Effects of milk powder intervention on bone mineral density and indicators related to bone metabolism in Chinese adolescents.

The study is to determine the effects of milk powder on bone density and metabolism in healthy adolescents. Vitamin D and calcium supplements increased IGF-1 but did not affect bone mineralization or turnover. Higher vitamin D in combination with sufficient calcium supplementation in such populations requires attention. INTRODUCTION: Both calcium and vitamin D play an important role in bone mineralization in adolescents. METHODS: In this one and a half-year randomized controlled trial, 232 participants (aged 12-15 years) were randomly assigned to three intervention groups receiving milk powder fortified with vitamin D 400 IU plus calcium 300, or 600, or 900 mg [Ca3D (n = 54), Ca6D (n = 56), and Ca9D (n = 49)], or one control group maintaining habitual diet [control (n = 73)]. Bone turnover markers, serum intact PTH, 25(OH)D, and IGF-1 levels were measured at baseline and one and a half years, and bone mineral contents and bone areal mineral density were measured by Dual-energy X-ray absorptiometry (DXA) at baseline, one year, and one and a half years. RESULTS: Baseline average serum 25(OH)D level and calcium intake were 29.4 nmol/L and 363.5 mg/day, respectively. There was a significant increase in bone turnover, total body, hip, lumbar spine bone mineral density (BMD), and total body BMC as well as slight fluctuations in 25(OH)D levels over one and a half years without between-group differences. Significantly decreased serum PTH level was only observed in the Ca6D group (31%, p < 0.0001), in which the intervention effect was also significant (p = 0.0029) compared with the control group. IGF-1 levels increased significantly in all intervention groups (18.5 to 22.8%, p < 0.05) but decreased in the control group (16.5%, p < 0.05), and the group by time interaction was also significant (p = 0.0029). CONCLUSIONS: Our study showed that in healthy adolescents with low vitamin D status and calcium intake, mild vitamin D and mild to modest calcium supplements increased IGF-1 but did not affect bone mineralization or turnover. Higher vitamin D in combination with sufficient calcium supplementation in such populations requires attention.

[The vitamin D nutritional status in Chinese urban women of child-bearing age from 2010 to 2012].

Objective: To evaluate the vitamin D nutritional status in Chinese women of child-bearing age by analyzing serum 25-hydroxyvitamin D level in 2010-2012. Methods: Data were obtained from the China Nutrition and Health Survey in 2010-2012. Using cluster sampling and proportional stratified random sampling, 1 514 women of child-bearing age (18-44 years old) from 34 metropolis and 41 small and medium-sized cities were included in this study. Demographic information was collected by questionnaire and serum 25-hydroxyvitamin D concentration was determined by radioimmunoassay, in accordance with the 2010 Institute of Medicine of the National Academies standards. We compared differences in vitamin D levels, specifically serious deficiency, lack of deficiency, insufficiency, and excess. Results: The overall serum 25-hydroxyvitamin D level of Chinese urban women of child-bearing age (P(50) (P(25)-P(75))) was 20.1 (15.1-26.3) ng/ml; minorities had a significantly higher serum 25-hydroxyvitamin D level of 22.0 (15.9-27.5) ng/ml compared with women of Han nationality (19.8 (14.9-26.2) ng/ml) (χ(2)=7.02, P=0.008). The proportions of women with serious deficiency, lack of deficiency, insufficiency, and excess vitamin D were 11.6% (n=175), 37.9% (n=574), 35.1% (n=531), and 0.3% (n=5), respectively. Only 15.1% (n=229) of women of child-bearing age had normal vitamin D nutritional status. No significant differences in vitamin D nutritional status were observed according to age, body mass index, city, nationality, educational level, marital status, or household income per capita (P>0.05). Conclusion: Most Chinese urban women of child-bearing age have poor vitamin D levels and require vitamin D supplementation.

Protein and mRNA expression of follicle-stimulating hormone receptor and luteinizing hormone receptor during the oestrus in the yak (Bos grunniens).

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) have a central role in follicle growth, maturation and oestrus, but no clear pathway in the seasonal oestrus of yak (Bos grunniens) has been found. To better understand the role of FSH and LH in seasonal oestrus in the yak, six yaks were slaughtered while in oestrus, and the pineal gland, hypothalamus, pituitary gland, and gonads were collected. Using real-time PCR and immunohistochemical assays, we determined the mRNA and protein expression of the FSH and LH receptors (FSHR and LHR) in these organs. The analysis showed that the FSHR mRNA expression level was higher in the pituitary gland tissue compared with LHR (p < .01) during oestrus. By contrast, there was low expression of FSHR and LHR mRNA in the pineal gland and hypothalamus. FSHR mRNA expression was higher than that of LHR (p < .05) in the ovary, whereas LHR mRNA expression was higher than that of FSHR (p < .01) in the uterus. FSHR and LHR proteins were located in the pinealocyte, synaptic ribbon and synaptic spherules of the pineal gland and that FSH and LH interact via nerve fibres. In the hypothalamus, FSHR and LHR proteins were located in the magnocellular neurons and parvocellular neurons. FSHR and LHR proteins were localized in acidophilic cells and basophilic cells in the pituitary gland, and in surface epithelium, stromal cell and gland epithelium in the uterus. In the ovary, FSHR and LHR protein were present in the ovarian follicle. Thus, we concluded that FSHR and LHR are located in the pineal gland, hypothalamus, pituitary and gonad during oestrus in the yak. However, FSHR was mainly expressed in the pituitary gland and ovaries, whereas LHR was mainly expressed in the pituitary gland and uterus.

[Optimization of the preparing process for sinitang drop pills by orthogonal test].

The preparing process for Sinitang drop pills was optimized by orthogonal test. The results from nine experiments were subjected with three indexes to objective analysis and variance analysis, and an optimum preparing process for Sinitang drop pills was sieved out. The quality of the drop pills prepared in this way was examined to be up to the standard.

Penicillamine: pharmacokinetics and differential effects on zinc and copper status in chicks.

The pharmacokinetics of D(-)-penicillamine (PA) and the effects of PA on the nutritional status of Cu and Zn in chicks were studied. When administered by subcutaneous or intravenous injection, PA was eliminated from the plasma with biphasic kinetics: i.e., a fast (halftime: 6-7 min) and a slow (halftime: 52-55 min) component. The elimination of PA from the liver or pancreas showed only the slow (halftime: 42-46 min) component. When PA was administered orally, plasma PA concentrations responded over time in bimodal pattern, but the maximal level was only one-fifth that achieved by injection. The subcutaneous injection of PA elicited differential, transient changes in the concentrations of Zn and Cu in the plasma: plasma Zn concentration was decreased, and plasma Cu concentration was increased. Analyses of urine collected from ureter-cannulated chicks showed that PA was rapidly excreted via that route, and that urinary PA excretion was associated with increased urinary excretion of both Zn and Cu. These results show that PA treatment can alter tissue distributions particularly of Zn and, to a lesser extent, of Cu. J. Nutr.

Excess dietary zinc decreases tissue alpha-tocopherol in chicks.

Experiments were conducted to determine the basis of the reduction in tissue alpha-tocopherol concentrations by excess dietary zinc (Zn) in chicks fed purified diets. These reductions were preceded by elevations in the Zn concentrations of plasma and pancreas, and in the amylase activity of plasma and by reductions of exportable enzymes of the pancreas. Chicks fed similar levels of Zn as supplements to a non-purified diet showed no such impairments in either exocrine pancreatic function or tissue alpha-tocopherol concentrations. Depression of feed intake and subsequent changes of concentrations of tissue lipid components by excess dietary Zn accounted for only a minor portion of the reduction of tissue alpha-tocopherol concentrations. Tissue alpha-tocopherol concentrations were moderately correlated with tissue lipid concentrations. The rate of appearance of radioactivity from an oral dose of all-rac-alpha-tocopherol-[3,4-3H]2 in plasma was reduced by 64% by addition of 500 mg Zn/kg to the purified diet for 2 wk. These results indicate that impaired enteric absorption and/or transport of vitamin E as a consequence of Zn-induced pancreatic insufficiency is a major cause of reduced tissue concentrations of alpha-tocopherol produced by excess dietary Zn.