The Experts below are selected from a list of 39414 Experts worldwide ranked by ideXlab platform
Riitta Korpela - One of the best experts on this subject based on the ideXlab platform.
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The effect of Lactobacillus helveticus fermented milk on acute changes in Calcium Metabolism in postmenopausal women
European Journal of Nutrition, 2004Co-Authors: Mirkka Narva, Riikka Nevala, Tuija Poussa, Riitta KorpelaAbstract:Background: Milk fermented with Lactobacillus helveticus ( L. helveticus ) has been shown to lower blood pressure and to increase bone mineral content in spontaneously hypertensive rats. The effect of L.helveticus may be due to better Calcium availability. Aim of the study: In the present study the effect of milk fermented with L. helveticus on acute changes in Calcium Metabolism and bone resorption in postmenopausal women was studied. Methods: The study was performed as a randomised double-blind crossover study of 20 postmenopausal women (mean age 65, range 50–78). The study was carried out in two parts. Firstly, L. helveticus fermented milk was compared to a control milk. Secondly, juice containing peptides formed with L. helveticus bacteria was compared to a control juice. The acute effect on Calcium Metabolism was measured during the study day by serum ionised Calcium (iCa), parathyroid hormone (PTH), Calcium (Ca), phosphate (P), and urinary Calcium. A direct marker of bone turnover, carboxyterminal telopeptide of type I collagen (ICTP), was measured from the serum. Results: L. helveticus fermented milk reduced serum PTH (405.3 ± 37 ng/l vs. 454.9 ± 37, p = 0.012) and increased serum Calcium (19.1 ± 0.2 mmol/l vs. 18.8 ± 0.2, p = 0.031) compared to the control milk. L. helveticus derived peptides had no significant acute effect on Calcium Metabolism, in fact, ionised Calcium was lower and PTH higher after the juice containing peptides compared to the control juice. Conclusions: Fermentation of milk with Lactobacillus helveticus had a positive acute effect on Calcium Metabolism. This effect was not explained by the small peptides formed by L. helveticus .
Hiroyuki Kawashima - One of the best experts on this subject based on the ideXlab platform.
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Vitamin D and Calcium Metabolism in hypertension and vascular smooth muscle cell function
Journal of Bone and Mineral Metabolism, 1991Co-Authors: Hiroyuki KawashimaAbstract:Disturbances in extracellular (systemic) and intracellular Calcium Metabolism have been demonstrated. Intracellular free Calcium in vascular smooth muscle cells is elevated, which is believed to be the final determinant of vascular tone, thus blood pressure. This hypothesis is supported by the fact that Calcium channel blocker reduces blood pressure in hypertension by blocking both receptor-operated and potential-operated Calcium channel. On the other hand, Calcium balance appears to be negative in hypertension and dietary supplement of Calcium has been demonstrated to be effective in reduction of blood pressure in both animals and humans with high blood pressure. The latter observation seems to be opposite to the effect of Calcium channel blocker, since restored Calcium balance may increase intracellular free Calcium concentration by supplying higher amount of extracellular (plasma) Calcium to the cell membmane, which is leaky in hypertension. The effect of dietary Calcium supplement may be explained by changes in Calcium regulating hormones but not Calcium per se . Recent data on Calcium Metabolism in the spontaneously hypertensive rats and effect of vitamin D in vascular smooth muncle cells will be discussed in relation to the regulation of vascular tone and blood pressure.
Yuxiao Yang - One of the best experts on this subject based on the ideXlab platform.
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chronic proton pump inihibitor therapy and Calcium Metabolism
Current Gastroenterology Reports, 2012Co-Authors: Yuxiao YangAbstract:Proton pump inhibitors (PPIs) have been widely used since their introduction in the late 1980s because they are highly effective for acid-related conditions. However, some recent epidemiological studies have suggested a positive association between PPI therapy and the risk of osteoporotic fractures. The potential mechanisms underlying this association may be related to the physiologic effects of chronic acid suppression on Calcium Metabolism. First, chronic hypergastrinemia induced by PPI therapy may lead to parathyroid hyperplasia, resulting in increased loss of Calcium from the bone. Second, profound gastric acid suppression may reduce the bioavailability of Calcium for intestinal absorption. I will review the published evidence regarding these potential links and discuss their clinical implications.
Mirkka Narva - One of the best experts on this subject based on the ideXlab platform.
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The effect of Lactobacillus helveticus fermented milk on acute changes in Calcium Metabolism in postmenopausal women
European Journal of Nutrition, 2004Co-Authors: Mirkka Narva, Riikka Nevala, Tuija Poussa, Riitta KorpelaAbstract:Background: Milk fermented with Lactobacillus helveticus ( L. helveticus ) has been shown to lower blood pressure and to increase bone mineral content in spontaneously hypertensive rats. The effect of L.helveticus may be due to better Calcium availability. Aim of the study: In the present study the effect of milk fermented with L. helveticus on acute changes in Calcium Metabolism and bone resorption in postmenopausal women was studied. Methods: The study was performed as a randomised double-blind crossover study of 20 postmenopausal women (mean age 65, range 50–78). The study was carried out in two parts. Firstly, L. helveticus fermented milk was compared to a control milk. Secondly, juice containing peptides formed with L. helveticus bacteria was compared to a control juice. The acute effect on Calcium Metabolism was measured during the study day by serum ionised Calcium (iCa), parathyroid hormone (PTH), Calcium (Ca), phosphate (P), and urinary Calcium. A direct marker of bone turnover, carboxyterminal telopeptide of type I collagen (ICTP), was measured from the serum. Results: L. helveticus fermented milk reduced serum PTH (405.3 ± 37 ng/l vs. 454.9 ± 37, p = 0.012) and increased serum Calcium (19.1 ± 0.2 mmol/l vs. 18.8 ± 0.2, p = 0.031) compared to the control milk. L. helveticus derived peptides had no significant acute effect on Calcium Metabolism, in fact, ionised Calcium was lower and PTH higher after the juice containing peptides compared to the control juice. Conclusions: Fermentation of milk with Lactobacillus helveticus had a positive acute effect on Calcium Metabolism. This effect was not explained by the small peptides formed by L. helveticus .
Rongqing Zhang - One of the best experts on this subject based on the ideXlab platform.
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cloning and expression of a pivotal Calcium Metabolism regulator calmodulin involved in shell formation from pearl oyster pinctada fucata
Comparative Biochemistry and Physiology B, 2004Co-Authors: Shuo Li, Cen Zhang, Yong Zhang, Mianzhi Gu, Rongqing ZhangAbstract:Abstract The shells of bivalves are mainly composed of Calcium carbonate, a product of Calcium Metabolism. In the process of shell formation, the uptake, transport and recruitment of Calcium ion are highly regulated and involved in many factors. Among these regulatory factors, calmodulin (CaM), a pivotal multifunction regulator of Calcium Metabolism in nearly all organisms, is thought to play an important role in the Calcium Metabolism involved in shell formation. In this study, a full-length CaM cDNA was isolated from the pearl oyster ( Pinctada fucata ). The oyster calmodulin encodes a 16.8 kDa protein which shares high similarity with vertebrate calmodulin. The oyster CaM mRNA shows the highest level of expression in the gill, a key organ involved in Calcium uptake in oyster Calcium Metabolism. In situ hybridization results revealed that oyster CaM mRNA is expressed at the folds and the outer epithelial cells of the dorsal region of the mantle, suggesting that CaM is involved in regulation of Calcium transport and secretion. Oyster CaM also showed a typical Ca 2+ dependent electrophoretic shift characterization and Calcium binding activity. Taken together, we have identified and characterized a pivotal Calcium Metabolism regulator of the oyster that may play an important role in regulation of Calcium uptake, transport and secretion in the process of shell formation.
