Association between early onset of menarche and anthropometry measurements among adolescent girls in China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the association between early menarche with anthropometry measurements among adolescent girls in China.</p><p><b>METHODS</b>Research material was selected from the data of 2010 Chinese National Surveys on Students Constitution and Health. Probability unit regression method was used to calculate the age of 10th percentile (P 10) at menarche and menarche age before the P 10 was defined as early menarche(9.0-11.6 years old). A total of 1072 girls with early menarche were screened. Each girl with early menarche was frequency matched with two girls who hadn't achieved menarche and with the age difference less than 0.1 yr and from the same urban or rural locations. A total of 2144 girls without menarche were screened. Participants' data of height, weight, sitting height, chest circumference, body mass index(BMI) and height and sitting height index were analyzed. t test and wilcoxon test were used to analyze the anthropometry measurements differences between the two groups, Chi square test was used to analyze the differences of overweight and obesity between the two groups. Multilevel model was used to explore the association between early menarche with anthropometry measurements and overweight and obesity.</p><p><b>RESULTS</b>A total of 1072 girls with early menarche and 2144 girls without menarche. Early menarche girls' height, sitting height, chest circumference, weight and BMI were (151.42 ± 7.46) cm, (80.86 ± 4.21) cm, (73.88 ± 7.72) cm, (44.32 ± 9.35) kg, and (19.18 ± 3.03) kg/m(2), while they were (144.86 ± 7.55) cm, (76.96 ± 4.05) cm, (67.25 ± 6.94) cm, (36.07 ± 7.88) kg and (16.64 ± 2.48) kg/m(2) in girls without menarche. The difference between two groups were significant(Z values were -22.20, -23.69, -24.38, -23.12, -20.17, -6.33 respectively with all P values < 0.01). Multilevel analysis results showed that in 9.0-11.6 years old girls early menarche was associated with anthropometry measurements(all P values < 0.05). Compared with girls without menarche, girls with early menarche had a relative higher height, sitting height, weight, chest circumference, with increments of 5.28 cm, 3.37 cm, 5.53 cm, 6.37 kg, 1.79 kg/m(2). Within subgroup analysis, there were parabolic trends with age in the height, weight and sitting height differences and "U" trend in chest circumference difference between girls with early menarche and girls without menarche.In 9.0-10.8 years old, 10.9-11.0 years old and 11.1-11.2 years old groups, the risk of overweight and obesity among girls with early menarche were 2.98 (95%CI:1.92-4.63) times, 6.76 (95%CI:2.79-16.39) times, 2.99 (95%CI:1.40-6.40) times of girls without menarche.</p><p><b>CONCLUSION</b>The early onset of menarche is related with height, sitting height, weight and chest circumference, and it is closely associated with overweight and obesity among adolescent girls in China.</p>

Protective effect of grape seed proanthocyanidin on spermatogenesis following testicular torsion/detorsion in mice / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the protective effect of grape seed proanthocyanidin (GSP) on spermatogenesis following testicular torsion/detorsion in mice.</p><p><b>METHODS</b>Twenty-four healthy male Kunming mice, aged 8 weeks and weighing 25 - 27 g, were randomly divided into a control, a torsion and a treatment group, each containing 8 animals. The unilateral testicular torsion/detorsion model was established in the treatment and torsion groups. Thirty minutes before detorsion, the animals of the treatment group were injected intraperitoneally with 50 mg/kg GSP, and those of the torsion group with normal saline at the same dose, both for 3 days postoperatively. On the 4th day after surgery, ipsilateral orchiectomy were performed to detect histopathological changes, the levels of superoxide dismutase (SOD) and malondialdehyde (MDA), and the apoptotic index (AI) of germ cells in all the mice.</p><p><b>RESULTS</b>Compared with the torsion group, the treated mice showed significantly increased Johnsen score (5.00 +/- 1.85 vs 7.38 +/- 0.92, P < 0.05), seminiferous tubule diameter ([176.50 +/- 1.60]microm vs [178.75 +/- 1.58] microm, P > 0.05), spermatogenic cell layers (3.75 +/- 1.03 vs 5.75 +/- 0.71, P < 0.05) and SOD activity ([29.04 +/- 4.46] U/mg prot vs [52.67 +/- 3.57] U/mg prot, P < 0.05), but remarkably reduced level of MDA ([4.63 +/- 0.05] nmol/mg prot vs [2.91 +/- 0.04] nmol/mg prot, P < 0.05) and AI of germ cells ([40.50 +/- 1.60]% vs [16.25 +/- 1.67] %, P < 0.05).</p><p><b>CONCLUSION</b>Grape seed proanthocyanidin has a protective effect against spermatogenic injury in mice, the mechanisms of which may be related to its actions of scavenging oxygen free radicals, inhibiting lipid peroxidation and improving the antioxidant ability of the body.</p>