Association between abdominal obesity and blood pressure among 7 to 10 years old Chinese children / 中华预防医学杂志

<p><b>OBJECTIVE</b>To analyze the association between abdominal obesity and blood pressure among 7-10 years old Chinese children.</p><p><b>METHODS</b>A total of 40 495 children aged 7-10 years with complete height, weight, waist circumference and blood pressure data were chosen from the data of 2010 Chinese National Survey on Students Constitution and Health. Based on the "Reference Norms for Screening Overweight and Obesity in Chinese Children and Adolescents" developed by Working Group Obesity in China (WGOC) and the waist to height ratio reference value for children (WHtR ≤ 0.46) , the children were divided into 4 body types (normal weight, simple abdominal obesity, combined obesity and other types). High blood pressure was defined as the systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) higher than the P 95 blood pressure value of 2010 national student of the same gender and age. The prevalence of simple abdominal obesity, combined obesity and high blood pressure were described. Three groups (with 2165 children in each) of children with normal weight, simple abdominal obesity, combined obesity respectively were selected from the chosen ones matched by gender, age (within ± 0.5 years old) and height (within ± 0.3 cm) at the ratio of 1: 1: 1. The value of blood pressure and prevalence of high blood pressure were described.χ(2) test, analysis of variance and multilevel models were used to analyze the relationship between obesity and blood pressure.</p><p><b>RESULTS</b>A total of 40 475 children were selected from the database, including 20 175 boys and 20 320 girls. The prevalence of simple abdominal obesity was 6.36% (2576/40 495), the prevalence of boys and girls was 7.41% (1494/20 175) and 5.32% (1082/20 320) respectively. The prevalence of combined obesity was 16.33% (6611/40 495), the prevalence of boys and girls was 21.30% (4298/20 175) and 11.38% (2313/20 320) respectively. There were statistical differences in the body type distribution of both boys and girls (χ(2) = 869.01, P < 0.01). The prevalence of high blood pressure was 9.62% (3896/40 495), the prevalence of boys (10.05% (2028/20 175)) was higher than girls (9.19% (1868/20 320)) (χ(2) = 8.59, P < 0.01). The value of SBP and DBP among combined obesity group (boys: (103.8 ± 11.3), (64.7 ± 10.1) mm Hg (1 mm Hg = 0.133 kPa); girls: (102.9 ± 12.1), (64.5 ± 10.0) mm Hg) > simple abdominal obesity group (boys: (99.5 ± 11.2), (61.6 ± 9.9) mm Hg; girls: (99.6 ± 11.4), (62.6 ± 9.3) mm Hg)> normal weight group (boys: (97.4 ± 10.8), (60.5 ± 9.4) mm Hg; girls: (97.2 ± 10.8), (60.8 ± 9.4) mm Hg), and the differences were statistical significant (Fboys: 113.22, 62.05; Fgirls: 54.19, 32.31, P < 0.01). According to the results of multilevel model, among boys, compared with the normal weight group, the SBP of combined obesity group and simple abdominal obesity group was 6.0 and 1.8 mm Hg higher respectively (Wald χ(2): 17.55, 204.94, P < 0.01); the DBP was 4.0 and 0.9 mm Hg higher respectively (Wald χ(2): 6.37, 114.05, P < 0.05). Among girls, the SBP was 5.0 and 2.1 mm Hg higher respectively (Wald χ(2):16.47, 92.52, P < 0.01); the DBP was 3.5 and 1.6 mm Hg higher respectively (Wald χ(2): 12.29, 57.52, P < 0.01). Comparing with normal group, the risk of high SBP among boys with simple abdominal obesity was higher (OR = 1.48; 95%CI: 1.06-2.06), and both the boys (SBP: OR = 3.06; 95%CI: 2.28-4.11) ; DBP: OR = 2.72; 95%CI: 1.99-3.72) and girls (SBP: OR = 2.48; 95%CI: 1.75-3.53; DBP: OR = 2.64; 95%CI: 1.82-3.93) in combined obesity group had a higher risk of high SBP and high DBP.</p><p><b>CONCLUSION</b>Simple abdominal obesity is associated with the increasing of blood pressure in children, and combined obesity has a closer ties than simple abdominal obesity.</p>

Analysis of influencing factors on physical endurance of Chinese primary and middle school students aged 10 to 17 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the influencing factors on physical endurance among Chinese primary and middle school students aged 10-17.</p><p><b>METHODS</b>Data was used from "2010 National Physical Fitness and Health Surveillance", from which 68 458 primary and middle school students with complete information were selected. Good physical endurance was defined as endurance running time ≤ P 25 of same gender and age, poor physical endurance as ≥ P 75 of same gender and age. Difference of endurance running time in different physical endurance groups was compared; chi-square test, logistic regression and multiple level model were used to analyze influence of region, BMI, diet, exercise and exercise willingness on physical endurance.</p><p><b>RESULTS</b>There were 34 293 (50.0%) students of good physical endurance and 34 219 (50.0%) ones of poor physical endurance in 68 458 subjects. Percentage of good physical endurance was 53.8% (18 285/33 996) in rural students, higher than urban ones (46.3% (15 954/34 462)) (χ(2) = 384.16, P < 0.01). Percentage of good physical endurance was 12.2% (448/3660) in obese students, lower than normal (55.2% (28 183/51 028)), overweight (29.3% (2012/6874)) and emaciated ones (52.1% (3596/6896)) (χ(2) = 3840.08, P < 0.01). Percentage of good physical endurance was 52.5% (25 534/48 679) in students having breakfast everyday, higher than ones never having breakfast or 1-2 times per week (41.3% (3209/7768))(χ(2) = 438.31, P < 0.01). Percentage of good physical endurance was 51.7% (11 580/22 379) in students having milk everyday, slightly higher than ones never or sometimes having milk (49.2% (22 659/46 079)) (χ(2) = 39.84, P < 0.01). Percentage of good physical endurance was 55.3% (18 961/34 314) in students with adequate physical education class, higher than ones with inadequate class (44.7% (15 278/34 144)) (χ(2) = 756.41, P < 0.01). Percentage of good physical endurance was 58.6% (9484/16 195) in students with one hour exercise or more per day, higher than ones with less than one hour exercise (47.4% (24 755/52 263)) (χ(2) = 619.82, P < 0.01). Percentage of good physical endurance was 60.1% (19 287/32 118) in students who were "very willing" to take part in endurance running, higher than "generally willing" ones (45.4% (10 569/23 272)) and "not willing" ones (33.5% (4383/13 068)) (χ(2) = 2909.61, P < 0.01). Multiple level analysis revealed that risk of poor physical endurance was lower in rural students (OR = 0.80, 95%CI: 0.77-0.82) than urban ones. Risk in emaciated students (OR = 1.11, 95%CI: 1.05-1.17), overweight students (OR = 2.69, 95%CI: 2.55-2.85) and obese students (OR = 7.71, 95%CI: 6.97-8.52) was higher than normal ones. Concerning diet, risk of poor physical endurance in students never having breakfast or once to twice per week was highest (OR = 1.20, 95%CI: 1.13-1.26), followed by students having breakfast three to five times per week (OR = 1.13, 95%CI: 1.08-1.18); risk in students having one bag of milk per day was higher (OR = 1.09, 95%CI: 1.02-1.17) than ones having two bags. Concerning exercise, risk of poor physical endurance in students with inadequate physical education class (OR = 1.20, 95%CI: 1.13-1.26) and less than one hour exercise per day (OR = 1.34, 95%CI: 1.29-1.40) was higher than ones with adequate physical education class and one hour exercise or more respectively. Risk of poor physical endurance in students who were "generally willing" (OR = 1.67, 95%CI: 1.61-1.73) and "not willing" (OR = 2.72, 95%CI: 2.60-2.85) to take part in endurance running was higher than "very willing" ones.</p><p><b>CONCLUSION</b>Urban and rural residence, BMI, breakfast, milk, physical education class, exercise time and exercise willingness were related to primary and middle school students'physical endurance.</p>

Association between early menarche and physical fitness among adolescent girls in China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the association between early menarche and physical fitness among adolescent girls in China.</p><p><b>METHODS</b>Research material was selected from the data of "2010 National Physical Fitness and Health Survey". Probability unit regression method was used to calculate the age of 10th percentile at menarche and menarche age before the 10th percentile was defined as early menarche(9.0-11.6 years old). A total of 1072 girls with early menarche were selected. Each girl with early menarche was matched with one girl from the same urban or rural locations who hadn't achieved menarche with the age difference less than 0.1 years. A total of 1072 girls without menarche were selected. Indicators of physical fitness included 50 m running, standing broad jump, 50 m×8 shuttle running and sit-ups. Differences of physical fitness between early menarche and without menarche were analyzed using t test stratified by age and urban/rural area. The multilevel models of single dependent variable and multiple dependent variables were used to analyze association between early menarche and physical fitness.</p><p><b>RESULTS</b>A total of 2144 students were put in this research. Among girls (11.0-11.6 years old) in urban areas, 50 m running, standing broad jump and sit-ups was (9.78 ± 0.85) s, (153.81 ± 18.59) cm, and 27.79 ± 10.25, respectively for those with early menarche, while in girls without menarche was (10.01 ± 0.90) s, (149.71 ± 18.72) cm and 26.28 ± 10.11, respectively. There were significant differences between two groups on all above variables (t values were 4.02, 3.43 and 2.31, respectively with all P values <0.01). Among girls in rural, 50 m×8 shuttle-running and sit-ups was (125.22 ± 15.57) s and 24.96 ± 8.97 for those with early menarche, while it was (120.92 ± 13.06) s and 22.96 ± 9.83 for those without menarche. There were significant differences between two groups on both variables(t values were 3.89 and 2.77 with both P values < 0.01). In addition, 50 m×8 shuttle-running in girls (10.0-10.9 years old) with early menarche was (128.52 ± 15.74) s and it was (123.89 ± 13.50) s in girls without menarche. The difference was significant (t = 2.14, P < 0.05). The multilevel analysis showed that 50 m running, standing broad jump and sit-ups in girls with early menarche was 0.12 s, 3.14 cm and 1.11 higher than girls without menarche (Waldχ(2) values were 4.00, 6.22 and 4.07, respectively with all P values < 0.05). But 50 m×8 shuttle-running in girls with early menarche was 1.95 s less than girls without menarche (Waldχ(2) = 3.96, P < 0.05).</p><p><b>CONCLUSION</b>Early menarche may be associated with higher speed fitness, leg power and muscle power and lower physical stamina.</p>

Interference of octamer-binding transcription factor 4A and its effect on the proliferation and multiple differentiation of human dental pulp cells / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the expression of octamer-binding transcription factor 4A(Oct4A) in human dental pulp cells(DPC)and the effect of Oct4A on the proliferation and multiple differentiation ability of DPC.</p><p><b>METHODS</b>Expression of Oct4A in DPC was detected by realtime quantitative PCR(RT-qPCR). siRNA-Oct4A was constructed and transfected (50 nmol/L) into DPC with Lipofectamine(TM) RNAiMAX for 24, 48, 72, 96 and 120 h. The proliferation rate of DPC was examined using cell counting kit 8 (CCK-8) assay. The alizarin red staining was used to observe the formation of calcification nodules in DPC with 14 d of osteogenic induction, and oil red O staining to observe the formation of lipid droplet in DPC with 14 d of adipogenic induction. The expression of osteogenesis-related genes dentin sialophosphoprotein (DSPP) and adipogenesis-related genes lipoprotein lipase (LPL) was detected using RT-qPCR and Western blotting.</p><p><b>RESULTS</b>The expression of Oct4A reached the peak in P3 DPC (2.10 ± 0.10), which was 2.10 times as much as that in P1 (P = 0.000 vs. P1 and P7), and decreased along passages. The interference efficiency of DPC transfection peaked at 72 h (69.7%). Compared with control group and negative control group (IR-siRNA), the proliferation rate and multiple differentiation ability of DPC in interference group (Oct4A-siRNA) were downregulated (P = 0.000), and DSPP and LPL in DPC from interference group significantly decreased (P = 0.000).</p><p><b>CONCLUSIONS</b>The interference of Oct4A significantly downregulated the cell proliferation rate and multilineage differentiation capability of DPC.</p>