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Zhang S.-Q.,National Institute for Nutrition and Health
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2015

Icaritin (ICT), a bioactive metabolite of prenylflavonoids from genus Epimedium, has displayed potential benefits for the treatment of osteoporosis, prostate cancer, liver cancer, renal cancer and breast cancer. To investigate the quantity of ICT in bones in vivo, a simple and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed. After a rapid one-step liquid-liquid extraction using ethyl acetate with recovery more than 87.2% at four levels (0.1, 0.2, 8 and 15ng/mL), ICT and internal standard coumestrol were analyzed on a C18 column using a gradient elution of acetonitrile and water containing ammonium formate and formic acid at a flow rate of 0.3mL/min. Quantification was performed using selected reaction monitoring mode to monitor precursor-product ion transitions of m/z 367.1→297.1 for ICT and of 267.0→211.1 for coumestrol in the negative ionization mode. A calibration curve with good linearity (r>0.99) within the concentration range of 0.1-20ng/mL for ICT was obtained with the lower limit of quantification of 0.1ng/mL. Matrix effect did not interfere with ICT analysis and ICT was stable under three freeze-thaw cycles, short-term temperature, post-preparative and long-term temperature conditions. The method was successfully applied to a dynamic distribution of ICT in mouse bone after a single intraperitoneal administration to ICT to mice. © 2014 Elsevier B.V.

Zhang Y.,U.S. Center for Disease Control and Prevention | Piao W.,National Institute for Nutrition and Health | Ji Y.,Peking University
Journal of Huazhong University of Science and Technology - Medical Science | Year: 2016

Childhood risky behaviors always result in adverse health outcomes. These behaviors are greatly affected by social environment and individual factors. However, few studies explored the social determinants of schoolchildren’s health behaviors. In this cross-sectional study, the social determinants of health behaviors were examined among both migrant and resident students in Beijing, China. Data of 967 children from six urban and suburban primary schools were analyzed using multiple linear regression analysis. The results showed that less than 60% of children performed some healthy behaviors, although their health knowledge was generally good. Children’s health behavior scores were greatly determined by school characteristics, health knowledge, demographic characteristics, and family context. Therefore, improving health education and conditions in primary schools is the priority to promote children’s healthy behaviors, especially for disadvantaged children. © 2016, Huazhong University of Science and Technology and Springer-Verlag Berlin Heidelberg.

Icaritin (ICT), a major component in herb Epimedium brevicornum Maxim., shows beneficial effects for the treatment of osteoporosis and various cancers, and is predominantly metabolized to glucuronidated icaritin (GICT). Although clinical trials of ICT have exhibited good safety and tolerance, the dynamic bioditributions of ICT and GICT have not been reported. In the present study, the chemical structure of GICT was firstly reported, and a reliable ultra-high performance liquid chromatography-tandem mass spectrometry method (UHPLC-MS/MS) was firstly established for the simultaneous quantifications of ICT and GICT in rat tissues. The dynamic distribution of ICT and GICT in rat tissues and their pharmacokinetic parameters have been reported for the first time. ICT, GICT and the internal standard coumestrol were separated on a C18 column with a gradient mobile phase of acetonitrile and water containing ammonium formate and formic acid at a flow rate of 0.3 mL min-1. The analytes were quantified by a triple quadrupole tandem mass spectrometer in the negative ionization mode. The lower limit of quantification values for ICT and GICT were 0.2 and 2 ng mL-1, respectively. Good selectivity, linearity, accuracy, precision and recovery were achieved, and no significant matrix effect was observed. The UHPLC-MS/MS was firstly applied to a dynamic biodistribution study of ICT and GICT in rats, following an intraperitoneal administration of ICT at a dose of 10 mg kg-1. 2016. © The Japan Society for Analytical Chemistry.

Chen X.,National Institute for Nutrition and Health
Journal of Occupational and Environmental Medicine | Year: 2016

OBJECTIVE:: To understand the association of domain-specific physical activity (PA) with leisure-time sedentary behavior (LTSB) among Chinese professionals. METHODS:: Totally, 3326 workers aged 35 to 64 years old from Beijing city and Zhejiang province were asked information on domain-specific PA with a revised Global Physical Activity Questionnaire (GPAQ). The association of domain-specific PA with LTSB-lifestyle (≥4?hours/day spent on LTSB) was examined with a binary logistic regression model. RESULTS:: Compared with sedentary occupational activity (OA), light-, moderate-, and vigorous-intensity OA were respectively associated with 55.3% (ORs, 0.447; 95%CI, 0.378 to 0.529), 63.5% (ORs, 0.365; 95%CI, 0.285 to 0.468), and 77.1% (ORs, 0.229; 95%CI, 0.126 to 0.417) less the odds of having LTSB-lifestyle. Those performing domestic activity (DA) are greater than and equal to 19.6?MET-hours/week had 30.1% (ORs, 0.699; 95%CI, 0.576 to 0.848) less the odds. CONCLUSIONS:: Both non-sedentary occupations and DA were negatively associated with LTSB-lifestyle in these professionals. Copyright © 2016 by the American College of Occupational and Environmental Medicine

Wu F.,University of Tasmania | Wu F.,Anhui Medical University | Laslett L.L.,University of Tasmania | Zhang Q.,National Institute for Nutrition and Health
Journal of Clinical Endocrinology and Metabolism | Year: 2015

Context: There is no consensus on the definition of Vitamin D deficiency for bone health based on serum 25-hydroxyVitamin D (25OHD) levels. Objective: Our objective was to determine whether thresholds exist for associations between 25OHD levels and bone outcomes and if low 25OHD levels have adverse effects on bone health. Design: This is a cross-sectional study. Participants: This study included secondary school students in Beijing, China, aged 12-15 years. Measures:Wemeasured serum 25OHD; bone mineral density (BMD) of total body, hip, and lumbar spine (LS); serum PTH; bone alkaline phosphatase (BAP); and tartrate-resistant acid phosphatase 5b (TRAP5b) in 222 healthy adolescents (111 girls, 111 boys). Results: The prevalence of low 25OHD was 61% (<30 nmol/liter) and 97% (<50 nmol/liter) (mean 25OHD, 30 nmol/liter). Dietary calcium intake was low (294 and 307 mg/d for boys and girls, respectively). In girls, break-points for 25OHD (nmol/liter) were: total body BMD 20 (95% confidence interval [CI], 14-27), hip BMD 25 (17-34), LS BMD 22 (14-30), TRAP5b 37 (22-52), and PTH 31 (23-38). In boys, break-points were: total body BMD 39 (24-55), TRAP5b 33 (20-45), and PTH 35 (27-43); no break-points were identified for hip and LS BMD. No break-points were identified forBAPin either gender.Belowthese break-points, higher25OHDis associated with increased total body BMD, reduced PTH, and TRAP5b, whereas above these break-points, no such relationship exists. Conclusions: Vitamin D deficiency and insufficiency is common in healthy Chinese adolescents. Attaining serum 25OHD levels of more than 20-37 nmol/liter in girls and 33-39 nmol/liter in boys had positive influences on BMD and bone remodelling markers. However, estimates may be affected by low calcium intake and low serum 25OHD levels, with 97% of adolescents having levels below 50 nmol/liter. Copyright © 2015 by the Endocrine Society.

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