Objective To observe the effects of enhanced exercise and combined vitamin D and calcium supplementation on muscular strength and fracture occurrence in postmenopausal women with a high risk of osteoporosis.Methods Totally 614 postmenopausal women at high risk factors of osteoporosis were enrolled in Dongcheng district of Beijing and randomized into four groups:group A(control group,n=173),group B(regular Tai Chi exercise,n=171),group C(calcium 600 mg/d+VitD800 U/d,n=139),and group D[calcium 600 mg/d+25 hydroxyl vitamin D(25OHD) 0.25 μg/d,n=131].Muscular strength was measured at baseline and one and two years after intervention.Bone turnover markers were measured at baseline and during the two-year follow-up.Falls and fractures were recorded.Results The incidence of 25OHD<50 nmol/L was approximately 92.6%.During the follow-up,the left grip strength decreased significantly two years after intervention(t=-3.252,P=0.001)in group A.Right grip strength decreased significantly in group B(t=2.460,P=0.015)while left grip strength improved significantly in group C(t=-2.051,P=0.043)one year after intervention.In group D,muscular strength in both 12-month and 24-month did not change compared with baseline(both P>0.05).Furthermore,serum procollagen type I N-terminal propeptide elevated significantly in group A(t=-2.962,P=0.004),group B(t=-2.888,P=0.005),and group C(t=-2.441,P=0.016),whereas β-C-terminal telopeptide of type I collagen decreased significantly in group B(t=2.285,P=0.024)and group D(t=2.596,P=0.011)two years after intervention.Conclusion Enhanced exercise and combined calcium vitamin D supplementation may help sustain muscle strength in postmenopausal women,while calcium and vitamin D supplementation may improve muscular strength within a short period of time.

Objective To investigate the lead and cadmium contents in different sampling sites from full term neonatal placenta and to explore the role of placental sample in the evaluation of intrauterine heavy metals exposure.Methods The placentas from 30 healthy full term neonates were collected from the West China Second Hospital of Sichuan University during May and June 2016.Each placenta fetal side was divided into the left and right parts with the umbilical vein in the umbilical cord cross-section as the 12 o'clock direction.The villus lobular tissue samples were taken from the 1/4 radius in left part (site A) and 3/4 radius in the right part (site B).The graphite furnace atomic absorption spectrometry was used to detect the lead and cadmium contents in the samples.The elements contents in the site A and B were performed the paired t-test and correlation analysis.Results The mean contents of lead and cadmium in dry weight sample at placental site A were 91.8 and 66.7μg/kg which at the site B were 88.9 and 64.8 μg/kg respectively.The lead and cadmium contents at these two sites presented the positive correlation,the coefficients were 0.98 and 0.97 respectively,whereas the difference in contents between the tissues from different placental sites had no statistical significance.Conclusion The lead and cadmium contents of villus lobular tissue in the central part of placenta fetal side (1/4-3/4 radius area) are basically consistent,which is a reliable indicator for evaluating the intrauterine heavy metals exposure.