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1

Vitamin D and Calcium Supplementation to Prevent Fractures  

MedlinePLUS

... 1 Understanding Task Force Recommendations Vitamin D and Calcium Supplementation to Prevent Fractures The U.S. Preventive Services ... are vitamin D and calcium? Vitamin D and calcium are important nutrients that work together to keep ...

2

Calcium and Cancer Prevention: Strengths and Limits of the Evidence  

Cancer.gov

A fact sheet that summarizes the results of studies on calcium and cancer prevention. It includes information about dietary recommendations for calcium, and the amount of calcium in foods and supplements.

3

The Role of Calcium in Prevention and Treatment of Osteoporosis.  

ERIC Educational Resources Information Center

Osteoporosis results from several factors. Calcium deficiency is only one, and high calcium intake will prevent only those cases in which calcium is the limiting factor. Calcium cannot reverse, but only arrest, bone loss. A high calcium intake for every member of the population is advocated. (Author/MT)

Heaney, Robert P.

1987-01-01

4

Vitamin D and Calcium for Fracture Prevention  

Technology Transfer Automated Retrieval System (TEKTRAN)

Inadequate intakes of vitamin D and calcium lead to reduced calcium absorption, higher bone-remodeling rates and increased bone loss. Vitamin D has also been linked to muscle function and risk of falling. In older men and women, higher 25-hydroxyvitamin D [25(OH)D] levels are associated with bette...

5

Retinoic acid affects calcium signaling in adult molluscan neurons.  

PubMed

Retinoic acid, the active metabolite of vitamin A, is important for nervous system development, regeneration, as well as cognitive functions of the adult central nervous system. These central nervous system functions are all highly dependent on neuronal activity. Retinoic acid has previously been shown to induce changes in the firing properties and action potential waveforms of adult molluscan neurons in a dose- and isomer-dependent manner. In this study, we aimed to determine the cellular pathways by which retinoic acid might exert such effects, by testing the involvement of pathways previously shown to be affected by retinoic acid. We demonstrated that the ability of all-trans retinoic acid (atRA) to induce electrophysiological changes in cultured molluscan neurons was not prevented by inhibitors of protein synthesis, protein kinase A or phospholipase C. However, we showed that atRA was capable of rapidly reducing intracellular calcium levels in the same dose- and isomer-dependent manner as shown previously for changes in neuronal firing. Moreover, we also demonstrated that the transmembrane ion flux through voltage-gated calcium channels was rapidly modulated by retinoic acid. In particular, the peak current density was reduced and the inactivation rate was increased in the presence of atRA, over a similar time course as the changes in cell firing and reductions in intracellular calcium. These studies provide further evidence for the ability of atRA to induce rapid effects in mature neurons. PMID:25343782

Vesprini, Nicholas D; Dawson, Taylor F; Yuan, Ye; Bruce, Doug; Spencer, Gaynor E

2015-01-01

6

Combination reaction between humic acid and calcium ions  

Microsoft Academic Search

In the previous paper (1), liming an acid humus volcanic ash soil resulted in the formation of humic acids combined with calcium, but had no significant effect on acid brown forest soils containing humic acids of a lower degree of humification. Subsequently, the authors examined the humus composition of the soils treated with calcium acetate, and conducted some experiments on

Ryosuke Shiroya; Kyoichi Kumada

1976-01-01

7

Surface modification of precipitated calcium carbonate using aqueous fluosilicic acid  

Microsoft Academic Search

Surface modification of calcium carbonate using aqueous fluosilicic acid (H2SiF6) was carried out in terms of the mole ratio of fluosilicic acid to calcium carbonate as well contact time. The resulting surface compounds of amorphous silica and calcium fluoride after surface modification were visualized on the surface of calcium carbonate. Amorphous silica was generated by the hydrolysis of silicon hexafluoride

Do Su Kim; Churl Kyoung Lee

2002-01-01

8

Serine hydrolase inhibitors block necrotic cell death by preventing calcium overload of the mitochondria and permeability transition pore formation.  

PubMed

Perturbation of calcium signaling that occurs during cell injury and disease, promotes cell death. In mouse lung fibroblasts A23187 triggered mitochondrial permeability transition pore (MPTP) formation, lactate dehydrogenase (LDH) release, and necrotic cell death that were blocked by cyclosporin A (CsA) and EGTA. LDH release temporally correlated with arachidonic acid release but did not involve cytosolic phospholipase A2? (cPLA2?) or calcium-independent PLA2. Surprisingly, release of arachidonic acid and LDH from cPLA2?-deficient fibroblasts was inhibited by the cPLA2? inhibitor pyrrophenone, and another serine hydrolase inhibitor KT195, by preventing mitochondrial calcium uptake. Inhibitors of calcium/calmodulin-dependent protein kinase II, a mitochondrial Ca(2+) uniporter (MCU) regulator, also prevented MPTP formation and arachidonic acid release induced by A23187 and H2O2. Pyrrophenone blocked MCU-mediated mitochondrial calcium uptake in permeabilized fibroblasts but not in isolated mitochondria. Unlike pyrrophenone, the diacylglycerol analog 1-oleoyl-2-acetyl-sn-glycerol and CsA blocked cell death and arachidonic acid release not by preventing mitochondrial calcium uptake but by inhibiting MPTP formation. In fibroblasts stimulated with thapsigargin, which induces MPTP formation by a direct effect on mitochondria, LDH and arachidonic acid release were blocked by CsA and 1-oleoyl-2-acetyl-sn-glycerol but not by pyrrophenone or EGTA. Therefore serine hydrolase inhibitors prevent necrotic cell death by blocking mitochondrial calcium uptake but not the enzyme releasing fatty acids that occurs by a novel pathway during MPTP formation. This work reveals the potential for development of small molecule cell-permeable serine hydrolase inhibitors that block MCU-mediated mitochondrial calcium overload, MPTP formation, and necrotic cell death. PMID:24297180

Yun, Bogeon; Lee, HeeJung; Ghosh, Moumita; Cravatt, Benjamin F; Hsu, Ku-Lung; Bonventre, Joseph V; Ewing, Heather; Gelb, Michael H; Leslie, Christina C

2014-01-17

9

Interaction of Citric or Hydrochloric Acid with Calcium Fluorapatite: Precipitation of Calcium Fluoride  

Microsoft Academic Search

The interaction of citric acid (H3Ci) with calcium fluorapatite(Ca10 F2(PO4)6) was explored for two reasons: (i) to determine the role of the acid in the dissolution process and hence in the mechanism of tooth fluoridation and (ii) to determine whether there is any formation of calcium citrate. It was found that the concentration of calcium or fluoride ions is not

Dwarika Nath Misra

1999-01-01

10

Calcium antagonists in the prevention of motion sickness.  

PubMed

Flunarizine is a calcium antagonist which has proved clinically useful in controlling chronic vertigo. In a double blind crossover trial 10 subjects were used to compare the electronystagmic responses to motion in patients taking flunarizine, prochlorperazine maleate, or placebo. Flunarizine is shown to be a powerful peripherally acting labyrinthine suppressant, with application in the prevention of motion sickness. Flunarizine produces none of the central depressive side effects characteristic of antihistamines and anticholinergics, which are the conventional anti-motion sickness drugs. PMID:3510617

Lee, J A; Watson, L A; Boothby, G

1986-01-01

11

Effects and interactions of gentamicin, polyaspartic acid and diuretics on urine calcium concentration.  

PubMed

Gentamicin causes isolated, reversible calciuria in rats by an unknown mechanism. We hypothesized that gentamicin calciuria is related to nonantibacterial properties that may interfere with transtubular calcium transport (calcium channel blockade, Na,K-ATPase inhibition or competition with calcium for binding to the brush-border membrane). The calciuric effect of gentamicin was compared to the calcium channel blockers lanthanum and cobalt, the Na,K-ATPase inhibitor ouabain and the polycation aprotinin (which competes with gentamicin for brush-border membrane binding). Although gentamicin 0.02 mmol/kg caused a 6-8-fold increase in urine calcium concentration, none of the other agents was calciuric. We also found that the calciuric effects of gentamicin and furosemide were additive, whereas the noncalciuric diuretic chlorothiazide had no effect on gentamicin calciuria. We also determined the effect of poly-L-aspartic acid (PAA), which binds gentamicin and prevents nephrotoxicity. PAA caused isolated calciuria similar in magnitude and character to gentamicin. However, PAA pretreatment decreased the magnitude of gentamicin calciuria to insignificance. PAA pretreatment did not prevent furosemide calciuresis. These results indicate that: 1) gentamicin and furosemide calciuria are caused by different mechanisms; 2) gentamicin calciuria is probably not mediated by calcium channel blockade, Na,K-ATPase inhibition or displacement of brush-border membrane-bound calcium; 3) gentamicin and PAA calciuria may reflect interference with intracellular events related to transtubular calcium transport. PMID:7714777

Elliott, W C; Patchin, D S

1995-04-01

12

Solubility of calcium soaps of gum rosin, rosin acids and fatty acids  

Microsoft Academic Search

Summary  The solubility of calcium soaps of rosin acids and fatty acids have been determined and compared.\\u000a \\u000a The solubility of calcium soaps of rosin acids (d-pimaric, dihydroabietic, and l-abietic acids) present in gum rosin was found\\u000a to be greater than that of the calcium soaps of the following saturated fatty acids: lauric, myristic, palmitic, and stearic\\u000a acids.\\u000a \\u000a \\u000a \\u000a The calcium oleate was

W. D. Pohle

1941-01-01

13

Folic acid and birth defect prevention  

MedlinePLUS

Prevention of birth defects with folic acid (folate) ... There is good evidence that taking folic acid before and during pregnancy can reduce the risk of certain birth defects ( spina bifida , anencephaly , and some heart defects). Experts recommend taking 400 ...

14

Method for evaluating acid-base properties of complex calcium greases  

Microsoft Academic Search

The active components that determine the properties of complex calcium greases are salts of fatty acids, together with unreacted acids and calcium hydroxide. The acid-base properties of the grease depend on the content of these components, in particular on the ratio of hydroxide constituents (basic salts of fatty acids, calcium hydroxide) and acidic constituents (acid soaps, fatty acids). In order

I. G. Dagaeva; V. A. Kuznetsov; V. P. Korolenko; M. B. Nakonechnaya

1974-01-01

15

Hybrid Crystals of Calcium Carbonate and Amino Acids  

Microsoft Academic Search

We have investigated the effects of amino acids on the crystallization of calcium carbonate (CaCO3), and the reactivity between amino acids and CaCO3. Noncharged-polar and acidic amino acids are highly incorporated into CaCO3 and stabilize cauliflower-like grains composed of vaterite which is thermodynamically unstable in the CaCO3 polymorphs. Amino acids in the hybrid CaCO3 form radicals different from those in

Ayako Kai; Toshikatsu Miki

2000-01-01

16

Conjugated linoleic acid and calcium co-supplementation improves bone health in ovariectomised mice  

PubMed Central

Osteoporosis is a significant health concern for the elderly; conjugated linoleic acid (CLA) has been shown to improve overall bone mass when calcium is included as a co-supplement. However, potential effects of CLA and calcium on bone mass during a period of bone loss have not been reported. The purpose of this study was to determine how dietary calcium modulates the effects of conjugated linoleic acid (CLA) in preventing bone loss, using an ovariectomised mouse model. CLA supplementation significantly prevented ovariectomy-associated weight and fat mass gain, compared to non-supplemented controls. CLA significantly increased bone markers without major changes in bone mineral composition in the femur compared to respective controls. CLA treatment increased serum parathyroid hormone (PTH) significantly (p = 0.0172), while serum 1,25-dihydroxyvitamin D3 concentration was not changed by CLA. Meanwhile, CLA significantly reduced femur tartrate resistant acid phosphatase (TRAP) activity, suggesting potential reduction of osteoclastogenesis. The data suggest that CLA, along with dietary calcium, has great potential to be used to prevent bone loss and weight gain associated with menopause. PMID:23578644

Park, Yooheon; Kim, Jonggun; Scrimgeour, Angus G.; Condlin, Michelle L.; Kim, Daeyoung; Park, Yeonhwa

2013-01-01

17

Mono- and dihydroxyeicosatetraenoic acids alter calcium homeostasis in rabbit neutrophils.  

PubMed Central

Products of the lipoxygenation of arachidonic acid that express neutrophil chemotactic activity were examined in vitro for effects on the uptake of 45Ca by rabbit peritoneal neutrophils. At optimally chemotactic concentrations, 5- and 11-hydroperoxyeicosatetraenoic acid, 11- and 12L-hydroxyeicosatetraenoic acid, and leukotriene B4 enhanced 45Ca uptake within 1 min by a mean of 212-694% of the values for control neutrophils incubated in buffer alone, as compared with 75% for 5(S)-hydroxyeicosatetraenoic acid and no effect for 15-hydroperoxyeicosatetraenoic acid and 15-hydroxyeicosatetraenoic acid. The approximate rank of potency of the factors stimulating 45Ca uptake was similar to that observed for chemotaxis. Leukotriene B4, in addition to stimulating the rate of 45Ca uptake into rabbit neutrophils, also displaced intracellular calcium. The net result of the leukotriene B4-induced changes in calcium homeostasis ws to elevate transiently the intracellular level of exchangeable calcium. That neutrophil lipoxygenase metabolites of endogenous arachidonic acid rapidly enhance the influx of 45Ca supports a possible role for such metabolites in general, and leukotriene B4 in particular, in the regulation of the intracellular levels of free calcium in the neutrophils and possibly in other hormonally sensitive cells in which this cation is a second messenger. PMID:6262382

Naccache, P H; Sha'afi, R I; Borgeat, P; Goetzl, E J

1981-01-01

18

Lithium prevents early cytosolic calcium increase and secondary injurious calcium overload in glycolytically inhibited endothelial cells  

SciTech Connect

Highlights: •We investigate free calcium as a central signalling element in endothelial cells. •Inhibition of glycolysis with 2-deoxy-D-glucose reduces cellular ATP. •This manoeuvre leads to a biphasic increase and overload of free calcium. •Pre-treatment with lithium for 24 h abolishes both phases of the calcium increase. •This provides a new strategy to protect endothelial calcium homeostasis and barrier function. -- Abstract: Cytosolic free calcium concentration ([Ca{sup 2+}]{sub i}) is a central signalling element for the maintenance of endothelial barrier function. Under physiological conditions, it is controlled within narrow limits. Metabolic inhibition during ischemia/reperfusion, however, induces [Ca{sup 2+}]{sub i} overload, which results in barrier failure. In a model of cultured porcine aortic endothelial monolayers (EC), we addressed the question of whether [Ca{sup 2+}]{sub i} overload can be prevented by lithium treatment. [Ca{sup 2+}]{sub i} and ATP were analysed using Fura-2 and HPLC, respectively. The combined inhibition of glycolytic and mitochondrial ATP synthesis by 2-desoxy-D-glucose (5 mM; 2-DG) plus sodium cyanide (5 mM; NaCN) caused a significant decrease in cellular ATP content (14 ± 1 nmol/mg protein vs. 18 ± 1 nmol/mg protein in the control, n = 6 culture dishes, P < 0.05), an increase in [Ca{sup 2+}]{sub i} (278 ± 24 nM vs. 71 ± 2 nM in the control, n = 60 cells, P < 0.05), and the formation of gaps between adjacent EC. These observations indicate that there is impaired barrier function at an early state of metabolic inhibition. Glycolytic inhibition alone by 10 mM 2-DG led to a similar decrease in ATP content (14 ± 2 nmol/mg vs. 18 ± 1 nmol/mg in the control, P < 0.05) with a delay of 5 min. The [Ca{sup 2+}]{sub i} response of EC was biphasic with a peak after 1 min (183 ± 6 nM vs. 71 ± 1 nM, n = 60 cells, P < 0.05) followed by a sustained increase in [Ca{sup 2+}]{sub i}. A 24-h pre-treatment with 10 mM of lithium chloride before the inhibition of ATP synthesis abolished both phases of the 2-DG-induced [Ca{sup 2+}]{sub i} increase. This effect was not observed when lithium chloride was added simultaneously with 2-DG. We conclude that lithium chloride abolishes the injurious [Ca{sup 2+}]{sub i} overload in EC and that this most likely occurs by preventing inositol 3-phosphate-sensitive Ca{sup 2+}-release from the endoplasmic reticulum. Though further research is needed, these findings provide a novel option for therapeutic strategies to protect the endothelium against imminent barrier failure.

Bosche, Bert, E-mail: bert.bosche@uk-essen.de [Department of Neurology, University of Duisburg-Essen (Germany) [Department of Neurology, University of Duisburg-Essen (Germany); Max Planck Institute for Neurological Research with Klaus-Joachim-Zülch Laboratories of the Max Planck Society and the Medical Faculty of the University of Cologne (Germany); Schäfer, Matthias, E-mail: matthias.schaefer@sanofi.com [Institute of Physiology, Justus-Liebig-University Giessen (Germany)] [Institute of Physiology, Justus-Liebig-University Giessen (Germany); Graf, Rudolf, E-mail: rudolf.graf@nf.mpg.de [Max Planck Institute for Neurological Research with Klaus-Joachim-Zülch Laboratories of the Max Planck Society and the Medical Faculty of the University of Cologne (Germany)] [Max Planck Institute for Neurological Research with Klaus-Joachim-Zülch Laboratories of the Max Planck Society and the Medical Faculty of the University of Cologne (Germany); Härtel, Frauke V., E-mail: frauke.haertel@tu-dresden.de [Institute of Physiology, Medical Faculty Carl Gustav Carus, Technical University Dresden (Germany); Schäfer, Ute, E-mail: ute.schaefer@medunigraz.at [Research Unit for Experimental Neurotraumatology, Medical University of Graz (Austria)] [Research Unit for Experimental Neurotraumatology, Medical University of Graz (Austria); Noll, Thomas, E-mail: thomas.noll@tu-dresden.de [Institute of Physiology, Medical Faculty Carl Gustav Carus, Technical University Dresden (Germany)] [Institute of Physiology, Medical Faculty Carl Gustav Carus, Technical University Dresden (Germany)

2013-05-03

19

Inhibiting MAP Kinase Activity Prevents Calcium Transients and Mitosis Entry in Early Sea Urchin Embryos*  

E-print Network

Inhibiting MAP Kinase Activity Prevents Calcium Transients and Mitosis Entry in Early Sea Urchin Kingdom A transient calcium increase triggers nuclear enve- lope breakdown (mitosis entry) in sea urchin embryos. Cdk1/cyclin B kinase activation is also known to be re- quired for mitosis entry. More recently

Newcastle upon Tyne, University of

20

40 CFR 721.10382 - Diphosphoric acid, calcium salt (1:1).  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false Diphosphoric acid, calcium salt (1:1). 721.10382 Section... § 721.10382 Diphosphoric acid, calcium salt (1:1). (a) Chemical substance...substance identified as diphosphoric acid, calcium salt (1:1) (PMN...

2014-07-01

21

40 CFR 721.10382 - Diphosphoric acid, calcium salt (1:1).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Diphosphoric acid, calcium salt (1:1). 721.10382 Section... § 721.10382 Diphosphoric acid, calcium salt (1:1). (a) Chemical substance...substance identified as diphosphoric acid, calcium salt (1:1) (PMN...

2013-07-01

22

40 CFR 721.10382 - Diphosphoric acid, calcium salt (1:1).  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Diphosphoric acid, calcium salt (1:1). 721.10382 Section... § 721.10382 Diphosphoric acid, calcium salt (1:1). (a) Chemical substance...substance identified as diphosphoric acid, calcium salt (1:1) (PMN...

2012-07-01

23

Calcium phosphate cements prepared by acid-base reaction  

Microsoft Academic Search

In this paper, the authors investigate the characteristics of calcium phosphate cements (CPC) prepared by an exothermic acid-base reaction between NH[sub 4]H[sub 2]PO[sub 4]-based fertilizer (Poly-N) and calcium aluminate compounds (CAC), such as 3CaO[center dot]Al[sub 2]O[sub 3] (C[sub 3]A), CaO[center dot] Al[sub 2]O[sub 3] (CA), and CaO[center dot] 2Al[sub 2]O[sub 3] (CA[sub 2]), in a series of integrated studies of

Toshifumi Sugama; Marita Allan; Janet M. Hill

1992-01-01

24

Calcium and Cancer Prevention: Strengths and Limits of the Evidence  

MedlinePLUS

... Adapted from the U.S. Department of Health and Human Services Dietary Guidelines for Americans 2005. **oz = ounces . Packaged foods are required to have a Nutrition Facts label ( 3 ). On foods that contain calcium, ...

25

Stability of calcium carbonate and magnesium carbonate in rainwater and nitric acid solutions  

Microsoft Academic Search

Carbonation of magnesium and calcium silicates has emerged as an interesting option for long term storage of captured CO2. However, carbonated minerals are not stable in acidic environments. This study was conducted to determine if synthetically carbonated minerals dissolve in acidic rain and release CO2. Synthetic magnesium and calcium carbonates were leached in nitric acid solutions of various acidities, as

Sebastian Teir; Sanni Eloneva; Carl-Johan Fogelholm; Ron Zevenhoven

2006-01-01

26

Calcium ion binding to a soil fulvic acid using a donnan potential model  

USGS Publications Warehouse

Calcium ion binding to a soil fulvic acid (Armadale Bh Horizon) was evaluated over a range of calcium ion concentrations, from pH 3.8 to 7.3, using potentiometric titrations and calcium ion electrode measurements. Fulvic acid concentration was constant (100 milligrams per liter) and calcium ion concentration varied up to 8 X 10-4 moles per liter. Experiments discussed here included: (1) titrations of fulvic acid-calcium ion containing solutions with sodium hydroxide; and (2) titrations of fully neutralized fulvic acid with calcium chloride solutions. Apparent binding constants (expressed as the logarithm of the value, log ??app) vary with solution pH, calcium ion concentration, degree of acid dissociation, and ionic strength (from log ??app = 2.5 to 3.9) and are similar to those reported by others. Fulvic acid charge, and the associated Donnan Potential, influences calcium ion-fulvic acid ion pair formation. A Donnan Potential corrrection term allowed calculation of intrinsic calcium ion-fulvic acid binding constants. Intrinsic binding constants vary from 1.2 to 2.5 (the average value is about log??= 1.6) and are similar to, but somewhat higher than, stability constants for calcium ion-carboxylic acid monodentate complexes. ?? by Oldenbourg Wissenschaftsverlag, Mu??nchen.

Marinsky, J.A.; Mathuthu, A.; Ephraim, J.H.; Reddy, M.M.

1999-01-01

27

Soil-calcium depletion linked to acid rain and forest growth in the eastern United States  

USGS Publications Warehouse

Since the discovery of acid rain in the 1970's, scientists have been concerned that deposition of acids could cause depletion of calcium in forest soils. Research in the 1980's showed that the amount of calcium in forest soils is controlled by several factors that are difficult to measure. Further research in the 1990's, including several studies by the U.S. Geological Survey, has shown that (1) calcium in forest soils has decreased at locations in the northeastern and southeastern U.S., and (2) acid rain and forest growth (uptake of calcium from the soil by roots) are both factors contributing to calcium depletion.

Lawrence, Gregory B.; Huntington, T.G.

1999-01-01

28

Interactions between red light, abscisic acid, and calcium in gravitropism  

NASA Technical Reports Server (NTRS)

The effect of red light on orthogravitropism of Merit corn (Zea mays L.) roots has been attributed to its effects on the transduction phase of gravitropism (AC Leopold, SH Wettlaufer [1988] Plant Physiol 87:803-805). In an effort to characterize the orthogravitropic transduction system, comparative experiments have been carried out on the effects of red light, calcium, and abscisic acid (ABA). The red light effect can be completely satisfied with added ABA (100 micromolar) or with osmotic shock, which is presumed to increase endogenous ABA. The decay of the red light effect is closely paralleled by the decay of the ABA effect. ABA and exogenous calcium show strong additive effects when applied to either Merit or a line of corn which does not require red light for orthogravitropism. Measurements of the ABA content show marked increases in endogenous ABA in the growing region of the roots after red light. The interpretation is offered that red light or ABA may serve to increase the cytoplasmic concentrations of calcium, and that this may be an integral part of orthogravitropic transduction.

Leopold, A. C.; LaFavre, A. K.

1989-01-01

29

Calcium  

MedlinePLUS

... following: Milk, yogurt, and cheese are the main food sources of calcium for the majority of people in ... on Calcium Minerals, MedlinePlus® For more information on food sources of calcium: U.S. Department of Agriculture's (USDA) National ...

30

Direct Identification of the Calcium-Binding Amino Acid, gamma -carboxyglutamate, in Mineralized Tissue  

Microsoft Academic Search

A direct approach has been developed for quantitative identification of the calcium-binding amino acid, gamma -carboxyglutamate, in proteins. This should be advantageous for the study of numerous systems where specific roles for the binding of calcium or other divalent cations are suspected. Investigation of mineralized tissue, where calcium-binding proteins are implicated in the mineralization process, revealed that gamma -carboxyglutamate was

Peter V. Hauschka; Jane B. Lian; Paul M. Gallop

1975-01-01

31

Global Prevention of All Folic Acid-Preventable Spina bifida and Anencephaly by 2010  

Microsoft Academic Search

Folic acid-preventable spina bifida and anencephaly are pandemic, affecting 225,000 children a year. These birth defects are as preventable as polio. As we near the eradication of polio, it is time to make the commitment to global prevention of all folic acid-preventable spina bifida and anencephaly (FA-P SBA) by 2010. Folic acid fortification of centrally processed foods, such as wheat

2002-01-01

32

Surface modification of calcium-copper hydroxyapatites using polyaspartic acid  

NASA Astrophysics Data System (ADS)

Mixed calcium-copper hydroxyapatite (Ca-CuHAp), with general formula Ca(10-x)Cux(PO4)6(OH)2, where 0 ? x ? 0.75 was prepared in aqueous medium in the presence of different concentrations of poly-L-aspartic acid (PASP). XRD, IR, TG-DTA, TEM-EDX, AFM and chemical analyses were used to characterize the structure, morphology and composition of the products. All techniques show the formation of new hybrid compounds Ca-CuHAp-PASP. The presence of the grafting moiety on the apatitic material is more significant with increasing of copper amount and/or organic concentration in the starting solution. These increases lead to the affectation of apatite crystallinity. The IR spectroscopy shows the conservation of (Psbnd OH) band of (HPO4)2- groups, suggesting that PASP acid was interacted only with metallic cations of hydroxyapatite.

Othmani, Masseoud; Aissa, Abdallah; Bachoua, Hassen; Debbabi, Mongi

2013-01-01

33

Injectable hydrogels derived from phosphorylated alginic acid calcium complexes.  

PubMed

Phosphorylation of sodium alginate salt (NaAlg) was carried out using H3PO4/P2O5/Et3PO4 followed by acid-base reaction with Ca(OAc)2 to give phosphorylated alginic acid calcium complexes (CaPAlg), as a water dispersible alginic acid derivative. The modified alginate derivatives including phosphorylated alginic acid (PAlg) and CaPAlg were characterized by nuclear magnetic resonance spectroscopy for (1)H, and (31)P nuclei, high resolution inductively coupled plasma optical emission spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. CaPAlg hydrogels were prepared simply by mixing CaPAlg solution (2w/v%) with NaAlg solution (2w/v%) in various ratios (2:8, 4:6, 6:4, 8:2) of volume. No additional calcium salts such as CaSO4 or CaCl2 were added externally. The gelation was completed within about 3-40min indicating a high potential of hydrogel delivery by injection in vivo. Their mechanical properties were tested to be ?6.7kPa for compressive strength at break and about 8.4kPa/mm for elastic modulus. SEM analysis of the CaPAlg hydrogels showed highly porous morphology with interconnected pores of width in the range of 100-800?m. Cell culture results showed that the injectable hydrogels exhibited comparable properties to the pure alginate hydrogel in terms of cytotoxicity and 3D encapsulation of cells for a short time period. The developed injectable hydrogels showed suitable physicochemical and mechanical properties for injection in vivo, and could therefore be beneficial for the field of soft tissue engineering. PMID:25842118

Kim, Han-Sem; Song, Minsoo; Lee, Eun-Jung; Shin, Ueon Sang

2015-06-01

34

CAUSAL ANALYSIS OF EXERCISE AND CALCIUM INTAKE BEHAVIORS FOR OSTEOPOROSIS PREVENTION AMONG YOUNG WOMEN IN THAILAND  

Microsoft Academic Search

The goal of health education is to provide information to affect attitudes, beliefs, and intentions for behavior change. However, little is known about the effects of changes in knowledge on behaviors for osteoporosis prevention. Our objective is to develop and test theoretical models of the effects of knowledge, attitude, and self-efficacy on exercise and calcium intake among young women before

Noppawan Piaseu; Karen Schepp; Basia Belza

2002-01-01

35

Neurobiology of Aging 27 (2006) 306317 Prevention of age-related dysregulation of calcium  

E-print Network

Neurobiology of Aging 27 (2006) 306­317 Prevention of age-related dysregulation of calcium dynamics the impact of aging and 17 -estradiol on neuronal Ca2+ homeostasis, intracellular Fura-2 Ca2+ -imaging was conducted during 20-pulses of glutamate in hippocampal neurons cultured from embryonic (E18), middle-age (10

Brinton, Roberta Diaz

36

DOCOSAHEXAENOIC ACID AND ARACHIDONIC ACID PREVENT ESSENTIAL FATTY ACID DEFICIENCY AND HEPATIC STEATOSIS  

PubMed Central

Objectives Essential fatty acids are important for growth, development, and physiologic function. Alpha-linolenic acid and linoleic acid are the precursors of docosahexaenoic and arachidonic acid, respectively, and have traditionally been considered the essential fatty acids. However, we hypothesized that docosahexaenoic acid and arachidonic acid can function as the essential fatty acids. Methods Using a murine model of essential fatty acid deficiency and consequent hepatic steatosis, we provided mice with varying amounts of docosahexaenoic and arachidonic acids to determine whether exclusive supplementation of docosahexaenoic and arachidonic acids could prevent essential fatty acid deficiency and inhibit or attenuate hepatic steatosis. Results Mice supplemented with docosahexaenoic and arachidonic acids at 2.1% or 4.2% of their calories for 19 days had normal liver histology and no biochemical evidence of essential fatty acid deficiency, which persisted when observed after 9 weeks. Conclusion Supplementation of sufficient amounts of docosahexaenoic and arachidonic acids alone without alpha-linolenic and linoleic acids meets essential fatty acid requirements and prevents hepatic steatosis in a murine model. PMID:22038210

Le, Hau D.; Meisel, Jonathan A.; de Meijer, Vincent E.; Fallon, Erica M.; Gura, Kathleen M.; Nose, Vania; Bistrian, Bruce R.; Puder, Mark

2012-01-01

37

The role of calcium in improving photosynthesis and related physiological and biochemical attributes of spring wheat subjected to simulated acid rain.  

PubMed

The response of photosynthesis parameters, catalase, superoxide dismutase and peroxidase activity, malondialdehyde, proline, chlorophyll, yield and yield components to foliar application of calcium and simulated acid rain in wheat were investigated. Foliar treatment of calcium led to significant increases in the photosynthesis rate, transpiration rate, stomatal conductance, proline, chlorophyll, yield and yield components in plants subjected to acid rain. Antioxidant enzyme activity and lipid peroxidation in the wheat leaves decreased because of calcium foliar application. Calcium hindered degradation of the rubisco subunits under acid rain treatment compared with water-treated plants. Results suggest that acid rain induces the production of free radicals resulting in lipid peroxidation of the cell membrane so that significant increase in antioxidant enzyme activity was observed. In addition, photosynthetic parameters i.e. photosynthesis rate, transpiration rate and stomatal conductance were drastically suppressed by acid rain. The cellular damage caused by free radicals might be reduced or prevented by a protective metabolism including antioxidative enzymes and calcium. We report that foliar application of calcium before acid rain may ameliorate the adverse effects of acid rain in wheat plants. PMID:24431486

Dolatabadian, Aria; Sanavy, Seyed Ali Mohammad Modarres; Gholamhoseini, Majid; Joghan, Aydin Khodaei; Majdi, Mohammad; Kashkooli, Arman Beyraghdar

2013-04-01

38

Comparative effects of oral aromatic and branched-chain amino acids on urine calcium and excretion  

Technology Transfer Automated Retrieval System (TEKTRAN)

Aromatic amino acids (AAAs) bind to the calcium sensor receptor (CaR) but branched-chain amino acids (B-CAAs) do not; by binding to this receptor, AAAs have an increased potential to affect calcium homeostasis. This study was conducted to determine and compare the effects of AAAs and B-CAAs on calci...

39

Calcium  

MedlinePLUS

... loss. Some clinical research shows that increasing calcium consumption from dairy products such as yogurt seems to ... and vitamin D. For weight loss, increasing calcium consumption from dairy products to total intake of 500- ...

40

Calcium  

MedlinePLUS

... strong bones and teeth. Why Do I Need Calcium? Bones grow rapidly during adolescence, and teens need ... salmon with bones. Almond milk. Back Continue Working Calcium Into Your Diet Looking for ways to up ...

41

Calcium  

MedlinePLUS

... and blood vessels contract and expand, to secrete hormones and enzymes and to send messages through the nervous system. It is important to get plenty of calcium in the foods you eat. Foods rich in calcium include Dairy ...

42

21 CFR 872.3490 - Carboxymethylcellulose sodium and/or polyvinylmethylether maleic acid calcium-sodium double salt...  

Code of Federal Regulations, 2010 CFR

...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. 872.3490 Section...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. (a) Identification...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive is a device...

2010-04-01

43

21 CFR 872.3490 - Carboxymethylcellulose sodium and/or polyvinylmethylether maleic acid calcium-sodium double salt...  

Code of Federal Regulations, 2014 CFR

...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. 872.3490 Section...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. (a) Identification...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive is a device...

2014-04-01

44

21 CFR 872.3490 - Carboxymethylcellulose sodium and/or polyvinylmethylether maleic acid calcium-sodium double salt...  

Code of Federal Regulations, 2013 CFR

...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. 872.3490 Section...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. (a) Identification...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive is a device...

2013-04-01

45

21 CFR 872.3490 - Carboxymethylcellulose sodium and/or polyvinylmethylether maleic acid calcium-sodium double salt...  

Code of Federal Regulations, 2011 CFR

...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. 872.3490 Section...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. (a) Identification...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive is a device...

2011-04-01

46

21 CFR 872.3490 - Carboxymethylcellulose sodium and/or polyvinylmethylether maleic acid calcium-sodium double salt...  

Code of Federal Regulations, 2012 CFR

...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. 872.3490 Section...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. (a) Identification...polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive is a device...

2012-04-01

47

Healing and Preventive Effects of Calcium Alginate on Carbon Tetrachloride Induced Liver Injury in Rats  

PubMed Central

The purpose of this study was to investigate the pharmacological effects of calcium alginate on carbon tetrachloride (CCL4)-induced hepatotoxicity in rats. The study included two experiments. In the first experiment the animals were given daily CCL4 through gavage for 7 days and then 10, 50, or 250 mg/kg b.w. of calcium alginate for 21 days. The increased bilirubin level, enhanced alanine and aspartate aminotransferase activity in plasma and reduced liver glycogen content induced by CCL4 were partly normalized by alginate administration in a dose-dependent manner. In addition, alginate significantly improved CCL4-induced alterations of pro-oxidant and antioxidant biochemical parameters in liver and plasma compared to those of rats administered CCL4. In the second experiment the animals were given daily 10, 50 or 250 mg/kg b.w. of calcium alginate for 21 days before 7-day administration of CCL4. Pretreatment with alginate before CCL4 administration resulted in significantly inhibited increase of the blood enzymatic activities of alanine and aspartate aminotransferases and bilirubin level in a dose-dependent manner. Also, preliminary administration of alginate prevented elevation of lipid peroxidation products and reduction of liver glutathione content in rats given CCL4. These results suggest that calcium alginate exerts healing and preventive effects on CCL4-induced hepatotoxicity in rats.

Khotimchenko, Yuri S.; Khotimchenko, Maxim Y.

2004-01-01

48

J Bone Miner Res . Author manuscript Proteins, dietary acid load, and calcium and risk of postmenopausal  

E-print Network

the association between protein intake and the overall acid-base equilibrium of the diet (as renal net acid to neutralize acid generated from high-prJ Bone Miner Res . Author manuscript Page /1 10 Proteins, dietary acid load, and calcium and risk

Paris-Sud XI, Université de

49

Interactions of calcium and fulvic acid at the goethite-water interface  

Microsoft Academic Search

Interactions of calcium and fulvic acid (Strichen) with the surface of goethite were studied with batch and titration experiments. The mutual influence of the interactions on the adsorption of fulvic acid, calcium ions and protons were examined. Adsorption of the fulvic acid to goethite decreased with increase in pH (pH range 3 11). Addition of Ca (1.0 mM) at intermediate

Li Ping Weng; Luuk K. Koopal; Tjisse Hiemstra; Johannes C. L. Meeussen; Willem H. van Riemsdijk

2005-01-01

50

Interactions of calcium and fulvic acid at the goethite-water interface  

Microsoft Academic Search

Interactions of calcium and fulvic acid (Strichen) with the surface of goethite were studied with batch and titration experiments. The mutual influence of the interactions on the adsorption of fulvic acid, calcium ions and protons were examined. Adsorption of the fulvic acid to goethite decreased with increase in pH (pH range 3–11). Addition of Ca (1.0 mM) at intermediate and

Li Ping Weng; Luuk K. Koopal; Tjisse Hiemstra; Johannes C. L. Meeussen; Willem H. Van Riemsdijk

2005-01-01

51

Folic Acid for the Prevention of Infant Neural Tube Defects: U.S. Preventive Services Task Force Recommendation  

MedlinePLUS

Folic Acid for the Prevention of Infant Neural Tube Defects: U.S. Preventive Services Task Force Recommendation Summaries for Patients ... modern medicine. The full reports are titled “Folic Acid for the Prevention of Neural Tube Defects: U.S. ...

52

Location and nature of calcium-binding sites in salivary acidic proline-rich phosphoproteins  

Microsoft Academic Search

The location of the calcium-binding sites in the human acidic proline-rich proteins, salivary proteins A and C, was determined by equilibrium dialysis of the tryptic peptides with buffers containing ⁴⁵Ca. All the calcium-binding sites are located in the NHâ-terminal tryptic peptide (TX peptide). The nature of the calcium binding sites in the TX peptide and native salivary proteins A and

A. Bennick; A. C. McLaughlin; A. A. Grey; G. Madapallimattam

1981-01-01

53

Calcium supplements  

MedlinePLUS

... enough calcium over your lifetime can help prevent osteoporosis . Most people get enough calcium in their normal diet. Calcium is found in dairy foods and leafy green vegetables. Older women and men ...

54

Acid diet (high meat protein) effects on calcium metabolism and bone health  

Technology Transfer Automated Retrieval System (TEKTRAN)

Purpose of review: Update recent advancements regarding the effect of high animal protein on calcium utilization and bone health. Recent findings: Increased potential renal acid load resulting from a high protein (meat) intake has been closely associated with increased urinary calcium excretion. How...

55

Nonstarter Lactic Acid Bacteria and Aging Temperature Affect Calcium Lactate Crystallization in Cheddar Cheese  

Microsoft Academic Search

The occurrence of unappetizing calcium lactate crys- tals in Cheddar cheese is a challenge and expense to manufacturers, and this research was designed to un- derstand their origin. It was hypothesized that non- starter lactic acid bacteria (NSLAB) affect calcium lac- tate crystallization (CLC) by producing D(?)-lactate. This study was designed to understand the effect of NSLAB growth and aging

Y.-E. Chou; C. G. Edwards; L. O. Luedecke; M. P. Bates; S. Clark

2003-01-01

56

Poly (vinylsulfonic acid) assisted synthesis of aqueous solution stable vaterite calcium carbonate nanoparticles.  

PubMed

Calcium carbonate nanoparticles of the vaterite polymorph were synthesized by combining CaCl2 and Na2CO3 in the presence of poly (vinylsulfonic acid) (PVSA). By studying the important experimental parameters we found that controlling PVSA concentration, reaction temperature, and order of reagent addition the particle size, monodispersity, and surface charge can be controlled. By increasing PVSA concentration or by decreasing temperature CCNPs with an average size from ?150 to 500 nm could be produced. We believe the incorporation of PVSA into the reaction plays a dual role to (1) slow down the nucleation rate by sequestering calcium and to (2) stabilize the resulting CCNPs as the vaterite polymorph, preventing surface calcification or aggregation into microparticles. The obtained vaterite nanoparticles were found to maintain their crystal structure and surface charge after storage in aqueous buffer for at least 5 months. The aqueous stable vaterite nanoparticles could be a useful platform for the encapsulation of a large variety of biomolecules for drug delivery or as a sacrificial template toward capsule formation for biosensor applications. PMID:24461857

Nagaraja, Ashvin T; Pradhan, Sulolit; McShane, Michael J

2014-03-15

57

A new CO 2 disposal process via artificial weathering of calcium silicate accelerated by acetic acid  

Microsoft Academic Search

A new disposal process for anthropogenic CO2 via an artificially accelerated weathering reaction is proposed to counteract global warming. The process is essentially composed of the following two steps:(1)CaSiO3+2CH3COOH?Ca2++2CH3COO?+H2O+SiO2(2)Ca2++2CH3COO?+CO2+H2O?CaCO3?+2CH3COOHStep (1) is the extraction of calcium ions by acetic acid from calcium silicate, for example, wollastonite rocks. Step (2) is the deposition of calcium carbonate from the solution of calcium ions

M. Kakizawa; A. Yamasaki; Y. Yanagisawa

2001-01-01

58

SEMI-BATCH PRECIPITATION OF CALCIUM SULFATE DIHYDRATE FROM CALCITE AND SULFURIC ACID  

E-print Network

SEMI-BATCH PRECIPITATION OF CALCIUM SULFATE DIHYDRATE FROM CALCITE AND SULFURIC ACID Frédéric BARD1 a calcite suspension to a sulfuric acid solution from industrial waste. The morphology of the precipitated, sulfuric acid, industrial waste. 1. INTRODUCTION Gypsum is a mineral compound of first importance

Paris-Sud XI, Université de

59

Developing precipitation modes for preventing the calcium-oxalate contamination of sugar beet pectins.  

PubMed

Effects of precipitation modes on the co-precipitation of insoluble oxalates particles during the purification of sugar beet pectins (SBP) from the extract were investigated. It was observed that soluble oxalate ions formed insoluble oxalate salts with calcium and precipitated with pectins during ethanol precipitation as pH of the medium increased and the solvent changed from water to ethanol-water mixture. Comparison among the employed precipitation methods revealed that both the dialysis-ethanol-precipitation and metal precipitation effectively prevented the calcium-oxalate contamination of SBP. Emulsifying properties of DEPP, EPP and MPP were also studied. It was observed that DEPP performed better than the remainder with respect to emulsifying ability. Based on these results, we concluded that the dialysis-ethanolic-precipitation can be a suitable method for improving the purity as well as emulsifying properties of the resulting pectins. PMID:25842309

Guo, Xiaoming; Meng, Hecheng; Zhu, Siming; Tang, Qiang; Pan, Runquan; Yu, Shujuan

2015-09-01

60

Calcium channel blocker prevents stress-induced activation of renin and aldosterone in conscious pig.  

PubMed

A considerable amount of data suggest the involvement of calcium-mediated processes in the activation of the renin-angiotensin-aldosterone (RAA) cascade. To investigate the effect of calcium-channel inhibition on the RAA system, we studied 21 conscious pigs. Blood renin and aldosterone levels increased by subjecting animals to 24 hours of immobilization stress. Renin and aldosterone levels were repeatedly measured by radio-immunoassay in blood samples taken periodically over 24 hours from a chronically implanted arterial cannula. Pretreatment of the animals (N = 11) with nisoldipine, 2 x 20 mg p.o. daily for 2 days before and on the day of immobilization, transiently attenuated the stress-induced increase of plasma renin activity and completely prevented the rise of aldosterone, as compared to nontreated controls (N = 10). The finding that nisoldipine suppresses RAA activation induced by a nonpharmacologic stimulus in the conscious intact animal may have clinical implications. PMID:1878334

Ceremuzy?ski, L; Klo?, J; Barcikowski, B; Herbaczy?ska-Cedro, K

1991-06-01

61

Relationship between calcium and uroinic acids in the encystment of Azotobacter vinelandii.  

PubMed Central

Encystment of Azotobacter vinelandii (ATCC 12837) in modified Burk nitrogen-free medium (pH 7.0) containing 0.2 percent beta-hydroxybutyrate occurs optimally in 0.37 to 0.44 mM solutions of calcium ions. Suspension of cells in media deficient in calcium results in abortive encystment characterized by the release of viscous cyst coat material. Mature cysts rupture in ethylene glycol-bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid, suggesting that calcium is a structural component of the cyst coat. Maximal stimulation of encystment by calcium ions occurs prior to the completion of the cyst exine or outer coat. The uronic acid composition of cyst components is dependent on calcium levels in the medium. Uronic acids account for 31.7 percent of the intine (inner coat) and 13 percent of the exine dry weight, and only mannuronic and guluronic acids are present in these fractions. These can be extracted as homo- and heteropolymeric sequence "blocks" characteristic of alginic acids. The polyuronic acid fraction of both the cyst coats contain approximately equal amounts of heteropolymeric (mannuronic acid/guluronic acid) blocks. The exine, however, is richer in polyguluronic acid and the intine is richer in polymannuronic acid. As a result, the mannuronic acid/guluronic acid ratio of the exine is lower than that of the intine. Slimes that form in abortive encystment are rich in polymannuronic acid and have a high mannuronic acid/guluronic acid ratio. A polymannuronic acid 5-epimerase is active in the mature cyst central body and the encystment culture fluid. PMID:235508

Page, W J; Sadoff, H L

1975-01-01

62

Effect of Fatty Acids or Calcium Soaps on Rumen and Total Nutrient Digestibility of Dairy Rations1  

Microsoft Academic Search

Two trials ascertained whether feeding fatty acids as preformed calcium soaps would permit normal digestibility of fiber without reducing availabilities of fatty acids or energy. Six diets contained no added fat (control) or the equivalent of 4.5% added fatty acids as tallow or soy fatty acids, tallow or soy calcium soaps, or tallow combined with the nonnutritive carrier verxite. Six

T. C. Jenkins; D. L. Palmquist

1984-01-01

63

Aspirin plus calcium supplementation to prevent superimposed preeclampsia: a randomized trial  

PubMed Central

Preeclampsia is an important cause of maternal and perinatal morbidity and mortality. Previous studies have tested calcium supplementation and aspirin separately to reduce the incidence of preeclampsia but not the effects of combined supplementation. The objective of this study was to investigate the effectiveness of aspirin combined with calcium supplementation to prevent preeclampsia in women with chronic hypertension. A double-blind, placebo-controlled randomized clinical trial was carried out at the antenatal clinic of a large university hospital in São Paulo, SP, Brazil. A total of 49 women with chronic hypertension and abnormal uterine artery Doppler at 20-27 weeks gestation were randomly assigned to receive placebo (N = 26) or 100 mg aspirin plus 2 g calcium (N = 23) daily until delivery. The main outcome of this pilot study was development of superimposed preeclampsia. Secondary outcomes were fetal growth restriction and preterm birth. The rate of superimposed preeclampsia was 28.6% lower among women receiving aspirin plus calcium than in the placebo group (52.2 vs 73.1%, respectively, P=0.112). The rate of fetal growth restriction was reduced by 80.8% in the supplemented group (25 vs 4.8% in the placebo vs supplemented groups, respectively; P=0.073). The rate of preterm birth was 33.3% in both groups. The combined supplementation of aspirin and calcium starting at 20-27 weeks of gestation produced a nonsignificant decrease in the incidence of superimposed preeclampsia and fetal growth restriction in hypertensive women with abnormal uterine artery Doppler. PMID:24728212

Souza, E.V.; Torloni, M.R.; Atallah, A.N.; dos Santos, G.M.S.; Kulay, L.; Sass, N.

2014-01-01

64

Development of poly(aspartic acid-co-malic acid) composites for calcium carbonate and sulphate scale inhibition.  

PubMed

Polyaspartic acid (PSI) is suitable for the inhibition of inorganic scale deposition. To enhance its scale inhibition efficiency, PSI was modified by reacting aspartic acid with malic acid (MA) using thermal polycondensation polymerization. This reaction resulted in poly(aspartic acid-co-malic acid) (PSI-co-MA) dual polymer. The structural, chemical and thermal properties of the dual polymers were analysed by using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry and gel permeation chromatography. The effectiveness of six different molar ratios of PSI-co-MA dual polymer for calcium carbonate and calcium sulphate scale inhibition at laboratory scale batch experiments was evaluated with synthetic brine solution at selected doses of polymer at 65-70°C by the static scale test method. The performance of PSI-co-MA dual polymer for the inhibition of calcium carbonate and calcium sulphate precipitation was compared with that of a PSI single polymer. The PSI-co-MA exhibited excellent ability to control inorganic minerals, with approximately 85.36% calcium carbonate inhibition and 100% calcium sulphate inhibition at a level of 10?mg/L PSI-co-MA, respectively. Therefore, it may be reasonably concluded that PSI-co-MA is a highly effective scale inhibitor for cooling water treatment applications. PMID:25371160

Mithil Kumar, N; Gupta, Sanjay Kumar; Jagadeesh, Dani; Kanny, K; Bux, F

2015-05-01

65

Dietary supplementation of calcium may counteract obesity in mice mediated by changes in plasma fatty acids.  

PubMed

The scope of this study was to assess the impact of calcium and conjugated linoleic acid (CLA) supplementation on plasma fatty acid profiles and to evaluate potential synergistic effects of both compounds against dietary obesity. Mice separated into five experimental groups were followed: control (C), high-fat diet (HF), HF with calcium (Ca), HF plus CLA and HF with both Ca and CLA. Plasma metabolites and fatty acids were determined by commercial kits and gas chromatography, respectively. Both dietary calcium and CLA supplementation contributed to lower body fat gain under a HF diet. Maximum efficacy was seen with calcium; no additional effect was associated with the combined treatment with CLA. Plasma leptin, adiponectin and HOMA index were in accordance with an altered glucose/insulin homeostasis in the HF and HF + CLA groups, whereas control levels were attained under Ca-enriched diets. Plasma fatty acids showed minor changes associated to CLA treatment, but a high impact on PUFA was observed under Ca-enriched diets. Our results show that the mechanism underlying the anti-obesity effects of calcium supplementation is mediated mainly by changes in PUFA plasma profile. In addition, the lack of synergy on body weight reduction in combination with associated lipid profiles of calcium and CLA suggests that calcium may interfere with absorption and/or bioactivity of CLA, which can be of relevance when using CLA-fortified dairy products against human obesity. PMID:23729396

Laraichi, Sarah; Parra, Pilar; Zamanillo, Rocío; El Amarti, Ahmed; Palou, Andreu; Serra, Francisca

2013-08-01

66

Glycine enhances microglial intracellular calcium signaling. A role for sodium-coupled neutral amino acid transporters.  

PubMed

The inhibitory neurotransmitter glycine is known to enhance microglial nitric oxide production. However, up to now, the mechanism is undocumented. Since calcium is an important second messenger in both immune and glial cells, we studied the effects of glycine on intracellular calcium signaling. We found that millimolar concentrations of glycine enhance microglial intracellular calcium transients induced by 100 ?M ATP or by 500 nM thapsigargin. This modulation was unaffected by the glycine receptor antagonist strychnine and could not be mimicked by glycine receptor agonists such as taurine or ?-alanine, indicating glycine receptor independency. The modulation of calcium responses could be mimicked by several structurally related amino acids (e.g., serine, alanine, or glutamine) and was inhibited in the presence of the neutral amino acid transporter substrate ?-aminoisobutyric acid (AIB). We correlated these findings to immunofluorescence glycine uptake experiments which showed a clear glycine uptake which was inhibited by AIB. Furthermore, all amino acids that were shown to modulate calcium responses also evoked AIB-sensitive inward currents, mainly carried by sodium, as demonstrated by patch clamp experiments. Based on these findings, we propose that sodium-coupled neutral amino acid transporters are responsible for the observed glycine modulation of intracellular calcium responses. PMID:21350800

Van den Eynden, Jimmy; Notelaers, Kristof; Brône, Bert; Janssen, Daniel; Nelissen, Katherine; Sahebali, Sheen; Smolders, Inge; Hellings, Niels; Steels, Paul; Rigo, Jean-Michel

2011-04-01

67

Phosphate coating on pyrite to prevent acid mine drainage  

Microsoft Academic Search

Acid mine drainage (AMD) is a serious environmental problem that preoccupies the Canadian Mineral Industry. Considerable amounts of money are spent every year in an effort to prevent or reduce the acid mine drainage phenomenon. AMD occurs when sulfide minerals (ex. pyrite) contained in rock are exposed to air and water and subsequently oxidize to produce low pH water. This

Kostas Fytas; Bill Evangelou

1998-01-01

68

BENCH-SCALE EVALUATION OF CALCIUM SORBENTS FOR ACID GAS EMISSION CONTROL  

EPA Science Inventory

Calcium sorbents for acid gas emission control were evaluated for effectiveness in removing SO2/HCl and SO2/NO from simulated incinerator and boiler flue gases. All tests were conducted in a bench-scale reactor (fixed-bed) simulating fabric filter conditions in an acid gas remova...

69

Catechin prevents the calcium oxalate monohydrate induced renal calcium crystallization in NRK-52E cells and the ethylene glycol induced renal stone formation in rat  

PubMed Central

Background Reactive oxygen species play important roles in renal calcium crystallization. In this study, we examined the effects of catechin, which have been shown to have antioxidant properties on the renal calcium crystallization. Methods In the vitro experiment, the changes of the mitochondrial membrane potential, expression of superoxide dismutase (SOD), 4-hydroxynonenal (4-HNE), cytochrome c, and cleaved caspase 3 were measured to show the effects of catechin treatment on the NRK-52E cells induced by calcium oxalate monohydrate (COM). In the vivo study, Sprague–Dawley rats were administered 1% ethylene glycol (EG) to generate a rat kidney stone model and then treated with catechin (2.5 and 10 mg/kg/day) for 14 days. The urine and serum variables were dected on 7 and 14 days after EG administration. The expression of cytochrome c, cleaved caspase 3, SOD, osteopontin (OPN), malondialdehyde (MDA), 8-hydroxy-2?-deoxyguanosine (8-OHdG) in kidney were measured. Furthermore, the mitochondrial microstructure in the kidney was also examined by transmission electron microscopy. Results Catechin treatment could prevent the changes in mitochondrial membrane potential and expression of SOD, 4-HNE, cytochrome c, and cleaved caspase 3 in NRK-52E cells induced by the COM. For the in vivo experiments, the EG administration induced renal calcium crystallization was also prevented by the catechin. The expression of SOD, OPN, MDA, OPN and 8-OHdG, were increased after EG administration and this increase was diminished by catechin. Moreover, catechin also prevented EG induced mitochondrial collapse in rat. Conclusions Catechin has preventive effects on renal calcium crystallization both in vivo and in vitro, and provide a potential therapeutic treatment for this disease. PMID:24044655

2013-01-01

70

[Chemical structure of dicarboxylic acids and their capacity inhibiting of calcium oxalate crystal growth].  

PubMed

The effect of dicarboxylic acids with a three C-C bonds distance on the crystallization of calcium oxalate (CaOxa) was investigated in silica gel system by means of X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). These acids include succinic acid, maleic acid, fumaric acid, malic acid, L-aspartic acid and tartaric acid. All the dicarboxylic acids can inhibit the aggregation of calcium oxalate monohydrate (COM) and induce the formation of calcium oxalate dehydrate (COD). But their ability to inhibit the growth and aggregation of COM, to diminish the specific surface area of COM and to induce COD formation were strengthened as the number of the substituted hydroxyl or amino group increased. The molecular mechanisms were discussed in terms of chemical structures of dicarboxylic acids. Only the dicarboxylic acids with a HOOC-CH(R)-CH2-COOH (R=OH or NH2) group were found to have the best inhibitory effect on the CaOxa urinary stones. The results could provide some clue to looking for new drugs for urinary stones in clinic. PMID:18306777

Deng, Sui-ping; Hu, Peng; Ouyang, Jian-ming

2007-10-01

71

Glutaraldehyde, gamma-carboxyglutamic acid and calcium in explanted bioprosthetic heart valves.  

PubMed

This paper describes the determination of glutaraldehyde, gamma-carboxylglutamic acid (gamma-CGA) and calcium concentrations in nine bioprosthetic heart valves after explantation. The glutaraldehyde and gamma-CGA were determined by high performance liquid chromatography (HPLC) procedures and the calcium by atomic absorption spectrometry. Glutaraldehyde was detectable in only two of these valves at levels of 17% and 2% of that present in an unimplanted valve. The results indicate that there is no correlation between gamma-CGA and calcium deposition, indicating that the gamma-CGA is probably absorbed onto the forming calcium deposit from the circulation and does not contribute to the calcification process, and that the acid hydrolysable glutaraldehyde decreases with time during implantation. There is, however, no correlation between the duration of implantation and the decrease in glutaraldehyde concentration. PMID:8162207

Hughes, H; Tipton, L S; Feuchuk, D; Prabhakar, G; Aboul-Enein, H Y; Duran, C M

1994-01-01

72

Degradation of poly(ethylene- co-methacrylic acid)–calcium carbonate nanocomposites  

Microsoft Academic Search

Composites of poly(ethylene-co-methacrylic acid) with 5 mass fraction percent of precipitated calcium carbonate nanoparticles were prepared by melt extrusion on a miniature melt-blender and medium-scale production equipment. The composites consisted mostly of isolated particles. The ultimate mechanical properties of the nanocomposites were consequently largely superior to composites with micron-sized filler. The calcium carbonate particles were shown to offer a large

R. H. Krämer; M. A. Raza; U. W. Gedde

2007-01-01

73

Roles of oleic acid during micropore dispersing preparation of nano-calcium carbonate particles  

Microsoft Academic Search

In the present work, nano-calcium carbonate powder was prepared by micropore dispersion method with assistance of oleic acid as surfactant. CO2 gas was dispersed into the Ca(OH)2\\/H2O slurry via a glass micropore-plate with the diameter of micropore about 20?m. To investigate the effect of oleic acid on the size of CaCO3 particles, different amount of oleic acid was added in

Jiuxin Jiang; Jie Liu; Chang Liu; Gaowen Zhang; Xinghou Gong; Jianing Liu

2011-01-01

74

Recovery of calcium carbonate from steelmaking slag and utilization for acid mine drainage pre-treatment.  

PubMed

The conversion of steelmaking slag (a waste product of the steelmaking process) to calcium carbonate (CaCO(3)) was tested using hydrochloric acid, ammonium hydroxide and carbon dioxide via a pH-swing process. Batch reactors were used to assess the technical feasibility of calcium carbonate recovery and its use for pre-treatment of acid mine drainage (AMD) from coal mines. The effects of key process parameters, such as the amount of acid (HCl/calcium molar ratio), the pH and the CO(2) flow rate were considered. It was observed that calcium extraction from steelmaking slag significantly increased with an increase in the amount of hydrochloric acid. The CO(2) flow rate also had a positive effect on the carbonation reaction rate but did not affect the morphology of the calcium carbonate produced for values less than 2 L/min. The CaCO(3) recovered from the bench scale batch reactor demonstrated effective neutralization ability during AMD pre-treatment compared with the commercial laboratory grade CaCO(3). PMID:22643421

Mulopo, J; Mashego, M; Zvimba, J N

2012-01-01

75

Improvement of Tear Trough by Monophasic Hyaluronic Acid and Calcium Hydroxylapatite  

PubMed Central

Tear trough deformities are a sign of facial aging. The anatomical base is well understood. In many patients, minimal invasive surgical procedures are useful to improve appearance. Here, the authors describe the use of monophasic hyaluronic acid dermal filler and calcium hydroxylapatite injection for correction. Forty female patients with a mean age of 50 years have been treated. On average, an improvement of one class of Hidman’s severity score could be achieved by single treatment. Mean duration of the effect was 10.1 months for hyaluronic acid and 12.8 months for calcium hydroxylapatite. Adverse effects were mild and temporary. Patients satisfaction was high (95%). PMID:25371770

2014-01-01

76

Are the anti-arrhythmic effects of omega-3 fatty acids due to modulation of myocardial calcium handling?  

PubMed Central

Both animal and clinical studies have demonstrated that omega-3 fatty acids have anti-arrhythmic properties. It has been suggested that these anti-arrhythmic effects are due to modulation of the activity of various myocardial calcium handling proteins such as ryanodine receptor (RyR), L-type calcium current and sodium/calcium exchanger. In this article, we review all the data available on the effects of omega-3 fatty acids on ventricular myocardial calcium handling. In addition we highlight some unanswered questions and discuss possible therapeutic benefits of omega-3 fatty acids. PMID:23060805

Sankaranarayanan, Rajiv; Venetucci, Luigi

2012-01-01

77

A new approach in biomimetic synthesis of calcium phosphate coatings using lactic acidNa lactate buffered body fluid solution  

E-print Network

A new approach in biomimetic synthesis of calcium phosphate coatings using lactic acid­Na lactate-SBF) contained appropriate amounts of sodium lactate (NaL) and lactic acid (HL), as well as all the other ionic

Tas, A. Cuneyt

78

Excitatory amino acids and neurodegeneration: a hypothetical role of calcium precipitation.  

PubMed

Activation of excitatory amino acid (EAA) receptors can induce neurodegeneration by two major mechanisms of excitotoxicity, one related to the influx of Na(+), Cl(-) and water, and the other to the increase in intracellular calcium concentration ([Ca(2+)](i)). Thus, acute microinjection of EAAs in several areas of the central nervous system (CNS) has been used to produce neurodegenerative models. We studied the excitotoxic pattern associated with acute microinjection of AMPA in rat hippocampus, medial septum-diagonal band of Broca (MS-DBB), prefrontal cortex and retina. In all cases progressive neuronal loss, glial reaction and development of intra- and extracellular calcium concretions were observed. However, a CNS-area differential vulnerability was revealed, as shown by the specific atrophy of MS-DBB and its limited calcification. Whether calcium deposits are a defensive mechanism against the massive increment of free cytoplasmatic calcium is discussed on the basis of ultrastructural data and previous results. PMID:10715584

Rodríguez, M J; Bernal, F; Andrés, N; Malpesa, Y; Mahy, N

2000-01-01

79

Luteolin prevents uric acid-induced pancreatic ?-cell dysfunction.  

PubMed

Elevated uric acid causes direct injury to pancreatic ?-cells. In this study, we examined the effects of luteolin, an important antioxidant, on uric acid-induced ?-cell dysfunction. We first evaluated the effect of luteolin on nitric oxide (NO) formation in uric acid-stimulated Min6 cells using the Griess method. Next, we performed transient transfection and reporter assays to measure transcriptional activity of nuclear factor (NF)-?B. Western blotting assays were also performed to assess the effect of luteolin on the expression of MafA and inducible NO synthase (iNOS) in uric acid-treated cells. Finally, we evaluated the effect of luteolin on uric acid-induced inhibition of glucose-stimulated insulin secretion (GSIS) in Min6 cells and freshly isolated mouse pancreatic islets. We found that luteolin significantly inhibited uric acid-induced NO production, which was well correlated with reduced expression of iNOS mRNA and protein. Furthermore, decreased activity of NF-?B was implicated in inhibition by luteolin of increased iNOS expression induced by uric acid. Besides, luteolin significantly increased MafA expression in Min6 cells exposed to uric acid, which was reversed by overexpression of iNOS. Moreover, luteolin prevented uric acid-induced inhibition of GSIS in both Min6 cells and mouse islets. In conclusion, luteolin protects pancreatic ?-cells from uric acid-induced dysfunction and may confer benefit on the protection of pancreatic ?-cells in hyperuricemia-associated diabetes. PMID:25050113

Ding, Ying; Shi, Xuhui; Shuai, Xuanyu; Xu, Yuemei; Liu, Yun; Liang, Xiubin; Wei, Dong; Su, Dongming

2014-07-01

80

Luteolin prevents uric acid-induced pancreatic ?-cell dysfunction  

PubMed Central

Abstract Elevated uric acid causes direct injury to pancreatic ?-cells. In this study, we examined the effects of luteolin, an important antioxidant, on uric acid-induced ?-cell dysfunction. We first evaluated the effect of luteolin on nitric oxide (NO) formation in uric acid-stimulated Min6 cells using the Griess method. Next, we performed transient transfection and reporter assays to measure transcriptional activity of nuclear factor (NF)-?B. Western blotting assays were also performed to assess the effect of luteolin on the expression of MafA and inducible NO synthase (iNOS) in uric acid-treated cells. Finally, we evaluated the effect of luteolin on uric acid-induced inhibition of glucose-stimulated insulin secretion (GSIS) in Min6 cells and freshly isolated mouse pancreatic islets. We found that luteolin significantly inhibited uric acid-induced NO production, which was well correlated with reduced expression of iNOS mRNA and protein. Furthermore, decreased activity of NF-?B was implicated in inhibition by luteolin of increased iNOS expression induced by uric acid. Besides, luteolin significantly increased MafA expression in Min6 cells exposed to uric acid, which was reversed by overexpression of iNOS. Moreover, luteolin prevented uric acid-induced inhibition of GSIS in both Min6 cells and mouse islets. In conclusion, luteolin protects pancreatic ?-cells from uric acid-induced dysfunction and may confer benefit on the protection of pancreatic ?-cells in hyperuricemia-associated diabetes. PMID:25050113

Ding, Ying; Shi, Xuhui; Shuai, Xuanyu; Xu, Yuemei; Liu, Yun; Liang, Xiubin; Wei, Dong; Su, Dongming

2014-01-01

81

Study of the chemical mechanisms of the reaction of neutralization of calcium hydroxide by phosphoric acid  

NASA Astrophysics Data System (ADS)

Calcium phosphates reported in this study, are prepared following an acido-basic reaction between phosphoric acid and calcium hydroxide. These phosphates are the brushite, tricalcium phosphate, hydroxyapatite and oxygenated apatite. The follow-up of the reaction by infra-red spectroscopy of absorption showed that the alkaline pH of calcium hydroxide solution, favours the formation of carbonated apatite, at the start of the reaction. Following the addition of phosphoric acid, the pH becomes increasingly favourable to the formation of the desired phase. The insertion of molecular oxygen in the apatitic tunnel is carried out by the use of hydrogen peroxide. The molecular oxygen rate in the apatite is then determined by volumetric analysis.

Elgadi, M.; Mejdoubi, E.; Elansari, L. L.; Essaddek, A.; Abouricha, S.; Lamhamdi, A.

2005-03-01

82

Polyhydroxycarboxylic acids as inhibitors of calcium oxalate crystal growth; Relation between inhibitory capacity and chemical structure  

NASA Astrophysics Data System (ADS)

The kinetics of crystal growth of calcium oxalate monohydrate seed crystals were investigated potentiometrically in the presence of several polyhydroxycarboxylic acids; etylenediaminetetraacetic acid, citric acid, isocitric acid, malic acid and succinic acid, and it was found that they inhibited crystal growth, except in the case of isocitric acid manifested no-effects. An apparent rate order of 2 in the presence of all the inhibitors, suggested a spiral growth mechanism. Application to a kinetic Langmuir-type model suggested that adsorption of the polyhydroxycarboxylic acids, at the active growth sites, is the cause of the reduction in the crystal growth rates. The inhibitory action of the different substances assayed was comparatively evaluated. Relations between chemical structure and inhibitory capacity were established.

Grases, F.; Millan, A.; Garcia-Raso, A.

1988-07-01

83

Palmitoleic Acid calcium salt: a lubricant and bactericidal powder from natural lipids.  

PubMed

Palmitoleic acid is a promising bactericidal agent for cleansing products with alternative bactericidal abilities. In this study, we focus on the physical and biological activity of palmitoleic acid calcium salt (C16:1 fatty acid Ca salt) because it forms via an ion-exchange reaction between palmitoleic acid and Ca ions in tap water, and remains on the skin surface during the cleansing process. Here, we prepared C16:1 fatty acid Ca salt to investigate its crystal structure and physical and bactericidal properties. The Ca salt was a plate-shaped lamellar crystalline powder with a particle diameter of several micrometers to several tens of micrometers; it exhibited significant lubricity and alternative bactericidal activity against Staphylococcus aureus (S. aureus) and Propionibacterium acnes (P. acnes). We also examined other fatty acid Ca salts prepared from lauric acid (C12:0 fatty acid), palmitic acid (C16:0 fatty acid), and oleic acid (C18:1 fatty acid). The bactericidal activities and lubricity of the fatty acid Ca salts changed with the alkyl chain length and the degree of unsaturation. The C16:1 fatty acid Ca salt exhibited the strongest selective bactericidal ability among the four investigated fatty acid Ca salts. These findings suggest that C16:1 fatty acid and its Ca salt have potential applications in cleansing and cosmetic products. PMID:25757432

Yamamoto, Yoshiaki; Kawamura, Yuki; Yamazaki, Yuki; Kijima, Tatsuro; Morikawa, Toshiya; Nonomura, Yoshimune

2015-03-01

84

IMPLICATIONS OF THE CALCIUM-ALUMINUM EXCHANGE SYSTEM FOR THE EFFECT OF ACID PRECIPITATION ON SOILS  

EPA Science Inventory

Calcium-aluminum exchange isotherms were generated for three common ion exchange equilibrium equations, and their implications relative to the probable effects of acid rainfall are examined. The equations examined were those of Gaines and Thomas (1953), Vanselow (1932), and Gapon...

85

Production of Potassium and Calcium Hydroxide, Compost and Humic Acid from Sago (Metroxylon sagu) Waste  

Microsoft Academic Search

Problem statement: Agriculture waste such as Sago Waste (SW) has a potential to cause pollution when the waste is discarded into rivers. In order to add value to SW, a study was conducted to produce potassium and calcium hydroxide, compost and Humic Acid (HA) from SW. Approach: The SW was air-dried and some grinded. The grinded SW was incinerated at

C. P. Auldry; O. H. Ahmed; A. M. Nik Muhamad; H. Mohammad Nasir; M. Jiwan

2009-01-01

86

A Laboratory Investigation of the Heterogeneous Reaction of Nitric Acid with Calcium Carbonate  

Microsoft Academic Search

Recent laboratory experiments on the heterogeneous reaction of nitric acid with calcium carbonate particles will be presented. Several different techniques are used to investigate and quantify morphology changes that occur during reaction, phase transformations, and the rate dependence of individual particles as a function of relative humidity. In addition, competitive reactions of other trace gases such as sulfur dioxide with

V. H. Grassian; B. J. Krueger; A. Preszler Prince; M. A. Young

2002-01-01

87

Effects of Calcium Deficiency on Potato Sets in Acid Soils  

Microsoft Academic Search

DURING the War, when many poor upland areas and commons in Britain were ploughed up for crop production, potatoes were commonly planted as a first crop in view of their tolerance to acid soil conditions. Many failures, however, were experienced where the soils were very strongly acid, with pH values of the order of 4.0, and it was shown that

T. Wallace; E. J. Hewitt

1948-01-01

88

Preventive Effect of Phytic Acid on Isoproterenol-Induced Cardiotoxicity in Wistar Rats  

PubMed Central

This study was aimed to evaluate the preventive role of phytic acid on membrane bound enzymes such as sodium potassium- dependent adenosine triphosphatase (Na+ /K+ ATPase), calcium-dependent adenosine triphosphatase (Ca2+ ATPase) and magnesium- dependent adenosine triphosphatase (Mg2+ ATPase) and glycoproteins such as hexose, hexosamine, fucose and sialic acid in isoproterenol (ISO)-induced myocardial infarction (MI) in rats. Male albino Wistar rats were pretreated with phytic acid (25 and 50 mg/kg, respectively) for a period of 56 days. After the treatment period, ISO (85 mg/kg) was subcutaneously injected to rats at an interval of 24 h for 2 days. ISO-induced rats showed a significant decrease in the activity of Na+ /K+ ATPase and increase in the activities of Ca2+ and Mg2+ ATPase in the heart and a significant (P<0.05) increase in the levels of glycoproteins in serum and the heart were also observed in ISO-induced rats. Pretreatment with phytic acid for a period of 56 days exhibited a significant (P<0.05) effect and altered these biochemical parameters positively in ISO-induced rats. Thus, our study shows that phytic acid has cardioprotective role in ISO-induced MI in rats.

Brindha, E.; Rajasekapandiyan, M.

2015-01-01

89

Intra-Arterial Calcium Gluconate Treatment After Hydrofluoric Acid Burn of the Hand  

SciTech Connect

Hydrofluoric acid (HF) is a colorless corrosive acid used in different industrial branches. Exposure to HF typically results from spills, and most often the hand or fingers are involved. Tissue damage through cutaneous HF exposure occurs through corrosive burns due to the free hydrogen ions and through skin penetration of the fluoride ions, causing a depletion of calcium in the deep tissue layers, ultimately leading to cell death and tissue necrosis. Treatment of HF burns consists of thoroughly flushing the exposed area with water and applying calcium gluconate gel to the skin. If topical treatment does not suffice, subcutaneous injections, as well as intravascular-both intravenous and intra-arterial-calcium gluconate therapy, have been advocated. We report for the first time a case of HF burn of the hand and digits associated with vasospasm. Pain and vasospasm were successfully treated by repeated intra-arterial calcium gluconate injection. We conclude that intra-arterial calcium gluconate injection is a successful and well-tolerated therapy for HF burn associated with Raynaud's syndrome. Intra-arterial injection allows for well-controlled delivery of therapy as well as assessment of the vascular status.

Thomas, D., E-mail: daniel.thomas@ukb.uni-bonn.de; Jaeger, U. [Radiologische Universitaetsklinik, Universitaet Bonn (Germany); Sagoschen, I. [Klinikum der Johannes Gutenberg Universitaet, Poison Control Center, Medizinische Klinik und Poliklinik II (Germany); Lamberti, C. [Universitaet Bonn, Medizinische Klinik und Poliklinik I (Germany); Wilhelm, K. [Radiologische Universitaetsklinik, Universitaet Bonn (Germany)

2009-01-15

90

Influence of maleic acid copolymers on calcium orthophosphates crystallization at low temperature  

NASA Astrophysics Data System (ADS)

The goal of this study was to investigate the maleic acid copolymers role on calcium orthophosphates crystallization at low temperature. In this respect, two maleic acid copolymers with different structures [poly(sodium maleate-co-vinyl acetate) and poly(sodium maleate-co-methyl methacrylate)] were used. The syntheses of the calcium orthophosphates in the absence and in the presence of the copolymers were performed through the wet chemical method using calcium nitrate, ammonium dihydrogen phosphate and ammonium hydroxide as reactants. The syntheses were monitored in situ by potentiometric and conductometric measurements. To ensure the transformation of less thermodynamically stable calcium orthophosphates into more stable forms, the samples were aged 30 days in mother solutions, at room temperature. The presence of the copolymers in the final products was evidenced by FTIR spectroscopy and thermogravimetric analysis. Scanning and transmission electron microscopy and laser light scattering measurements gave information about the composites morphology and the size of the formed structures. X-ray diffraction evidenced that, as a function of comonomer structure and of copolymer concentration, the products could contain hydroxyapatite with low crystallinity, calcium-deficient or carbonated hydroxyapatite. At high concentration of poly(sodium maleate-co-methyl methacrylate) the transformation of brushite into apatitic structures was inhibited.

Pelin, Irina M.; Popescu, Irina; Suflet, Dana M.; Aflori, Magdalena; Bulacovschi, Victor

2013-08-01

91

Longitudinal Analysis of Calcium Supplementation Preventing Bone Mass Loss in Females  

Microsoft Academic Search

Calcium is an important nutrient for metabolism of bones (Greer & Krebs, 2006). This study hypothesizes that consuming calcium supplements for twenty years decreases women’s risk of developing osteoporosis. A longitudinal study of 100 women in Portland, Oregon consists of five different conditions where all except the nutritional group takes 1000mg calcium supplements daily for 20 years. Conditions for the

Piilani Nicola

2012-01-01

92

IMPACT OF AROMATIC VERSUS BRANCHED-CHAIN AMINO ACIDS ON CALCIUM EXCRETION, ABSORPTION, AND BONE TURNOVER – POTENTIAL ROLE OF THE CALCIUM SENSOR RECEPTOR  

Technology Transfer Automated Retrieval System (TEKTRAN)

Aromatic amino acids (AAAs), but not branched-chain amino acids (B-CAAs), bind to the calcium sensor receptor (CaSR) in renal tissue and thus AAAs may have a greater calciuric action than B-CAAs (1). This study was done to determine and compare the effects of increasing intake of these two types of ...

93

Hexavalent chromium damages chamomile plants by alteration of antioxidants and its uptake is prevented by calcium.  

PubMed

Toxicity of low (3?M) and high (60 and 120?M) concentrations of hexavalent chromium/Cr(VI) in chamomile plants was studied. Fluorescence staining confirmed reduction of Cr(VI) to Cr(III). Cr was mainly accumulated in the roots with translocation factor <0.007. Notwithstanding this, both shoots and roots revealed increase in oxidative stress and depletion of glutathione, total thiols, ascorbic acid and activities of glutathione reductase and partially ascorbate peroxidase mainly at 120?M Cr. Though some protective mechanisms were detected (elevation of nitric oxide, enhancement of GPX activity and increase in phenols and lignin), this was not sufficient to counteract the oxidative damage. Consequently, soluble proteins, tissue water content and biomass production were considerably depleted. Surprising increase in some mineral nutrients in roots (Ca, Fe, Zn and Cu) was also detected. Subsequent experiment confirmed that exogenous calcium suppressed oxidative symptoms and Cr uptake but growth of chamomile seedlings was not improved. Alteration of naturally present reductants could be a reason for Cr(III) signal detected using specific fluorescence reagent: in vitro assay confirmed disappearance of ascorbic acid in equimolar mixture with dichromate (>96% at pH 4 and 7) while such response of glutathione was substantially less visible. PMID:24727012

Ková?ik, Jozef; Babula, Petr; Hedbavny, Josef; Klejdus, Bo?ivoj

2014-05-30

94

[Long-term effect of calcium carbonate containing antacids on basally and peptone-stimulated hydrochloric acid secretion].  

PubMed

Basal and meal-stimulated gastric acid secretion was measured before and after a 3-week-period of regular consumption of a calcium carbonate-containing antacid with 6 therapeutic doses per day in normal healthy volunteers. Furthermore the effect of a single large dose of 2000 mg calcium ions was studied on meal-stimulated gastric acid secretion before and after this period. The results suggest that (1) even a large single dose of calcium ions seems to have no major effect on meal-stimulated gastric acid secretion and (2) chronic consumption of calcium carbonate containing antacids over a 3-week-period does not change basal- and meal-stimulated gastric acid secretion in healthy volunteers nor does it increase the response to 2 g calcium ions. PMID:40853

Lux, G; Waldherr, P A; Schmack, B; Rösch, W

1979-10-01

95

Effects of calcium salts of acidic monomers on mineral induction of phosphoprotein immobilized to agarose beads.  

PubMed

The aim of this study is to evaluate the mineralizing potential of acidic monomers and their calcium salts for mineralization, using an in vitro mineral induction model. Phosvitin (PV) was used as a model phosphoprotein in this study. PV was immobilized on agarose beads with divinyl sulfone. Five aliquots of agarose-immobilized PV, acidic monomers, and their calcium salts were incubated in mineralizing solution at various concentrations. The PV beads and acidic monomers were incubated at 37°C. Samples were taken at several time points during the incubation. Then, the agarose beads were analyzed for bound calcium by atomic absorption spectrometry. The mineral formed on the agarose beads was identified as an apatite by microarea X-ray diffraction. Additionally, the specimens were observed using scanning electron microscopy (SEM). Mineral induction time decreased with increasing solution saturation. 4-METCa salt [calcium salt of 4-methacryloxyethyl trimellitate (CMET)] significantly reduced the mineral induction time. Using these data, the interfacial tension for mineral induction of PV and CMET was determined to be 90.1 and 92.7 ergs/cm(2), respectively. The mineral induced in each specimen after incubation for 24 h was identified by its X-ray diffraction pattern as apatite. SEM observation showed that lath-shaped crystals were formed on the surfaces of the CMET. We conclude that CMET could play a role in dentin remineralization. PMID:22623052

Ito, Shuichi; Iijima, Masahiro; Motai, Fumiko; Mizoguchi, Itaru; Saito, Takashi

2012-10-01

96

Characterization of modified calcium-silicate cements exposed to acidic environment  

SciTech Connect

Portland cement which is used as a binder in concrete in the construction industry has been developed into a biomaterial. It is marketed as mineral trioxide aggregate and is used in dentistry. This material has been reported to be very biocompatible and thus its use has diversified. The extended use of this material has led to developments of newer versions with improved physical properties. The aim of this study was to evaluate the effect of acidic environments found in the oral cavity on fast setting calcium silicate cements with improved physical properties using a combination of techniques. Two fast setting calcium silicate cements (CSA and CFA) and two cement composites (CSAG and CFAG) were assessed by subjecting the materials to lactic acid/sodium lactate buffer gel for a period of 28 days. At weekly intervals the materials were viewed under the tandem scanning confocal microscope (TSM), and scanning electron microscope (SEM). The two prototype cements exhibited changes in their internal chemistry with no changes in surface characteristics. Since the changes observed were mostly sub-surface evaluation of surface characteristics of cement may not be sufficient in the determination of chemical changes occurring. - Research Highlights: {yields} An acidic environment affects modified fast setting calcium silicate-based cements. {yields} No surface changes are observed in acidic environment. {yields} An acidic environment causes sub-surface changes in the material chemistry which are only visible in fractured specimens. {yields} A combination of techniques is necessary in order to evaluate the chemical changes occurring.

Camilleri, Josette, E-mail: josette.camilleri@um.edu.mt

2011-01-15

97

Effects of acid deposition on calcium nutrition and health of Southern Appalachian spruce fir forests  

SciTech Connect

The role of acid deposition in the health of spruce fir forests in the Southern Appalachian Mountains has been investigated by a wide variety of experimental approaches during the past 10 years. These studies have proceeded from initial dendroecological documentation of altered growth patterns of mature trees to increasingly more focused ecophysiological research on the causes and characteristics of changes in system function associated with increased acidic deposition. Field studies across gradients in deposition and soil chemistry have been located on four mountains spanning 85 km of latitude within the Southern Appalachians. The conclusion that calcium nutrition is an important component regulating health of red spruce in the Southern Appalachians and that acid deposition significantly reduces calcium availability in several ways has emerged as a consistent result from multiple lines or research. These have included analysis of trends in wood chemistry, soil solution chemistry, foliar nutrition, gas exchange physiology, root histochemistry, and controlled laboratory and field studies in which acid deposition and/or calcium nutrition has been manipulated and growth and nutritional status of saplings or mature red spruce trees measured. This earlier research has led us to investigate the broader implications and consequences of calcium deficiency for changing resistance of spruce-fir forests to natural stresses. Current research is exploring possible relationships between altered calcium nutrition and shifts in response of Fraser fir to insect attack by the balsam wooly adelgid. In addition, changes in wood ultrastructural properties in relation to altered wood chemistry is being examined to evaluate its possible role in canopy deterioration, under wind and ice stresses typical of high elevation forests.

McLaughlin, S.B.; Wullschleger, S. [Oak Ridge National Lab., TN (United States); Stone, A. [Univ. of Tennessee, Knoxville, TN (United States); Wimmer, R. [Austrian Agricultural Univ., Vienna (Austria); Joslin, J.D.

1995-02-01

98

[The prevention of the development of myocardial contracture in the "calcium paradox" by action on Na-Ca metabolism].  

PubMed

The effect of artificial high sodium gradient on the rate of the myocardium contracture development during "calcium paradox" was studied in the experiments on the isolated heart of Langendorf-perfused rats. It is stated that artificial creation of a high sodium gradient decreases the rate of the myocardium contracture development. Exogenous nucleotides, activators of Na, K-ATPase, and their precursors intensified the protective action of the hypersodium medium. Phosphocreatine (100 mmol/l) had no protective effect during the "calcium paradox". However, under conditions of the high sodium gradient phosphocreatine efficiently prevented development of the contracture during the "calcium paradox". It is important to note that under analogous conditions creation of high osmosity of the solution adding 12 mmol/l of saccharose does not protect the heart from development of the myocardium contracture. PMID:1286697

Alabovski?, V V; Vinokurov, A A

1992-01-01

99

The Calcium-Sensing Receptor Promotes Urinary Acidification to Prevent Nephrolithiasis  

PubMed Central

Hypercalciuria increases the risk for urolithiasis, but renal adaptive mechanisms reduce this risk. For example, transient receptor potential vanilloid 5 knockout (TPRV5?/?) mice lack kidney stones despite urinary calcium (Ca2+) wasting and hyperphosphaturia, perhaps as a result of their significant polyuria and urinary acidification. Here, we investigated the mechanisms linking hypercalciuria with these adaptive mechanisms. Exposure of dissected mouse outer medullary collecting ducts to high (5.0 mM) extracellular Ca2+ stimulated H+-ATPase activity. In TRPV5?/? mice, activation of the renal Ca2+-sensing receptor promoted H+-ATPase–mediated H+ excretion and downregulation of aquaporin 2, leading to urinary acidification and polyuria, respectively. Gene ablation of the collecting duct-specific B1 subunit of H+-ATPase in TRPV5?/? mice abolished the enhanced urinary acidification, which resulted in severe tubular precipitations of Ca2+-phosphate in the renal medulla. In conclusion, activation of Ca2+-sensing receptor by increased luminal Ca2+ leads to urinary acidification and polyuria. These beneficial adaptations facilitate the excretion of large amounts of soluble Ca2+, which is crucial to prevent the formation of kidney stones. PMID:19470676

Renkema, Kirsten Y.; Velic, Ana; Dijkman, Henry B.; Verkaart, Sjoerd; van der Kemp, Annemiete W.; Nowik, Marta; Timmermans, Kim; Doucet, Alain; Wagner, Carsten A.; Bindels, René J.

2009-01-01

100

Steel corrosion protection by means of alkyd paints pigmented with calcium acid phosphate  

SciTech Connect

The use of classic anticorrosive pigments is becoming more and more restricted by increasing environmental concerns; they are gradually being replaced by zinc phosphate and related compounds. Other anticorrosive pigments such as surface-exchanged silicas were also proposed. The object of this research is to study the anticorrosive properties of calcium acid phosphate as an inhibitive pigment, introducing a careful selection of complementary pigments in order to achieve an efficient anticorrosive protection. Several alkyd paints were prepared and evaluated through accelerated and electrochemical tests. The nature of the passive film formed was also studied. Paint containing zinc oxide and calcium carbonate (50/50) as complementary pigments showed the best performance in the salt spray test. Zinc oxide and calcium carbonate decreased film permeability and improved steel passivation. The passive film was composed of ferric oxyhydroxide, the pores of which became plugged by ferric phosphate.

Amo, B. del; Romagnoli, R.; Vetere, V.F. [CIC-CONICET, La Plata (Argentina)

1999-06-01

101

L-Ascorbic acid and L-galactose are sources for oxalic acid and calcium oxalate in Pistia stratiotes.  

PubMed

Axenic Pistia stratiotes L. plants were pulse-chase labeled with [14C]oxalic acid, L[1-14C]ascorbic acid, L-6-14C]ascorbic acid, D-[1-14C]erythorbic acid, L-[1-14C]galactose, or [1-14C]glycolate. Specific radioactivities of L-ascorbic acid (AsA), free oxalic acid (OxA) and calcium oxalate (CaOx) in labeled plants were compared. Samples of leaf tissue were fixed for microautoradiography and examined by confocal microscopy. Results demonstrate a biosynthetic role for AsA as precursor of OxA and its crystalline deposition product, CaOx, in idioblast cells of P. stratiotes and support the recent discovery of Wheeler, Jones and Smirnoff (Wheeler, G.L., Jones M.A., & Smirnoff, N. (1998). The biosynthetic pathway of vitamin C in higher plants. Nature, 393, 365-369) that L-galactose is a key intermediate in the conversion of D-glucose to AsA in plants. D-[1-14C]erythorbic acid (a diastereomeric analog of AsA) is utilized also by P. stratiotes as a precursor of OxA and its calcium salt deposition product in idioblasts. Labeled OxA is rapidly incorporated into CaOx in idioblasts, but microautoradiography shows there is also significant incorporation of carbon from OxA into other components of growing cells, contrary to the dogma that OxA is a relatively stable end product of metabolism. Glycolate is a poor substrate for synthesis of OxA and CaOx formation, further establishing AsA as th immediate precursor in the synthesis of OxA used for calcium precipitation in crystal idioblasts. PMID:10731019

Keates, S E; Tarlyn, N M; Loewus, F A; Franceschi, V R

2000-02-01

102

Interactions of calcium and fulvic acid at the goethite-water interface  

NASA Astrophysics Data System (ADS)

Interactions of calcium and fulvic acid (Strichen ) with the surface of goethite were studied with batch and titration experiments. The mutual influence of the interactions on the adsorption of fulvic acid, calcium ions and protons were examined. Adsorption of the fulvic acid to goethite decreased with increase in pH (pH range 3-11). Addition of Ca (1.0 mM) at intermediate and high pH significantly enhanced the adsorption of fulvic acid. Compared to the adsorption to pure goethite, the presence of fulvic acid enhanced the adsorption of Ca significantly. In comparison to the simple linear sum of Ca bound to fulvic acid and goethite, the interactions between goethite and fulvic acid led to a reduced adsorption of Ca at low pH and an enhanced adsorption at high pH. With the adsorption of fulvic acid, protons were released at low pH and coadsorbed at high pH. When Ca was added, fewer protons were released at low pH and fewer coadsorbed at high pH. The experimental results can be adequately described using a surface complexation model, the Ligand and Charge Distribution (LCD) model, in which the CD-MUSIC model for ion adsorption to mineral oxides and the NICA model for ion binding to humics are integrated. In the model calculations, adequate descriptions of the ternary system data (Ca-fulvic acid-goethite) were obtained with parameters derived from three binary systems (fulvic acid-goethite, Ca-goethite and Ca-fulvic acid) without further adjustment. The model calculations suggest that the interactions between Ca and fulvic acid at the surface of goethite are mainly due to the electrostatic effects.

Weng, Li Ping; Koopal, Luuk K.; Hiemstra, Tjisse; Meeussen, Johannes C. L.; Van Riemsdijk, Willem H.

2005-01-01

103

Recrystallization of calcium sulfate in phosphoric acid solutions; batchwise operation  

NASA Astrophysics Data System (ADS)

A model is presented for the solvent mediated batchwise recrystallization of hemihydrate into dehydrate. The model takes into account the rates of dissolution of hemihydrate and of growth of gypsum. These rates result from the driving forces (under- and supersaturation) that are influenced by temperature and acid concentrations, and from the rate constants, which are mainly affected by impurities. Secondary nucleation can be neglected with respect to the observed recrystallization rates. The presented model can also be applied more generally.

Witkamp, G. J.; Seckler, M. M.; Bruinsma, O. S. L.; van Rosmalen, G. M.

1990-01-01

104

Procedure for the study of acidic calcium phosphate precursor phases in enamel mineral formation.  

PubMed

Considerable evidence suggests that an acidic calcium phosphate, such as octacalcium phosphate (OCP) or brushite, is involved as a precursor in enamel and other hard tissue formation. Additionally, there is in vitro evidence suggesting that fluoride accelerates and magnesium inhibits the hydrolysis of OCP to hydroxyapatite (OHAp). As the amount of OCP or brushite in enamel cannot be measured directly in the presence of an excess of hydroxyapatite, a procedure was developed that allows for their indirect in vivo quantification as pyrophosphate. This permits study of the effects of fluoride and magnesium ions on enamel mineral synthesis. Rat incisor calcium phosphate was labeled by intraperitoneal injection of NaH2(32)PO4. The rats were then subjected to various fluoride and magnesium treatments with subcutaneous implanted osmotic pumps. They were then killed at predetermined intervals; the nascent sections of the incisors were collected, cleaned, and pyrolyzed at 500 degrees C for 48 hours to convert acidic calcium phosphates to calcium pyrophosphate; the pyrophosphate was separated from orthophosphate by anion-exchange chromatography; and the resulting fractions were counted by liquid scintillation spectrometry. The activities of the pyro- and orthophosphate fractions were used to calculate the amount of acidic calcium phosphate present in the nascent mineral. The results demonstrated that the percentage of radioactive pyrophosphate in nascent incisors decreased with time, with increasing serum F- concentration, and with decreasing serum magnesium content. The technique described here should prove to be a powerful new tool for studying the effects of various agents on biological mineral formation. PMID:1315187

Siew, C; Gruninger, S E; Chow, L C; Brown, W E

1992-02-01

105

[Calcium antagonists: current and future applications based on new evidence. The mechanisms on lowering serum uric acid level by calcium channel blockers].  

PubMed

In hypertensive subjects, their serum uric acid levels tend to be higher because of decreasing urinary secretion or overproduction of uric acid. Among calcium channel blockers (CCBs) , long acting nifedipine and cilnidipine reveal serum uric acid lowering action. They decrease the production of uric acid precursor in skeletal muscles under anaerobic condition induced by hypertension or insulin resistance. Hyperuricemia is considered to be a risk factor of not only gout but also renal and cardiovascular diseases, thus, it is important to use CCBs without adverse effect on uric acid metabolisms. PMID:20048433

Mizuta, Einosuke; Hamada, Toshihiro; Igawa, Osamu; Shigemasa, Chiaki; Hisatome, Ichiro

2010-01-01

106

Morphological modifications of electrodeposited calcium phosphate coatings under amino acids effect  

NASA Astrophysics Data System (ADS)

Calcium phosphate coatings are synthesized on titanium alloy (Ti6Al4V) substrates by pulsed electrodeposition. This work aims to observe the morphological modifications of the coating when an amino acid is added to the electrolytic solution used in the process. The effects of two amino acids (glutamic acid and aspartic acid) are studied at a low and a high concentration. The coating morphology is observed at a nanometer scale by field emission gun-scanning electron microscopy (FEG-SEM). The structural characterization of the coating is performed by Fourier transformed infrared spectroscopy (FT-IR), Raman spectroscopy and X-ray diffraction (XRD). Moreover, corrosion measurements of the prosthetic surfaces are carried out by potentiodynamic polarization experiments in a physiological solution named Dulbecco's modified eagle medium (DMEM). The results show that the addition of an amino acid to the electrolytic solution leads to the decrease of the size of the crystallites which compose the prosthetic calcium phosphate coating that becomes denser and less porous than the coatings obtained without amino acid. Consequently, the corrosion behavior of the prosthetic material immersed in DMEM is improved.

Drevet, R.; Lemelle, A.; Untereiner, V.; Manfait, M.; Sockalingum, G. D.; Benhayoune, H.

2013-03-01

107

Interaction of organic compounds with calcium carbonate--III. Amino acid composition of sorbed layers  

Microsoft Academic Search

Nitrogenous organic compounds in sorbed surface layers and in calcified organic matter associated with calcium carbonate sediment particles consist of 40-50% amino acids, 2% amino sugars and 25% ammonia. In grain size classes > 20 m these compounds are mainly contained in the calcified protein of carbonate secreting organisms but with smaller grain sizes--and consequently increased specific surface area--they are

Peter J. Müller; Erwin Suess

1977-01-01

108

Biocompatibility and degradation of poly(DL-lactic-co-glycolic acid)\\/calcium phosphate cement composites  

Microsoft Academic Search

Injectable calcium phosphate (Ca-P) cement materials exhibit favorable osteocompatible behavior but are resorbed slowly because of a lack of a bone ingrowth-enabling macroporosity. In this study, poly(DL-lactic-co-glycolic acid) (PLGA) microparticles (average size 66 +\\/- 25 microm) were incorporated into Ca-P cement to obtain a macroporous Ca-P cement scaffold after PLGA hydrolysis in vivo. Preset PLGA\\/Ca-P cement composite discs of various

P. Quinten Ruhé; Elizabeth L. Hedberg; Nestor Torio Padron; Paul H. M. Spauwen; John A. Jansen; Antonios G. Mikos

2005-01-01

109

Effects of calcium soaps of fatty acids on postpartum reproductive function in beef  

Microsoft Academic Search

ABSTRACT Twelve multiparous Simmental cows (584 kg) were used to determine the influence of calcium soaps of fatty acids (CSFA) incorporated in a range supplement on postpartum reproductive characteristics. Cows were assigned randomly,to receive a control [C; containin grain sorghum,(GS) and soybean meal (SBM)] or CSFA-based (containing were individually , fed CSFA although plasma triglyceride concentrations were similar between treatments.

R. B. Hightshoe; R. C. Cochran; L. R. Corah; G. H. Kiracofe; D. L. Harmon; R. C. Perry

110

Preparation of ?-Ca 3(PO 4) 2 bioceramic powder from calcium carbonate and phosphoric acid  

Microsoft Academic Search

When preparing ?-tricalcium phosphate (?-TCP) with Ca(NO3)2 or Ca(OH)2 as the raw materials, because of the problem of filtering, it is difficult to industrialize traditional methods. In this paper, ?-TCP was prepared with calcium carbonate and phosphoric acid. According to XRD spectrum, the precursor of this system is octacalcium phosphate (OCP) [Ca8H2(PO4)6·5H2O] instead of non-stoichiometric hydroxyapatite (HA) obtained from traditional

Yun Zhang; Guangfu Yin; Shifu Zhu; Dali Zhou; Yuehua Wang; Yong Li; Lin Luo

2005-01-01

111

Preparation of poly(lactic acid)\\/siloxane\\/calcium carbonate composite membranes with antibacterial activity  

Microsoft Academic Search

A poly(lactic acid) (PLA)\\/siloxane\\/calcium carbonate composite membrane containing mercapto groups (PSC-SH) with antibacterial ability and excellent bone-forming ability was prepared using 3-mercaptopropyltrimethoxysilane for application in guided bone regeneration. Mercapto groups were reported to adsorb silver ions, which are well known to show antibacterial activity. Ionic silicon species were reported to stimulate the proliferation of osteoblasts. A PSC-SH membrane with a

Shingo Tokuda; Akiko Obata; Toshihiro Kasuga

2009-01-01

112

Heterogeneous reactions of gaseous methanesulfonic acid with calcium carbonate and kaolinite particles  

Microsoft Academic Search

Heterogeneous reactions of gaseous methanesulfonic acid (MSA) with calcium carbonate (CaCO3) and kaolinite particles at room temperature were investigated using diffuse reflectance infrared Fourier transform spectroscopy\\u000a (DRIFTS) and ion chromatography (IC). Methanesulfonate (MS?) was identified as the product in the condensed phase, in accordance with the product of the reaction of gaseous MSA with\\u000a NaCl and sea salt particles. When

MingJin Tang; MengQiu Li; Tong Zhu

2010-01-01

113

Characterization of uronic-acid-rich inhibitor of calcium oxalate crystallization isolated from rat urine  

Microsoft Academic Search

Human urine contains several macromolecules which inhibit calcium oxalate crystallization. Uronic-acid-rich protein (UAP), a glycoprotein with a molecular weight of approximately 35 kDa, is one such inhibitor. Here we report the characterization of UAP extracted from rat urine using three chromatographic steps including diethylaminoethanol (DEAE)-Sephacel, Sephacryl S-300 and Mono Q column and compare it with human UAP. The molecular weight

F. Atmani; S. R. Khan

1995-01-01

114

CITRIC ACID AS A SET RETARDER FOR CALCIUM ALUMINATE PHOSPHATE CEMENTS.  

SciTech Connect

Citric acid added as set retarder significantly contributed to enhancing the setting temperature and to extending the thickening time of a calcium aluminate phosphate (CaP) geothermal cement slurry consisting of calcium aluminate cement (CAC) as the base reactant and sodium polyphosphate (NaP) solution as the acid reactant. The set-retarding activity of citric acid was due to the uptake of Ca{sup 2+} ions from the CAC by carboxylic acid groups within the citric acid. This uptake led to the precipitation of a Ca-complexed carboxylate compound as a set-retarding barrier layer on the CAC grains' surfaces. However, this barrier layer was vulnerable to disintegration by the attack of free Ca{sup 2+} ions from CAC, and also to degradation at elevated temperature, thereby promoting the generation of exothermic energy from acid-base reactions between the CAC and NaP after the barrier was broken. The exothermic reaction energy that was promoted in this way minimized the loss in strength of the citric acid-retarded cement. The phase composition assembled in both retarded and non-retarded cements after autoclaving at 180 C encompassed three reaction products, hydroxyapatite (HOAp), hydrogrossular and boehmite, which are responsible for strengthening the autoclaved cement. The first two reaction products were susceptible to reactions with sulfuric acid and sodium sulfate to form crystalline bassanite scale as the corrosion product. The boehmite phase possessed a great resistance to acid and sulfate. Although the bassanite scales clinging to the cement's surfaces were the major factor governing the loss in weight, they served in protecting the cement from further acid- and sulfate-corrosion until their spallation eventually occurred. Nevertheless, the repetitive processes of HOAp and hydrogrossular {yields} bassanite {yields} spallation played an important role in extending the useful lifetime of CaP cement in a low pH environment at 180 C.

SUGAMA,T.; BROTHERS, L.E.

2005-01-01

115

Effects of N,N,N',N'-ethylenediaminetetramethylene phosphonic acid and 1-hydroxyethylidene-1,1-bisphosphonic acid on calcium absorption, plasma calcium, longitudinal bone growth, and bone histology in the growing rat.  

PubMed

Phosphonate compounds are of considerable interest because of their effects on biological mineralization and mineral metabolism. The effects of graded doses given parenterally or orally of N,N,N',N'-ethylenediamine tetramethylene phosphonic acid (EDITEMPA) on calcium absorption, plasma calcium, endochondral bone elongation, and osseous tissue histology of rats were determined. In some experiments 1-hydroxyethylidene-1,1-bisphosphonic acid (HEBP) was included for comparison. Given sc for 7 days, EDITEMPA caused dose-related decreases in net weight gain, intestinal calcium absorption, and longitudinal bone growth. There were also increases in total plasma calcium concentrations and excess osteoid accumulation in bone. When EDITEMPA was given po for 7, 28, or 90 days, few changes in osseous tissues were observed and then only at the highest dose (333 mg/kg/day). An equivalent dose of HEBP caused substantial changes in osseous tissues and calcium parameters. PMID:3919462

Miller, S C; Jee, W S; Woodbury, D M; Kemp, J W

1985-02-01

116

Endurance exercise training normalizes repolarization and calcium-handling abnormalities, preventing ventricular fibrillation in a model of sudden cardiac death  

PubMed Central

The risk of sudden cardiac death is increased following myocardial infarction. Exercise training reduces arrhythmia susceptibility, but the mechanism is unknown. We used a canine model of sudden cardiac death (healed infarction, with ventricular tachyarrhythmias induced by an exercise plus ischemia test, VF+); we previously reported that endurance exercise training was antiarrhythmic in this model (Billman GE. Am J Physiol Heart Circ Physiol 297: H1171–H1193, 2009). A total of 41 VF+ animals were studied, after random assignment to 10 wk of endurance exercise training (EET; n = 21) or a matched sedentary period (n = 20). Following (>1 wk) the final attempted arrhythmia induction, isolated myocytes were used to test the hypotheses that the endurance exercise-induced antiarrhythmic effects resulted from normalization of cellular electrophysiology and/or normalization of calcium handling. EET prevented VF and shortened in vivo repolarization (P < 0.05). EET normalized action potential duration and variability compared with the sedentary group. EET resulted in a further decrement in transient outward current compared with the sedentary VF+ group (P < 0.05). Sedentary VF+ dogs had a significant reduction in repolarizing K+ current, which was restored by exercise training (P < 0.05). Compared with controls, myocytes from the sedentary VF+ group displayed calcium alternans, increased calcium spark frequency, and increased phosphorylation of S2814 on ryanodine receptor 2. These abnormalities in intracellular calcium handling were attenuated by exercise training (P < 0.05). Exercise training prevented ischemically induced VF, in association with a combination of beneficial effects on cellular electrophysiology and calcium handling. PMID:23042911

Bonilla, Ingrid M.; Belevych, Andriy E.; Sridhar, Arun; Nishijima, Yoshinori; Ho, Hsiang-Ting; He, Quanhua; Kukielka, Monica; Terentyev, Dmitry; Terentyeva, Radmila; Liu, Bin; Long, Victor P.; Györke, Sandor; Billman, George E.

2012-01-01

117

Synthesis, characterization and cation adsorption of p-aminobenzoic acid intercalated on calcium phosphate  

SciTech Connect

Graphical abstract: Scanning electron microscopy photographs of calcium phosphate (a) and intercalated with p-aminobenzoic acid (b). Highlights: ? Calcium phosphate was intercalated with p-aminobenzoic acid. ? Guest molecule contains nitrogen and oxygen atoms from amine and carboxylic groups. ? These basic centers are potentially useful for cation coordination in ethanol solution. ? Crystal morphology of compounds is lamellar, it agrees with expected structural characteristics. -- Abstract: Crystalline lamellar calcium phosphate retained 4-aminobenzoic acid inside its cavity without leaching. The intense infrared bands in the 1033 and 1010 cm{sup ?1} interval confirmed the presence of the phosphonate groups attached to the inorganic layer, with sharp and intense peaks in X-ray diffraction patterns, which gave basal distances of 712 and 1578 pm for the original and the intercalated compounds, respectively. Solid-state {sup 31}P nuclear magnetic resonance spectra presented only one peak for the phosphate groups attached to the main inorganic polymeric structure near ?2.4 ppm. The adsorption isotherms from ethanol gave the maximum adsorption capacities of 6.44 and 3.34 mmol g{sup ?1} for nickel and cobalt, respectively, which stability constant and distribution coefficient followed Co > Ni.

Silva, Camila F.N. [Departamento de Química, Universidade Estadual de Maringá, Av. Colombo, 5790, 87020-900 Maringá, PR (Brazil)] [Departamento de Química, Universidade Estadual de Maringá, Av. Colombo, 5790, 87020-900 Maringá, PR (Brazil); Lazarin, Angélica M., E-mail: amlazarin2@uem.br [Departamento de Química, Universidade Estadual de Maringá, Av. Colombo, 5790, 87020-900 Maringá, PR (Brazil); Sernaglia, Rosana L.; Andreotti, Elza I.S. [Departamento de Química, Universidade Estadual de Maringá, Av. Colombo, 5790, 87020-900 Maringá, PR (Brazil)] [Departamento de Química, Universidade Estadual de Maringá, Av. Colombo, 5790, 87020-900 Maringá, PR (Brazil)

2012-06-15

118

Arachidonic acid induces brain endothelial cell apoptosis via p38-MAPK and intracellular calcium signaling.  

PubMed

Arachidonic acid (AA), a bioactive fatty acid whose levels increase during neuroinflammation, contributes to cerebral vascular damage and dysfunction. However, the mode of injury and underlying signaling mechanisms remain unknown. Challenge of primary human brain endothelial cells (HBECs) with AA activated a stress response resulting in caspase-3 activation, poly(ADP-ribose) polymerase cleavage, and disruption of monolayer integrity. AA also induced loss of mitochondrial membrane potential and cytochrome c release consistent with activation of intrinsic apoptosis. HBEC stimulation with AA resulted in sustained p38-MAPK activation and subsequent phosphorylation of mitogen-activated protein kinase activated protein-2 (MAPKAP-2) kinase and heat shock protein-27 (Hsp27). Conversely, other unsaturated and saturated fatty acids had no effect. Pharmacological and RNA interference-mediated p38? or p38? suppression abrogated AA signaling to caspase-3 and Hsp27, suggesting involvement of both p38 isoforms in AA-induced HBEC apoptosis. Hsp27 silencing also blocked caspase-3 activation. AA stimulated intracellular calcium release, which was attenuated by inositol 1,4,5-trisphosphate (IP3) receptor antagonists. Blockade of intracellular calcium release decreased caspase-3 activation, but had no effect on AA-induced p38-MAPK activation. However, inhibition of p38-MAPK or blockade of intracellular calcium mobilization abrogated AA-induced cytochrome c release. AA-induced caspase-3 activation was abrogated by pharmacological inhibition of lipooxygenases. These findings support a previously unrecognized signaling cooperation between p38-MAPK/MAPKAP-2/Hsp27 and intracellular calcium release in AA-induced HBEC apoptosis and suggest its relevance to neurological disorders associated with vascular inflammation. PMID:24802256

Evans, Justin; Ko, YooSeung; Mata, Wilmer; Saquib, Muhammad; Eldridge, Joel; Cohen-Gadol, Aaron; Leaver, H Anne; Wang, Shukun; Rizzo, Maria Teresa

2015-03-01

119

Heat stability and acid gelation properties of calcium-enriched reconstituted skim milk affected by ultrasonication.  

PubMed

The aggregation of proteins after heating of calcium-fortified milks has been an ongoing problem in the dairy industry. This undesirable effect restricts the manufacture of calcium rich dairy products. To overcome this problem, a completely new approach in controlling the heat stability of dairy protein solutions, developed in our lab, has been employed. In this approach, high intensity, low frequency ultrasound is applied for a very short duration after a pre-heating step at ?70 °C. The ultrasound breaks apart whey/whey and whey/casein aggregates through the process of acoustic cavitation. Protein aggregates do not reform on subsequent post-heating, thereby making the systems heat stable. In this paper, the acid gelation properties of ultrasonicated calcium-enriched skim milks have also been investigated. It is shown that ultrasonication alone does not change the gelation properties significantly whereas a sequence of preheating (72 °C/1 min) followed by ultrasonication leads to decreased gelation times, decreased gel syneresis and increased skim milk viscosity in comparison to heating alone. Overall, ultrasonication has the potential to provide calcium-fortified dairy products with increased heat stability. However, enhanced gelation properties can only be achieved when ultrasonication is completed in conjunction with heating. PMID:24698480

Chandrapala, Jayani; Bui, Don; Kentish, Sandra; Ashokkumar, Muthupandian

2014-05-01

120

Once-yearly zoledronic acid in hip fracture prevention  

PubMed Central

Osteoporosis is an escalating global problem. Hip fractures, the most catastrophic complication of osteoporosis, continue to cause significant mortality and morbidity despite increasing availability of effective preventative agents. Among these agents, oral bisphosphonates have been the first choice for the treatment and prevention of osteoporotic fractures. However, the use of oral bisphosphonates, especially in the older population, has been limited by their side effects and method of administration thus compromising their persistent use. The resultant low adherence by patients has undermined their full potential and has been associated with an increase in the incidence of fragility fractures. Recently, annual intravenous zoledronic acid (ZOL) has been approved for osteoporosis. Randomized controlled trials have demonstrated ZOL to be safe, have good tolerability and produce significant effect on bone mass and microarchitecture. Adherence has also been shown to be better with ZOL. Furthermore two large trials firmly demonstrated significant anti-osteoporotic effect (?59% relative risk reduction of hip fractures) and mortality benefit (28% reduction in mortality) of ZOL in older persons with recent hip fractures. In this review, we report the current evidence on the use of ZOL for the prevention of hip fractures in the elderly. We also report the pharmacological characteristics and the advantages and disadvantages of ZOL in this particular group. PMID:19503777

Demontiero, Oddom; Duque, Gustavo

2009-01-01

121

Habit modification of calcium carbonate in the presence of malic acid  

SciTech Connect

The ability of malic acid to control calcium carbonate morphology has been investigated by aging calcium chloride solution in the presence of urea in a 90 deg. C bath. Malic acid favors the formation of calcite. A transition from single block to aggregate with special morphology occurs upon increasing malic acid concentration. The morphological development of CaCO{sub 3} crystal obviously depends on the starting pH. CaCO{sub 3} crystal grows from spindle seed to dumbbell in the pH regime from 7 to 11; while it evolves from spindle seed, through peanut, to sphere at pH=11.5. Both dumbbell and sphere consist of rods that are elongated along c-axis and capped with three smooth, well-defined rhombic {l_brace}1 0 4{r_brace} faces. A tentative growth mechanism is proposed based on the fractal model suggested by R. Kniep and S. Busch [Angew. Chem. Int. Ed. Engl. 35 (1996) 2624]. - Graphical abstract: Dumbbell-like CaCO{sub 3} particles obtained in the presence of malic acid.

Mao Zhaofeng [Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Huang Jianhua [Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018 (China)], E-mail: jhhuang@zstu.edu.cn

2007-02-15

122

Calcium-Rich Foods  

MedlinePLUS

... Disorders - Osteoporosis - Prevention - Calcium - Calcium content of common foods Printer friendly Email Share Tweet Like Below is ... Green/French beans 90 g cooked 50 Starchy foods Food Serving Size Calcium (mg) Pasta (cooked) 180 ...

123

Composite scaffolds of nano calcium deficient hydroxyapatite/multi-(amino acid) copolymer for bone tissue regeneration.  

PubMed

In this study, nano calcium deficient hydroxyapatite (n-DA)/multi-(amino acid) copolymer composite scaffolds were prepared by injection molding foaming method using calcium sulphate dihydrate as a foaming agent. The composite scaffolds showed well interconnected macropores with the pore size of ranging from 100 to 600 ?m, porosity of 81 % and compressive strength of 12 MPa, and the compressive strength obviously affected by the porosity. The composite scaffolds could be slowly degraded in phosphate buffered solution (PBS), which lost its initial weight of 61 w % after immersion into PBS for 12 weeks, and the porosity significantly affected the degradability of the scaffolds. Moreover, it was found that the composite scaffolds could promote the MG-63 cells growth and proliferation, and enhance its alkaline phosphatase activity. The implantation of the scaffolds into the femoral bone of rabbits confirmed that the composite scaffolds were biocompatibitive, degradable, and osteoconductive in vivo. PMID:24488438

Li, Hong; Yang, Lili; Dong, Xieping; Gu, Yifei; Lv, Guoyu; Yan, Yonggang

2014-05-01

124

Inhibiting Gastric Acid Production Does Not Affect Intestinal Calcium Absorption in Young, Healthy Individuals: A Randomized, Crossover, Controlled Clinical Trial  

PubMed Central

Proton pump inhibitors (PPIs) are the most potent gastric acid suppressing drugs available, and their use is widespread. An emerging concern about chronic PPI therapy is whether these drugs impair intestinal calcium absorption, resulting in a negative calcium balance and thereby potentially causing bone loss. The objective of this study was to evaluate the acute effect of the PPI esomeprazole or placebo on intestinal calcium absorption in healthy adults. Twelve young adults participated in a placebo-controlled, double-blind, crossover study. There were two 3-week interventions that included a 14-day adjustment period (designed to stabilize calcium homeostasis) followed by 6 days of a diet containing 800 mg of calcium and 2.1 g/kg of protein (intervention). During the last 3 days of the adjustment period and throughout the intervention period, subjects consumed esomeprazole or placebo. Half the subjects underwent 24-hour continuous gastric acid pH monitoring. Intestinal calcium absorption was measured using dual-stable calcium isotopes at the end of each intervention. Treatment with esomprazole significantly increased gastric pH (mean pH on PPI 5.38 ± 0.13, mean pH on placebo 2.70 ± 0.44, p =.005). Neither calcium absorption (PPI 34.2% ± 2.4%, placebo 31.5% ± 2.1%, p =.24) nor urinary calcium (PPI 321 ± 38 mg/34 hours, placebo 355 ± 37 mg/34 hours, p =.07) differed between the PPI and placebo groups. It is concluded that short-term gastric acid suppression by PPIs does not attenuate intestinal calcium absorption in healthy young adults. PMID:20499372

Wright, Matthew J; Sullivan, Rebecca R; Gaffney-Stomberg, Erin; Caseria, Donna M; O’Brien, Kimberly O; Proctor, Deborah D; Simpson, Christine A; Kerstetter, Jane E; Insogna, Karl L

2010-01-01

125

PREDICTING THE PERFORMANCE OF AN ELEVATED WATER TABLE FOR PREVENTING ACID  

E-print Network

PREDICTING THE PERFORMANCE OF AN ELEVATED WATER TABLE FOR PREVENTING ACID MINE DRAINAGE M. The effectiveness of an elevated water table in preventing acid mine drainage (AMD) can be quantified using diffusion de l'oxygène en milieu quasi saturé. Cette efficacité à empêcher le drainage minier acide (DMA

Aubertin, Michel

126

Antibiotic-loaded synthetic calcium sulfate beads for prevention of bacterial colonization and biofilm formation in periprosthetic infections.  

PubMed

Periprosthetic infection (PI) causes significant morbidity and mortality after fixation and joint arthroplasty and has been extensively linked to the formation of bacterial biofilms. Poly(methyl methacrylate) (PMMA), as a cement or as beads, is commonly used for antibiotic release to the site of infection but displays variable elution kinetics and also represents a potential nidus for infection, therefore requiring surgical removal once antibiotics have eluted. Absorbable cements have shown improved elution of a wider range of antibiotics and, crucially, complete biodegradation, but limited data exist as to their antimicrobial and antibiofilm efficacy. Synthetic calcium sulfate beads loaded with tobramycin, vancomycin, or vancomycin-tobramycin dual treatment (in a 1:0.24 [wt/wt] ratio) were assessed for their abilities to eradicate planktonic methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis relative to that of PMMA beads. The ability of the calcium sulfate beads to prevent biofilm formation over multiple days and to eradicate preformed biofilms was studied using a combination of viable cell counts, confocal microscopy, and scanning electron microscopy of the bead surface. Biofilm bacteria displayed a greater tolerance to the antibiotics than their planktonic counterparts. Antibiotic-loaded beads were able to kill planktonic cultures of 10(6) CFU/ml, prevent bacterial colonization, and significantly reduce biofilm formation over multiple days. However, established biofilms were harder to eradicate. These data further demonstrate the difficulty in clearing established biofilms; therefore, early preventive measures are key to reducing the risk of PI. Synthetic calcium sulfate loaded with antibiotics has the potential to reduce or eliminate biofilm formation on adjacent periprosthetic tissue and prosthesis material and, thus, to reduce the rates of periprosthetic infection. PMID:25313221

Howlin, R P; Brayford, M J; Webb, J S; Cooper, J J; Aiken, S S; Stoodley, P

2015-01-01

127

Dietary magnesium, not calcium, prevents vascular calcification in a mouse model for pseudoxanthoma elasticum  

PubMed Central

Pseudoxanthoma elasticum (PXE) is a heritable disorder characterized by ectopic calcification of connective tissue in skin, Bruch’s membrane of the eye, and walls of blood vessels. PXE is caused by mutations in the ABCC6 gene, but the exact etiology is still unknown. While observations on patients suggest that high calcium intake worsens the clinical symptoms, the patient organization PXE International has published the dietary advice to increase calcium intake in combination with increased magnesium intake. To obtain more data on this controversial issue, we examined the effect of dietary calcium and magnesium in the Abcc6?/? mouse, a PXE mouse model which mimics the clinical features of PXE. Abcc6?/? mice were placed on specific diets for 3, 7, and 12 months. Disease severity was measured by quantifying calcification of blood vessels in the kidney. Raising the calcium content in the diet from 0.5% to 2% did not change disease severity. In contrast, simultaneous increase of both calcium (from 0.5% to 2.0%) and magnesium (from 0.05% to 0.2%) slowed down the calcification significantly. Our present findings that increase in dietary magnesium reduces vascular calcification in a mouse model for PXE should stimulate further studies to establish a dietary intervention for PXE. PMID:20177653

Waarsing, Jan H.; de Wolf, Anneke; ten Brink, Jacoline B.; Loves, Willem J. P.; Bergen, Arthur A. B.

2010-01-01

128

Modification of fatty acid profile of cow milk by calcium salts of fatty acids and its use in ice cream.  

PubMed

This study was conducted to determine the effect of calcium salts of fatty acids (CSFA) on fatty acid profile of milk of "Sahiwal" cows and suitability of milk with modified fatty acids in the formulation of ice cream. Fatty acid profile of cow milk was modified by feeding CSFA to eighteen randomly stratified "Sahiwal" cows of first and early lactation divided into three groups. CSFA were offered at two different levels i.e. T1 (150 g per cow per day) T2 (300 g per cow per day) both treatments were compared with a control (T0) without any addition of calcium salts of fatty acids. Iso caloric and iso nitrogenous feeds were given to both experimental groups and control. Concentrations of short chain fatty acids in T0, T1 and T2 were 9.85?±?0.48a, 8.8?±?0.24b and 7.1?±?0.37c %, respectively and the concentrations of C18:1 and C18:2 increased (P?acids profile) in ice cream did not have any adverse effect on pH, acidity and compositional attributes of ice cream. Viscosity of T1 was 67.94?±?3.77a as compared to (T0) control 68.75?±?2.46a (CP). Firmness of experimental samples and control were almost similar (P?>?0.05) overall acceptability score of T2 was 7.1?±?0.28b out of 9 (total score) which was more than 78?±?2.92 %. It was concluded that CSFA may be successfully incorporated up to T2 level (300 g per cow per day) into the feed of "Sahiwal" cows to produce milk with higher content of unsaturated fatty acids and it may be used in the formulation of ice cream with acceptable sensory characteristics and increased health benefits. PMID:25694719

Nadeem, Muhammad; Abdullah, Muhammad; Hussain, Imtiaz; Inayat, Saima

2015-02-01

129

Application of acidic calcium sulfate and e-polylysine to pre-rigor beef rounds for reduction of pathogens  

Technology Transfer Automated Retrieval System (TEKTRAN)

Foodborne illness continues to be a serious public health problem and is a major concern for the United States food industry. This study evaluated the effectiveness of warm solutions of acidic calcium sulfate (ACS), lactic acid (LA), episolon-polylysine (EPL), ACS plus EPL, and sterile distilled wa...

130

Fasudil prevents calcium oxalate crystal deposit and renal fibrogenesis in glyoxylate-induced nephrolithic mice.  

PubMed

Nephrolithiasis is a common kidney disease and one of the major causes of chronic renal insufficiency. We develop and utilize a glyoxylate induced mouse model of kidney calcium oxalate crystal deposition for studying the pharmacological effects of fasudil, a Rho associated protein kinase (ROCK) specific inhibitor, on the kidney injury and fibrosis caused by calcium oxalate crystallization and deposition. Glyoxylate was administrated intraperitoneally to C57BL/6J mice for five consecutive days to establish a mouse model of kidney calcium oxalate crystal formation and deposition. The results showed that the protein expression levels of E-cad and Pan-ck were lower, and the protein expression levels of ?-SMA and Vim were higher, in the kidney tissue of the glyoxylate induced model mice compared with the control mice. The changes in protein expression were weakened when the animals were pretreated with fasudil before glyoxylate administration. Expression of ROCK, PAI-1, and p-Smad proteins in the kidney tissue increased in response to glyoxylate treatment, and the increase was eased when the animals were pretreated with fasudil. Expression of Smad2 and Smad3 in the kidney tissue remained unchanged after glyoxylate administration. Cell apoptosis and proliferation in the kidney cortex and medulla were enhanced in response to the glyoxylate induced calcium oxalate crystal formation and deposition, and fasudil pre-treatment was able to attenuate the enhancement. The results suggest that Fasudil reduces the glyoxylate induced kidney calcium crystal formation and deposition and slows down the kidney fibrogenesis caused by calcium crystal deposition. The possible mechanism may be related the regulatory effects on Rho/ROCK signal transduction and epithelial-mesenchymal transition (EMT). PMID:25697583

Hu, Haiyan; Chen, Wei; Ding, Jiarong; Jia, Meng; Yin, Jingjing; Guo, Zhiyong

2015-04-01

131

A laboratory study of the heterogeneous reaction of nitric acid on calcium carbonate particles  

Microsoft Academic Search

It has been postulated that the reaction of nitric acid with calcium carbonate, namely, CaCO3(s)+2HNO3(g)->Ca(NO3)2(s)+CO2(g)+H2O(g), plays an important role in the atmosphere. In this study, transmission FTIR spectroscopy, diffuse reflectance UV-visible spectroscopy, transmission electron microscopy and a Knudsen cell reactor coupled to a quadrupole mass spectrometer have been used to investigate the heterogeneous reactivity of HNO3 on CaCO3 at 295

A. L. Goodman; G. M. Underwood; V. H. Grassian

2000-01-01

132

Acid-induced release of curcumin from calcium containing nanotheranostic excipient.  

PubMed

Poor water solubility is believed one of the most critical problems of numerous promising pharmaceutical ingredients in their successful clinical utilization. Nanomedicine holds considerable promise to address this challenge, because it extends the therapeutic window of hydrophobic drugs through nanonization approach. Recently, the integration of diagnostic agents with smart therapeutic nanocarriers is also an emerging research arena to simultaneously visualize diseased tissues, achieve site specific drug release and track the impact of therapy. In this study, we have developed a biocompatible smart theranostic nanosystem which transports a highly promising hydrophobic drug (curcumin) in response to mildly acidic environment. As calcium is a main constituent of human body, hence we exploited the reversible calcium chelate formation tendency of divalent calcium to load and unload curcumin molecules. Moreover, an emerging T1 contrast agent is also tethered onto the surface of nanocarrier to realize MRI diagnosis application. In-vitro cell experiments revealed a significantly high chemotherapeutic efficiency of curcumin nanoformulation (IC50; 1.67 ?g/mL), whereas free curcumin was found ineffective at the corresponding concentration (IC50; 29.72 ?g/mL). MR imaging test also validated the performance of resulting system. Our strategy can be extended for the targeted delivery of other hydrophobic pharmaceutical ingredients. PMID:25025519

Wang, Aifei; Muhammad, Faheem; Qi, Wenxiu; Wang, Nan; Chen, Liang; Zhu, Guangshan

2014-08-27

133

Prevention of falls and fractures in old people by administration of calcium and vitamin d. randomized clinical trial  

PubMed Central

Background There are many studies that associate vitamin D serum levels in older persons with muscle strength, physical performance and risk of fractures and falls. However, current evidence is insufficient to make a general recommendation for administrating calcium and vitamin D to older persons. The objective of this study is to determine the effectiveness of calcium and vitamin D supplementation in improving musculoskeletal function and decreasing the number of falls in person aged over 65 years. Methods/Design Phase III, randomized, double blind, placebo-controlled trial to evaluate the efficacy of already marketed drugs in a new indication. It will be performed at Primary Care doctor visits at several Healthcare Centers in different Spanish Health Areas. A total of 704 non-institutionalized subjects aged 65 years or older will be studied (sample size calculated for a statistical power of 80%, alpha error 0.05, annual incidence of falls 30% and expected reduction of 30% to 20% and expected loss to follow up of 20%). The test drug containing 800 IU of vitamin D and 1000 mg of calcium will be administered daily. The control group will receive a placebo. The subjects will be followed up over two years. The primary variable will be the incidence of spontaneous falls. The secondary variables will include: consequences of the falls (fractures, need for hospitalization), change in calcidiol plasma levels and other analytical determinations (transaminases, PTH, calcium/phosphorous, albumin, creatinine, etc.), change in bone mass by densitometry, change in muscle strength in the dominant hand and change in musculoskeletal strength, risk factors for falls, treatment compliance, adverse effects and socio-demographic data. Discussion The following principles have been considered in the development of this Project: the product data are sufficient to ensure that the risks assumed by the study participants are acceptable, the study objectives will probably provide further knowledge on the problem studied and the available information justifies the performance of the study and its possible risk for the participants. If calcium and vitamin D supplementation is effective in the prevention of falls and fractures in the elderly population, a recommendation may be issued with the aim of preventing some of the consequences of falls that affect quality of life and the ensuing personal, health and social costs. Trial Registration ClinicalTrials.gov: NCT01452243 Clinical trial authorized by the Spanish Medicines Agency: EudraCT number 2006-001643-63. PMID:22151975

2011-01-01

134

Surface Acidity and Solid-State Compatibility of Excipients with an Acid-Sensitive API: Case Study of Atorvastatin Calcium.  

PubMed

The objectives of this study were to measure the apparent surface acidity of common excipients and to correlate the acidity with the chemical stability of an acid-sensitive active pharmaceutical ingredient (API) in binary API-excipient powder mixtures. The acidity of 26 solid excipients was determined by two methods, (i) by measuring the pH of their suspensions or solutions and (ii) the pH equivalent (pHeq) measured via ionization of probe molecules deposited on the surface of the excipients. The chemical stability of an API, atorvastatin calcium (AC), in mixtures with the excipients was evaluated by monitoring the appearance of an acid-induced degradant, atorvastatin lactone, under accelerated storage conditions. The extent of lactone formation in AC-excipient mixtures was presented as a function of either solution/suspension pH or pHeq. No lactone formation was observed in mixtures with excipients having pHeq > 6, while the lactone levels were pronounced (> 0.6% after 6 weeks at 50°C/20% RH) with excipients exhibiting pHeq < 3. The three pHeq regions (> 6, 3-6, and < 3) were consistent with the reported solution pH-stability profile of AC. In contrast to the pHeq scale, lactone formation did not show any clear trend when plotted as a function of the suspension/solution pH. Two mechanisms to explain the discrepancy between the suspension/solution pH and the chemical stability data were discussed. Acidic excipients, which are expected to be incompatible with an acid-sensitive API, were identified based on pHeq measurements. The incompatibility prediction was confirmed in the chemical stability tests using AC as an example of an acid-sensitive API. PMID:25319055

Govindarajan, Ramprakash; Landis, Margaret; Hancock, Bruno; Gatlin, Larry A; Suryanarayanan, Raj; Shalaev, Evgenyi Y

2015-04-01

135

Calcium carbonate breath test for non-invasive estimation of gastric acid secretion.  

PubMed

Gastric acid measurement is useful in assessing the effectiveness of antisecretory drugs, however, the conventional tests involve invasive nasogastric intubation. Orally administered ¹³C-labeled calcium carbonate (Ca¹³CO?) reacts with gastric acid to produce ¹³C-labeled carbon dioxide (¹³CO?), which is then excreted in the breath. The objective of this study was to evaluate the suitability of Ca¹³CO3 breath test for estimating gastric acid secretion in human noninvasively. First, the Ca¹³CO? breath test and the measurement of pooled gastric acid under a fasting condition were performed in 6 healthy volunteers to evaluate the correlation between the two parameters. Next, endoscopic gastric acid collection and the Ca¹³CO? breath test were performed on different days after pentagastrin injection in 20 subjects to evaluate the correlation between the tests and the reproducibility. Finally, the same studies were repeated in 4 subjects before and after 1-week rabeprazole, a proton pump inhibitor, administration. The maximum CO? concentration (Cmax) correlated very well with the amount of pooled gastric acid (r = 0.95), suggesting that Ca¹³CO? breath test values well reflected the fasting intragastric acidity. The ¹³CO? concentration after pentagastrin injection correlated well with pentagastrin-stimulated maximal acid output (r = 0.79 at 20 min). The reproducibility of the Ca¹³CO? breath test under pentagastrin-stimulation was good (coefficient of variation = 0.11). Rabeprazole administration markedly reduced the values of the Ca¹³CO? breath test, suggesting that it can sensitively assess the efficacy of rabeprazole. The Ca¹³CO? breath test can potentially be a useful method for non-invasive estimation for gastric acid secretion in human. PMID:24670370

Shinkai, Hirohiko; Iijima, Katsunori; Koike, Tomoyuki; Nakagawa, Kenichiro; Maejima, Ryuhei; Endo, Hiroyuki; Ara, Nobuyuki; Asano, Naoki; Imatani, Akira; Ohara, Shuichi; Shimosegawa, Tooru

2014-01-01

136

Biosynthesis of L-ascorbic acid and conversion of carbons 1 and 2 of L-ascorbic acid to oxalic acid occurs within individual calcium oxalate crystal idioblasts.  

PubMed

L-Ascorbic acid (AsA) and its metabolic precursors give rise to oxalic acid (OxA) found in calcium oxalate crystals in specialized crystal idioblast cells in plants; however, it is not known if AsA and OxA are synthesized within the crystal idioblast cell or transported in from surrounding mesophyll cells. Isolated developing crystal idioblasts from Pistia stratiotes were used to study the pathway of OxA biosynthesis and to determine if idioblasts contain the entire path and are essentially independent in OxA synthesis. Idioblasts were supplied with various (14)C-labeled compounds and examined by micro-autoradiography for incorporation of (14)C into calcium oxalate crystals. [(14)C]OxA gave heavy labeling of crystals, indicating the isolated idioblasts are functional in crystal formation. Incubation with [1-(14)C]AsA also gave heavy labeling of crystals, whereas [6-(14)C]AsA gave no labeling. Labeled precursors of AsA (L-[1-(14)C]galactose; D-[1-(14)C]mannose) also resulted in crystal labeling, as did the ascorbic acid analog, D-[1-(14)C]erythorbic acid. Intensity of labeling of isolated idioblasts followed the pattern OxA > AsA (erythorbic acid) > L-galactose > D-mannose. Our results demonstrate that P. stratiotes crystal idioblasts synthesize the OxA used for crystal formation, the OxA is derived from the number 1 and 2 carbons of AsA, and the proposed pathway of ascorbic acid synthesis via D-mannose and L-galactose is operational in individual P. stratiotes crystal idioblasts. These results are discussed with respect to fine control of calcium oxalate precipitation and the concept of crystal idioblasts as independent physiological compartments. PMID:11161021

Kostman, T A; Tarlyn, N M; Loewus, F A; Franceschi, V R

2001-02-01

137

Dissolution mechanism of calcium apatites in acids: A review of literature  

PubMed Central

Eight dissolution models of calcium apatites (both fluorapatite and hydroxyapatite) in acids were drawn from the published literature, analyzed and discussed. Major limitations and drawbacks of the models were conversed in details. The models were shown to deal with different aspects of apatite dissolution phenomenon and none of them was able to describe the dissolution process in general. Therefore, an attempt to combine the findings obtained by different researchers was performed which resulted in creation of the general description of apatite dissolution in acids. For this purpose, eight dissolution models were assumed to complement each other and provide the correct description of the specific aspects of apatite dissolution. The general description considers all possible dissolution stages involved and points out to some missing and unclear phenomena to be experimentally studied and verified in future. This creates a new methodological approach to investigate reaction mechanisms based on sets of affine data, obtained by various research groups under dissimilar experimental conditions. PMID:25237611

Dorozhkin, Sergey V

2012-01-01

138

Dissolution mechanism of calcium apatites in acids: A review of literature.  

PubMed

Eight dissolution models of calcium apatites (both fluorapatite and hydroxyapatite) in acids were drawn from the published literature, analyzed and discussed. Major limitations and drawbacks of the models were conversed in details. The models were shown to deal with different aspects of apatite dissolution phenomenon and none of them was able to describe the dissolution process in general. Therefore, an attempt to combine the findings obtained by different researchers was performed which resulted in creation of the general description of apatite dissolution in acids. For this purpose, eight dissolution models were assumed to complement each other and provide the correct description of the specific aspects of apatite dissolution. The general description considers all possible dissolution stages involved and points out to some missing and unclear phenomena to be experimentally studied and verified in future. This creates a new methodological approach to investigate reaction mechanisms based on sets of affine data, obtained by various research groups under dissimilar experimental conditions. PMID:25237611

Dorozhkin, Sergey V

2012-02-26

139

Formation of calcium carbonate films on chitosan substrates in the presence of polyacrylic acid  

SciTech Connect

In this investigation, chitosan membranes with different surface average degrees of deacetylation (DA) are prepared and then are employed as the support matrix to culture calcium carbonate (CaCO{sub 3}). In the presence of high concentration of polyacrylic acid (PAA), the CaCO{sub 3} films obtained on the surface of all chitosan films mainly consisted of vaterite, which suggests the presence of bulk PAA plays an overwhelming part in stabilizing the vaterite. As a comparison, the influences of active groups indicate that only in case of low concentration PAA the thin CaCO{sub 3} films grown on chitosan with 8% DA mainly consisted of vaterite owing to the strong nucleation ability of -NH{sub 2} group, whereas, for those grown on chitosan with 80% DA the CaCO{sub 3} films mainly consisted of aragonite. A more complex scenario revealed that in the case of intermediate concentration of PAA the formed polymorphs behave as mixtures of vaterite and aragonite. - Graphical abstract: Chitosan membranes with different degrees of deacetylation (DA) are employed as support to culture calcium carbonate (CaCO{sub 3}). In high concentration of polyacrylic acid (PAA), the CaCO{sub 3} films obtained consisted of vaterite. However, the CaCO{sub 3} film grown on chitosan with 8% DA mainly consisted of vaterite as opposed to aragonite for chitosan with 8% DA. The schematic presentation of the formation of calcium carbonate on chitosan films with different degrees of acetylation in the presence of PAA with low-, mid- and high concentrations.

He, Linghao; Xue, Rui [Zhengzhou University of Light Industry Henan Provincial Key Laboratory of Surface and Interface Science, Henan, Zhengzhou 450002 (China); Song, Rui, E-mail: rsong@gucas.ac.c [Zhengzhou University of Light Industry Henan Provincial Key Laboratory of Surface and Interface Science, Henan, Zhengzhou 450002 (China); College of Chemistry and Chemical Engineering, Graduate University of Chinese Academy of Sciences, Beijing 100049 (China)

2009-05-15

140

Calcium and bone disease  

PubMed Central

Calcium transport and calcium signaling are of basic importance in bone cells. Bone is the major store of calcium and a key regulatory organ for calcium homeostasis. Bone, in major part, responds to calcium-dependent signals from the parathyroids and via vitamin D metabolites, although bone retains direct response to extracellular calcium if parathyroid regulation is lost. Improved understanding of calcium transporters and calcium-regulated cellular processes has resulted from analysis of genetic defects, including several defects with low or high bone mass. Osteoblasts deposit calcium by mechanisms including phosphate and calcium transport with alkalinization to absorb acid created by mineral deposition; cartilage calcium mineralization occurs by passive diffusion and phosphate production. Calcium mobilization by osteoclasts is mediated by acid secretion. Both bone forming and bone resorbing cells use calcium signals as regulators of differentiation and activity. This has been studied in more detail in osteoclasts, where both osteoclast differentiation and motility are regulated by calcium. PMID:21674636

Blair, Harry C.; Robinson, Lisa J.; Huang, Christopher L.-H.; Sun, Li; Friedman, Peter A.; Schlesinger, Paul H.; Zaidi, Mone

2013-01-01

141

Supplementing a low-protein diet with dibasic amino acids increases urinary calcium excretion in young women.  

PubMed

Increasing dietary protein within a physiologic range stimulates intestinal calcium absorption, but it is not known if specific amino acids or dietary protein as a whole are responsible for this effect. Therefore, we selectively supplemented a low-protein (0.7 g/kg) diet with either the calcium-sensing receptor-activating amino acids (CaSR-AAAs) L-tryptophan, L-phenylalanine, and L-histidine, or the dibasic amino acids (DAAs) L-arginine and L-lysine, to achieve intakes comparable to the content of a high-protein diet (2.1 g/kg) and measured intestinal calcium absorption. Fourteen young women took part in a placebo-controlled, double-blind, crossover feeding trial in which each participant ingested a 6-d low-protein diet supplemented with CaSR-AAAs, DAAs, or methylcellulose capsules (control) after an 11-d adjustment period. All participants ingested all 3 diets in random order. Intestinal calcium absorption was measured between days 5 and 6 using dual-stable calcium isotopes ((42)Ca, (43)Ca, and (44)Ca). There was no difference in calcium absorption between the diet supplemented with CaSR-AAAs (22.9 ± 2.0%) and the control diet (22.3 ± 1.4%) (P = 0.64). However, calcium absorption tended to be greater during the DAA supplementation period (25.2 ± 1.4%) compared with the control diet period (22.3 ± 1.4%) (P < 0.10). Larger and longer clinical trials are needed to clarify the possible benefit of arginine and lysine on calcium absorption. PMID:24431325

Bihuniak, Jessica D; Sullivan, Rebecca R; Simpson, Christine A; Caseria, Donna M; Huedo-Medina, Tania B; O'Brien, Kimberly O; Kerstetter, Jane E; Insogna, Karl L

2014-03-01

142

Supplementing a Low-Protein Diet with Dibasic Amino Acids Increases Urinary Calcium Excretion in Young Women12  

PubMed Central

Increasing dietary protein within a physiologic range stimulates intestinal calcium absorption, but it is not known if specific amino acids or dietary protein as a whole are responsible for this effect. Therefore, we selectively supplemented a low-protein (0.7 g/kg) diet with either the calcium-sensing receptor-activating amino acids (CaSR-AAAs) L-tryptophan, L-phenylalanine, and L-histidine, or the dibasic amino acids (DAAs) L-arginine and L-lysine, to achieve intakes comparable to the content of a high-protein diet (2.1 g/kg) and measured intestinal calcium absorption. Fourteen young women took part in a placebo-controlled, double-blind, crossover feeding trial in which each participant ingested a 6-d low-protein diet supplemented with CaSR-AAAs, DAAs, or methylcellulose capsules (control) after an 11-d adjustment period. All participants ingested all 3 diets in random order. Intestinal calcium absorption was measured between days 5 and 6 using dual-stable calcium isotopes (42Ca, 43Ca, and 44Ca). There was no difference in calcium absorption between the diet supplemented with CaSR-AAAs (22.9 ± 2.0%) and the control diet (22.3 ± 1.4%) (P = 0.64). However, calcium absorption tended to be greater during the DAA supplementation period (25.2 ± 1.4%) compared with the control diet period (22.3 ± 1.4%) (P < 0.10). Larger and longer clinical trials are needed to clarify the possible benefit of arginine and lysine on calcium absorption. PMID:24431325

Bihuniak, Jessica D.; Sullivan, Rebecca R.; Simpson, Christine A.; Caseria, Donna M.; Huedo-Medina, Tania B.; O’Brien, Kimberly O.; Kerstetter, Jane E.; Insogna, Karl L.

2014-01-01

143

Dietary magnesium, not calcium, prevents vascular calcification in a mouse model for pseudoxanthoma elasticum  

Microsoft Academic Search

Pseudoxanthoma elasticum (PXE) is a heritable disorder characterized by ectopic calcification of connective tissue in skin,\\u000a Bruch’s membrane of the eye, and walls of blood vessels. PXE is caused by mutations in the ABCC6 gene, but the exact etiology is still unknown. While observations on patients suggest that high calcium intake worsens the\\u000a clinical symptoms, the patient organization PXE International

Theo G. M. F. Gorgels; Jan H. Waarsing; Anneke de Wolf; Jacoline B. ten Brink; Willem J. P. Loves; Arthur A. B. Bergen

2010-01-01

144

Sigma-1 receptor activation prevents intracellular calcium dysregulation in cortical neurons during in vitro ischemia.  

PubMed

Sigma receptors are putative targets for neuroprotection following ischemia; however, little is known on their mechanism of action. One of the key components in the demise of neurons following ischemic injury is the disruption of intracellular calcium homeostasis. Fluorometric calcium imaging was used to examine the effects of sigma receptor activation on changes in intracellular calcium concentrations ([Ca(2+)](i)) evoked by in vitro ischemia in cultured cortical neurons from embryonic rats. The sigma receptor agonist, 1,3-di-o-tolyl-guanidine (DTG), was shown to depress [Ca(2+)](i) elevations observed in response to ischemia induced by sodium azide and glucose deprivation. Two sigma receptor antagonists, metaphit [1-(1-(3-isothiocyanatophenyl)-cyclohexyl)-piperidine] and BD-1047 (N-[2-3,4-dichlorophenyl)-ethyl]-N-methyl-2-(dimethylamino)ethylamine), were shown to blunt the ability of DTG to inhibit ischemia-evoked increases in [Ca(2+)](i), revealing that the effects are mediated by activation of sigma receptors and not via the actions of DTG on nonspecific targets such as N-methyl-d-aspartate receptors. DTG inhibition of ischemia-induced increases in [Ca(2+)](i) was mimicked by the sigma-1 receptor-selective agonists, carbetapentane, (+)-pentazocine and PRE-084 [2-(4-morpholinethyl) 1-phenylcyclohexanecarboxylate hydrochloride], but not by the sigma-2-selective agonist, ibogaine, showing that activation of sigma-1 receptors is responsible for the effects. In contrast, DTG, carbetapentane, and ibogaine blocked spontaneous, synchronous calcium transients observed in our preparation at concentrations consistent with sigma receptor-mediated effects, indicating that both sigma-1 and sigma-2 receptors regulate events that affect [Ca(2+)](i) in cortical neurons. Our studies show that activation of sigma receptors can ameliorate [Ca(2+)](i) dysregulation associated with ischemia in cortical neurons and, thus, identify one of the mechanisms by which these receptors may exert their neuroprotective properties. PMID:16988055

Katnik, Christopher; Guerrero, Waldo R; Pennypacker, Keith R; Herrera, Yelenis; Cuevas, Javier

2006-12-01

145

EFFECTS OF COMBINED POTASSIUM ALKALI AND CALCIUM SUPPLEMENTATION ON THE PREVENTION OF BONE LOSS IN POSTMENOPAUSAL WOMEN  

Technology Transfer Automated Retrieval System (TEKTRAN)

Potassium citrate improves calcium balance by conferring an alkali load. Calcium supplementation slows postmenopausal bone loss by inhibiting parathyroid hormone (PTH) secretion. We explored whether combined treatment (Combination) with potassium citrate (KCitrate) and calcium citrate (CaCitrate) is...

146

Purification and characterisation of a glutamic acid-containing peptide with calcium-binding capacity from whey protein hydrolysate.  

PubMed

The bioavailability of dietary ionised calcium is affected by intestinal basic environment. Calcium-binding peptides can form complexes with calcium to improve its absorption and bioavailability. The aim of this study was focused on isolation and characterisation of a calcium-binding peptide from whey protein hydrolysates. Whey protein was hydrolysed using Flavourzyme and Protamex with substrate to enzyme ratio of 25:1 (w/w) at 49 °C for 7 h. The calcium-binding peptide was isolated by DEAE anion-exchange chromatography, Sephadex G-25 gel filtration and reversed phase high-performance liquid chromatography (RP-HPLC). A purified peptide of molecular mass 204 Da with strong calcium binding ability was identified on chromatography/electrospray ionisation (LC/ESI) tandem mass spectrum to be Glu-Gly (EG) after analysis and alignment in database. The calcium binding capacity of EG reached 67·81 ?g/mg, and the amount increased by 95% compared with whey protein hydrolysate complex. The UV and infrared spectrometer analysis demonstrated that the principal sites of calcium-binding corresponded to the carboxyl groups and carbonyl groups of glutamic acid. In addition, the amino group and peptide amino are also the related groups in the interaction between EG and calcium ion. Meanwhile, the sequestered calcium percentage experiment has proved that EG-Ca is significantly more stable than CaCl2 in human gastrointestinal tract in vitro. The findings suggest that the purified dipeptide has the potential to be used as ion-binding ingredient in dietary supplements. PMID:25592629

Huang, Shun-Li; Zhao, Li-Na; Cai, Xixi; Wang, Shao-Yun; Huang, Yi-Fan; Hong, Jing; Rao, Ping-Fan

2015-02-01

147

Linoleic acid increases adhesion, chemotaxis, granule release, intracellular calcium mobilisation, MAPK phosphorylation and gene expression in bovine neutrophils.  

PubMed

Neutrophils are critical to the innate immune response; therefore, the proper function of neutrophils is critical to avoid the development of certain diseases. Linoleic acid, a polyunsaturated long-chain fatty acid, is one of the most abundant long-chain fatty acids found in the plasma of cows after giving birth. In this study, we evaluated the effects of linoleic acid treatment on bovine neutrophil adhesion, chemotaxis, metalloproteinase (MMP)-9 release, CD11b expression, intracellular calcium mobilisation, mitogen-activating protein kinase (MAPK) phosphorylation and COX-2 and IL-8 expression. Bovine neutrophils isolated from healthy heifers were incubated with different concentrations of linoleic acid, and then neutrophil responses were evaluated. Our results show that the treatment of neutrophils with 100 ?M linoleic acid increased their adhesion to the bovine endothelial cell line CPA47. The results of a transwell migration assay revealed that linoleic acid could also promote the chemotaxis of bovine neutrophils. Furthermore, linoleic acid treatment increased MMP-9 activity and CD11b cell surface expression in neutrophils. Fifty and 100 ?M linoleic acid also increased intracellular calcium mobilisation in neutrophils loaded with Fluo-4 AM dye. Linoleic acid also rapidly (2-5 min) stimulated the phosphorylation of ERK1/2 and p38 MAPK as evaluated by immunoblot. Finally, COX-2 and IL-8 mRNA expression increased after 2h of linoleic acid treatment. In conclusion, linoleic acid stimulates adhesion, chemotaxis, granule release and intracellular responses in bovine neutrophils. PMID:23267746

Mena, Jaqueline; Manosalva, Carolina; Ramirez, Ruben; Chandia, Lhia; Carroza, Daniel; Loaiza, Anitsi; Burgos, Rafael A; Hidalgo, Maria A

2013-02-15

148

A comparison of calcium to zoledronic acid for improvement of cortical bone in an animal model of CKD  

PubMed Central

Patients with chronic kidney disease (CKD) have increased risk of fractures, yet the optimal treatment is unknown. In secondary analyses of large randomized trials, bisphosphonates have been shown to improve bone mineral density and reduce fractures. However, bisphosphonates are currently not recommended in patients with advanced kidney disease due to concern about over-suppressing bone remodeling, which may increase the risk of developing arterial calcification. In the present study we used a naturally occurring rat model of CKD with secondary hyperparathyroidism, the Cy/+ rat, and compared the efficacy of treatment with zoledronic acid, calcium given in water to simulate a phosphate binder, and the combination of calcium and zoledronic acid. Animals were treated beginning at 25 weeks of age (approximately 30% of normal renal function) and followed for ten weeks. The results demonstrate that both zoledronic acid and calcium improved bone volume by microCT and both equally suppressed mineral apposition rate, bone formation rate, and mineralizing surface of trabecular bone. In contrast, only calcium treatment with or without zoledronic acid improved cortical porosity and cortical biomechanical properties (ultimate load and stiffness) and lowered parathyroid hormone (PTH). However, only calcium treatment led to the adverse effects of increased arterial calcification and fibroblast growth factor 23 (FGF23). These results suggest zoledronic acid may improve trabecular bone volume in CKD in the presence of secondary hyperparathyroidism, but does not benefit extraskeletal calcification or cortical biomechanical properties. Calcium effectively reduces PTH and benefits both cortical and trabecular bone yet increases the degree of extra skeletal calcification. PMID:24038306

Moe, Sharon M.; Chen, Neal X.; Newman, Christopher L.; Gattone, Vincent H.; Organ, Jason M.; Chen, Xianming; Allen, Matthew R.

2013-01-01

149

[Regulation function of calcium on photosynthesis of Dimocarpus longana Lour. cv. wulongling under simulated acid rain stress].  

PubMed

Studies on the regulation function of calcium on photosynthesis of Dimocarpus longana under simulated acid rain stress showed that the photoreduction activity of chloroplasts was activated when the concentration of calcium ion in reaction medium ranged from 0 to 5 mmol.L-1, and peaked at the 3.5 mmol.L-1, which was 41.90% higher than that of control. Conversely, the activity of chloroplasts reduced 26.06% in the reaction medium with a concentration of 2 mmol.L-1 EGTA, as compared with the control. Both Mn2+ and Mg2+ could inhibit photoreduction activity. The photophosphorylation activity increased when the concentration of calcium ion in reaction medium ranged from 0 to 6 mmol.L-1, and peaked at the 4.5 mmol.L-1, while superoxidase dismutase (SOD) activity rose from 0 to 6 mmol.L-1 and peaked at 6 mmol.L-1. Calcium ion with the concentration of both 10 mmol.L-1 and 15 mmol.L-1 could increase the content of chlorophyll(Chl), stabilize the membrane structure of leaf discs, and reduce the membrane permeability under simulated acid rain with pH value of 3.0. The effect in 15 mmol.L-1 were better than in 10 mmol.L-1. However, the injury of acid rain to leaves was strengthened when the concentration of calcium was higher than 20 mmol.L-1. Net photosynthesis rate (Pn) rose when leaves sprayed with 15 mmol.L-1 Ca(NO3)2 before treatment of acid rain stress of pH 2.5. All of the results represented the excellent protection function of calcium on D. longana leaves under simulated acid rain. PMID:12561164

Qiu, Dongliang; Liu, Xinghui; Guo, Suzhi

2002-09-01

150

Influence of Calcium Addition on Growth of Highly Purified Syntrophic Cultures Degrading Long-Chain Fatty Acids  

PubMed Central

Two highly purified syntrophic associations resulting in acetogenesis from stearate (SM) and oleate (OM) were obtained from the sludges of a sewage digestor. In both cases, Methanospirillum hungatei together with short, motile, gram-negative, nonfluorescent rods morphologically similar to Syntrophomonas wolfei were identified by microscopic examination. Besides growing on volatile fatty acids (butyrate through caproate), both cultures grew on oleate (C18:1) and numerous even-numbered, saturated long-chain fatty acids (LCFA [decanoate through stearate]). In addition, during growth on LCFA, supplementation of the culture media with calcium chloride was an absolute requirement. The sole difference between the associations was observed when SM and OM cultures were transferred from a stearate to an oleate medium. The SM culture needed 10 days before starting to degrade oleate, whereas the OM culture grew immediately, but the OM culture also grew immediately when transferred to stearate medium. Saturated LCFA degradation occurred in the presence of equinormal amounts of calcium (fatty acid/Ca ratio, 2). On the other hand, OM degradation only took place in the presence of an equimolar amount of calcium (fatty acid/Ca ratio, 1). These observations are discussed by considering the solubility constants of LCFA as calcium salts and the toxicity of the free acids against microorganisms. PMID:16346761

Roy, Francis; Albagnac, Guy; Samain, Eric

1985-01-01

151

Influence of calcium addition on growth of highly purified syntrophic cultures degrading long-chain Fatty acids.  

PubMed

Two highly purified syntrophic associations resulting in acetogenesis from stearate (SM) and oleate (OM) were obtained from the sludges of a sewage digestor. In both cases, Methanospirillum hungatei together with short, motile, gram-negative, nonfluorescent rods morphologically similar to Syntrophomonas wolfei were identified by microscopic examination. Besides growing on volatile fatty acids (butyrate through caproate), both cultures grew on oleate (C(18:1)) and numerous even-numbered, saturated long-chain fatty acids (LCFA [decanoate through stearate]). In addition, during growth on LCFA, supplementation of the culture media with calcium chloride was an absolute requirement. The sole difference between the associations was observed when SM and OM cultures were transferred from a stearate to an oleate medium. The SM culture needed 10 days before starting to degrade oleate, whereas the OM culture grew immediately, but the OM culture also grew immediately when transferred to stearate medium. Saturated LCFA degradation occurred in the presence of equinormal amounts of calcium (fatty acid/Ca ratio, 2). On the other hand, OM degradation only took place in the presence of an equimolar amount of calcium (fatty acid/Ca ratio, 1). These observations are discussed by considering the solubility constants of LCFA as calcium salts and the toxicity of the free acids against microorganisms. PMID:16346761

Roy, F; Albagnac, G; Samain, E

1985-03-01

152

Preventive effect of a high fluoride toothpaste and arginine-carbonate toothpaste on dentinal tubules exposure followed by acid challenge: a dentine permeability evaluation  

PubMed Central

Background Considering the current high use of high fluoride toothpastes, the aim of the study was to quantify alterations in the root dentine permeability submitted to treatment with a high fluoride toothpaste and 8% arginine, calcium carbonate, sodium monofluorophosphate toothpaste as a preventive treatment for dentinal tubules exposure followed by acid challenge. Methods Thirty-third molars were sectioned below the cementoenamel. The root segments were connected to a hydraulic pressure apparatus to measure dentine permeability after the following sequential steps (n = 10 per group): I) Baseline; II) treatment with phosphoric acid for 30 s (maximum permeability); III) Toothbrushing (1 min) according to the experimental groups (G1- control; G2- 5000 ppm fluoride toothpaste; G3- 8% arginine-calcium carbonate toothpaste); IV) acid challenge for 5 min (orange juice). The data were converted into percentage, considering stage II as 100%. Results The results have shown a statistically significant decreasing on dentine permeability after treatment with toothpaste (Friedman test and Dunn’s post hoc test). Comparison among groups demonstrated a high increasing on dentine permeability when acid challenge was performed after toothbrushing with distilled water (control group) (Kruskal-Wallis and Dunn’s post hoc test). Conclusion The toothpaste treatment may provide sufficient resistance on dentine surface, preventing dentinal tubules exposure after acid challenge. PMID:24958423

2014-01-01

153

Calcium and humic acid affect seed germination, growth, and nutrient content of tomato (Lycopersicon esculentum L.) seedlings under saline soil conditions  

Microsoft Academic Search

The effects of calcium and humic acid on seed germination, growth and macro- and micro-nutrient contents of tomato (Lycopersicon esculentum L.) seedlings in saline soil conditions were evaluated. Different levels of humic acid (0, 500, 1000 and 2000 mg kg) and calcium (0, 100, 200 and 400 mg kg) were applied to growth media treated with 50 mg NaCl kg

Önder Türkmen; Atilla Dursun; Metin Turan; Çeknas Erdinç

2004-01-01

154

21 CFR 184.1199 - Calcium gluconate.  

Code of Federal Regulations, 2011 CFR

...1199 Calcium gluconate. (a) Calcium gluconate ([CH2 OH(CHOH...Reg. No. 299-28-5) is the calcium salt of gluconic acid which may...neutralization of gluconic acid with lime or calcium carbonate. (b) The...

2011-04-01

155

21 CFR 184.1199 - Calcium gluconate.  

Code of Federal Regulations, 2012 CFR

...1199 Calcium gluconate. (a) Calcium gluconate ([CH2 OH(CHOH...Reg. No. 299-28-5) is the calcium salt of gluconic acid which may...neutralization of gluconic acid with lime or calcium carbonate. (b) The...

2012-04-01

156

Blockage of mitochondrial calcium uniporter prevents iron accumulation in a model of experimental subarachnoid hemorrhage.  

PubMed

Previous studies have shown that iron accumulation is involved in the pathogenesis of brain injury following subarachnoid hemorrhage (SAH) and chelation of iron reduced mortality and oxidative DNA damage. We previously reported that blockage of mitochondrial calcium uniporter (MCU) provided benefit in the early brain injury after experimental SAH. This study was undertaken to identify whether blockage of MCU could ameliorate iron accumulation-associated brain injury following SAH. Therefore, we used two reagents ruthenium red (RR) and spermine (Sper) to inhibit MCU. Sprague-Dawley (SD) rats were randomly divided into four groups including sham, SAH, SAH+RR, and SAH+Sper. Biochemical analysis and histological assays were performed. The results confirmed the iron accumulation in temporal lobe after SAH. Interestingly, blockage of MCU dramatically reduced the iron accumulation in this area. The mechanism was revealed that inhibition of MCU reversed the down-regulation of iron regulatory protein (IRP) 1/2 and increase of ferritin. Iron-sulfur cluster dependent-aconitase activity was partially conserved when MCU was blocked. In consistence with this and previous report, ROS levels were notably reduced and ATP supply was rescued; levels of cleaved caspase-3 dropped; and integrity of neurons in temporal lobe was protected. Taken together, our results indicated that blockage of MCU could alleviate iron accumulation and the associated injury following SAH. These findings suggest that the alteration of calcium and iron homeostasis be coupled and MCU be considered to be a therapeutic target for patients suffering from SAH. PMID:25529443

Yan, Huiying; Hao, Shuangying; Sun, Xiaoyan; Zhang, Dingding; Gao, Xin; Yu, Zhuang; Li, Kuanyu; Hang, Chun-Hua

2015-01-24

157

Poly(?-glutamic acid)/silica hybrids with calcium incorporated in the silica network by use of a calcium alkoxide precursor.  

PubMed

Current materials used for bone regeneration are usually bioactive ceramics or glasses. Although they bond to bone, they are brittle. There is a need for new materials that can combine bioactivity with toughness and controlled biodegradation. Sol-gel hybrids have the potential to do this through their nanoscale interpenetrating networks (IPN) of inorganic and organic components. Poly(?-glutamic acid) (?-PGA) was introduced into the sol-gel process to produce a hybrid of ?-PGA and bioactive silica. Calcium is an important element for bone regeneration but calcium sources that are used traditionally in the sol-gel process, such as Ca salts, do not allow Ca incorporation into the silicate network during low-temperature processing. The hypothesis for this study was that using calcium methoxyethoxide (CME) as the Ca source would allow Ca incorporation into the silicate component of the hybrid at room temperature. The produced hybrids would have improved mechanical properties and controlled degradation compared with hybrids of calcium chloride (CaCl2 ), in which the Ca is not incorporated into the silicate network. Class II hybrids, with covalent bonds between the inorganic and organic species, were synthesised by using organosilane. Calcium incorporation in both the organic and inorganic IPNs of the hybrid was improved when CME was used. This was clearly observed by using FTIR and solid-state NMR spectroscopy, which showed ionic cross-linking of ?-PGA by Ca and a lower degree of condensation of the Si species compared with the hybrids made with CaCl2 as the Ca source. The ionic cross-linking of ?-PGA by Ca resulted in excellent compressive strength and reduced elastic modulus as measured by compressive testing and nanoindentation, respectively. All hybrids showed bioactivity as hydroxyapatite (HA) was formed after immersion in simulated body fluid (SBF). PMID:24838668

Poologasundarampillai, Gowsihan; Yu, Bobo; Tsigkou, Olga; Wang, Daming; Romer, Frederik; Bhakhri, Vineet; Giuliani, Finn; Stevens, Molly M; McPhail, David S; Smith, Mark E; Hanna, John V; Jones, Julian R

2014-06-23

158

Final Report On the Safety Assessment of Glycolic Acid, Ammonium, Calcium, Potassium, and Sodium Glycolates, Methyl, Ethyl, Propyl, and Butyl Glycolates, and Lactic Acid, Ammonium, Calcium, Potassium, Sodium, and Tea-Lactates, Methyl, Ethyl, Isopropyl, and Butyl Lactates, and Lauryl, Myristyl, and Cetyl Lactates  

Microsoft Academic Search

This report provides a review of the safety of Glycolic Acid, Ammonium, Calcium, Potassium, and Sodium Glycolates, Methyl, Ethyl, Propyl, and Butyl Glycolates, Lactic Acid, Ammonium, Calcium, Potassium, Sodium, and TEA-Lactates, and Lauryl, Myristyl, and Cetyl Lactates. These ingredients belong to a group known as alpha-hydroxy acids (AHAs). Products containing these ingredients may be for consumer use, salon use, or

F. A. Andersen

1998-01-01

159

Design of chiral LC separations for calcium antagonists on alpha 1-acid glycoprotein and ovomucoid columns.  

PubMed

Three chiral calcium antagonist drugs, gallopamil and two dihydropyridine derivatives, have been successfully separated within short retention times using both the alpha 1-acid glycoprotein chiral stationary phase (Chiral-AGP) and the ovomucoid column (Ultron ES-OVM). Aqueous buffer at defined pH is modified by the addition of an organic component, in order to modulate the retention properties of each system. Optimization of pH and organic modifier is carried out using the modified simplex method, with Kaiser's peak separation function as a criterion. The influence of pH and percentage of organic modifier on retention, selectivity, resolution and column performance are discussed for the two dihydropyridines analysed on Chiral-AGP and Ultron ES-OVM stationary phases. A new method is proposed as a new chiral system suitability test for these protein-based phases, utilizing a racemic mixture of closely eluting verapamil enantiomers as a probe. PMID:1298397

De Lorenzi, E; Fell, A F; Caccialanza, G; Massolini, G; Kitsos, M

1992-01-01

160

Inertisation of galvanic sludge with calcium oxide, activated carbon, and phosphoric acid.  

PubMed

In this study we compared three methods for the treatment of electroplating sludge highly loaded with zinc and iron: (1) calcium oxide-based solidification/stabilisation; (2) conversion into inert material by adsorption of organic and inorganic pollutants onto activated carbon; and (3) conversion of mobile waste components into insoluble phosphates. All three methods proved highly efficient in the conversion of hazardous waste into inert material. Under optimum treatment conditions zinc concentration in the leachate of solidified waste was reduced by 99.7 % compared to untreated sludge. Zinc retention efficiency in the waste treated with activated carbon and phosphoric acid was 99.9 % and 98.7 %, respectively. The advantages of electroplating sludge treatment with activated carbon over the other two methods are high sorption capacity, insignificant pH and volume changes of the sludge, and simple use. PMID:23152383

Oreš?anin, Višnja; Lovren?i? Mikeli?, Ivanka; Kollar, Robert; Mikuli?, Nenad; Meduni?, Gordana

2012-09-01

161

Dietary acid load is associated with lower bone mineral density in men with low intake of dietary calcium  

PubMed Central

High dietary acid load (DAL) may be detrimental to bone mineral density (BMD). The objectives of the study were to: 1) evaluate the cross-sectional relation between DAL and BMD; 2) determine whether calcium intake modifies this association. Men (n=1218) and women (n=907) ?60y were included from the National Health and Nutrition Examination Survey 2005–2008. Nutrient intake from 2–24h recalls was used to calculate net endogenous acid production (NEAP) and potential renal acid load (PRAL) (mEq/d). PRAL was calculated from dietary calcium (PRALdiet) and diet + supplemental calcium (PRALtotal). Tests for linear trend in adjusted mean BMD of the hip and lumbar spine were performed across energy adjusted NEAP and PRAL quartiles. Modification by calcium intake (dietary or total) above or below 800 mg/d was assessed by interaction terms. Overall, mean age was 69 ± 0.3y. Among women, there was no association between NEAP and BMD. PRALdiet was positively associated with proximal femur BMD (p trend=0.04). No associations were observed with PRALtotal at any BMD site (P-range: 0.38–0.82). Among men, no significant associations were observed of BMD with NEAP or PRAL. However, an interaction between PRALdiet and calcium intake was observed with proximal femur BMD (p=0.08). An inverse association between PRALdiet and proximal femur BMD was detected among men <800 mg/d dietary calcium (p=0.02); and no associations ?800 mg/d (p=0.98). A significant interaction with PRALtotal was not observed. In conclusion, when supplemental calcium is considered, there is no association between DAL and BMD among adults. Men with low dietary calcium showed an inverse relation with PRAL at the proximal femur; in women no interaction was observed. This study highlights the importance of calcium intakes in counteracting the adverse effect of DAL on bone health. Further research should determine the relation between DAL and change in BMD with very low calcium intake. PMID:23873776

Walsh, Stephen J.; Kenny, Anne M.; Insogna, Karl L.; Kerstetter, Jane E.

2013-01-01

162

Acid-sensing ion channel 3 decreases phosphorylation of extracellular signal-regulated kinases and induces synoviocyte cell death by increasing intracellular calcium  

PubMed Central

Introduction Acid-sensing ion channel 3 (ASIC3) is expressed in synoviocytes, activated by decreases in pH, and reduces inflammation in animal models of inflammatory arthritis. The purpose of the current study was to characterize potential mechanisms underlying the control of inflammation by ASIC3 in fibroblast-like synoviocytes (FLS). Methods Experiments were performed in cultured FLS from wild-type (WT) and ASIC3-/- mice, ASIC1-/- mice, and people with rheumatoid arthritis. We assessed the effects of acidic pH with and without interleukin-1? on FLS and the role of ASICs in modulating intracellular calcium [Ca2+]i, mitogen activated kinase (MAP kinase) expression, and cell death. [Ca2+]i was assessed by fluorescent calcium imaging, MAP kinases were measured by Western Blots; ASIC, cytokine and protease mRNA expression were measured by quantitative PCR and cell death was measured with a LIVE/DEAD assay. Results Acidic pH increased [Ca2+]i and decreased p-ERK expression in WT FLS; these effects were significantly smaller in ASIC3-/- FLS and were prevented by blockade of [Ca2+]i. Blockade of protein phosphatase 2A (PP2A) prevented the pH-induced decreases in p-ERK. In WT FLS, IL-1? increases ASIC3 mRNA, and when combined with acidic pH enhances [Ca2+]i, p-ERK, IL-6 and metalloprotienase mRNA, and cell death. Inhibitors of [Ca2+]i and ERK prevented cell death induced by pH 6.0 in combination with IL-1? in WT FLS. Conclusions Decreased pH activates ASIC3 resulting in increased [Ca2+]i, and decreased p-ERK. Under inflammatory conditions, acidic pH results in enhanced [Ca2+]i and phosphorylation of extracellular signal-regulated kinase that leads to cell death. Thus, activation of ASIC3 on FLS by acidic pH from an inflamed joint could limit synovial proliferation resulting in reduced accumulation of inflammatory mediators and subsequent joint damage. PMID:24923411

2014-01-01

163

Cyclopiazonic acid disturbs the regulation of cytosolic calcium when repetitive action potentials are evoked in Dionaea traps  

Microsoft Academic Search

Evoking of action potentials (APs) in the trap of Dionaea muscipula Ellis at intervals shorter than 20 s caused a gradual decrease in the amplitude of the APs. At longer intervals the amplitude was constant. The calcium ionophore A23187 (1 µM) caused a considerable decrease of AP amplitude. Pretreatment of a segment of the Dionaea trap with cyclopiazonic acid (CPA),

Kazimierz Trebacz; Marion B. Busch; Zygmunt Hejnowicz; Andreas Sievers

1996-01-01

164

Mechanical and rheological properties and injectability of calcium phosphate cement containing poly (lactic-co-glycolic acid) microspheres  

Microsoft Academic Search

To enhance tissue ingrowth and promote rapid resorption, efforts were made to build macropores into calcium phosphate cement (CPC); however, this led to a decrease in its mechanical properties. In this study, poly (lactic-co-glycolic acid) (PLGA) microspheres were incorporated into CPC to impart macroporosity and maintain early strength. The influences of the content of PLGA microspheres on the mechanical strength,

Xiaopeng Qi; Jiandong Ye

2009-01-01

165

The effects of citric and acetic acids on the formation of calcium-deficient hydroxyapatite at 38 °C  

Microsoft Academic Search

This study is concerned with the formation of calcium-deficient hydroxyapatite at physiological temperature. Isothermal calorimetry, solution chemistry, scanning electron microscopy, BET surface area analyses and FTIR spectroscopy were used to characterize the kinetics of HAp formation and the microstructure of the HAp formed in varying concentrations of citric and acetic acids, and in deionized water. The kinetics of HAp formation

K. S. Tenhuisen; P. W. Brown

1994-01-01

166

Calcium Mobilization in Salicylic Acid-Induced Salvia miltiorrhiza Cell Cultures and Its Effect on the Accumulation of Rosmarinic Acid.  

PubMed

Ca(2+) serves as a second messenger in plant responses to different signals, and salicylic acid (SA) has been recognized as a signal mediating plant responses to many stresses. We recently found that SA treatment led to the cytoplasmic acidification of Salvia miltiorrhiza cells and alkalinization of extracellular medium. Here, we demonstrate that SA can rapidly induce Ca(2+) mobilization in protoplasts, but the induction can be blocked with a channel blocker of either plasma or organellar membranes. Following SA, A 23187, or 10 mmol/L Ca(2+) treatment, rosmarinic acid (RA) accumulation reached the highest level at 16 h, whereas the peak was found at 10 h if plasma membrane channel blockers were used. By contrast, the highest accumulation of RA occurred at 16 h when organellar channels were blocked, exhibiting the same tendency with SA-induced cells. In agreement with these observations, both phenylalanine ammonia-lyase (PAL) activity and its gene expression detected by real-time PCR also showed the same patterns. These results indicate that SA treatment firstly results in calcium release from internal stores, which in turn leads to PAL activity increase, RA accumulation, and a large amount of Ca(2+) influx from apoplast after 10 h of SA induction. PMID:25561058

Guo, Hongbo; Zhu, Nan; Deyholos, Michael K; Liu, Jun; Zhang, Xiaoru; Dong, Juane

2015-03-01

167

Inhibition of Aldose Reductase Prevents Endotoxin-Induced Inflammation by Regulating Arachidonic Acid Pathway in Murine Macrophages  

PubMed Central

Bacterial endotoxin, lipopolysaccharide (LPS) is known to induce release of arachidonic acid (AA) and its metabolic products which play important role in inflammatory process. We have shown earlier that LPS-induced signals in macrophages are mediated by aldose reductase (AR). Here we have investigated the role of AR in LPS-induced release of AA metabolites and their modulation using a potent pharmacological inhibitor fidarestat and AR-siRNA ablation in RAW 264.7 macrophages, and AR-knockout mice peritoneal macrophages and heart tissue. Inhibition or genetic ablation of AR prevented the LPS-induced synthesis and release of AA metabolites such as PGE2, TXB, PGI2 and LTBs in macrophages. LPS-induced activation of cPLA2 was also prevented by AR inhibition. Similarly, AR inhibition also prevented the calcium ionophore A23187 –induced cPLA2 and LTB4 in macrophages. Further, AR inhibition with fidarestat prevented the expression of AA metabolizing enzymes such as COX-2 and LOX-5 in RAW 264.7 cells and AR-knockout mice derived peritoneal macrophages. LPS-induced expression of AA metabolizing enzymes and their catalyzed metabolic products were significantly lower in peritoneal macrophages and heart tissue from AR-knockout mice. LPS-induced activation of redox-sensitive signaling intermediates such as MAPKs, transcription factor NF-kB as well as Egr-1, a transcription regulator of mPGES-1, which in collaboration with COX-2 leads to the production of PGE2, were also significantly prevented by AR inhibition. Taken together, our results indicate that AR mediates LPS-induced inflammation by regulating AA metabolic pathway and thus provide novel role of AR inhibition in preventing inflammatory complications such as sepsis. PMID:21856412

Shoeb, Mohammad; Yadav, Umesh CS; Srivastava, Satish K; Ramana, Kota V

2011-01-01

168

Dissolution of steelmaking slags in acetic acid for precipitated calcium carbonate production  

Microsoft Academic Search

A promising option for long-term storage of CO2 is to fixate carbon dioxide as magnesium- and calcium carbonates. Slags from iron and steel works are potential raw materials for carbonation due to their high contents of calcium silicates. Precipitated calcium carbonate (PCC) is used as filler and coating materials in paper. If slag could be used instead of limestone for

Sebastian Teir; Sanni Eloneva; Carl-Johan Fogelholm; Ron Zevenhoven

2007-01-01

169

Calcium-activated gene transfection from DNA/poly(amic acid-co-imide) complexes  

PubMed Central

In this study, we synthesized a water-soluble poly(amic acid-co-imide) (PA-I) from ethylenediaminetetraacetic dianhydride (EDTA) and 2,2?-(ethylenedioxy)bis(ethylamine) that possesses comparable transfection efficiency to that of polyethylenimine (PEI), when prepared in combination with divalent calcium cations. The polycondensation of monomers afforded poly(amic acid) (PA) precursors, and subsequent thermal imidization resulted in the formation of PA-I. At a polymer/DNA ratio (indicated by the molar ratio of nitrogen in the polymer to phosphate in DNA) of 40, complete retardation of the DNA band was observed by gel electrophoresis, indicating the strong association of DNA with PA-I. A zeta potential of ?22 mV was recorded for the PA-I polymer solution, and no apparent cytotoxicity was observed at concentrations up to 500 ?g·mL?1. In the presence of divalent Ca2+, the transfection efficiency of PA-I was higher than that of PA, due to the formation of a copolymer/Ca2+/DNA polyplex and the reduction in negative charge due to thermal cyclization. Interestingly, a synergistic effect of Ca2+ and the synthesized copolymer on DNA transfection was observed. The use of Ca2+ or copolymer alone resulted in unsatisfactory delivery, whereas the formation of three-component polyplexes synergistically increased DNA transfection. Our findings demonstrated that a PA-I/Ca2+/DNA polyplex could serve as a promising candidate for gene delivery.

Wu, Szu-Yuan; Chang, Li-Ting; Peng, Sydeny; Tsai, Hsieh-Chih

2015-01-01

170

Calcium involved in the poly(?-glutamic acid)-mediated promotion of Chinese cabbage nitrogen metabolism.  

PubMed

Plant growth can reportedly be promoted by poly(?-glutamic acid) (?-PGA). However, the underlying mechanism is unknown. To reveal the mechanism of ?-PGA, we designed an experiment that investigated the effect of ?-PGA on the nitrogen metabolism of Chinese cabbage hydroponic cultured at different calcium (Ca) levels and varied exogenous Ca(2+) inhibitors. The results showed that nitrate reductase (NR), glutamine synthetase (GS), glutamate synthase, and glutamate dehydrogenase activities in leaves and roots were obviously enhanced by ?-PGA at the normal Ca(2+) level (4.0 mM). Meanwhile, ?-PGA increased the content of total nitrogen, soluble protein, and soluble amino acids in leaves. However, the promotional effect of ?-PGA on fresh weight weakened when Ca(2+) was inadequate. Moreover, ?-PGA not only induced the influx of extracellular Ca(2+) and Ca(2+) in organelles into cytoplasm, but also increased the Ca(2+)-ATPase level to modify Ca(2+) homeostasis in plant cells. In addition, exogenous Ca(2+) inhibitors significantly suppressed the ?-PGA-mediated promotion of cytoplasmic free Ca(2+) level, calmodulin (CaM) content, GS and glutamate dehydrogenase activities. In summary, ?-PGA accelerated the nitrogen metabolism of plants through the Ca(2+)/CaM signaling pathway, thereby improving the growth of the plant. PMID:24762787

Xu, Zongqi; Lei, Peng; Feng, Xiaohai; Xu, Xianju; Liang, Jinfeng; Chi, Bo; Xu, Hong

2014-07-01

171

Hippuric acid as a significant regulator of supersaturation in calcium oxalate lithiasis: the physiological evidence.  

PubMed

At present, the clinical significance of existing physicochemical and biological evidence and especially the results we have obtained from our previous in vitro experiments have been analyzed, and we have come to the conclusion that hippuric acid (C6H5CONHCH2COOH) is a very active solvent of Calcium Oxalate (CaOX) in physiological solutions. Two types of experiments have been discussed: clinical laboratory analysis on the urine excretion of hippuric acid (HA) in patients with CaOX lithiasis and detailed measurements of the kinetics of the dissolution of CaOX calculi in artificial urine, containing various concentrations of HA. It turns out that the most probable value of the HA concentration in the control group is approximately ten times higher than the corresponding value in the group of the stone-formers. Our in vitro analytical measurements demonstrate even a possibility to dissolve CaOX stones in human urine, in which increased concentration of HA have been established. A conclusion can be that drowning out HA is a significant regulator of CaOX supersaturation and thus a regulation of CaOX stone formation in human urine. Discussions have arisen to use increased concentration of HA in urine both as a solubilizator of CaOX stones in the urinary tract and on the purpose of a prolonged metaphylactic treatment. PMID:24307993

Atanassova, Stoyanka S; Gutzow, Ivan S

2013-01-01

172

Activation of Src and release of intracellular calcium by phosphatidic acid during Xenopus laevis fertilization.  

PubMed

We report a new step in the fertilization in Xenopus laevis which has been found to involve activation of Src tyrosine kinase to stimulate phospholipase C-? (PLC-?) which increases inositol 1,4,5-trisphosphate (IP3) to release intracellular calcium ([Ca](i)). Molecular species analysis and mass measurements suggested that sperm activate phospholipase D (PLD) to elevate phosphatidic acid (PA). We now report that PA mass increased 2.7 fold by 1 min after insemination and inhibition of PA production by two methods inhibited activation of Src and PLC?, increased [Ca](i) and other fertilization events. As compared to 14 other lipids, PA specifically bound Xenopus Src but not PLC?. Addition of synthetic PA activated egg Src (an action requiring intact lipid rafts) and PLC? as well as doubling the amount of PLC? in rafts. In the absence of elevated [Ca](i), PA addition elevated IP3 mass to levels equivalent to that induced by sperm (but twice that achieved by calcium ionophore). Finally, PA induced [Ca](i) release that was blocked by an IP3 receptor inhibitor. As only PLD1b message was detected, and Western blotting did not detect PLD2, we suggest that sperm activate PLD1b to elevate PA which then binds to and activates Src leading to PLC? stimulation, IP3 elevation and [Ca](i) release. Due to these and other studies, PA may also play a role in membrane fusion events such as sperm-egg fusion, cortical granule exocytosis, the elevation of phosphatidylinositol 4,5-bisphosphate and the large, late increase in sn 1,2-diacylglycerol in fertilization. PMID:24269904

Bates, Ryan C; Fees, Colby P; Holland, William L; Winger, Courtney C; Batbayar, Khulan; Ancar, Rachel; Bergren, Todd; Petcoff, Douglas; Stith, Bradley J

2014-02-01

173

Activation of Src and release of intracellular calcium by phosphatidic acid during Xenopus laevis fertilization  

PubMed Central

We report a new step in the fertilization in Xenopus laevis which has been found to involve activation of Src tyrosine kinase to stimulate phospholipase C-? (PLC- ?) which increases inositol 1,4,5-trisphosphate (IP3) to release intracellular calcium ([Ca]i). Molecular species analysis and mass measurements suggested that sperm activate phospholipase D (PLD) to elevate phosphatidic acid (PA). We now report that PA mass increased 2.7 fold by 1 minute after insemination and inhibition of PA production by two methods inhibited activation of Src and PLC?, increased [Ca]i and other fertilization events. As compared to 14 other lipids, PA strongly bound Xenopus Src but not PLC?. Addition of synthetic PA activated egg Src (an action requiring intact lipid rafts) and PLC? as well as doubling the amount of PLC? in rafts. In the absence of elevated [Ca]i, PA addition elevated IP3 mass to levels equivalent to that induced by sperm (but twice that achieved by calcium ionophore). Finally, PA induced [Ca]i release that was blocked by an IP3 receptor inhibitor. As only PLD1b message was detected, and Western blotting did not detect PLD2, we suggest that sperm activate PLD1b to elevate PA which then binds to and activates Src leading to PLC? stimulation, IP3 elevation and [Ca]i release. Due to these and other studies, PA may also play a role in membrane fusion events such as sperm-egg fusion, cortical granule exocytosis, the elevation of phosphatidylinositol 4,5-bisphosphate and the large, late increase in sn 1,2-diacylglycerol in fertilization. PMID:24269904

Bates, Ryan C.; Fees, Colby P.; Holland, William L.; Winger, Courtney C.; Batbayar, Khulan; Ancar, Rachel; Bergren, Todd; Petcoff, Douglas; Stith, Bradley J.

2014-01-01

174

The retention of calcium, barium, and strontium ions by a mollisol humic acid: Spectroscopic investigation  

NASA Astrophysics Data System (ADS)

Humic substances have a major role in controlling the mobility and bioavailability of metallic ions in soils and natural waters. The alkaline earth metals, calcium, barium, and strontium, are broadly abundant in the crust of the earth, and Ca2+ ions are known to be important in the formation of structural aggregates in soils. Yet, direct spectroscopic evidence of how Ca, Ba, and Sr ions interact with soil organic matter, is minimal. To develop a deeper understanding of the interaction of the alkaline earth cations in soil, we studied the complexation behavior of strontium, barium and calcium by humic acid (HA) using solid-state 13C CP-MAS NMR, FTIR and extended x-ray absorption fine structure (EXAFS) spectroscopy. A HA sample was extracted from an agricultural mollisol (pH 6, 32.5% clay content, 3.7% organic carbon) located in southwestern Minnesota, USA, by the standard NaOH method. The HA sample was treated with chloride salts of Ca, Sr or Ba, then freeze-dried prior to spectroscopic measurements. The FTIR spectra, obtained using pressed KBr disks, and the 13C NMR spectra revealed spectral differences, stemming mainly from deprotonation reactions of the carboxylic and phenolic groups of the HA. The association of Ca, Ba, and Sr ions with the HA caused a marked FTIR shift of the carboxylate band, with the Ba shift being the most pronounced (HA 1604.7; HA-Ca 1595.1; HA-Sr 1597; HA-Ba 1579.6), which seems to imply that Ba is the strongest bound element. An NMR shift of the carbonyl peak at 171.8 ppm was also observed to 174.5 for Ca, 173.7 for Sr, and 174.4 for Ba confirming that these cations are behaving differently towards soil HA. The EXAFS spectra indicated back-scattering from oxygen atoms, in the first shell, for Ca, Sr, and Ba with varied coordination number. Our data prove that (1) the carboxylates and phenolates are the prevailing functional groups involved in the interactions between the extracted HA and alkali metal cations, (2) barium forms the strongest complex compared to strontium and calcium.

Oufqir, Sofia; Bloom, Paul R.; Torner, Brandy M.

2014-05-01

175

Zoledronic Acid Prevents Bone Loss During Estrogen-Suppression Treatment of Breast Cancer  

Cancer.gov

Zoledronic acid can prevent treatment-induced bone loss in premenopausal women undergoing total estrogen suppression after surgery for hormone-responsive breast cancer, according to an article published online Jan. 3, 2007, in the Journal of Clinical Oncology.

176

NP04634 prevents cell damage caused by calcium overload and mitochondrial disruption in bovine chromaffin cells.  

PubMed

Marine sponges are becoming a rich source of potential new medicines. NP04634 is a synthetic derivative of 11,19 dideoxyfistularin, a natural product of the Mediterranean sponge Aplysina cavernicola. We report the cytoprotective effects of this new compound in isolated bovine chromaffin cells exposed to cytotoxic stimuli that have been related to neuronal cell death, i.e. Ca(2+) overload and mitochondrial dysfunction. Cell death was achieved by: (i) causing Ca(2+) overload through voltage-dependent calcium channels by exposing the cells to 30 mM K(+), 5 mM Ca(2+) plus 0.3 microM FPL64176 (an L-type Ca(2+)-channel activator); (ii) incubating the cells with veratridine, causing cytosolic Ca(2+) concentration ([Ca(2+)](c)) oscillations and mitochondrial disruption; and (iii) blocking mitochondrial complexes I and V using a combination of 30 microM rotenone and 10 microM oligomycin. At 10 microM, NP04634 caused significant protection against 30K(+)/5Ca(2+)/FPL-induced toxicity. NP04634 caused a concentration-dependent reduction in [Ca(2+)](c) induced by 70 mM K(+) in cells loaded with Fluo-4; maximum blockade was 67% at 30 microM. Veratridine caused continuous [Ca(2+)](c) oscillations that translated into 43.4+/-2% cell death. In this model, NP04634 caused 42% and 67% protection at 3 and 10 microM, respectively. NP04634 reduced [Ca(2+)](c) oscillations and mitochondrial depolarization caused by veratridine. NP04634 at 10 microM also protected against mitochondrial disruption caused by rotenone plus oligomycin. In conclusion, NP04634 is a novel compound of marine origin with cytoprotective properties that might have potential therapeutic implications under pathological circumstances involving Ca(2+) overload and mitochondrial disruption, such as in certain neurodegenerative diseases and/or stroke. PMID:19233161

Valero, Teresa; del Barrio, Laura; Egea, Javier; Cañas, Noelia; Martínez, Ana; García, Antonio G; Villarroya, Mercedes; López, Manuela G

2009-04-01

177

Resveratrol inhibits the intracellular calcium increase and angiotensin/endothelin system activation induced by soluble uric acid in mesangial cells  

PubMed Central

Resveratrol (Resv) is natural polyphenol found in grapes. This study evaluated the protective effect of Resv against the effects of uric acid (UA) in immortalized human mesangial cells (ihMCs). ihMCs were preincubated with Resv (12.5 µM) for 1 h and treated with UA (10 mg/dL) for 6 or 12 h. The intracellular calcium concentration [Ca2+]i was quantified by fluorescence using flow cytometry. Angiotensinogen (AGT) and pre-pro endothelin-1 (ppET-1) mRNA were assayed by quantitative real-time RT-PCR. Angiotensin II (AII) and endothelin-1 (ET-1) were assayed by ELISA. UA significantly increased [Ca2+]i. Pre-incubation with Resv significantly reduced the change in [Ca2+]i induced by UA. Incubation with UA for 6 or 12 h also increased AGT mRNA expression and AII protein synthesis. Resv blunted these increases in AGT mRNA expression and AII protein. Incubation with UA in the ihMCs increased ppET-1 expression and ET-1 protein synthesis at 6 and 12 h. When ihMCs were pre-incubated with Resv, UA had a significantly diminished effect on ppET-1 mRNA expression and ET-1 protein synthesis at 6 and 12 h, respectively. Our results suggested that UA triggers reactions including AII and ET-1 production in mesangial cells. The renin-angiotensin system may contribute to the pathogenesis of renal function and chronic kidney disease. Resv can minimize the impact of UA on AII, ET-1 and the increase of [Ca2+]i in mesangial cells, suggesting that, at least in part, Resv can prevent the effects of soluble UA in mesangial cells. PMID:25493383

Albertoni, G.; Schor, N.

2014-01-01

178

MINE WASTE TECHNOLOGY PROGRAM PREVENTION OF ACID MINE DRAINAGE GENERATION FROM OPEN-PIT HIGHWALLS  

EPA Science Inventory

This document summarizes the results of Mine Waste Technology Program Activity III, Project 26, Prevention of Acid Mine Drainage Generation from Open-Pit Highwalls. The intent of this project was to obtain performance data on the ability of four technologies to prevent the gener...

179

Antimicrobial activity of gallic acid against thermophilic Campylobacter is strain specific and associated with a loss of calcium ions.  

PubMed

Gallic acid has been suggested as a potential antimicrobial for the control of Campylobacter but its effectiveness is poorly studied. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of gallic acid against Campylobacter jejuni (n = 8) and Campylobacter coli (n = 4) strains was determined. Gallic acid inhibited the growth of five C. jejuni strains and three C. coli strains (MIC: 15.63-250 ?g mL(-1)). Gallic acid was only bactericidal to two C. coli strains (MBC: 125 and 62.5 ?g mL(-1)). The mechanism of the bactericidal effect against these two strains (and selected non-susceptible controls) was investigated by determining decimal reduction times and by monitoring the loss of cellular content and calcium ions, and changes in cell morphology. Gallic acid did not result in a loss of cellular content or morphological changes in the susceptible strains as compared to the controls. Gallic acid resulted in a loss of calcium ions (0.58-1.53 ?g mL(-1) and 0.54-1.17 ?g mL(-1), respectively, over a 180 min period) from the susceptible strains but not the controls. Gallic acid is unlikely to be an effective antimicrobial against Campylobacter in a practical sense unless further interventions to ensure an effective bactericidal mode of action against all strains are developed. PMID:25475290

Sarjit, Amreeta; Wang, Yi; Dykes, Gary A

2015-04-01

180

Calcium balance and acid-base status of women as affected by increased protein intake and by sodium bicarbonate ingestion13  

Microsoft Academic Search

Six women, aged 38 to 62 yr. participated in a 40-day metabolic study to investigate the effect of level of protein intake and of sodium bicarbonate ingestion on urinary calcium, net calcium balance, net renal acid excretion, and arterialized venous blood pH and bicarbonate ion concentration. The diet contained 44 g protein during the first 16 days and 102 g

Josephine Lutz

181

Accelerating calcium phosphate growth on NaOH-treated poly-(lactic- co-glycolic acid) by evaporation-induced surface crystallization  

Microsoft Academic Search

Poly(lactic-co-glycolic acid) (PLGA) is a promising material for the regeneration of bone tissue, but its surface properties are not optimal for the application. Coating the surface of PLGA with a continuous layer of calcium phosphate is an effective approach to address the limitation. Current coating techniques for PLGA require immersion in supersaturated calcium phosphate solutions for days to weeks. In

K. Duan; Allen Tang; Rizhi Wang

2008-01-01

182

Folic Acid for the Prevention of Colorectal Adenomas  

Microsoft Academic Search

Results During the first 3 years, 987 participants (96.7%) underwent colonoscopic follow-up, and the incidence of at least 1 colorectal adenoma was 44.1% for folic acid (n=221) and 42.4% for placebo (n=206) (unadjusted risk ratio (RR), 1.04; 95% con- fidence interval (CI), 0.90-1.20; P=.58). Incidence of at least 1 advanced lesion was 11.4% for folic acid (n=57) and 8.6% for

A Randomized Clinical Trial; Bernard F. Cole; John A. Baron; Robert S. Sandler; Robert W. Haile; Dennis J. Ahnen; Robert S. Bresalier; Robert W. Summers; Richard I. Rothstein; Carol A. Burke; Dale C. Snover; Timothy R. Church; John I. Allen; Douglas J. Robertson; Gerald J. Beck; John H. Bond; Tim Byers; Jack S. Mandel; Leila A. Mott; Loretta H. Pearson; Elizabeth L. Barry; Judy R. Rees; Norman Marcon; Fred Saibil; Magne Ueland

2007-01-01

183

?-Aminoisobutyric Acid Prevents Diet-induced Obesity in Mice With Partial Leptin Deficiency  

Microsoft Academic Search

?-Aminoisobutyric acid (BAIBA), a thymine catabolite, increases fatty acid oxidation (FAO) in liver and reduces the gain of body fat mass in Swiss (lean) mice fed a standard chow. We determined whether BAIBA could prevent obesity and related metabolic disorders in different murine models. To this end, BAIBA (100 or 500 mg\\/kg\\/day) was administered for 4 months in mice totally

Karima Begriche; Julie Massart; Adjé Abbey-Toby; Anissa Igoudjil; Philippe Lettéron; Bernard Fromenty

2008-01-01

184

The effect of phosphoric acid concentration on the synthesis of nano-whiskers of calcium metaphosphate by chemical precipitation Method  

NASA Astrophysics Data System (ADS)

Calcium metaphosphate (CMP) nano-whiskers were produced by a chemical precipitation method. In order to produce nano-powders, CMP was prepared by the mixing of two precursors, calcium oxide (CaO) and phosphate acid (H3PO4). Sparingly soluble chemicals, the Ca/P ratio of the mixture was set to be 0.50 to produce stoichiometric CMP, were chemical agitated in phosphate acid solution. At least 3 hours of pre-hydrolysis of phosphorus precursor were required to obtain CMP phase. The CMP powders were dried in a drying oven at 60 °C for 7 days and then followed by a heat treatment at 390 °C for 8hours. The obtained powder was analyzed using XRD, XRF, FT-IR, SEM, TG-DTA, Zeta Potential Meter, Specific Surface Area, and Particle Size Analyzer. The results showed that obtained CMP nano-whiskers have a significantly powder characteristics.

Yao, Nengjian; Zhang, Yin; Kong, Deshuang; Zhu, Jianping; Tao, Yaqiu; Qiu, Tai

2011-10-01

185

Porous poly(DL-lactic-co-glycolic acid)\\/calcium phosphate cement composite for reconstruction of bone defects  

Microsoft Academic Search

Calcium phosphate (Ca-P) cements are injectable, self-setting ceramic pastes generally known for their favorable bone response. Ingrowth of bone and subsequent degradation rates can be enhanced by the inclusion of macropores. Initial porosity can be induced by CO(2) foaming during setting of the cement, whereas secondary porosity can develop after hydrolysis of incorporated poly(DL-lactic- co-glycolic acid) (PLGA) microparticles. In this

P. Quinten Ruhe; E. L. Hedberg; Nestor Torio Padron; Paul H. M. Spauwen; John A. Jansen; Antonios G. Mikos

2006-01-01

186

Changes of extracellular calcium concentration induced by application of excitatory amino acids in the human neocortex in vitro  

Microsoft Academic Search

The influence of the glutamate subreceptor agonists N-methyl-D-aspartate (NMDA) and ?-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) on cortical field potentials and on changes in extracellular free calcium concentration ([Ca2+]o) was tested on human neocortical slices (eleven from nine different patients). The tissue used was a small portion of that which is normally removed for the treatment of a brain tumor. [Ca2+]o and field

A. Lücke; R. Köhling; H. Straub; D. Moskopp; H. Wassmann; E.-J. Speckmann

1995-01-01

187

PTFE-coated foamed glass blocks form a floating tank cover that prevents acid emissions  

SciTech Connect

Foamed glass blocks, coated with a 10-mil thickness of PTFE fluoropolymer, covering open-top tanks that collect 72% sulfuric acid at about 320/sup 0/F, are discussed. The covers are efficient in preventing a mist of sulfuric acid to form over the tanks. The insulating properties have reduced the loss of heat from the tanks. The PTFE coating has not been affected by constant exposure to the acid.

Sandberg, H.W.; Wickersham, C.P.; Gaines, A.

1983-02-01

188

Acid precipitation and food quality: Inhibition of growth and survival in black ducks and mallards by dietary aluminum, calcium, and phosphorus  

Microsoft Academic Search

In areas impacted by acid precipitation, water chemistry of acidic ponds and streams often changes, resulting in increased mobilization of aluminum and decreased concentration of calcium carbonate. Aluminum binds with phosphorus and inhibits its uptake by organisms. Thus, invertebrate food organisms used by waterfowl may have inadequate Ca and P or elevated Al for normal growth and development. Acid rain

Donald W. Sparling

1990-01-01

189

Viability of Listeria monocytogenes on commercially-prepared hams surface treated with acidic calcium sulfate and lauric arginate and stored at 4 °C  

Microsoft Academic Search

We demonstrated the effectiveness of delivering an antimicrobial purge\\/fluid into shrink-wrap bags immediately prior to introducing the product and vacuum sealing, namely the “Sprayed Lethality In Container” (SLIC™) intervention delivery method. The pathogen was Listeria monocytogenes, the antimicrobials were acidic calcium sulfate (ACS; calcium sulfate plus lactic acid; 1:1 or 1:2 in dH2O) and lauric arginate (LAE; Ethyl-N-dodecanoyl-l-arginate hydrochloride; 5%

J. B. Luchansky; J. E. Call; B. Hristova; L. Rumery; L. Yoder; A. Oser

2005-01-01

190

A secondary metabolite, 4,5-dibromopyrrole-2-carboxylic acid, from marine sponges of the genus Agelas alters cellular calcium signals  

Microsoft Academic Search

A secondary metabolite from sponges of the genus Agelas, 4,5-dibromopyrrole-2-carboxylic acid, which is well known as feeding deterrent, was investigated for effects on the cellular calcium homeostasis in PC12 cells. 4,5-Dibromopyrrole-2-carboxylic acid did not change intracellular calcium levels if applied alone without cell depolarization. During depolarization of the cellular membrane using high potassium solution, a dose dependent reduction of intracellular

Ulf Bickmeyer; Michael Assmann; Matthias Köck; Christian Schütt

2005-01-01

191

ISOLATED MEDICAGO TRUNCATULA MUTANTS WITH INCREASED CALCIUM OXALATE CRYSTAL ACCUMULATION HAVE DECREASED ASCORBIC ACID LEVELS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The mechanisms controlling oxalate biosynthesis and calcium oxalate formation in plants remains largely unknown. As an initial step toward gaining insight into these regulatory mechanisms we initiated a mutant screen to identify plants that over-accumulate crystals of calcium oxalate. Four new mut...

192

Development and characterization of an injectable cement of nano calcium-deficient hydroxyapatite/multi(amino acid) copolymer/calcium sulfate hemihydrate for bone repair  

PubMed Central

A novel injectable bone cement was developed by integration of nano calcium-deficient hydroxyapatite/multi(amino acid) copolymer (n-CDHA/MAC) and calcium sulfate hemihydrate (CSH; CaSO4 · 1/2H2O). The structure, setting time, and compressive strength of the cement were investigated. The results showed that the cement with a liquid to powder ratio of 0.8 mL/g exhibited good injectability and appropriate setting time and mechanical properties. In vitro cell studies indicated that MC3T3-E1 cells cultured on the n-CDHA/MAC/CSH composite spread well and showed a good proliferation state. The alkaline phosphatase activity of the MC3T3-E1 cells cultured on the n-CDHA/MAC/CSH composite was significantly higher than that of the cells on pure CSH at 4 and 7 days of culture. The n-CDHA/MAC/CSH cement was implanted into critical size defects of the femoral condyle in rabbits to evaluate its biocompatibility and osteogenesis in vivo. Radiological and histological results indicated that introduction of the n-CDHA/MAC into CSH enhanced new bone formation, and the n-CDHA/MAC/CSH cement exhibited good biocompatibility and degradability. In conclusion, the injectable n-CDHA/MAC/CSH composite cement has a significant clinical advantage over pure CSH cement, and may be a promising bone graft substitute for the treatment of bone defects. PMID:24293996

Qi, Xiaotong; Li, Hong; Qiao, Bo; Li, Weichao; Hao, Xinyan; Wu, Jun; Su, Bao; Jiang, Dianming

2013-01-01

193

Structural and thermotropic properties of calcium-dimyristoylphosphatidic acid complexes at acidic and neutral pH conditions.  

PubMed Central

Two kinds of calcium-dimyristoylphosphatidic acid (DMPA) complexes at acidic and neutral pH conditions were prepared in the following ways. The complex at pH 4 was obtained by adding Ca2+ to DMPA dispersion in pure water. On the other hand, the complex at pH 7.4 was obtained by adding Ca2+ to DMPA dispersion in the presence of NaOH. The stoichiometries of Ca2+ ion to DMPA molecule are 0.5-0.67 and approximately 1 for the complexes at pH 4 and 7.4, respectively. Static x-ray diffraction shows that the hydrocarbon chains of the Ca(2+)-DMPA complex at pH 4 at 20 degrees C are more tightly packed than those of the complex at pH 7.4 at 20 degrees C. Furthermore, the complex at pH 4 at 20 degrees C gives rise to several reflections that might be related to the ordered arrangement of the Ca2+ ions. These results indicate that the structure of the complex at pH 4 is crystalline-like. In the differential scanning calorimetry (DSC) thermogram, the complex at pH 7.4 undergoes no phase transition in a temperature range between 30 and 80 degrees C. On the other hand, in the DSC thermogram for the complex at pH 4, a peak appears at 65.8 degrees C in the first heating scan. In the successive second heating scan, a transition peak appears at 63.5 degrees C. In connection with the DSC results, the structural changes associated with these phase transitions were studied with temperature-scan x-ray diffraction. In the first heating scan, although a peak appears at 65.80C in the DSC thermogram, the hydrocarbon chain packing gradually converts from an orthorhombic lattice to a hexagonal lattice near 52 degree C, and successively the chain melting phase transition occurs near 670C. In the second heating scan, the hydrocarbon chains are packed in a hexagonal lattice over the whole temperature range and the chain melting phase transition occurs near 63.5 degree C. Therefore,the Ca2+-DMPA complex at pH 4 has a metastable state. The metastable state transforms to a stable state by maintaining the complex at pH 4 for about 90 h at 200C. PMID:8534817

Takahashi, H.; Yasue, T.; Ohki, K.; Hatta, I.

1995-01-01

194

The role of calcium in growth induced by indole-3-acetic acid and gravity in the leaf-sheath pulvinus of oat (Avena sativa)  

NASA Technical Reports Server (NTRS)

Leaf-sheath pulvini of excised segments from oat (Avena sativa L.) were induced to grow by treatment with 10 micromoles indole-3-acetic acid (IAA), gravistimulation, or both, and the effects of calcium, EGTA, and calcium channel blockers on growth were evaluated. Unilaterally applied calcium (10 mM CaCl2) significantly inhibited IAA-induced growth in upright pulvini but had no effect on growth induced by either gravity or gravity plus IAA. Calcium alone had no effect on upright pulvini. The calcium chelator EGTA alone (10 mM) stimulated growth in upright pulvini. However, EGTA had no effect on either IAA- or gravity-induced growth but slightly diminished growth in IAA-treated gravistimulated pulvini. The calcium channel blockers lanthanum chloride (25 mM), verapamil (2.5 mM), and nifedipine (2.5 mM) greatly inhibited growth as induced by IAA (> or = 50% inhibition) or IAA plus gravity (20% inhibition) but had no effect on gravistimulated pulvini. Combinations of channel blockers were similar in effect on IAA action as individual blockers. Since neither calcium ions nor EGTA significantly affected the graviresponse of pulvini, we conclude that apoplastic calcium is unimportant in leaf-sheath pulvinus gravitropism. The observation that calcium ions and calcium channel blockers inhibit IAA-induced growth, but have no effect on gravistimulated pulvini, further supports previous observations that gravistimulation alters the responsiveness of pulvini to IAA.

Brock, T. G.; Burg, J.; Ghosheh, N. S.; Kaufman, P. B.

1992-01-01

195

Hydroxyl radical modify amino acids and prevent E. coli growth  

Microsoft Academic Search

The authors report that hydroxyl radical (\\/sup .\\/OH) damage to amino acids (AA) affects their incorporation into E. coli proteins. Modification of AA (Try, Trp, Met, Cys, His, Lys, Asn, Gln) by \\/sup .\\/OH was achieved by exposure to ⁶°Co radiation (1-100 krads at 600 rads\\/min) in NâO saturated water. Following exposure to \\/sup .\\/OH, the modified AA were added

Y. Zhang; K. J. A. Davies

1986-01-01

196

Large procyanidins prevent bile-acid-induced oxidant production and membrane-initiated ERK1/2, p38, and Akt activation in Caco-2 cells.  

PubMed

Procyanidins are oligomers of flavanol subunits present in large amounts in fruits and vegetables. Their consumption is associated with health benefits against colonic inflammation and colorectal cancer (CRC). Large procyanidins (with more than three subunits) are not absorbed by intestinal epithelial cells but could exert biological actions through their interactions with the cell membrane. This study investigated the capacity of hexameric procyanidins (Hex) to prevent oncogenic events initiated by deoxycholic acid (DCA), a secondary bile acid linked to the promotion of CRC. Hex interacted with Caco-2 cell membranes preferentially at the water-lipid interface. Hex (2.5-20 ?M) inhibited DCA-triggered increase in cellular calcium, NADPH oxidase activation, and oxidant production. DCA promoted the activation of protein kinase B (Akt), of the mitogen-activated protein kinases ERK1/2 and p38, and of the downstream transcription factor AP-1. This activation was not triggered by calcium or oxidant increases. Hex caused a dose-dependent inhibition of DCA-mediated activation of all these signals. DCA also triggered alterations in the cell monolayer morphology and apoptotic cell death, events that were delayed by Hex. The capacity of large procyanidins to interact with the cell membrane and prevent those cell membrane-associated events can in part explain the beneficial effects of procyanidins on CRC. PMID:22074817

Da Silva, Mathieu; Jaggers, Grayson K; Verstraeten, Sandra V; Erlejman, Alejandra G; Fraga, Cesar G; Oteiza, Patricia I

2012-01-01

197

[Acid erosions of tooth surface. 3. Prevention and therapy].  

PubMed

Tooth surface loss by erosion presents a challenge to the general practioner in terms of identification of patients at risk, diagnostic investigation and early therapy. The guidelines contain advice for changing the food habits and behaviour in oral hygiene. Patients, who prefer erosive products (fruits, juice, cola) or who vomit should use a bicarbonate mouthrinse to neutralize the acid. The spectrum of therapy reachs of simple fillings with glassionomer cements and composites to comprehensive crown therapy. Several particularities in the psychological care of patients with eating disorders are described. PMID:1818638

Graehn, G

1991-01-01

198

Nucleic Acid Drugs for Prevention of Cardiac Rejection  

PubMed Central

Heart transplantation has been broadly performed in humans. However, occurrence of acute and chronic rejection has not yet been resolved. Several inflammatory factors, such as cytokines and adhesion molecules, enhance the rejection. The graft arterial disease (GAD), which is a type of chronic rejection, is characterized by intimal thickening comprised of proliferative smooth muscle cells. Specific treatments that target the attenuation of acute rejection and GAD formation have not been well studied in cardiac transplantation. Recent progress in the nucleic acid drugs, such as antisense oligodeoxynucleotides (ODNs) to regulate the transcription of disease-related genes, has important roles in therapeutic applications. Transfection of cis-element double-stranded DNA, named as “decoy,” has been also reported to be a useful nucleic acid drug. This decoy strategy has been not only a useful method for the experimental studies of gene regulation but also a novel clinical strategy. In this paper, we reviewed the experimental results of NF-?B, E2F, AP-1, and STAT-1 decoy and other ODNs using the experimental heart transplant models. PMID:20069118

Suzuki, Jun-ichi; Isobe, Mitsuaki; Morishita, Ryuichi; Nagai, Ryozo

2009-01-01

199

21 CFR 172.844 - Calcium stearoyl-2-lactylate.  

Code of Federal Regulations, 2010 CFR

...which is a mixture of calcium salts of stearoyl lactylic acids...proportions of other calcium salts of related acids, is manufactured by the reaction of stearic acid and lactic acid and conversion to the calcium salts. (b) The additive...

2010-04-01

200

21 CFR 172.844 - Calcium stearoyl-2-lactylate.  

Code of Federal Regulations, 2011 CFR

...which is a mixture of calcium salts of stearoyl lactylic acids...proportions of other calcium salts of related acids, is manufactured by the reaction of stearic acid and lactic acid and conversion to the calcium salts. (b) The additive...

2011-04-01

201

21 CFR 172.844 - Calcium stearoyl-2-lactylate.  

Code of Federal Regulations, 2014 CFR

...which is a mixture of calcium salts of stearoyl lactylic acids...proportions of other calcium salts of related acids, is manufactured by the reaction of stearic acid and lactic acid and conversion to the calcium salts. (b) The additive...

2014-04-01

202

21 CFR 172.844 - Calcium stearoyl-2-lactylate.  

Code of Federal Regulations, 2013 CFR

...which is a mixture of calcium salts of stearoyl lactylic acids...proportions of other calcium salts of related acids, is manufactured by the reaction of stearic acid and lactic acid and conversion to the calcium salts. (b) The additive...

2013-04-01

203

21 CFR 172.844 - Calcium stearoyl-2-lactylate.  

Code of Federal Regulations, 2012 CFR

...which is a mixture of calcium salts of stearoyl lactylic acids...proportions of other calcium salts of related acids, is manufactured by the reaction of stearic acid and lactic acid and conversion to the calcium salts. (b) The additive...

2012-04-01

204

Recovery of calcium carbonate from waste gypsum and utilization for remediation of acid mine drainage from coal mines.  

PubMed

The recovery of calcium carbonate from waste gypsum (a waste product of the reverse osmosis (RO) desalination process) was tested using sodium carbonate. Batch recovery of calcium carbonate from waste gypsum slurries by reacting with sodium carbonate under ambient conditions was used to assess the technical feasibility of CaCO(3) recovery and its use for pre-treatment of acid mine drainage (AMD) from coal mines. The effect of key process parameters, such as the slurry concentration (%) and the molar ratio of sodium carbonate to gypsum were considered. It was observed that batch waste gypsum conversion significantly increased with decrease in the slurry concentration or increase in the molar ratio of sodium carbonate to gypsum. The CaCO(3) recovered from the bench-scale batch reactor demonstrated effective neutralization ability during AMD pre-treatment compared with commercial laboratory grade CaCO(3). PMID:22828309

Mulopo, J; Radebe, V

2012-01-01

205

Uric Acid Lowering to Prevent Kidney Function Loss in Diabetes: The Preventing Early Renal Function Loss (PERL) Allopurinol Study  

PubMed Central

Diabetic kidney disease causes significant morbidity and mortality among people with type 1 diabetes (T1D). Intensive glucose and blood pressure control have thus far failed to adequately curb this problem and therefore a major need for novel treatment approaches exists. Multiple observations link serum uric acid levels to kidney disease development and progression in diabetes and strongly argue that uric acid lowering should be tested as one such novel intervention. A pilot of such a trial, using allopurinol, is currently being conducted by the Preventing Early Renal Function Loss (PERL) Consortium. Although the PERL trial targets T1D individuals at highest risk of kidney function decline, the use of allopurinol as a renoprotective agent may also be relevant to a larger segment of the population with diabetes. As allopurinol is inexpensive and safe, it could be cost-effective even for relatively low-risk patients, pending the completion of appropriate trials at earlier stages. PMID:23649945

Maahs, David M.; Caramori, M. Luiza; Cherney, David Z.I.; Galecki, Andrzej T.; Gao, Chuanyun; Jalal, Diana; Perkins, Bruce A.; Pop-Busui, Rodica; Rossing, Peter; Mauer, Michael; Doria, Alessandro

2013-01-01

206

THE ROLE OF GASTRIC ACID IN PREVENTING FOOD BORNE DISEASE AND BACTERIA OVERCOME ACID CONDITIONS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Secretion of hydrochloric acid by the stomach plays an important role in protecting the body against pathogens ingested with food or water. The gastric fluid pH of 1 to 2 is deleterious to many microbial pathogens; however, the neutralization of gastric acid by antacids or the inhibition of acid se...

207

In situ forming hydrogel composed of hyaluronate and polygalacturonic acid for prevention of peridural fibrosis.  

PubMed

Hyaluronic acid-based hydrogels can reduce postoperative adhesion. However, the long-term application of hyaluronic acid is limited by tissue mediated enzymatic degradation. To overcome this limitation, we developed a polygalacturonic acid and hyaluronate composite hydrogel by Schiff's base crosslinking reaction. The polygalacturonic acid and hyaluronate composite hydrogels had short gelation time (less than 15 s) and degraded by less than 50 % in the presence of hyaluronidase for 7 days. Cell adhesion and migration assays showed polygalacturonic acid and hyaluronate composite hydrogels prevented fibroblasts from adhesion and infiltration into the hydrogels. Compared to hyaluronate hydrogels and commercial Medishield™ gels, polygalacturonic acid and hyaluronate composite hydrogel was not totally degraded in vivo after 4 weeks. In the rat laminectomy model, polygalacturonic acid and hyaluronate composite hydrogel also had better adhesion grade and smaller mean area of fibrous tissue formation over the saline control and hyaluronate hydrogel groups. Polygalacturonic acid and hyaluronate composite hydrogel is a system that can be easy to use due to its in situ cross-linkable property and potentially promising for adhesion prevention in spine surgeries. PMID:25791456

Lin, Cheng-Yi; Peng, Hsiu-Hui; Chen, Mei-Hsiu; Sun, Jui-Sheng; Liu, Tse-Ying; Chen, Ming-Hong

2015-04-01

208

Effects of lactic acid and glycolic acid on human osteoblasts: a way to understand PLGA involvement in PLGA/calcium phosphate composite failure.  

PubMed

The use of degradable composite materials in orthopedics remains a field of intense research due to their ability to support new bone formation and degrade in a controlled manner, broadening their use for orthopedic applications. Poly (lactide-co-glycolide) acid (PLGA), a degradable biopolymer, is now a popular material for different orthopedic applications and is proposed for use in tissue engineering scaffolds either alone or combined with bioactive ceramics. Interference screws composed of calcium phosphates and PLGA are readily available in the market. However, some reports highlight problems of screw migration or aseptic cyst formation following screw degradation. In order to understand these phenomena and to help to improve implant formulation, we have evaluated the effects of PLGA degradation products: lactic acid and glycolic acid on human osteoblasts in vitro. Cell proliferation, differentiation, and matrix mineralization, important for bone healing were studied. It was found that the toxicity of polymer degradation products under buffering conditions was limited to high concentrations. However, non-toxic concentrations led to a decrease in cell proliferation, rapid cell differentiation, and mineralization failure. Calcium, whilst stimulating cell proliferation was not able to overcome the negative effects of high concentrations of lactic and glycolic acids on osteoblasts. These effects help to explain recently reported clinical failures of calcium phosphate/PLGA composites, but further in vitro analyses are needed to mimic the dynamic situation which occurs in the body by, for example, culture of osteoblasts with materials that have been pre-degraded to different extents and thus be able to relate these findings to the degradation studies that have been performed previously. PMID:22105618

Meyer, Florent; Wardale, John; Best, Serena; Cameron, Ruth; Rushton, Neil; Brooks, Roger

2012-06-01

209

Characterization of liquid-solid reactions: hydrochloric acid-calcium carbonate reaction  

Microsoft Academic Search

In acidizing techniques, an acid, such as hydrochloric acid, is forced to flow within the pore structure of the rock matrix, or along a hydraulically induced fracture, reacting with the rock and altering reservoir characteristics. A method has been developed of computing the rate of acid spending and the effect of acid reaction on formation flow capacity for the case

B. B. Williams; J. L. Gidley; J. A. Guin; R. S. Schechter

1970-01-01

210

A field study of constructed wetlands for preventing and treating acid mine drainage  

Microsoft Academic Search

The formation of acid mine drainage (AMD) from mine tailings is a severe environmental problem associated with tailings impoundments. The study evaluated the ability of wetlands built on tailings impoundments to prevent AMD formation and to treat already formed AMD, with special emphasis on the role of wetland plants in the remediation process. Four small-scale surface-flow wetlands of different designs,

Johanna Nyquist; Maria Greger

2009-01-01

211

Preventive Effects of Folic Acid Supplementation on Adverse Maternal and Fetal Outcomes  

PubMed Central

Although there is accumulating evidence regarding the additional protective effect of folic acid against adverse pregnancy outcomes other than neural tube defects, these effects have not been elucidated in detail. We evaluated whether folic acid supplementation is associated with favorable maternal and fetal outcomes. This was a secondary analysis of 215 pregnant women who were enrolled in our prior study. With additional data from telephone interviews regarding prenatal folic acid supplementation, existing demographic, maternal and fetal data were statistically analyzed. The concentration of folic acid in maternal blood was significantly higher following folic acid supplementation (24.6 ng/mL vs.11.8 ng/mL). In contrast, homocysteine level in maternal blood decreased with folic acid supplementation (5.5 µmol/mL vs. 6.8 µmol/mL). The rates of both preeclampsia (odds ratio [OR], 0.27; 95% confidence interval [CI], 0.09–0.76) and small for gestational age (SGA; 9.2% vs. 20.0%; OR, 0.42; 95% CI, 0.18–0.99) were lower in the folic acid supplementation group than those in the control group. Other pregnancy outcomes had no association with folic acid supplementation. The findings indicate that folic acid supplementation may help to prevent preeclampsia and SGA. Further studies are warranted to elucidate the favorable effects of folic acid supplementation on pregnancy outcomes. PMID:24842467

Kim, Min Woo; Ahn, Ki Hoon; Ryu, Ki-Jin; Hong, Soon-Cheol; Lee, Ji Sung; Nava-Ocampo, Alejandro A.; Oh, Min-Jeong; Kim, Hai-Joong

2014-01-01

212

Preventive effects of folic acid supplementation on adverse maternal and fetal outcomes.  

PubMed

Although there is accumulating evidence regarding the additional protective effect of folic acid against adverse pregnancy outcomes other than neural tube defects, these effects have not been elucidated in detail. We evaluated whether folic acid supplementation is associated with favorable maternal and fetal outcomes. This was a secondary analysis of 215 pregnant women who were enrolled in our prior study. With additional data from telephone interviews regarding prenatal folic acid supplementation, existing demographic, maternal and fetal data were statistically analyzed. The concentration of folic acid in maternal blood was significantly higher following folic acid supplementation (24.6 ng/mL vs.11.8 ng/mL). In contrast, homocysteine level in maternal blood decreased with folic acid supplementation (5.5 µmol/mL vs. 6.8 µmol/mL). The rates of both preeclampsia (odds ratio [OR], 0.27; 95% confidence interval [CI], 0.09-0.76) and small for gestational age (SGA; 9.2% vs. 20.0%; OR, 0.42; 95% CI, 0.18-0.99) were lower in the folic acid supplementation group than those in the control group. Other pregnancy outcomes had no association with folic acid supplementation. The findings indicate that folic acid supplementation may help to prevent preeclampsia and SGA. Further studies are warranted to elucidate the favorable effects of folic acid supplementation on pregnancy outcomes. PMID:24842467

Kim, Min Woo; Ahn, Ki Hoon; Ryu, Ki-Jin; Hong, Soon-Cheol; Lee, Ji Sung; Nava-Ocampo, Alejandro A; Oh, Min-Jeong; Kim, Hai-Joong

2014-01-01

213

Two Calcium-Dependent Protein Kinases, CPK4 and CPK11, Regulate Abscisic Acid Signal Transduction in Arabidopsis[W  

PubMed Central

Many biochemical approaches show functions of calcium-dependent protein kinases (CDPKs) in abscisic acid (ABA) signal transduction, but molecular genetic evidence linking defined CDPK genes with ABA-regulated biological functions at the whole-plant level has been lacking. Here, we report that ABA stimulated two homologous CDPKs in Arabidopsis thaliana, CPK4 and CPK11. Loss-of-function mutations of CPK4 and CPK11 resulted in pleiotropic ABA-insensitive phenotypes in seed germination, seedling growth, and stomatal movement and led to salt insensitivity in seed germination and decreased tolerance of seedlings to salt stress. Double mutants of the two CDPK genes had stronger ABA- and salt-responsive phenotypes than the single mutants. CPK4- or CPK11-overexpressing plants generally showed inverse ABA-related phenotypes relative to those of the loss-of-function mutants. Expression levels of many ABA-responsive genes were altered in the loss-of-function mutants and overexpression lines. The CPK4 and CPK11 kinases both phosphorylated two ABA-responsive transcription factors, ABF1 and ABF4, in vitro, suggesting that the two kinases may regulate ABA signaling through these transcription factors. These data provide in planta genetic evidence for the involvement of CDPK/calcium in ABA signaling at the whole-plant level and show that CPK4 and CPK11 are two important positive regulators in CDPK/calcium-mediated ABA signaling pathways. PMID:17921317

Zhu, Sai-Yong; Yu, Xiang-Chun; Wang, Xiao-Jing; Zhao, Rui; Li, Yan; Fan, Ren-Chun; Shang, Yi; Du, Shu-Yuan; Wang, Xiao-Fang; Wu, Fu-Qing; Xu, Yan-Hong; Zhang, Xiao-Yan; Zhang, Da-Peng

2007-01-01

214

Nucleotide precursors prevent folic acid-resistant neural tube defects in the mouse  

PubMed Central

Closure of the neural tube during embryogenesis is a crucial step in development of the central nervous system. Failure of this process results in neural tube defects, including spina bifida and anencephaly, which are among the most common birth defects worldwide. Maternal use of folic acid supplements reduces risk of neural tube defects but a proportion of cases are not preventable. Folic acid is thought to act through folate one-carbon metabolism, which transfers one-carbon units for methylation reactions and nucleotide biosynthesis. Hence suboptimal performance of the intervening reactions could limit the efficacy of folic acid. We hypothesized that direct supplementation with nucleotides, downstream of folate metabolism, has the potential to support neural tube closure. Therefore, in a mouse model that exhibits folic acid-resistant neural tube defects, we tested the effect of specific combinations of pyrimidine and purine nucleotide precursors and observed a significant protective effect. Labelling in whole embryo culture showed that nucleotides are taken up by the neurulating embryo and incorporated into genomic DNA. Furthermore, the mitotic index was elevated in neural folds and hindgut of treated embryos, consistent with a proposed mechanism of neural tube defect prevention through stimulation of cellular proliferation. These findings may provide an impetus for future investigations of supplemental nucleotides as a means to prevent a greater proportion of human neural tube defects than can be achieved by folic acid alone. PMID:23935126

Leung, Kit-Yi; De Castro, Sandra C.P.; Savery, Dawn; Copp, Andrew J.

2013-01-01

215

Cancer Preventive Potential of Kimchi Lactic Acid Bacteria (Weissella cibaria, Lactobacillus plantarum)  

PubMed Central

The number of death due to cancer has been increasing in Korea. Chemotherapy is known to cause side effects because it damages not only cancerous cells but healthy cells. Recently, attention has focused on food-derived chemopreventive and anti-tumor agents or formulations with fewer side effects. Kimchi, most popular and widely consumed in Korea, contains high levels of lactic acid bacteria and has been shown to possess chemopreventive effects. This review focuses on Weissella cibaria and Lactobacillus plantarum, the representatives of kimchi lactic acid bacteria, in terms of their abilities to prevent cancer. Further studies are needed to understand the mechanisms by which lactic acid bacteria in kimchi prevent carcinogenic processes and improve immune functions. PMID:25574459

Kwak, Shin-Hye; Cho, Young-Mi; Noh, Geon-Min; Om, Ae-Son

2014-01-01

216

Effects of acid-base disturbances caused by differences in dietary fixed ion balance on kinetics of calcium metabolism in ruminants with high calcium demand.  

PubMed

Effects of subclinical metabolic acid-base disturbances, caused by dietary fixed ion imbalances on kinetics of calcium (Ca) metabolism were examined in eucalcemic caprine does (period 1) and does during simulated lactational Ca loss (period 2). In both experiments, Ca balance data and serial blood, fecal and urine samples were collected after an iv injection of 45Ca. In period 2, lactational Ca loss was simulated by continuous infusion of ethylene glycol-bis (beta-amino ethyl ether)N,N,N'N'-tetraacetic acid (EGTA) to standardize the loss of Ca among goats. The data were fit to a four-compartment model of Ca metabolism. In period 1, fixed anion excess, [sodium + potassium - chloride] = -2 meq/100 g diet dry matter (ANEX) increased urinary Ca excretion relative to fixed cation excess, [sodium + potassium - chloride] = 71 meq/100 g diet dry matter (CATEX). Consequently, rates of Ca absorption and resorption were elevated in goats made acidotic by dietary fixed anion excess. During period 2 (EGTA infusion), urinary Ca loss was elevated to similar levels in goats fed ANEX and CATEX, but Ca absorption remained higher in goats fed ANEX. Consequently, size of the exchangeable Ca pool, accretion rate and balance across bone were higher in these goats. Fixed anion excesses (found in corn silage and grains) cause subclinical metabolic acidosis, which elevates rates of Ca absorption but does not affect size of the exchangeable Ca pool. Fixed cation excesses (associated with diets containing alfalfa and buffers) cause subclinical metabolic alkalosis, which diminishes Ca absorption and urinary Ca excretion. Acidosis-induced hypercalciuria is the metabolic cost of maintaining high prepartum Ca absorption rates and high flux of Ca through the exchangeable Ca pool that may aid in adjustment to sudden Ca losses at parturition. PMID:3366705

Fredeen, A H; DePeters, E J; Baldwin, R L

1988-01-01

217

Bile acids stimulate chloride secretion through CFTR and calcium-activated Cl- channels in Calu-3 airway epithelial cells.  

PubMed

Bile acids resulting from the aspiration of gastroesophageal refluxate are often present in the lower airways of people with cystic fibrosis and other respiratory distress diseases. Surprisingly, there is little or no information on the modulation of airway epithelial ion transport by bile acids. The secretory effect of a variety of conjugated and unconjugated secondary bile acids was investigated in Calu-3 airway epithelial cells grown under an air-liquid interface and mounted in Ussing chambers. Electrogenic transepithelial ion transport was measured as short-circuit current (Isc). The taurine-conjugated secondary bile acid, taurodeoxycholic acid (TDCA), was found to be the most potent modulator of basal ion transport. Acute treatment (5 min) of Calu-3 cells with TDCA (25 ?M) on the basolateral side caused a stimulation of Isc, and removal of extracellular Cl(-) abolished this response. TDCA produced an increase in the cystic fibrosis transmembrane conductance regulator (CFTR)-dependent current that was abolished by pretreatment with the CFTR inhibitor CFTRinh172. TDCA treatment also increased Cl(-) secretion through calcium-activated chloride (CaCC) channels and increased the Na(+)/K(+) pump current. Acute treatment with TDCA resulted in a rapid cellular influx of Ca(2+) and increased cAMP levels in Calu-3 cells. Bile acid receptor-selective activation with INT-777 revealed TGR5 localized at the basolateral membrane as the receptor involved in TDCA-induced Cl(-) secretion. In summary, we demonstrate for the first time that low concentrations of bile acids can modulate Cl(-) secretion in airway epithelial cells, and this effect is dependent on both the duration and sidedness of exposure to the bile acid. PMID:24993131

Hendrick, Siobhán M; Mroz, Magdalena S; Greene, Catherine M; Keely, Stephen J; Harvey, Brian J

2014-09-01

218

Involvement of protein kinase C and protein kinase A in the muscarinic receptor signalling pathways mediating phospholipase C activation, arachidonic acid release and calcium mobilisation.  

PubMed

The involvement of protein kinase C (PKC) and protein kinase A (PKA) in cholinergic signalling in CHO cells expressing the M3 subtype of the muscarinic acetylcholine receptor was examined. Muscarinic signalling was assessed by measuring carbachol-induced activation of phospholipase C (PLC), arachidonic acid release, and calcium mobilisation. Carbachol activation of PLC was not altered by inhibition of PKC with chelerythrine chloride, bisindolylmaleimide or chronic treatment with phorbol myristate acetate (PMA). Activation of PKC by acute treatment with PMA was similarly without effect. In contrast, inhibition of PKC blocked carbachol stimulation of arachidonic acid release. Likewise, PKC inhibition resulted in a decreased ability of carbachol to mobilise calcium, whereas PKC activation potentiated calcium mobilisation. Inhibition of PKA with H89 or Rp-cAMP did not alter the ability of carbachol to activate PLC. Similarly, PKA activation with Sp-cAMP or forskolin had no effect on PLC stimulation by carbachol. Carbachol-mediated release of arachidonic acid was decreased by H89 but only slightly increased by forskolin. Forskolin also increased calcium mobilisation by carbachol. These results suggest a function for PKC and PKA in M3 stimulation of arachidonic acid release and calcium mobilisation but not in PLC activation. PMID:10353692

May, L G; Johnson, S; Krebs, S; Newman, A; Aronstam, R S

1999-03-01

219

Comparative Transcriptome Analysis Reveals Different Molecular Mechanisms of Bacillus coagulans 2-6 Response to Sodium Lactate and Calcium Lactate during Lactic Acid Production  

PubMed Central

Lactate production is enhanced by adding calcium carbonate or sodium hydroxide during fermentation. However, Bacillus coagulans 2-6 can produce more than 180 g/L L-lactic acid when calcium lactate is accumulated, but less than 120 g/L L-lactic acid when sodium lactate is formed. The molecular mechanisms by which B. coagulans responds to calcium lactate and sodium lactate remain unclear. In this study, comparative transcriptomic methods based on high-throughput RNA sequencing were applied to study gene expression changes in B. coagulans 2-6 cultured in non-stress, sodium lactate stress and calcium lactate stress conditions. Gene expression profiling identified 712 and 1213 significantly regulated genes in response to calcium lactate stress and sodium lactate stress, respectively. Gene ontology assignments of the differentially expressed genes were performed. KEGG pathway enrichment analysis revealed that ‘ATP-binding cassette transporters’ were significantly affected by calcium lactate stress, and ‘amino sugar and nucleotide sugar metabolism’ was significantly affected by sodium lactate stress. It was also found that lactate fermentation was less affected by calcium lactate stress than by sodium lactate stress. Sodium lactate stress had negative effect on the expression of ‘glycolysis/gluconeogenesis’ genes but positive effect on the expression of ‘citrate cycle (TCA cycle)’ genes. However, calcium lactate stress had positive influence on the expression of ‘glycolysis/gluconeogenesis’ genes and had minor influence on ‘citrate cycle (TCA cycle)’ genes. Thus, our findings offer new insights into the responses of B. coagulans to different lactate stresses. Notably, our RNA-seq dataset constitute a robust database for investigating the functions of genes induced by lactate stress in the future and identify potential targets for genetic engineering to further improve L-lactic acid production by B. coagulans. PMID:25875592

Qin, Jiayang; Wang, Xiuwen; Wang, Landong; Zhu, Beibei; Zhang, Xiaohua; Yao, Qingshou; Xu, Ping

2015-01-01

220

Effect of surface modification of nanofibres with glutamic acid peptide on calcium phosphate nucleation and osteogenic differentiation of marrow stromal cells.  

PubMed

Biomineralization is mediated by extracellular matrix (ECM) proteins with amino acid sequences rich in glutamic acid. The objective of this study was to investigate the effect of calcium phosphate deposition on aligned nanofibres surface-modified with a glutamic acid peptide on osteogenic differentiation of rat marrow stromal cells. Blend of EEGGC peptide (GLU) conjugated low molecular weight polylactide (PLA) and high molecular weight poly(lactide-co-glycolide) (PLGA) was electrospun to form aligned nanofibres (GLU-NF). The GLU-NF microsheets were incubated in a modified simulated body fluid for nucleation of calcium phosphate crystals on the fibre surface. To achieve a high calcium phosphate to fibre ratio, a layer-by-layer approach was used to improve diffusion of calcium and phosphate ions inside the microsheets. Based on dissipative particle dynamics simulation of PLGA/PLA-GLU fibres, > 80% of GLU peptide was localized to the fibre surface. Calcium phosphate to fibre ratios as high as 200%, between those of cancellous (160%) and cortical (310%) bone, was obtained with the layer-by-layer approach. The extent of osteogenic differentiation and mineralization of marrow stromal cells seeded on GLU-NF microsheets was directly related to the amount of calcium phosphate deposition on the fibres prior to cell seeding. Expression of osteogenic markers osteopontin, alkaline phosphatase (ALP), osteocalcin and type 1 collagen increased gradually with calcium phosphate deposition on GLU-NF microsheets. Results demonstrate that surface modification of aligned synthetic nanofibres with EEGGC peptide dramatically affects nucleation and growth of calcium phosphate crystals on the fibres leading to increased osteogenic differentiation of marrow stromal cells and mineralization. Copyright © 2013 John Wiley & Sons, Ltd. PMID:23897753

Karaman, Ozan; Kumar, Ankur; Moeinzadeh, Seyedsina; He, Xuezhong; Cui, Tong; Jabbari, Esmaiel

2013-07-30

221

[Occlusion of central venous port catheters after simultaneous 24 h infusions of 5-FU and calcium-folinic acid in patients with gastrointestinal cancer].  

PubMed

Folinic acid-modulated 5-FU regimens are standard elements in several chemotherapy combinations like FOLFIRI, FOLFOX or AIO-regimen in the palliative treatment of patients with gastrointestinal cancer. When the simultaneous mixed infusion of 5-FU and calcium-folinic acid (Leucovorin) was authorized by the BfArM in 2002, we introduced this application regimen in the treatment of our cancer patients. 19 patients (AIO-regimen [5], FOLFIRI [12] and FOLFOX [2]) received a simultaneously mixed infusion of calcium-folinic acid and 5-FU over 24 hours with a total of 110 applications. 5-FU doses varied between 2000 and 2600 mg/m2, calcium-folinic acid was given with 500 mg/m2, infusion rate was 10 ml/hour using a 24 h pump. Central venous catheters employed included single Barth-Port in 18 cases, 1 patient had a Viggon-Port. In 3 out of the 19 patients catheter occlusion was noticed after 8-10 weekly applications of the mixed infusion. Heparine and subsequently urokinase were not successful in reversing the obstruction. All three catheters had to be explanted. Catheter tips in all cases showed a yellow cristalline precipitation. The crystallographic analysis exhibited calcium carbonate (CaCO3) in its polymorphic form (calcite). Thus, we confirmed calcite formation causing catheter occlusion as a frequent complication during a continuous 24 h-infusion of mixed high dose 5-FU and calcium-folinic acid. This reaction could not be avoided by increasing infusion volume and the application flow rate. As a result of our findings, recommending using calcium-folinic acid mixed with 5-FU has been withdrawn in the meantime. PMID:15244042

Fackler-Schwalbe, I; Schwalbe, B; Epple, M; Becker, A; Prügl, L; Gassel, W D; Stoffels, D; Südhoff, T

2004-05-01

222

The Effect of varying ratios of docosahexaenoic Acid and arachidonic acid in the prevention and reversal of biochemical essential fatty acid deficiency in a murine model  

PubMed Central

Objective Essential fatty acids (EFA) are necessary for growth, development, and biological function, and must be acquired through the diet. While linoleic acid (LA) and alpha-linolenic acid (ALA) have been considered the true EFAs, we previously demonstrated that docosahexaenoic acid (DHA) and arachidonic acid (AA) taken together as the sole source of dietary fatty acids can prevent biochemical essential fatty acid deficiency (EFAD). This study evaluates the effect of varying dietary ratios of DHA:AA in the prevention and reversal of biochemical EFAD in a murine model. Methods Using a murine model of EFAD, we provided mice with 2.1% of daily caloric intake in varying DHA:AA ratios (1:1, 5:1, 10:1, 20:1, 200:1, 100:0) for 19 days in association with a liquid high-carbohydrate fat-free diet to evaluate the effect on fatty acid profiles. In a second experiment, we evaluated the provision of varying DHA:AA ratios (20:1, 200:1, 100:0) on the reversal of biochemical EFAD. Results Mice provided with DHA and AA had no evidence of biochemical EFAD, regardless of the ratio (1:1, 5:1, 10:1, 20:1, 200:1, 100:0) administered. Biochemical EFAD was reversed with DHA:AA ratios of 20:1, 200:1, and 100:0 following 3 and 5 weeks of dietary provision, although the 20:1 ratio was most effective in the reversal and stabilization of the triene:tetraene ratio. Conclusion Provision of DHA and AA, at 2.1% of daily caloric intake in varying ratios can prevent biochemical evidence of EFAD and hepatic steatosis over the short-term, with a ratio of 20:1 DHA:AA most effectively reversing EFAD. PMID:23151438

Le, Hau D.; Fallon, Erica M.; Kalish, Brian T.; de Meijer, Vincent E.; Meisel, Jonathan A.; Gura, Kathleen M.; Nose, Vania; Pan, Amy H.; Bistrian, Bruce R.; Puder, Mark

2012-01-01

223

Randomized Controlled Trial of a Low Animal Protein, High Fiber Diet in the Prevention of Recurrent Calcium Oxalate Kidney Stones  

Microsoft Academic Search

Low protein diets are commonly prescribed for patients with idiopathic calcium nephrolithiasis, who account for >80% of new diagnoses of kidney stones. This dietary advice is supported by metabolic studies and epidemiologic observational studies but has not been evaluated in a controlled trial. Using 1983-1985 data from three Northern California Kaiser Permanente Medical Centers, the authors randomly assigned 99 persons

Robert A. Hiatt; Bruce Ettinger; Bette Caan; Charles P. Quesenberry; Debra Duncan; John T. Citron

224

Docosahexaenoic acid and butyrate synergistically modulate intracellular calcium compartmentalization to induce colonocyte apoptosis  

E-print Network

Docosahexaenoic acid (DHA, 22:6n-3) from fish oil, and butyrate, a short-chain fatty acid fiber-fermentation product, protect against colon tumorigenesis in part by coordinately inducing apoptosis. We have demonstrated that the combination...

Kolar, Satya Sree N.

2009-05-15

225

Pretreatment of solid carbonaceous material with dicarboxylic aromatic acids to prevent scale formation  

DOEpatents

Scale formation during the liquefaction of lower ranking coals and similar carbonaceous materials is significantly reduced and/or prevented by pretreatment with a pretreating agent selected from the group consisting of phthalic acid, phthalic anhydride, pyromellitic acid and pyromellitic anhydride. The pretreatment is believed to convert the scale-forming components to the corresponding phthalate and/or pyromellitate prior to liquefaction. The pretreatment is accomplished at a total pressure within the range from about 1 to about 2 atmospheres. Temperature during pretreatment will generally be within the range from about 5.degree. to about 80.degree. C.

Brunson, Roy J. (Buffalo Grove, IL)

1982-01-01

226

Calcium carbonate crystal growth beneath Langmuir monolayers of acidic ?-hairpin peptides.  

PubMed

Four amphiphilic peptides with designed hairpin structure were synthesized and their monolayers were employed as model systems to study biologically inspired calcium carbonate crystallization. Langmuir monolayers of hairpin peptides were investigated by surface pressure area isotherms, surface potential isotherms, Brewster angle microscopy (BAM), atomic force microscopy (AFM) and Fourier transform infrared (FTIR) spectroscopy. A ?-hairpin conformation was found for all peptides at the air-water interface although their packing arrangements seem to be different. Crystallization of calcium carbonate under these peptide monolayers was investigated at different surface pressures and growth times both by in situ optical microscopy, BAM and ex situ investigations such as scanning electron microscopy (SEM) and transmission electron microscopy (TEM). An amorphous calcium carbonate precursor was found at the initial crystallization stage. The crystallization process occurred in three stages. It starts from the nucleation of amorphous particles being a kinetically controlled process. Crystal nuclei subsequently aggregate to large particles and vaterite crystals start to form inside the amorphous layer, with the monolayer fluidity exerting an important role. The third process includes the re-crystallization of vaterite to calcite, which is thermodynamically controlled by monolayer structural factors including the monolayer flexibility and packing arrangement of the polar headgroups. Thus, the kinetic factors, monolayer fluidity and flexibility as well as structure factors govern the crystal morphology and polymorph distribution simultaneously and synergistically. PMID:25292256

Gong, Haofei; Yang, Yi; Pluntke, Manuela; Marti, Othmar; Majer, Zsuzsa; Sewald, Norbert; Volkmer, Dirk

2014-11-28

227

Biotransformation of dehydroabietic acid with resting cell suspensions and calcium alginate-immobilized cells of Mortierella isabellina.  

PubMed Central

Mortierella isabellina ATCC 38063 is a zygomycete capable of hydroxylating fish-toxic resin acids which occur in certain pulp mill effluents to nontoxic metabolites. Addition of dehydroabietic acid (1) (80 mg/liter) to a freshly inoculated culture of M. isabellina in dextrose-yeast extract broth resulted in precursor disappearance in 28 to 30 h. During growth phase, hydroxylation occurred at C-2, whereas hydroxylation at C-15 and C-16 commenced with onset of stationary phase. Alternatively, 1 added to stationary-phase culture (40 mg/liter) disappeared within 2 h and hydroxylation occurred concurrently at C-2, C-15, and C-16. Enzymatic activity of stationary-phase culture was totally cell associated and was present despite the absence of 1 during the preparatory growth phase. Resuspension of mature fungi as free mycelia or immobilized in calcium alginate beads did not diminish the effectiveness of the biotransformation, although two new metabolites, 15-hydroxy-8,9,11,12-tetradehydro-7,8-dihydroabietic acid (5) and 16-hydroxy-8,9,11,12-tetradehydro-7,8-dihydroabietic acid (7) were formed. Immobilized mycelia retained hydroxylase activity for greater than 110 days whether or not they were challenged with fresh 1 on a regular basis. In this respect they are more long-lived than resuspended free mycelia are. PMID:3883900

Kutney, J P; Choi, L S; Hewitt, G M; Salisbury, P J; Singh, M

1985-01-01

228

Hyaluronic Acid\\/Carboxymethylcellulose Membrane Barrier versus Taurolidine for the Prevention of Adhesions to Polypropylene Mesh  

Microsoft Academic Search

Background: A hyaluronic acid\\/carboxymethylcellulose (HA\\/CMC) membrane is an effective measure to prevent polypropylene mesh induced adhesions. We hypothesized that taurolidine 2% solution might be a cost-effective alternative to decrease adhesion formation. Materials and Methods: Twenty-four rats were randomized into three groups: mesh alone (group 1), mesh + taurolidine 2% (group 2), and mesh + HA\\/CMC (group 3). Polypropylene mesh (4

Hakan Erpek; Pars Tuncyurek; Aykut Soyder; Sukru Boylu

2006-01-01

229

Alpha-lipoic acid prevents mitochondrial damage and neurotoxicity in experimental chemotherapy neuropathy.  

PubMed

The study investigates if alpha-lipoic acid is neuroprotective against chemotherapy induced neurotoxicity, if mitochondrial damage plays a critical role in toxic neurodegenerative cascade, and if neuroprotective effects of alpha-lipoic acid depend on mitochondria protection. We used an in vitro model of chemotherapy induced peripheral neuropathy that closely mimic the in vivo condition by exposing primary cultures of dorsal root ganglion (DRG) sensory neurons to paclitaxel and cisplatin, two widely used and highly effective chemotherapeutic drugs. This approach allowed investigating the efficacy of alpha-lipoic acid in preventing axonal damage and apoptosis and the function and ultrastructural morphology of mitochondria after exposure to toxic agents and alpha-lipoic acid. Our results demonstrate that both cisplatin and paclitaxel cause early mitochondrial impairment with loss of membrane potential and induction of autophagic vacuoles in neurons. Alpha-lipoic acid exerts neuroprotective effects against chemotherapy induced neurotoxicity in sensory neurons: it rescues the mitochondrial toxicity and induces the expression of frataxin, an essential mitochondrial protein with anti-oxidant and chaperone properties. In conclusion mitochondrial toxicity is an early common event both in paclitaxel and cisplatin induced neurotoxicity. Alpha-lipoic acid protects sensory neurons through its anti-oxidant and mitochondrial regulatory functions, possibly inducing the expression of frataxin. These findings suggest that alpha-lipoic acid might reduce the risk of developing peripheral nerve toxicity in patients undergoing chemotherapy and encourage further confirmatory clinical trials. PMID:18809400

Melli, Giorgia; Taiana, Michela; Camozzi, Francesca; Triolo, Daniela; Podini, Paola; Quattrini, Angelo; Taroni, Franco; Lauria, Giuseppe

2008-12-01

230

Maintenance of an acidic stratum corneum prevents emergence of murine atopic dermatitis.  

PubMed

Neutralization of stratum corneum (SC) adversely impacts key epidermal functions, including permeability barrier homeostasis and SC integrity. Conversely, acidification of SC improves these functions in developmentally impaired (neonatal or aged) skin, and enhances function in normal skin. Hence, we hypothesized that acidification could alter the course of inflammatory dermatoses, which invariably exhibit an increased SC pH. Maintenance of a low pH by topical applications of the polyhydroxyl acid, lactobionic acid, during the repeated-challenge phase inhibited the development of oxazolone-induced atopic dermatitis (AD). Neither gross/histological dermatitis nor altered barrier function developed, and emergence of epidermal hyperplasia was prevented; however, cytokine generation decreased. Acidification also largely normalized the development of hapten-induced changes in eosinophil/mast cell densities, density of chemoattractant receptor-homologous molecule expressed on TH2-positive lymphocytes, and serum IgE levels. The pH-induced improvement in barrier function most likely accounts for the anti-inflammatory activity, which could be further attributed to normalization of both lamellar body secretion and lamellar bilayer formation. Acidification of SC alone substantially prevents development of barrier abnormalities and downstream immune abnormalities during the elicitation phase of murine AD. These results provide direct evidence for the "outside-inside" pathogenesis of AD and further suggest that maintenance of an acidic SC pH could prevent the emergence of AD in humans. PMID:19177139

Hatano, Yutaka; Man, Mao-Qiang; Uchida, Yoshikazu; Crumrine, Debra; Scharschmidt, Tiffany C; Kim, Esther G; Mauro, Theodora M; Feingold, Kenneth R; Elias, Peter M; Holleran, Walter M

2009-07-01

231

Maintenance of an Acidic Stratum Corneum Prevents Emergence of Murine Atopic Dermatitis  

PubMed Central

Neutralization of stratum corneum (SC) adversely impacts key epidermal functions, including permeability barrier homeostasis and SC integrity. Conversely, acidification of SC improves these functions in developmentally impaired (neonatal or aged) skin, and enhances function in normal skin. Hence, we hypothesized that acidification could alter the course of inflammatory dermatoses, which invariably exhibit an increased SC pH. Maintenance of a low pH by topical applications of the polyhydroxyl acid, lactobionic acid, during the repeated-challenge phase inhibited the development of oxazolone-induced atopic dermatitis (AD). Neither gross/histological dermatitis nor altered barrier function developed, and emergence of epidermal hyperplasia was prevented; however, cytokine generation decreased. Acidification also largely normalized the development of hapten-induced changes in eosinophil/mast cell densities, density of chemoattractant receptor-homologous molecule expressed on TH2-positive lymphocytes, and serum IgE levels. The pH-induced improvement in barrier function most likely accounts for the anti-inflammatory activity, which could be further attributed to normalization of both lamellar body secretion and lamellar bilayer formation. Acidification of SC alone substantially prevents development of barrier abnormalities and downstream immune abnormalities during the elicitation phase of murine AD. These results provide direct evidence for the “outside–inside” pathogenesis of AD and further suggest that maintenance of an acidic SC pH could prevent the emergence of AD in humans. PMID:19177139

Hatano, Yutaka; Man, Mao-Qiang; Uchida, Yoshikazu; Crumrine, Debra; Scharschmidt, Tiffany C.; Kim, Esther G.; Mauro, Theodora M.; Feingold, Kenneth R.; Elias, Peter M.; Holleran, Walter M.

2009-01-01

232

Partitioning of polyunsaturated fatty acids, which prevent cardiac arrhythmias, into phospholipid cell membranes.  

PubMed

It has been demonstrated in animal studies that polyunsaturated fatty acids (PUFA) prevent ischemia-induced malignant ventricular arrhythmias, a major cause of sudden cardiac death in humans. To learn how these PUFA, at low micromolar concentrations, exert their antiarrhythmic activity, we studied their effects in vitro on the contractions of isolated cardiac myocytes and the conductances of their sarcolemmal ion channels. These fatty acids directly stabilize electrically every cardiac myocyte by modulating the conductances of specific ion channels in their sarcolemma. In this study, we determined the molar ratio of PUFA to the moles of phospholipid (PL) in cell membranes to learn if the ratio is so low as to preclude the possibility that the primary site of action of PUFA is on the packing of the membrane PL. [(3)H]-arachidonic acid (AA) was used to measure the incorporation of PUFA, and the inorganic phosphorous of the PL was determined as a measure of the moles of PL in the cell membrane. Our results indicate that the mole percent of AA to moles of phospolipid is very low (< or =1.0) at the concentrations that affect myocyte contraction and the conductance of voltage-dependent Na(+) and L-type Ca(2)+ channels in rat cardiomyocytes and in alpha-subunits of human myocardial Na(+) channels. In conclusion, it seems highly unlikely that these fatty acids are affecting the packing of PL within cell membranes as their way of modulating changes in cell membrane ion currents and in preventing arrhythmias in our contractility studies. -- Pound, E. M., J. X. Kang, and A. Leaf. Partitioning of polyunsaturated fatty acids, which prevent cardiac arrhythmias, into phospholipid cell membranes. J. Lipid Res. 2001. 42: 346--351. PMID:11254745

Pound, E M; Kang, J X; Leaf, A

2001-03-01

233

Kallikrein expression and cathelicidin processing are independently controlled in keratinocytes by calcium, vitamin D(3), and retinoic acid.  

PubMed

Cathelicidin has dual functions in the skin, acting as an innate antibiotic and as an immunomodulator in diseases such as rosacea and psoriasis. The serine proteases kallikrein 5 (KLK5) and kallikrein 7 (KLK7) control enzymatic processing of cathelicidin precursor in the skin and regulate the eventual function of the final forms of these peptides. We analyzed factors that control expression of KLK5 and KLK7 in normal human epidermal keratinocytes to better understand how these may influence cathelicidin processing and function. Increased extracellular calcium-induced KLK5 and KLK7 mRNA expression and protein release in a time-dependent manner that is similar to induction of differentiation markers such as keratin 10 and involucrin. However, 1,25(OH)(2) vitamin D(3), 9-cis retinoic acid (RA), and 13-cis RA also induced the KLKs, but the timing and pattern of KLK induction for each were different and distinct from changes in differentiation markers. Increased protease activity and differential processing of cathelicidin accompanied increased KLK expression. These findings show that the expression and activity of KLK are under fine control and can be distinctly influenced by variables such as differentiation, calcium, vitamin D, and RA. Thus, these variables may further control the functions of antimicrobial peptides in the skin. PMID:20090765

Morizane, Shin; Yamasaki, Kenshi; Kabigting, Filamer D; Gallo, Richard L

2010-05-01

234

Prolonged Diuretic Activity and Calcium-Sparing Effect of Tropaeolum majus: Evidence in the Prevention of Osteoporosis  

PubMed Central

Although several studies indicate high effectiveness in the use of the hydroethanolic extract from Tropaeolum majus (HETM) as a diuretic, the impact of its prolonged use in the presence of low estrogen levels remains unclear. Thus, the aim of this study was to investigate the diuretic effects of prolonged administration of HETM in ovariectomized rats and their interrelationship between calcium excretion and bone turnover. Forty-two female Wistar rats were ovariectomized (OVX) and treated orally with different doses of HETM (3, 30, and 300?mg/kg) for 4 weeks. On the first day of treatment and at weekly intervals for four weeks the diuretic activity was evaluated. Electrolyte concentrations and creatinine levels were estimated from urine sample of each rat. The serum lipids, urea, creatinine, and osteocalcin were also measured at the end of the experiment. The data revealed that the HETM was able to sustain its diuretic effect after prolonged treatment. Moreover, its use has not affected the urinary calcium or potassium excretion, reduces lipid levels, and maintains osteocalcin levels similarly to untreated rats. These findings support the potential of HETM as a candidate to be used in clinical conditions in which the renal loss of calcium is not desired. PMID:25028592

Barboza, Lorena Neris; Prando, Thiago Bruno Lima; Dalsenter, Paulo Roberto; Gasparotto, Francielly Mourão; Gasparotto, Francielli; Jacomassi, Ezilda; Araújo, Valdinei de Oliveira; Lourenço, Emerson Luiz Botelho; Gasparotto Junior, Arquimedes

2014-01-01

235

Prolonged Diuretic Activity and Calcium-Sparing Effect of Tropaeolum majus: Evidence in the Prevention of Osteoporosis.  

PubMed

Although several studies indicate high effectiveness in the use of the hydroethanolic extract from Tropaeolum majus (HETM) as a diuretic, the impact of its prolonged use in the presence of low estrogen levels remains unclear. Thus, the aim of this study was to investigate the diuretic effects of prolonged administration of HETM in ovariectomized rats and their interrelationship between calcium excretion and bone turnover. Forty-two female Wistar rats were ovariectomized (OVX) and treated orally with different doses of HETM (3, 30, and 300?mg/kg) for 4 weeks. On the first day of treatment and at weekly intervals for four weeks the diuretic activity was evaluated. Electrolyte concentrations and creatinine levels were estimated from urine sample of each rat. The serum lipids, urea, creatinine, and osteocalcin were also measured at the end of the experiment. The data revealed that the HETM was able to sustain its diuretic effect after prolonged treatment. Moreover, its use has not affected the urinary calcium or potassium excretion, reduces lipid levels, and maintains osteocalcin levels similarly to untreated rats. These findings support the potential of HETM as a candidate to be used in clinical conditions in which the renal loss of calcium is not desired. PMID:25028592

Barboza, Lorena Neris; Prando, Thiago Bruno Lima; Dalsenter, Paulo Roberto; Gasparotto, Francielly Mourão; Gasparotto, Francielli; Jacomassi, Ezilda; Araújo, Valdinei de Oliveira; Lourenço, Emerson Luiz Botelho; Gasparotto Junior, Arquimedes

2014-01-01

236

Polished rice as natural sources of cancer-preventing geranylgeranoic acid  

PubMed Central

Geranylgeranoic acid, a 20-carbon polyprenoic acid (all-trans 3,7,11,15-tetramethyl-2,4,6,10,14-hexadecatetraenoic acid) and its derivatives were previously developed as synthetic “acyclic retinoids” for cancer chemoprevention. Recently, we demonstrated the natural occurrence of geranylgeranoic acid in various medicinal herbs (Shidoji and Ogawa, 2004). In this present study, we present several lines of evidence to demonstrate that geranylgeranyl diphosphate taken in foods could be metabolized to GGA through geranylgeraniol and geranylgeranyl aldehyde via the following steps: 1) The conversion from geranylgeranyl diphosphate to geranylgeraniol was demonstrated to occur by the action of bovine intestinal alkaline phosphatase, with a Km of 46.1 µM. 2) Geranylgeraniol oxidase-mediated conversion of geranylgeraniol to geranylgeranyl aldehyde was revealed in rat liver homogenates, which activity was mainly localized in the mitochondrial fraction. The mitochondrial enzyme showed a Km of 92.9 µM. 3) The conversion of geranylgeranyl aldehyde to geranylgeranoic acid by geranylgeranyl aldehyde dehydrogenase in rat liver homogenates was absolutely dependent on exogenously added NAD+ or NADP+. The Km of the mitochondrial geranylgeranyl aldehyde dehydrogenase was 27.5 µM for geranylgeranyl aldehyde. Taken together, our data suggest that cancer preventive geranylgeranoic acid could be a physiological metabolite from commonly consumed foods. PMID:21765600

Muraguchi, Takashi; Okamoto, Kyoko; Mitake, Maiko; Ogawa, Hiroko; Shidoji, Yoshihiro

2011-01-01

237

Biosynthesis of l-Ascorbic Acid and Conversion of Carbons 1 and 2 of l-Ascorbic Acid to Oxalic Acid Occurs within Individual Calcium Oxalate Crystal Idioblasts1  

PubMed Central

l-Ascorbic acid (AsA) and its metabolic precursors give rise to oxalic acid (OxA) found in calcium oxalate crystals in specialized crystal idioblast cells in plants; however, it is not known if AsA and OxA are synthesized within the crystal idioblast cell or transported in from surrounding mesophyll cells. Isolated developing crystal idioblasts from Pistia stratiotes were used to study the pathway of OxA biosynthesis and to determine if idioblasts contain the entire path and are essentially independent in OxA synthesis. Idioblasts were supplied with various 14C-labeled compounds and examined by micro-autoradiography for incorporation of 14C into calcium oxalate crystals. [14C]OxA gave heavy labeling of crystals, indicating the isolated idioblasts are functional in crystal formation. Incubation with [1-14C]AsA also gave heavy labeling of crystals, whereas [6-14C]AsA gave no labeling. Labeled precursors of AsA (l-[1-14C]galactose; d-[1-14C]mannose) also resulted in crystal labeling, as did the ascorbic acid analog, d-[1-14C]erythorbic acid. Intensity of labeling of isolated idioblasts followed the pattern OxA > AsA (erythorbic acid) > l-galactose > d-mannose. Our results demonstrate that P. stratiotes crystal idioblasts synthesize the OxA used for crystal formation, the OxA is derived from the number 1 and 2 carbons of AsA, and the proposed pathway of ascorbic acid synthesis via d-mannose and l-galactose is operational in individual P. stratiotes crystal idioblasts. These results are discussed with respect to fine control of calcium oxalate precipitation and the concept of crystal idioblasts as independent physiological compartments. PMID:11161021

Kostman, Todd A.; Tarlyn, Nathan M.; Loewus, Frank A.; Franceschi, Vincent R.

2001-01-01

238

21 CFR 184.1201 - Calcium glycerophosphate.  

Code of Federal Regulations, 2012 CFR

...hygroscopic powder. It is prepared by neutralizing glycerophosphoric acid with calcium hydroxide or calcium carbonate. The commercial product is a mixture of calcium ?-, and D-, and L -?-glycerophosphate. (b) The...

2012-04-01

239

21 CFR 184.1201 - Calcium glycerophosphate.  

Code of Federal Regulations, 2010 CFR

...hygroscopic powder. It is prepared by neutralizing glycerophosphoric acid with calcium hydroxide or calcium carbonate. The commercial product is a mixture of calcium ?-, and D-, and L -?-glycerophosphate. (b) The...

2010-04-01

240

Preliminary evaluation of effects of invasive tunicate management with acetic acid and calcium hydroxide on non-target marine organisms in Prince Edward Island, Canada  

Microsoft Academic Search

The proliferation of invasive tunicates in Prince Edward Island (PEI) estuaries has necessitated the development of approaches for managing tunicates that foul aquaculture structures, especially Styela clava and Ciona intestinalis. Spraying or immersion with a saturated solution of hydrated lime (calcium hydroxide) or 5% acetic acid are effective against these tunicates, but are also biocidal to a variety of non-target

Andrea Locke; Kenneth G. Doe; Wayne L. Fairchild; Paula M. Jackman; Erica J. Reese

2009-01-01

241

Human milk beyond one year post-partum: lower content of protein, calcium, and saturated very long-chain fatty acids.  

PubMed

Maternal milk feeding for more than 1 year is encouraged by many health care authorities. We demonstrate that human milk beyond 1 year of lactation had a small but significantly lower concentration of protein, calcium, and long-chain saturated fatty acids compared with human milk at 3 months after delivery. PMID:16423611

Shehadeh, Naim; Aslih, Nardin; Shihab, Shihab; Werman, Moshe J; Sheinman, Rivkah; Shamir, Raanan

2006-01-01

242

Calcium sulfate crystallization along citrus root channels in a Florida soil exhibiting acid sulfate properties  

SciTech Connect

The authors observed euhedral crystals in Manatee soil in a citrus grove in St. Lucie County, Florida. The material was identified as gypsum (CaSO/sub 4/ /times/ 2H/sub 2/O) using x-ray diffraction and infrared spectra. Photomicrography and scanning electron microscopy revealed that gypsum accumulated both in old root channels and within citrus root tissue of the Btg horizon. The subsurface horizons had elevated sulfate levels, a low initial pH, a drop (0.5 unit) in pH upon air-drying. Electrical conductivity paralleled the concentration of water-soluble sulfate. High levels of calcium and sulfate occurred for horizons above the water table. This accumulation is attributed to groundwater bearing these ions and subsequently discharging them to the overlying soil. Dead citrus roots appear to act as wicks to aid water transfer from lower to higher horizons. The roots and their empty channels provide spaces in which the gypsum can precipitate if the concentrations of calcium and sulfate in the evaporating groundwater exceed the solubility product of gypsum.

Syslo, S.K.; Myhre, D.L.; Harris, W.G.

1988-02-01

243

Mineralisation of reconstituted collagen using polyvinylphosphonic acid/polyacrylic acid templating matrix protein analogues in the presence of calcium, phosphate and hydroxyl ions  

PubMed Central

The complex morphologies of mineralised collagen fibrils are regulated through interactions between the collagen matrix and non-collagenous extracellular proteins. In the present study, polyvinylphosphonic acid, a biomimetic analogue of matrix phosphoproteins, was synthesised and confirmed with FTIR and NMR. Biomimetic mineralisation of reconstituted collagen fibrils devoid of natural non-collagenous proteins was demonstrated with TEM using a Portland cement-containing resin composite and a phosphate-containing fluid in the presence of polyacrylic acid as sequestration, and polyvinylphosphonic acid as templating matrix protein analogues. In the presence of these dual biomimetic analogues in the mineralisation medium, intrafibrillar and extrafibrillar mineralisation via bottom-up nanoparticle assembly based on the nonclassical crystallisation pathway could be identified. Conversely, only large mineral spheres with no preferred association with collagen fibrils were observed in the absence of biomimetic analogues in the medium. Mineral phases were evident within the collagen fibrils as early as 4 hours after the initially-formed amorphous calcium phosphate nanoprecursors were transformed into apatite nanocrystals. Selected area electron diffraction patterns of highly mineralised collagen fibrils were nearly identical to those of natural bone, with apatite crystallites preferentially aligned along the collagen fibril axes. PMID:20621767

Kim, Young Kyung; Gu, Li-sha; Bryan, Thomas E.; Kim, Jong Ryul; Chen, Liang; Liu, Yan; Yoon, James C.; Breschi, Lorenzo; Pashley, David H.; Tay, Franklin R.

2010-01-01

244

The Role of n-3 Polyunsaturated Fatty Acids in the Prevention and Treatment of Breast Cancer  

PubMed Central

Breast cancer (BC) is the most common cancer among women worldwide. Dietary fatty acids, especially n-3 polyunsaturated fatty acids (PUFA), are believed to play a role in reducing BC risk. Evidence has shown that fish consumption or intake of long-chain n-3 PUFA, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are beneficial for inhibiting mammary carcinogenesis. The evidence regarding ?-linolenic acid (ALA), however, remains equivocal. It is essential to clarify the relation between ALA and cancer since ALA is the principal source of n-3 PUFA in the Western diet and the conversion of ALA to EPA and DHA is not efficient in humans. In addition, the specific anticancer roles of individual n-3 PUFA, alone, have not yet been identified. Therefore, the present review evaluates ALA, EPA and DHA consumed individually as well as in n-3 PUFA mixtures. Also, their role in the prevention of BC and potential anticancer mechanisms of action are examined. Overall, this review suggests that each n-3 PUFA has promising anticancer effects and warrants further research. PMID:25412153

Liu, Jiajie; Ma, David W. L.

2014-01-01

245

Nutritional interventions to prevent and treat osteoarthritis. Part I: focus on fatty acids and macronutrients.  

PubMed

Osteoarthritis (OA) is the most common cause of musculoskeletal disability in elderly individuals, and it places an enormous economic burden on society. Management of OA is primarily focused on palliative relief by using agents such as nonsteroidal anti-inflammatory drugs and analgesics. However, such an approach is limited by a narrow therapeutic focus that fails to address the progressive and multimodal nature of OA. Given the favorable safety profile of most nutritional interventions, identifying disease-modifying nutritional agents capable of improving symptoms and also preventing, slowing, or even reversing the degenerative process in OA should remain an important paradigm in translational and clinical research. Applying advances in nutritional science to musculoskeletal medicine remains challenging, given the fluid and dynamic nature of the field, along with a rapidly developing regulatory climate over manufacturing and commerce requirements. The aim of this article is to review the available literature on effectiveness and potential mechanism of macronutrients for OA, with a focus on the following: long-chain ?-3 essential fatty acids eicosapentaenoic acid and docosahexaenoic acid, functional ?-6 fatty acid ?-linolenic acid, and macronutrient composition of background diet. There also is a discussion about the concept of rational polysupplementation via the strategic integration of multiple nutraceuticals with potential complementary mechanisms for improving outcomes in OA. As applied nutritional science evolves, it will be important to stay on the forefront of proteomics, metabolomics, epigenetics, and nutrigenomics, because they hold enormous potential for developing novel therapeutic and prognostic breakthroughs in many areas of medicine, including OA. PMID:22632694

Lopez, Hector L

2012-05-01

246

Role of intracellular calcium and NADPH oxidase NOX5-S in acid-induced DNA damage in Barrett's cells and Barrett's esophageal adenocarcinoma cells.  

PubMed

Mechanisms whereby acid reflux may accelerate the progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EA) are not fully understood. Acid and reactive oxygen species (ROS) have been reported to cause DNA damage in Barrett's cells. We have previously shown that NADPH oxidase NOX5-S is responsible for acid-induced H2O2 production in Barrett's cells and in EA cells. In this study we examined the role of intracellular calcium and NADPH oxidase NOX5-S in acid-induced DNA damage in a Barrett's EA cell line FLO and a Barrett's cell line CP-A. We found that pulsed acid treatment significantly increased tail moment in FLO and CP-A cells and histone H2AX phosphorylation in FLO cells. In addition, acid treatment significantly increased intracellular Ca(2+) in FLO cells, an increase that is blocked by Ca(2+)-free medium with EGTA and thapsigargin. Acid-induced increase in tail moment was significantly decreased by NADPH oxidase inhibitor diphenylene iodonium in FLO cells, and by blockade of intracellular Ca(2+) increase or knockdown of NOX5-S with NOX5 small-interfering RNA (siRNA) in FLO and CP-A cells. Acid-induced increase in histone H2AX phosphorylation was significantly decreased by NOX5 siRNA in FLO cells. Conversely, overexpression of NOX5-S significantly increased tail moment and histone H2AX phosphorylation in FLO cells. We conclude that pulsed acid treatment causes DNA damage via increase of intracellular calcium and activation of NOX5-S. It is possible that in BE acid reflux increases intracellular calcium, activates NOX5-S, and increases ROS production, which causes DNA damage, thereby contributing to the progression from BE to EA. PMID:24699332

Li, Dan; Cao, Weibiao

2014-05-15

247

Vasodilation by in vivo activation of astrocyte endfeet via two-photon calcium uncaging as a strategy to prevent brain ischemia  

NASA Astrophysics Data System (ADS)

Decreased cerebral blood flow causes brain ischemia and plays an important role in the pathophysiology of many neurodegenerative diseases, including Alzheimer's disease and vascular dementia. In this study, we photomodulated astrocytes in the live animal by a combination of two-photon calcium uncaging in the astrocyte endfoot and in vivo imaging of neurovasculature and astrocytes by intravital two-photon microscopy after labeling with cell type specific fluorescent dyes. Our study demonstrates that photomodulation at the endfoot of a single astrocyte led to a 25% increase in the diameter of a neighboring arteriole, which is a crucial factor regulating cerebral microcirculation in downstream capillaries. Two-photon uncaging in the astrocyte soma or endfoot near veins does not show the same effect on microcirculation. These experimental results suggest that infrared photomodulation on astrocyte endfeet may be a strategy to increase cerebral local microcirculation and thus prevent brain ischemia.

Chen, Yuanxin; Mancuso, James; Zhao, Zhen; Li, Xuping; Cheng, Jie; Roman, Gustavo; Wong, Stephen T. C.

2013-12-01

248

Effect of Acidic Environment on the Push-Out Bond Strength of Calcium-Enriched Mixture Cement  

PubMed Central

Introduction: This laboratory study was performed to evaluate the effect of different acidic pH values on the push-out bond strength of calcium-enriched mixture (CEM) cement. Methods and Materials: Forty-eight root dentin slices were obtained from freshly extracted single rooted human teeth and their lumen were instrumented to achieve a diameter of 1.3 mm. Then, CEM cement was mixed according to manufacturers’ instruction and placed in the lumens with minimal pressure. The specimens were randomly divided into four groups (n=12) which were wrapped in pieces of gauze soaked in either synthetic tissue fluid (STF) (pH=7.4) or butyric acid which was buffered at pH values of 4.4, 5.4 and 6.4. They were then incubated for 4 days at 37°C. The push-out test was performed by means of the universal testing machine. Specimens were then examined under a digital light microscope at 20× magnification to determine the nature of the bond failure. The data were analyzed using the Kruskal-Wallis test followed by Dunn’s test for pairwise comparisons. Results: The highest push-out bond strength (10.19±4.39) was seen in the pH level of 6.4, which was significantly different from the other groups (P<0.05). The values decreased to 2.42±2.25 MPa after exposure to pH value of 4.4. Conclusion: Lower pH value of highly acidic environments (pH=4.4), adversely affects the force needed for displacement of CEM cement; while in higher pH values (pH=6.4) the bond-strength was not affected. CEM cement is recommended in clinical situations where exposure to acidic environment is unavoidable. PMID:25386207

Sobhnamayan, Fereshte; Sahebi, Safoora; Naderi, Misagh; Shojaee, Nooshin Sadat; Shanbezadeh, Najmeh

2014-01-01

249

The Effect of Acidic pH on Microleakage of Mineral Trioxide Aggregate and Calcium-Enriched Mixture Apical Plugs  

PubMed Central

Introduction: The purpose of this laboratory study was to evaluate the effect of acidic pH on the sealing ability of calcium-enriched mixture (CEM) cement and mineral trioxide aggregate (MTA) apical plugs. Methods and Materials: Seventy single-rooted human maxillary anterior teeth were recruited. The teeth were randomly divided into 4 experimental groups (n=15), and 1 negative and 1 positive control groups of 5. The root canals were cleaned and shaped and the terminal 3 mm of the roots were resected. Then MTA and CEM cement plugs were condensed in apical region with 3 mm thicknesses. The samples were exposed to pH values of 5.5 and 7.4. Leakage was evaluated by the fluid filtration technique at 1, 7, 14, 30 day intervals. Data were analyzed by the repeated measures MANOVA, one-way ANOVA and MANOVA/Bonferroni test. Results: Acidic pH significantly reduced the sealing ability of MTA after 1, 14 and 30 days (P<0.05). The rate of microleakage in CEM cement samples in acidic pH was significantly greater than that in neutral pH in day 30 (P<0.05). There was no significant difference between the sealing property of MTA and CEM cement at both pH levels (P>0.05). Conclusion: It can be concluded that the CEM cement exhibited similar sealing ability as MTA at both pH levels. In addition, an acidic pH environment reduced the sealing ability of MTA and CEM cement after 30 days. PMID:25386205

Mirhadi, Hossein; Moazzami, Fariborz; Safarzade, Sareh

2014-01-01

250

Effects of calcium on seed germination, seedling growth and photosynthesis of six forest tree species under simulated acid rain.  

PubMed

We selected six tree species, Pinus massoniana Lamb., Cryptomeria fortunei Hooibr. ex Otto et Dietr., Cunninghamia lanceolata (Lamb.) Hook., Liquidambar formosana Hance, Pinus armandii Franch. and Castanopsis chinensis Hance, which are widely distributed as dominant species in the forest of southern China where acid deposition is becoming more and more serious in recent years. We investigated the effects and potential interactions between simulated acid rain (SiAR) and three calcium (Ca) levels on seed germination, radicle length, seedling growth, chlorophyll content, photosynthesis and Ca content in leaves of these six species. We found that the six species showed different responses to SiAR and different Ca levels. Pinus armandii and C. chinensis were very tolerant to SiAR, whereas the others were more sensitive. The results of significant SiAR?×?Ca interactions on different physiological parameters of the six species demonstrate that additional Ca had a dramatic rescue effect on the seed germination and seedling growth for the sensitive species under SiAR. Altogether, we conclude that the negative effects of SiAR on seed germination, seedling growth and photosynthesis of the four sensitive species could be ameliorated by Ca addition. In contrast, the physiological processes of the two tolerant species were much less affected by both SiAR and Ca treatments. This conclusion implies that the degree of forest decline caused by long-term acid deposition may be attributed not only to the sensitivity of tree species to acid deposition, but also to the Ca level in the soil. PMID:21470980

Liu, Ting-Wu; Wu, Fei-Hua; Wang, Wen-Hua; Chen, Juan; Li, Zhen-Ji; Dong, Xue-Jun; Patton, Janet; Pei, Zhen-Ming; Zheng, Hai-Lei

2011-04-01

251

4-Phenylbutyric acid prevent cytotoxicity induced by thapsigargin in rat cardiac fibroblast.  

PubMed

Cardiac fibroblast (CF) survival is important for the maintenance of the extracellular matrix homeostasis in the heart; providing a functional support to cardiomyocytes necessary for the correct myocardial function. Endoplasmic reticulum (ER) stress causes cellular dysfunction and cell death by apoptosis; and thapsigargin is a well-known ER stress inducer. On the other hand, the chemical chaperone, 4-phenylbutyric acid (4-PBA) had showed to prevent ER stress; however, in cardiac fibroblast both the ER stress induced by thapsigargin and prevention by 4-PBA, have not been studied in detail. Neonate rat CF were treated with thapsigargin in presence or absence of 4-PBA, and cell viability was evaluated by trypan blue exclusion and apoptosis by flow cytometry; whereas CHOP, BIP, PDI, ATF4 and procollagen protein levels were assessed by western blot. In CF, thapsigargin triggered the unfolded protein response detected by early increases in ATF4, CHOP, PDI and BIP protein levels as well as, the accumulation of intracellular procollagen. Thapsigargin also stimulated CF death in a time and concentration-dependent manner. ER stress, CF death and apoptosis induced by thapsigargin were prevented by 4-PBA. Conclusion our data suggest that 4-PBA prevent ER stress, intracellular procollagen accumulation, CF death and apoptosis induced by thapsigargin. PMID:25149584

Humeres, C; Montenegro, J; Varela, M; Ayala, P; Vivar, R; Letelier, A; Olmedo, I; Catalán, M; Rivas, C; Baeza, P; Muñoz, C; García, L; Lavandero, S; Díaz-Araya, G

2014-12-01

252

Hyaluronic acid prevents immunosuppressive drug-induced ovarian damage via up-regulating PGRMC1 expression  

PubMed Central

Chemotherapy treatment in women can frequently cause damage to the ovaries, which may lead to primary ovarian insufficiency (POI). In this study, we assessed the preventative effects of hyaluronic acid (HA) in immunosuppressive drug-induced POI-like rat models and investigated the possible mechanisms. We found that HA, which was reduced in primary and immunosuppressant-induced POI patients, could protect the immunosuppressant-induced damage to granulosa cells (GCs) in vitro. Then we found that HA blocked the tripterygium glycosides (TG) induced POI-like presentations in rats, including delayed or irregular estrous cycles, reduced 17 beta-estradiol(E2) concentration, decreased number of follicles, destruction of follicle structure, and damage of reproductive ability. Furthermore, we investigated the mechanisms of HA prevention effects on POI, which was associated with promotion of GC proliferation and PGRMC1 expression. In conclusion, HA prevents chemotherapy-induced ovarian damage by promoting PGRMC1 in GCs. This study may provide a new strategy for prevention and treatment of POI. PMID:25558795

Zhao, Guangfeng; Yan, Guijun; Cheng, Jie; Zhou, Xue; Fang, Ting; Sun, Haixiang; Hou, Yayi; Hu, Yali

2015-01-01

253

Hyaluronic acid prevents immunosuppressive drug-induced ovarian damage via up-regulating PGRMC1 expression.  

PubMed

Chemotherapy treatment in women can frequently cause damage to the ovaries, which may lead to primary ovarian insufficiency (POI). In this study, we assessed the preventative effects of hyaluronic acid (HA) in immunosuppressive drug-induced POI-like rat models and investigated the possible mechanisms. We found that HA, which was reduced in primary and immunosuppressant-induced POI patients, could protect the immunosuppressant-induced damage to granulosa cells (GCs) in vitro. Then we found that HA blocked the tripterygium glycosides (TG) induced POI-like presentations in rats, including delayed or irregular estrous cycles, reduced 17 beta-estradiol(E2) concentration, decreased number of follicles, destruction of follicle structure, and damage of reproductive ability. Furthermore, we investigated the mechanisms of HA prevention effects on POI, which was associated with promotion of GC proliferation and PGRMC1 expression. In conclusion, HA prevents chemotherapy-induced ovarian damage by promoting PGRMC1 in GCs. This study may provide a new strategy for prevention and treatment of POI. PMID:25558795

Zhao, Guangfeng; Yan, Guijun; Cheng, Jie; Zhou, Xue; Fang, Ting; Sun, Haixiang; Hou, Yayi; Hu, Yali

2015-01-01

254

Omega-3 fatty acid is a potential preventive agent for recurrent colon cancer.  

PubMed

Increasing evidence supports the contention that many malignancies, including sporadic colorectal cancer, are driven by the self-renewing, chemotherapy-resistant cancer stem/stem-like cells (CSC/CSLC), underscoring the need for improved preventive and therapeutic strategies targeting CSCs/CSLCs. Omega-3 polyunsaturated fatty acids (?-3 PUFA), have been reported to inhibit the growth of primary tumors, but their potential as a preventive agent for recurring cancers is unexplored. The primary objectives of this investigation are (i) to examine whether eicosapentaenoic acid (EPA; one of the ?-3 PUFA) synergizes with FuOx (5-FU+Oxaliplatin), the backbone of colon cancer chemotherapy, and (ii) whether EPA by itself or in combination with conventional chemotherapy prevents the recurrence of colon cancer via eliminating/suppressing CSCs/CSLCs. FuOx-resistant (chemoresistant; CR) colon cancer cells, highly enriched in CSCs, were used for this study. Although EPA alone was effective, combination of EPA and FuOx was more potent in (i) inhibiting cell growth, colonosphere formation, and sphere-forming frequency, (ii) increasing sphere disintegration, (iii) suppressing the growth of SCID mice xenografts of CR colon cancer cells, and (iv) decreasing proinflammatory metabolites in mice. In addition, EPA + FuOx caused a reduction in CSC/CSLC population. The growth reduction by this regimen is the result of increased apoptosis as evidenced by PARP cleavage. Furthermore, increased pPTEN, decreased pAkt, normalization of ?-catenin expression, localization, and transcriptional activity by EPA suggests a role for the PTEN-Akt axis and Wnt signaling in regulating this process. Our data suggest that EPA by itself or in combination with FuOx could be an effective preventive strategy for recurring colorectal cancer. PMID:25193342

Vasudevan, Anita; Yu, Yingjie; Banerjee, Sanjeev; Woods, James; Farhana, Lulu; Rajendra, Sindhu G; Patel, Aamil; Dyson, Gregory; Levi, Edi; Maddipati, Krishna Rao; Majumdar, Adhip P N; Nangia-Makker, Pratima

2014-11-01

255

Effects of the N/L-type calcium channel blocker cilnidipine on nephropathy and uric acid metabolism in hypertensive patients with chronic kidney disease (J-CIRCLE study).  

PubMed

This study assessed the urinary albumin/creatinine ratio (ACR) and uric acid metabolism in 70 hypertensive patients with chronic kidney disease in whom urinary ACR had remained ?30 mg/g under the treatment of the L-type calcium channel blocker amlodipine. Three months after switching to the N/L-type calcium channel blocker cilnidipine, blood pressure (BP) did not change; however, urinary ACR significantly decreased with cilnidipine. Serum uric acid levels showed no significant change. In cases where uric acid production had been high (urinary uric acid/creatinine ratio ?0.5), the urinary uric acid/creatinine ratio decreased significantly after cilnidipine treatment, suggesting that cilnidipine can suppress excessive uric acid formation. These results suggest that switching from amlodipine to cilnidipine results in a significant reduction in urinary ACR as well as significant reduction in uric acid production. Thus, cilnidipine is more useful than amlodipine in improving albuminuria and uric acid metabolism in hypertensive patients with chronic kidney disease. PMID:25264215

Uchida, Shunya; Takahashi, Masato; Sugawara, Masahiro; Saito, Tomoaki; Nakai, Kazuhiko; Fujita, Masami; Mochizuki, Koichi; Shin, Isu; Morita, Takashi; Hikita, Tomoyuki; Itakura, Hironao; Takahashi, Yuko; Mizuno, Shigeki; Ohno, Yasumi; Ito, Kageki; Ito, Takafumi; Soma, Masayoshi

2014-10-01

256

Prevention of bone mineral changes induced by bed rest: Modification by static compression simulating weight bearing, combined supplementation of oral calcium and phosphate, calcitonin injections, oscillating compression, the oral diophosphonatedisodium etidronate, and lower body negative pressure  

NASA Technical Reports Server (NTRS)

The phenomenon of calcium loss during bed rest was found to be analogous to the loss of bone material which occurs in the hypogravic environment of space flight. Ways of preventing this occurrence are investigated. A group of healthy adult males underwent 24-30 weeks of continuous bed rest. Some of them were given an exercise program designed to resemble normal ambulatory activity; another subgroup was fed supplemental potassium phosphate. The results from a 12-week period of treatment were compared with those untreated bed rest periods. The potassium phosphate supplements prevented the hypercalciuria of bed rest, but fecal calcium tended to increase. The exercise program did not diminish the negative calcium balance. Neither treatment affected the heavy loss of mineral from the calcaneus. Several additional studies are developed to examine the problem further.

Schneider, V. S.; Hulley, S. B.; Donaldson, C. L.; Vogel, J. M.; Rosen, S. N.; Hantman, D. A.; Lockwood, D. R.; Seid, D.; Hyatt, K. H.; Jacobson, L. B.

1974-01-01

257

Crystal size distributions of induced calcium carbonate crystals in polyaspartic acid and Mytilus edulis acidic organic proteins aqueous solutions  

NASA Astrophysics Data System (ADS)

Different concentrations of soluble matrix extracts from Mytilus edulis and polyaspartic acid were mixed with CaCl 2 aqueous solutions to produce CaCO 3 crystallizations under controlled conditions. The obtained crystals were observed at several intervals of time by optical microscopy and scanning electron microscopy (SEM). Image treatment of the SEM images allowed quantifying the crystal size distribution (CSD) in different crystallization conditions. CSD graphics showed that polyaspartic acid induced nucleation and inhibited crystal growth, and soluble matrix extracts from Mytilus edulis induced nucleation, but its inhibition rate of crystal growth is less than polyaspartic. Soluble matrix extracts from Mytilus edulis showed an equilibrium between nucleation and crystal growth. Also, XRD patterns have been acquired in order to determine the crystalline phases obtained by inducing crystallization (calcite and vaterite). Vaterite polymorph appeared in all induced crystallization events, but not in blank aqueous solutions.

Roqué, Josep; Molera, Judit; Vendrell-Saz, Màrius; Salvadó, Nativitat

2004-02-01

258

Controlled release of gentamicin from calcium phosphate—poly(lactic acid- co-glycolic acid) composite bone cement  

Microsoft Academic Search

Modification of a self setting bone cement with biodegradable microspheres to achieve controlled local release of antibiotics without compromising mechanical properties was investigated. Different biodegradable microsphere batches were prepared from poly(lactic-co-glycolic acid) (PLGA) using a spray-drying technique to encapsulate gentamicin crobefate varying PLGA composition and drug loading. Microsphere properties such as surface morphology, particle size and antibiotic drug release profiles

Julia Schnieders; Uwe Gbureck; Roger Thull; Thomas Kissel

2006-01-01

259

Intravenous ascorbic acid to prevent and treat cancer-associated sepsis?  

PubMed Central

The history of ascorbic acid (AA) and cancer has been marked with controversy. Clinical studies evaluating AA in cancer outcome continue to the present day. However, the wealth of data suggesting that AA may be highly beneficial in addressing cancer-associated inflammation, particularly progression to systemic inflammatory response syndrome (SIRS) and multi organ failure (MOF), has been largely overlooked. Patients with advanced cancer are generally deficient in AA. Once these patients develop septic symptoms, a further decrease in ascorbic acid levels occurs. Given the known role of ascorbate in: a) maintaining endothelial and suppression of inflammatory markers; b) protection from sepsis in animal models; and c) direct antineoplastic effects, we propose the use of ascorbate as an adjuvant to existing modalities in the treatment and prevention of cancer-associated sepsis. PMID:21375761

2011-01-01

260

Dietary Pantothenic Acid Requirement of Fingerling Channel Catfish1  

Microsoft Academic Search

Two experiments were conducted to reevaluate the dietary panto- thenic acid requirement for fingerling channel catfish. Purified diets supplemented with calcium d-pantothenate were used in both experiments. The results indicate that the previously reported requirement value was underestimated. The minimum dietary calcium d-pantothenate level that produced maximum growth, feed efficiency and prevented the characteristic deficiency sign of gill lesions was

ROBERT P. WILSON; PAUL R. BOWSER; ANDWILLIAM E. POE

261

Acidosis and hypercalciuria: renal mechanisms affecting calcium, magnesium and sodium excretion in the sheep.  

PubMed

1. Observations were made on the excretion of calcium and magnesium by the sheep's kidney following manipulation of the acid-base status.2. Intravascular administration of a synthetic solution resembling saliva abolished the naturally occurring acidosis in sheep during feeding, and it also prevented the normal onset of post-prandial hypercalciuria and hypermagnesiuria.3. Non-respiratory acidosis (induced by infusion of hydrochloric acid) and respiratory acidosis arising from inhalation of 6% (v/v) CO(2) in air both caused an acute increase in calcium excretion.4. Measurement of filtered loads showed that feeding exerted an effect on the functional characteristics of the sheep's kidney. The renal clearances of calcium and magnesium increased, whereas sodium clearance decreased.5. Experimental conditions were arranged so that variations in acid-base status could be imposed at a time when the filtered load of calcium was declining.6. With hydrochloric acid-acidosis the renal excretion of calcium increased, despite a steady fall in the filtered load. With sodium bicarbonate alkalosis, the filtered load and the renal excretion of calcium decreased in unison.7. These variations in calcium excretion were not accompanied by corresponding changes in the excretion of sodium.8. It is concluded that the renal tubules in the sheep are sensitive to acid-base status and that they respond to a lowering of the blood pH by decreasing the tubular reabsorption of filtered calcium. PMID:5499811

Stacy, B D; Wilson, B W

1970-10-01

262

Effect of different amounts and types of calcium on colonic cell proliferation and fecal bile acids concentration  

E-print Network

in rats fed the high butter fat diet. Eight-four male Sprague Dawley rats were randomly assigned to 7 treatment groups with 12-13 rats per group. One group received 5% butter and 0. 5% calcium (from calcium phosphate) and served as control group. Rats...). They served as experiment 2 -- types of calcium treatment groups. In experiment 1, when rats received increasing amount of calcium, their fecal output and fecal lipids increased proportionally. Rats received 1. 5% calcium in the high fat diet resulted...

C?hen Hsiao-Ch?ing

1991-01-01

263

Docosahexaenoic acid prevents palmitate-induced activation of proteolytic systems in C2C12 myotubes.  

PubMed

Saturated fatty acids like palmitate contribute to muscle atrophy in a number of conditions (e.g., type II diabetes) by altering insulin signaling. Akt is a key modulator of protein balance that inhibits the FoxO transcription factors (e.g., FoxO3) which selectively induce the expression of atrophy-inducing genes (atrogenes) in the ubiquitin-proteasome and autophagy-lysosome systems. Conversely, omega-3 polyunsaturated fatty acids have beneficial effects on insulin signaling and may preserve muscle mass. In an earlier report, the omega-3 fatty acid docosahexaenoic acid (DHA) protected myotubes from palmitate-induced atrophy; the mechanisms underlying the alterations in protein metabolism were not identified. This study investigated whether DHA prevents a palmitate-induced increase in proteolysis by restoring Akt/FoxO signaling. Palmitate increased the rate of protein degradation, while cotreatment with DHA prevented the response. Palmitate reduced the activation state of Akt and increased nuclear FoxO3 protein while decreasing its cytosolic level. Palmitate also increased the messenger RNAs (mRNAs) of two FoxO3 atrogene targets, the E3 ubiquitin ligase atrogin-1/MAFbx and the autophagy mediator Bnip3. DHA attenuated the effects of palmitate on Akt activation, FoxO3 localization and atrogene mRNAs. DHA, alone or in combination with palmitate and decreased the ratio of LC3B-II:LC3B-I protein as well as the rate of autophagosome formation, as indicated by reduced LC3B-II protein in the presence of 10 mmol/L methylamine, suggesting an independent effect of DHA on the macroautophagy pathway. These data indicate that palmitate induces myotube atrophy, at least in part, by activating multiple proteolytic systems and that DHA counters the catabolic effects of palmitate by restoring Akt/FoxO signaling. PMID:24835079

Woodworth-Hobbs, Myra E; Hudson, Matthew B; Rahnert, Jill A; Zheng, Bin; Franch, Harold A; Price, S Russ

2014-08-01

264

THE POTENTIAL ROLE OF DIETARY OMEGA 3 FATTY ACIDS IN THE PREVENTION OF DEMENTIA AND MACULAR DEGENERATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Dementia and AMD are major causes of disability in the elderly. Omega-3 fatty acids, particularly docosahexaenoic acid (DHA) are highly concentrated in brain and retinal tissue and have been implicated in the prevention or delay in progression of dementia and age-related macular degeneration (AMD). ...

265

ALUMINUM SOLUBILITY, CALCIUM-ALUMINUM EXCHANGE, AND PH IN ACID FOREST SOILS  

EPA Science Inventory

Important components in several models designed to describe the effects of acid deposition on soils and surface waters are the pH-A1 and Ca-A1 exchange relationships. f A1 solubility is controlled by A1 trihydroxide minerals, the theoretical pH-A1 relationship can be described by...

266

Safety assessment of (?)-hydroxycitric acid and Super CitriMax ®, a novel calcium\\/potassium salt  

Microsoft Academic Search

(?)-Hydroxycitric acid (HCA) is a principle constituent (10–30%) of the dried fruit rind of Garcinia cambogia, a plant native to Southeastern Asia. The dried rind has been used for centuries throughout Southeast Asia as a food preservative, flavoring agent and carminative. Extensive experimental studies show that HCA inhibits fat synthesis and reduces food intake. The objective of this review is

M. G. Soni; G. A. Burdock; H. G. Preuss; S. J. Stohs; S. E. Ohia; D. Bagchi

2004-01-01

267

Bioefficacy of a novel calcium–potassium salt of (?)-hydroxycitric acid  

Microsoft Academic Search

Obesity is associated with cardiovascular disease, diabetes and certain forms of cancer. Popular strategies on weight loss often fail to address many key factors such as fat mass, muscle density, bone density, water mass, their inter-relationships and impact on energy production, body composition, and overall health and well-being. (?)-Hydroxycitric acid (HCA), a natural plant extract from the dried fruit rind

Bernard W. Downs; Manashi Bagchi; Gottumukkala V. Subbaraju; Michael A. Shara; Harry G. Preuss; Debasis Bagchi

2005-01-01

268

Increased tissue levels of omega-3 polyunsaturated fatty acids prevents pathological preterm birth  

PubMed Central

Omega-3 polyunsaturated fatty acids such as eicosapentaenoic acid (EPA) have anti-inflammatory effects. Preterm birth is an important problem in modern obstetrics and one of the main causes is an inflammation. We here showed that abundance of omega-3 fatty acids reduced the incidence of preterm birth induced by LPS with fat-1 mice, capable of converting omega-6 to omega-3 fatty acids. We also indicated that the gene expression of IL-6 and IL-1? in uteruses and the number of cervical infiltrating macrophages were reduced in fat-1 mice. The analyses of lipid metabolomics showed the high level of 18-hydroxyeicosapentaenoate in fat-1 mice, which was derived from EPA and was metabolized to anti-inflammatory product named resolvin E3 (RvE3). We finally showed that the administration of RvE3 to LPS-exposed pregnant wild type mice lowered the incidence of preterm birth. Our data suggest that RvE3 could be a potential new therapeutic for the prevention of preterm birth. PMID:24177907

Yamashita, Aki; Kawana, Kei; Tomio, Kensuke; Taguchi, Ayumi; Isobe, Yosuke; Iwamoto, Ryo; Masuda, Koji; Furuya, Hitomi; Nagamatsu, Takeshi; Nagasaka, Kazunori; Arimoto, Takahide; Oda, Katsutoshi; Wada-Hiraike, Osamu; Yamashita, Takahiro; Taketani, Yuji; Kang, Jing X.; Kozuma, Shiro; Arai, Hiroyuki; Arita, Makoto; Osuga, Yutaka; Fujii, Tomoyuki

2013-01-01

269

Soil calcium status and the response of stream chemistry to changing acidic deposition rates  

USGS Publications Warehouse

Despite a decreasing trend in acidic deposition rates over the past two to three decades, acidified surface waters in the northeastern United States have shown minimal changes. Depletion of soil Ca pools has been suggested as a cause, although changes in soil Ca pools have not been directly related to long-term records of stream chemistry. To investigate this problem, a comprehensive watershed study was conducted in the Neversink River Basin, in the Catskill Mountains of New York, during 1991-1996. Spatial variations of atmospheric deposition, soil chemistry, and stream chemistry were evaluated over an elevation range of 817-1234 m to determine whether these factors exhibited elevational patterns. An increase in atmospheric deposition of SO4 with increasing elevation corresponded with upslope decreases of exchangeable soil base concentrations and acid-neutralizing capacity of stream water. Exchangeable base concentrations in homogeneous soil incubated within the soil profile for one year also decreased with increasing elevation. An elevational gradient in precipitation was not observed, and effects of a temperature gradient on soil properties were not detected. Laboratory leaching experiments with soils from this watershed showed that (1) concentrations of Ca in leachate increased as the concentrations of acid anions in added solution increased, and (2) the slope of this relationship was positively correlated with base saturation. Field and laboratory soil analyses are consistent with the interpretation that decreasing trends in acid-neutralizing capacity in stream water in the Neversink Basin, dating back to 1984, are the result of decreases in soil base saturation caused by acidic deposition.

Lawrence, G.B.; David, M.B.; Lovett, G.M.; Murdoch, P.S.; Burns, D.A.; Stoddard, J.L.; Baldigo, B.P.; Porter, J.H.; Thompson, A.W.

1999-01-01

270

Study on the solubility and morphology of calcium sulfate dihydrate in nitric acid and phosphoric acid aqueous medium  

Microsoft Academic Search

In order to investigate the solubility of CaSO4·2H2O at different contents of H3PO4 and HNO3 aqueous medium, a series of tests was designed for determining the solubility of CaSO4·2H2O at 25°C and 65°C in different acidic concentration solvents, the crystal morphology of the deposition solid-phase after liquid-solid equilibrium was examined by microscope, and the crystalline of the deposition solid-phase was

Xiaoxia Zheng; Hongjian Jing; Junqiang Feng; Caimei Fan; Guangyue Ding; Yunfang Wang

2010-01-01

271

The effect of casein phosphopeptide-amorphous calcium phosphate paste and sodium fluoride mouthwash on the prevention of dentine erosion: An in vitro study  

PubMed Central

Aim: The purpose was to compare the effect of 0.2% sodium fluoride mouthwash and casein phosphopeptide-amorphous calcium phosphate paste on prevention of dentin erosion. Materials and Methods: Buccal surfaces of 36 sound premolar teeth were ground flat and polished with abrasive discs. Half the polished surfaces were covered with tape to maintain a reference surface. Samples were randomly allocated into three groups. Group A was pretreated with tooth mousse (TM) 4 times a day for 5 days. Group B was pretreated with 0.2% sodium fluoride mouthwash 4 times a day for 5 days. Group C was considered as the control group with no pretreatment. In the next step, the samples were exposed to Coca-Cola 4 times a day for 3 days. After each erosive cycle, the samples were rinsed with deionized water and stored in artificial saliva. The surface loss was determined using profilometry. Results: The erosion in both Groups A and B was less than the control group. The surface loss in mouthwash group was significantly lower than in the control group. Erosion in TM group was more than the mouthwash group and less than the control group. Conclusion: Sodium fluoride mouthwash is more effective for prevention of dentin erosion. PMID:24944448

Moezizadeh, Maryam; Alimi, Azar

2014-01-01

272

Initial Amino Acid Intake Influences Phosphorus and Calcium Homeostasis in Preterm Infants – It Is Time to Change the Composition of the Early Parenteral Nutrition  

PubMed Central

Background Early aggressive parenteral nutrition (PN), consisting of caloric and nitrogen intake soon after birth, is currently proposed for the premature baby. Some electrolyte disturbances, such as hypophosphatemia and hypercalcemia, considered unusual in early life, were recently described while using this PN approach. We hypothesize that, due to its impact on cell metabolism, the initial amino acid (AA) amount may specifically influence the metabolism of phosphorus, and consequently of calcium. We aim to evaluate the influence of AA intake on calcium-phosphorus metabolism, and to create a calculation tool to estimate phosphorus needs. Methods Prospective observational study. Phosphate and calcium plasma concentrations and calcium balance were evaluated daily during the first week of life in very preterm infants, and their relationship with nutrition was studied. For this purpose, infants were divided into three groups: high, medium and low AA intake (HAA, MAA, LAA). A calculation formula to assess phosphorus needs was elaborated, with a theoretical model based on AA and calcium intake, and the cumulative deficit of phosphate intake was estimated. Results 154 infants were included. Hypophosphatemia (12.5%) and hypercalcemia (9.8%) were more frequent in the HAA than in the MAA (4.6% and 4.8%) and in the LAA group (0% and 1.9%); both p<0.001. Discussion Calcium-phosphorus homeostasis was influenced by the early AA intake. We propose to consider phosphorus and calcium imbalances as being part of a syndrome, related to incomplete provision of nutrients after the abrupt discontinuation of the placental nutrition at birth (PI-ReFeeding syndrome). We provide a simple tool to calculate the optimal phosphate intake. The early introduction of AA in the PN soon after birth might be completed by an early intake of phosphorus, since AA and phosphorus are (along with potassium) the main determinants of cellular growth. PMID:23977367

Bonsante, Francesco; Iacobelli, Silvia; Latorre, Giuseppe; Rigo, Jacques; De Felice, Claudio; Robillard, Pierre Yves; Gouyon, Jean Bernard

2013-01-01

273

Tauroursodeoxycholic acid inhibits experimental colitis by preventing early intestinal epithelial cell death.  

PubMed

Ulcerative colitis (UC) is characterized by increased epithelial cell death and subsequent breakdown of the intestinal epithelial barrier, which perpetuates chronic intestinal inflammation. Since fecal bile acid dysmetabolism is associated with UC and tauroursodeoxycholic acid (TUDCA) has been shown to improve murine colitis, we evaluated the effect of TUDCA on intestinal epithelial cell death in a mouse model of UC-like barrier dysfunction elicited by dextran sulfate sodium (DSS). We identified the prevention of colonic caspase-3 induction, a key proapoptotic marker which was also over-activated in UC, as the earliest event resulting in a clear clinical benefit. Whereas vehicle-treated mice showed a cumulative mortality of 40%, all TUDCA-treated mice survived the DSS experiment during a 14-day follow-up period. In line with a barrier protective effect, TUDCA decreased bacterial translocation to the spleen and stimulated mucin production. Similarly, TUDCA inhibited lipopolysaccharide-induced intestinal permeability and associated enterocyte apoptosis. The anti-apoptotic effect was confirmed in vitro by a dose-dependent inhibition of both receptor-dependent (using tumor necrosis factor and Fas ligand) and receptor-independent (staurosporine) caspase-3 induction in HT29 colonic epithelial cells. These data imply that caspase-3 activation is an early marker of colitis that is prevented by TUDCA treatment. These data, together with the previously reported beneficial effect in colitis, suggest that TUDCA could be an add-on strategy to current immunosuppressive treatment of UC patients. PMID:25310532

Laukens, Debby; Devisscher, Lindsey; Van den Bossche, Lien; Hindryckx, Pieter; Vandenbroucke, Roosmarijn E; Vandewynckel, Yves-Paul; Cuvelier, Claude; Brinkman, Brigitta M; Libert, Claude; Vandenabeele, Peter; De Vos, Martine

2014-12-01

274

Docosahexaenoic Acid Supplementation Early in Pregnancy May Prevent Deep Placentation Disorders  

PubMed Central

Uteroplacental ischemia may cause preterm birth, either due to preterm labor, preterm premature rupture of membranes, or medical indication (in the presence of preeclampsia or fetal growth restriction). Uteroplacental ischemia is the product of defective deep placentation, a failure of invasion, and transformation of the spiral arteries by the trophoblast. The failure of normal placentation generates a series of clinical abnormalities nowadays called “deep placentation disorders”; they include preeclampsia, fetal growth restriction, preterm labor, preterm premature rupture of membranes, in utero fetal death, and placental abruption. Early reports suggested that a LC-PUFAs (long chain polyunsaturated fatty acids) rich diet reduces the incidence of deep placentation disorders. Recent randomized controlled trials are inconsistent to show the benefit of docosahexaenoic acid (DHA) supplementation during pregnancy to prevent deep placentation disorders, but most of them showed that DHA supplementation was associated with lower risk of early preterm birth. We postulate that DHA supplementation, early in pregnancy, may reduce the incidence of deep placentation disorders. If our hypothesis is correct, DHA supplementation, early in pregnancy, will become a safe and effective strategy for primary prevention of highly relevant pregnancy diseases, such as preterm birth, preeclampsia, and fetal growth restriction. PMID:25019084

Carvajal, Jorge A.

2014-01-01

275

Lipoic acid prevents Cr(6+) induced cell transformation and the associated genomic dysregulation.  

PubMed

Investigation of the transcription profile of cells transformed by Cr(6+) in vivo was undertaken. The objective was to elucidate genomic changes underlying the mechanism of action of the carcinogenic dose of Cr(6+)and their prevention using metabolic antioxidant lipoic acid (LA). Cr(6+) was administered intraperitoneally to LPS+TPA challenged Swiss albino mice in host mediated cell transformation assay using peritoneal macrophages in vivo. The cell transforming potential of Cr(6+) test doses was validated by gain of anchorage independent growth potential in soft agar and loss of Fc receptor on target cells. LA was administered in equimolar doses. Compared to non-transformed cells, the gene expression profile of transformed cells was found to be dysregulated substantially and in dose dependent manner. Genes showing down regulation were found to be involved in tumour suppression, apoptosis, DNA repair, and cell-cycle. A similar response was noted in the genes pertaining to immune system, morphogenesis, cell-communication, energy-metabolism, and biosynthesis. The co-administration of lipoic acid prevented the transcription dysregulation and cell transformation by Cr(6+) in vivo. The influenced pathways seem to be crucial for progression as well as mitigation of Cr toxicity; and their response to LA indicated their critical role in mechanism of anti-carcinogenic action of LA. Results are of importance to mitigate Cr(6+) induced occupational cancer hazard. PMID:23608068

Kumar, Sushil; Nigam, Akanksha; Priya, Shivam; Bajpai, Preeti; Budhwar, Roli

2013-07-01

276

Regulation of transmural transport of amino acid/metal conjugates by dietary calcium in crustacean digestive tract.  

PubMed

Effects of luminal Ca(2+) and Mn(2+) on transmural mucosal to serosal (MS) transport of (3) H-L-leucine were characterized in the isolated and perfused intestine of the American lobster, Homarus americanus. (3) H-L-leucine MS transport in the presence of 20 µM Mn(2+) was a sigmoidal function of luminal amino acid concentration, following the Hill equation for multisite cooperative, carrier-mediated, transport. Luminal Ca(2+) was a non-competitive inhibitor of Mn(2+) -stimulated (3) H-L-leucine MS flux. Amino acid transport was hyperbolically stimulated by luminal Ca(2+) or Mn(2+). During 20 µM Mn(2+) -stimulation of (3) H-L-leucine MS flux, addition of 25 mM Ca(2+) strongly reduced amino acid transport Jmax , without affecting amino acid binding properties. Hyperbolic luminal Mn(2+) stimulation of 20 µM (3) H-L-leucine MS flux was also strongly inhibited by 25 mM luminal Ca(2+) , significantly reducing 20 µM (3) H-L-leucine Jmax . Increasing the luminal concentration of verapamil, a calcium channel blocker, significantly increased MS transport of 20 µM (3) H-L-leucine in the presence of 100 nM Mn(2+) by reducing diffusional Ca(2+) uptake into intestinal epithelial cells through verapamil-sensitive channels. A model is proposed supporting the concept of molecular mimicry, whereby (3) H-L-leucine enters lobster intestinal epithelial cells by one or more amino acid-specific transporters and by a dipeptide-like transporter that is capable of binding and transporting peptide molecular mimics (bis-complexes) between Ca(2+) or Mn(2+) and (3) H-L-leucine using the membrane potential as a major driving force for the transport event. According to the model, Ca(2+) entry through apical Ca(2+) channels regulates the magnitude of the membrane potential and therefore the size of the driving force for bis-complex uptake. PMID:24254522

Abdel-Malak, Rania; Ahearn, Gregory A

2014-03-01

277

Zoledronic acid at the time of castration prevented castration-induced bone metastasis in mice.  

PubMed

Androgen deprivation therapy (ADT) is known to cause bone loss in a majority of patients with castration-resistant prostate cancer (CRPC). A study published in this issue of Endocrine-Related Cancer by Ottewell and colleagues shows that ADT increased bone resorption and triggered growth of disseminated prostate cancer (CaP) cells to form bone metastasis using an in vivo model. However, prevention of bone decay by weekly administration of zoledronic acid (ZOL) at the time of castration prevented ADT-induced tumor growth in bone. Recently, two publications from Japan have demonstrated that ZOL combined with ADT improved outcomes for patients with treatment-naïve CaP with bone metastasis. The mechanistic cause for these patients having an improved overall survival compared with those who were treated with ZOL after ADT initiation or before metastasis development was never explained. Ottewell and colleague's study now suggests that it is the bone loss caused by ADT that promoted bone metastasis, and if ZOL is administered at the time of ADT initiation, it would prevent this bone loss and prolong skeletal-related event-free survival. PMID:25183429

Ghosh, Paramita M; Gao, Allen C

2014-10-01

278

Influence of fluoride, sulfate and acidity on extractable phosphorus, calcium, magnesium and potassium  

Microsoft Academic Search

In an attempt to develop an improved extractant for the soil test evaluation of plant available nutrients the influence of fluoride, sulfate and acidity on extractable P and Ca was investigated with 12 taxonomically different soils, (sequentially fractionated for Ca, Al, and Fe forms of phosphorus). The soils were extracted with 0.025, 0.05, 0.075 and 0.1N HCl alone and in

A. Mehlich

1978-01-01

279

Physiological and toxicological effects of long-term exposure to acid, aluminum, and low calcium on adult brook trout (Salvelinus fontinalis) and rainbow trout (Salmo gairdneri)  

SciTech Connect

Although the toxic effects of these three parameters were highly interactive, survival and growth of adult brook trout were reduced at elevated aluminum concentrations. Only 40 ug/L aluminum was necessary to produce similar responses in rainbow trout. Neither species was sensitive to pH alone in the range 4.5-6.5 except at very low calcium concentrations. Reductions in fecundity were observed, but only as a result of decreased growth. Progeny spawned from brook trout that had been exposed to 0.5 mg/L calcium were more sensitive to continued exposure to acid, aluminum and low calcium than were progeny of control fish. Physiologically, brook and rainbow trout responded similarly to sublethal acid, aluminum and low calcium stress. All fish exposed to depressed pH showed reductions in plasma sodium, but in most cases they were able to maintain normal plasma osmolality. But those fish stressed most severely displayed an entire suite of disturbances, including decreased survival, growth and feeding, as well as abnormal vitellogenesis and ionoregulatory failure.

Mount, D.R.

1987-01-01

280

Microwave-assisted synthesis of biocompatible europium-doped calcium hydroxyapatite and fluoroapatite luminescent nanospindles functionalized with poly(acrylic acid).  

PubMed

Europium-doped calcium hydroxyapatite and fluoroapatite nanophosphors functionalized with poly(acrylic acid) (PAA) have been synthesized through a one-pot microwave-assisted hydrothermal method from aqueous basic solutions containing calcium nitrate, sodium phosphate monobasic, and PAA, as well as sodium fluoride in the case of the fluoroapatite particles. In both cases a spindlelike morphology was obtained, resulting from an aggregation process of smaller subunits which also gave rise to high specific surface area. The size of the nanospindles was 191 (32) × 40 (5) nm for calcium hydroxyapatite and 152 (24) × 38 (6) nm for calcium fluoroapatite. The luminescent nanoparticles showed the typical red luminescence of Eu(3+), which was more efficient for the fluoroapatite particles than for the hydroxyapatite. This is attributed to the presence of OH(-) quenchers in the latter. The nanophosphors showed negligible toxicity for Vero cells. Both PAA-functionalized nanophosphors showed a very high (up to at least 1 week) colloidal stability in 2-(N-morpholino)ethanesulfonic acid (MES) at pH 6.5, which is a commonly used buffer for physiological pH. All these features make both kinds of apatite-based nanoparticles promising tools for biomedical applications, such as luminescent biolabels and tracking devices in drug delivery systems. PMID:23317411

Escudero, Alberto; Calvo, Mauricio E; Rivera-Fernández, Sara; de la Fuente, Jesús M; Ocaña, Manuel

2013-02-12

281

Nanouric acid or nanocalcium phosphate as central nidus to induce calcium oxalate stone formation: a high-resolution transmission electron microscopy study on urinary nanocrystallites  

PubMed Central

Purpose This study aimed to accurately analyze the relationship between calcium oxalate (CaOx) stone formation and the components of urinary nanocrystallites. Method High-resolution transmission electron microscopy (HRTEM), selected area electron diffraction, fast Fourier transformation of HRTEM, and energy dispersive X-ray spectroscopy were performed to analyze the components of these nanocrystallites. Results The main components of CaOx stones are calcium oxalate monohydrate and a small amount of dehydrate, while those of urinary nanocrystallites are calcium oxalate monohydrate, uric acid, and calcium phosphate. The mechanism of formation of CaOx stones was discussed based on the components of urinary nanocrystallites. Conclusion The formation of CaOx stones is closely related both to the properties of urinary nanocrystallites and to the urinary components. The combination of HRTEM, fast Fourier transformation, selected area electron diffraction, and energy dispersive X-ray spectroscopy could be accurately performed to analyze the components of single urinary nanocrystallites. This result provides evidence for nanouric acid and/or nanocalcium phosphate crystallites as the central nidus to induce CaOx stone formation. PMID:25258530

Gao, Jie; Xue, Jun-Fa; Xu, Meng; Gui, Bao-Song; Wang, Feng-Xin; Ouyang, Jian-Ming

2014-01-01

282

Omega-3 fatty acid oxidation products prevent vascular endothelial cell activation by coplanar polychlorinated biphenyls  

SciTech Connect

Coplanar polychlorinated biphenyls (PCBs) may facilitate development of atherosclerosis by stimulating pro-inflammatory pathways in the vascular endothelium. Nutrition, including fish oil-derived long-chain omega-3 fatty acids, such as docosahexaenoic acid (DHA, 22:6{omega}-3), can reduce inflammation and thus the risk of atherosclerosis. We tested the hypothesis that cyclopentenone metabolites produced by oxidation of DHA can protect against PCB-induced endothelial cell dysfunction. Oxidized DHA (oxDHA) was prepared by incubation of the fatty acid with the free radical generator 2,2-azo-bis(2-amidinopropane) dihydrochloride (AAPH). Cellular pretreatment with oxDHA prevented production of superoxide induced by PCB77, and subsequent activation of nuclear factor-{kappa}B (NF-{kappa}B). A{sub 4}/J{sub 4}-neuroprostanes (NPs) were identified and quantitated using HPLC ESI tandem mass spectrometry. Levels of these NPs were markedly increased after DHA oxidation with AAPH. The protective actions of oxDHA were reversed by treatment with sodium borohydride (NaBH{sub 4}), which concurrently abrogated A{sub 4}/J{sub 4}-NP formation. Up-regulation of monocyte chemoattractant protein-1 (MCP-1) by PCB77 was markedly reduced by oxDHA, but not by un-oxidized DHA. These protective effects were proportional to the abundance of A{sub 4}/J{sub 4} NPs in the oxidized DHA sample. Treatment of cells with oxidized eicosapentaenoic acid (EPA, 20:5{omega}-3) also reduced MCP-1 expression, but less than oxDHA. Treatment with DHA-derived cyclopentenones also increased DNA binding of NF-E2-related factor-2 (Nrf2) and downstream expression of NAD(P)H:quinone oxidoreductase (NQO1), similarly to the Nrf-2 activator sulforaphane. Furthermore, sulforaphane prevented PCB77-induced MCP-1 expression, suggesting that activation of Nrf-2 mediates the observed protection against PCB77 toxicity. Our data implicate A{sub 4}/J{sub 4}-NPs as mediators of omega-3 fatty acid-mediated protection against the endothelial toxicity of coplanar PCBs.

Majkova, Zuzana [Graduate Center for Toxicology, University of Kentucky, Lexington, KY 40536-0200 (United States); Layne, Joseph [Graduate Center for Nutritional Sciences, University of Kentucky, Lexington, KY 40536-0200 (United States); Sunkara, Manjula; Morris, Andrew J. [Division of Cardiovascular Medicine, The Gill Heart Institute, University of Kentucky, Lexington, KY 40536-0509 (United States); Toborek, Michal [Department of Neurosurgery, University of Kentucky, Lexington, KY 40536-0200 (United States); Hennig, Bernhard, E-mail: bhennig@email.uky.edu [Graduate Center for Toxicology, University of Kentucky, Lexington, KY 40536-0200 (United States); Graduate Center for Nutritional Sciences, University of Kentucky, Lexington, KY 40536-0200 (United States); Department of Animal and Food Sciences, University of Kentucky, Lexington, KY 40536-0200 (United States)

2011-02-15

283

Complex cardiac defects after ethanol exposure during discrete cardiogenic events in zebrafish: Prevention with folic acid  

PubMed Central

BACKGROUND Fetal alcohol spectrum disorder (FASD) describes a range of birth defects including various congenital heart defects (CHDs). Mechanisms of FASD-associated CHDs are not understood. Whether alcohol interferes with a single critical event or with multiple events in heart formation is not known. RESULTS Our zebrafish embryo experiments showed that ethanol interrupts different cardiac regulatory networks and perturbed multiple steps of cardiogenesis (specification, myocardial migration, looping, chamber morphogenesis and endocardial cushion formation). Ethanol exposure during gastrulation until cardiac specification or during myocardial midline migration did not produce severe or persistent heart development defects. However, exposure comprising gastrulation until myocardial precursor midline fusion or during heart patterning stages produced aberrant heart looping and defective endocardial cushions. Continuous exposure during entire cardiogenesis produced complex cardiac defects leading to severely defective myocardium, endocardium, and endocardial cushions. Supplementation of retinoic acid with ethanol partially rescued early heart developmental defects, but the endocardial cushions did not form correctly. In contrast, supplementation of folic acid rescued normal heart development, including the endocardial cushions. CONCLUSIONS Our results indicate that ethanol exposure interrupted divergent cardiac morphogenesis events causing heart defects. Folic acid supplementation was effective in preventing a wide spectrum of ethanol-induced heart developmental defects. PMID:23832875

Sarmah, Swapnalee; Marrs, James A.

2014-01-01

284

Crystal growth of calcium carbonate on the cellulose acetate/pyrrolidon blend films in the presence of L-aspartic acid  

NASA Astrophysics Data System (ADS)

The morphogenesis and growth process of calcium carbonate on the cellulose acetate/polyvinyl pyrrolidone (CA/PVP) blend films in the presence of L-aspartic acid was carefully investigated. The results showed that the concentration of L-aspartic acid, the initial pH value of reaction solution and temperature turned out to be important factors for the control of morphologies and polymorphs of calcium carbonate. Complex morphologies of CaCO3 particles, such as cubes, rose-like spheres, twinborn-spheres, cone-like, bouquet-like, etc. could be obtained under the different experimental conditions. The dynamic process of formation of rose-like sphere crystals was analyzed by monitoring the continuous morphological and structural evolution and components of crystals in different crystal stages. This research may provide a promising method to prepare other inorganic materials with complex morphologies.

Zhang, Xiuzhen; Xie, Anjian; Huang, Fangzhi; Shen, Yuhua

2014-03-01

285

A traditional Chinese herbal antilithic formula, Wulingsan, effectively prevents the renal deposition of calcium oxalate crystal in ethylene glycol-fed rats.  

PubMed

We investigated the effects of a traditional Chinese herbal formula, Wulingsan (WLS), on renal stone prevention using an ethylene glycol-induced nephrocalcinosis rat model. Forty-one male Sprague-Dawley (SD) rats were divided into four groups. Group 1 (n=8) was the normal control; group 2 (n=11) served as the placebo group, and received a gastric gavage of starch and 0.75% ethylene glycol (EG) as a stone inducer; group 3 received EG and a low dose of WLS (375 mg/kg); and group 4 received EG and a high dose of WLS (1,125 mg/kg). Baseline and final 24 h urine samples were collected individually; biochemical data of urine and serum were also obtained at the beginning and at the end of the experiment. After 4 weeks, animals were killed and kidneys were harvested. The kidney specimens were examined by polarized light microscopy and the crystal deposits were evaluated by a semi-quantitative scoring method using computer software (ImageScoring). The results revealed that the rats of placebo group gained the least significant body weight; in contrast, the rats of WLS-fed groups could effectively reverse it. The placebo group exhibited lower levels of free calcium (p=0.059) and significantly lower serum phosphorus (p=0.015) in urine than WLS-fed rats. Histological findings of kidneys revealed tubular destruction, damage and inflammatory reactions in the EG-water rats. The crystal deposit scores dropped significantly in the WLS groups, from 1.40 to 0.46 in the low-dose group and from 1.40 to 0.45 in the high-dose group. Overall, WLS effectively inhibited the deposition of calcium oxalate (CaOx) crystal and lowered the incidence of stones in rats (p=0.035). In conclusion, WLS significantly reduced the severity of calcium oxalate crystal deposits in rat kidneys, indicating that Wulingsan may be an effective antilithic herbal formula. PMID:18040675

Tsai, Chou-Huang; Chen, Yu-Cheng; Chen, Lieh-Der; Pan, Tien-Chien; Ho, Chien-Yi; Lai, Ming-Tsung; Tsai, Fuu-Jen; Chen, Wen-Chi

2008-02-01

286

Inhibition of polar calcium movement and gravitropism in roots treated with auxin-transport inhibitors  

NASA Technical Reports Server (NTRS)

Primary roots of maize (Zea mays L.) and pea (Pisum sativum L.) exhibit strong positive gravitropism. In both species, gravistimulation induces polar movement of calcium across the root tip from the upper side to the lower side. Roots of onion (Allium cepa L.) are not responsive to gravity and gravistimulation induces little or no polar movement of calcium across the root tip. Treatment of maize or pea roots with inhibitors of auxin transport (morphactin, naphthylphthalamic acid, 2,3,5-triiodobenzoic acid) prevents both gravitropism and gravity-induced polar movement of calcium across the root tip. The results indicate that calcium movement and auxin movement are closely linked in roots and that gravity-induced redistribution of calcium across the root cap may play an important role in the development of gravitropic curvature.

Lee, J. S.; Mulkey, T. J.; Evans, M. L.

1984-01-01

287

Hybrid calcium phosphate coatings with the addition of trace elements and polyaspartic acid by a low-thermal process.  

PubMed

Research in the field of orthopedic implantology is currently focused on developing methodologies to potentiate osseointegration and to expedite the reestablishment of full functionality. We have developed a simple biomimetic approach for preparing trace elements-codoped calcium phosphate (teCaP) coatings on a titanium substrate. The reaction proceeded via low-thermal incubation in trace elements (TEs)-added simulated body fluid (teSBF) at 90 and 120 °C. The x-ray photoelectron spectroscopy, x-ray diffraction and energy-dispersive x-ray analyses demonstrated that the teCaP coating was the composite of hydroxyapatite and whitlockite, simultaneously doped with magnesium, strontium, zinc and silicon. The addition of polyaspartic acid and TEs into SBF significantly densified the coating. The incubation temperature is another important factor controlling the coating precipitation rate and bonding strength. An incubation temperature of 120 °C could accelerate the coating precipitation and improve the interface bonding strength. The in vitro cell culture investigation indicated that the teCaP coating supported the adhesion and spreading of ovariectomized rat mesenchymal stem cells (rMSCs) and particularly, promoted rMSCs proliferation compared to the CaP coating prepared in SBF. Collectively, from such a biomimetic route there potentially arises a general procedure to prepare a wide range of bioactive teCaP coatings of different composition for osteoporotic osteogenic cells activation response. PMID:21487175

Xu, Sanzhong; Yang, Xianyan; Chen, Xiaoyi; Lin, Xiangjin; Zhang, Lei; Yang, Guojing; Gao, Changyou; Gou, Zhongru

2011-06-01

288

Calcium phenylphosphonate as a host for 4-aminobenzoic acid-Synthesis, characterization, and cation adsorption from ethanol solution  

SciTech Connect

Crystalline lamellar calcium phenylphosphonate retained 4-aminobenzoic acid inside its cavity without leaching. The intense infrared bands in the 1160-695 cm{sup -1} interval confirmed the presence of the phosphonate groups attached to the inorganic layer, with sharp and intense peaks in X-ray diffraction patterns, which gave basal distances of 1532 and 1751 pm for the original and the intercalated compounds, respectively. The thermogravimetric curves of both layered compounds showed the release of water molecules and the organic moiety in distinct stages, to yield a final Ca(PO{sub 3}){sub 2} residue. Solid-state {sup 31}P nuclear magnetic resonance spectra presented only one peak for the phenylphosphonate groups attached to the main inorganic polymeric structure near 12.4 ppm. The adsorption isotherms from ethanol gave the maximum adsorption capacities of 1.68 and 0.50 mmol g{sup -1} for copper and cobalt, respectively, whose average stability constants followed Co > Cu; the number of ligands was determined as four for both cations.

Lazarin, Angelica M., E-mail: amlazarin2@uem.br [Departamento de Quimica, Universidade Estadual de Maringa, Av. Colombo, 5790, 87020-900 Maringa, PR (Brazil); Ganzerli, Thiago A.; Sernaglia, Rosana L.; Andreotti, Elza I.S. [Departamento de Quimica, Universidade Estadual de Maringa, Av. Colombo, 5790, 87020-900 Maringa, PR (Brazil); Airoldi, Claudio [Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-971 Campinas, SP (Brazil)

2009-11-15

289

Long-term colloidal stability of 10 carbon nanotube types in the absence/presence of humic acid and calcium.  

PubMed

The colloidal stabilities of ten carbon nanotubes (CNTs) having varying physico-chemical properties were compared in long-term experiments. The presence of Suwannee River Humic Acid (SRHA) increased the fraction of CNTs in the supernatants (4-88% for the various CNT types) after addition in pre-dispersed form and 20 days of shaking and 5 days of settling. These suspensions were monomodal, containing individually suspended CNTs with highly negative surface charges. Calcium (2 mM) removed most of the CNT types from the supernatant, due to CNT-agglomerate formation initiated by reduction in surface charge. The amount of SRHA adsorbed to the different CNT types did not correlate (r(2) < 0.1) with the percentage of CNTs remaining in suspension. Multiple linear regression analysis revealed that the oxygen content and the diameter of the CNTs significantly influenced the percentage of stabilized CNTs, resulting in an increased fraction of functionalized and large-diameter CNTs that remained in suspension. PMID:22683482

Schwyzer, Irène; Kaegi, Ralf; Sigg, Laura; Smajda, Rita; Magrez, Arnaud; Nowack, Bernd

2012-10-01

290

Stimulated Efflux of Amino Acids and Glutathione from Cultured Hippocampal Slices by Omission of Extracellular Calcium  

PubMed Central

Omission of extracellular Ca2+ for 15 min from the incubation medium of cultured hippocampal slices stimulated the efflux of glutathione, phosphoethanolamine, hypotaurine, and taurine. The efflux was reduced by several blockers of gap junctions, i.e. carbenoxolone, flufenamic acid, and endothelin-1, and by the connexin43 hemichannel blocking peptide Gap26 but was unchanged by the P2X7 receptor inhibitor oxidized ATP, a pannexin1 hemichannel blocking peptide and an inactive analogue of carbenoxolone. Pretreatment of the slices with the neurotoxin N-methyl-d -aspartate left the efflux by Ca2+ omission unchanged, indicating that the stimulated efflux primarily originated from glia. Elevated glutamate efflux was detected when Ca2+ omission was combined with the glutamate uptake blocker l-trans-pyrrolidine-2,4-dicarboxylate and when both Ca2+ and Mg2+ were omitted from the medium. Omission of Ca2+ for 15 min alone did not induce delayed toxicity, but in combination with blocked glutamate uptake, significant cell death was observed 24 h later. Our results indicate that omission of extracellular Ca2+ stimulates efflux of glutathione and specific amino acids including glutamate via opening of glial hemichannels. This type of efflux may have protective functions via glutathione efflux but can aggravate toxicity in situations when glutamate reuptake is impaired, such as following a stroke. PMID:18272524

Stridh, Malin H.; Tranberg, Mattias; Weber, Stephen G.; Blomstrand, Fredrik; Sandberg, Mats

2008-01-01

291

Development and characterization of nanofibrous poly(lactic- co -glycolic acid)\\/biphasic calcium phosphate composite scaffolds for enhanced osteogenic differentiation  

Microsoft Academic Search

Poly(lactic-co-glycolic acid)(PLGA)\\/biphasic calcium phosphate (BCP) composite nanofibers with different BCP to PLGA ratios were fabricated\\u000a using the electrospinning technique. The scanning electron microscopy (SEM) images showed a similar morphology and fibers\\u000a in all groups. The incorporated BCP was dispersed homogenously throughout the nanofibers, and the surface roughness was affected\\u000a by the input amount of BCP. The increase in amount of

Ji-Hye Lee; Yu-Bin Lee; Nae-Gyune Rim; Sun-Young Jo; Youn-Mook Lim; Heungsoo Shin

2011-01-01

292

Effect of low-carbohydrate high-protein diets on acid-base balance, stone-forming propensity, and calcium metabolism  

Microsoft Academic Search

Background: Low-carbohydrate high-protein (LCHP) diets are used commonly for weight reduction. This study explores the relationship between such diets and acid-base balance, kidney-stone risk, and calcium and bone metabolism. Methods: Ten healthy subjects participated in a metabolic study. Subjects initially consumed their usual non-weight-reducing diet, then a severely carbohydrate-restricted induction diet for 2 weeks, followed by a moderately carbohydrate-restricted maintenance

Shalini T. Reddy; Chia-Ying Wang; Khashayar Sakhaee; Linda Brinkley; Charles Y. C. Pak

2002-01-01

293

Increased fecal bile acid excretion and changes in the circulating bile acid pool are involved in the hypocholesterolemic and gallstone-preventive actions of psyllium in hamsters.  

PubMed

The lipid-lowering effect of psyllium (PSY) is well established. Enhanced fecal bile acid excretion and a stimulation of hepatic bile acid synthesis are discussed as primary mechanisms of this action. To further examine the effect of bile acid excretion and specifically of compositional alterations in the bile acid pool on the cholesterol-lowering and gallstone-preventing action of PSY, male golden Syrian hamsters were fed lithogenic diets containing 5 g/100 g fat, 0.4 g/100 g cholesterol and 0 (control), 4 or 6% PSY or 1% cholestyramine (CHY). PSY significantly lowered plasma total cholesterol and triacylglycerol at a magnitude comparable to that induced by CHY. Although hepatic cholesteryl ester accumulation was completely inhibited by CHY, PSY did not prevent the hepatic storage of esterified cholesterol. PSY and CHY caused distinct alterations in the bile acid profile. PSY caused a selective reduction of taurine-conjugated bile acids, especially of taurochenodeoxycholate. As a result, the glycine:taurine conjugation and the cholate:chenodeoxycholate ratios were significantly higher in PSY-fed hamsters. PSY and CHY normalized the lithogenic index and prevented cholesterol gallstone formation compared with controls. Daily fecal bile acid excretion was approximately 400% greater in hamsters fed 6% PSY, whereas CHY caused an 11-fold increase. Daily neutral sterol excretion did not differ in PSY-fed hamsters but was >100% greater in those fed CHY than in controls. These data emphasize the potent lipid-lowering effect of PSY. Increased fecal bile acid excretion and alterations of the circulating bile acid pool by removal of dihydroxy bile acids (e.g., taurochenodeoxycholate) appear to be main modulators of the hypocholesterolemic action of PSY by leading to an up-regulation of hepatic bile acid synthesis. PMID:10203567

Trautwein, E A; Kunath-Rau, A; Erbersdobler, H F

1999-04-01

294

Calcium and Vitamin D  

Technology Transfer Automated Retrieval System (TEKTRAN)

Adequate intakes of vitamin D and calcium are essential preventative measures and essential components of any therapeutic regimen for osteoporosis. Vitamin D is also important for the prevention of falls. Current evidence suggests that a 25-hydroxyvitamin D level of 75 nmol/L (30 ng/ml) or higher ...

295

Tachikawa project for prevention of posttraumatic stress disorder with polyunsaturated fatty acid (TPOP): study protocol for a randomized controlled trial  

PubMed Central

Background Preclinical and clinical studies suggest that supplementation with omega-3 fatty acids after trauma might reduce subsequent posttraumatic stress disorder (PTSD). To date, we have shown in an open trial that PTSD symptoms in critically injured patients can be reduced by taking omega-3 fatty acids, hypothesized to stimulate hippocampal neurogenesis. The primary aim of the present randomized controlled trial is to examine the efficacy of omega-3 fatty acid supplementation in the secondary prevention of PTSD following accidental injury, as compared with placebo. This paper describes the rationale and protocol of this trial. Methods/design The Tachikawa Project for Prevention of Posttraumatic Stress Disorder with Polyunsaturated Fatty Acid (TPOP) is a double-blinded, parallel group, randomized controlled trial to assess whether omega-3 fatty acid supplementation can prevent PTSD symptoms among accident-injured patients consecutively admitted to an intensive care unit. We plan to recruit accident-injured patients and follow them prospectively for 12 weeks. Enrolled patients will be randomized to either the omega-3 fatty acid supplement group (1,470 mg docosahexaenoic acid and 147 mg eicosapentaenoic acid daily) or placebo group. Primary outcome is score on the Clinician-Administered PTSD Scale (CAPS). We will need to randomize 140 injured patients to have 90% power to detect a 10-point difference in mean CAPS scores with omega-3 fatty acid supplementation compared with placebo. Secondary measures are diagnosis of PTSD and major depressive disorder, depressive symptoms, physiologic response in the experiment using script-driven imagery and acoustic stimulation, serum brain-derived neurotrophic factor, health-related quality of life, resilience, and aggression. Analyses will be by intent to treat. The trial was initiated on December 13 2008, with 104 subjects randomized by November 30 2012. Discussion This study promises to be the first trial to provide a novel prevention strategy for PTSD among traumatized people. Trial registration ClinicalTrials.gov Identifier NCT00671099 PMID:23289548

2013-01-01

296

Water, acid, and calcium carbonate pretreatment of fly ash: The effect on setting of cement-fly ash mixtures  

SciTech Connect

The treatment of class C, I, and F fly ash (FA) with water, HNO{sub 3}, and aqueous CaCO{sub 3} has been investigated to develop a simple chemical route to change the morphology and surface chemistry of fly ash particles to enhance the setting properties of a cement/fly ash (C/FA) composite. The treatment of C-FA with an aqueous CaCO{sub 3} solution results in a dramatic improvement in the setting time and the setting profile on C-class FA; in contrast, the treatment has no effect on the set time for F-FA and reduces the set time and appears to result in an even more nonideal induction setting curve as compared to the untreated C/I-FA. The enhancement observed for the treatment of C-FA with aqueous CaCO{sub 3} solution is not a consequence of the water solution since simply washing with water (i.e., C-FA(H{sub 2}O)) results in the extraction of Na and Ca with a concomitant increase in surface area and a performance similar to those observed for untreated I-FA and F-FA despite a much higher surface area. The acid (HNO{sub 3}) treatment of I-FA and F-FA results in the formation of an inert filler-like material, while acid treatment of C-FA results in a material with completely undesirable setting properties. Clearly, the enhancements observed for the aqueous CaCO{sub 3} treatment are not as a result of simply either the aqueous or acidic nature of the HCO{sub 3} containing CaCO{sub 3} solution. Based upon the forgoing, we propose that the efficacy of the aqueous CaCO{sub 3} treatment on C-FA is associated with the availability of 'reactive calcium'. Exposure of C-FA to dry CO{sub 2} does not affect the set time or set profile for C/C-FA mixture, but the retarding effect of the aqueous CaCO{sub 3} treatment on C-FA can be replicated by the exposure of the C-FA to a stepwise reaction with water and CO{sub 2}. Exposure of C-FA to wet CO{sub 2} results in the improvement of the setting induction profile without significantly affecting the set time.

Lupu, C.; Jackson, K.L.; Bard, S.; Barron, A.R. [Rice University, Houston, TX (United States)

2007-11-15

297

Acacetin inhibits glutamate release and prevents kainic acid-induced neurotoxicity in rats.  

PubMed

An excessive release of glutamate is considered to be a molecular mechanism associated with several neurological diseases that causes neuronal damage. Therefore, searching for compounds that reduce glutamate neurotoxicity is necessary. In this study, the possibility that the natural flavone acacetin derived from the traditional Chinese medicine Clerodendrum inerme (L.) Gaertn is a neuroprotective agent was investigated. The effect of acacetin on endogenous glutamate release in rat hippocampal nerve terminals (synaptosomes) was also investigated. The results indicated that acacetin inhibited depolarization-evoked glutamate release and cytosolic free Ca(2+) concentration ([Ca(2+)]C) in the hippocampal nerve terminals. However, acacetin did not alter synaptosomal membrane potential. Furthermore, the inhibitory effect of acacetin on evoked glutamate release was prevented by the Cav2.2 (N-type) and Cav2.1 (P/Q-type) channel blocker known as ?-conotoxin MVIIC. In a kainic acid (KA) rat model, an animal model used for excitotoxic neurodegeneration experiments, acacetin (10 or 50 mg/kg) was administrated intraperitoneally to the rats 30 min before the KA (15 mg/kg) intraperitoneal injection, and subsequently induced the attenuation of KA-induced neuronal cell death and microglia activation in the CA3 region of the hippocampus. The present study demonstrates that the natural compound, acacetin, inhibits glutamate release from hippocampal synaptosomes by attenuating voltage-dependent Ca(2+) entry and effectively prevents KA-induced in vivo excitotoxicity. Collectively, these data suggest that acacetin has the therapeutic potential for treating neurological diseases associated with excitotoxicity. PMID:24520409

Lin, Tzu-Yu; Huang, Wei-Jan; Wu, Chia-Chan; Lu, Cheng-Wei; Wang, Su-Jane

2014-01-01

298

Polyglycolic acid sheets with fibrin glue can prevent esophageal stricture after endoscopic submucosal dissection.  

PubMed

Background and study aims: Suitable techniques for the prevention of stricture formation after esophageal endoscopic submucosal dissection (ESD) are still lacking. We investigated the efficacy of polyglycolic acid (PGA) sheets with fibrin glue to prevent post-ESD stricture. Patients and methods: We conducted a pilot study on a total of eight consecutive patients who underwent esophageal ESD that left a mucosal defect of more than three-quarters of the esophageal circumference. PGA sheets were attached to the defect with fibrin glue immediately after the completion of ESD. The primary endpoint was the incidence of post-ESD stricture. The secondary endpoints were the number of sessions of endoscopic balloon dilation (EBD) required to resolve any stricture and the rate of complications. Results: There were no adverse events related to the use of PGA sheets and fibrin glue. Post-ESD stricture occurred in 37.5?% of the subjects and 0.8 ± 1.2 sessions of EBD were required. Conclusion: The use of PGA sheets and fibrin glue after esophageal ESD is a novel method that radically decreases the incidence of esophageal stricture and the number of EBD sessions subsequently required. University Hospital Medical Network Clinical Trial Registry (UMIN000011058). PMID:25314328

Sakaguchi, Yoshiki; Tsuji, Yosuke; Ono, Satoshi; Saito, Itaru; Kataoka, Yosuke; Takahashi, Yu; Nakayama, Chiemi; Shichijo, Satoki; Matsuda, Rie; Minatsuki, Chihiro; Asada-Hirayama, Itsuko; Niimi, Keiko; Kodashima, Shinya; Yamamichi, Nobutake; Fujishiro, Mitsuhiro; Koike, Kazuhiko

2014-10-14

299

Acacetin Inhibits Glutamate Release and Prevents Kainic Acid-Induced Neurotoxicity in Rats  

PubMed Central

An excessive release of glutamate is considered to be a molecular mechanism associated with several neurological diseases that causes neuronal damage. Therefore, searching for compounds that reduce glutamate neurotoxicity is necessary. In this study, the possibility that the natural flavone acacetin derived from the traditional Chinese medicine Clerodendrum inerme (L.) Gaertn is a neuroprotective agent was investigated. The effect of acacetin on endogenous glutamate release in rat hippocampal nerve terminals (synaptosomes) was also investigated. The results indicated that acacetin inhibited depolarization-evoked glutamate release and cytosolic free Ca2+ concentration ([Ca2+]C) in the hippocampal nerve terminals. However, acacetin did not alter synaptosomal membrane potential. Furthermore, the inhibitory effect of acacetin on evoked glutamate release was prevented by the Cav2.2 (N-type) and Cav2.1 (P/Q-type) channel blocker known as ?-conotoxin MVIIC. In a kainic acid (KA) rat model, an animal model used for excitotoxic neurodegeneration experiments, acacetin (10 or 50 mg/kg) was administrated intraperitoneally to the rats 30 min before the KA (15 mg/kg) intraperitoneal injection, and subsequently induced the attenuation of KA-induced neuronal cell death and microglia activation in the CA3 region of the hippocampus. The present study demonstrates that the natural compound, acacetin, inhibits glutamate release from hippocampal synaptosomes by attenuating voltage-dependent Ca2+ entry and effectively prevents KA-induced in vivo excitotoxicity. Collectively, these data suggest that acacetin has the therapeutic potential for treating neurological diseases associated with excitotoxicity. PMID:24520409

Lin, Tzu-Yu; Huang, Wei-Jan; Wu, Chia-Chan; Lu, Cheng-Wei; Wang, Su-Jane

2014-01-01

300

The ?6-fatty acid, arachidonic acid, regulates the conversion of white to brite adipocyte through a prostaglandin/calcium mediated pathway  

PubMed Central

Objective Brite adipocytes are inducible energy-dissipating cells expressing UCP1 which appear within white adipose tissue of healthy adult individuals. Recruitment of these cells represents a potential strategy to fight obesity and associated diseases. Methods/Results Using human Multipotent Adipose-Derived Stem cells, able to convert into brite adipocytes, we show that arachidonic acid strongly inhibits brite adipocyte formation via a cyclooxygenase pathway leading to secretion of PGE2 and PGF2?. Both prostaglandins induce an oscillatory Ca++ signaling coupled to ERK pathway and trigger a decrease in UCP1 expression and in oxygen consumption without altering mitochondriogenesis. In mice fed a standard diet supplemented with ?6 arachidonic acid, PGF2? and PGE2 amounts are increased in subcutaneous white adipose tissue and associated with a decrease in the recruitment of brite adipocytes. Conclusion Our results suggest that dietary excess of ?6 polyunsaturated fatty acids present in Western diets, may also favor obesity by preventing the “browning” process to take place. PMID:25506549

Pisani, Didier F.; Ghandour, Rayane A.; Beranger, Guillaume E.; Le Faouder, Pauline; Chambard, Jean-Claude; Giroud, Maude; Vegiopoulos, Alexandros; Djedaini, Mansour; Bertrand-Michel, Justine; Tauc, Michel; Herzig, Stephan; Langin, Dominique; Ailhaud, Gérard; Duranton, Christophe; Amri, Ez-Zoubir

2014-01-01

301

Ferulic acid prevents liver injury and increases the anti-tumor effect of diosbulbin B in vivo *  

PubMed Central

The present study is designed to investigate the protection by ferulic acid against the hepatotoxicity induced by diosbulbin B and its possible mechanism, and further observe whether ferulic acid augments diosbulbin B-induced anti-tumor activity. The results show that ferulic acid decreases diosbulbin B-increased serum alanine transaminase/aspartate transaminase (ALT/AST) levels. Ferulic acid also decreases lipid peroxide (LPO) levels which are elevated in diosbulbin B-treated mice. Histological evaluation of the liver demonstrates hydropic degeneration in diosbulbin B-treated mice, while ferulic acid reverses this injury. Moreover, the activities of copper- and zinc-containing superoxide dismutase (CuZn-SOD) and catalase (CAT) are decreased in the livers of diosbulbin B-treated mice, while ferulic acid reverses these decreases. Further results demonstrate that the mRNA expressions of CuZn-SOD and CAT in diosbulbin B-treated mouse liver are significantly decreased, while ferulic acid prevents this decrease. In addition, ferulic acid also augments diosbulbin B-induced tumor growth inhibition compared with diosbulbin B alone. Taken together, the present study shows that ferulic acid prevents diosbulbin B-induced liver injury via ameliorating diosbulbin B-induced liver oxidative stress injury and augments diosbulbin B-induced anti-tumor activity. PMID:24903991

Wang, Jun-ming; Sheng, Yu-chen; Ji, Li-li; Wang, Zheng-tao

2014-01-01

302

Acid-sensitive channel inhibition prevents fetal alcohol spectrum disorders cerebellar Purkinje cell loss  

NSDL National Science Digital Library

Ethanol is now considered the most common human teratogen. Educational campaigns have not reduced the incidence of ethanol-mediated teratogenesis, leading to a growing interest in the development of therapeutic prevention or mitigation strategies. On the basis of the observation that maternal ethanol consumption reduces maternal and fetal pH, we hypothesized that a pH-sensitive pathway involving the TWIK-related acid-sensitive potassium channels (TASKs) is implicated in ethanol-induced injury to the fetal cerebellum, one of the most sensitive targets of prenatal ethanol exposure. Pregnant ewes were intravenously infused with ethanol (258 ± 10 mg/dl peak blood ethanol concentration) or saline in a "3 days/wk binge" pattern throughout the third trimester. Quantitative stereological analysis demonstrated that ethanol resulted in a 45% reduction in the total number of fetal cerebellar Purkinje cells, the cell type most sensitive to developmental ethanol exposure. Extracellular pH manipulation to create the same degree and pattern of pH fall caused by ethanol (manipulations large enough to inhibit TASK 1 channels), resulted in a 24% decrease in Purkinje cell number. We determined immunohistochemically that TASK 1 channels are expressed in Purkinje cells and that the TASK 3 isoform is expressed in granule cells of the ovine fetal cerebellum. Pharmacological blockade of both TASK 1 and TASK 3 channels simultaneous with ethanol effectively prevented any reduction in fetal cerebellar Purkinje cell number. These results demonstrate for the first time functional significance of fetal cerebellar two-pore domain pH-sensitive channels and establishes them as a potential therapeutic target for prevention of ethanol teratogenesis.

Jay Ramadoss (University of Wisconsin)

2008-05-22

303

Nordihydroguairetic acid, a lignin, prevents oxidative stress and the development of diabetic nephropathy in rats.  

PubMed

Recent evidences indicate a pivotal role of reactive oxygen species in etiology of diabetic nephropathy, an important microvascular complication of diabetes mellitus. Moreover, oxidative stress leads to an increased production of lipoxygenase derivatives which also play a role in diabetic nephropathy. The present study was thus designed to examine the effect of an antioxidant and a lipoxygenase inhibitor, nordihydroguairetic acid (NDGA), on renal function and oxidative stress in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by a single intraperitoneal injection of streptozotocin (65 mg/kg) in rats. After the 4th week of STZ injection, NDGA (5 and 10 mg/kg) was given subcutaneously (s.c.) for another 4 weeks to both control and diabetic rats. At the end of the 8th week, diabetic rats exhibited renal dysfunction as evidenced by reduced creatinine and urea clearance along with enhanced albumin excretion rate as compared with control rats. Biochemical analysis of kidneys revealed a marked increase in oxidative stress demonstrated by increased lipid peroxidation and decreased activities of key antioxidant enzymes, glutathione (GSH), superoxide dismutase (SOD) and catalase in diabetic rats. Chronic treatment with NDGA in diabetic rats significantly prevented both renal dysfunction and oxidative stress as compared with vehicle-treated diabetic rats. The kidneys of diabetic rats showed morphological changes such as hyaline casts, glomerular thickening and moderate interstitial fibrosis and arteriolopathy, whereas NDGA administration in diabetic rats markedly prevented renal morphological alterations. These results emphasize the role of oxidative stress in the pathophysiology of diabetic nephropathy and point towards the potential of NDGA as a complementary therapy for the prevention/treatment of diabetic nephropathy. PMID:15292654

Anjaneyulu, Muragundla; Chopra, Kanwaljit

2004-09-01

304

Assessment of high performance concrete containing fly ash and calcium nitrite based corrosion inhibitor as a mean to prevent the corrosion of reinforcing steel  

NASA Astrophysics Data System (ADS)

This research analyses the effectiveness of the water-to-cement ratio (w/c), fly ash and a calcium nitrite based corrosion inhibitor to prevent the corrosion of reinforcing steel embedded in high performance concrete. The interactive effect between the inhibitor and fly ash was evaluated because the occurrence of a negative effect when both ingredients are added together in a concrete mixture has been reported. All the concrete mixtures studied in this investigation had 8.2% of silica fume. Twenty seven prismatic concrete specimens were fabricated with dimensions of 55 × 230 × 300 mm each containing two steel rods embedded for the purpose of corrosion monitoring. The specimens were exposed to a simulated marine environment with two daily cycles of wetting and drying for one year. To evaluate the deterioration of the specimens corrosion potentials and linear polarization resistance tests were carried out. The results indicate that the use of a low w/c, the addition of fly ash and the addition of the corrosion inhibitor contributed to the reduction of the corrosion of steel in the concrete specimens. The results further suggest that the combination of fly ash and corrosion inhibitor does not promote the deterioration of the concrete matrix.

Montes-García, P.; Jiménez-Quero, V.; López-Calvo, H.

2015-01-01

305

The role of calcium and nicotinic acid adenine dinucleotide phosphate (NAADP) in human osteoclast formation and resorption.  

PubMed

Osteoclasts are specialised bone resorbing cells which form by fusion of circulating mononuclear phagocyte precursors. Bone resorption results in the release of large amounts of calcium into the extracellular fluid (ECF), but it is not certain whether changes in extracellular calcium concentration [Ca(2+)]e influence osteoclast formation and resorption. In this study, we sought to determine the effect of [Ca(2+)]e and NAADP, a potent calcium mobilising messenger that induces calcium uptake, on human osteoclast formation and resorption. CD14+ human monocytes were cultured with M-CSF and RANKL in the presence of different concentrations of calcium and NAADP and the effect on osteoclast formation and resorption evaluated. We found that the number of TRAP+ multinucleated cells and the extent of lacunar resorption were reduced when there was an increase in extracellular calcium and NAADP. This was associated with a decrease in RANK mRNA expression by CD14+ cells. At high concentrations (20 mM) of [Ca(2+)]e mature osteoclast resorption activity remained unaltered relative to control cultures. Our findings indicate that osteoclast formation is inhibited by a rise in [Ca(2+)]e and that RANK expression by mononuclear phagocyte osteoclast precursors is also [Ca(2+)]e dependent. Changes in NAADP also influence osteoclast formation, suggesting a role for this molecule in calcium handling. Osteoclasts remained capable of lacunar resorption, even at high ECF [Ca(2+)]e, in keeping with their role in physiological and pathological bone resorption. PMID:25433853

Cheng, X; Hookway, E S; Kashima, T; Oppermann, U; Galione, A; Athanasou, N A

2015-01-01

306

Sulfur mustard-induced increase in intracellular free calcium level and arachidonic acid release from cell membrane  

SciTech Connect

The mechanism of action of the alkylating agent bis-(2-chloroethyl)sulfide (sulfur mustard, SM) was studied using the in thai vitro mouse neuroblastoma-rat glioma hybrid NG 108-1 S clonal p cell line model. Following 0.3 mM SM exposure, cell viability remained high (>80% of untreated control) up to 9 hr and then declined steadily to about 40% of control after 20-24 hr. During the early period of SM exposure, when there was no significant cell viability loss, the following effects were observed. The cellular glutathione level decreased 20% after 1 hr and 34% after 6 hr. Between 2 and 6 hr, there was a time-dependent increase (about 10 to 30%) in intracellular free calcium (Ca2+), which was localized to the limiting membrane of swollen endoplasmic reticula and mitochondria, to euchromatin areas of the nucleus, and to areas of the cytosol and plasma membrane. Moreover,there was also a time-dependent increase in the release of isotopically labeled arachidonic acid ((3H)AA) from cellular membranes. Increase in (3H)AA release was 28% at 3 hr and about 60-80% between 6 and 9 hr. This increase in I3HIAA release was inhibited by quinacrine (20 uM), which is a phospholipase (PLA2) inhibitor. At 16 hr after SM exposure, there was a large increase (about 200% of control) in I3HIAA release, which was coincident with a 50% loss of cell viability. These results suggest a Ca2+-mediated toxic mechanism of SM via PLA2 activation and arachidonate release.

Ray, R.; Legere, R.H.; Majerus, B.J.; Petrali, J.P.

1995-12-31

307

Changes of extracellular calcium concentration induced by application of excitatory amino acids in the human neocortex in vitro.  

PubMed

The influence of the glutamate subreceptor agonists N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) on cortical field potentials and on changes in extracellular free calcium concentration ([Ca2+]o) was tested on human neocortical slices (eleven from nine different patients). The tissue used was a small portion of that which is normally removed for the treatment of a brain tumor. [Ca2+]o and field potentials were measured by Ca(2+)-selective microelectrodes. Local pressure-microejection of NMDA (100 mumol/l)- and AMPA (1 mmol/l)-induced negative field potentials with maximal amplitudes of 0.9 +/- 0.1 mV (11 slices, mean +/- S.E.M.) and 1.0 +/- 0.1 mV (nine slices), respectively. The negative field potentials induced by NMDA were accompanied by monophasic decreases of [Ca2+]o (0.8 +/- 0.1 mmol/l, nine slices). AMPA elicited no (three slices) or only minor decreases of [Ca2+]o (0.2 +/- 0.1 mmol/l, five slices). The responses to the glutamate subreceptor agonists NMDA and AMPA were reversibly depressed by adding their specific antagonists DL-2-amino-5-phosphonovalerate (APV, 100 mumol/l, six slices) and 6-cyano-7-nitroquinoxalin-2,3-dion (CNQX, 5 mumol/l, four slices), respectively. The results correspond to findings in animal experiments and are consistent with the interpretation that in the human neocortex the Ca2+ permeability of channels gated by NMDA is higher than those gated by AMPA. PMID:7538028

Lücke, A; Köhling, R; Straub, H; Moskopp, D; Wassmann, H; Speckmann, E J

1995-02-13

308

Calcium - urine  

MedlinePLUS

... best treatment for the most common type of kidney stone , which is made of calcium. This type of ... the kidneys into the urine, which causes calcium kidney stones Sarcoidosis Taking too much calcium Too much production ...

309

Calcium Carbonate  

MedlinePLUS

Calcium carbonate is a dietary supplement used when the amount of calcium taken in the diet is not ... for healthy bones, muscles, nervous system, and heart. Calcium carbonate also is used as an antacid to relieve ...

310

21 CFR 184.1229 - Calcium stearate.  

Code of Federal Regulations, 2010 CFR

...1229 Calcium stearate. (a) Calcium stearate (Ca(C17 H35 COO...Reg. No. 1529-23-0) is the calcium salt of stearic acid derived...as a white precipitate by mixing calcium chloride and sodium stearate in...

2010-04-01

311

National Osteoporosis Prevention Month  

E-print Network

MAY National Osteoporosis Prevention Month JUNE National Dairy Month Texas AgriLife Extension Service Texas A&M University System Eat Smart for Bone Health Calcium & Vitamin D - Lesson 5 Contents: Lesson - Calcium & Vitamin D Power Point # P5-1 Eat Smart for Bone Health # P5-2 Calcium Consumption # P5

312

Renal Outcomes in High-Risk Hypertensive Patients Treated With an Angiotensin-Converting Enzyme Inhibitor or a Calcium Channel Blocker vs. a Diuretic. A Report From the Antihypertensive and Lipid-lowering Treatment to Prevent Heart Attack Trial (ALLHAT)  

Microsoft Academic Search

Background: This study was performed to determine whether, in high-risk hypertensive patients with a re- duced glomerular filtration rate (GFR), treatment with a calcium channel blocker or an angiotensin-converting enzyme inhibitor lowers the incidence of renal disease outcomes compared with treatment with a diuretic. Methods: We conducted post hoc analyses of the Anti- hypertensive and Lipid-Lowering Treatment to Prevent Heart

Mahboob Rahman; Sara Pressel; Barry R. Davis

2005-01-01

313

Eicosapentaenoic acid prevents high fat diet-induced metabolic disorders: Genomic and metabolomic analyses of underlying mechanism  

Technology Transfer Automated Retrieval System (TEKTRAN)

Previously our lab demonstrated eicosapenaenoic acid (EPA)'s ability to prevent high-fat (HF) diet-induced obesity by decreasing insulin resistance, glucose intolerance and inflammation. In the current study, we used genomic and metabolomic approaches to further investigate the molecular basis for t...

314

Zoledronic Acid Versus Alendronate for the Prevention of Bone Loss after Heart or Liver Transplantation  

PubMed Central

Context: The first year after transplantation is characterized by rapid bone loss. Objective: The aim of this study was to compare zoledronic acid (zoledronate) and alendronate for prevention of transplantation bone loss. Design and Setting: A randomized clinical trial was conducted at a transplantation center. Patients: The study included 84 adults undergoing heart or liver transplantation and a concurrently transplanted, nonrandomized reference group of 27 adults with T scores greater than ?1.5. Interventions: Alendronate (70 mg weekly for 12 months) or one 5-mg infusion of zoledronate were both initiated 26 ± 8 d after transplantation. Main Outcome Measures: The primary outcome was total hip bone mineral density (BMD) 1 yr after transplantation. Secondary outcomes included femoral neck and lumbar spine BMD and serum C-telopeptide, a bone resorption marker. Results: In the reference group, BMD declined at the spine and hip (P < 0.001). In the randomized groups, hip BMD remained stable. Spine BMD increased in the zoledronate group and did not change in the alendronate group; at 12 months, the 2.2% difference between groups (95% confidence interval, 0.6 to 3.9%; P = 0.009) favored zoledronate. In heart transplant patients, spine BMD declined in the alendronate and increased in the zoledronate group (?3.0 vs. +1.6%, respectively; between-group difference, 4.2%; 95% confidence interval, 2.1 to 6.3%; P < 0.001). In liver transplant patients, spine BMD increased comparably in both groups. Twelve-month C-telopeptide was lower in the zoledronate group than in the alendronate group (79 vs. 49%; P = 0.04). Conclusions: One 5-mg infusion of zoledronate and weekly alendronate prevent bone loss at the hip and, in liver transplant patients, increase spine BMD. In heart transplant patients, spine bone BMD remained stable with zoledronate but decreased with alendronate. PMID:23024190

Cohen, Adi; Stein, Emily M.; McMahon, Donald J.; Zhang, Chiyuan; Young, Polly; Pandit, Kavita; Staron, Ronald B.; Verna, Elizabeth C.; Brown, Robert; Restaino, Susan; Mancini, Donna

2012-01-01

315

Improved biocompatibility of poly(lactic-co-glycolic acid) orv and poly-L-lactic acid blended with nanoparticulate amorphous calcium phosphate in vascular stent applications.  

PubMed

Biodegradable polymers used as vascular stent coatings and stent platforms encounter a major challenge: biocompatibility in vivo, which plays an important role in in-stent restenosis (ISR). Co-formulating amorphous calcium phosphate (ACP) into poly(lactic-co-glycolic acid) (PLGA) or poly-L-lactic acid (PLLA) was investigated to address the issue. For stent coating applications, metal stents were coated with polyethylene-co-vinyl acetate/poly-n-butyl methacrylate (PEVA/PBMA), PLGA or PLGA/ACP composites, and implanted into rat aortas for one and three months. Comparing with both PEVA/PBMA and PLGA groups after one month, the results showed that stents coated with PLGA/ACP had significantly reduced restenosis (PLGA/ACP vs. PEVA/PBMA vs. PLGA: 21.24 +/- 2.59% vs. 27.54 +/- 1.19% vs. 32.12 +/- 3.93%, P < 0.05), reduced inflammation (1.25 +/- 0.35 vs. 1.77 +/- 0.38 vs. 2.30 +/- 0.21, P < 0.05) and increased speed of re-endothelialization (1.78 +/- 0.46 vs. 1.17 +/- 0.18 vs. 1.20 +/- 0.18, P < 0.05). After three months, the PLGA/ACP group still displayed lower inflammation score (1.33 +/- 0.33 vs. 2.27 +/- 0.55, P < 0.05) and higher endothelial scores (2.33 +/- 0.33 vs. 1.20 +/- 0.18, P < 0.05) as compared with the PEVA/PBMA group. Moreover, for stent platform applications, PLLA/ACP stent tube significantly reduced the inflammatory cells infiltration in the vessel walls of rabbit iliac arteries relative to their PLLA cohort (NF-kappaB-positive cells: 23.31 +/- 2.33/mm2 vs. 9.34 +/- 1.35/mm2, P < 0.05). No systemic biochemical or pathological evidence of toxicity was found in either PLGA/ACP or PLLA/ACP. The co-formulation of ACP into PLGA and PLLA resulted in improved biocompatibility without systemic toxicity. PMID:24749387

Zheng, Xiaoxin; Wang, Yujue; Lan, Zhiyuan; Lyu, Yongnan; Feng, Gaoke; Zhang, Yipei; Tagusari, Shizu; Kislauskis, Edward; Robich, Michael P; McCarthy, Stephen; Sellke, Frank W; Laham, Roger; Jiang, Xuejun; Gu, Wei Wang; Wu, Tim

2014-06-01

316

Marine omega-3 fatty acids prevent myocardial insulin resistance and metabolic remodeling as induced experimentally by high insulin exposure.  

PubMed

Insulin resistance is an important risk factor for the development of several cardiac pathologies, thus advocating strategies for restoring insulin sensitivity of the heart in these conditions. Omega-3 polyunsaturated fatty acids (?-3 PUFAs), mainly eicosapentaenoic acid (EPA, C20:5n-3) and docosahexaenoic acid (DHA, C22:6n-3), have been shown to improve insulin sensitivity in insulin-sensitive tissues, but their direct effect on insulin signaling and metabolic parameters in the myocardium has not been reported previously. The aim of this study was therefore to examine the ability of EPA and DHA to prevent insulin resistance in isolated rat cardiomyocytes. Primary rat cardiomyocytes were made insulin resistant by 48 h incubation in high insulin (HI) medium. Parallel incubations were supplemented by 200 ?M EPA or DHA. Addition of EPA or DHA to the medium prevented the induction of insulin resistance in cardiomyocytes by preserving the phosphorylation state of key proteins in the insulin signaling cascade and by preventing persistent relocation of fatty acid transporter CD36 to the sarcolemma. Only cardiomyocytes incubated in the presence of EPA, however, exhibited improvements in glucose and fatty acid uptake and cell shortening. We conclude that ?-3 PUFAs protect metabolic and functional properties of cardiomyocytes subjected to insulin resistance-evoking conditions. PMID:25472960

Franekova, Veronika; Angin, Yeliz; Hoebers, Nicole T H; Coumans, Will A; Simons, Peter J; Glatz, Jan F C; Luiken, Joost J F P; Larsen, Terje S

2015-02-15

317

Valproic Acid Prevents Penile Fibrosis and Erectile Dysfunction in Cavernous Nerve Injured Rats  

PubMed Central

Introduction Bilateral cavernous nerve injury (BCNI) causes profound penile changes such as apoptosis and fibrosis leading to erectile dysfunction (ED). Histone deacetylase (HDAC) has been implicated in chronic fibrotic diseases. Aims This study will characterize the molecular changes in penile HDAC after BCNI and determine if HDAC inhibition can prevent BCNI-induced ED and penile fibrosis. Methods Five groups of rats (8–10 wks, n=10/group) were utilized: 1) sham, 2&3) BCNI 14 and 30 days following injury, and 4&5) BCNI treated with HDAC inhibitor valproic acid (VPA 250mg/kg; 14 and 30 days). All groups underwent cavernous nerve stimulation (CNS) to determine intracavernosal pressure (ICP). Penile HDAC3, HDAC4, fibronectin, and transforming growth factor-?1 (TGF-?1) protein expression (Western blot) were assessed. Trichrome staining and the fractional area of fibrosis were determined in penes from each group. Cavernous smooth muscle content was assessed by immunofluorescence to alpha smooth muscle actin (?-SMA) antibodies. Main Outcome Measures ICP; HDAC3, HDAC4, fibronectin and TGF-?1 protein expression; penile fibrosis; penile ?-SMA content. Results There was a voltage-dependent decline (p<0.05) in ICP to CNS 14 and 30 days after BCNI. Penile HDAC3, HDAC4, and fibronectin were significantly increased (P<0.05) 14 days after BCNI. There was a slight increase in TGF-?1 protein expression after BCNI. Histological analysis showed increased (P<0.05) corporal fibrosis after BCNI at both time points. VPA treatment decreased (P<0.05) penile HDAC3, HDAC4, and fibronectin protein expression as well as corporal fibrosis. There was no change in penile ?-SMA between all groups. Furthermore, VPA-treated BCNI rats had improved erectile responses to CNS (P<0.05). Conclusion HDAC-induced pathological signaling in response to BCNI contributes to penile vascular dysfunction after BCNI. Pharmacological inhibition of HDAC prevents penile fibrosis, normalizes fibronectin expression, and preserves erectile function. The HDAC pathway may represent a suitable target in preventing the progression of ED occurring post-RP. PMID:24636283

Hannan, Johanna L.; Kutlu, Omer; Stopak, Bernard L.; Liu, Xiaopu; Castiglione, Fabio; Hedlund, Petter; Burnett, Arthur L.; Bivalacqua, Trinity J.

2014-01-01

318

Searching for factors associated with resistance to acetylsalicylic acid used for secondary prevention of stroke  

PubMed Central

Introduction The aim of the study was to evaluate the prevalence of resistance to acetylsalicylic acid (ASA), used for secondary prevention of stroke, including the assessment of risk factors associated with the lack of ASA anti-aggregatory action. Material and methods Patients after a transient ischaemic attack (TIA) or ischaemic stroke in the acute (n = 111) and chronic phase (n = 87) were enrolled in the study. The assessment of platelet function was performed by whole blood impedance aggregometry using a multi-channel platelet function analyser (Multiplate). Results A proper response to ASA was found in 121 patients (61.1%) (ASA responders), a partial response to ASA in 59 patients (29.8%) (ASA partial responders), and ASA resistance in 18 patients (9.1%) (ASA non-responders). Acetylsalicylic acid resistance was observed more frequently in the chronic phase. The mean low-density lipoprotein (LDL) concentration was higher in ASA non-responders (p = 0.02). The mean heart rate (p = 0.03) and the mean haematocrit (p = 0.03) were higher in the group of ASA partial responders and ASA non-responders. Angiotensin II receptor antagonists were more often used in the group of ASA partial responders and ASA non-responders (p = 0.04). Diuretics were more rarely used by ASA non-responders, whereas fibrates were more rarely used by ASA partial responders. Conclusions The method enabled the detection of ASA resistance in some patients with cerebrovascular disease. The study revealed some possible risk factors of ASA resistance: long ASA therapy, increased heart rate, higher LDL concentration, and higher haematocrit value. The relationship between the effect of ASA and other medications (angiotensin II receptor blockers, fibrates, diuretics) requires further study. Platelet function monitoring should be considered in patients at a greater risk of ASA resistance.

Pierzcha?a, Krystyna; Niewiadomska, Ewa; Skrzypek, Micha?; Machowska-Majchrzak, Agnieszka

2015-01-01

319

Valproic acid prevents retinal degeneration in a murine model of normal tension glaucoma.  

PubMed

Valproic acid (VPA) is widely used for treatment of epilepsy, mood disorders, migraines and neuropathic pain. It exerts its therapeutic benefits through modulation of multiple mechanisms including regulation of gamma-aminobutyric acid and glutamate neurotransmissions, activation of pro-survival protein kinases and inhibition of histone deacetylase. The evidence for neuroprotective properties associated with VPA is emerging. Herein, we investigated the therapeutic potential of VPA in a mouse model of normal tension glaucoma (NTG). Mice with glutamate/aspartate transporter gene deletion (GLAST KO mice) demonstrate progressive retinal ganglion cell (RGC) loss and optic nerve degeneration without elevated intraocular pressure, and exhibit glaucomatous pathology including glutamate neurotoxicity and oxidative stress in the retina. VPA (300mg/kg) or vehicle (PBS) was administered via intraperitoneal injection in GLAST KO mice daily for 2 weeks from the age of 3 weeks, which coincides with the onset of glaucomatous retinal degeneration. Following completion of the treatment period, the vehicle-treated GLAST KO mouse retina showed significant RGC death. Meanwhile, VPA treatment prevented RGC death and thinning of the inner retinal layer in GLAST KO mice. In addition, in vivo electrophysiological analyses demonstrated that visual impairment observed in vehicle-treated GLAST KO mice was ameliorated with VPA treatment, clearly establishing that VPA beneficially affects both histological and functional aspects of the glaucomatous retina. We found that VPA reduces oxidative stress induced in the GLAST KO retina and stimulates the cell survival signalling pathway associated with extracellular-signal-regulated kinases (ERK). This is the first study to report the neuroprotective effects of VPA in an animal model of NTG. Our findings raise intriguing possibilities that the widely prescribed drug VPA may be a novel candidate for treatment of glaucoma. PMID:25555796

Kimura, Atsuko; Guo, Xiaoli; Noro, Takahiko; Harada, Chikako; Tanaka, Kohichi; Namekata, Kazuhiko; Harada, Takayuki

2015-02-19

320

Nitroarachidonic acid prevents NADPH oxidase assembly and superoxide radical production in activated macrophages  

PubMed Central

Nitration of arachidonic acid (AA) to nitroarachidonic acid (AANO2) leads to anti-inflammatory intracellular activities during macrophage activation. However, less is known about the capacity of AANO2 to regulate the production of reactive oxygen species (ROS) under pro-inflammatory conditions. One of the immediate responses upon macrophage activation involves the production of superoxide radical (O2·?), due to the NADPH dependent univalent reduction of oxygen to O2·? by the phagocytic NADPH-oxidase isoform (NOX2), being the activity of NOX2 the main source of O2·? in monocytes/macrophages. Since NOX2 and AA pathways are connected, we propose that AANO2can modulate macrophage activation by inhibiting O2·? formation by NOX2. When macrophages were activated in the presence of AANO2, a significant inhibition of NOX2 activity was observed as evaluated by cytochrome c reduction, luminol chemiluminescence, Amplex Red fluorescence and flow cytometry; this process also occurs in physiological mimic conditions within the phagosomes. AANO2 decreased O2·? production in a dose-(IC50= 4.1 ± 1.8 ?M AANO2) and time-dependent manner. The observed inhibition was not due to a decreased phosphorylation of the cytosolic subunits (e.g. p40phox and p47phox), as analyzed by immunoprecipitation and western blot. However, a reduction of the migration to the membrane of p47phox was obtained suggesting that the protective actions involve the prevention of the correct assembly of the active enzyme in the membrane. Finally, the observed in vitro effects were confirmed in an in vivo inflammatory model, where subcutaneous injection of AANO2 was able to decrease NOX2 activity in macrophages from thioglycolate treated mice. PMID:23318789

González-Perilli, Lucía; Álvarez, María Noel; Prolo, Carolina; Radi, Rafael; Rubbo, Homero; Trostchansky, Andrés

2013-01-01

321

Calcium mobilisation and CCK secretion induced by modified fatty acids and latex microspheres reveal dual receptor mechanisms for lipid stimulation of STC-1 cells.  

PubMed

How fatty acids stimulate enteroendocrine cells to release cholecystokinin (CCK) is largely unknown. Recently, we proposed that the murine enteroendocrine cell line, STC-1, responds to insoluble fatty acid aggregates rather than fatty acid monomers in solution. This hypothesis led to two testable predictions. First, other insoluble particles of similar size but unrelated to fatty acid may be able to stimulate STC-1 cells in a similar fashion to dodecanoic acid and second, fatty acid sensing in STC-1 cells should be fairly insensitive to chemical modifications of the fatty acid as long as these modifications do not greatly alter the ability of the molecule to form insoluble aggregates. We used several analogues of dodecanoic acid and several varieties of latex microsphere (varying in size and surface charge) to see whether the predictions of our model hold. We found that while there was at least one latex microsphere that could induce CCK secretion and calcium mobilisation in STC-1 cells, there was a very poor correlation between the presence of insoluble aggregates and a cellular response. Instead the most important property, determining the potency of fatty acid analogues as stimulants of CCK secretion, was their amphipathicity. Removal of either the polar head or lipophilic tail completely abolished the ability of a given fatty acid analogue to stimulate STC-1 cells. These data suggested that while fatty acids can stimulate cells as aggregates, they may also be acting in monomeric form with the oil:water partitioning coefficient playing a crucial role. We finally resolved this issue with the observation that the sulfate ion greatly altered the response of STC-1 cells to monomeric dodecanoic acid. In the presence of sulfate, STC-1 cells will only respond to dodecanoic acid aggregates whereas when sulfate is replaced with chloride the cells clearly respond to dodecanoic acid monomers which are completely in solution. In summary, we propose that dodecanoic acid can stimulate STC-1 cells via two separate pathways one involving fatty acid monomers in solution and one involving fatty acid aggregates. Which pathway dominates depends on the presence of sulfate in the extracellular medium. PMID:14555726

Kazmi, S; Sidhu, S S; Donohoe, T J; Wickham, M; Jones, M N; Thompson, D G; Case, R M; Benson, R S P

2003-12-15

322

Resveratrol prevents social deficits in animal model of autism induced by valproic acid.  

PubMed

Autism spectrum disorders (ASD) involve a complex interplay of both genetic and environmental risk factors, such as prenatal exposure to valproic acid (VPA). Considering the neuroprotective, antioxidant and anti-inflammatory effects of resveratrol (RSV), we investigated the influence of prenatal RSV treatment on social behaviors of a rodent model of autism induced by prenatal exposure to VPA. In the three-chambered apparatus test, the VPA group showed a reduced place preference conditioned by conspecific and no preference between exploring a wire-cage or a rat enclosed inside a wire cage, revealing sociability impairments. Prenatal administration of RSV prevented the VPA-induced social impairments evaluated in this study. A bioinformatics analysis was used to discard possible molecular interactions between VPA and RSV during administration. The interaction energy between RSV and VPA is weak and highly unstable, suggesting cellular effects instead of a single chemical process. In summary, the present study highlights a promising experimental strategy to evaluate new molecular targets possibly involved in the etiology of autism and developmental alterations implicated in neural and behavioral impairments in ASD. PMID:25263788

Bambini-Junior, Victorio; Zanatta, Geancarlo; Della Flora Nunes, Gustavo; Mueller de Melo, Gabriela; Michels, Marcus; Fontes-Dutra, Mellanie; Nogueira Freire, Valder; Riesgo, Rudimar; Gottfried, Carmem

2014-11-01

323

Syringic Acid Extracted from Herba dendrobii Prevents Diabetic Cataract Pathogenesis by Inhibiting Aldose Reductase Activity  

PubMed Central

Objective. Effects of Syringic acid (SA) extracted from dendrobii on diabetic cataract (DC) pathogenesis were explored. Methods. Both in vitro and in vivo DC lens models were established using D-gal, and proliferation of HLEC exposed to SA was determined by MMT assay. After 60-day treatment with SA, rat lens transparency was observed by anatomical microscopy using a slit lamp. SA protein targets were extracted and isolated using 2-DE and MALDI TOF/TOF. AR gene expression was investigated using qRT-PCR. Interaction sites and binding characteristics were determined by molecule-docking techniques and dynamic models. Results. Targeting AR, SA provided protection from D-gal-induced damage by consistently maintaining lens transparency and delaying lens turbidity development. Inhibition of AR gene expression by SA was confirmed by qRT-PCR. IC50 of SA for inhibition of AR activity was 213.17??g/mL. AR-SA binding sites were Trp111, His110, Tyr48, Trp20, Trp79, Leu300, and Phe122. The main binding modes involved hydrophobic interactions and hydrogen bonding. The stoichiometric ratio of non-covalent bonding between SA and AR was 1.0 to 13.3. Conclusion. SA acts to prevent DC in rat lenses by inhibiting AR activity and gene expression, which has potential to be developed into a novel drug for therapeutic management of DC. PMID:23365598

Wei, Xiaoyong; Chen, Dan; Yi, Yanchun; Qi, Hui; Gao, Xinxin; Fang, Hua; Gu, Qiong; Wang, Ling; Gu, Lianquan

2012-01-01

324

Syringic Acid Extracted from Herba dendrobii Prevents Diabetic Cataract Pathogenesis by Inhibiting Aldose Reductase Activity.  

PubMed

Objective. Effects of Syringic acid (SA) extracted from dendrobii on diabetic cataract (DC) pathogenesis were explored. Methods. Both in vitro and in vivo DC lens models were established using D-gal, and proliferation of HLEC exposed to SA was determined by MMT assay. After 60-day treatment with SA, rat lens transparency was observed by anatomical microscopy using a slit lamp. SA protein targets were extracted and isolated using 2-DE and MALDI TOF/TOF. AR gene expression was investigated using qRT-PCR. Interaction sites and binding characteristics were determined by molecule-docking techniques and dynamic models. Results. Targeting AR, SA provided protection from D-gal-induced damage by consistently maintaining lens transparency and delaying lens turbidity development. Inhibition of AR gene expression by SA was confirmed by qRT-PCR. IC(50) of SA for inhibition of AR activity was 213.17??g/mL. AR-SA binding sites were Trp111, His110, Tyr48, Trp20, Trp79, Leu300, and Phe122. The main binding modes involved hydrophobic interactions and hydrogen bonding. The stoichiometric ratio of non-covalent bonding between SA and AR was 1.0 to 13.3. Conclusion. SA acts to prevent DC in rat lenses by inhibiting AR activity and gene expression, which has potential to be developed into a novel drug for therapeutic management of DC. PMID:23365598

Wei, Xiaoyong; Chen, Dan; Yi, Yanchun; Qi, Hui; Gao, Xinxin; Fang, Hua; Gu, Qiong; Wang, Ling; Gu, Lianquan

2012-01-01

325

Betulinic acid prevents alcohol-induced liver damage by improving the antioxidant system in mice  

PubMed Central

Betulinic acid (BA), a pentacyclic lupane-type triterpene, has a wide range of bioactivities. The main objective of this work was to evaluate the hepatoprotective activity of BA and the potential mechanism underlying the ability of this compound to prevent liver damage induced by alcohol in vivo. Mice were given oral doses of BA (0.25, 0.5, and 1.0 mg/kg) daily for 14 days, and induced liver injury by feeding 50% alcohol orally at the dosage of 10 ml/kg after 1 h last administration of BA. BA pretreatment significantly reduced the serum levels of alanine transaminase, aspartate transaminase, total cholesterol, and triacylglycerides in a dose-dependent manner in the mice administered alcohol. Hepatic levels of glutathione, superoxide dismutase, glutathione peroxidase, and catalase were remarkably increased, while malondialdehyde contents and microvesicular steatosis in the liver were decreased by BA in a dose-dependent manner after alcohol-induced liver injury. These findings suggest that the mechanism underlying the hepatoprotective effects of BA might be due to increased antioxidant capacity, mainly through improvement of the tissue redox system, maintenance of the antioxidant system, and decreased lipid peroxidation in the liver. PMID:24378582

Xia, Wei; Wu, Jianping; Yuan, Liyun; Wu, Jing; Tu, Di; Fang, Jun

2014-01-01

326

Calcification prevention tablets  

NASA Technical Reports Server (NTRS)

Citric acid tablets, which slowly release citric acid when flushed with water, are under development by the Navy for calcification prevention. The citric acid dissolves calcium carbonate deposits and chelates the calcium. For use in urinals, a dispenser is not required because the tablets are non-toxic and safe to handle. The tablets are placed in the bottom of the urinal, and are consumed in several hundred flushes (the release rate can be tailored by adjusting the formulation). All of the ingredients are environmentally biodegradable. Mass production of the tablets on commercial tableting machines was demonstrated. The tablets are inexpensive (about 75 cents apiece). Incidences of clogged pipes and urinals were greatly decreased in long term shipboard tests. The corrosion rate of sewage collection pipe (90/10 Cu/Ni) in citric acid solution in the laboratory is several mils per year at conditions typically found in traps under the urinals. The only shipboard corrosion seen to date is of the yellow brass urinal tail pieces. While this is acceptable, the search for a nontoxic corrosion inhibitor is underway. The shelf life of the tablets is at least one year if stored at 50 percent relative humidity, and longer if stored in sealed plastic buckets.

Lindsay, Geoffrey A.; Hasting, Michael A.; Gustavson, Michael A.

1991-01-01

327

The influences of poly(lactic-co-glycolic acid) (PLGA) coating on the biodegradability, bioactivity, and biocompatibility of calcium silicate bioceramics  

Microsoft Academic Search

Calcium silicate (CaSiO3) bioceramics and polyesters have complementary qualities as potential bone substituted materials. In this study, sintered\\u000a CaSiO3 bioceramics were prepared and coated with poly(lactic-co-glycolic acid) (PLGA), and the influences of the PLGA coating on\\u000a the degradation, hydrophilicity, bioactivity, and biocompatibility of CaSiO3 ceramics were investigated. The results showed that the degradation rate was reduced, while hydrophilicity was decreased

Lang Zhao; Kaili Lin; Meili Zhang; Chengdong Xiong; Yihong Bao; Xiubing Pang; Jiang Chang

2011-01-01

328

S-acylation-dependent association of the calcium sensor CBL2 with the vacuolar membrane is essential for proper abscisic acid responses  

PubMed Central

Calcineurin B-like (CBL) proteins contribute to decoding calcium signals by interacting with CBL-interacting protein kinases (CIPKs). Currently, there is still very little information about the function and specific targeting mechanisms of CBL proteins that are localized at the vacuolar membrane. In this study, we focus on CBL2, an abundant vacuolar membrane-localized calcium sensor of unknown function from Arabidopsis thaliana. We show that vacuolar targeting of CBL2 is specifically brought about by S-acylation of three cysteine residues in its N-terminus and that CBL2 S-acylation and targeting occur by a Brefeldin A-insensitive pathway. Loss of CBL2 function renders plants hypersensitive to the phytohormone abscisic acid (ABA) during seed germination and only fully S-acylated and properly vacuolar-targeted CBL2 proteins can complement this mutant phenotype. These findings define an S-acylation-dependent vacuolar membrane targeting pathway for proteins and uncover a crucial role of vacuolar calcium sensors in ABA responses. PMID:22547024

Batisti?, Oliver; Rehers, Marion; Akerman, Amir; Schlücking, Kathrin; Steinhorst, Leonie; Yalovsky, Shaul; Kudla, Jörg

2012-01-01

329

Cilnidipine, an L/N-type calcium channel blocker prevents acquisition and expression of ethanol-induced locomotor sensitization in mice.  

PubMed

Several evidences indicated the involvement of L- and N-type calcium channels in behavioral effects of drugs of abuse, including ethanol. Calcium channels are implicated in ethanol-induced behaviors and neurochemical responses. Calcium channel antagonists block the psychostimulants induced behavioral sensitization. Recently, it is demonstrated that L-, N- and T-type calcium channel blockers attenuate the acute locomotor stimulant effects of ethanol. However, no evidence indicated the role of calcium channels in ethanol-induced psychomotor sensitization. Therefore, present study evaluated the influence of cilnidipine, an L/N-type calcium channel blocker on acquisition and expression of ethanol-induced locomotor sensitization. The results revealed that cilnidipine (0.1 and 1.0?g/mouse, i.c.v.) attenuates the expression of sensitization to locomotor stimulant effect of ethanol (2.0g/kg, i.p.), whereas pre- treatment of cilnidipine (0.1 and 1.0?g/mouse, i.c.v.) during development of sensitization blocks acquisition and attenuates expression of sensitization to locomotor stimulant effect of ethanol. Cilnidipine per se did not influence locomotor activity in tested doses. Further, cilnidipine had no influence on effect of ethanol on rotarod performance. These results support the hypothesis that neuroadaptive changes in calcium channels participate in the acquisition and the expression of ethanol-induced locomotor sensitization. PMID:22402189

Bhutada, Pravinkumar; Mundhada, Yogita; Patil, Jayshree; Rahigude, Anand; Zambare, Krushna; Deshmukh, Prashant; Tanwar, Dhanshree; Jain, Kishor

2012-04-11

330

21 CFR 184.1207 - Calcium lactate.  

Code of Federal Regulations, 2011 CFR

...O, where x is any integer up to 5, CAS Reg. No. 814-80-2) is prepared commercially by the neutralization of lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient meets the specifications of the Food...

2011-04-01

331

21 CFR 184.1207 - Calcium lactate.  

Code of Federal Regulations, 2010 CFR

...O, where x is any integer up to 5, CAS Reg. No. 814-80-2) is prepared commercially by the neutralization of lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient meets the specifications of the Food...

2010-04-01

332

21 CFR 184.1207 - Calcium lactate.  

Code of Federal Regulations, 2014 CFR

...O, where x is any integer up to 5, CAS Reg. No. 814-80-2) is prepared commercially by the neutralization of lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient meets the specifications of the Food...

2014-04-01

333

21 CFR 184.1207 - Calcium lactate.  

Code of Federal Regulations, 2012 CFR

...O, where x is any integer up to 5, CAS Reg. No. 814-80-2) is prepared commercially by the neutralization of lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient meets the specifications of the Food...

2012-04-01

334

21 CFR 184.1207 - Calcium lactate.  

Code of Federal Regulations, 2013 CFR

...O, where x is any integer up to 5, CAS Reg. No. 814-80-2) is prepared commercially by the neutralization of lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient meets the specifications of the Food...

2013-04-01

335

Inhibition of Calcineurin-mediated Endocytosis and ?-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid (AMPA) Receptors Prevents Amyloid ? Oligomer-induced Synaptic Disruption  

PubMed Central

Synaptic degeneration, including impairment of synaptic plasticity and loss of synapses, is an important feature of Alzheimer disease pathogenesis. Increasing evidence suggests that these degenerative synaptic changes are associated with an accumulation of soluble oligomeric assemblies of amyloid ? (A?) known as ADDLs. In primary hippocampal cultures ADDLs bind to a subpopulation of neurons. However the molecular basis of this cell type-selective interaction is not understood. Here, using siRNA screening technology, we identified ?-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunits and calcineurin as candidate genes potentially involved in ADDL-neuron interactions. Immunocolocalization experiments confirmed that ADDL binding occurs in dendritic spines that express surface AMPA receptors, particularly the calcium-impermeable type II AMPA receptor subunit (GluR2). Pharmacological removal of the surface AMPA receptors or inhibition of AMPA receptors with antagonists reduces ADDL binding. Furthermore, using co-immunoprecipitation and photoreactive amino acid cross-linking, we found that ADDLs interact preferentially with GluR2-containing complexes. We demonstrate that calcineurin mediates an endocytotic process that is responsible for the rapid internalization of bound ADDLs along with surface AMPA receptor subunits, which then both colocalize with cpg2, a molecule localized specifically at the postsynaptic endocytic zone of excitatory synapses that plays an important role in activity-dependent glutamate receptor endocytosis. Both AMPA receptor and calcineurin inhibitors prevent oligomer-induced surface AMPAR and spine loss. These results support a model of disease pathogenesis in which A? oligomers interact selectively with neurotransmission pathways at excitatory synapses, resulting in synaptic loss via facilitated endocytosis. Validation of this model in human disease would identify therapeutic targets for Alzheimer disease. PMID:20032460

Zhao, Wei-Qin; Santini, Francesca; Breese, Robert; Ross, Dave; Zhang, Xiaohua Douglas; Stone, David J.; Ferrer, Marc; Townsend, Matthew; Wolfe, Abigail L.; Seager, Matthew A.; Kinney, Gene G.; Shughrue, Paul J.; Ray, William J.

2010-01-01

336

Chitosan-calcium carbonate composites by a biomimetic process  

Microsoft Academic Search

The crystal growth of calcium carbonate on a chitosan substrate was achieved using a supersaturated calcium carbonate solution, by using various additives, such as 6-aminocaproic acid (6AA) and polyacrylic acid (PAA). Polyacrylic acid modified the chitosan-film surface and promoted the nucleation of calcium carbonate crystals. In the absence of polyacrylic acid, sporadic nucleation and crystallization was observed via optical microscopy.

Sukun Zhang; K. E. Gonsalves

1995-01-01

337

Antinociceptive effect of clavulanic acid and its preventive activity against development of morphine tolerance and dependence in animal models  

PubMed Central

Glutamate has a key role in pain perception and also development of tolerance and dependence to morphine. It has been reported that clavulanic acid affects glutamatergic transmission via activation of glutamate transporter. Therefore the present study was aimed to evaluate the possible antinociceptive effect of clavulanic acid and its preventive activity against development of morphine tolerance and dependence in animal models. Male Swiss mice (25-30 g) were used in this study. Acetic acid-induced writhing, formalin test and hot plate method were used to assess the antinociceptive effect of clavulanic acid. Morphine (30 mg/kg, s.c.) was administered to the mice two times a day (8 AM and 4 PM) for 3 days in order to produce tolerance. To develop morphine dependence, morphine sulfate (50, 50 and 75 mg/kg) was injected at 8 and 12 AM and 16 PM respectively and for 3 consecutive days. Naloxone (5 mg/kg, i.p) was used to induce morphine withdrawal syndrome and the number of jumps and presence of ptosis, piloerection, tremor, sniffing and diarrhea were recorded and compared with control group. Clavulanic acid at doses of 10, 20 and 40 mg/kg inhibited abdominal constriction and licking behavior of acetic acid and formalin-induced pain respectively. Clavulanic acid was not able to show any antinociception in hot plate model and could not prevent development of tolerance and dependence to morphine. Clavulanic acid has considerable antinociceptive activity and further studies are needed to clarify its exact mechanism. PMID:25657803

Hajhashemi, V.; Dehdashti, Kh.

2014-01-01

338

Membrane Omega-3 Fatty Acid Deficiency as a Preventable Risk Factor for Comorbid Coronary Heart Disease in Major Depressive Disorder  

PubMed Central

Major depression disorder (MDD) significantly increases the risk for coronary heart disease (CHD) which is a leading cause of mortality in patients with MDD. Moreover, depression is frequently observed in a subset of patients following acute coronary syndrome (ACS) and increases risk for mortality. Here evidence implicating omega-3 (n-3) fatty acid deficiency in the pathoaetiology of CHD and MDD is reviewed, and the hypothesis that n-3 fatty acid deficiency is a preventable risk factor for CHD comorbidity in MDD patients is evaluated. This hypothesis is supported by cross-national and cross-sectional epidemiological surveys finding an inverse correlation between n-3 fatty acid status and prevalence rates of both CHD and MDD, prospective studies finding that lower dietary or membrane EPA+DHA levels increase risk for both MDD and CHD, case-control studies finding that the n-3 fatty acid status of MDD patients places them at high risk for emergent CHD morbidity and mortality, meta-analyses of controlled n-3 fatty acid intervention studies finding significant advantage over placebo for reducing depression symptom severity in MDD patients, and for secondary prevention of cardiac events in CHD patients, findings that n-3 fatty acid status is inversely correlated with other documented CHD risk factors, and patients diagnosed with MDD after ACS exhibit significantly lower n-3 fatty acid status compared with nondepressed ACS patients. This body of evidence provides strong support for future studies to evaluate the effects of increasing dietary n-3 fatty acid status on CHD comorbidity and mortality in MDD patients. PMID:19936106

McNamara, Robert K.

2009-01-01

339

Role of the Conjugated Linoleic Acid in the Prevention of Cancer  

Microsoft Academic Search

There are multiple lines of evidence that a variety of natural fatty acids are effective in health promotion. Among these fatty acids, conjugated linoleic acid (CLA)—a collective term referring to a mixture of positional and geometric isomers of linoleic acid (LA, cis-9, cis-12-octadecadienoic acid)—is currently under intensive investigation due to its health-promotion potential. The antitumor activity of CLA is of

KI WON LEE; HYONG JOO LEE; HONG YON CHO; YOUNG JUN KIM

2005-01-01

340

40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...  

Code of Federal Regulations, 2012 CFR

...acetate, calcium magnesium potassium sodium salt. 721.2076 Section 721.2076 Protection...acetate, calcium magnesium potassium sodium salt. (a) Chemical substance and significant...acetate, calcium magnesium potassium sodium salt (PMN P-00-7; CAS...

2012-07-01

341

40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...  

Code of Federal Regulations, 2010 CFR

...acetate, calcium magnesium potassium sodium salt. 721.2076 Section 721.2076 Protection...acetate, calcium magnesium potassium sodium salt. (a) Chemical substance and significant...acetate, calcium magnesium potassium sodium salt (PMN P-00-7; CAS...

2010-07-01

342

Updated estimates of neural tube defects prevented by mandatory folic Acid fortification - United States, 1995-2011.  

PubMed

In 1992, the U.S. Public Health Service recommended that all women capable of becoming pregnant consume 400 µg of folic acid daily to prevent neural tube defects (NTDs). NTDs are major birth defects of the brain and spine that occur early in pregnancy as a result of improper closure of the embryonic neural tube, which can lead to death or varying degrees of disability. The two most common NTDs are anencephaly and spina bifida. Beginning in 1998, the United States mandated fortification of enriched cereal grain products with 140 µg of folic acid per 100 g. Immediately after mandatory fortification, the birth prevalence of NTD cases declined. Fortification was estimated to avert approximately 1,000 NTD-affected pregnancies annually. To provide updated estimates of the birth prevalence of NTDs in the period after introduction of mandatory folic acid fortification (i.e., the post-fortification period), data from 19 population-based birth defects surveillance programs in the United States, covering the years 1999-2011, were examined. After the initial decrease, NTD birth prevalence during the post-fortification period has remained relatively stable. The number of births occurring annually without NTDs that would otherwise have been affected is approximately 1,326 (95% confidence interval = 1,122-1,531). Mandatory folic acid fortification remains an effective public health intervention. There remain opportunities for prevention among women with lower folic acid intakes, especially among Hispanic women, to further reduce the prevalence of NTDs in the United States. PMID:25590678

Williams, Jennifer; Mai, Cara T; Mulinare, Joe; Isenburg, Jennifer; Flood, Timothy J; Ethen, Mary; Frohnert, Barbara; Kirby, Russell S

2015-01-16

343

Alpha-lipoic Acid prevents endotoxic shock and multiple organ dysfunction syndrome induced by endotoxemia in rats.  

PubMed

Alpha-lipoic acid (ALA), a naturally occurring disulfide derivative of octanoic acid, serves as a strong antioxidant and has been reported to possess anti-inflammatory effects. The aim of the present study is to investigate the preventive and therapeutic effects of ALA on multiple organ dysfunction syndrome (MODS) caused by endotoxemia in rats. Male Wistar rats were intravenously infused with lipopolysaccharide (LPS) (10 mg/kg) to induce endotoxemia. Alpha-lipoic acid 10, 20, or 40 mg/kg was administered intravenously 60 min before (pretreatment) LPS challenge, and ALA 40 mg/kg was administered intravenously 30 min after (posttreatment) LPS challenge. Pretreatment and posttreatment with ALA significantly improved the deleterious hemodynamic changes 8 h after LPS challenge, including hypotension and bradycardia. Alpha-lipoic acid reduced the plasma levels of glutamic pyruvic transaminase, blood urea nitrogen, lactate dehydrogenase, tumor necrosis factor-?, nitric oxide metabolites, and thrombin-antithrombin complex, which increased markedly after LPS challenge. The induction of inducible nitric oxide synthase both in the liver and the lung and vascular superoxide anion production were also significantly suppressed by ALA. Moreover, ALA significantly attenuated LPS-induced caspase-3 activation in cardiomyocytes and improved survival rate. In conclusion, ALA effectively attenuated LPS-induced acute inflammatory response and improved MODS. The antioxidant and anti-inflammatory effects of ALA may contribute to these beneficial effects. Alpha-lipoic acid might be considered as a novel therapeutic strategy in the prevention of sepsis-induced MODS and inflammatory vascular diseases. PMID:25514429

Shen, Hsin-Hsueh; Lam, Kwok-Keung; Cheng, Pao-Yun; Kung, Ching-Wen; Chen, Shu-Ying; Lin, Pei-Chiang; Chung, Ming-Ting; Lee, Yen-Mei

2015-04-01

344

Oral administration of ?-aminobutyric acid and ?-oryzanol prevents stress-induced hypoadiponectinemia.  

PubMed

Metabolic syndrome is a cluster of risk factors including insulin resistance and type 2 diabetes and is found to associate partly with chronic stress at work in human. Adiponectin circulates in mammal blood mainly as a low molecular weight (LMW) trimer, hexamer, and a high molecular weight (HMW) multimers. Low circulating levels of adiponectin are related to metabolic syndrome. We have then investigated the influence of immobilization stress on plasma adiponectin concentrations in mice. Relative LMW and HMW adiponectin levels were markedly reduced by immobilization stress (0.66±0.07 and 0.59±0.06 after 102 h, respectively), significantly different from the control values (p<0.01 and 0.05, respectively). ?-Aminobutyric acid (GABA) and ?-oryzanol abundantly contained in germinated brown rice have some physiological functions. We further investigated the effect of GABA, ?-oryzanol, GABA plus ?-oryzanol on adiponectin levels in mice subjected to immobilization stress. GABA and ?-oryzanol significantly increased the relative LMW and HMW adiponectin levels under immobilization stress (1.10±0.11 and 0.99±0.19 after 102 h, respectively, for GABA; 1.08±0.17 and 1.15±0.17 after 102 h, respectively, for ?-oryzanol). Additionally, the co-administration of GABA and ?-oryzanol also increased both relative LMW and HMW adiponectin levels (1.02±0.07 and 0.99±0.10 after 102 h, respectively) and was effective in an earlier phase from 30 to 54 h. The results indicate that the co-administration of GABA and ?-oryzanol might be effective in preventing stress-induced hypoadiponectinemia in mice and be also a promising tool for improving metabolic syndrome aggravated by chronic stress. PMID:21316207

Ohara, Kazuyuki; Kiyotani, Yuka; Uchida, Asako; Nagasaka, Reiko; Maehara, Hiroyuki; Kanemoto, Shigeharu; Hori, Masatoshi; Ushio, Hideki

2011-06-15

345

Structured triacylglycerol containing behenic and oleic acids suppresses triacylglycerol absorption and prevents obesity in rats  

PubMed Central

Background Dietary 1(3)-behenoyl-2,3(1)-dioleoyl-rac-glycerol (BOO) has been reported to inhibit pancreatic lipase activity in vitro and suppress postprandial hypertriacylglycerolemia in humans. In the present study, the anti-obesity activities of BOO and its inhibitory effects on lymphatic triacylglycerol (TAG) absorption were investigated in rats. Methods In Experiment 1, rats were fed either BOO or soybean oil (SO) diet for 6 weeks. In the BOO diet, 20% of SO was replaced with an experimental oil rich in BOO. In Experiments 2 and 3, rats cannulated in the thoracic duct were administered an emulsions containing trioleoylglycerol (OOO) or an oil mixture (OOO:BOO, 9:1). Tri[1-14C]oleoylglycerol (14C-OOO) was added to the emulsions administered in Experiment 3. Results No observable differences were detected in food intake or body weight gain between the BOO and SO groups in Experiment 1. Plasma and liver TAG concentrations and visceral fat weights were significantly lower in the BOO group than in the SO group. The apparent absorption rate of fat was significantly lower in the BOO group than in the SO group. In Experiment 2, the lymphatic recovery of oleic and behenic acids was significantly lower at 5 and 6 h after BOO administration than after OOO administration. In Experiment 3, the lymphatic recovery of 14C-OOO was significantly lower at 5 and 6 h after BOO administration than after OOO administration. Conclusions These results suggest that BOO prevents deposition of visceral fat and hepatic TAG by lowering and delaying intestinal absorption of TAG. PMID:20653972

2010-01-01

346

Multi-element analysis of milk by ICP-oa-TOF-MS after precipitation of calcium and proteins by oxalic and nitric acid.  

PubMed

In this work a simple technique employing oxalic and nitric acid to cow's milk samples prior to analysis by inductively coupled plasma orthogonal acceleration time-of-flight mass spectrometry (ICP-oa-TOF-MS) was introduced. After the precipitation of calcium and proteins via oxalic and nitric acid, respectively, the resulting liquid phase was aspirated with a concentric glass nebulizer for ICP-TOF-MS determination of trace elements. Precipitation of proteins is essential for better separation of solid and liquid phase of modified samples. Separation of calcium as a precipitated non-soluble oxalate enables the elimination of spectral interferences originating from different calcium containing species like (40)Ca(35)Cl(+), (40)Ca(37)Cl(+), (43)Ca(16)O(+), (40)Ca(18)O(+), (44)Ca(16)O(+), (43)Ca(16)O(1)H(+) onto the determination of As, Se, Co and Ni whose assay is more difficult when using conventional quadrupole instruments. High detection capability is further an advantage as the approach enables the analysis without dilution. The methodology may serve, in addition, for a fast and sensitive determination of some other elements. After that, direct, reliable and simultaneous determination of 16 elements (Li, Be, B, V, Cr, Mn, Ni, Co, Ga, As, Se, Mo, Sn, Sb, Cs, Tl) at trace and ultra-trace levels in milk can be performed under optimum instrumental conditions and by using Rh as an internal standard. Accuracy and precision was assessed by measuring NCS ZC73015 milk powder control standard, yielding results in agreement with certified values and RSD <10%. The accuracy was also checked by comparison of the results of the proposed method with those found by a method based on a microwave-assisted digestion of real samples. PMID:23598096

Husáková, Lenka; Urbanová, Iva; Šrámková, Jitka; Kone?ná, Michaela; Bohuslavová, Jana

2013-03-15

347

Folate Deficiency and Folic Acid Supplementation: The Prevention of Neural-Tube Defects and Congenital Heart Defects  

PubMed Central

Diet, particularly vitamin deficiency, is associated with the risk of birth defects. The aim of this review paper is to show the characteristics of common and severe neural-tube defects together with congenital heart defects (CHD) as vitamin deficiencies play a role in their origin. The findings of the Hungarian intervention (randomized double-blind and cohort controlled) trials indicated that periconceptional folic acid (FA)-containing multivitamin supplementation prevented the major proportion (about 90%) of neural-tube defects (NTD) as well as a certain proportion (about 40%) of congenital heart defects. Finally the benefits and drawbacks of three main practical applications of folic acid/multivitamin treatment such as (i) dietary intake; (ii) periconceptional supplementation; and (iii) flour fortification are discussed. The conclusion arrived at is indeed confirmation of Benjamin Franklin’s statement: “An ounce of prevention is better than a pound of care”. PMID:24284617

Czeizel, Andrew E.; Dudás, Istvan; Vereczkey, Attila; Bánhidy, Ferenc

2013-01-01

348

Enhanced drug encapsulation and extended release profiles of calcium-alginate nanoparticles by using tannic acid as a bridging cross-linking agent.  

PubMed

Abstract Calcium alginate nanoparticles (NPs) suffer from sub-optimal stability in bio-relevant media leading to low drug encapsulation efficiency and uncontrolled release profiles. To sort out these drawbacks, a novel approach is proposed herein based on introducing tannic acid into these NPs to act as a bridging cross-linking aid agent. Calcium-alginate NPs were prepared by the ionotropic gelation method and loaded with diltiazem hydrochloride as a model drug. These NPs were characterized in terms of particle size, zeta potential, and morphology, and results were explained in accordance with Fourier-transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). The incorporation of tannic acid led to more than four folds increase in drug encapsulation efficiency (i.e. from 15.3% to 69.5%) and reduced burst drug release from 44% to around 10% within the first 30?min. These findings suggest the possibility of improving the properties of Ca-alginate NPs by incorporating cross-linking aid agents under mild conditions. PMID:25413187

Abulateefeh, Samer R; Taha, Mutasem O

2014-11-21

349

Phase III Randomized, Placebo-Controlled, Double-Blind Study of Intravenous Calcium and Magnesium to Prevent Oxaliplatin-Induced Sensory Neurotoxicity (N08CB/Alliance)  

PubMed Central

Purpose Cumulative neurotoxicity is a prominent toxicity of oxaliplatin-based therapy. Intravenous calcium and magnesium have been extensively used to reduce oxaliplatin-induced neurotoxicity. This trial was designed to definitively test whether calcium/magnesium decreases oxaliplatin-related neurotoxicity. Patients and Methods In all, 353 patients with colon cancer undergoing adjuvant therapy with FOLFOX (fluorouracil, leucovorin, and oxaliplatin) were randomly assigned to intravenous calcium/magnesium before and after oxaliplatin, a placebo before and after, or calcium/magnesium before and placebo after. The primary end point was cumulative neurotoxicity measured by the sensory scale of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Chemotherapy-Induced Peripheral Neuropathy 20 tool. Results There were no statistically significant neuropathy differences among the study arms as measured by the primary end point or additional measures of neuropathy, including clinician-determined measurement of the time to grade 2 neuropathy by using the National Cancer Institute Common Terminology Criteria for Adverse Events scale or an oxaliplatin-specific neuropathy scale. In addition, calcium/magnesium did not substantially decrease oxaliplatin-induced acute neuropathy. Conclusion This study does not support using calcium/magnesium to protect against oxaliplatin-induced neurotoxicity. PMID:24297951

Loprinzi, Charles L.; Qin, Rui; Dakhil, Shaker R.; Fehrenbacher, Louis; Flynn, Kathleen A.; Atherton, Pamela; Seisler, Drew; Qamar, Rubina; Lewis, Grant C.; Grothey, Axel

2014-01-01

350

Preventing Acid Mine Drainage with an Elevated Water Table: Long-Term Column Experiments and Parameter Analysis  

Microsoft Academic Search

The elevated water table (EWT) technique for preventing acid mine drainage (AMD) was tested using instrumented laboratory\\u000a columns containing reactive tailings from the Louvicourt and Sigma mines, Abitibi, Quebec. The tests were performed in short\\u000a (0.4 m) and long (1.4–1.7 m) columns over 400–500 days and included periodic surface recharge and subsequent monitoring of\\u000a the leached drainage water. In each column, the water

Mariam Ouangrawa; Michel Aubertin; John W. Molson; Bruno Bussière; Gérald J. Zagury

2010-01-01

351

CORONARY ARTERY CALCIUM IN RELATION TO INITIATION AND CONTINUATION OF CARDIOVASCULAR PREVENTIVE MEDICATIONS: THE MULTI-ETHNIC STUDY OF ATHEROSCLEROSIS (MESA)  

PubMed Central

Background Whether measuring and reporting of coronary artery calcium scores (CACS) might lead to changes in cardiovascular risk management is not established. In this observational study we examined whether high baseline CACS were associated with the initiation as well continuation of new lipid lowering medication (LLM), blood pressure lowering medication (BPLM) and regular aspirin (ASA) use in a multi-ethnic population-based cohort. Methods and Results MESA is a prospective cohort study of 6814 participants free of clinical cardiovascular disease at entry who underwent CAC testing at baseline examination (exam 1). Information on LLM, BPLM and regular ASA usage was also obtained at baseline, and at exams 2 and 3 (average of 1.6 and 3.2 years after baseline respectively). In this study we examined: 1) initiation of these medications at exam 2 among participants not taking these medications at baseline; and 2) continuation of medication use to exam 3 among participants already on medication at baseline. Among MESA participants, initiation of LLM, BPLM and ASA was greater in those with higher CACS After taking into account age, gender, race, MESA site, LDL cholesterol, diabetes mellitus, BMI, smoking status, hypertension, systolic blood pressure, and SES (income, education and health insurance), the risk ratios for medication initiation comparing those with CACS>400 vs. CACS=0 were 1.53 (95% CI: 1.08, 2.15) for LLM, 1.55 (1.10-- 2.17) for BPLM, and 1.32 (1.03–1.69) for ASA initiation, respectively. The risk ratios for medication continuation among those with CAC>400 vs. CACS=0 were 1.10 (95% CI: 1.01–1.20) for LLM, 1.05 (1.02–1.08) for BPLM, and 1.14 (1.04- 1.25) for ASA initiation, respectively. Conclusion CACS>400 was associated with a higher likelihood of initiation and continuation of LLM, BPLM and ASA. The association was weaker for continuation than for initiation of these preventive therapies. PMID:20371760

Nasir, Khurram; McClelland, Robyn L.; Blumenthal, Roger S; Goff, David C; Hoffmann, Udo; Psaty, Bruce M.; Greenland, Philip; Kronmal, Richard A.; Budoff, Matthew J

2015-01-01

352

Calcium requirements for Asian children and adolescents  

Microsoft Academic Search

Calcium is important for bone health. Over the last 15 years, reference calcium intakes in Western countries have been revised upwards for maximizing bone mass at skeletal maturity and for prevention of osteoporotic fractures. Some of these reference figures have also been adopted for use in Asian countries. However, the sci- entific data based on for revising reference calcium intakes

Warren Tak Keung Lee; Ji Jiang

353

Ca 2+ channel blockade prevents lysergic acid diethylamide-induced changes in dopamine and serotonin metabolism  

Microsoft Academic Search

To investigate the effect of a single and multiple administration of lysergic acid diethylamide (LSD) on cerebral metabolism of dopamine and serotonin, male Wistar rats were treated with low and high doses (0.1 and 2.0 mg\\/kg i.p.) of LSD and the levels of dopamine, 3,4-dihydroxyphenylacetic acid, homovanillic acid, 3-methoxytyramine, serotonin and 5-hydroxyindoleacetic acid were assayed by HPLC in the nucleus

Lucyna Antkiewicz-Michaluk; Irena Roma?ska; Jerzy Vetulani

1997-01-01

354

Palmitoleic acid prevents palmitic acid-induced macrophage activation and consequent p38 MAPK-mediated skeletal muscle insulin resistance  

PubMed Central

Obesity and saturated fatty acid (SFA) treatment are both associated with skeletal muscle insulin resistance (IR) and increased macrophage infiltration. However, the relative effects of SFA and unsaturated fatty acid (UFA)-activated macrophages on muscle are unknown. Here, macrophages were treated with palmitic acid, palmitoleic acid or both and the effects of the conditioned medium (CM) on C2C12 myotubes investigated. CM from palmitic acid-treated J774s (palm-mac-CM) impaired insulin signalling and insulin-stimulated glycogen synthesis, reduced Inhibitor ?B? and increased phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase in myotubes. p38 MAPK inhibition or siRNA partially ameliorated these defects, as did addition of tumour necrosis factor-? blocking antibody to the CM. Macrophages incubated with both FAs generated CM that did not induce IR, while palmitoleic acid-mac-CM alone was insulin sensitising. Thus UFAs may improve muscle insulin sensitivity and counteract SFA-mediated IR through an effect on macrophage activation. PMID:24973767

Talbot, Nicola A.; Wheeler-Jones, Caroline P.; Cleasby, Mark E.

2014-01-01

355

Preferential affinity of calcium ions to charged phosphatidic-acid surface from a mixed calcium/barium solution: X-ray reflectivity and fluorescence studies  

E-print Network

X-ray reflectivity and fluorescence near total reflection experiments were performed to examine the affinities of divalent ions ($\\mathrm{Ca^{2+}}$ and $\\mathrm{Ba^{2+}}$) from aqueous solution to a charged phosphatidic-acid (PA) surface. A phospholipid (1,2-Dimyristoyl-sn-Glycero-3-Phosphate, DMPA), spread as a monolayer at the air/water interface, was used to form and control the charge density at the interface. We find that for solutions of the pure salts (i.e., $\\mathrm{CaCl_{2}}$ and $\\mathrm{BaCl_{2}}$), the number of bound ions per DMPA at the interface is saturated at concentrations that exceed $\\mathrm{10^{-3}M}$. For a 1:1 $\\mathrm{Ca^{2+}/Ba^{2+}}$ mixed solutions, we find that the bound $\\mathrm{Ca^{2+}/Ba^{2+}}$ ratio at the interface is 4:1. If the only property determining charge accumulation near PA were the ionic charges, the concentration of mixed $\\mathrm{Ca^{2+}/Ba^{2+}}$ at the interface would equal that of the bulk. Our results show a clear specific affinity of PA for Ca compared to Ba. We provide some discussion on this issues as well as some implications for biological systems. Although our results indicate an excess of counterion charge with respect to the surface charge, that is, charge inversion, the analysis of both reflectivity and fluorescence do not reveal excess of co-ions (namely, $\\mathrm{Cl^{-}}$ or $\\mathrm{I}^{-}$).

Wei Bu; Kevin Flores; Jacob Pleasants; David Vaknin

2009-01-16

356

Synthesis of hydroxyapatite by using calcium carbonate and phosphoric acid in various water-ethanol solvent systems  

Microsoft Academic Search

The purpose of the present study is to synthesize hydroxyapatite by using CaCO3 and H3PO4 in various water-ethanol solvent systems. It was observed from experiments that formation of ammonium phosphate compounds\\u000a hindered the formation of calcium phosphates in ethanol medium. Although the reactivity was better in aqueous medium, the\\u000a carbonate contents of the products obtained were above 8.5%. Best results

Arzu Engin; ?smail Girgin

2009-01-01

357

Black Tea May Be a Prospective Adjunct for Calcium Supplementation to Prevent Early Menopausal Bone Loss in a Rat Model of Osteoporosis  

PubMed Central

The present study was undertaken to find out the ability of black tea extract (BTE) as a suitable alternative of adjunct for calcium supplementation in treating an ovariectomized rat model of early osteoporosis. Female Wistar rats weighing 140–150?g were divided into four groups consisting of six animals in each group: (A) sham-operated control; (B) bilaterally ovariectomized; (C) bilaterally ovariectomized + BTE; (D) bilaterally ovariectomized + 17?-estradiol. Results suggest that BTE could promote intestinal absorption of calcium significantly (P < 0.01 for duodenum and ileum; and P < 0.05 for jejunum). This was found associated with enhanced activities of two relevant intestinal mucosal enzymes alkaline phosphatase (P < 0.01 for duodenum, jejunum, and ileum) and Ca2+ activated ATPase (P < 0.01 for duodenum, jejunum, and ileum). Such BTE-mediated promotion of calcium absorption was coupled with increase in serum estrogen titer (P < 0.01) and recovery of all urinary, bone, and serum osteoporotic marker parameters, including bone histological features. Serum parathyroid hormone level, however, was not altered in these animals (P > 0.05). A comparative study with 17?-estradiol, a well-known adjunct for calcium supplementation, indicated that efficacy of BTE in maintaining skeletal health is close to that of 17?-estradiol. This study suggests that simultaneous use of BTE is promising as a prospective candidate for adjunctive therapies for calcium supplementation in the early stage of menopausal bone changes. PMID:23984184

Das, Asankur Sekhar; Banerjee, Maitrayee; Das, Dolan; Mukherjee, Sandip; Mitra, Chandan

2013-01-01

358

Potential preventive role of lactic acid bacteria against aflatoxin M? immunotoxicity and genotoxicity in mice.  

PubMed

Aflatoxin M1 (AFM1) is a mycotoxin produced by numerous Aspergillus species in pre- or post-harvest cereals and milk. Exposure to AFM1 imparts potent economic losses in the livestock industry. Toxicologically, it also causes severe immune system problems. The aims of this study were to evaluate a new AFM1-binding/degrading microorganism for biologic detoxification, to examine its ability to degrade AFM1 in liquid medium, and to evaluate its potential for in vivo preventative effects against AFM1-induced immunotoxicity and genotoxicity in mice. Lactobacillus plantarum MON03 (LP) isolated from Tunisian artisanal butter was found to display significant binding ability to AFM1 in PBS (93%) within 24?h of incubation. Further, the LP was able to tolerate gastric acidity, bile salts, and adhere efficiently to Caco-3 cells in vitro. The in vivo study used Balb/c mice that received either vehicle (control), LP only (at 1?×?10(9)CFU/L, ?1?mg/kg bw), AFM1 (100?mg/kg bw), or AFM1?+?LP daily for 15 days (by gavage); two other groups received a single dose of colchicine (4?mg/kg) or mitomycin C (1?mg/kg) as positive controls for induction of micronuclei and chromosomal aberrations, respectively. The results showed that, compared to in control mice, AFM1 treatment led to significantly decreased body weight gains, and caused cytotoxic/genotoxic effects as indicated by increases in frequencies of polychromatic erythrocytes, as well as those with micronucleation (PCEMN) and chromosomal aberrations, among bone marrow cells. The concurrent administration of LP with AFM1 strongly reduced the adverse effects of AFM1 on each parameter. Mice receiving AFM1?+?LP co-treatment displayed no significant differences in the assayed parameters as compared to the control mice. By itself, the bacteria caused no adverse effects. Based on the data, it is concluded that the test bacteria could potentially be beneficial in the detoxification of AFM1-contaminated foods and feeds for humans and animals. PMID:24738739

Ben Salah-Abbès, Jalila; Abbès, Samir; Jebali, Rania; Haous, Zohra; Oueslati, Ridha

2015-01-01

359

Combinatorial chemopreventive effect of butyric acid, nicotinamide and calcium glucarate against the 7,12-dimethylbenz(a)anthracene induced mouse skin tumorigenesis attained by enhancing the induction of intrinsic apoptotic events.  

PubMed

We explored the basis of the combinatorial chemopreventive effect of butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) on mouse skin exposed to 7,12-dimethylbenz(a)anthracene (DMBA). We studied the effects of topical application of DMBA in the presence or absence of BA, NA and CAG on the regulators of apoptosis. DMBA treatment suppressed Bax, Bax/Bcl-2 ratio, release of cyt c, Apaf1, caspase-9, -3 mediated apoptosis. Downregulation of p21 and upregulation of Bcl-2, mut p53 were also observed in only DMBA treated mice. Simultaneous application of BA, NA and CAG induced a mitochondria-mediated apoptosis, characterized by a rise in the Bax, Bax/Bcl-2 ratio, release of cyt c, upregulation of Apaf1 with down-stream activation of caspase-9, -3. Furthermore treatment with BA, NA and CAG demonstrated an upregulation of p21 and downregulation of Bcl-2, mut p53. But this effect was enhanced in the presence of all the three compounds together in combination. Chemoprevention by a combination of BA, NA and CAG by inducing the apoptosis, the natural cell death, suggest the importance of the potential combinational strategies capable of preventing skin tumor development. PMID:25478867

Tiwari, Prakash; Sahay, Satya; Pandey, Manuraj; Qadri, Syed S Y H; Gupta, Krishna P

2015-01-25

360

Simultaneous estimation of ramipril, acetylsalicylic acid and atorvastatin calcium by chemometrics assisted UV-spectrophotometric method in capsules.  

PubMed

In the present work, three different spectrophotometric methods for simultaneous estimation of ramipril, aspirin and atorvastatin calcium in raw materials and in formulations are described. Overlapped data was quantitatively resolved by using chemometric methods, viz. inverse least squares (ILS), principal component regression (PCR) and partial least squares (PLS). Calibrations were constructed using the absorption data matrix corresponding to the concentration data matrix. The linearity range was found to be 1-5, 10-50 and 2-10 ?g mL-1 for ramipril, aspirin and atorvastatin calcium, respectively. The absorbance matrix was obtained by measuring the zero-order absorbance in the wavelength range between 210 and 320 nm. A training set design of the concentration data corresponding to the ramipril, aspirin and atorvastatin calcium mixtures was organized statistically to maximize the information content from the spectra and to minimize the error of multivariate calibrations. By applying the respective algorithms for PLS 1, PCR and ILS to the measured spectra of the calibration set, a suitable model was obtained. This model was selected on the basis of RMSECV and RMSEP values. The same was applied to the prediction set and capsule formulation. Mean recoveries of the commercial formulation set together with the figures of merit (calibration sensitivity, selectivity, limit of detection, limit of quantification and analytical sensitivity) were estimated. Validity of the proposed approaches was successfully assessed for analyses of drugs in the various prepared physical mixtures and formulations. PMID:21945907

Sankar, A S Kamatchi; Vetrichelvan, Thangarasu; Venkappaya, Devashya

2011-09-01

361

The Nitric Oxide Donor SNAP-Induced Amino Acid Neurotransmitter Release in Cortical Neurons. Effects of Blockers of Voltage-Dependent Sodium and Calcium Channels  

PubMed Central

Background The discovery that nitric oxide (NO) functions as a signalling molecule in the nervous system has radically changed the concept of neuronal communication. NO induces the release of amino acid neurotransmitters but the underlying mechanisms remain to be elucidated. Findings The aim of this work was to study the effect of NO on amino acid neurotransmitter release (Asp, Glu, Gly and GABA) in cortical neurons as well as the mechanism underlying the release of these neurotransmitters. Cortical neurons were stimulated with SNAP, a NO donor, and the release of different amino acid neurotransmitters was measured by HPLC. The involvement of voltage dependent Na+ and Ca2+ channels as well as cGMP in its mechanism of action was evaluated. Conclusions Our results indicate that NO induces release of aspartate, glutamate, glycine and GABA in cortical neurons and that this release is inhibited by ODQ, an inhibitor of soluble guanylate cyclase. Thus, the NO effect on amino acid neurotransmission could be mediated by cGMP formation in cortical neurons. Our data also demonstrate that the Na+ and Ca2+ voltage- dependent calcium channels are involved in the NO effects on cortical neurons. PMID:24598811

Merino, José Joaquín; Arce, Carmen; Naddaf, Ahmad; Bellver-Landete, Victor; Oset-Gasque, Maria Jesús; González, María Pilar

2014-01-01

362

Population Pharmacokinetics and Exposure-Uric Acid Analyses After Single and Multiple Doses of ABT-639, a Calcium Channel Blocker, in Healthy Volunteers.  

PubMed

ABT-639 is a selective T-type calcium channel blocker with efficacy in a wide range of preclinical models of nociceptive and neuropathic pain. In the current first-in-human (FIH) study, the pharmacokinetics, tolerability, and safety of ABT-639 after single- (up to 170 mg) and multiple doses (up to 160 mg BID) were evaluated in healthy volunteers in a randomized, double-blinded, placebo-controlled manner. ABT-639 demonstrated acceptable safety and pharmacokinetic profiles in human. Results from assessment of the routine laboratory variables showed an unexpected statistically significant and clinically relevant decrease in blood uric acid with the increase in ABT-639 dose, which is possibly due to inhibition in URAT1 transporter. Pharmacokinetic/pharmacodynamic models were constructed to characterize the relationship between ABT-639 exposure and uric acid response. The final model was a mechanism-based indirect response pharmacodynamic model with the stimulation of uric acid elimination by ABT-639. The model estimated K in values in males and females were 10.2 and 7.13 ?mol/h, respectively. The model estimated K out was 0.033 1/h. ABT-639 concentration that can produce 50% stimulation in uric acid elimination was estimated to be 8,070 ng/mL. Based on the final model, further simulations were conducted to predict the effect of ABT-639 on uric acid in gout patients. The simulation results indicated that, if the urate-lowering response to ABT-639 in gout patients is similar to that in healthy subjects, ABT-639 BID doses of 140 mg or higher would be expected to provide clinically meaningful lowering of blood uric acid levels below the 380 ?mol/L solubility limit of monosodium urate. PMID:25567367

An, Guohua; Liu, Wei; Duan, W Rachel; Nothaft, Wolfram; Awni, Walid; Dutta, Sandeep

2015-03-01

363

Aspirin prevents wound-induced gene expression in tomato leaves by blocking jasmonic acid biosynthesis  

Microsoft Academic Search

Jasmonic acid (JA) and its methyl ester, like mechanical wounding, strongly induce accumulation of proteinase inhibitor II (Pin2) in tomato and potato leaves. In plants, JA is synthesized from a-linolenic acid by a lipoxygenase (LOX)-mediated oxygenation leading to 13-hydroxyperoxylinolenic acid (13-HPLA) which is then subsequently transformed to JA by the action of hydroperoxide-dehydrase activity and additional modification steps. Both the

Hugo Pena-Cortés; Tanja Albrecht; Salomé Prat; Elmar W. Weiler; Lothar Willmitzer

1993-01-01

364

Retinoic acid prevents Chlamydia pneumoniae-induced foam cell development in a mouse model of atherosclerosis.  

PubMed

Chlamydia pneumoniae, a common respiratory pathogen, has been associated with cardiovascular disease. C. pneumoniae infection accelerates atherosclerotic lesion development in hyperlipidemic animals. Retinoic acid, an anti-oxidant, inhibits infection of endothelial cells by C. pneumoniae. The present study demonstrated that retinoic acid suppresses the acceleration of foam cell lesion development induced by C. pneumoniae in hyperlipidemic C57BL/6J mice. Retinoic acid treatment had no effect on foam cell lesion development in uninfected animals. Lung infection and duration was decreased in treated mice, suggesting one mechanism by which retinoic acid reduces C. pneumoniae-accelerated foam cell lesion formation in hyperlipidemic mice. PMID:18678272

Jiang, Shinn-Jong; Campbell, Lee Ann; Berry, Mark W; Rosenfeld, Michael E; Kuo, Cho-Chou

2008-10-01

365

Periparturient effects of feeding a low dietary cation-anion difference diet on acid-base, calcium, and phosphorus homeostasis and on intravenous glucose tolerance test in high-producing dairy cows.  

PubMed

Feeding rations with low dietary cation-anion difference (DCAD) to dairy cows during late gestation is a common strategy to prevent periparturient hypocalcemia. Although the efficacy of low-DCAD rations in reducing the incidence of clinical hypocalcemia is well documented, potentially deleterious effects have not been explored in detail. The objective of the study presented here was to determine the effect of fully compensated metabolic acidosis on calcium and phosphorus homeostasis, insulin responsiveness, and insulin sensitivity as well as on protein metabolism. Twenty multiparous Holstein-Friesian dairy cows were assigned to 1 of 2 treatment groups and fed a low-DCAD ration (DCAD = -9 mEq/100g, group L) or a control ration (DCAD = +11 mEq/100g, group C) for the last 3 wk before the expected calving date. Blood and urine samples were obtained periodically between 14 d before to 14 d after calving. Intravenous glucose tolerance tests and 24-h volumetric urine collection were conducted before calving as well as 7 and 14 d postpartum. Cows fed the low-DCAD ration had lower urine pH and higher net acid excretion, but unchanged blood pH and bicarbonate concentration before calving. Protein-corrected plasma Ca concentration 1 d postpartum was higher in cows on the low-DCAD diet when compared with control animals. Urinary Ca and P excretion was positively associated with urine net acid excretion and negatively associated with urine pH. Whereas metabolic acidosis resulted in a 6-fold increase in urinary Ca excretion, the effect on renal P excretion was negligible. A more pronounced decline of plasma protein and globulin concentration in the periparturient period was observed in cows on the low-DCAD diets resulting in significantly lower total protein and globulin concentrations after calving in cows on low-DCAD diets. Intravenous glucose tolerance tests conducted before and after calving did not reveal group differences in insulin response or insulin sensitivity. Our results indicate that fully compensated metabolic acidosis increased the Ca flux resulting in increased urinary calcium excretion before calving and increased plasma Ca concentration on the day after calving, whereas the effect on P homeostasis was unlikely to be clinically relevant. The clinical relevance of the effect of metabolic acidosis on the plasma protein and globulin concentration is unclear but warrants further investigation. PMID:21257041

Grünberg, W; Donkin, S S; Constable, P D

2011-02-01

366

Exogenous polyamines elicit herbivore-induced volatiles in lima bean leaves: involvement of calcium, H2O2 and Jasmonic acid.  

PubMed

We investigated the role of polyamines (PAs) in lima bean (Phaseolus lunatus) leaves on the production of herbivorous mite (Tetranychus urticae)-induced plant volatiles that attract carnivorous natural enemies of the herbivores. To do this, we focused on the effects of the exogenous PAs [cadaverine, putrescine, spermidine and spermine (Spm)] on the production of volatiles, H(2)O(2) and jasmonic acid (JA) and the levels of defensive genes, cytosolic calcium and reactive oxygen species (ROS). Among the tested PAs, Spm was the most active in inducing the production of volatile terpenoids known to be induced by T. urticae. An increase in JA levels was also found after Spm treatment, indicating that Spm induces the biosynthesis of JA, which has been shown elsewhere to regulate the production of some volatile terpenoids. Further, treatment with JA and Spm together resulted in greater volatile emission than that with JA alone. In a Y-tube olfactometer, leaves treated with Spm + JA attracted more predatory mites (Phytoseiulus persimilis) than those treated with JA alone. After treatment with Spm + JA, no effects were found on the enzyme activity of polyamine oxidase and copper amine oxidase. However, induction of calcium influx and ROS production, and increased enzyme activities and gene expression for NADPH oxidase complex, superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase and glutathione peroxidase were found after treatment with Spm + JA. These results indicate that Spm plays an important role in the production of T. urticae-induced lima bean leaf volatiles. PMID:19884250

Ozawa, Rika; Bertea, Cinzia M; Foti, Maria; Narayana, Ravishankar; Arimura, Gen-Ichiro; Muroi, Atsushi; Horiuchi, Jun-Ichiro; Nishioka, Takaaki; Maffei, Massimo E; Takabayashi, Junji

2009-12-01

367

Cooperative effects of polarization and polyaspartic acid on formation of calcium carbonate films with a multiple phase structure on oriented calcite substrates  

NASA Astrophysics Data System (ADS)

We demonstrated the crystallization of calcium carbonate (CaCO3) on polarized calcite single crystal substrates with three different orientations characterized by the (10.0), (00.1), and (10.4) planes in the presence of polyaspartic acid (PAsp) as an organic additive. The precipitates had a multiple phase structure with thin-film-like and hemispherical forms and were a mixture of calcite, aragonite, and vaterite. The main component of the thin-film-like layers was calcite elongated along the c-axis, regardless of the differently oriented calcite substrates, while the main component of the hemispherical layers was aragonite. The individual crystals of each CaCO3 polymorph shaped the morphology of the mesocrystals. Calcite-aragonite complex films with two distinct structures are similar to those found in pearls and bivalve shells. The combined effect of a surface electric field by virtue of the polarized calcite substrates and PAsp promoted the formation of the thin-film-like layers and moreover, acted remarkably on the negatively charged surface of each oriented calcite substrate. The matching between the ?-sheets of PAsp and the calcium-ion arrangement on top of the oriented calcite substrates explained the preferential calcite crystallization in the form of the thin-film-like layers and why calcite precipitates are in the following sequence: (00.1)>(10.4)>(10.0).

Wada, Norio; Horiuchi, Naohiro; Nakamura, Miho; Nozaki, Kosuke; Hiyama, Tetsuo; Nagai, Akiko; Yamashita, Kimihiro

2014-09-01

368

Fluorescence and FT-IR spectroscopic studies of Suwannee river fulvic acid complexation with aluminum, terbium and calcium  

Microsoft Academic Search

In this study fluorescence emission and IR spectroscopy have been used to investigate the interaction of the class A (oxygen seeking ‘hard acid’) metal Al3+, with Suwannee River fulvic acid. Addition of Al3+ ion results in a significant enhancement in fulvic acid fluorescence emission (at ?em=424 nm) and significant red shift of the excitation wavelength (from ?ex=324 nm to ?ex=344

Kelly M. Elkins; Donald J. Nelson

2001-01-01

369

A full-scale porous reactive wall for prevention of acid mine drainage  

Microsoft Academic Search

The generation and release of acidic drainage containing high concentrations of dissolved metals from decommissioned mine wastes is an environmental problem of international scale. A potential solution to many acid drainage problems is the installation of permeable reactive walls into aquifers affected by drainage water derived from mine waste materials. A permeable reactive wall installed into an aquifer impacted by

Shawn G. Benner; David W. Blowes; Carol J. Ptacek

1997-01-01

370

Treatment and prevention systems for acid mine drainage and halogenated contaminants  

DOEpatents

Embodiments include treatments for acid mine drainage generation sources (10 perhaps by injection of at least one substrate (11) and biologically constructing a protective biofilm (13) on acid mine drainage generation source materials (14). Further embodiments include treatments for degradation of contaminated water environments (17) with substrates such as returned milk and the like.

Jin, Song (Fort Collins, CO); Fallgren, Paul H. (Laramie, WY); Morris, Jeffrey M. (Laramie, WY)

2012-01-31

371

Preventive effects of amino acids on the toxicity of copper to Daphnia magna  

Microsoft Academic Search

The protective role of 18 amino acids on the acute toxicity of Cu in a fresh water cladoceran, Daphnia magna is reported. One hundred percent mortality in 48 hr of exposure occured at 0.56 mg L-1 of Cu or higher. A dose of each tested amino acid (10 mg L-1 was found to significantly neutralize the toxic effect of Cu

B. S. Khangarot; P. K. Ray; Harish Chandra

1987-01-01

372

Melatonin Prevents Myeloperoxidase Heme Destruction and the Generation of Free Iron Mediated by Self-Generated Hypochlorous Acid  

PubMed Central

Myeloperoxidase (MPO) generated hypochlorous acid (HOCl) formed during catalysis is able to destroy the MPO heme moiety through a feedback mechanism, resulting in the accumulation of free iron. Here we show that the presence of melatonin (MLT) can prevent HOCl-mediated MPO heme destruction using a combination of UV-visible photometry, hydrogen peroxide (H2O2)-specific electrode, and ferrozine assay techniques. High performance liquid chromatography (HPLC) analysis showed that MPO heme protection was at the expense of MLT oxidation. The full protection of the MPO heme requires the presence of a 1:2 MLT to H2O2 ratio. Melatonin prevents HOCl–mediated MPO heme destruction through multiple pathways. These include competition with chloride, the natural co-substrate; switching the MPO activity from a two electron oxidation to a one electron pathway causing the buildup of the inactive Compound II, and its subsequent decay to MPO-Fe(III) instead of generating HOCl; binding to MPO above the heme iron, thereby preventing the access of H2O2 to the catalytic site of the enzyme; and direct scavenging of HOCl. Collectively, in addition to acting as an antioxidant and MPO inhibitor, MLT can exert its protective effect by preventing the release of free iron mediated by self-generated HOCl. Our work may establish a direct mechanistic link by which MLT exerts its antioxidant protective effect in chronic inflammatory diseases with MPO elevation. PMID:25835505

Shaeib, Faten; Khan, Sana N.; Ali, Iyad; Najafi, Tohid; Maitra, Dhiman; Abdulhamid, Ibrahim; Saed, Ghassan M.; Pennathur, Subramaniam; Abu-Soud, Husam M.

2015-01-01

373

Prevention of peritendinous adhesions with electrospun ibuprofen-loaded poly(L-lactic acid)-polyethylene glycol fibrous membranes.  

PubMed

Physical barriers are commonly used to reduce peritendinous adhesion after injury. However, the inflammatory response to surgery cannot be prevented. This study was designed to evaluate the ability of ibuprofen-loaded poly(l-lactic acid)-polyethylene glycol (PELA) diblock copolymer fibrous membranes in preventing adhesion formation and reduce inflammation. Electrospun PELA fibrous membranes underwent mechanical testing and were characterized by morphology, surface wettability, drug release, and degradation. Results of an in vitro drug release study showed that a burst release was followed by sustained release from fibrous membranes with high initial ibuprofen content. Fewer L929 mouse fibroblasts adhered to and proliferated on the ibuprofen-loaded PELA fibrous membrane compared with tissue culture plates or PELA fibrous membrane without ibuprofen. In a chicken model of flexor digitorum profundus tendon surgery, the ibuprofen-loaded PELA fibrous membranes prevented tissue adhesion and significantly reduced inflammation. Taken together, these results demonstrate that ibuprofen-loaded PELA fibrous membranes prevent peritendinous adhesion formation better than membranes that do not contain ibuprofen, through anti-adhesion and anti-inflammatory actions. PMID:23013368

Liu, Shen; Hu, Changmin; Li, Fengfeng; Li, Xu-jun; Cui, Wenguo; Fan, Cunyi

2013-02-01

374

[Prevention and therapeutic effects of sika deer velvet collagen hydrolysate on osteoporosis in rats by retinoic acid].  

PubMed

The objective was to evaluate the preventive and therapeutic effects of the collagen hydrolysate extracted from Sika deer velvet (CSDV) on osteoporosis rats induced by retinoicacid. Histomorphometric indices and serum biochemical parameters were measured in osteoporosis rats treated with/without antler collagen and in sham-operated rats. Our results were as follows: compared with the osteoporosis group, significant elevation in the levels of bone mineral density (BMD), Ca, P and static histomorphometric indexes and biomechanical properties, but reduction in the level of serum alkaline phosphatase (ALP) were observed in antler collagen-treated groups. However, the above function with the collagenase solution velvet material varied with the different doses. In conclusion, the extracted collagen is found to play a role in the prevention and treatment of osteoporosis rats by retinoic acid. PMID:20545204

Li, Yinqing; Zhao, Yu; Sun, Xiaodi; Qu, Xiaobo

2010-03-01

375

Tauroursodeoxycholic acid prevents stress induced aggregation of proteins in vitro and promotes PERK activation in HepG2 cells.  

PubMed

Tauroursodeoxycholic acid (TUDCA) a bile salt and chemical chaperone reduces stress-induced aggregation of proteins; activates PERK [PKR (RNA-dependent protein kinase)-like ER (endoplasmic reticulum) kinase] or EIF2AK3, one of the hall marks of ER stress induced unfolded protein response (UPR) in human hepatoblastoma HepG2 cells; prevents heat and dithiothreitol (DTT) induced aggregation of BSA (bovine serum albumin), and reduces ANS (1-anilino-naphthalene-8-sulfonate) bound BSA fluorescence in vitro. TUDCA inactivates heat treated, but not the native EcoR1 enzyme, and reduces heat-induced aggregation and activity of COX-1 (cyclooxygenase enzyme-1) in vitro. These findings suggest that TUDCA binds to the hydrophobic regions of proteins and prevents their subsequent aggregation. This may stabilize unfolded proteins that can mount UPR or facilitate their degradation through cellular degradation pathways. PMID:25579883

Gani, Amina R; Uppala, Jagadeesh Kumar; Ramaiah, Kolluru V A

2015-02-15

376

Aurin tricarboxylic acid, the anti-AIDS compound, prevents the binding of interferon-alpha to its receptor.  

PubMed

Binding of HIV to its receptor, the CD4 molecule of lymphocytes, can be prevented by chemical agents. These agents could be considered as potential anti-AIDS drugs. We have shown that aurin tricarboxylic acid (ATA, 3 microM) specifically blocks the binding of gp120, the HIV coat protein, to the CD4 molecule. We have also found that ATA prevents the binding of interferon-alpha to its receptor in a dose-dependent manner (12-50 microM range). Membrane potential shift, associated with binding of interferon-alpha to its receptor, was also blocked by ATA in a dose-dependent fashion. Our results indicate that potential anti-AIDS drugs should be screened for such undesired side effects. PMID:2147104

Gan, Y X; Weaver, J L; Pine, P S; Zoon, K C; Aszalos, A

1990-11-15

377

Acid precipitation and food quality: inhibition of growth and survival in black ducks and mallards by dietary aluminum, calcium, and phosphorus.  

PubMed

In areas impacted by acid precipitation, water chemistry of acidic ponds and streams often changes, resulting in increased mobilization of aluminum and decreased concentration of calcium carbonate. Aluminum binds with phosphorus and inhibits its uptake by organisms. Thus, invertebrate food organisms used by waterfowl may have inadequate Ca and P or elevated Al for normal growth and development. Acid rain and its effects may be one of the factors negatively impacting American black ducks (Anas rubripes) in eastern North America. One-day old mallards (A. platyrhynchos) and black ducks were placed on one of three Ca:P regimens: low:low (LL), normal:normal (NN), and low:high (LH) with each regimen divided further into three or four Al levels for 10 weeks. Forty-five % of the black ducks died on nine different diets whereas only 28% of the mallards died on three different diets. Mortality was significantly related to diet in both species. Growth rates for body weight, culmens, wings, and tarsi of both species on control diets exceeded those on many treatment diets but the differences were less apparent for mallards than for black ducks. Differences among treatments were due to both Ca:P and Al levels. PMID:2353844

Sparling, D W

1990-01-01

378

Acid precipitation and food quality: Inhibition of growth and survival in black ducks and mallards by dietary aluminum, calcium and phosphorus  

USGS Publications Warehouse

In areas impacted by acid precipitation, water chemistry of acidic ponds and streams often changes, resulting in increased mobilization of aluminum and decreased concentration of calcium carbonate. Aluminum binds with phosphorus and inhibits its uptake by organisms. Thus, invertebrate food organisms used by waterfowl may have inadequate Ca and P or elevated Al for normal growth and development. Acid rain and its effects may be one of the factors negatively impacting American black ducks (Anas rubripes) in eastern North America. One-day old mallards (A. platyrhynchos) and black ducks were placed on one of three Ca:P regimens: low:low (LL), normal:normal (NN), and low:high (LH) with each regimen divided further into three or four Al levels for 10 weeks. Forty-five % of the black ducks died on nine different diets whereas only 28% of the mallards died on three different diets. Mortality was significantly related to diet in both species. Growth rates for body weight, culmens, wings, and tarsi of both species on control diets exceeded those on many treatment diets but the differences were less apparent for mallards than for black ducks. Differences among treatments were due to both Ca:P and Al levels.

Robbins, C.S.

1990-01-01

379

Influence of diet transition on serum calcium and phosphorus and fatty acids in zoo giraffe (Giraffa camelopardalis).  

PubMed

In response to new recommendations for feeding giraffe in zoos, giraffe (n = 6) were transitioned from a typical hoofstock diet to diets containing reduced starch, protein, Ca and P and added n3 fatty acids. This diet was fed as a 50:50 mix with alfalfa and grass hay. Over the next 4 years, serum Ca, P, and fatty acids were measured every 6 months (summer and winter). Serum Ca was not affected by season (P = 0.67) or by diet (P = 0.12). Serum P was not affected season (P = 0.14), but was reduced by diet (P<0.01), and serum Ca:P was also increased by diet (P<0.01). The ratio of serum Ca:P tended to be affected by season (P = 0.07), in which animals tended to have greater Ca:P during the summer vs. the winter. The diet transition resulted in reduced serum saturated fatty acids (including lauric, myristic, palmitic, arachidic, and behenic acids), and increases in n6 fatty acids (including linolenic and arachidonic acids) and n3 fatty acids (docosahexaenoic acid) (P<0.05 for each). Overall, this diet transition resulted in blood nutrient profiles that more closely match that of values found in free-ranging giraffe. PMID:20954252

Koutsos, E A; Armstrong, D; Ball, R; Dikeman, C; Hetherington, J; Simmons, L; Valdes, E V; Griffin, M

2011-01-01

380

Multiple Calcium Stores: Separate but Interacting  

NSDL National Science Digital Library

Multiple mechanisms exist for increasing the concentration of intracellular calcium. This Perspective by Lee is one in a series on intracellular calcium release mechanisms and focuses on the calcium store operated by nicotinic acid adenine dinucleotide phosphate (NAADP). The characterization of the NAADP-operated calcium store as separate from the inositol trisphosphate (IP3)-operated and cyclic ADP-ribose (cADPR)-operated calcium stores is discussed. Lee also addresses the role of NAADP in regulating intracellular calcium fluctuations during fertilization and hormonal activation of pancreatic acinar cells.

Hon Cheung Lee (University of Minnesota; Department of Pharmacology REV)

2000-07-11

381

The role of extracellular free-calcium gradients in gravitropic signalling in maize roots  

NASA Technical Reports Server (NTRS)

Gravitropism in roots has been proposed to depend on a downward redistribution of calcium across the root cap. However, because of the many calcium-binding sites in the apoplast, redistribution might not result in a physiologically effective change in the apoplasmic calcium activity. To test whether there is such a change, we measured the effect of gravistimulation on the calcium activity of statocyte cell walls with calcium-specific microelectrodes. Such a measurement must be made on a tissue with gravity sensing cells at the surface. To obtain such a tissue, decapped maize roots (Zea mays L. cv. Golden Cross Bantam) were grown for 31 h to regenerate gravitropic sensitivity, but not root caps. The calcium activity in the apoplasm surrounding the gravity-sensing cells could then be measured. The initial pCa was 2.60 +/- 0.28 (approx 2.5 mM). The calcium activity on the upper side of the root tip remained constant for 10 min after gravistimulation, then decreased 1.7-fold. On the lower side, after a similar lag the calcium activity increased 1.6-fold. Control roots, which were decapped but measured before recovering gravisensitivity (19 h), showed no change in calcium activity. To test whether this gradient is necessary for gravitropic curvature, we eliminated the calcium activity gradient during gravitropism by applying a mobile calcium-binding site (dinitro-BAPTA; 1,2-bis(2-amino-5-nitro-phenoxy)ethane-N,N,N',N'-tetraacetic acid) to the root cap; this treatment eliminated gravicurvature. A calcium gradient may be formed by proton-induced calcium desorption if there is a proton gradient. Preventing the formation of apoplastic pH gradients, using 10 and 50 mM 2-(N-morpholino)ethanesulfonic acid (Mes) buffer or 10 mM fusicoccin to stimulate proton excretion maximally, did not inhibit curvature; therefore the calcium gradient is not a secondary effect of a proton gradient. We have found a distinct and rapid differential in the apoplasmic calcium activity between the upper and lower sides of gravistimulated maize root tips which is necessary for gravitropism.

Bjorkman, T.; Cleland, R. E.

1991-01-01

382

Calcium channel blocker-induced gingival hyperplasia: case report and review of this iatrogenic disease.  

PubMed

Gingival hyperplasia is a common disorder associated with phenytoin and cyclosporine therapy. However, induction of this condition by calcium channel blockers is less well known. Inflammation of the gingival tissue from bacterial plaque and the subsequent development of gingival crevicular fluid may allow sequestration of the calcium channel blocker, thus predisposing the tissue to a localized toxic effect and the development of gingival hyperplasia. Calcium channel blockers have cellular effects similar to those of phenytoin and cyclosporine, including the production of a localized folic acid deficiency. All of the available calcium channel blockers have been reported to cause gingival hyperplasia. Treatment options include meticulous plaque control, and in severe cases, gingivectomy. Gingival hyperplasia can be prevented with meticulous plaque control or avoidance of the offending medication. PMID:7964547

Lawrence, D B; Weart, C W; Laro, J J; Neville, B W

1994-11-01

383

Once-yearly zoledronic acid in the prevention of osteoporotic bone fractures in postmenopausal women  

PubMed Central

Zoledronic acid is a nitrogen-containing, third-generation bisphosphonate that has recently been approved for the treatment of postmenopausal osteoporosis as an annual intravenous infusion. Zoledronic acid is an antiresorptive agent which has a high affinity for mineralized bone and especially for sites of high bone turnover. Zoledronic acid is excreted by the kidney without further metabolism. Zoledronic acid administered as a 5 mg intravenous infusion annually increases bone mineral density in the lumbar spine and femoral neck by 6.7% and 5.1% respectively and reduces the incidence of new vertebral and hip fractures by 70% and 41% respectively in postmenopausal women with osteoporosis. Most common side effects are post-dose fever, flu-like symptoms, myalgia, arthralgia, and headache which usually occur in the first 3 days after infusion and are self-limited. Rare adverse effects include renal dysfunction, hypocalcemia, atrial fibrillation, and osteonecrosis of the jaw. PMID:18982915

Lambrinoudaki, Irene; Vlachou, Sophia; Galapi, Fotini; Papadimitriou, Dimitra; Papadias, K

2008-01-01

384

Ketogenic Essential Amino Acids Modulate Lipid Synthetic Pathways and Prevent Hepatic Steatosis in Mice  

Microsoft Academic Search

BackgroundAlthough dietary ketogenic essential amino acid (KAA) content modifies accumulation of hepatic lipids, the molecular interactions between KAAs and lipid metabolism are yet to be fully elucidated.Methodology\\/Principal FindingsWe designed a diet with a high ratio (E\\/N) of essential amino acids (EAAs) to non-EAAs by partially replacing dietary protein with 5 major free KAAs (Leu, Ile, Val, Lys and Thr) without

Yasushi Noguchi; Natsumi Nishikata; Nahoko Shikata; Yoshiko Kimura; Jose O. Aleman; Jamey D. Young; Naoto Koyama; Joanne K. Kelleher; Michio Takahashi; Gregory Stephanopoulos; Thorkild I. A. Sorensen

2010-01-01

385

Prevention of photocarcinogenesis and UV?induced immunosuppression in mice by topical tannic acid  

Microsoft Academic Search

Topical application of tannic acid, a phenolic antioxidant derived from plants, was found to inhibit the cutaneous carcinogenesis and the immunosuppression induced by ultraviolet B (UVB) irradiation with no visible toxicity. BALB\\/cAnNTacfBR mice were treated with 200 ?g of tannic acid three times weekly for two weeks before UV treatments began and throughout the experiment. UVB irradiation consisted of five

Helen L. Gensler; Kevin E. Gerrish; Tedine Williams; Ganesh Rao; John Kittelson

1994-01-01

386

Antioxidant properties of an endogenous thiol: Alpha-lipoic acid, useful in the prevention of cardiovascular diseases.  

PubMed

In the past few years, a growing interest has been given to the possible antioxidant functions of a natural acid, synthesized in human tissues: alpha-lipoic acid (ALA). Both the oxidized (disulfide) and reduced (dithiol: dihydrolipoic acid, DHLA) forms of ALA show antioxidant properties. ALA administered in the diet accumulates in tissues, and a substantial part is converted to DHLA via a lipoamide dehydrogenase. Commercial ALA is usually a racemic mixture of the R and S forms. Chemical studies have indicated that ALA scavenges hydroxyl radicals, hypochlorous acid, and singlet oxygen. ALA exerts antioxidant effects in biological systems not only through direct ROS quenching but also via transition metal chelation. ALA has been shown to possess a number of beneficial effects both in the prevention and treatment of diabetes in experimental conditions. ALA presents beneficial effects in the management of symptomatic diabetic neuropathy and has been used in this context in Germany for more than 30 years. In cardiovascular disease, dietary supplementation with ALA has been successfully employed in a variety of in vivo models: ischemia-reperfusion, heart failure, and hypertension. More mechanistic and human in vivo studies are needed to determine whether optimizing the dietary intake of ALA can help to decrease cardiovascular diseases. A more complete understanding of cellular biochemical events that influence oxidative damage is required to guide future therapeutic advances. PMID:19998523

Ghibu, Stéliana; Richard, Carole; Vergely, Catherine; Zeller, Marianne; Cottin, Yves; Rochette, Luc

2009-11-01

387

Reactive blue prevented caffeine-induced neurotoxicity by an independent mechanism from intracellular calcium currents in cell culture from auditory cortex of rats.  

PubMed

Neurotoxicity induced by caffeine in auditory-neuron cultures was studied in rat pups. For possible protective effect, reactive blue (RB) alone and in combination with dantrolene were tested in subsequent doses. RB was found to have a U-shape neuroprotective effect in caffeine neurotoxicity. Dantrolene was also tested in combined application in caffeine neurotoxicity. Despite the existing neuroprotection, no additional protection was obtained with various doses of dantrolene. In conclusion, RB may exert neuroprotective effect by increasing intracellular ATP levels in caffeine toxicity. High ATP levels may postpone the toxic cascade. Dantrolene as an endoplasmic reticulum calcium release blocker had no additional protective effect, suggesting that the increased intracellular calcium levels may be involved in later states of the toxic cascade, occurring after the compensatory phase of the cell death. PMID:15764004

Uçüncü, Harun; Bakuridze, Kakhi; Düzenli, Selma; Halici, Zekai; Büyükokuroglu, Mehmet Emin; Gepdiremen, Akçahan

2005-02-01

388

Fatty Acid Profile and Physical Properties of Milk Fat from Cows fed Calcium Salts of Fatty Acids with Varying Unsaturation1  

Microsoft Academic Search

Holstein cows (n = 24) averaging 42 d in milk were used in a randomized complete block design during a 4-wk trial. A control total mixed ration (TMR) was compared with TMR supplemented with Ca salts of fatty acids from canola oil, soybean oil, or linseed oil. The three vegetable oils were progressively more un- saturated; the dominant fatty acids

P. Y. Chouinard; V. Girard; G. J. Brisson

1998-01-01

389

The marine sponge-derived polyketide endoperoxide plakortide F acid mediates its antifungal activity by interfering with calcium homeostasis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plakortide F acid (PFA) is a marine-derived polyketide endoperoxide exhibiting strong inhibitory activity against several clinically important fungal pathogens. In the present study, transcriptional profiling coupled with mutant and biochemical analyses were conducted using the model organism Sacch...

390

Effect of the degree of saturation of hydroxy-fatty acids on the properties of complex calcium-lubricants  

Microsoft Academic Search

1.It has been established that KCa-lubricants can be produced from soaps of HCO and technical 12-H(OH)St of different degrees of hydrogenation (iodine numbers ranging from 6.9 to33 g I2\\/100 g). The lubricants have good operation properties and their mechanical stability exceeds that of KCa-lubricants prepared from stearic acid and synthetic fatty acids.2.Reduction of the iodine number of the saponifiable compounds

Yu. L. Ishchuk; O. Ya. Krentkovskaya; N. K. Man'kovskaya; A. K. Maskaev; V. V. Sinitsyn

1971-01-01

391

INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRIC ANALYSIS OF CALCIUM ISOTOPES IN HUMAN SERUM: A LOW-SAMPLE-VOLUME ACID-EQUILIBRATION METHOD  

Technology Transfer Automated Retrieval System (TEKTRAN)

Analytical methods for measuring the calcium isotope distribution in enriched human serum samples that use low blood volumes, simple preparation methods, and rapid analysis are important in clinical studies of calcium kinetics. Previously, sample preparation by oxalate precipitation typically requi...

392

Synthesis of the cancer preventive peptide lunasin by lactic acid bacteria during sourdough fermentation.  

PubMed

This study aimed to exploit the potential of sourdough lactic acid bacteria to release lunasin during fermentation of cereal and nonconventional flours. The peptidase activities of a large number of sourdough lactic acid bacteria were screened using synthetic substrates. Selected lactic acid bacteria were used as sourdough starters to ferment wholemeal wheat, soybean, barley, amaranth, and rye flours. Proteinase activity during fermentation was characterized by SDS-PAGE analysis of the water-soluble extracts. Albumins having molecular masses of 18 to 22 kDa, which included the size of lunasin precursors, were markedly affected by proteolysis of lactic acid bacteria. After fermentation, lunasin from the water-soluble extracts was quantified, purified, and identified through RP-HPLC and nano-LC-ESI-MS analyses. Compared to control doughs, the concentration of lunasin increased up to 2-4 times during fermentation. Lactobacillus curvatus SAL33 and Lactobacillus brevis AM7 synthesized the highest concentrations of lunasin in all the flours. Besides the presence of the entire lunasin sequence, fragments containing the immunoreactive epitope RGDDDDDDDDD were also found. This study shows that fermentation by lactic acid bacteria increased the concentration of lunasin to levels that would suggest new possibilities for the biological synthesis and for the formulation of functional foods. PMID:22098174

Rizzello, Carlo G; Nionelli, Luana; Coda, Rossana; Gobbetti, Marco

2012-01-01

393

Docosahexaenoic acid prevents paraquat-induced reactive oxygen species production in dopaminergic neurons via enhancement of glutathione homeostasis.  

PubMed

Omega-3 polyunsaturated fatty acid levels are reduced in the substantia nigra area in Parkinson's disease patients and animal models, implicating docosahexaenoic acid (DHA) as a potential treatment for preventing Parkinson's disease and suggesting the need for investigations into how DHA might protect against neurotoxin-induced dopaminergic neuron loss. The herbicide paraquat (PQ) induces dopaminergic neuron loss through the excessive production of reactive oxygen species (ROS). We found that treatment of dopaminergic SN4741 cells with PQ reduced cell viability in a dose-dependent manner, but pretreatment with DHA ameliorated the toxic effect of PQ. To determine the toxic mechanism of PQ, we measured intracellular ROS content in different organelles with specific dyes. As expected, all types of ROS were increased by PQ treatment, but DHA pretreatment selectively decreased cytosolic hydrogen peroxide content. Furthermore, DHA treatment-induced increases in glutathione reductase and glutamate cysteine ligase modifier subunit (GCLm) mRNA expression were positively correlated with glutathione (GSH) content. Consistent with this increase in GCLm mRNA levels, Western blot analysis revealed that DHA pretreatment increased nuclear factor-erythroid 2 related factor 2 (Nrf2) protein levels. These findings indicate that DHA prevents PQ-induced neuronal cell loss by enhancing Nrf2-regulated GSH homeostasis. PMID:25545062

Lee, Hyoung Jun; Han, Jeongsu; Jang, Yunseon; Kim, Soo Jeong; Park, Ji Hoon; Seo, Kang Sik; Jeong, Soyeon; Shin, Soyeon; Lim, Kyu; Heo, Jun Young; Kweon, Gi Ryang

2015-01-30

394

40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...  

Code of Federal Regulations, 2013 CFR

...6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. 721.2076...6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. (a) Chemical...6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt (PMN...

2013-07-01

395

40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...  

Code of Federal Regulations, 2014 CFR

...6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. 721.2076...6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. (a) Chemical...6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt (PMN...

2014-07-01

396

40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...  

Code of Federal Regulations, 2011 CFR

...6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. 721.2076...6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. (a) Chemical...6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt (PMN...

2011-07-01

397

Design of in situ dispersible and calcium cross-linked alginate pellets as intestinal-specific drug carrier by melt pelletization technique.  

PubMed

Conventional alginate pellets underwent rapid drug dissolution and loss of multiparticulate characteristics such as aggregation in acidic medium, thereby promoting oral dose dumping. This study aimed to design sustained-release dispersible alginate pellets through rapid in situ matrix dispersion and cross-linking by calcium salts during dissolution. Pellets made of alginate and calcium salts were prepared using a solvent-free melt pelletization technique that prevented reaction between processing materials during agglomeration and allowed such a reaction to occur only in dissolution phase. Drug release was remarkably retarded in acidic medium when pellets were formulated with water-soluble calcium acetate instead of acid-soluble calcium carbonate. Different from calcium salt-free and calcium carbonate-loaded matrices that aggregated or underwent gradual erosion, rapid in situ solvation of calcium acetate in pellets during dissolution resulted in burst of gas bubbles, fast pellet breakup, and dispersion. The dispersed fragments, though exhibiting a larger specific surface area for drug dissolution than intact matrix, were rapidly cross-linked by Ca(2+) from calcium acetate and had drug release retarded till a change in medium pH from 1.2 to 6.8. Being dispersible and pH-dependent in drug dissolution, these pellets are useful as multiparticulate intestinal-specific drug carrier without exhibiting dose dumping tendency of a "single-unit-like" system via pellet aggregation. PMID:21213311

Nurulaini, Harjoh; Wong, Tin Wui

2011-06-01

398

Disruption of glucose tolerance caused by glucocorticoid excess in rats is partially prevented, but not attenuated, by arjunolic acid.  

PubMed

Arjunolic acid (AA) obtained from plants of the Combretaceae family has shown anti-diabetic effects. Here, we analyzed whether the diabetogenic effects of dexamethasone (DEX) treatment on glucose homeostasis may be prevented or attenuated by the concomitant administration of AA. Adult Wistar rats were assigned to the following groups: vehicle-treated (Ctl), DEX-treated (1 mg/kg body weight intraperitoneally for 5 days) (Dex), AA-treated (30 mg/kg body weight by oral gavage twice per day) (Aa), AA treatment previous to and concomitant to DEX treatment (AaDex), and AA treatment after initiation of DEX treatment (DexAa). AA administration significantly ameliorated (AaDex) (P > 0.05), but did not attenuate (DexAa), the glucose intolerance induced by DEX treatment. AA did not prevent or attenuate the elevation in hepatic glycogen and triacylglycerol content caused by DEX treatment. All DEX-treated rats exhibited hepatic steatosis that seemed to be more pronounced when associated with AA treatment given for a prolonged period (AaDex). Markers of liver function and oxidative stress were not significantly altered among the groups. Therefore, AA administered for a prolonged period partially prevents the glucose intolerance induced by DEX treatment, but it fails to produce this beneficial effect when given after initiation of GC treatment. Since AA may promote further hepatic steatosis when co-administered with GCs, care is required when considering this phytochemical as a hypoglycemiant and/or insulin-sensitizing agent. PMID:25345246

Gonçalves-Neto, Luiz M; Ferreira, Francielle B D; Souza, Luiz; dos Santos, Cristiane; Boschero, Antonio C; Facundo, Valdir A; Santos, Adair R S; Nunes, Everson A; Rafacho, Alex

2014-10-01

399

Rosmarinic acid prevents lipid peroxidation and increase in acetylcholinesterase activity in brain of streptozotocin-induced diabetic rats.  

PubMed

We investigated the efficacy of rosmarinic acid (RA) in preventing lipid peroxidation and increased activity of acetylcholinesterase (AChE) in the brain of streptozotocin-induced diabetic rats. The animals were divided into six groups (n?=?8): control, ethanol, RA 10 mg/kg, diabetic, diabetic/ethanol and diabetic/RA 10 mg/kg. After 21 days of treatment with RA, the cerebral structures (striatum, cortex and hippocampus) were removed for experimental assays. The results demonstrated that the treatment with RA (10 mg/kg) significantly reduced the level of lipid peroxidation in hippocampus (28%), cortex (38%) and striatum (47%) of diabetic rats when compared with the control. In addition, it was found that hyperglycaemia caused significant increased in the activity of AChE in hippocampus (58%), cortex (46%) and striatum (30%) in comparison with the control. On the other hand, the treatment with RA reversed this effect to the level of control after 3 weeks. In conclusion, the present findings showed that treatment with RA prevents the lipid peroxidation and consequently the increase in AChE activity in diabetic rats, demonstrating that this compound can modulate cholinergic neurotransmission and prevent damage oxidative in brain in the diabetic state. Thus, we can suggest that RA could be a promising compound in the complementary therapy in diabetes. PMID:24301255

Mushtaq, Nadia; Schmatz, Roberta; Pereira, Luciane B; Ahmad, Mushtaq; Stefanello, Naiara; Vieira, Juliano M; Abdalla, Fátima; Rodrigues, Marília V; Baldissarelli, Jucimara; Pelinson, Luana Paula; Dalenogare, Diéssica P; Reichert, Karine Paula; Dutra, Eduardo M; Mulinacci, Nádia; Innocenti, Marzia; Bellumori, Maria; Morsch, Vera Maria; Schetinger, Maria Rosa

2014-04-01

400

Interleukin-1? Inhibits Insulin Signaling and Prevents Insulin-Stimulated System A Amino Acid Transport in Primary Human Trophoblasts  

PubMed Central

Interleukin-1? (IL-1?) promotes insulin resistance in tissues such as liver and skeletal muscle; however the influence of IL-1? on placental insulin signaling is unknown. We recently reported increased IL-1? protein expression in placentas of obese mothers, which could contribute to insulin resistance. In this study, we tested the hypothesis that IL-1? inhibits insulin signaling and prevents insulin-stimulated amino acid transport in cultured primary human trophoblast (PHT) cells. Cultured trophoblasts isolated from term placentas were treated with physiological concentrations of IL-1? (10 pg/ml) for 24 hours. IL-1? increased the phosphorylation of insulin receptor substrate-1 (IRS-1) at Ser307 (inhibitory) and decreased total IRS-1 protein abundance but did not affect insulin receptor ? expression. Furthermore, IL-1? inhibited insulin-stimulated phosphorylation of IRS-1 (Tyr612, activation site) and Akt (Thr308) and prevented insulin-stimulated increase in PI3K/p85 and Grb2 protein expression. IL-1? alone stimulated cRaf (Ser338), MEK (Ser221) and Erk1/2 (Thr202/Tyr204) phosphorylation. The inflammatory pathways nuclear factor kappa B and c-Jun N-terminal kinase, which are involved in insulin resistance, were also activated by IL-1? treatment. Moreover, IL-1? inhibited insulin-stimulated System A, but not System L amino acid uptake, indicating functional impairment of insulin signaling. In conclusion, IL-1? inhibited the insulin signaling pathway by inhibiting IRS-1 signaling and prevented insulin-stimulated System A transport, thereby promoting insulin resistance in cultured PHT cells. These findings indicate that conditions which lead to increased systemic maternal or placental IL-1? levels may attenuate the effects of maternal insulin on placental function and consequently fetal growth. PMID:23891856

Aye, Irving L. M. H.; Jansson, Thomas; Powell, Theresa L.

2013-01-01

401

Biodegradable and injectable in situ cross-linking chitosan-hyaluronic acid based hydrogels for postoperative adhesion prevention.  

PubMed

Postsurgical peritoneal adhesions are very common and serious complication after surgery. Biodegradable and injectable hydrogels derived from natural polysaccharides are ideal biomaterials for prevention of postoperative adhesion. In this work, we report a class of injectable, biodegradable, and non-toxic hydrogel derived from N, O-carboxymethyl chitosan (NOCC) and aldehyde hyaluronic acid (A-HA), without requirement of any chemical linkers or radiant light sources. NOCC was prepared by introducing carboxymethyl groups to the N-position and the O-position of chitosan, and A-HA was prepared using periodate oxidation method. The gelation is attributed to the Schiff base between the amino groups of NOCC and aldehyde groups in A-HA, and the hydrogel precursors cross-linked to form a flexible hydrogel. NOCC, A-HA, and NOCC/A-HA hydrogel extract exhibited very low cytotoxicity and hemolysis, and the acute toxicity tests showed that the hydrogel was non-toxic. Besides, the highly porous three-dimensional hydrogel can supported the growth and proliferation of the cells encapsulated in the hydrogels, but was not favorable for the attachment of fibroblasts to the surface, suggesting that the NOCC/A-HA hydrogel can be developed for adhesion prevention. The hydrogel was susceptible to the lysozyme and can be degraded within 2 weeks in vivo. Furthermore, we employed a rat model of sidewall defect-cecum abrasion to investigate the efficacy of NOCC/A-HA hydrogel in preventing post-operative peritoneal adhesions. A significant reduction of peritoneal adhesion formation was found in the NOCC/A-HA-treated group, compared with commercial hyaluronic acid (HA) hydrogel group and normal saline group. In addition, the potential anti-adhesion mechanism of NOCC/A-HA hydrogel was discussed, which may attribute to the combination of barrier function and bioactivity of NOCC and A-HA. PMID:24507411

Li, Ling; Wang, Ning; Jin, Xun; Deng, Rui; Nie, Shihong; Sun, Lu; Wu, Qinjie; Wei, Yuquan; Gong, Changyang

2014-04-01

402

Folic Acid-Based Multivitamin Therapy to Prevent Stroke The Jury Is Still Out  

Microsoft Academic Search

here is a large body of observational and laboratory evidence suggesting but not proving that increasing plasma concentrations of total homocysteine (tHcy) is a causal risk factor for atherothromboembolic ischemic stroke and other vascular events.1-9 Recent publication of the results of the landmark Vitamins in Stroke Prevention (VISP) Trial is the first evidence from a large randomized controlled trial (RCT)

Marc Fisher; Antoni Davalos; Graeme J. Hankey; John W. Eikelboom

403

Corrosion prevention of cold rolled steel using water dispersible lignosulfonic acid doped polyaniline  

NASA Technical Reports Server (NTRS)

The invention provides coatings useful for preventing corrosion of metals. The coatings comprise a film-forming resin and conductive polymers comprising linearly conjugated .pi.-systems and residues of sulfonated lignin or a sulfonated polyflavonoid or derivatives of solfonated lignin or a sulfonated polyflavonoid. The invention also provides a latex formulation of the coatings, and articles of manufacture comprising a metal substrate and a coating in contact with the metal substrate.

Viswanathan, Tito (Inventor)

2007-01-01

404

Corrosion Prevention of Cold Rolled Steel Using Water Dispersible Lignosulfonic Acid Doped Polyaniline  

NASA Technical Reports Server (NTRS)

The invention provides coatings useful for preventing corrosion of metals. The coatings comprise a film-forming resin and conductive polymers comprising linearly conjugated x-systems and residues of sulfonated lignin or a sulfonated polyflavonoid or derivatives of solfonated lignin or a sulfonated polyflavonoid. The invention also provides a latex formulation of the coatings, and articles of manufacture comprising a metal substrate and a coating in contact with the metal substrate.

Viswanathan, Tito (Inventor)

2007-01-01

405

CORROSION PREVENTION OF COLD ROLLED STEEL USING WATER DISPERSIBLE LIGNOSULFONIC ACID DOPED POLYANILINE  

NASA Technical Reports Server (NTRS)

The invention provides coatings useful for preventing corrosion of metals. The coatings comprise a film-forming resin and conductive polymers comprising linearly conjugated pi-systems and residues of sulfonated lignin or a sulfonated polyflavonoid or derivatives of sulfonated lignin or a sulfonated polyflavonoid. The invention also provides a latex formulation of the coatings, and articles of manufacture comprising a metal substrate and a coating in contact with the metal substrate.

Viswanathan, Tito (Inventor)

2005-01-01

406

Effect of various domestic processing and cooking methods on phytic acid and HCl-extractability of calcium, phosphorus and iron of pigeon pea.  

PubMed

Manak, the high yielding cultivator of pigeon pea (Cajanus cajan) released by (International Crop Research Institute for Semi-Arid Tropics) ICRISAT, India was subjected to various domestic processing and cooking methods viz., soaking (6, 12 and 18 h, 30 degrees C), soaking and dehulling, ordinary cooking, pressure cooking and germination (24, 36 and 48 h, 30 degrees C). The unprocessed seeds of this variety contained considerable amounts of phytic acid i.e. 917 mg per 100 g. This antinutrient was reduced significantly (P < 0.05) to varying extents (4-37%) in the processed samples. Except soaking and dehulling, the remaining processing and cooking methods did not lower the contents of total calcium, phosphorus and iron. That HCl-extractability of these dietary essential minerals, an index of their bioavailability, enhanced significantly when the pigeon pea seeds were processed and cooked, may be due to reduction in phytate content, which is known to chelate the minerals. A significant and negative correlation between the phytic acid and HCl-extractability of minerals further strengthens our findings. PMID:10561865

Duhan, A; Khetarpaul, N; Bishnoi, S

1999-01-01

407

Bovine milk-associated calcium as an uncoupling factor of mitochondrial respiration.  

PubMed

Attempts to obtain coupled mitochondria from lactating bovine mammary tissue proved unsuccessful. To ascertain the nature of the uncoupling factor(s) responsible, we chose mitochondria of rat liver as a test system for their established isolation with retention of coupled respiration. Isolated, coupled rat liver mitochondria were uncoupled immediately by addition of microliter amounts of bovine milk and aqueous milk fractions. Dialysis of whey resulted in loss of the uncoupling factor, whereas boiling did not prevent the uncoupling effect. Inclusion in whey of the calcium chelator ethylene glycol-bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid protected rat liver mitochondria from the uncoupling effect. Mitochondrial swelling paralleled whey-induced respiratory uncoupling. When monitored by both oxygen consumption and swelling experiments, loss of respiratory control was correlated with the ionic calcium content of bovine milk. These findings suggest that high ionic calcium in bovine milk caused uncoupling. Extensive washings to remove or chelate calcium or inhibit mitochondrial calcium uptake were ineffective in preventing bovine mammary mitochondrial uncoupling. The implications of these findings suggest large amounts of compartmentalized intracellular calcium in bovine mammary tissue. PMID:7108013

Dreels, J M; Baumrucker, C R

1982-07-01

408

Lipid oxidation in fish oil enriched mayonnaise: calcium disodium ethylenediaminetetraacetate, but not gallic acid, strongly inhibited oxidative deterioration.  

PubMed

The antioxidative effects of gallic acid, EDTA, and extra emulsifier Panodan DATEM TR in mayonnaise enriched with 16% fish oil were investigated. EDTA reduced the formation of free radicals, lipid hydroperoxides, volatiles, and fishy and rancid off-flavors. The antioxidative effect of EDTA was attributed to its ability to chelate free metal ions and iron from egg yolk located at the oil-water interface. Gallic acid reduced the levels of both free radicals and lipid hydroperoxides but promoted slightly the oxidative flavor deterioration in mayonnaise and influenced the profile of volatiles. Gallic acid may therefore promote the decomposition of lipid hydroperoxides to volatile oxidation products. Addition of extra emulsifier reduced the lipid hydroperoxide levels but did not influence the level of free radicals or the oxidative flavor deterioration in mayonnaisse; however, it appeared to alter the profile of volatiles. The effect of the emulsifier on the physical structure and rheological properties depended on the presence of antioxidants. PMID:11262064

Jacobsen, C; Hartvigsen, K; Thomsen, M K; Hansen, L F; Lund, P; Skibsted, L H; Hølmer, G; Adler-Nissen, J; Meyer, A S

2001-02-01

409

The role of omega-3 fatty acids in the secondary prevention of cardiovascular disease  

Microsoft Academic Search

Summary It has long been recognized from epidemiological studies that Greenland Eskimos have substantially reduced rates of acute myocardial infarction (MI) compared with Western controls. From these epidemiological observations, the benefits of fatty fish consumption have been explored in cell culture and animal studies, as well as randomized con- trolled trials investigating the cardioprotective effects of omega-3 fatty acids. Dietary

K. W. Lee; G. Y. H. LIP

2003-01-01

410

A laboratory study of covers made of low-sulphide tailings to prevent acid mine drainage  

Microsoft Academic Search

Covers with capillary barrier effects (CCBE) are considered to be one of the most effective ways to control acid mine drainage (AMD) production from mine wastes. The use of low-sulphide tailings in CCBE has been proposed recently for cases where other types of material may be unavailable near the mining site. This paper presents leaching column test results showing that

B. Bussière; M. Benzaazoua; M. Aubertin; M. Mbonimpa

2004-01-01

411

Cyclic GMP signaling in cardiomyocytes modulates fatty acid trafficking and prevents triglyceride accumulation  

Technology Transfer Automated Retrieval System (TEKTRAN)

While the balance between carbohydrates and fatty acids for energy production appears to be crucial for cardiac homeostasis, much remains to be learned about the molecular mechanisms underlying this relationship. Given the reported benefits of cGMP signaling on the myocardium, we investigated the im...

412

Helicobacter pylori infection prevents erosive reflux oesophagitis by decreasing gastric acid secretion  

Microsoft Academic Search

BACKGROUNDHelicobacter pylori infection is less prevalent and atrophic gastritis is less extensive in patients with reflux oesophagitis than those without it, but few studies have examined this relationship directly.AIMSWe investigated the relationship between H pylori infection, acid secretion, and reflux oesophagitis in Japanese subjects.SUBJECTSA total of 105 patients with erosive reflux oesophagitis were compared with 105 sex and age matched

T Koike; S Ohara; H Sekine; K Iijima; Y Abe; K Kato; T Toyota; T Shimosegawa

2001-01-01

413

PREVENTION OF ACID MINE DRAINAGE GENERATION FROM OPEN-PIT MINE HIGHWALLS  

EPA Science Inventory

Exposed, open pit mine highwalls contribute significantly to the production of acid mine drainage (AMD) thus causing environmental concerns upon closure of an operating mine. Available information on the generation of AMD from open-pit mine highwalls is very limit...

414

21 CFR 184.1187 - Calcium alginate.  

Code of Federal Regulations, 2013 CFR

...alginate (CAS Reg. No. 9005-35-0) is the calcium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Calcium alginate is prepared by the neutralization of purified alginic acid with appropriate pH control agents, or...

2013-04-01

415

21 CFR 184.1187 - Calcium alginate.  

Code of Federal Regulations, 2012 CFR

...alginate (CAS Reg. No. 9005-35-0) is the calcium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Calcium alginate is prepared by the neutralization of purified alginic acid with appropriate pH control agents, or...

2012-04-01

416

21 CFR 184.1187 - Calcium alginate.  

Code of Federal Regulations, 2010 CFR

...alginate (CAS Reg. No. 9005-35-0) is the calcium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Calcium alginate is prepared by the neutralization of purified alginic acid with appropriate pH control agents, or...

2010-04-01

417

21 CFR 184.1187 - Calcium alginate.  

Code of Federal Regulations, 2011 CFR

...alginate (CAS Reg. No. 9005-35-0) is the calcium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Calcium alginate is prepared by the neutralization of purified alginic acid with appropriate pH control agents, or...

2011-04-01

418

21 CFR 184.1187 - Calcium alginate.  

Code of Federal Regulations, 2014 CFR

...alginate (CAS Reg. No. 9005-35-0) is the calcium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Calcium alginate is prepared by the neutralization of purified alginic acid with appropriate pH control agents, or...

2014-04-01

419

Calcium phosphate deposition rate, structure and osteoconductivity on electrospun poly(l-lactic acid) matrix using electrodeposition or simulated body fluid incubation.  

PubMed

Mineralized nanofibrous scaffolds have been proposed as promising scaffolds for bone regeneration due to their ability to mimic both nanoscale architecture and chemical composition of natural bone extracellular matrix. In this study, a novel electrodeposition method was compared with an extensively explored simulated body fluid (SBF) incubation method in terms of the deposition rate, chemical composition and morphology of calcium phosphate formed on electrospun fibrous thin matrices with a fiber diameter in the range ~200-1400 nm prepared using 6, 8, 10 and 12 wt.% poly(l-lactic acid) (PLLA) solutions in a mixture of dichloromethane and acetone (2:1 in volume). The effects of the surface modification using the two mineralization techniques on osteoblastic cell (MC3T3-E1) proliferation and differentiation were also examined. It was found that electrodeposition was two to three orders of magnitude faster than the SBF method in mineralizing the fibrous matrices, reducing the mineralization time from ~2 weeks to 1h to achieve the same amounts of mineralization. The mineralization rate also varied with the fiber diameter but in opposite directions between the two mineralization methods. As a general trend, the increase of fiber diameter resulted in a faster mineralization rate for the electrodeposition method but a slower mineralization rate for the SBF incubation method. Using the electrodeposition method, one can control the chemical composition and morphology of the calcium phosphate by varying the electric deposition potential and electrolyte temperature to tune the mixture of dicalcium phosphate dihydrate and hydroxyapatite (HAp). Using the SBF method, one can only obtain a low crystallinity HAp. The mineralized electrospun PLLA fibrous matrices from either method similarly facilitate the proliferation and osteogenic differentiation of preosteoblastic MC3T3-E1 cells as compared to neat PLLA matrices. Therefore, the electrodeposition method can be utilized as a fast and versatile technique to fabricate mineralized nanofibrous scaffolds for bone tissue engineering. PMID:24012605

He, Chuanglong; Jin, Xiaobing; Ma, Peter X

2014-01-01

420

Calcium phosphate deposition rate, structure and osteoconductivity on electrospun poly(l-lactic acid) matrix using electrodeposition or simulated body fluid incubation  

PubMed Central

Mineralized nanofibrous scaffolds have been proposed as promising scaffolds for bone regeneration due to their ability to mimic both nanoscale architecture and chemical composition of natural bone extracellular matrix (ECM). In this study, a novel electrodeposition method was compared with an extensively explored simulated body fluid (SBF) incubation method in terms of the deposition rate, chemical composition, and morphology of calcium phosphate formed on electrospun fibrous thin matrices with a fiber diameter in the range from about 200 nm to about 1400 nm prepared using 6, 8, 10 and 12 wt% poly(l-lactic acid) (PLLA) solutions in a mixture of dichloromethane and acetone (2:1 in volume). The effects of the surface modification using the two mineralization techniques on osteoblastic cell (MC3T3-E1) proliferation and differentiation were also examined. It was found that electrodeposition was two to three orders of magnitude faster than the SBF method in mineralizing the fibrous matrices, reducing the mineralization time from about two weeks to an hour to achieve the same amounts of mineralization. The mineralization rate also varied with the fiber diameter but in opposite directions between the two mineralization methods. As a general trend, the increase of fiber diameter resulted in a faster mineralization rate for the electrodeposition method but a slower mineralization rate for the SBF incubation method. Using the electrodeposition method, one can control the chemical composition and morphology of the calcium phosphate by varying the electric deposition potential and electrolyte temperature to tune the mixture of dicalcium phosphate dihydrate (DCPD) and hydroxy apatite (HAp). Using the SBF method, one can only obtain a low crystallinity HAp. The mineralized electrospun PLLA fibrous matrices from either method similarly facilitate the proliferation and osteogenic differentiation of preosteoblastic MC3T3-E1 cells as compared to neat PLLA matrices. Therefore, the electrodeposition method can be utilized as a fast and versatile technique to fabricate mineralized nanofibrous scaffolds for bone tissue engineering. PMID:24012605

He, Chuanglong; Jin, Xiaobing; Ma, Peter X.

2013-01-01