• Biomolecules & Therapeutics
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• v.16 no.2
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• pp.141-146
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• 2008

Imbalance in calcium and phosphorous metabolism due to aging or menopause leads to osteoporosis. In contrast to patients with normal blood pressure, hypertensive patients have a higher loss of calcium in the urine with its attendant risk of osteoporosis. The high blood pressure is associated with the risk of bone loss and abnormalities in calcium metabolism leading to calcium loss. So we retrospectively investigated the changes of bone mineral density (BMD) which drugs can have clinical influences over osteoporosis treatments of patients with calcium-antagonists as common antihypertensive drugs and with bisphosphonates which causes a most effective inhibition of osteoclasts resorption. As a result over 70 years of age group and within bisphosphonates group, alendronate 70 mg once-weekly group showed significant increase of BMD in lumbar area. Combination group of cilnidipine and $maxmarvil^{(R)}$ showed very significant decrease of BMD. In conclusion, it is desirable that combination therapy with calcium-antagonists is used carefully in the treatment of osteoporosis with high blood pressure.

• Clinical and Experimental Reproductive Medicine
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• v.23 no.3
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• pp.357-366
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• 1996

The present experiments aimed to investigate the metabolism of calcium during oocyte maturation in rat. The concentration of free calcium and calmodulin in oocytes was measured respectively by using of fluo-3/AM and FITC with microscope fluorescence spectrometer. The ultrastructural localization of calcium precipitates in oocytes was observed with the transmission electron microscope. Cumulus-free immature oocytes(GV-oocyte) were cultured in vitro through 15 hours. The free calcium concentration in GV oocyte was $55.9{\pm}3.5nM$. In calcium-containing medium, the free calcium concentration was increased in germinal vesicle breakdown(GVBD) oocyte($64.2{\pm}7.3nM$). In normal medium after calcium chelator treatment ($10{\mu}M$ BAPTA/AM), the free calcium contents were slightly lower than those in control group. In calcium-free medium, the free calcium content was drastically increased in GVBD($72.7{\pm}3.4nM$) and metaphase I - anaphase I ($88.0{\pm}3.4nM$) oocyte. In maturation rate of oocytes, GVBD rate was high in control group($82.9{\pm}6.55%$) and calcium chelator treatment group($91.2{\pm}4.4%$), but in calcium-free medium group, it was low and then the oocyte was degenerated without polar body formation. Relative content of calmodulin in oocyte was significantly(P<0.001) increased in metaphase I - anaphase I than in GV and GVBD oocyte. The calcium precipitates were observed in mitochondria and cytoplasm of GV oocyte but that were not observed in mitochondria of GVBD and metaphase I - anaphase I oocyte. And then the calcium precipitates reappeared in mitochondria of metaphase II oocyte. The above results indicate that changes in free calcium and calmodulin concentration of oocyte occur according to the maturational stages and the extracellular calcium is required during oocyte maturation. Also change of calcium localization in oocyte occurs according to the maturational stages.

• Horticultural Science & Technology
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• v.34 no.6
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• pp.898-911
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• 2016

Sugars play many important roles in plant metabolism and directly influence fruit quality. The effects of two edible coatings, 2% calcium chloride and 1% pullulan, on sugar metabolism in postharvest Huangguan pear fruit were investigated during cold storage. The respiration rate, sugar content and composition, sucrose metabolism enzyme activities [acid invertase (AIV), neutral invertase (NI), sucrose synthase (SS), and sucrose phosphate synthase (SPS)] and expression of the AIV gene were analyzed during storage at $0^{\circ}C$ for 210 days. Coating treatments slowed the decrease of sucrose and hexose, the respiration rate, and the activities of AIV, NI, SS and SPS, thus maintaining high total soluble solids (TSS) and titratable acid (TA) contents in the fruit. There were no significant differences in AIV expression or activity between the treated and control groups of fruits. Both of the coatings could inhibit the activities of sucrose-cleaving enzymes, thus slowing the decrease of sugar content and maintaining high fruit quality during cold storage.

• Journal of Nutrition and Health
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• v.32 no.2
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• pp.150-157
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• 1999

This study explored the effects of dietary calcium levels and/or ovariectomy on bone formation, bone composition and calcium metabolism using female Sprague-Dawley weanling rats(mean body weight$\pm$SEM : 232.3$\pm$6.7g) as a model. Rats received high(1.5%) calcium diets for eight weeks during the growth period and were randomly assigned to ovariectomy and sham groups. The two groups were than each randomly divided into three sub-groups and fed 0.1%, 0.5% and 1.5% calcium diets for eight weeks after operation. The results indicate that body weight gain was higher in ovariectomy groups than sham groups regardless of dietary calcium levels and food intakes. Serum Ca concentration was decreased in low Ca groups after operation and serum P concentration increased in ovariectomy groups. Serum Ca concentration was decreased in low Ca groups after operation and serum P concentration increased in ovariectomy groups. Serum alkaline phosphatase activity was increased in ovariectomy groups and was not influenced by dietary calcium levels after operation. Urinary hydroxyproline decreased in high Ca intake groups regardless of whether rats had received an ovariectomy or not. The weight, length and breaking force of the femur were not significantly different in all groups. Ash, calcium, phosphate and magnesium contents in the femur and lumbar were not significantly different regardless of ovariectomy operation and dietary calcium levels. But high/normal calcium intake after ovariectomy and sham operation increased the weight and calcium content in bone. Therefore, high calcium intake influenced the formation of peak bone mass during the growth period and calcium levels and calcium levels and calcium levels continued to influence bone growth and composition after ovariectomy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.895-900
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• 1999

We have examined the effects of mayonnaise on the lipid metabolism and calcium bioavailability of rats by using myonnaise. Sprague Dawley male rats(131$\pm$5g) were divided into four dietary groups[Control (Con, 10% soybean oil), Mayonnaise(M5), 10% Mayonnaise(M10)and 15% Mayonnaise(M15)] were fed ad libitum with experimental diets for four weeks. Final body weight exhibited a decrease in the M10 group, also final thymus organ weight showed a significant decreasing trend(p<0.05). The levels of serum, liver and adipose total lipid were significantly different among the four experimental groups(p<0.05). Serum calcium levels were significantly lower in the M15 group than in among the groups(p<0.05). On the other hand, the elevation of serum cholesterol levels were not clearly observed, but triglyceride levels were elevated the M5 and M15 group. The P/S ratio of adipose tissue were higher in the M10 group(2.35$\pm$0.35) than any other groups. Free EDTA in mayonnaise was 0.0307~0.0387%, moisture 12.46~16.49% and calcium 0.012~0.019%. But commercial mayonnaise contained free EDTA higher than the safe use (0.0075%). Safety problems of EDTA additives resulted from mass processed mayonnaise are arising. Though the evaluation of safety can not reach a conclusion with only one or two clinical case studies. It often simply jumps to conclusion. Therefore more wide ranged discussion and deepened study is required to search for the solution of safety problems.

• Journal of Nutrition and Health
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• v.31 no.3
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• pp.279-288
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• 1998

This study explored the effect of calcium levels and/or ovariectomy on bone metabolism using female Sprague-Dawley weanling rats as a model . Rats received a low (0.1%) calcium diet for 8 weeks. The rats were then divided into three subgroups that were fed 0.1% ,0.5% and 1.5% calcium diets for 8 weeks after operation. The results of this experiment indicate that body weight gin was higher in ovariectomy groups than in sham groups regardless of calcium level and food intake. Serum Ca and P concentrations were of normal level regardless of calcium level and ovariectomy. Estrogen concentration was low in the ovariectomized group. Serum alkaline phophatase activity and urinary hydroxyproline have been used as markers of bone formation and resorption. These values were increased in ovariectomized groups. The weight, length and breaking force of femur were not significantly different between the groups. Ash, Ca, P and total lipid contents in femur and lumbar were decreased in the groups fed low calcium . Mg content was decreased in the ovariectomy and total protein content was not affected by calcium level and ovariectomy. The effect groups of ovarectomy on calcium contents of bone was more prominent in lumbar than in femur. In conclusion, though low calcium intakes during growth period may retard the attainment of peak bone mass, calcium supplementation after this period increased bone growth and mineral contents, but not significant effect in three calcium levels. Furthermore, calcium intake was shown to have a greater influence on the mineral contents of femur than of lumbar, and removal of endogenous estrogen production by ovariectomy was shown to be more deleterious on the ash and calcium contents of the lumbar than of femur.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.865.2-865.2
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• 1999

• Development and Reproduction
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• v.7 no.2
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• pp.95-103
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• 2003

Intracellular calcium is an important physiological factor in most cells, and ruthenium red and ryanodine play an important role as calcium modulators. Ruthenium red inhibits calcium-induced calcium release(CICR) from the intracellular calcium store. Ryanodine activates calcium release through ryanodine channel. The present experiment was performed to investigate the effects of two modulators on calcium ion metabolism and to determine their dose-dependency in oocyte and early embryo of mouse. Intracellular calcium ion concentration was measured in realtime by using confocal laser scanning microscope(CLSM) after loading of Fluo-3/AM in mouse oocytes and early embryos. Ruthenium red decreased intracellular calcium ion concentration in oocytes and early embryos at its high concentration(30, 300 $\mu$M). Ryanodine increased intracellular calcium ion concentration in oocytes and early embryos in low concentration(0.01 $\mu$M) but decreased that at higher concentrations(1, 10 $\mu$M). These results indicate that two modulators affected calcium ion metabolism in oocyte and early embryo of mouse, and their dose-dependency was different from somatic cell including myocytes.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.3
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• pp.295-305
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• 1996

This study was done to evaluate the effectiveness of dietary calcium level(a diet which met 100% or twice the calcium level in AIN-76 diet) on preventing bone loss in ovariectomized rats. Forty female Sprauge-Dawley rats(body weight 200$\pm$5g) were divided into two groups. One group were ovariectomized(Ovx) while the others received sham operation(Sham). Thereafter, each rat group was further divided into normal calcium diet(NCD, 0.52%) and high calcium diet(HCD, 1.04%) sub-groups. All rats were fed on experimental diet and deionized water ad libitum for 8 weeks. Urinary pyridinoline & creatinine and serum estradiol, luteinizing hormone, calcium, phosphate, total protein, albumin, alkaline phosphatase and osteocalcin were determined. There were no significant differences in serum calcium. total protein and albumin in the two groups(Ovx vs Sham) of rats. Ovariectomized rats had significantly lower estradiol than sham operated rats. There was a highly significant correlation between total bone mineral density(TBMD) and overall level of esteradiol(r=0.59, p<0.05). Total bone mineral density did not correlate significantly with ALP or osteocalcin, although a negative trend was evident. However, the rats fed high calcium diet had a lower crosslinks value and osteocalcine than the rats fed normal calcium diet. An increased rate of bone turnover is usually associated with a decrease in bone mass bexause bone formation at each remodeling site is never as great as resorption. Ovariectomized rats fed high calcium diet had a lower crosslink value and osteocalcin; it means high cacium diet decreased bone turnover rate. The findings from the present study demonstrated that bone loss due to ovarian hormonal deficiency can be partially prevented by a high calcium diet. Futhermore, these findings support the strategy of the use of a high calcium diet in the prevention of estrogen depletion bone loss (postmenopausal osteoporosis).

• Clinical and Experimental Pediatrics
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• v.58 no.4
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• pp.148-153
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• 2015

The calcium sensing receptor (CaSR) plays an important role in calcium homeostasis. Activating mutations of CaSR cause autosomal dominant hypocalcemia by affecting parathyroid hormone secretion in parathyroid gland and calcium resorption in kidney. They can also cause a type 5 Bartter syndrome by inhibiting the apical potassium channel in the thick ascending limb of the loop of Henle in the kidney. This study presents a patient who had autosomal dominant hypocalcemia with Bartter syndrome due to an activating mutation Y829C in the transmembrane domain of the CaSR. Symptoms of hypocalcemia occurred 12 days after birth and medication was started immediately. Medullary nephrocalcinosis and basal ganglia calcification were found at 7 years old and at 17 years old. Three hypercalcemic episodes occurred, one at 14 years old and two at 17 years old. The Bartter syndrome was not severe while the serum calcium concentration was controlled, but during hypercalcemic periods, the symptoms of Bartter syndrome were aggravated.