ResultsIn multiple informant model, we observed consistent patterns of associations between exposure to PM2.5 total mass, OC, BC, NH4+, NO3−, and SO42− during the 2nd and 3rd trimesters and decreased WLZ/BMIz and WAZ at 1, 4, and 6 years of age in boys. We observed associations between prenatal exposure to PM2.5 total mass, NH4+, and NO3− during the 1st and 2nd trimesters and increased WLZ/BMIz and WAZ in girls at birth. However, there were null associations at 1 and 4 years of age and inverse associations at 6 years of age. ConclusionsPrenatal exposure to PM2.5 total mass and its main chemical constituents was associated with decreased weight in boys from 1 to 6 years of age, with increased weight at birth and decreased weight at 6 years of age in girls. Our findings suggest that prenatal exposure to PM2.5 and its chemical constituents may have a lasting effect on offspring’s weight in childhood.

Diagnosis and management of precocious sexual maturation: an updated review.

The classic definition of precocious sexual maturation is the development of secondary sexual characteristics before 8 years of age in girls and before 9 years of age in boys. It is classified as central precocious puberty when premature maturation of the hypothalamic-pituitary-gonadal axis occurs, and as peripheral precocious puberty when there is excessive secretion of sex hormones, independent of gonadotropin secretion. Precocious sexual maturation is more common in girls, generally central precocious puberty of idiopathic origin. In boys, it tends to be linked to central nervous system abnormalities. Clinical evaluation should include a detailed history and physical examination, including anthropometric measurements, calculation of growth velocity, and evaluation of secondary sexual characteristics. The main sign to suspect the onset of puberty is breast tissue development (thelarche) in girls and testicular enlargement (≥4 mL) in boys. Hormonal assessment and imaging are required for diagnosis and identification of the etiology. Genetic testing should be considered if there is a family history of precocious puberty or other clinical features suggestive of a genetic syndrome. Long-acting gonadotropin-releasing hormone analogs are the standard of care for central precocious puberty management, while peripheral precocious puberty management depends on the etiology.Conclusion: The aim of this review is to address the epidemiology, etiology, clinical assessment, and management of precocious sexual maturation. What is Known: • The main sign to suspect the onset of puberty is breast tissue development (thelarche) in girls and testicular enlargement (≥4 mL) in boys. The classic definition of precocious sexual maturation is the development of secondary sexual characteristics before 8 years of age in girls and before 9 years of age in boys. • Long-acting gonadotropin-releasing hormone agonist (GnRHa) is the standard of care for CPP management, and adequate hormone suppression results in the stabilization of pubertal progression, a decline in growth velocity, and a decrease in bone age advancement. What is New: • Most cases of precocious sexual maturation are gonadotropin-dependent and currently assumed to be idiopathic, but mutations in genes involved in pubertal development have been identified, such as MKRN3 and DLK1. • A different preparation of long-acting GnRHa is now available: 6-month subcutaneous injection.

Development of stratified normative data and reference equations for the timed up and down stairs test for healthy children 6–14 years of age

ObjectivesTo generate normative data on healthy children aged 6–14 years for the timed up and down stairs (TUDS) test, and to provide reference equations. Design and settingCross-sectional study at two primary schools. ParticipantsHealthy children 6–14 years of age. Main outcomes measuresAnthropometric data and Minnesota Leisure-Time Physical Activity Questionnaire from children were collected before the start of the TUDS test. Heart rate, blood pressure and perceived exertion were measured at the beginning and at the end of the test. Two trials of the TUDS test were performed with 15-minute of rest on the same day and the better of the two trials was used in the analyses. The reference equations were established using the anthropometric variables as possible predictors of the TUDS test. ResultsTwo hundred fifty eight children (125 boys and 133 girls) were assessed. The mean TUDS test score decreased significantly from 6 to 14 years of age in boys and girls alike, with statistically significant differences between the three age range groups. A significant difference was found between girls and boys in TUDS test score. The 56% of the variation in TUDS test score could be explained by age, height, and weight in boys [TUDSsec score=(9.967−(0.182×Ageyears)+(0.025×Weightkg)−(2.546×Heightm)], while 50% could be explained in girls [TUDSsec score=10.553−(0.194×Ageyears)+(0.019×Weightkg)−(2.406×Heightm)]. The inclusion of physical level activity increased the variability explained (boys: 59%; girls: 51%). ConclusionsTUDS score improved as the age of the children increased, with boys achieving better values than girls within each age group. TUDS test score can be easily predicted from age, height, and weight. The inclusion of the child's physical activity level increased the variance explained by the equation.

Recovery of hypothalamus-pituitary-gonadal dysfunction after the treatment of suprasellar germ cell tumors.

To investigate the incidence of hypothalamus-pituitary-gonadal (HPG) axis initiation/recovery after treatment and to identify predictive risk factors for noninitiation/recovery. A total of 127 consecutive suprasellar germ cell tumor (GCT) patients managed at Peking Union Medical College Hospital (2006-2019) were retrospectively analyzed. Prepubertal patients (followed up until 13 years of age for girls and 14 years of age for boys) and patients with HPG dysfunction (followed up for 2 years) were divided into the initiation/recovery and noninitiation/recovery groups. Of the 127 suprasellar GCT patients, 75 met the follow-up criteria, 28 (37.3%) of whom experienced HPG axis initiation/recovery. Compared to the noninitiation/recovery group, the initiation/recovery group included more males and had shorter delayed diagnosis times, smaller tumor sizes, lower panhypopituitarism rates, thinner pituitary stalk widths, lower visual deficit rates, and higher serum testosterone and estradiol levels. The cutoff values of pituitary stalk width, tumor size, and delayed diagnosis time used to predict noninitiation/recovery were 6.9 mm, 6.9 mm and 1.7 years, respectively. Tumor size ≥6.9 mm (odds ratio (OR) = 7.5, 95% CI: 2.2-25.8, P = 0.001), panhypopituitarism (OR = 5.0, 95% CI: 1.4-17.6, P = 0.013), and delayed diagnosis time ≥1.7 years (OR = 5.7, 95% CI: 1.5-20.7, P = 0.009) were risk factors for noninitiation/recovery. Among suprasellar GCT patients, nearly one-third of prepubertal patients and patients with HPG dysfunction experience HPG axis initiation/recovery after treatment. Tumor size ≥6.9 mm, panhypopituitarism, and delayed diagnosis time ≥1.7 years were identified as predictive risk factors for noninitiation/recovery.

Fathers\u2019 Mental Health and Children\u2019s Aggressive Behaviour A Study Based on Data from the Norwegian Mother, Father and Child Cohort Study (MoBa)

The aim of the study was to examine the association between fathers’ prenatal psychological distress and children’s aggressive behaviour in terms of hitting others, and how children’s age, gender and temperament affect this association. The study is based on data from 20,155 fathers and mothers from the Norwegian Mother, Father and Child Cohort Study (MoBa). Fathers and mothers completed questionnaires at 17 or 18 weeks of gestation and mothers at children’s age 18 months, and 3 and 5 years. Fathers’ prenatal psychological distress was assessed by the 5-item Symptom Checklist (SCL-5), and children’s temperament by 12 items from the Emotionality Activity Sociability (EAS) Temperament Survey. Increasing prenatal psychological distress in fathers was associated with an increase of hitting from 18 months to 3 years of age in boys. Children’s temperament did not affect the association between fathers’ prenatal psychological distress and children’s aggressive behaviour.

LITERATURE REVIEW: ´´

Earl puberty begins with activation of the gonadotrophic axis before 8 years of age in girls and at 9 years of age in boys. One of the main concerns is the height because it accelerates the bone maturation process resulting in reduced height. The standard treatment for precocious puberty is the use of deposits of GnRh analogues with the proposal to minimize the effects on growth. As a result, this literature review is based on demonstrating the effects of using GnRh analogues at the final height. Before and after 8 years of age.

Selected abstracts presented at the annual conference of the Canadian Society of Clinical Chemists (CSCC), 2020

Alkaline phosphatase (ALP) serves as a biomarker for diagnosing several types of diseases in adults; nonetheless, its use is restricted in children because of changes in ALP activity during different physiological phases. The present study aimed to investigate ALP activity and its dynamics in children of different ages to establish the reference values for ALP activity in children.Total 167,625 samples of children aged 0–18 years were enrolled in this study. ALP activity was measured using the 4-nitrophenyl-1-phosphate disodium salt (4-NPP)–2-amino-2-methyl-1-propanol (AMP) method with an automatic biochemical analyzer. Patients with known diagnoses that may affect ALP activity were excluded. A percentile curve was plotted using MATLAB software, and the curve was fitted using the skewness–median–coefficient of variation (LMS) method.ALP activity reached the highest peak at 12–13 years of age and then gradually decreased to the lowest peak at 18–19 years of age in boys, whereas it reached the highest at 10–11 years and then gradually reduced to the lowest at 17–18 years in girls. Furthermore, the highest peak of ALP activity appeared substantially earlier in children of either sex in China than in those in Germany.We showed the dynamics of ALP activity in both boys and girls between the ages of 0 and 18 years in China and compared the difference in ALP activity between children in China and Germany. Our findings provide a reference for clinicians.

Fenilketonüri ve Puberte Prekoks Birlikteliği: Bir vaka sunumu

Phenylketonuria (PKU) is one of the most common preventable causes of intellectual disability resulting from deficiency of phenylalanine hydroxylase enzyme activity. Precocious puberty (PP) is characterized by premature breast and pubic hair development, and advanced bone age development before 8 years of age for girls and 9 years of age for boys. We present a 7 years old girl with phenylketonuria and overweight, who has developed early puberty. PKU was confirmed by plasma amino acid analysis at newborn.At the age of 7, the first signs of PP appeared (T3). Laboratory tests were detected as luteinizing hormone 0.36 mIU/mL; follicule stimulating hormone 1.1 mIU/mL; estradiol 20 pg/mL; and bone age was 9 years. The response to gonadotropin-releasing hormone stimulation test was characteristic for true PP (LH 5.4 mIU/mL; FSH 8 mIU/mL). According to our current knowledge, the reason for this union isn’t clear. However, this association may be incidental or secondary to overweight and may also be secondary to phenylketonuria - good / bad metabolic control. It’s thought that PP cases may be seen more frequently due to the increase of obesity frequency in PKU patients.

Age-wise trends in alkaline phosphatase activity in 167,625 Chinese children aged 0–18 years

ObjectiveAlkaline phosphatase (ALP) serves as a biomarker for diagnosing several types of diseases in adults; nonetheless, its use is restricted in children because of changes in ALP activity during different physiological phases. The present study aimed to investigate ALP activity and its dynamics in children of different ages to establish the reference values for ALP activity in children. MethodsTotal 167,625 samples of children aged 0–18 years were enrolled in this study. ALP activity was measured using the 4-nitrophenyl-1-phosphate disodium salt (4-NPP)–2-amino-2-methyl-1-propanol (AMP) method with an automatic biochemical analyzer. Patients with known diagnoses that may affect ALP activity were excluded. A percentile curve was plotted using MATLAB software, and the curve was fitted using the skewness–median–coefficient of variation (LMS) method. ResultsALP activity reached the highest peak at 12–13 years of age and then gradually decreased to the lowest peak at 18–19 years of age in boys, whereas it reached the highest at 10–11 years and then gradually reduced to the lowest at 17–18 years in girls. Furthermore, the highest peak of ALP activity appeared substantially earlier in children of either sex in China than in those in Germany. ConclusionsWe showed the dynamics of ALP activity in both boys and girls between the ages of 0 and 18 years in China and compared the difference in ALP activity between children in China and Germany. Our findings provide a reference for clinicians.

Prenatal Manganese Exposure and Long-Term Neuropsychological Development at 4 Years of Age in a Population-Based Birth Cohort.

Background: Manganese (Mn) is an essential micronutrient for humans, the diet being the main source of exposure. Some epidemiological studies describe a negative association between prenatal Mn and later neuropsychological development, but results are inconsistent. The aim of this study was to explore the association between prenatal Mn exposure and neuropsychological development assessed at 4 years of age. Methods: Study subjects were 304 mother-child pairs from the Gipuzkoa cohort of the INMA (Environment and Childhood) Project. Mn was measured in newborns’ hair. Children’s neuropsychological development was assessed at 4 years of age using the McCarthy Scales of Children’s Abilities. Multivariate linear regression models were built. Stratified analysis by sex was performed. Generalized additive models were used to assess the shape of the relation. Results: The median Mn concentration in newborns’ hair was 0.42 μg/g (95% CI = 0.38, 0.46). The association between Mn levels and the neuropsychological development was not statistically significant for the general cognitive scale (β [95% CI] = 0.36 [−5.23, 5.95]), motor scale (β [95% CI] = 1.9 [−3.74, 7.55]) or any of the other outcomes. No sex-specific pattern was found. The best shape describing the relationship was linear for all the scales. Conclusion: Our results suggest that prenatal Mn concentrations measured in newborns’ hair do not affect cognitive or motor development at 4 years of age in boys or in girls at the observed Mn levels.

One-Year Age Increment and Sex Differences in the Relationship between Long-Term Exposure to PM 2.5 and Fasting Plasma Glucose Levels in Chinese Children and Adolescents Aged 6-17 Years: Exploring an Independent Risk Factor and Precise Intervention Time Clues

Background: Previous studies on the association of PM2.5 exposure with fasting plasma glucose levels (FPGLs) are limited to short- and mid- term PM2.5 exposure duration and lack adjustments for key confounders. Systematically exploring the relationship between long-term PM2.5 exposure and FPGLs in Chinese children and adolescents aged 6-17 years is a necessity. Methods: Between September 2013 and December 2013, 16489 participants aged 6-17 years were recruited using a four-staged, stratified, cluster sampling strategy from 7 provinces, autonomous regions and municipalities on the Chinese mainland. A generalized linear mixed model (GLMM) was used to estimate the relationship of annual PM2.5 exposure (2007-2013) with FPGLs stratified by sex and one-year age increments. Sociodemographics, whether living with parents, early-life factors, behaviors, and infection symptoms were gradually adjusted from the crude model to regression model 6; BMI was adjusted in model 7. Findings: The annual concentration of PM2.5 was 56·23 (±12·99) µg/m3. The mean FPGLs of the 8551 boys (4·75 mmol/L±0·52) was significantly higher than that of the 8194 girls (4·63 mmol/L±0·48). In model 6, each 1 I¼g/m3 increase in PM2.5 was associated with point estimates (95% CIs) of FPGLs of 0·0045 (0·0028 to 0·0063) mmol/L (pi¼œ0·0001) and 0·0050 (0·0035 to 0·0065) mmol/L (pi¼œ0·0001) for boys and girls, respectively. FPGLs were significantly positively associated with long-term PM2.5 exposure at 12, 15 and 16 years old in both boys and girls, accompanied by age differences in model 7. The prevalence of impaired fasting plasma glucose (IFPG) decreased by 0·18% in model 6; assessing the negative effects of PM2.5 exposure revealed that 29,226 children and adolescents would have been protected from IFPG in 2013 in China. Interpretation: Long-term PM2.5 exposure may be an independent risk factor for elevated FPGLs. The adverse effect of PM2.5 exposure on FPGLs in children and adolescents could appear after 10 years of cumulative exposure time. Clues regarding the precise intervention time were revealed at approximately 12 and 11 years of age in boys and girls, respectively. There are great public health implications of early prevention strategies to eradicate the negative effects of long-term exposure to PM2.5 on FPGLs. Funding Statement: Public Welfare Industry of Health of the Ministry of Health of China; National Natural Science Foundation of China. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: The project was approved by the ethics committee of Peking University. All participants and their parents voluntarily signed the informed consent form.

Postnatal Exposure of PM10 and Autistic Behaviours among Children: The Mothers and Children's Environmental Health (MOCEH) Study

Background/AimEnvironmental factors may play a role in the development of neurodevelopment and some studies have shown that ambient air pollution is associated with the autistic behaviours. The study was designed to investigate the impact of outdoor air pollution on autistic behaviours among children at 4, 5 years of age in Korea by using MOCEH cohort study's data.MethodsThis study is a part of the Mothers and Children's Environmental Health (MOCEH) study, a Korean multi-center prospective birth cohort study initiated in 2006. After delivery, children were followed up at 48 and 60 months of age. Average exposure level of particulate matter (PM10) were estimated using the inverse distance weighting (IDW) method from prenatal period to postnatal period. A total of 322 mother-child pairs were included. Autistic behaviours were assessed using the Social Responsiveness Scale (SRS) at 4, 5 years of age. We also examined the result stratified by sex of the children.ResultsThe average levels of PM10 during pregnancy and 3 years of age were 54.07&amp;#956;g/m3 and 50.08&amp;#956;g/m3 each. In a multiple linear regression model, although we couldn&amp;#8217;t find significant positive relationship between exposure of PM10 in children, we found that PM10 at 3 years of age was associated with increased scores of SRS T-scores at 5 years of age in boys. (&amp;#946;&amp;#61;0.36, 95% confidence interval [CI]: 0.05,0.66) However, there was no significant positive association in girls.ConclusionsIn conclusions, postnatal exposure of PM10 is associated with the autistic behaviours, in boys at 4, 5 years of age. Further study on the other air pollutants effects to autistic behaviours in children is recommended.

Management of Clavicle Fractures in Adolescents

* The clavicle grows at a constant rate (8.4 mm per year) and achieves 80% of its length by 9 years of age in girls and 12 years of age in boys.* There is no consensus with regard to the optimal treatment approach to midshaft clavicle fractures in adolescent patients.* Complications from nonoperative treatment, including malunion and nonunion, are rare but are associated with increasing age in adolescent patients.* In the absence of skin tenting, comminution, or marked displacement or shortening, simple closed midshaft clavicle fractures may be safely treated without radiographic follow-up and/or in the primary care setting.* Reported rates of complications following operative management of clavicle fractures vary widely. The implant fixation construct is based on fracture and patient characteristics and is at the discretion of the treating surgeon; however, Kirschner wire fixation should be avoided because of an unacceptable rate and severity of complications.

Isometric muscle strength in children and adolescents using Handheld dynamometry: reliability and normative data for the Brazilian population

ObjectiveIsometric muscle strength measured by Handheld dynamometer indicates physical ability. There is no normative data for the Brazilian population. This study aims (a) to describe the development of isometric muscle strength in healthy children and adolescents 5–15 years of age; (b) to evaluate Handheld dynamometer inter and intra-rater reliability. MethodsIsometric muscle strength was obtained for shoulder abduction, elbow and knee flexion and extension, dorsiflexion and plantar flexion in 55 boys and 55 girls, aged between 5 and 15 years. Inter-rater reliability was determined based on the evaluation of 2 raters, with a 20-min interval between them. Intra-rater reliability was based on 2 evaluations from the same rater, one week apart. Interclass correlation coefficient (ICC2,1; 3,1), Bland Altman plots and linear regression models with mixed effects were used to quantify inter and intra-rater reliability, agreement and associations with physical activity level and maturational factors. ResultsA linear development of isometric muscular strength was observed for ages between 5 and 10. After age 10, boys showed a larger isometric muscular strength, when compared to girls. Both inter and intra-rater measurements of the Handheld dynamometer are reliable (ICC>0.63). ConclusionsThis study shows increase in isometric muscle strength starting at 10 years of age for boys, when compared to girls and inter and intra-rater reliability for the assessment of isometric strength, using the Handheld dynamometer for the muscle groups tested on the dominant and non-dominant side, for children between 5 and 15 years of age.