• Title/Summary/Keyword: Calcium

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Calcium Signaling of M II Oocyte during Chemical Activation of Calcium Ionopore and Cytochalasin B

  • Kim, Sung-Woo;Park, Jin-Ki;Park, Chun-Gyu;Lee, Ju-Young;Han, Joo-hee;Lee, Seung-Eun;Baek, Kyung-Nye;Chang, Won-Kyung
    • Proceedings of the KSAR Conference
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    • 2004.06a
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    • pp.260-260
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    • 2004
  • The calcium ionophore (A23187) has been used for activation of porcine oocytes from in vitro maturation by many researches. The signaling of calcium was known to be a primary factor of activation of MII oocyte by calcium ionophore. The calcium level was measured by an intensity of fluo 4 fluorescence and confocal microscope. The level was increased by 7% ethanol or 70 μM calcium ionophore but oscillation was not found. (omitted)

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The Role of Milk Products in Metabolic Health and Weight Management

  • Zemel, Michael B.
    • Journal of Dairy Science and Biotechnology
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    • v.28 no.1
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    • pp.17-28
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    • 2010
  • A substantial body of evidence has emerged over the last decade in support of the novel concept that dietary calcium and dairy foods play an important role in regulating energy metabolism and thereby promote healthy weight management and reduce obesity risk. This concept has been demonstrated in experimental animals studies, cross-sectional and prospective population studies and a number of randomized clinical trials. Notably, the effects of dairy foods in weight management are more consistent than the effects of supplemental calcium across clinical trials, and calcium per se is responsible for approximately 40-50% of the effects of dairy. The calcium component is only effective in individuals with chronically low calcium intake, as it serves to prevent the endocrine response to low calcium diets which otherwise favors adipocyte energy storage; calcium also serves to promote energy loss via formation of calcium soaps in the gastrointestinal tract and thereby reduce fat absorption. The calcium-independent anti-obesity bioactivity of dairy resides primarily in whey. The key components identified to date are leucine and bioactive peptides resulting from whey protein digestion. The high concentration of leucine in whey stimulates a repartitioning of dietary energy from adipose tissue to skeletal muscle where it provides the energy required for leucine-stimulated protein synthesis, resulting in increased loss of adipose tissue and preservation of skeletal muscle mass during weight loss. Finally, dairy rich diets suppress the oxidative and inflammatory responses to obesity and thereby attenuate the diabetes and cardiovascular disease risk associated with obesity.

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Modeling of the Parathyroid Hormone Response after Calcium Intake in Healthy Subjects

  • Ahn, Jae Eun;Jeon, Sangil;Lee, Jongtae;Han, Seunghoon;Yim, Dong-Seok
    • The Korean Journal of Physiology and Pharmacology
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    • v.18 no.3
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    • pp.217-223
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    • 2014
  • Plasma ionized calcium ($Ca^{2+}$) concentrations are tightly regulated in the body and maintained within a narrow range; thus it is challenging to quantify calcium absorption under normal physiologic conditions. This study aimed to develop a mechanistic model for the parathyroid hormone (PTH) response after calcium intake and indirectly compare the difference in oral calcium absorption from PTH responses. PTH and $Ca^{2+}$ concentrations were collected from 24 subjects from a clinical trial performed to evaluate the safety and calcium absorption of Geumjin Thermal Water in comparison with calcium carbonate tablets in healthy subjects. Indirect response models (NONMEM Ver. 7.2.0) were fitted to observed $Ca^{2+}$ and PTH data, respectively, in a manner that absorbed but unobserved $Ca^{2+}$ inhibits the secretion of PTH. Without notable changes in $Ca^{2+}$ levels, PTH responses were modeled and used as a marker for the extent of calcium absorption.

Calcium permeability of transient receptor potential canonical (TRPC) 4 channels measured by TRPC4-GCaMP6s

  • Ko, Juyeon;Myeong, Jongyun;Yang, Dongki;So, Insuk
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.1
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    • pp.133-140
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    • 2017
  • Conflicting evidence has been obtained regarding whether transient receptor potential cation channels (TRPC) are store-operated channels (SOCs) or receptor-operated channels (ROCs). Moreover, the Ca/Na permeability ratio differs depending on whether the current-voltage (I-V) curve has a doubly rectifying shape or inward rectifying shape. To investigate the calcium permeability of TRPC4 channels, we attached GCaMP6s to TRPC4 and simultaneously measured the current and calcium signals. A TRPC4 specific activator, (-)-englerin A, induced both current and calcium fluorescence with the similar time course. Muscarinic receptor stimulator, carbachol, also induced both current and calcium fluorescence with the similar time course. By forming heteromers with TRPC4, TRPC1 significantly reduced the inward current with outward rectifying I-V curve, which also caused the decrease of calcium fluorescence intensity. These results suggest that GCaMP6s attached to TRPC4 can detect slight calcium changes near TRPC4 channels. Consequently, TRPC4-GCaMP6s can be a useful tool for testing the calcium permeability of TRPC4 channels.

A Study on Oxalic Acid and Calcium Content in Korean Foods (한국 상용식품중 칼슘과 수산함량에 관한연구)

  • Kim, Eul-Sang;Im, Kyeoung-Ja
    • Journal of Nutrition and Health
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    • v.10 no.4
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    • pp.104-110
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    • 1977
  • Vegetables are liberally taken to enhance the mineral, vitamin, and rouphage value of the diet. And calcium is an essential mineral at all ages, although the daily requirement varies with physiological status of the individual. On the other hand, oxalic acid is an unwanted constituent of several clinical disorders. It is therefore necessary to take into account the calcium as well as the oxalic acid content of the various calcium, foods. Oxalic acid, calcium, calcium/oxalic acid ratio and available calcium have been determined in 31 kinds of the Korean common vegetables. The results are summarized as follows; 1. The highest content of oxalic acid has been recorded in Amaranth. spinach and beet. It is respectively 1,100mg%, 619mg%, 550mg% in fresh sample. It is comparatively high in Leek, leavels of perilla, Mugwort, Chyi-leaves, green red pepper, Burdock. 2. Many vegetables have been calculated as below 2.0 in the calcium/oxalic acid ratio. 3. Avaiable calciumis much in Malaolitoria, Lettuce, Green onion whole, Green garlic, Wild onion, Cabbage and Radish root. 4. A food calendar is suggested as a guide to the proper selection of food items for normal individuals and for those suffering from urolithiasis, cardiovascular disease or calcium deficiency status.

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The Physiological Changes in the Olive Flounder Paralichthys olivaceus Caused by a Diet Containing CaO (CaO (oxide calcium)가 첨가된 사료 공급이 넙치(Paralichthys olivaceus)에 미치는 생리적 변화에 대한 연구)

  • Moon, Hye-Na;Namgung, Jin;Yeo, In-Kyu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.47 no.5
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    • pp.567-576
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    • 2014
  • This study investigated the physiological effects of a diet containing calcium oxide (CaO) on the olive flounder, Paralichthys olivaceus. The results indicate that the amount of calcium in the blood was higher in the calcium group compared with the controls. The aspartate amino transferase (AST) and alanine amino transferase (ALT) levels were lower in the calcium group, while lysozyme activity was higher in the calcium group. Histologically, fish in the calcium group had more hepatocytes in the liver and more intact scales. In addition, an attack experiment using Vibrio anguillarum (KCTC-2711) and Edwardsiella tarda (KCTC-3657) showed that the survival was higher in the calcium group compared with the controls. These results suggest that feeding fish CaO when they require it, such as during periods of gonadal maturation and rapid growth, will increase their immunity and resistance to pathogens.

Effects of Ca, Si on the Microstructure and Aging Characteristic of AZ91 Alloy (AZ91합금의 조직(組織)과 시효특성(時效特性)에 미치는 Ca 및 Si의 영향(影響))

  • Jhee, T.G.;Kim, Y.K.
    • Journal of the Korean Society for Heat Treatment
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    • v.15 no.6
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    • pp.260-268
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    • 2002
  • The effects of calcium and silicon on microstructure and aging characteristics of AZ91 magnesium alloy during T5 treatment was investigated. The addition of 0.88% calcium or 0.25% silicon to AZ91 alloy made dendrite cell smaller. Especially, silicon is more effectively acted as refinement of the dendrite cell than calcium. It is due to that $Mg_2Si$ precipitated at the dendrite cell boundary or in the matrix during T5 treatment of Si added AZ91 alloy retarded the growth of the secondary phase. In the mean while, without inducing the precipitates containing calcium, calcium was segregated mainly around secondary phase such as $Mg_{17}Al_{12}$ and partially dissolved in ternary eutectic (Mg-Al-Ca) structure. In the AZ91 alloy containing both silicon and calcium, more finely distributed $Mg_2Si$ in matrix homogeneously and much finer microstructure were obtained than those containing silicon or calcium. Hence, An AZ91 containing both silicon and calcium was more effective to retarding the growth of the secondary phase than the other AZ91 alloy such as AZ91 alloy containing silicon or AZ91 alloy containing calcium.

Investigation on the Surface Hydrophobicity and Aggregation Kinetics of Human Calprotectin in the Presence of Calcium

  • Yousefi, Reza;Ardestani, Susan K.;Saboury, Ali Akbar;Kariminia, Amina;Zeinali, Madjid;Amani, Mojtaba
    • BMB Reports
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    • v.38 no.4
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    • pp.407-413
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    • 2005
  • Calcium and zinc binding protein, calprotectin is a multifunctional protein with broad spectrum antimicrobial and antitumoural activity. It was purified from human neutrophil, using a two-step ion exchange chromatography. Since surface hydrophobicity of calprotectin may be important in membrane anchoring, membrane penetration, subunits oligomerization and some biological roles of protein, in this study attempted to explore the effect of calcium in physiological range on the calprotectin lipophilicity. Incubation of human calprotectin ($50\;{\mu}g/ml$) with different calcium concentrations showed that 1-anilino-8-naphthalene sulfonic acid (ANS) fluorescence intensity of the protein significantly elevates with calcium in a dose dependent manner, suggesting an increase in calprotectin surface hydrophobicity upon calcium binding. Our study also indicates that calcium at higher concentrations (6, 8 and 10 mM) induces aggregation of human calprotectin. Our finding demonstrates that the starting time and the rate constant of calprotectin aggregation depend on the calcium concentration.

Effect of Caffeine on Coronary Circulation and Calcium Release in Isolated Guinea Pig Hearts (Guinea Pig Heart의 관상동맥 순환기능과 Calcium Release에 있어서 Caffeine이 미치는 영향)

  • 김은지
    • Journal of Nutrition and Health
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    • v.25 no.7
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    • pp.597-607
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    • 1992
  • The present study examined effects of caffeine on coronary circulation myocardial oxygen me-tabolism and calcium release in isolated perfused guinea pig hearts. Intracoronary caffeine({{{{ {10 }^{-5 } }}}}∼{{{{ { 10}^{-3 } }}}}M) was employed for 10 minutes to measure coronary perfusate flow(CF) and coronary vascular sresistance(CVR) at a constant coronary perfusion pressure of 80 cmH2O Perfusate myocardial oxygen consumption(MVO2) and percent oxygen extraction(%EC2) were calcula-ted. In addition calcium contents in both perfusate samples were measured to calculate calcium release in coronary venous effluent. Caffeine significantly decreased CF and increased CVR during 10 minutes of caffeine perfusion regardless of dose of caffeine perfused exhibiting time-response. While % EO2 was significantly enhanced with caffeine MVO2 was markedly reduced. The coronary venous perfusate pH dcreased during the perfusion with caffeine. These changes were consistent with caffeine-induced metabolic acidosis. Calcium release appeared to be dose-dependent and high dose of caffeine greatly increased venous calcium release even 2 minutes after perfusion with carffeine. These finding in dicate that caffeine produced coronary vasoconst-riction with increased calcium release in isolated perfused guinea pig hearts. Additionaly this vasoconstrictor response mignt be due tin part to the direct actions of caffeine.

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Effect of Nutrient Intake on Bone Mineral Density in Postmenopausal Women (폐경후 여성의 골밀도에 대한 영양소 섭취실태의 영향)

  • 이보경
    • Journal of Nutrition and Health
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    • v.25 no.7
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    • pp.642-655
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    • 1992
  • This study was designed to investigate the effect of nutrient intake on bone mineral density (BMD) of the lumbar spine(L2longrightarrowL4) in 41 postmenopausal women. The BMD of the lumbar spine was positively correlated with caiorie protein animal protein fat animal fat calcium animal calcium milk ad dairy calcium phosphorus iron animal iron vitamin A thiamin animal calcium milk and dairy calcium phosphorus iron animal iron vitamin A thiamin riboflavin niacin and ascorbic acid intake. Postmenopausal wmen of BMD$\geq$100% showed enhanced calorie protein fat calcium phosphrous niacin intake compared women of BMD<100% In the group of calorie protein riboflavin intake$\geq$recommended dietary allowances(RDA) BMD was significantly higher than BMD in the group of these nutrient intakes$\geq$700 mg/d is significantly higher than BMD that of examined using stepwise multiple regression analysis. From this analysis in subjects aged 50~59 years fat intake only in subjects aged 60~69 years niacin intake Ca/P in total subjects fat riboflavin intake were signifiant independent predictors of BMD In the group of menopausal significant independent predictor of BMD This study suggests that dietary calcium is a major constituent affecting lumbar spin BMD in postmenopausal women whose menopausal period is over than 5 years.

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