Increased Carbohydrate Induced Ghrelin Secretion in Obese vs. Normal‐weight Adolescent Girls

Orexigenic and anorexigenic pathways mediate food intake and may be affected by meal composition. Our objective was to determine whether changes in levels of active ghrelin and peptide YY (PYY) differ in obese vs. normal‐weight adolescent girls following specific macronutrient intake and predict hunger and subsequent food intake. We enrolled 26 subjects: 13 obese and 13 normal‐weight girls, 12–18 years old, matched for maturity (as assessed by bone age) and race. Subjects were assigned a high‐carbohydrate, high‐protein, and high‐fat breakfast in random order. Active ghrelin and PYY were assessed for 4 h after breakfast and 1 h after intake of a standardized lunch. Hunger was assessed using a standardized visual analog scale (VAS). No suppression in active ghrelin levels was noted following macronutrient intake in obese or normal‐weight girls. Contrary to expectations, active ghrelin increased in obese girls following the high‐carbohydrate breakfast, and the percent increase was higher than in controls (P = 0.046). Subsequent food intake at lunch was also higher (P = 0.03). Following the high‐fat breakfast, but not other breakfasts, percent increase in PYY was lower (P = 0.01) and subsequent lunch intake higher (P = 0.005) in obese compared with normal‐weight girls. In obese adolescents, specific intake of high‐carbohydrate and high‐fat breakfasts is associated with greater increases in ghrelin, lesser increases in PYY, and higher intake at a subsequent meal than in controls. Changes in anorexigenic and orexigenic hormones in obese vs. normal‐weight adolescents following high‐carbohydrate and high‐fat meals may influence hunger and satiety signals and subsequent food intake.     

Changes in lung, airway, and chest wall function in boys and girls between 8 and 12 yr

Maximum expiratory flows, maximum inspiratory and expiratory pressures, and lung volumes were measured in 248 8-yr-old and 215 12-yr-old healthy school children. Eight-year-old girls had smaller total lung capacity but higher volume-corrected expiratory flows than boys. Maximum expiratory flow and total lung capacity increased more in girls than in boys between 8 and 12 yr. Girls had a greater increase in residual volume (0.23 liter for girls, 0.16 liter for boys) as well as lower maximum expiratory and inspiratory pressures (P less than 0.001). Girls have smaller lung volumes than boys, so one would expect smaller airways in girls, but girls generate greater flows, indicating that their airways are possibly wider than those of boys. There is also evidence of unequal growth of the airways and air spaces between 8 and 12 yr. Chest wall development appears less in girls than boys and the difference becomes more marked at 12 yr.     

Comparison of Attitudes and Behaviors Related to Nutrition,Body Size,Dieting, and Hunger in Russian,Black-American,and White-American Adolescents

Attitudes and behaviors related to nutrition are known to differ between white-American and black-American adolescents, however, little is known about teenagers from Russia. We hypothesized that, compared with white-American or black-American teenagers, Russian teenagers would prefer a larger body size, be less likely to diet, and be less concerned about being overweight. Self-administered questionnaires were completed by 196 students in Moscow, 326 white-American, and 239 black-American adolescents who attended school in North Carolina (mean age = 16). Ideal body mass index (BMI) was calculated from measured height and the response to the question, “What do you consider to be your ideal weight?” Mean ideal BMI was higher in black-American boys (25.1) and girls (21.4) than in white-American boys (22.1) and girls (19.2), and Russian boys (21.8) and girls (19.1). After controlling for BMI, black-American girls were less than half as likely to report dieting compared with white-American girls. There were no significant differences among white-American girls and Russian girls, and there were no ethnic differences between boys in the prevalence of dieting. White-American girls and black-American girls were much more likely to identify being overweight as an important nutritional concern than were Russian girls (odds ratios >10), and there were no ethnic differences among boys. We conclude that preferences for body size, the prevalence of dieting, and concerns about being overweight were similar in Russian and white-American teens, with the exception of Russian teenaged girls who were less likely than American girls to identify being overweight as an important concern. Overall, weight-related attitudes and behaviors in Russian teenagers were more similar to those of white-American teenagers than those of black-American teenagers.     

The Relationship of Weight‐Related Attitudes With Suicidal Behaviors in Korean Adolescents

The objective of this study was to assess the relationship between weight‐related attitudes and suicidal behavior after consideration of depressive mood in Korean adolescents. The study population consisted of a nationally representative sample of 74,698 adolescents (n = 39,466 boys, 35,232 girls) in middle and high school who completed the Korea Youth Risk Behavior Web‐based Survey (KYRBWS) in 2007. Logistic regression models were used to examine the relationships between measures of weight‐related and self‐reported suicidal behavior, controlling for demographics, depressive mood, stress perception, level of school achievement, and substance use. Suicide attempts were surveyed among those reported to have suicidal ideation (n = 7,579 boys, 10,204 girls). Significantly more girls than boys reported suicidal ideation (29 vs. 19%) and suicide attempts (7.7 vs. 4.5%). Factors significantly associated with suicidal ideation were overestimation of weight (vs. correct estimation) and behaviors to lose or gain weight (vs. no weight control) among boys and overestimation of weight and attempting to lose weight among girls. In contrast, the odds of suicide attempts were significantly higher among boys who tried to lose, gain, or maintain their weight (vs. no weight control) and girls who underestimated their weight (vs. correct estimation) and tried to lose weight (vs. no weight control). Boys and girls classified as overweight or at risk for overweight were significantly less likely to report suicide attempts compared to those classified as underweight. Weight‐related attitudes, such as incorrect weight perception and weight control behaviors, seem to be useful indicators for identifying Korean adolescents who are at risk for suicidal behaviors.     

Elevated blood pressure in school children and adolescents--prevalence and associated risk factors

Elevated blood pressure (BP) in children and adolescents is determined on normative distribution of BP in healthy children. The aim of this study was to determine prevalence of high normal and elevated BP among school children and to assess associated risk factors. The study comprised 965 children (48.7% girls) in 8th grade of primary school. Data were obtained from questionnaire and anthropometric measurements. The prevalence of high normal BP was 28.5% in girls, 36.8% in boys, and elevated BP 7.9% in girls and 5.3% in boys. Overweight was present in 19.4% of girls and 9.3% boys with high normal, and 29.7% of girls and 30.8% boys with elevated BP. Hypertension in family history was the most common associated factor reported by boys and girls with high normal and elevated BP. Follow-up of children throughout school age makes possible taking of preventative measures and promotion of healthy life style.     

游泳训练对儿童最大有氧活动能力的影响

本文利用步行机对９１名８－１１岁男女儿童进行最大有氧活动能力的测试,其中训练组４２人选自北京市海滨区业余游泳队的儿童,对照组４９人（男２４人,女２５人）选自与训练组儿童条件相近的普通学校学生。观察９个月的游泳训练对儿童有氧活动能力的影响。研究结果表明,训练组儿童的身高,体重,瘦体重和肺活量在观察前及观察后的两次测试中均高于对照组。观察期间形态指标的增长值和两组值在两组间大都无明显差别,表明两组儿童     

Physical activity levels of normal-weight and overweight girls and boys during primary school recess

Objective: This study aimed to compare moderate‐to‐vigorous physical activity (MVPA) and vigorous physical activity (VPA) in normal‐weight and overweight boys and girls during school recess. Research Methods and Procedures: Four hundred twenty children, age 6 to 10 years, were randomly selected from 25 schools in England. Three hundred seventy‐seven children completed the study. BMI was calculated from height and weight measurements, and heart rate reserve thresholds of 50% and 75% reflected children's engagement in MVPA and VPA, respectively. Results: There was a significant main effect for sex and a significant interaction between BMI category and sex for the percent of recess time spent in MVPA and VPA. Normal‐weight girls were the least active group, compared with overweight boys and girls who were equally active. Fifty‐one boys and 24 girls of normal weight achieved the 40% threshold; of these, 30 boys and 10 girls exceeded 50% of recess time in MVPA. Eighteen overweight boys and 22 overweight girls exceeded the 40% threshold, whereas 8 boys and 8 girls exceeded the 50% threshold. Discussion: Overweight boys were significantly less active than their normal‐weight male counterparts; this difference did not hold true for girls. Even though nearly double the number of normal‐weight children achieved the 40% of MVPA during recess compared with overweight children, physical activity promotion in school playgrounds needs to be targeted not only at overweight but at other health parameters, as 40 overweight children met the 40% MVPA target proposed for recess.     

Epidemiological survey for the prevalence of overweight and abdominal obesity in Greek adolescents

This study was designed to provide estimates of overweight (OW), obesity (OB), and abdominal OB (AO) in a representative sample of adolescents throughout the whole of Greece. A total of 14,456 adolescents aged 13-19 years (6,677 boys and 7,779 girls) had direct measurements (height, weight, waist circumference (WC)) taken at school during 2003. The overall prevalence of OW including OB in the population studied was 29.4% in boys and 16.7% in girls. OB prevalence was also higher in boys than in girls (6.1% vs. 2.7%), whereas prevalence of AO was higher in girls than in boys (21.7% vs. 13.5%). Rates of OW, OB, and AO were significantly more prevalent in the Greek than in the foreign male population (immigrants). OW% in adolescent girls was independently associated with smoking and alcohol consumption. The prevalence of OW and OB in Greek adolescents is high, particularly in boys, comparable with that reported for most Mediterranean European countries. AO, mainly in adolescent girls, also appears high. Preventive and treatment strategies are urgently needed to combat this OB epidemic in Greece.     

Feeding of school children in a London borough.

A survey of 12 schools in a London borough showed that the protein and energy content of the average school meal was below the standard set by the Department of Health and Social Security for all age groups. Failure to meet the standards resulted from inadequate food purchases, poor menu planning and portion control, and several management problems. A 24-hour recall questionnaire showed that 5% of the pupils were "poorly" fed. These pupils were, however, no worse off than their "adequately" fed peers with regard to absences from school or academic attainment measured by reading quotient, but there was some slight difference in height and weight. The percentage of children having no breakfast increased from 4% in the infant schools to 21% in the senior schools. Two per cent of the senior pupils regularly ate no lunch.     

Neural responses to visual food stimuli after a normal vs. higher protein breakfast in breakfast-skipping teens: a pilot fMRI study

This functional magnetic resonance imaging (fMRI) pilot study identified whether breakfast consumption would alter the neural activity in brain regions associated with food motivation and reward in overweight "breakfast skipping" (BS) adolescent girls and examined whether increased protein at breakfast would lead to additional alterations. Ten girls (Age: 15 ± 1 years; BMI percentile 93 ± 1%; BS 5 ± 1×/week) completed 3 testing days. Following the BS day, the participants were provided with, in randomized order, normal protein (NP; 18 ± 1 g protein) or higher protein (HP; 50 ± 1 g protein) breakfast meals to consume at home for 6 days. On day 7 of each pattern, the participants came to the laboratory to consume their respective breakfast followed by appetite questionnaires and an fMRI brain scan to identify brain activation responses to viewing food vs. nonfood images prior to lunch. Breakfast consumption led to enduring (i.e., 3-h post breakfast) reductions in neural activation in the hippocampus, amygdala, cingulate, and parahippocampus vs. BS. HP led to enduring reductions in insula and middle prefrontal cortex activation vs. NP. Hippocampal, amygdala, cingulate, and insular activations were correlated with appetite and inversely correlated with satiety. In summary, the addition of breakfast led to alterations in brain activation in regions previously associated with food motivation and reward with additional alterations following the higher-protein breakfast. These data suggest that increased dietary protein at breakfast might be a beneficial strategy to reduce reward-driven eating behavior in overweight teen girls. Due to the small sample size, caution is warranted when interpreting these preliminary findings.     

Sociocultural Factors and School Engagement Among African American Youth: The Roles of Racial Discrimination,Racial Socialization,and Ethnic Identity

This study investigated the links between racial discrimination and school engagement and the roles of racial socialization and ethnic identity as protective factors in those linkages in a sample of 148, sixth through twelfth grade African American adolescents from working and middle-class two-parent families. In home interviews, youth described their ethnic identity, discrimination experiences at school, and school engagement (school bonding, school grades, school self-esteem), and parents rated their racial socialization practices. Analyses revealed that discrimination was negatively related to school self-esteem and school bonding. Racial socialization had additive effects on school self-esteem and school bonding, but did not moderate the discrimination—school engagement association. For boys, ethnic identity had additive effects on school bonding, but for girls, ethnic identity moderated the relation between discrimination and school bonding: when girls experienced more discrimination and had a lower ethnic identity, they reported lower school bonding. Discrimination, racial socialization, and ethnic identity were not related to school grades.     

Peers, teachers and parents as assessors of the behavioural and emotional problems of twins and their adjustment: the Multidimensional Peer Nomination Inventory.

A multidimensional peer nomination inventory (MPNI; 30 items) and parallel versions--MPNI-Teacher and MPNI-Parental Rating Forms (37 items each)--were developed during a major new Finnish study of families with twins. The twins (477 girls and 467 boys) were 12 years old, representing subsets of three nationwide Finnish twin cohorts (b. 1983-1985). They were enrolled in 503 school classes, and the total number of children participating in peer nominations was 12,937. Three main factors were extracted from peer nominations and teacher and parental assessments. Intercorrelating sub-components were found, especially in parental assessments. Scales were formed, accordingly, for Behavioral Problems (including Hyperactivity-Impulsivity, Aggression, and Inattention), Emotional Problems (including Depression and Social Anxiety), and Adjustment (including Constructiveness, Compliance, and Social Activity). A framework for the development of the multidimensional inventory was a model of emotional and behavioural regulation. Peer nominations were most reliable, while parental assessments, although mostly satisfactory, were least reliable. Results provided evidence of concurrent validity of peer-referenced assessment, using teacher assessments as criteria; correlations between assessments of peers and parents were lower. The inventory has discriminative validity. Intra-pair correlations of monozygotic co-twins were higher than correlations of same-sex (SS) and opposite-sex (OS) dizygotic (DZ) co-twins for all scales across all three assessors, and peer nominations of both SS and OSDZ co-twins yielded correlations significantly greater than zero for all scales. All scales, except Depression and Social Anxiety, differentiated boys from girls.     

Changes in anthropometrical characteristics during two years in 6 year old children

The purpose of this study was to investigate changes in anthropometrical characteristics during the last year (autumn-spring) in preschool and first year (autumn-spring) in school. Changes in anthropometrical characteristics during summer months were also studied (spring-autumn). The subjects were 130 boys and 122 girls, 6 years of age at the beginning of the investigation. The body height and mass were measured and the BMI (kg/m2) was calculated. In total, eight skinfolds, 10 girths and two bone widths were measured. In boys, the body height and mass were higher than in girls, while the skinfold thicknesses were thicker in girls. There were only very few significant differences between sexes in girth parameters. The width parameters were higher in boys. Our results indicated that there were more significant changes in skinfold thickness, girths and width parameters during winter in preschool in comparison with first year in school in boys, while there were only a very few significant changes during summer months in boys. In contrast, there were more significant changes in school in girls. The Spearman correlations between baseline and after 6, 12 and 18 months of study indicated that the tracking of body height was high in boys and girls. Body mass tracking was high in girls and moderate in boys, while BMI tracking was moderate in both groups. The tracking coefficients of skinfold thicknesses were relatively stable during the two years of study and mostly at the moderate level (r = 0.3-0.6). Tracking coefficients of girths measures were at moderate level, but lower in boys in comparison with girls. It was concluded that social changes and probably changes in the physical activity during transition from preschool to school slightly influenced the measured anthropometrical parameters.     

某军医大学学生2013年营养及体能状况调查

目的:探讨某军医大学学生2013年某一时段营养及体能情况,以提高军校医学生身体素质。方法:选取2013年1月~2013年2月某军医大学在学校餐厅集体就餐的学员682人,采用称重法调查膳食,测定学员体重、身高,计算体重指数(BMI),对学员的体能状况进行测试。结果:调查学生蛋类、食用油摄入过多,而禽肉、豆类、蔬菜、牛奶、水果等均低于军标;Vit A、Vit C以及钙元素每日摄入量明显不足;学生每日获得热能的分配比例较好,均已达到军标;调查学生中男生体能状况优于女生(x2=22.035,P0.001),女生的超重人数明显多于男生(x2=20.142,P0.001)。结论:建议该校对餐厅炊事人员增加供应学生的食物品种,特别是水产、牛奶等富含优质蛋白的食品;强化学生体育锻炼的监督和指导工作,帮助他们增强自身体质,为国防现代化服务。     

Out-of-school experience categories influencing interest in biology of secondary school students by gender: exploration on an Abu Dhabi sample

This study employed the international Relevance of Science Education questionnaire to survey the interest in biology and the out-of-school experiences of Abu Dhabi secondary school students (median age 17, mean age 17.53 and mode age of 16) in the third semester of 2014. It included 3100 participants. An exploratory factor analysis was used to categorise the items for both interest in biology and out-of-school experience. Ten interest in biology and 12 out-of-school experience factors were extracted. The summated means for each factor indicated that ‘health and fitness’ and ‘disease control’ enjoyed highest interests among students. For out-of-school experiences, the two factors of ‘digital applications’ and ‘medical treatment’ received the highest scores. Multivariate analysis of variance revealed that all factors for both interest in biology and out-of-school experience exhibited significant differences between boys and girls. More girls than boys were interested in disease control, reproduction (human biology), alternative science, health and fitness, zoology, and applied cosmetic biology. No significant differences were observed for the remaining five other categories. Furthermore, analysis of variance revealed significant differences between boys and girls with regard to individual items comprising each of the factors. The highest correlations were between the two factors of out-of-school experiences of ‘the natural world’ and ‘learning through observation’ and the interest in biology factor related to ‘plant and animal farming and agriculture’. Results suggested that more emphasis must be placed on students’ out-of-school experience and their engagement in informal learning in contextual outdoor environments to enhance their interest in learning more about biology and the living environment in general.     

Prevalence of overweight among Baltimore City schoolchildren and its associations with nutrition and physical activity

Objective: To determine the prevalence of overweight and at‐risk‐for‐overweight in schoolchildren from Baltimore City. Research Methods and Procedures: Ten schools within city limits were randomly selected from each tertile of income, using eligibility for free school lunch as a proxy. A total of 209 third grade students from eight public schools in Baltimore City were surveyed in May 2000. Anthropometric data including height, weight, subscapular and triceps skinfold thickness, and percentage body weight from bioelectrical impedance were collected. Nutrition‐related knowledge, attitudes, and behaviors were assessed using a validated questionnaire. Physical activity was assessed by questionnaire. Results: Based on International Obesity Taskforce reference values for BMI‐for‐age, 20.7% of girls and 17.2% of boys were overweight (BMI > 95th percentile) and 15.3% of girls and 14.1% of boys were at‐risk‐for‐overweight (BMI between the 85th and 95th percentiles). The prevalence of overweight and at‐risk‐for‐overweight did not vary by self‐reported physical activity levels or by nutrition‐related knowledge and behaviors. Discussion: The high prevalence of overweight and at‐risk‐for‐overweight in this sample of inner‐city children from Baltimore City highlights a need for targeted preventive and treatment interventions.     

大连学生体质发育的研究

为了解大连地区城乡学生生长发育状况及其规律,采用人体测量学方法,调查测量了大连地区7—18岁3834（城市男630,城市女645,乡村男1285,乡村女1274）名汉族学生23项形态指标,并利用以往资料,研讨了大连学生主要形态指标的生长发育规律、生长发育趋势、性差和地区差别。结果表明：1生长发育特点：大连学生测量项目的均值随年龄的增长而增加,生长曲线呈上升趋势并且男女有交叉现象。2性差：大连学生各测量项目均有明显的性差,除女生青春期（10—12岁）外,在其他年龄组均为男生大于女生。3生长的长期变化：大连7—17岁男女学生26年来身高、体重、胸围有较大幅度的增长,其每10年平均增长值分别为2.52cm和1.92cm、4.05kg和2.39kg、1.77cm和1.38cm。4城乡差：大连男女学生身高、体重、胸围仍存在城乡差别。     

Birth Weight and Its Relationship to Size Attained and Relative Fat Distribution at 7 to 12 Years of Age

The relationship between birth weight and relative subcutaneous fat distribution at school age was considered in 131 boys and 106 girls 7 to 12 years of age. Relative fat distribution at school age was estimated with the ratio of the subscapular to triceps skinfolds (S/T) for the total sample, and with the ratio of the sum of two trunk (subscapular, midaxillary) to the sum of two extremity (triceps, medial calf) skinfolds (T/E) for subsamples of 102 boys and 63 girls. There were no sex differences in the S/T ratio (mm/mm), boys 0.62 ± 0.15, girls 0.63 ± 0.18; T/E ratio (mm/mm), boys 0.58 ± 0.13, girls 0.59 ± 0.16; and BMI (kg/m²), boys 17.1 ± 2.4, girls 16.9 ± 2.2. Second order partial correlations, controlling for age and the BMI or age and sum of skinfolds, between birth weight and the skinfold ratios are, respectively, ?0.22 and ?0.20 (p<0.01) for S/T and ?0.29 and ?032 (p<0.01) for T/E in girls, and ?0.18 and ?0.17 (p<0.05) for S/T and ?0.06 and ?0.6 for T/E in boys. Though low, the correlations suggest that as birth weight decreases proportionally more subcutaneous fat is accumulated on the trunk than on the extremities, more so in females than in males. Results of stepwise multiple regression analyses indicate that birth weight accounts for from 2% to 8% of the variance in relative subcutaneous fat distribution at school age.     

Working Capacity of Normal Children Tested on a Bicycle Ergometer

Working capacity defined as that work load performed at a minute pulse rate of 170 was determined in 200 school children aged 6 to 16 and in 40 young adults. Working capacity increased gradually with age and was greater in boys than girls at all ages. The range of normal was large. Working capacities of 11- and 12-year-old Winnipeg children in kg./M./min. were 384 for boys and 300 for girls, these values being 19 and 14% below comparable studies from California and Sweden. Working capacities of Winnipeg student nurses averaged 478 kg./M./min., half the value reported for nurses from Sweden.