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Sample records for calcium magnesium acetate

  1. 40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...

    Science.gov (United States)

    2010-07-01

    ...-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. 721.2076 Section 721...-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium... identified as D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...

  2. The effect of replacing aluminium hydroxide with calcium acetate/magnesium carbonate on serum phosphorus control in haemodialysis patients.

    Science.gov (United States)

    Arroyo, David; Panizo, Nayara; Abad, Soraya; Vega, Almudena; Pérez-de José, Ana; López-Gómez, Juan M

    2014-01-01

    Calcium acetate/magnesium carbonate (MgCO3) is a phosphorus binder with advantages in terms of cost, safety and tolerance and it has a similar efficacy to other drugs. The objective of the study is to assess the effects of replacing aluminium hydroxide [Al(OH3)] with MgCO3 on phosphorus and calcium metabolism in a cohort of haemodialysis patients. We included 21 patients with phosphorus magnesium, without short-term clinical significance. We do not know the effects of this increase in the longer term.

  3. Efficacy and safety of calcium acetate-magnesium carbonate in the treatment of hyperphosphatemia in dialysis patients.

    Science.gov (United States)

    Helal, Imed; Elkateb, Hanene; Hedri, Hafedh; Hajri, Malika; Hamida, Fethi Ben

    2016-01-01

    A phosphate binder combining calcium and magnesium offers an interesting therapeutic option to control hyperphosphatemia in dialysis patients. We investigated the effectiveness and tolerance of calcium acetate-magnesium carbonate (Ca-Mg). This is a 16-week prospective study including 16 dialysis patients. After an initial two-week washout period, serum phosphorus (sPho) ≥1.8 mmol/L, serum calcium (sCa) ≤2.6 mmol/L, and serum magnesium ≤1.5 mmol/L were the main inclusion criteria. The initial dose of Ca-Mg depended on sPho level and was titrated for every two weeks to have a sPho ≤ 1.8 mmol/L. A second two-week washout period followed the 12 weeks of treatment. Ca-Mg significantly reduced the mean sPho levels from 2.14 to 1.75 mmol/L by the end of the 12-week treatment period (P calcium carbonate, Ca-Mg might be a good alternative.

  4. Extracellular Calcium and Magnesium

    African Journals Online (AJOL)

    ABSTRACT. The cause of preeclampsia remains unknown and calcium and magnesium supplement are being suggested as means of prevention. The objective of this study was to assess magnesium and calcium in the plasma and cerebrospinal fluid of Nigerian women with preedamp sia and eclampsia. Setting was ...

  5. Magnesium, calcium and cancer

    National Research Council Canada - National Science Library

    Anghileri, Leopoldo J

    2009-01-01

    Magnesium ion (Mg(2+)) and calcium ion (Ca(2+)) control a diverse and important range of cellular processes, such as gene transcription, cell proliferation, neoplastic transformation, immune response and therapeutic treatment...

  6. Effects of calcium magnesium acetate on the combustion of coal-water slurries. Final project report, 1 September 1989--28 February 1993

    Energy Technology Data Exchange (ETDEWEB)

    Levendis, Y.A.; Wise, D.; Metghalchi, H.; Cumper, J.; Atal, A.; Estrada, K.R.; Murphy, B.; Steciak, J.; Hottel, H.C.; Simons, G.

    1993-07-01

    To conduct studies on the combustion of coal water fuels (CWFs) an appropriate facility was designed and constructed. The main components were (1) a high-temperature isothermal laminar flow furnace that facilitates observation of combustion events in its interior. The design of this system and its characterization are described in Chapter 1. (2) Apparatus for slurry droplet/agglomerate particle generation and introduction in the furnace. These devices are described in Chapters 1 and 3 and other attached publications. (3) An electronic optical pyrometer whose design, construction theory of operation, calibration and performance are presented in Chapter 2. (4) A multitude of other accessories, such as particle fluidization devices, a suction thermometer, a velocimeter, high speed photographic equipment, calibration devices for the pyrometer, etc., are described throughout this report. Results on the combustion of CWF droplets and CWF agglomerates made from micronized coal are described in Chapter 3. In the same chapter the combustion of CWF containing dissolved calcium magnesium acetate (CMA) axe described. The combustion behavior of pre-dried CWF agglomerates of pulverized grain coal is contrasted to that of agglomerates of micronized coal in Chapter 4. In the same chapter the combustion of agglomerates of carbon black and diesel soot is discussed as well. The effect of CMA on the combustion of the above materials is also discussed. Finally, the sulfur capture capability of CMA impregnated micronized and pulverized bituminous coals is examined in Chapter 5.

  7. Zinc, magnesium, and calcium ion supplementation confers tolerance to acetic acid stress in industrial Saccharomyces cerevisiae utilizing xylose.

    Science.gov (United States)

    Ismail, Ku Syahidah Ku; Sakamoto, Takatoshi; Hasunuma, Tomohisa; Zhao, Xin-Qing; Kondo, Akihiko

    2014-12-01

    Lignocellulosic biomass is a potential substrate for ethanol production. However, pretreatment of lignocellulosic materials produces inhibitory compounds such as acetic acid, which negatively affect ethanol production by Saccharomyces cerevisiae. Supplementation of the medium with three metal ions (Zn(2+) , Mg(2+) , and Ca(2+) ) increased the tolerance of S. cerevisiae toward acetic acid compared to the absence of the ions. Ethanol production from xylose was most improved (by 34%) when the medium was supplemented with 2 mM Ca(2+) , followed by supplementation with 3.5 mM Mg(2+) (29% improvement), and 180 μM Zn(2+) (26% improvement). Higher ethanol production was linked to high cell viability in the presence of metal ions. Comparative transcriptomics between the supplemented cultures and the control suggested that improved cell viability resulted from the induction of genes controlling the cell wall and membrane. Only one gene, FIT2, was found to be up-regulated in common between the three metal ions. Also up-regulation of HXT1 and TKL1 might enhance xylose consumption in the presence of acetic acid. Thus, the addition of ionic nutrients is a simple and cost-effective method to improve the acetic acid tolerance of S. cerevisiae. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Mixed calcium-magnesium pre-nucleation clusters enrich calcium

    OpenAIRE

    Verch, Andreas; Antonietti, Markus; Cölfen, Helmut

    2012-01-01

    It is demonstrated that magnesium and carbonate ions can form pre-nucleation clusters in analogy to calcium carbonate. If a mixed calcium and magnesium solution is brought in contact with carbonate ions, mixed pre-nucleation clusters form. The equilibrium constants for their formation are reported revealing that over the entire range of possible cation mixing ratios, calcium gets enriched over magnesium in the pre-nucleation clusters. This can explain high magnesium contents in amorphous calc...

  9. Comparison of Serum Calcium and Magnesium Between ...

    African Journals Online (AJOL)

    The present study compared serum calcium and magnesium in forty preeclamptic (cases) and forty normotensive (control) pregnant women matched for age, parity, and socioeconomic status. Serum calcium and magnesium levels were measured using atomic absorption spectrophotometer. Statistical analysis was done ...

  10. Magnesium and Calcium in Isolated Cell Nuclei

    Science.gov (United States)

    Naora, H.; Naora, H.; Mirsky, A. E.; Allfrey, V. G.

    1961-01-01

    The calcium and magnesium contents of thymus nuclei have been determined and the nuclear sites of attachment of these two elements have been studied. The nuclei used for these purposes were isolated in non-aqueous media and in sucrose solutions. Non-aqueous nuclei contain 0.024 per cent calcium and 0.115 per cent magnesium. Calcium and magnesium are held at different sites. The greater part of the magnesium is bound to DNA, probably to its phosphate groups. Evidence is presented that the magnesium atoms combined with the phosphate groups of DNA are also attached to mononucleotides. There is reason to believe that those DNA-phosphate groups to which magnesium is bound, less than 1/10th of the total, are metabolically active, while those to which histones are attached seem to be inactive. PMID:13727745

  11. Removal of Oil Spills from Salt Water by Magnesium, Calcium ...

    African Journals Online (AJOL)

    Magnesium, calcium carbonates and oxides that are widely used in cement industries were employed in studying sorption of petroleum oil spills from salt water at different condition parameters such as temperature, loading weight, degree of salinity. Treatment of magnesium, calcium carbonates and oxides by dodecyl ...

  12. Serum magnesium, phosphate and calcium in Nigerian children with ...

    African Journals Online (AJOL)

    of sickle cell disease. This study was set out to determine the serum levels of magnesium, phosphorus and calcium in Nigerian children with sickle cell disease. Study design.' A case-control study carried out on children with HbSS genotype (cases) and age—matched controls with HbAA. Serum magnesium, calcium,.

  13. Extracellular Calcium and Magnesium in Preeclampsia and Eclampsia

    African Journals Online (AJOL)

    The cause of preeclampsia remains unknown and calcium and magnesium supplement are being suggested as means of prevention. The objective of this study was to assess magnesium and calcium in the plasma and cerebrospinal fluid of Nigerian women with preeclampsia and eclampsia. Setting was University of ...

  14. Characterization of a process for the in-furnace reduction of NOx, SO2, and HCl by carboxylic salts of calcium

    OpenAIRE

    Nimmo, W.; Patsias, A.A.; Hall, W.J.

    2005-01-01

    Calcium magnesium acetate has been assessed as an agent for the reduction of NOx, SO2, and HCl, at the pilot scale, in a down-fired combustor operating at 80 kWth. In addition to this, the chemical and physical processes that occur during heating have been investigated. Benchmarking of calcium magnesium acetate with a suite of five other carboxylic salts (calcium magnesium acetate, calcium propionate, calcium acetate, calcium benzoate, magnesium acetate, and calcium formate) has been performe...

  15. Magnesium: Origin and role in calcium-treated inclusions

    CSIR Research Space (South Africa)

    Pistorius, CP

    2006-08-01

    Full Text Available in calcium-treated steel is not fully clear, nor is the origin of the several percent of magnesium oxide that is often present in calcium-treated inclusions. To study this, steel was sampled after calcium treatment at an industrial steel plant...

  16. Magnesium supplement in pregnancy-induced hypertension: effects on maternal and neonatal magnesium and calcium homeostasis

    DEFF Research Database (Denmark)

    Rudnicki, M; Frølich, A; Fischer-Rasmussen, W

    1991-01-01

    loss of magnesium. Serum level and the urinary excretion of magnesium returned to pretreatment level at delivery. Maternal magnesium supplement increased the concentrations of magnesium in umbilical cord and neonatal blood 1 day after delivery. Serum ionized calcium did not change during the study......The objective of this study was to evaluate the effect of low dose magnesium supplement upon maternal and fetal serum levels of mineral status in pregnancies complicated with hypertension (PIH). Twenty-five patients with PIH agreed to participate and were randomly allocated, in a double...

  17. Relation of urinary calcium and magnesium excretion to blood pressure

    DEFF Research Database (Denmark)

    Kesteloot, Hugo; Tzoulaki, Ioanna; Brown, Ian J

    2011-01-01

    Data indicate an inverse association between dietary calcium and magnesium intakes and blood pressure (BP); however, much less is known about associations between urinary calcium and magnesium excretion and BP in general populations. The authors assessed the relation of BP to 24-hour excretion...... of calcium and magnesium in 2 cross-sectional studies. The International Study of Macro- and Micro-Nutrients and Blood Pressure (INTERMAP) comprised 4,679 persons aged 40-59 years from 17 population samples in China, Japan, the United Kingdom, and the United States, and the International Cooperative Study......) of higher urinary calcium excretion (associations were smaller for diastolic BP) in INTERMAP. Qualitatively similar associations were observed in INTERSALT analyses. Associations between magnesium excretion and BP were small and nonsignificant for most of the models examined. The present data suggest...

  18. Elemental calcium intake associated with calcium acetate/calcium carbonate in the treatment of hyperphosphatemia.

    Science.gov (United States)

    Wilson, Rosamund J; Copley, J Brian

    2017-01-01

    Calcium-based and non-calcium-based phosphate binders have similar efficacy in the treatment of hyperphosphatemia; however, calcium-based binders may be associated with hypercalcemia, vascular calcification, and adynamic bone disease. A post hoc analysis was carried out of data from a 16-week, Phase IV study of patients with end-stage renal disease (ESRD) who switched to lanthanum carbonate monotherapy from baseline calcium acetate/calcium carbonate monotherapy. Of the intent-to-treat population (N=2520), 752 patients with recorded dose data for calcium acetate (n=551)/calcium carbonate (n=201) at baseline and lanthanum carbonate at week 16 were studied. Elemental calcium intake, serum phosphate, corrected serum calcium, and serum intact parathyroid hormone levels were analyzed. Of the 551 patients with calcium acetate dose data, 271 (49.2%) had an elemental calcium intake of at least 1.5 g/day at baseline, and 142 (25.8%) had an intake of at least 2.0 g/day. Mean (95% confidence interval [CI]) serum phosphate levels were 6.1 (5.89, 6.21) mg/dL at baseline and 6.2 (6.04, 6.38) mg/dL at 16 weeks; mean (95% CI) corrected serum calcium levels were 9.3 (9.16, 9.44) mg/dL and 9.2 (9.06, 9.34) mg/dL, respectively. Of the 201 patients with calcium carbonate dose data, 117 (58.2%) had an elemental calcium intake of at least 1.5 g/day, and 76 (37.8%) had an intake of at least 2.0 g/day. Mean (95% CI) serum phosphate levels were 5.8 (5.52, 6.06) mg/dL at baseline and 5.8 (5.53, 6.05) mg/dL at week 16; mean (95% CI) corrected serum calcium levels were 9.7 (9.15, 10.25) mg/dL and 9.2 (9.06, 9.34) mg/dL, respectively. Calcium acetate/calcium carbonate phosphate binders, taken to control serum phosphate levels, may result in high levels of elemental calcium intake. This may lead to complications related to calcium balance.

  19. Pattern of serum total calcium, magnesium and zinc in human ...

    African Journals Online (AJOL)

    Serum total calcium, magnesium and zinc were analysed using atomic absorption spectrophotometry and HIV tests were carried out on each of the subjects. There was no significant gender difference in the mean values of serum total calcium, magnessium and Zinc obtained from the HIV disease/AIDS seropositive females ...

  20. Corrosion Behavior of PEO Coatings Formed on AZ31 Alloy in Phosphate-Based Electrolytes with Calcium Acetate Additive

    Science.gov (United States)

    Ziyaei, E.; Atapour, M.; Edris, H.; Hakimizad, A.

    2017-07-01

    The PEO coating started on magnesium AZ31 using a unipolar DC power source. The coating was generated in the electrolyte based on Na3PO4·12H2O and KOH with calcium acetate as additive. The x-ray diffraction method showed some phases containing calcium and phosphate, which was created in the presence of additive. Also, the EDS tests of the sample's surfaces proved the existence of calcium on the surface. Based on the electrochemical tests results, the most corrosion resistance belongs to the sample with calcium acetate additive. In fact, the results of the EIS tests showed the coating with calcium acetate has the highest resistance but the lowest capacitance. However, this state belongs to the surface morphology, the lower porosity, and surface chemical composition.

  1. Calcium, potassium and magnesium treatment of Chrysanthemum morifolium cv. "Bi Time" and callogenesis in vitro

    Directory of Open Access Journals (Sweden)

    Borgatto Fábio

    2002-01-01

    Full Text Available The chemical composition and vegetative vigor of the donor plant are essential for the satisfactory performance of explants in vitro. In order to test the effect of potassium, calcium and magnesium nutritional status of Chrysanthemum morifolium plants on callogenesis in vitro, pot plants growing in sand were irrigated with nutrient solution containing different levels of potassium (0; 58.5; 117 and 234 mg L-1, calcium (0; 50; 100 e 200 mg L-1 and magnesium (0;12; 48 e 96 mg L-1. After 30 and 45 days, explants (shoot segments and leaf discs were collected, desinfected and inoculated on MS solid medium supplemented with 0.1 mg L-1 of kinetin and 5.0 mg L-1 of nafthalene acetic acid for callogenesis induction. Callogenesis evaluated as callus fresh weight was affected by nutrients treatment. Callus growth on leaf explants was inversely proporcional to potassium concentration and directly proportional to magnesium concentration in shoot explants. The calcium effect on callogensis of leaf explants was dependent on treatment duration. For 30 days treatment callogenseis was inversely related to calcium concentration and after 45 days was directly related to calcium concentration.

  2. Renal control of calcium, phosphate, and magnesium homeostasis.

    Science.gov (United States)

    Blaine, Judith; Chonchol, Michel; Levi, Moshe

    2015-07-07

    Calcium, phosphate, and magnesium are multivalent cations that are important for many biologic and cellular functions. The kidneys play a central role in the homeostasis of these ions. Gastrointestinal absorption is balanced by renal excretion. When body stores of these ions decline significantly, gastrointestinal absorption, bone resorption, and renal tubular reabsorption increase to normalize their levels. Renal regulation of these ions occurs through glomerular filtration and tubular reabsorption and/or secretion and is therefore an important determinant of plasma ion concentration. Under physiologic conditions, the whole body balance of calcium, phosphate, and magnesium is maintained by fine adjustments of urinary excretion to equal the net intake. This review discusses how calcium, phosphate, and magnesium are handled by the kidneys. Copyright © 2015 by the American Society of Nephrology.

  3. Magnesium: Effect on ocular health as a calcium channel antagonist

    Directory of Open Access Journals (Sweden)

    Şafak Korkmaz

    2013-06-01

    Full Text Available Magnesium is the physiologic calcium channel blocker,involving in many different metabolic processes by maintainingcell membrane function, modulating smooth musclecontraction and influencing enzymatic activities. Magnesiumhas been shown to increase blood flow to tissuesby modifying endothelial function via endothelin-1 (ET-1and nitric Oxide (NO pathways. Magnesium also exhibitsneuroprotective role by blocking N-methyl-D-aspartate(NMDA receptor related calcium influx and by inhibitingthe release of glutamate, hence protects the cell againstoxidative stress and apoptosis. Both increase in bloodflow and its neuroprotective effect make magnesium agood candidate for glaucoma studies. Magnesium hasbeen shown to decrease oxidative stress and apoptosisin retinal tissue and to have retinal ganglion cell sparingeffect. A series of studies has been conducted aboutmagnesium could decrease insulin resistance in diabeticpatients, ease glycemia control and prevent diabetic retinopathy.Magnesium is found to be critically important inmaintaining normal ionic homeostasis of lens. Magnesiumdeficiency has been shown to cause increased lenticularoxidative stress and ionic imbalance in the lens so triggercataractogenesis. J Clin Exp Invest 2013; 4 (2: 244-251Key words: Magnesium, calcium channel blockage,glaucoma, neuroprotection, diabetic retinopathy, cataract

  4. Studies on calcium, magnesium and sulphate in the Mandovi and Zuari river system (Goa)

    Digital Repository Service at National Institute of Oceanography (India)

    SenGupta, R.; Naik, S.

    Distribution of calcium, magnesium and sulphate have been examined in the tide-dominated Mandovi and Zuari river systems. Calcium and magnesium appear to take some part in the bio-geochemical cycles of the rivers and behave as semi...

  5. Abnormalities of serum calcium and magnesium

    Science.gov (United States)

    Neonatal hypocalcemia is defined as a total serum calcium concentration of <7 mg/dL or an ionized calcium concentration of <4 mg/dL (1mmol/L). In very low birth weight (VLBW) infants, ionized calcium values of 0.8 to 1 mmol/L are common and not usually associated with clinical symptoms. In larger in...

  6. Calcium and Magnesium Metabolism in Pre-Eclampsia.

    Science.gov (United States)

    Udenze, I C; Arikawe, A P; Azinge, E C; Okusanya, B O; Ebuehi, O A

    2014-01-01

    Preeclampsia is a multisystem disorder associated with high maternal and perinatal mortality and morbidity. The cause of the disorder is largely unknown and its pathogenesis is complex and poorly understood. Calcium and magnesium are divalent ions which may have roles to play in the manifestations of the disease. An understanding of their metabolism in preeclampsia may aid our management of pregnant women who develop the disease. To determine the plasma and urinary concentrations of calcium, magnesium and parathyroid hormone in women with mild, severe preeclampsia and in normal pregnancy. This is was a case control study of fifty women with mild preeclampsia, fifty women with severe preeclampsia and fifty women with normal pregnancy as controls, drawn from The Antenatal Clinic at the Lagos University Teaching Hospital, Lagos, Nigeria. The women were consecutively recruited after signing an informed consent form. Ethical approval was obtained from the medical ethics committee of the hospital. The three groups of women were similar in their socio demographic characteristics. Plasma calcium was low in mild and severe preeclampsia compared to normal pregnancy controls (p=0.021). Urine calcium/creatinine ratio was lower in mild and severe preeclampsia compared to normal pregnancy controls (p= 0.030). Fractional excretion of calcium and levels of parathyroid hormone were similar across all three subgroups of women. Plasma magnesium was higher in mild and severe preeclampsia compared to normal pregnancy controls (p=0.011) and showed a positive correlation with plasma creatinine (r=0.48, p=0.045). Parathyroid hormone levels were similar across the study groups. Preeclampsia is associated with significant changes in calcium and magnesium metabolism. This study noted significant hypocalcaemia in mild and severe preeclampsia with significantly low urine calcium/creatinine levels. Calcium supplementation may have a place in patient's management. Hypermagnesemia was observed in

  7. in human sperm motility and level of calcium and magnesium

    African Journals Online (AJOL)

    J. Valsa

    2015-11-06

    Nov 6, 2015 ... Abstract A detailed sperm motility study for 24 h after collection was done. The level of calcium and magnesium in seminal plasma during this period was also seen to understand the role of these electrolytes on sperm motility. Good care was taken in selection of subjects (young and healthy), collection and ...

  8. Influence of calcium and magnesium based fertilizers on fungal ...

    African Journals Online (AJOL)

    Notwithstanding the important roles of calcium and magnesium ions in plant growth and development,the use of fertilizers containing them is not yet a common agricultural practice in Cameroon. Such fertilizers were applied on the soil and leaves of three most cultivated varieties of tomato in the Western Highlands of ...

  9. Magnesium, calcium and phosphorus in the intensive care unit: Do ...

    African Journals Online (AJOL)

    Magnesium, calcium and phosphorus are important electrolytes involved in the regulation of homeostasis. However the utility in monitoring them in critically ill patients is still unclear. We therefore undertook a prospective, non-interventional, single center study in the intensive care unit of a tertiary care hospital in ...

  10. influence of calcium and magnesium based fertilizers on fungal

    African Journals Online (AJOL)

    PUBLICATIONS1

    Magnesium that activates many dehy- drogenases and phosphate transfer enzymes. (Öpik and Rolfe, 2005) may stimulate the ef- fects of calcium and/or ABA on fruit yield since ABA regulates fruit maturation, seed stor- age reserve accumulation and induces protein synthesis in seeds (Davies, 2007; Taiz and. Zeiger, 2006).

  11. Comparative study on calcium, magnesium and cobalt in diabetic ...

    African Journals Online (AJOL)

    Comparative study on calcium, magnesium and cobalt in diabetic and non diabetic patients (males) in Punjab, Pakistan. ... The mineral elements in the serum were analyzed by using atomic absorption spectrophotometer. The results depicted that the diabetic patients had higher mean concentration of Ca (141.47 ppm), Mg ...

  12. Boron, calcium and magnesium in Kavaratti lagoon water, Lakshadweep Archipelago

    Digital Repository Service at National Institute of Oceanography (India)

    Nasnolkar, C.M.; Salkar, V.R.; Shirodkar, P.V.; Abidi, S.A.H.

    1228.8 to 1319.8 mg kg sup(-1) (av. 1280.19 mg kg sup(-1)) and the salinity varied from 35.01 to 35.10 x 10 sup(-3) (av. 35.04 x 10 sup(-3)). The ratios of boron, calcium and magnesium to chlorinity in the lagoon water showed wide variation and were...

  13. influence of calcium and magnesium based fertilizers on fungal

    African Journals Online (AJOL)

    PUBLICATIONS1

    ABSTRACT. Notwithstanding the important roles of calcium and magnesium ions in plant growth and devel- opment, the use of fertilizers containing them is not yet a common agricultural practice in Cam- eroon. Such fertilizers were applied on the soil and leaves of three most cultivated varieties of tomato in the Western ...

  14. A study of serum magnesium, calcium and phosphorus level, and ...

    African Journals Online (AJOL)

    A study of serum magnesium, calcium and phosphorus level, and cognition in the elderly population of South India. ... Macronutrients have been involved in many metabolic activities of the body including oxidation and reduction reactions in the central nervous system. This involvement of macronutrients in the activities of ...

  15. Comparison of Serum Calcium and Magnesium Between ...

    African Journals Online (AJOL)

    that serum magnesium seems to play a crucial role in the pathophysiology of preeclampsia in ... mechanism is characterized with the failure of the trophoblastic invasion of the spiral arteries, ... of the disease. Other contributory factors include obesity, ... the management of preeclampsia with nutritional approach in relation to ...

  16. Comparison of Serum Calcium and Magnesium Between ...

    African Journals Online (AJOL)

    and preeclampsia, commonly associated with increased maternal and infant mortality and morbidity.[1] Preeclampsia is a progressive, multi-systemic disorder characterized ... that serum magnesium seems to play a crucial role in the pathophysiology of preeclampsia in ..... Prevention of preeclampsia: A big disappointment.

  17. The Role of Magnesium and Calcium in Governing Yeast Agglomeration

    Directory of Open Access Journals (Sweden)

    Rosslyn M. Birch

    2002-01-01

    Full Text Available »Grit« formation by agglomerating cells of baker’s yeast is an idiosyncratic phenomenon of irreversible cellular aggregation that is detrimental to yeast quality. Agglomeration results in failure of rehydrated dried yeast to evenly resuspend and has economic consequences for both yeast manufacturers and bakers. Several environmental factors are implicated in governing yeast agglomeration, but no significant differences between 'gritty' and 'non-gritty' yeast in terms of cell hydrophobicity or flocculence have been reported. In this study, analysis of cellular metal ions has revealed high levels of calcium in 'gritty' strains of Saccharomyces cerevisiae, which suggests that calcium ions may positively influence agglomeration. In contrast, it was found that cellular magnesium levels were higher in 'non-gritty' yeast. Furthermore, by increasing magnesium concentrations in molasses yeast growth media, a reduction in cellular calcium was observed and this concomitantly reduced the tendency of cells to agglomerate and form grit. Magnesium thus acted antagonistically against calcium-induced agglomeration, possibly by blocking calcium binding to yeast cell surface receptors. Results suggested that yeast agglomeration and metal ion bioavailability were inextricably linked and the findings are discussed in relation to possible measures of alleviating cellular agglomeration in the production of baker’s yeast.

  18. Bioactivity studies of calcium magnesium silicate prepared from eggshell waste by sol–gel combustion synthesis

    Directory of Open Access Journals (Sweden)

    Rajan Choudhary

    2015-06-01

    Full Text Available The present study focused on the synthesis of calcium magnesium silicate (akermanite, Ca2MgSi2O7 using eggshell biowaste (as calcium source, magnesium nitrate and tetraethyl orthosilicate (TEOS as starting materials. Sol–gel combustion method was adopted to obtain calcium magnesium silicate. Citric acid was used as a fuel (reducing agent and nitrate ions present in the metal nitrates acts as an oxidizing agent during combustion process. The characterization of synthesized calcium magnesium silicate was carried out by powder X-ray diffraction (XRD, Fourier transform infrared (FTIR and scanning electron microscopy (SEM techniques. Calcium magnesium silicate crystallite size was observed in nano regime which can effectively mimic natural bone apatite composition. In-vitro bioactivity was investigated by immersing calcium magnesium silicate pellet in simulated body fluid (SBF for three weeks. Results show effective deposition of crystallized hydroxyapatite (HAP layer on its surface and predicting its possibilities for applications in hard tissue regeneration.

  19. Enzymatic, urease-mediated mineralization of gellan gum hydrogel with calcium carbonate, magnesium-enriched calcium carbonate and magnesium carbonate for bone regeneration applications

    DEFF Research Database (Denmark)

    Douglas, Timothy E L; Łapa, Agata; Samal, Sangram Keshari

    2017-01-01

    Mineralization of hydrogel biomaterials is considered desirable to improve their suitability as materials for bone regeneration. Calcium carbonate (CaCO3 ) has been successfully applied as a bone regeneration material, but hydrogel-CaCO3 composites have received less attention. Magnesium (Mg) has...... enzymatically with CaCO3 , Mg-enriched CaCO3 and magnesium carbonate to generate composite biomaterials for bone regeneration. Hydrogels loaded with the enzyme urease were mineralized by incubation in mineralization media containing urea and different ratios of calcium and magnesium ions. Increasing...... the magnesium concentration decreased mineral crystallinity. At low magnesium concentrations calcite was formed, while at higher concentrations magnesian calcite was formed. Hydromagnesite (Mg5 (CO3 )4 (OH)2 .4H2 O) formed at high magnesium concentration in the absence of calcium. The amount of mineral formed...

  20. The characterisation of organic components in the calcium and magnesium effluent streams at Sappi Saiccor

    National Research Council Canada - National Science Library

    Moodley, B; Marsh, J.J; Mulholland, D.A

    2003-01-01

    .... The major constituents identified in the calcium effluent stream and the magnesium condensate effluent stream were a mixture of lignan isomers, episyringaresinol and meso-syringaresinol and lignin...

  1. Magnesium substitution in the structure of orthopedic nanoparticles: A comparison between amorphous magnesium phosphates, calcium magnesium phosphates, and hydroxyapatites.

    Science.gov (United States)

    Nabiyouni, Maryam; Ren, Yufu; Bhaduri, Sarit B

    2015-01-01

    As biocompatible materials, magnesium phosphates have received a lot of attention for orthopedic applications. During the last decade multiple studies have shown advantages for magnesium phosphate such as lack of cytotoxicity, biocompatibility, strong mechanical properties, and high biodegradability. The present study investigates the role of Mg(+2) and Ca(+2) ions in the structure of magnesium phosphate and calcium phosphate nanoparticles. To directly compare the effect of Mg(+2) and Ca(+2) ions on structure of nanoparticles and their biological behavior, three groups of nanoparticles including amorphous magnesium phosphates (AMPs) which release Mg(+2), calcium magnesium phosphates (CMPs) which release Mg(+2) and Ca(+2), and hydroxyapatites (HAs) which release Ca(+2) were studied. SEM, TEM, XRD, and FTIR were used to evaluate the morphology, crystallinity, and chemical properties of the particles. AMP particles were homogeneous nanospheres, whereas CMPs were combinations of heterogeneous nanorods and nanospheres, and HAs which contained heterogeneous nanosphere particles. Cell compatibility was monitored in all groups to determine the cytotoxicity effect of particles on studied MC3T3-E1 preosteoblasts. AMPs showed significantly higher attachment rate than the HAs after 1 day and both AMPs and CMPs showed significantly higher proliferation rate when compared to HAs after 7days. Gene expression level of osteoblastic markers ALP, COL I, OCN, OPN, RUNX2 were monitored and they were normalized to GAPDH housekeeping gene. Beta actin expression level was monitored as the second housekeeping gene to confirm the accuracy of results. In general, AMPs and CMPs showed higher expression level of osteoblastic genes after 7 days which can further confirm the stimulating role of Mg(+2) and Ca(+2) ions in increasing the proliferation rate, differentiation, and mineralization of MC3T3-E1 preosteoblasts. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Calcium acetate or calcium carbonate for hyperphosphatemia of hemodialysis patients: a meta-analysis.

    Science.gov (United States)

    Wang, Yong; Xie, Guoqiang; Huang, Yuanhang; Zhang, Han; Yang, Bo; Mao, Zhiguo

    2015-01-01

    High levels of serum phosphorus both at baseline and during follow-up are associated with increased mortality in dialysis patients, and administration of phosphate binders was independently associated with improved survival among hemodialysis population. Calcium-based phosphate binders are the most commonly used phosphate binders in developing countries for their relatively low costs. To compare the efficacy and safety between calcium carbonate and calcium acetate in the treatment of hyperphosphatemia in hemodialysis patients. PubMed, EMBASE, Cochrane Library, Google scholar and Chinese databases (Wanfang, Weipu, National Knowledge Infrastructure of China) were searched for relevant studies published before March 2014. Reference lists of nephrology textbooks and review articles were checked. A meta-analysis of randomized controlled trials (RCTs) and quasi-RCTs that assessed the effects and adverse events of calcium acetate and calcium carbonate in adult patients with MHD was performed using Review Manager 5.0. A total of ten studies (625 participants) were included in this meta-analysis. There was insufficient data in all-cause mortality and cardiovascular events for meta-analysis. Compared with calcium carbonate group, the serum phosphorus was significantly lower in calcium acetate group after4 weeks' administration (MD -0.15 mmol/L, 95% CI -0.28 to -0.01) and after 8 weeks' administration (MD -0.25 mmol/L, 95% CI -0.40 to -0.11). There was no difference in serum calcium levels or the incidence of hypercalcemia between two groups at 4 weeks and 8 weeks. No statistical difference was found in parathyroid hormone (PTH) levels or serum calcium by phosphorus (Ca x P) product. There was significantly higher risk of intolerance with calcium acetate treatment (RR 3.46, 95% CI 1.48 to 8.26). For hyperphosphatemia treatment, calcium acetate showed better efficacy and with a higher incidence of intolerance compared with calcium carbonate. There are insufficient data to

  3. Impact of magnesium:calcium ratio on calcification of the aortic wall.

    Science.gov (United States)

    Villa-Bellosta, Ricardo

    2017-01-01

    An inverse relationship between serum magnesium concentration and vascular calcification has been reported following observational clinical studies. Moreover, several studies have been suggesting a protective effect of magnesium on the vascular calcification. However, the exact mechanism remains elusive, and investigators have speculated among a myriad of potential actions. The effect of magnesium on calcification of the aortic wall is yet to be investigated. In the present study, the effects of magnesium and calcium on the metabolism of extracellular PPi, the main endogenous inhibitor of vascular calcification, were investigated in the rat aorta. Calcium and magnesium have antagonist effects on PPi hydrolysis in the aortic wall. Km and Ki values for PPi hydrolysis in rat aortic rings were 1.1 mmol/L magnesium and 32 μmol/L calcium, respectively, but ATP hydrolysis was not affected with calcium. Calcium deposition in the rat aortic wall dramatically increased when the magnesium concentration was increased (ratio of Mg:Ca = 1:1; 1.5 mmol/L calcium and 1.5 mmol/L magnesium) respect to low magnesium concentration (ratio Mg:Ca = 1:3, 1.5 mmol/L calcium and 0.75 mmol/L magnesium). Data from observational clinical studies showing that the serum magnesium concentration is inversely correlated with vascular calcification could be reinterpreted as a compensatory regulatory mechanism that reduces both PPi hydrolysis and vascular calcification. The impact of magnesium in vascular calcification in humans could be studied in association with calcium levels, for example, as the magnesium:calcium ratio.

  4. Increased renal calcium and magnesium transporter abundance in streptozotocin-induced diabetes mellitus.

    Science.gov (United States)

    Lee, C-T; Lien, Y-H H; Lai, L-W; Chen, J-B; Lin, C-R; Chen, H-C

    2006-05-01

    Diabetes is associated with renal calcium and magnesium wasting, but the molecular mechanisms of these defects are unknown. We measured renal calcium and magnesium handling and investigated the effects of diabetes on calcium and magnesium transporters in the thick ascending limb and distal convoluted tubule in streptozotocin (STZ)-induced diabetic rats. Rats were killed 2 weeks after inducing diabetes, gene expression of calcium and magnesium transporters in the kidney was determined by real-time polymerase chain reaction, and the abundance of protein was assessed by immunoblotting. Our results showed that diabetic rats had significant increase in the fractional excretion for calcium and magnesium (both P diabetic rats. Sodium chloride cotransporter was also increased (207 +/- 10%). No change was found in paracellin-1 (cortex: 108 +/- 8%; medulla: 110 +/- 10%). Immunofluorescent studies of renal sections showed significant increase in calbindin-D28k (238 +/- 10%) and TRPV5 (211 +/- 10%), but no changes in paracellin-1 in Western blotting (cortex: 110 +/- 7%; medulla: 99 +/- 7%). Insulin administration completely corrected the hyperglycemia-associated hypercalciuria and hypermagnesiuria, and reversed the increase of calcium and magnesium transporter abundance. In conclusion, our results demonstrated increased renal calcium and magnesium transporter abundance in STZ-induced diabetic rats, which may represent a compensatory adaptation for the increased load of calcium and magnesium to the distal tubule.

  5. Importance of calcium and magnesium in water - water hardening

    Science.gov (United States)

    Barloková, D.; Ilavský, J.; Kapusta, O.; Šimko, V.

    2017-10-01

    Basic information about importance of calcium and magnesium in water, about their properties, effect to human health, problems what can cause under the lower ( 5 mmol/L) concentrations in water supply distribution systems, the most commonly used methods of water hardening are presented. The article contains the water hardening results carried out during the pilot plant experiments in WTP Hriňová and WTP Turček. For water hardening, treated water at the end of the process line, i.e., after coagulation, sedimentation and filtration, saturated with CO2 and filtrated through half-burnt dolomite material (PVD) was used. The results show that the filtration rate is 17.1 m/h in the case of WTP Hriňová and 15.2 m/h in the case of WTP Turček to achieve the recommended concentration of Ca and Mg in the treated water after the addition of CO2 and filtration through PVD. The longer the water contact time with PVD (depending on the CO2 content), the more water is enriched with magnesium, but the calcium concentration has not so much increased.

  6. Magnesium supplementation through seaweed calcium extract rather than synthetic magnesium oxide improves femur bone mineral density and strength in ovariectomized rats.

    Science.gov (United States)

    Bae, Yun Jung; Bu, So Young; Kim, Jae Young; Yeon, Jee-Young; Sohn, Eun-Wha; Jang, Ki-Hyo; Lee, Jae-Cheol; Kim, Mi-Hyun

    2011-12-01

    Commercially available seaweed calcium extract can supply high amounts of calcium as well as significant amounts of magnesium and other microminerals. The purpose of this study was to investigate the degree to which the high levels of magnesium in seaweed calcium extract affects the calcium balance and the bone status in ovariectomized rats in comparison to rats supplemented with calcium carbonate and magnesium oxide. A total of 40 Sprague-Dawley female rats (7 weeks) were divided into four groups and bred for 12 weeks: sham-operated group (Sham), ovariectomized group (OVX), ovariectomized with inorganic calcium and magnesium supplementation group (OVX-Mg), and ovariectomized with seaweed calcium and magnesium supplementation group (OVX-SCa). All experimental diets contained 0.5% calcium. The magnesium content in the experimental diet was 0.05% of the diet in the Sham and OVX groups and 0.1% of the diet in the OVX-Mg and OVX-SCa groups. In the calcium balance study, the OVX-Mg and OVX-SCa groups were not significantly different in calcium absorption compared to the OVX group. However, the femoral bone mineral density and strength of the OVX-SCa group were higher than those of the OVX-Mg and OVX groups. Seaweed calcium with magnesium supplementation or magnesium supplementation alone did not affect the serum ALP and CTx levels in ovariectomized rats. In summary, consumption of seaweed calcium extract or inorganic calcium carbonate with magnesium oxide demonstrated the same degree of intestinal calcium absorption, but only the consumption of seaweed calcium extract resulted in increased femoral bone mineral density and strength in ovariectomized rats. Our results suggest that seaweed calcium extract is an effective calcium and magnesium source for improving bone health compared to synthetic calcium and magnesium supplementation.

  7. Calcium orthophosphate coatings on magnesium and its biodegradable alloys.

    Science.gov (United States)

    Dorozhkin, Sergey V

    2014-07-01

    Biodegradable metals have been suggested as revolutionary biomaterials for bone-grafting therapies. Of these metals, magnesium (Mg) and its biodegradable alloys appear to be particularly attractive candidates due to their non-toxicity and as their mechanical properties match those of bones better than other metals do. Being light, biocompatible and biodegradable, Mg-based metallic implants have several advantages over other implantable metals currently in use, such as eliminating both the effects of stress shielding and the requirement of a second surgery for implant removal. Unfortunately, the fast degradation rates of Mg and its biodegradable alloys in the aggressive physiological environment impose limitations on their clinical applications. This necessitates development of implants with controlled degradation rates to match the kinetics of bone healing. Application of protective but biocompatible and biodegradable coatings able to delay the onset of Mg corrosion appears to be a reasonable solution. Since calcium orthophosphates are well tolerated by living organisms, they appear to be the excellent candidates for such coatings. Nevertheless, both the high chemical reactivity and the low melting point of Mg require specific parameters for successful deposition of calcium orthophosphate coatings. This review provides an overview of current coating techniques used for deposition of calcium orthophosphates on Mg and its biodegradable alloys. The literature analysis revealed that in all cases the calcium orthophosphate protective coatings both increased the corrosion resistance of Mg-based metallic biomaterials and improved their surface biocompatibility. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  8. Magnesium substitution in the structure of orthopedic nanoparticles: A comparison between amorphous magnesium phosphates, calcium magnesium phosphates, and hydroxyapatites

    Energy Technology Data Exchange (ETDEWEB)

    Nabiyouni, Maryam, E-mail: maryam.nabiyouni@rockets.utoledo.edu [Department of Bioengineering, University of Toledo, Toledo, OH (United States); Ren, Yufu [Department of Mechanical, Industrial and Manufacturing Engineering, University of Toledo, Toledo, OH (United States); Bhaduri, Sarit B. [Department of Mechanical, Industrial and Manufacturing Engineering, University of Toledo, Toledo, OH (United States); Department of Surgery (Dentistry), University of Toledo, Toledo, OH (United States)

    2015-07-01

    As biocompatible materials, magnesium phosphates have received a lot of attention for orthopedic applications. During the last decade multiple studies have shown advantages for magnesium phosphate such as lack of cytotoxicity, biocompatibility, strong mechanical properties, and high biodegradability. The present study investigates the role of Mg{sup +2} and Ca{sup +2} ions in the structure of magnesium phosphate and calcium phosphate nanoparticles. To directly compare the effect of Mg{sup +2} and Ca{sup +2} ions on structure of nanoparticles and their biological behavior, three groups of nanoparticles including amorphous magnesium phosphates (AMPs) which release Mg{sup +2}, calcium magnesium phosphates (CMPs) which release Mg{sup +2} and Ca{sup +2}, and hydroxyapatites (HAs) which release Ca{sup +2} were studied. SEM, TEM, XRD, and FTIR were used to evaluate the morphology, crystallinity, and chemical properties of the particles. AMP particles were homogeneous nanospheres, whereas CMPs were combinations of heterogeneous nanorods and nanospheres, and HAs which contained heterogeneous nanosphere particles. Cell compatibility was monitored in all groups to determine the cytotoxicity effect of particles on studied MC3T3-E1 preosteoblasts. AMPs showed significantly higher attachment rate than the HAs after 1 day and both AMPs and CMPs showed significantly higher proliferation rate when compared to HAs after 7 days. Gene expression level of osteoblastic markers ALP, COL I, OCN, OPN, RUNX2 were monitored and they were normalized to GAPDH housekeeping gene. Beta actin expression level was monitored as the second housekeeping gene to confirm the accuracy of results. In general, AMPs and CMPs showed higher expression level of osteoblastic genes after 7 days which can further confirm the stimulating role of Mg{sup +}2 and Ca{sup +2} ions in increasing the proliferation rate, differentiation, and mineralization of MC3T3-E1 preosteoblasts. - Highlights: • Role of Mg{sup 2

  9. Magnesium and calcium in exhaled breath condensate of children with asthma and gastroesophageal reflux disease.

    Science.gov (United States)

    Dodig, Slavica; Vlasić, Zeljka; Cepelak, Ivana; Zrinski Topić, Renata; Turkalj, Mirjana; Nogalo, Boro

    2009-01-01

    Magnesium and calcium physiologic functions are closely related. Magnesium is primarily an intracellular cation, the action of which also involves maintenance of cellular ionic balance, while influencing calcium homeostasis by blocking calcium channels. The aim of this study was to compare the concentrations of magnesium and calcium in exhaled breath condensate (EBC) of children with asthma and gastroesophageal reflux disease (GERD). EBC was collected from 66 children aged 7-14 years (23 children with acute asthma, 17 children with GERD, and 26 healthy children). Determination of magnesium and calcium concentrations was preceded by optimization and validation for low concentrations. No difference was recorded for either magnesium or calcium concentration between study groups. However, the magnesium to calcium ratio was statistically significantly lower in both GERD and asthma children as compared with control group. Study results showed the magnesium to calcium ratio to be a statistically significantly better indicator of certain pathologic changes than absolute concentration of either ion. Copyright 2009 Wiley-Liss, Inc.

  10. The co-effect of collagen and magnesium ions on calcium carbonate biomineralization

    Energy Technology Data Exchange (ETDEWEB)

    Jiao Yunfeng [Department of Materials Science and Engineering, Biomaterials Laboratory, Tsinghua University, Beijing 100084 (China); Feng Qingling [Department of Materials Science and Engineering, Biomaterials Laboratory, Tsinghua University, Beijing 100084 (China)]. E-mail: biomater@mail.tsinghua.edu.cn; Li Xiaoming [Department of Materials Science and Engineering, Biomaterials Laboratory, Tsinghua University, Beijing 100084 (China)

    2006-05-15

    The process of calcium carbonate biomineralization in the solution containing collagen and magnesium ions was studied in this paper. The results were characterized by using powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect rules were obtained by the cooperation of collagen and magnesium ions in different concentration. The experiment results showed that in the presence of both collagen and magnesium ions, aragonite and vaterite were precipitated at low Mg/Ca ion concentration ratio, while only aragonite with regular spherical morphology was precipitated at high Mg/Ca ion concentration ratio. It indicated that collagen has a promotional effect on magnesium ions in controlling the polymorph of calcium carbonate crystal. A much wider range of calcium carbonate morphologies was observed in the presence of both collagen and magnesium ions. The experiments suggested that collagen acts in combination with magnesium ions to inhibit calcite crystal growth, while favoring the formation of aragonite crystals.

  11. Crystallization Kinetics of Calcium-magnesium Aluminosilicate (CMAS) Glass

    Science.gov (United States)

    Wiesner, Valerie L.; Bansal, Narottam P.

    2015-01-01

    The crystallization kinetics of a calcium-magnesium aluminosilicate (CMAS) glass with composition relevant for aerospace applications, like air-breathing engines, were evaluated using differential thermal analysis (DTA) in powder and bulk forms. Activation energy and frequency factor values for crystallization of the glass were evaluated. X-ray diffraction (XRD) was used to investigate the onset of crystallization and the phases that developed after heat treating bulk glass at temperatures ranging from 690 to 960 deg for various times. Samples annealed at temperatures below 900 deg remained amorphous, while specimens heat treated at and above 900 deg exhibited crystallinity originating at the surface. The crystalline phases were identified as wollastonite (CaSiO3) and aluminum diopside (Ca(Mg,Al) (Si,Al)2O6). Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were employed to examine the microstructure and chemical compositions of crystalline phases formed after heat treatment.

  12. Multivariate regression models for the simultaneous quantitative analysis of calcium and magnesium carbonates and magnesium oxide through drifts data

    Directory of Open Access Journals (Sweden)

    Marder Luciano

    2006-01-01

    Full Text Available In the present work multivariate regression models were developed for the quantitative analysis of ternary systems using Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS to determine the concentration in weight of calcium carbonate, magnesium carbonate and magnesium oxide. Nineteen spectra of standard samples previously defined in ternary diagram by mixture design were prepared and mid-infrared diffuse reflectance spectra were recorded. The partial least squares (PLS regression method was applied to the model. The spectra set was preprocessed by either mean-centered and variance-scaled (model 2 or mean-centered only (model 1. The results based on the prediction performance of the external validation set expressed by RMSEP (root mean square error of prediction demonstrated that it is possible to develop good models to simultaneously determine calcium carbonate, magnesium carbonate and magnesium oxide content in powdered samples that can be used in the study of the thermal decomposition of dolomite rocks.

  13. Calcium and calcium magnesium carbonate specimens submitted as urinary tract stones.

    Science.gov (United States)

    Gault, M H; Chafe, L; Longerich, L; Mason, R A

    1993-02-01

    Of 8,129 specimens submitted as urinary stones from 6,095 patients, 67 from 15 patients were predominantly calcium carbonate or calcium magnesium carbonate (dolomite) by infrared analysis. Detailed study of 1 man and 4 women who submitted 3 or more such specimens showed that all were of aragonite calcium carbonate crystal form in 2 women and all calcite in the man. All 3 patients had a long history of nephrolithiasis preceding submission of calcium carbonate stones. There was frequent and often painful spontaneous passage of many small stones. Medullary sponge kidney was reported in 2 patients. Specimens submitted by the other 2 women included dolomite and quartz artifacts. Of the other 10 patients 4 had calcite and 1 had aragonite (possibly true stones). Five patients had artifacts with dolomite in 3 and mixed specimens in 2. True calcium carbonate kidney stones and calcium carbonate artifacts may be difficult to distinguish, and dolomite and quartz artifacts may require x-ray diffraction for clear-cut diagnosis.

  14. Estimation of calcium and magnesium in serum and urine by atomic absorption spectrophotometry

    Science.gov (United States)

    Thin, Christian G.; Thomson, Patricia A.

    1967-01-01

    A method has been described for the estimation of calcium and magnesium in serum and urine using atomic absorption spectrophotometry. The precision and accuracy of the techniques have been determined and were found to be acceptable. The range of values for calcium and magnesium in the sera of normal adults was found to be: serum calcium (corrected to a specific gravity of 1·026) 8·38-10·08 mg. per 100 ml.; serum magnesium 1·83-2·43 mg. per 100 ml. PMID:5602562

  15. Evaluation of the mechanical properties of acetic-cure silicone with the addition of magnesium silicate

    Directory of Open Access Journals (Sweden)

    Ronald Vargas Orellana

    2015-06-01

    Full Text Available Current study evaluates the mechanical properties (tensile and tear strength of an acetic-cure silicone with the addition of 10 or 20% vol. magnesium silicate. Magnesium silicate was added to the silicone at concentrations of 10 (MS-10 and 20% (MS-20 volume, followed by the analysis of tensile strength, maximal elongation during tensile and tear strength. Results were compared to control group of silicone without additives (CG. Mean rates were determined and compared by analysis of variance and Tukey’s test (p < 0.05. Control group had the greatest elongation when subjected to tensile strength (650%, whereas the MS-10 group statistically showed a better tensile strength (8.8 MPa when compared to CG (7.5 MPa and MS-20 (7.5 MPa groups. Both magnesium silicate groups exhibited statistically similar tear strength, whereas MS-20 group demonstrated statistically greater tear strength. The addition of 10% magnesium silicate increased tensile strength, but tear strength and elongation were similar to control. The addition of 20% magnesium silicate did not affect tensile but increased tear strength.

  16. Efficacy of Mixtures of Magnesium, Citrate and Phytate as Calcium Oxalate Crystallization Inhibitors in Urine.

    Science.gov (United States)

    Grases, Felix; Rodriguez, Adrian; Costa-Bauza, Antonia

    2015-09-01

    The main aim of the current study was to evaluate the effectiveness of mixtures of magnesium, citrate and phytate as calcium oxalate crystallization inhibitors. A turbidimetric assay in synthetic urine was performed to obtain induction times for calcium oxalate crystallization in the absence and presence of different mixtures of inhibitors. The morphology of calcium oxalate crystals in the absence or presence of inhibitors and mixtures of the inhibitors was evaluated in 2 crystallization experiments at low and high calcium oxalate supersaturation. The crystals formed were examined using scanning electron microscopy. Examination of crystallization induction times revealed clear inhibitory effects of magnesium, citrate and phytate on calcium oxalate crystallization, supporting usefulness in the treatment and prevention of calcium oxalate nephrolithiasis. Significant synergistic effects between magnesium and phytate were observed. Scanning electron microscopy images revealed that phytate is a powerful crystal growth inhibitor of calcium oxalate, totally preventing the formation of trihydrate and monohydrate. In addition to crystallization inhibition capacity, citrate and magnesium avoided calcium oxalate crystallization by decreasing its supersaturation. The synergistic effect between magnesium and phytate on calcium oxalate crystallization suggests that a combination of these 2 compounds may be highly useful as antilithiasis therapy. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  17. Final report on the safety assessment of aluminum silicate, calcium silicate, magnesium aluminum silicate, magnesium silicate, magnesium trisilicate, sodium magnesium silicate, zirconium silicate, attapulgite, bentonite, Fuller's earth, hectorite, kaolin, lithium magnesium silicate, lithium magnesium sodium silicate, montmorillonite, pyrophyllite, and zeolite.

    Science.gov (United States)

    Elmore, Amy R

    2003-01-01

    This report reviews the safety of Aluminum, Calcium, Lithium Magnesium, Lithium Magnesium Sodium, Magnesium Aluminum, Magnesium, Sodium Magnesium, and Zirconium Silicates, Magnesium Trisilicate, Attapulgite, Bentonite, Fuller's Earth, Hectorite, Kaolin, Montmorillonite, Pyrophyllite, and Zeolite as used in cosmetic formulations. The common aspect of all these claylike ingredients is that they contain silicon, oxygen, and one or more metals. Many silicates occur naturally and are mined; yet others are produced synthetically. Typical cosmetic uses of silicates include abrasive, opacifying agent, viscosity-increasing agent, anticaking agent, emulsion stabilizer, binder, and suspending agent. Clay silicates (silicates containing water in their structure) primarily function as adsorbents, opacifiers, and viscosity-increasing agents. Pyrophyllite is also used as a colorant. The International Agency for Research on Cancer has ruled Attapulgite fibers >5 microm as possibly carcinogenic to humans, but fibers Cosmetic Ingredient Review (CIR. The Cosmetic Ingredient Review (CIR) Expert Panel concluded that the extensive pulmonary damage in humans was the result of direct occupational inhalation of the dusts and noted that lesions seen in animals were affected by particle size, fiber length, and concentration. The Panel considers that most of the formulations are not respirable and of the preparations that are respirable, the concentration of the ingredient is very low. Even so, the Panel considered that any spray containing these solids should be formulated to minimize their inhalation. With this admonition to the cosmetics industry, the CIR Expert Panel concluded that these ingredients are safe as currently used in cosmetic formulations. The Panel did note that the cosmetic ingredient, Talc, is a hydrated magnesium silicate. Because it has a unique crystalline structure that differs from ingredients addressed in this safety assessment, Talc is not included in this report.

  18. Precipitation of Calcium, Magnesium, Strontium and Barium in Tissues of Four Acacia Species (Leguminosae: Mimosoideae)

    OpenAIRE

    Honghua He; Timothy M Bleby; ERIK J. VENEKLAAS; Hans Lambers; John Kuo

    2012-01-01

    Precipitation of calcium in plants is common. There are abundant studies on the uptake and content of magnesium, strontium and barium, which have similar chemical properties to calcium, in comparison with those of calcium in plants, but studies on co-precipitation of these elements with calcium in plants are rare. In this study, we compared morphologies, distributional patterns, and elemental compositions of crystals in tissues of four Acacia species grown in the field as well as in the glass...

  19. The influence of lithium on calcium and magnesium homeostasis in serum and tissues of rats.

    Science.gov (United States)

    Kiełczykowska, Małgorzata; Pasternak, Kazimierz; Musik, Irena

    2003-01-01

    Lithium is used in medicine. However, its administration can have negative side effects, disturb the water-electrolyte equilibrium and affect the level of essential elements. For these reasons the influence of oral lithium intoxication at the dose of 150 mg Li dm(-3) on magnesium and calcium levels in serum and tissues of rats was investigated. The concentration of Mg and Ca in serum increased throughout the experiment. The concentration of magnesium in tissues decreased after three weeks in liver, kidney, brain and femoral muscle. The trend of the changes of calcium tissue concentration was opposite to the one observed in the case of magnesium.

  20. Magnesium and calcium organophyllosilicates: synthesis and in vitro cytotoxicity study.

    Science.gov (United States)

    Han, Hyo-Kyung; Lee, Young-Chul; Lee, Moo-Yeol; Patil, Avinash J; Shin, Hyun-Jae

    2011-07-01

    Synthesis of multifunctional hybrid nanomaterials for biomedical applications has received great attention. Herein, we examine the potential toxicity of organophyllosilicates on cells from different organs such as A549 (lung epithelial cancer), HT-29 (colon epithelial cancer), MRC-5 (lung fibroblast) and CCD-986sk (skin fibroblast) cells. For this, aminopropyl functionalized magnesium phyllosilicate (AMP clay) and aminopropyl functionalized calcium phyllosilicate (ACP clay) were prepared using one-pot direct sol-gel method. Toxic effects of these organoclays on normal fibroblast and tumor cells were examined under varying concentrations and exposure times. MTT and LDH assays indicated that both organoclays had little cytotoxicity in all of the cells tested at concentrations as high as 500 μg/mL. Even at high concentration (1000 μg/mL), the toxicity of both organoclays on cell viability and membrane damage was not severe and appeared to be cell type specific. In addition, organoclays did not induce apoptosis at concentrations as high as 1000 μg/mL.

  1. A facile magnesium-containing calcium carbonate biomaterial as potential bone graft.

    Science.gov (United States)

    He, Fupo; Zhang, Jing; Tian, Xiumei; Wu, Shanghua; Chen, Xiaoming

    2015-12-01

    The calcium carbonate is the main composition of coral which has been widely used as bone graft in clinic. Herein, we readily prepared novel magnesium-containing calcium carbonate biomaterials (MCCs) under the low-temperature conditions based on the dissolution-recrystallization reaction between unstable amorphous calcium carbonate (ACC) and metastable vaterite-type calcium carbonate with water involved. The content of magnesium in MCCs was tailored by adjusting the proportion of ACC starting material that was prepared using magnesium as stabilizer. The phase composition of MCCs with various amounts of magnesium was composed of one, two or three kinds of calcium carbonates (calcite, aragonite, and/or magnesian calcite). The different MCCs differed in topography. The in vitro degradation of MCCs accelerated with increasing amount of introduced magnesium. The MCCs with a certain amount of magnesium not only acquired higher compressive strength, but also promoted in vitro cell proliferation and osteogenic differentiation. Taken together, the facile MCCs shed light on their potential as bone graft. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Synthesis Magnesium Hydroxide Nanoparticles and Cellulose Acetate- Mg(OH2-MWCNT Nanocomposite

    Directory of Open Access Journals (Sweden)

    M. Ghorbanali

    2015-04-01

    Full Text Available Mg(OH2 nanoparticles were synthesized by a rapid microwave reaction. The effect of sodium dodecyl sulfonate (SDS as anionic surfactant and cetyl tri-methyl ammonium bromide (CTAB as cationic surfactant on the morphology of magnesium hydroxide nanostructures was investigated. Multi wall carbon nano tubes was organo-modified for better dispersion in cellulose acetate matrix. The influence of Mg(OH2 nanoparticles and modified multi wall carbon nano tubes (MWCNT on the thermal stability of the cellulose acetate (CA matrix was studied using thermo-gravimetric analysis (TGA. Nanostructures were characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM and Fourier transform infrared (FT-IR spectroscopy. Thermal decomposition of the nanocomposites shift towards higher temperature in the presence of Mg(OH2 nanostructures. The enhancement of thermal stability of nanocomposites is due to the endothermic decomposition of Mg(OH2 and release of water which dilutes combustible gases.

  3. Enzymatic, urease-mediated mineralization of gellan gum hydrogel with calcium carbonate, magnesium-enriched calcium carbonate and magnesium carbonate for bone regeneration applications

    DEFF Research Database (Denmark)

    Douglas, Timothy; Lapa, Agata; Samal, Sangram K.

    Introduction: Mineralization of hydrogel biomaterials is considered desirable to improve their suitability as materials for bone regeneration[1],[2]. Hydrogels have been most commonly mineralized with calcium phosphate (CaP), but hydrogel-CaCO3 composites have received less attention. Magnesium (Mg......) has been added to CaP to stimulate cell adhesion and proliferation and bone regeneration in vivo, but its effect as a component of carbonate-based biomaterials remains uninvestigated. In this study, gellan gum (GG) hydrogels were mineralized enzymatically with (CaCO3), Mg-enriched CaCO3 and magnesium...... and subjected to physiochemical, mechanical and cell biological characterization. Results: FTIR, SEM, TGA and XRD analysis revealed that increasing magnesium concentration decreased mineral crystallinity. At low magnesium concentrations calcite was formed, while at higher concentrations magnesian calcite...

  4. In situ synthesis of magnesium-substituted biphasic calcium phosphate and in vitro biodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae-Wan; Lee, Hyeong-Shin; Kim, Dong-Hyun; Jin, Hyeong-Ho [School of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Hwang, Kyu-Hong [School of Nano and Advanced Materials, Gyeongsang National University, Jinju, Kyungnam 660-701 (Korea, Republic of); Lee, Jong Kook [Department of Advanced Materials Engineering, Chosun University, Gwangju 501-759 (Korea, Republic of); Park, Hong-Chae [School of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Yoon, Seog-Young, E-mail: syy3@pusan.ac.kr [School of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)

    2012-09-15

    Highlights: ► Mg–BCP were successfully prepared through in situ aqueous co-precipitation method. ► The amount of β-TCP phase was changed with the magnesium substitution level. ► The substitution of magnesium led to a decrease in the unit cell volume. ► Mg–BCP could be able to develop a new apatite phase on the surface faster than BCP. -- Abstract: In situ preparation of magnesium (Mg) substituted biphasic calcium phosphate (BCP) of hydroxyapatite (HAp)/β-tricalcium phosphate (β-TCP) were carried out through aqueous co-precipitation method. The concentrations of added magnesium were varied with the calcium in order to obtain constant (Ca + Mg)/P ratios of 1.602. X-ray diffraction (XRD) and Fourier transformed infrared (FTIR) spectroscopy were used to characterize the structure of synthesized magnesium substituted BCP powders. The results have shown that substitution of magnesium in the calcium deficient apatites revealed the formation of biphasic mixtures of different HAp/β-TCP ratios after heating at 1000 °C. The ratios of the formation of phase mixtures were dependent on the content of magnesium. After immersing in Hanks’ balanced salt solution (HBSS) for 1 week, 1 wt% magnesium substituted BCP powders were degraded and precipitation started to be formed with small granules consisting of number of flake-like crystal onto the surface of synthesized powders. On the other hand, in the case of pure BCP powders, the formation of new precipitates was detected after immersion in HBSS for 2 weeks. On the basis of these results, magnesium substituted BCP could be able to develop a new apatite phase on the surface in contact with physiological fluids faster than BCP does. In addition, the retention time to produce the new apatite phase in implantation operation for the BCP powder could be controlled by the amount of magnesium substitution.

  5. Bioactive Peptides Isolated from Casein Phosphopeptides Enhance Calcium and Magnesium Uptake in Caco-2 Cell Monolayers.

    Science.gov (United States)

    Cao, Yong; Miao, Jianyin; Liu, Guo; Luo, Zhen; Xia, Zumeng; Liu, Fei; Yao, Mingfei; Cao, Xiaoqiong; Sun, Shengwei; Lin, Yanyin; Lan, Yaqi; Xiao, Hang

    2017-03-22

    The ability of casein phosphopeptides (CPPs) to bind and transport minerals has been previously studied. However, the single bioactive peptides responsible for the effects of CPPs have not been identified. This study was to purify calcium-binding peptides from CPPs and to determine their effects on calcium and magnesium uptake by Caco-2 cell monolayers. Five monomer peptides designated P1 to P5 were isolated and the amino acid sequences were determined using LC-MS/MS. Compared with the CPP-free control, all five monomeric peptides exhibited significant enhancing effects on the uptake of calcium and magnesium (P magnesium were presented simultaneously with P5, magnesium was taken up with priority over calcium in the Caco-2 cell monolayers. For example, at 180 min, the amount of transferred magnesium and calcium was 78.4 ± 0.95 μg/well and 2.56 ± 0.64 μg/well, respectively, showing a more than 30-fold difference in the amount of transport caused by P5. These results provide novel insight into the mineral transport activity of phosphopeptides obtained from casein.

  6. Simultaneous determination of calcium and magnesium by derivative spectrophotometry in pharmaceutical products

    Science.gov (United States)

    Benamor, M.; Aguerssif, N.

    2008-02-01

    First- and second-derivative spectrophotometric methods for the simultaneous determination of calcium and magnesium in their mixtures are described. The methods are based on the colored complexes formed by calcium and magnesium with bromopyrogallol red in presence of Tween 80 as a surfactant. The zero-crossing method has been utilized to measure the first- and second-derivative value of the derivative spectrum. Calcium (0.8-4.8 μg ml -1) is determined in the presence of magnesium (0.5-3.5 μg ml -1) at the pH 10 and vice versa at zero-crossing wavelengths of 544.5 and 570 nm in the first-derivative procedure and 574 and 531 nm in the second-derivative procedure, respectively. The detection limits achieved were 0.0575 μg ml -1 of calcium and 0.03 μg ml -1 of magnesium. The relative standard deviations were in all instances less than 2%. The proposed method has been applied to the simultaneous determination of calcium and magnesium in different samples: commercial multivitamin, human serum and drinking water where excellent agreement between reported and obtained results was achieved.

  7. Simultaneous determination of calcium and magnesium by derivative spectrophotometry in pharmaceutical products.

    Science.gov (United States)

    Benamor, M; Aguerssif, N

    2008-02-01

    First- and second-derivative spectrophotometric methods for the simultaneous determination of calcium and magnesium in their mixtures are described. The methods are based on the colored complexes formed by calcium and magnesium with bromopyrogallol red in presence of Tween 80 as a surfactant. The zero-crossing method has been utilized to measure the first- and second-derivative value of the derivative spectrum. Calcium (0.8-4.8microgml(-1)) is determined in the presence of magnesium (0.5-3.5microgml(-1)) at the pH 10 and vice versa at zero-crossing wavelengths of 544.5 and 570nm in the first-derivative procedure and 574 and 531nm in the second-derivative procedure, respectively. The detection limits achieved were 0.0575microgml(-1) of calcium and 0.03microgml(-1) of magnesium. The relative standard deviations were in all instances less than 2%. The proposed method has been applied to the simultaneous determination of calcium and magnesium in different samples: commercial multivitamin, human serum and drinking water where excellent agreement between reported and obtained results was achieved.

  8. Involvement of T1R3 in calcium-magnesium taste.

    Science.gov (United States)

    Tordoff, Michael G; Shao, Hongguang; Alarcón, Laura K; Margolskee, Robert F; Mosinger, Bedrich; Bachmanov, Alexander A; Reed, Danielle R; McCaughey, Stuart

    2008-08-15

    Calcium and magnesium are essential for survival but it is unknown how animals detect and consume enough of these minerals to meet their needs. To investigate this, we exploited the PWK/PhJ (PWK) strain of mice, which, in contrast to the C57BL/6J (B6) and other inbred strains, displays strong preferences for calcium solutions. We found that the PWK strain also has strong preferences for MgCl2 and saccharin solutions but not representative salty, sour, bitter, or umami taste compounds. A genome scan of B6 x PWK F2 mice linked a component of the strain difference in calcium and magnesium preference to distal chromosome 4. The taste receptor gene, Tas1r3, was implicated by studies with 129.B6ByJ-Tas1r3 congenic and Tas1r3 knockout mice. Most notably, calcium and magnesium solutions that were avoided by wild-type B6 mice were preferred (relative to water) by B6 mice null for the Tas1r3 gene. Oral calcium elicited less electrophysiological activity in the chorda tympani nerve of Tas1r3 knockout than wild-type mice. Comparison of the sequence of Tas1r3 with calcium and saccharin preferences in inbred mouse strains found 1) an inverse correlation between calcium and saccharin preference scores across primarily domesticus strains, which was associated with an I60T substitution in T1R3, and 2) a V689A substitution in T1R3 that was unique to the PWK strain and thus may be responsible for its strong calcium and magnesium preference. Our results imply that, in addition to its established roles in the detection of sweet and umami compounds, T1R3 functions as a gustatory calcium-magnesium receptor.

  9. Effect of calcium, magnesium and sodium ions on in vitro nucleation of human gall bladder bile.

    OpenAIRE

    Neithercut, W D

    1989-01-01

    The effect of increasing the calcium, magnesium and sodium concentration in gall bladder bile samples from 21 patients with gall stones and nine controls on the in vitro rate of formation of cholesterol microcrystals and numbers of cholesterol microcrystals formed was examined. Addition of these cations to raise the mean maximum concentration of calcium ions to 19.8 mmol/l, of magnesium ions to 20 mmol/l and sodium ions to 998 mmol/l did not trigger nucleation in control bile samples or sampl...

  10. Antagonistic modulatory roles of magnesium and calcium on release of endothelium-derived relaxing factor and smooth muscle tone.

    Science.gov (United States)

    Gold, M E; Buga, G M; Wood, K S; Byrns, R E; Chaudhuri, G; Ignarro, L J

    1990-02-01

    The objective of this study was to elucidate the mechanisms associated with the reciprocal relation between magnesium and calcium on vascular smooth muscle tone in bovine pulmonary artery and vein. Rapid removal of magnesium from Krebs-bicarbonate medium used to bathe isolated rings of precontracted artery or vein caused transient endothelium- and calcium-dependent relaxation and cyclic GMP accumulation. Both responses were antagonized by oxyhemoglobin, methylene blue, or superoxide anion and were enhanced by superoxide dismutase. The transient relaxation was followed by sustained endothelium-independent contraction. Endothelium-denuded vascular rings contracted in response to extracellular magnesium depletion without alteration in cyclic GMP levels. The data suggest that vascular endothelium-derived nitric oxide is responsible for the calcium-dependent relaxation elicited by extracellular magnesium depletion. Indeed, in bioassay cascade studies, magnesium removal from the medium used to perfuse intact artery or vein enhanced the formation and/or release of an endothelium-derived relaxing factor by calcium-dependent mechanisms. In the absence of both extracellular magnesium and calcium, calcium readdition caused transient endothelium-dependent relaxation and cyclic GMP accumulation, and both responses were abolished by oxyhemoglobin or methylene blue. In the presence of magnesium, however, readdition of calcium to calcium-depleted medium caused only contractile responses. Addition of magnesium to calcium-containing medium consistently caused endothelium- and cyclic GMP-independent relaxation that was not altered by oxyhemoglobin or methylene blue. Thus, magnesium and calcium elicit reciprocal or mutually antagonistic effects at the levels of both endothelium-derived relaxing factor formation and/or release and smooth muscle contraction. This relation may be of physiological importance, and the possibility that a reduction in circulating magnesium levels could lead

  11. Calcium phosphate coatings on magnesium alloys for biomedical applications: a review.

    Science.gov (United States)

    Shadanbaz, Shaylin; Dias, George J

    2012-01-01

    Magnesium has been suggested as a revolutionary biodegradable metal for use as an orthopaedic material. As a biocompatible and degradable metal, it has several advantages over the permanent metallic materials currently in use, including eliminating the effects of stress shielding, improving biocompatibility concerns in vivo and improving degradation properties, removing the requirement of a second surgery for implant removal. The rapid degradation of magnesium, however, is a double-edged sword as it is necessary to control the corrosion rates of the materials to match the rates of bone healing. In response, calcium phosphate coatings have been suggested as a means to control these corrosion rates. The potential calcium phosphate phases and their coating techniques on substrates are numerous and can provide several different properties for different applications. The reactivity and low melting point of magnesium, however, require specific parameters for calcium phosphate coatings to be successful. Within this review, an overview of the different calcium phosphate phases, their properties and their behaviour in vitro and in vivo has been provided, followed by the current coating techniques used for calcium phosphates that may be or may have been adapted for magnesium substrates. Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. Calcium and magnesium in drinking water and risk of death from kidney cancer.

    Science.gov (United States)

    Chiu, Hui-Fen; Chang, Chih-Ching; Chen, Chih-Cheng; Yang, Chun-Yuh

    2011-01-01

    The possible association between the risk of kidney cancer development and the levels of calcium and magnesium in drinking water from municipal supplies was investigated in a matched cancer case-control study in Taiwan. All eligible kidney cancer deaths (1778 cases) of Taiwan residents from 1999 through 2008 were compared with deaths from other causes (1778 controls), and the levels of calcium and magnesium in drinking water of these residents were determined. Data on calcium and magnesium levels in drinking water throughout Taiwan were obtained from the Taiwan Water Supply Corporation (TWSC). The control group consisted of individuals who died from other causes, and the controls were pair-matched to the cancer cases by gender, year of birth, and year of death. The adjusted odd ratios for death attributed to kidney cancer for individuals with higher calcium levels in their drinking water, as compared to the lowest tertile, were 0.89 (95% CI = 0.72-1.11) and 0.78 (95% CI = 0.62-0.98), respectively. The adjusted odd ratios were not statistically significant for the relationship between magnesium levels in drinking water and kidney cancer development. The results of the present study demonstrate that there may be a significant protective effect of calcium intake from drinking water against the risk of death due to kidney cancer.

  13. Common variants in CLDN14 are associated with differential excretion of magnesium over calcium in urine.

    Science.gov (United States)

    Corre, Tanguy; Olinger, Eric; Harris, Sarah E; Traglia, Michela; Ulivi, Sheila; Lenarduzzi, Stefania; Belge, Hendrica; Youhanna, Sonia; Tokonami, Natsuko; Bonny, Olivier; Houillier, Pascal; Polasek, Ozren; Deary, Ian J; Starr, John M; Toniolo, Daniela; Gasparini, Paolo; Vollenweider, Peter; Hayward, Caroline; Bochud, Murielle; Devuyst, Olivier

    2017-01-01

    The nature and importance of genetic factors regulating the differential handling of Ca2+ and Mg2+ by the renal tubule in the general population are poorly defined. We conducted a genome-wide meta-analysis of urinary magnesium-to-calcium ratio to identify associated common genetic variants. We included 9320 adults of European descent from four genetic isolates and three urban cohorts. Urinary magnesium and calcium concentrations were measured centrally in spot urine, and each study conducted linear regression analysis of urinary magnesium-to-calcium ratio on ~2.5 million single-nucleotide polymorphisms (SNPs) using an additive model. We investigated, in mouse, the renal expression profile of the top candidate gene and its variation upon changes in dietary magnesium. The genome-wide analysis evidenced a top locus (rs172639, p = 1.7 × 10-12), encompassing CLDN14, the gene coding for claudin-14, that was genome-wide significant when using urinary magnesium-to-calcium ratio, but not either one taken separately. In mouse, claudin-14 is expressed in the distal nephron segments specifically handling magnesium, and its expression is regulated by chronic changes in dietary magnesium content. A genome-wide approach identified common variants in the CLDN14 gene exerting a robust influence on the differential excretion of Mg2+ over Ca2+ in urine. These data highlight the power of urinary electrolyte ratios to unravel genetic determinants of renal tubular function. Coupled with mouse experiments, these results support a major role for claudin-14, a gene associated with kidney stones, in the differential paracellular handling of divalent cations by the renal tubule.

  14. Acetate transiently inhibits myocardial contraction by increasing mitochondrial calcium uptake.

    Science.gov (United States)

    Schooley, James F; Namboodiri, Aryan M A; Cox, Rachel T; Bünger, Rolf; Flagg, Thomas P

    2014-12-09

    There is a close relationship between cardiovascular disease and cardiac energy metabolism, and we have previously demonstrated that palmitate inhibits myocyte contraction by increasing Kv channel activity and decreasing the action potential duration. Glucose and long chain fatty acids are the major fuel sources supporting cardiac function; however, cardiac myocytes can utilize a variety of substrates for energy generation, and previous studies demonstrate the acetate is rapidly taken up and oxidized by the heart. In this study, we tested the effects of acetate on contractile function of isolated mouse ventricular myocytes. Acute exposure of myocytes to 10 mM sodium acetate caused a marked, but transient, decrease in systolic sarcomere shortening (1.49 ± 0.20% vs. 5.58 ± 0.49% in control), accompanied by a significant increase in diastolic sarcomere length (1.81 ± 0.01 μm vs. 1.77 ± 0.01 μm in control), with a near linear dose response in the 1-10 mM range. Unlike palmitate, acetate caused no change in action potential duration; however, acetate markedly increased mitochondrial Ca(2+) uptake. Moreover, pretreatment of cells with the mitochondrial Ca(2+) uptake blocker, Ru-360 (10 μM), markedly suppressed the effect of acetate on contraction. Lehninger and others have previously demonstrated that the anions of weak aliphatic acids such as acetate stimulate Ca(2+) uptake in isolated mitochondria. Here we show that this effect of acetate appears to extend to isolated cardiac myocytes where it transiently modulates cell contraction.

  15. Acetate biodegradation by anaerobic microorganisms at high pH and high calcium concentration

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Takahiro, E-mail: t-yoshida@rwmc.or.j [Central Research Institute of Electric Power Industry (CRIEPI), Nuclear Technology Research Laboratory, 2-11-1, Iwado-kita, Komae, Tokyo 201-8511 (Japan)

    2011-02-15

    Acetate biodegradation at a high pH and a high calcium concentration was examined to clarify the effect of bacterial activity on the migration of organic {sup 14}C compounds in cementitious repositories. Tamagawa river sediment or Teganuma pond sediment was anaerobically cultured with 5 mM acetate and 10 mM nitrate at pH 9.5-12 at 30 {sup o}C. After 20 and 90 days, the acetate concentration of the culture medium was analyzed and found to have decreased below 5 mM at pH {<=} 11. On the other hand, it did not decrease when either sediment was incubated in the absence of nitrate. These results suggest that nitrate-reducing bacteria can biodegrade acetate under more alkaline conditions than the reported pH range in which nitrate-reducing bacteria can exhibit activity. Acetate biodegradation was also examined at a high calcium concentration. Sediments were anaerobically cultured at pH 9.5 with 5 mM acetate and 10 mM nitrate in solution, equilibrated with ordinary Portland cement hydrate, in which the Ca concentration was 14.6 mM. No decrease in acetate concentration after incubation of the sediments was observed, nor was it lower than in the absence of cementitious composition, suggesting that kinetics of acetate biodegradation by anaerobic microorganisms is lowered by a high Ca concentration. - Research highlights: {yields} Acetate biodegradation at a high pH and a high calcium concentration was examined to clarify the effect of bacterial activity on the migration of organic {sup 14}C compounds in cementitious repositories. {yields} Nitrate-reducing bacteria can biodegrade acetate at pH {<=} 11. {yields} Kinetics of acetate biodegradation by anaerobic microorganisms might be lowered by a high Ca concentration.

  16. Precipitation of calcium, magnesium, strontium and barium in tissues of four Acacia species (Leguminosae: Mimosoideae).

    Science.gov (United States)

    He, Honghua; Bleby, Timothy M; Veneklaas, Erik J; Lambers, Hans; Kuo, John

    2012-01-01

    Precipitation of calcium in plants is common. There are abundant studies on the uptake and content of magnesium, strontium and barium, which have similar chemical properties to calcium, in comparison with those of calcium in plants, but studies on co-precipitation of these elements with calcium in plants are rare. In this study, we compared morphologies, distributional patterns, and elemental compositions of crystals in tissues of four Acacia species grown in the field as well as in the glasshouse. A comparison was also made of field-grown plants and glasshouse-grown plants, and of phyllodes of different ages for each species. Crystals of various morphologies and distributional patterns were observed in the four Acacia species studied. Magnesium, strontium and barium were precipitated together with calcium, mainly in phyllodes of the four Acacia species, and sometimes in branchlets and primary roots. These elements were most likely precipitated in forms of oxalate and sulfate in various tissues, including epidermis, mesophyll, parenchyma, sclerenchyma (fibre cells), pith, pith ray and cortex. In most cases, precipitation of calcium, magnesium, strontium and barium was biologically induced, and elements precipitated differed between soil types, plant species, and tissues within an individual plant; the precipitation was also related to tissue age. Formation of crystals containing these elements might play a role in regulating and detoxifying these elements in plants, and protecting the plants against herbivory.

  17. Precipitation of Calcium, Magnesium, Strontium and Barium in Tissues of Four Acacia Species (Leguminosae: Mimosoideae)

    Science.gov (United States)

    He, Honghua; Bleby, Timothy M.; Veneklaas, Erik J.; Lambers, Hans; Kuo, John

    2012-01-01

    Precipitation of calcium in plants is common. There are abundant studies on the uptake and content of magnesium, strontium and barium, which have similar chemical properties to calcium, in comparison with those of calcium in plants, but studies on co-precipitation of these elements with calcium in plants are rare. In this study, we compared morphologies, distributional patterns, and elemental compositions of crystals in tissues of four Acacia species grown in the field as well as in the glasshouse. A comparison was also made of field-grown plants and glasshouse-grown plants, and of phyllodes of different ages for each species. Crystals of various morphologies and distributional patterns were observed in the four Acacia species studied. Magnesium, strontium and barium were precipitated together with calcium, mainly in phyllodes of the four Acacia species, and sometimes in branchlets and primary roots. These elements were most likely precipitated in forms of oxalate and sulfate in various tissues, including epidermis, mesophyll, parenchyma, sclerenchyma (fibre cells), pith, pith ray and cortex. In most cases, precipitation of calcium, magnesium, strontium and barium was biologically induced, and elements precipitated differed between soil types, plant species, and tissues within an individual plant; the precipitation was also related to tissue age. Formation of crystals containing these elements might play a role in regulating and detoxifying these elements in plants, and protecting the plants against herbivory. PMID:22848528

  18. Precipitation of calcium, magnesium, strontium and barium in tissues of four Acacia species (Leguminosae: Mimosoideae.

    Directory of Open Access Journals (Sweden)

    Honghua He

    Full Text Available Precipitation of calcium in plants is common. There are abundant studies on the uptake and content of magnesium, strontium and barium, which have similar chemical properties to calcium, in comparison with those of calcium in plants, but studies on co-precipitation of these elements with calcium in plants are rare. In this study, we compared morphologies, distributional patterns, and elemental compositions of crystals in tissues of four Acacia species grown in the field as well as in the glasshouse. A comparison was also made of field-grown plants and glasshouse-grown plants, and of phyllodes of different ages for each species. Crystals of various morphologies and distributional patterns were observed in the four Acacia species studied. Magnesium, strontium and barium were precipitated together with calcium, mainly in phyllodes of the four Acacia species, and sometimes in branchlets and primary roots. These elements were most likely precipitated in forms of oxalate and sulfate in various tissues, including epidermis, mesophyll, parenchyma, sclerenchyma (fibre cells, pith, pith ray and cortex. In most cases, precipitation of calcium, magnesium, strontium and barium was biologically induced, and elements precipitated differed between soil types, plant species, and tissues within an individual plant; the precipitation was also related to tissue age. Formation of crystals containing these elements might play a role in regulating and detoxifying these elements in plants, and protecting the plants against herbivory.

  19. Soil tillage, water erosion, and calcium, magnesium and organic carbon losses

    Directory of Open Access Journals (Sweden)

    Bertol Ildegardis

    2005-01-01

    Full Text Available Soil tillage influences water erosion, and consequently, losses of calcium, magnesium and organic carbon in surface runoff. Nutrients and organic carbon are transported by surface runoff in particulate form, adsorbed to soil colloids or soluble in water, depending on the soil tillage system. This study was carried out on an Inceptisol, representative of the Santa Catarina highlands, southern Brazil, between November 1999 and October 2001, under natural rainfall. The soil tillage treatments (no replications were: no-tillage (NT, minimum soil tillage with chiseling + disking (MT, and conventional soil tillage with plowing + two diskings (CT. The crop cycles sequence was soybean (Glycine max, oats (Avena sativa, beans (Phaseolus vulgaris and vetch (Vicia sativa. Conventional soil tillage treatment with plowing + two disking in the absence of crops (BS was also studied. Calcium and magnesium concentrations were determined in both water and sediments of the surface runoff, while organic carbon was measured only in sediments. Calcium and magnesium concentrations were greater in sediments than in surface runoff, while total losses of these elements were greater in surface runoff than in sediments. The greatest calcium and magnesium concentrations in surface runoff were obtained under CT, while in sediments the greatest concentration occurred under MT. Organic carbon concentration in sediments did not differ under the different soil tillage systems, and the greatest total loss was under CT system.

  20. Effects of dietary calcium, phosphorus and magnesium on intranephronic calculosis in rats.

    Science.gov (United States)

    Woodward, J C; Jee, W S

    1984-12-01

    The effects of varying dietary levels of calcium, phosphorus and magnesium on the incidence and severity of intranephronic calculosis were studied. Renal calculi were induced by feeding female rats the AIN-76TM semipurified diet for 4 weeks. During this time period, dietary levels of 350, 450 or 550 mg calcium per 100 g diet did not influence the occurrence of urolithiasis. Increasing dietary magnesium levels from 50 to 350 mg was beneficial in preventing the occurrence of calculi if the diet contained 400 mg or less phosphorus. The protective effects of dietary magnesium were counteracted when dietary phosphorus levels were increased from 400 mg to 550 or 700 mg. If the dietary content of phosphorus and magnesium permitted the formation of renal calculi, the severity of the condition was also influenced by the dietary level of calcium. Some animal groups fed semipurified diets did not have microscopic or radiographic evidence of renal calculi but were found to have significantly elevated renal calcium values. It was suggested that these animals might be in a precalculus-forming state.

  1. Serum magnesium, phosphate and calcium in Nigerian children with ...

    African Journals Online (AJOL)

    Background: Biochemical abnormalities have been associated with sickle cell disease. Studies on phosphorus and magnesium in sickle cell disease have been conflicting. There is paucity of information on the role of these ions in the pathogenesis and management of sickle cell disease. This study was set out to determine ...

  2. Effects of gadopentetate dimeglumine and gadodiamide on serum calcium, magnesium, and creatinine measurements.

    Science.gov (United States)

    Zhang, Hong Lei; Ersoy, Hale; Prince, Martin R

    2006-03-01

    To investigate the in vivo effects of gadodiamide (Gd-DTPA-BMA) and gadopentetate dimeglumine (Gd-DTPA) on the laboratory measurements of serum calcium, magnesium, and creatinine. Medical records from 1993 to 2004 were reviewed to identify inpatients for whom laboratory data were available regarding serum calcium, creatinine, and magnesium levels before and within one day after gadodiamide and gadopentetate dimeglumine enhanced MRI. Patients who underwent both gadolinium (Gd)-enhanced MRI and iodinated contrast-enhanced examinations on separate days within a six-month period were also identified to compare changes in serum creatinine. Serum creatinine did not increase in 2788 cases following gadopentetate dimeglumine and gadodiamide injection. By comparison, serum creatinine increased from 1.21 to 1.28 mg/dL following iodinated contrast, and there were 20 cases (2.6%) of contrast-induced nephrotoxicity (P Gadopentetate dimeglumine did not affect serum calcium or magnesium measurements. Following 1157 gadodiamide-enhanced examinations, measured serum calcium spuriously dropped from 8.65 to 8.33 mg/dL (P < 0.0001) and 34 patients had spurious critical hypocalcemia (<6 mg/dL). Of 60 patients with high-dose gadodiamide injection and renal insufficiency, 36.7% (N = 22) had spurious critical hypocalcemia immediately post MRI. In 216 patients with renal insufficiency, the mean serum magnesium level increased slightly from 1.69 to 1.77 mEq/L following gadodiamide injection (P < 0.0001). Gd-based contrast agents are safe for MRI and MR angiography (MRA), and do not induce nephrotoxicity. However, gadodiamide interferes with serum calcium and magnesium measurements-particularly at high doses and/or with renal insufficiency. (c) 2006 Wiley-Liss, Inc.

  3. Efficacy of Trichloro-Acetic Acid Peel Alone Versus Combined Topical Magnesium Ascorbyl Phosphate for Epidermal Melasma.

    Science.gov (United States)

    Murtaza, Fatima; Bangash, Abdur Rahim; Khushdil, Arshad; Noor, Sahibzada Mahmood

    2016-07-01

    To compare the efficacy in terms of reduction in melasma area and severity index (MASI) score by more than 10 of a combination of 20% trichloro-acetic acid peel plus 5% topical magnesium ascorbyl phosphate versus 20% trichloroacetic acid peel alone in the treatment of epidermal melasma. Randomized controlled trial. Department of Dermatology, Lady Reading Hospital (LRH), Peshawar, from May 2012 to May 2013. Patients aged 18 - 65 years, with Fitzpatrick skin type III-V were divided into two equal groups having 74 patients each. Detailed history was taken and Wood's lamp examination done to rule out mixed and dermal melasma. Melasma area and severity index (MASI) score was calculated for every patient. Priming was done for all patients with tretinoin cream applied once daily at night for 2 weeks, and to use a broad spectrum sun block cream before sun exposure. Patients in group Awere subjected to combined treatment, i.e. trichloro-acetic acid peel 20% (weekly) plus magnesium ascorbyl phosphate cream (applied once daily), while patients in group B were subjected to trichloro-acetic acid peel 20% (weekly) alone. Treatment was continued for 6 weeks. After completion of treatment, MASI score was recalculated. Proportion of patients with significant MASI score reduction was compared using chi-square test with significance at p peel and topical magnesium ascorbyl phosphate cream was significantly more effective than trichloro-acetic acid peel alone in treatment of melasma.

  4. Predicting effects on oxaliplatin clearance: in vitro, kinetic and clinical studies of calcium- and magnesium-mediated oxaliplatin degradation.

    Science.gov (United States)

    Han, Catherine H; Khwaounjoo, Prashannata; Hill, Andrew G; Miskelly, Gordon M; McKeage, Mark J

    2017-06-22

    This study evaluated the impact of calcium and magnesium on the in vitro degradation and in vivo clearance of oxaliplatin. Intact oxaliplatin and Pt(DACH)Cl2 were measured in incubation solutions by HPLC-UV. A clinical study determined changes in plasma concentrations of calcium and magnesium in cancer patients and their impact on oxaliplatin clearance. Kinetic analyses modelled oxaliplatin degradation reactions in vitro and contributions to oxaliplatin clearance in vivo. Calcium and magnesium accelerated oxaliplatin degradation to Pt(DACH)Cl2 in chloride-containing solutions in vitro. Kinetic models based on calcium and magnesium binding to a monochloro-monooxalato ring-opened anionic oxaliplatin intermediate fitted the in vitro degradation time-course data. In cancer patients, calcium and magnesium plasma concentrations varied and were increased by giving calcium gluconate and magnesium sulfate infusions, but did not alter or correlate with oxaliplatin clearance. The intrinsic in vitro clearance of oxaliplatin attributed to chloride-, calcium- and magnesium-mediated degradation predicted contributions of vitro degradation of oxaliplatin by binding to a monochloro-monooxalato ring-opened anionic intermediate. Kinetic analysis of in vitro oxaliplatin stability data can be used for in vitro prediction of potential effects on oxaliplatin clearance in vivo.

  5. [Ionic calcium and magnesium from pharmaceutical product BEROCCA effects on neuromuscular excitability].

    Science.gov (United States)

    Stratone, Ana; Stratone, Carmen; Chiruţă, Roxana; Zaharia, D; Căruntu, Lidia; Diaconu, Mariana; Stefancu, Oana; Topoliceanu, Fl

    2005-01-01

    The important physiological role of calcium and magnesium ions is all over recognised, about a lot of enzymatic reactions. Magnesium deficit produce neuromuscular hyper-reactivity, psychic reactions, functional hypoparathyroidism, increase of K+ channels membranes permeability, while hypermagnesemia decrease Ach release from neuromuscular synapsis, with post-synaptic excitability decreasing. Using BEROCCA (Hoffman la Roche) 1 cp/day, 30 days at the teenagers with behaviour troubles and at a goup of pregnant women (trimester I-III) with paresthesia, irritability, sleeplessness, we observed an improve of clinical signs, increasing plasma Ca2+ and Mg2+. EEG and EMG prove the beneficial effects of pharmaceutical product BEROCCA.

  6. Serum calcium and magnesium level in dairy cows at calving

    Directory of Open Access Journals (Sweden)

    A.M. Pulimeno

    2011-03-01

    Full Text Available Milk fever and hypocalcaemia are post-partum metabolic diseases affecting about 6% of dairy cows and are due to a fail of the homeostatic metabolism regulating the calcium blood level around 9 and 10mg/100mL. The calcium drainage to the mammary gland along with the reduced capacity of the animal to mobilize calcium from bone reserve lead to a drop of the calcium blood level under 5-6mg/100mL with paresis like clinical symptoms known as milk fever. The incidence of the clinical milk fever is low, however the occurrence of mild hypocalcaemia (subclinical could be as high as 15- 20% within few days after calving, particularly in multiparous cows. The hypocalcaemia status as for the reduced bone calcium mobilization and intestinal absorption leads to reduced feed intake and make it a good start for ketosis, retained placenta, displaced abomasums and mastitis problems (Beede, 1991. The acid-base balance of the cow in the late pregnancy is determinant for hypocalcaemia............

  7. Synergistic flame retardant effects between sepiolite and magnesium hydroxide in ethylene-vinyl acetate (EVA matrix

    Directory of Open Access Journals (Sweden)

    2010-04-01

    Full Text Available Some customers are reluctant to change, because the halogen-free solutions may have higher cost. This is one of the reasons that the synergistic effect is always the subject for researchers to pursue. The synergy between sepiolite and magnesium hydroxide (MH in halogen-free flame retardant ethylene-vinyl acetate (EVA copolymer was investigated in the paper through some common facilities, such as limiting oxygen index (LOI, UL-94 test, thermogravimetric analysis (TGA, differential thermal analysis (DTA and cone calorimeter test (CCT. In the wake of the positive results from the LOI and UL-94 tests, the CCT data indicated not only the reduction of heat release rate (HRR and mass loss rates (MLR, but also prolonged ignition time (TTI and depressed smoke release (SR were observed during combustion. Simultaneously, the tensile strength and Young’s modulus of the system were also much better improved with the increase of sepiolite added due to the hydrogen bonds between silanol groups attached to the sepiolite molecules and the ester groups of EVA. The synergistic mechanism has been discussed in the paper in terms of the barrier mechanism in the condensed phase.

  8. Calcium and magnesium levels in isolated mitochondria from human cardiac biopsies.

    Science.gov (United States)

    Saetersdal, T; Engedal, H; Røli, J; Myklebust, R

    1980-01-01

    A non-enzymatic method is presented for isolating mitochondria from small-sized human cardiac samples, including ventricular needle biopsies of 15-25 mg of wet weight. Electron microscopy demonstrates that these fractions are rich in structurally well preserved mitochondria. Calcium and magnesium levels of fractions are determined by atomic absorption flame spectroscopy. Comparative analyses are made in similar fractions of the mouse ventricle. Calcium concentrations of mitocondria isolated in the presence of ruthenium red do not differ significantly between the human auricle and ventricle, averaging 61 nmol Ca/mg protein and 68 nmol Ca/mg protein, respectively. Mitochondrial calcium level is lower in the mouse ventricular fractions, averaging 7 nmol Ca/mg protein. Mitochondrial magnesium amounts to slightly less than 60% of the calcium levels in the human heart, while it exceeds the calcium level by more than 100 per cent in the mouse heart. There is no significant difference of mitochondrial calcium between normal auricles, and, auricles of patients with increased right atrial mean pressure and/or volume overload.

  9. Magnesium: origin and role in calcium-treated inclusions

    CSIR Research Space (South Africa)

    Pistorius, PC

    2009-08-01

    Full Text Available Steel was sampled after calcium treatment at an industrial steel plant, and the inclusions identified by energy-dispersive X-ray microanalysis (EDX) on polished sections of the samples analysing the samples in a scanning electron microscope...

  10. [Effect of octadecyl amine (ODA) on the complex titration of magnesium and calcium ions studied with UV-visible spectrophotometry].

    Science.gov (United States)

    Qing, Bin-Ju; Liu, Hai-Ning; Ye, Xiu-Shen; Li, Quan; Guo, Min; Liu, Teng-Yun; Wu, Zhi-Jian

    2009-10-01

    The effect of flotation agent octadecyl amine (ODA) on the complex titration of both magnesium and calcium ions was studied with two groups of comparative experiments: (1) Before titration, the suspension was not filtered. In this case, ODA had a great effect on the complex titration of both magnesium and calcium ions. The titration end-point of magnesium ions was difficult to be determined. Although the titration end-point of calcium ions could be determined, there was an obvious experimental error compared with the blank solution without ODA. These results were confirmed by the UV-Visible spectrum analyses of the related solutions. (2) Before titration, the suspension was filtered. In this case, the influence of ODA on the complex titration of both magnesium and calcium ions could be removed. UV-Visible spectrum studies showed that, in this case, both the spectra and time scanning curves of the tested solutions were similar to those of the blank solutions.

  11. Limited effect of low frequency magnetic fields on the concentrations of calcium, magnesium and fluoride in saliva.

    Science.gov (United States)

    Skomro, Piotr; Opalko, Krystyna; Bohdziewicz, Olga; Nocen, Iwona; Janiszewska-Olszowska, Joanna

    2009-06-01

    To assess the influence of low frequency magnetic fields on the contents of calcium, magnesium and fluoride in saliva. Sixty two patients were subjected to magnetic stimulation with low frequency magnetic fields of mean induction 3 microT at the first intervention and 4 microT at the following fourteen ones. Saliva was sampled before magnetic stimulation and after the 5th, 10th and 15th interventions. The contents of calcium and magnesium ions were measured by means of atomic absorption spectrometry. The content of fluoride was determined using an ion-selective electrode. No statistically significant differences were found between the calcium concentrations before magnetic stimulation and after 5, 10 and 15 interventions. Statistically significant differences in the magnesium concentrations were observed only between 10th and 15th interventions. No statistically significant differences in fluoride concentrations were found. Low frequency magnetic fields have no or weak influences on the content of calcium, magnesium and fluoride in saliva.

  12. [Comparative study of the urinary excretion of boron, calcium, magnesium and phosphorus in postmenopausal women with and without osteoporosis].

    Science.gov (United States)

    José Ramón, Vielma; Mora Mora, Marylú; Marino Alarcón, Oscar; Hernández, Gladys; Josefina Linares, Ledy; Urdaneta Romero, Haideé; Arévalo González, Evelia

    2012-03-01

    In order to compare the possible relationship between urinary concentrations of boron, calcium, magnesium and phosphorus in serum and urine of postmenopausal women with and without osteoporosis, we selected 45 postmenopausal women over 47 years of age, divided into two groups: group I clinically healthy postmenopausal women and group II postmenopausal women with osteoporosis, without chronic kidney and hepatic diseases or diabetes mellitus. We determined the boron (B), phosphorus (P), total calcium (Ca) and total magnesium (Mg) in the urine of two hours, by atomic emission spectroscopy with induction-coupled plasma (ICPA-ES). Total calcium and total magnesium in serum were determined by atomic flame absorption spectroscopy (FAAS) and inorganic phosphorus in serum, and creatinine in serum and urine, by molecular absorption spectrometry. The preliminary results suggest the existence of a significant difference (p calcium/ creatinine, magnesium/creatinine and phosphorus/creatinine indexes in the urine of postmenopausal women with osteoporosis.

  13. Stress-Relaxation Behavior of Magnesium-3Gadolinium-2Calcium-Based Alloys at Elevated Temperatures

    Science.gov (United States)

    Mo, Ning; Tan, Qiyang; Jiang, Bin; Pan, Fusheng; Zhang, Ming-Xing

    2017-11-01

    Based on previously published work on binary Mg alloys by Abaspour et al. and on the magnesium (Mg)-6gadolinium (Gd)-2zinc (Zn)-0.6zirconium (Zr) (wt pct) alloy reported by Nie et al., a number of new lower-cost Mg-3Gd-2calcium (Ca) (wt pct)-based creep-resistant magnesium alloys were developed by replacing part of the Gd with Ca. After solution treatment at 793 K (520 °C), the Ca-containing alloys exhibited an increased strength and a reduced stress relaxation at 453 K (180 °C) compared with the Mg-6Gd-2Zn-0.6Zr (wt pct) alloy. This work indicates that the replacement of Gd with Ca is a promising approach to develop lower-cost Mg alloys with an improved creep resistance. The results support the hypothesis that the short-range order of solutes governs the creep behavior of magnesium alloys.

  14. Effect of Diuretics on Renal Tubular Transport of Calcium and Magnesium

    DEFF Research Database (Denmark)

    Alexander, R Todd; Dimke, Henrik

    2017-01-01

    Calcium (Ca2+) and Magnesium (Mg2+) reabsorption along the renal tubule is dependent on distinct trans- and paracellular pathways. Our understanding of the molecular machinery involved is increasing. Ca2+ and Mg2+ reclamation in kidney is dependent on a diverse array of proteins, which are import......Calcium (Ca2+) and Magnesium (Mg2+) reabsorption along the renal tubule is dependent on distinct trans- and paracellular pathways. Our understanding of the molecular machinery involved is increasing. Ca2+ and Mg2+ reclamation in kidney is dependent on a diverse array of proteins, which...... are important for both forming divalent cation permeable pores and channels, but also for generating the necessary driving forces for Ca2+ and Mg2+ transport. Alterations in these molecular constituents lead to profound effects on tubular Ca2+ and Mg2+ handling. Diuretics are used to treat a large range...

  15. Hypolipidemic Activity of a Natural Mineral Water Rich in Calcium, Magnesium, and Bicarbonate in Hyperlipidemic Adults

    Directory of Open Access Journals (Sweden)

    Naser Aslanabadi

    2014-05-01

    Full Text Available Purpose: This study compared the effects of a mineral water rich in calcium, magnesium, bicarbonate, and sulfate and a marketed mineral water with a composition similar to that of urban water on the lipid profile of dyslipidemic adults. Methods: In a randomized controlled trial, 32 adults received one liter of "rich mineral water" daily for one month, and 37 adults drank the same amount of normal mineral water for the same period. Changes in lipid profiles were compared separately in each studied group at the end of one month. Results: Results showed that mean cholesterol and low density lipoprotein LDL levels were significantly decreased in both studied groups after one month of drinking mineral water (P0.05. Conclusion: A one-month intake of mineral water rich in calcium, magnesium bicarbonate, and sulfate decreased cholesterol and LDL levels but not TG or HDL levels in dyslipidemic adults.

  16. Magnesium

    Science.gov (United States)

    ... in the body, including regulating muscle and nerve function, blood sugar levels, and blood pressure and making protein , bone, and DNA . How much magnesium do I need? The amount of magnesium you ...

  17. Plasma Calcium, Inorganic Phosphate and Magnesium During Hypocalcaemia Induced by a Standardized EDTA Infusion in Cows

    Directory of Open Access Journals (Sweden)

    Enemark JMD

    2001-06-01

    Full Text Available The intravenous Na2EDTA infusion technique allows effective specific chelation of circulating Ca2+ leading to a progressive hypocalcaemia. Methods previously used were not described in detail and results obtained by monitoring total and free ionic calcium were not comparable due to differences in sampling and analysis. This paper describes a standardized EDTA infusion technique that allowed comparison of the response of calcium, phosphorus and magnesium between 2 groups of experimental cows. The concentration of the Na2EDTA solution was 0.134 mol/l and the flow rate was standardized at 1.2 ml/kg per hour. Involuntary recumbency occurred when ionised calcium dropped to 0.39 – 0.52 mmol/l due to chelation. An initial fast drop of ionized calcium was observed during the first 20 min of infusion followed by a fluctuation leading to a further drop until recumbency. Pre-infusion [Ca2+] between tests does not correlate with the amount of EDTA required to induce involuntary recumbence. Total calcium concentration measured by atomic absorption remained almost constant during the first 100 min of infusion but declined gradually when the infusion was prolonged. The concentration of inorganic phosphate declined gradually in a fluctuating manner until recumbency. Magnesium concentration remained constant during infusion. Such electrolyte responses during infusion were comparable to those in spontaneous milk fever. The standardized infusion technique might be useful in future experimental studies.

  18. A study of serum magnesium and serum calcium in major depressive disorder

    Directory of Open Access Journals (Sweden)

    Niladri Deb

    2016-01-01

    Full Text Available Background: Depression is arguably the epidemic of our time. In one of the reports of the World Health Organization, it was projected that depression and heart disease will be the most common diseases on Earth by 2020. The paper attempts to determine the relationship between the pathophysiology of major depressive disorder (MDD and serum magnesium and serum calcium levels. Methodology: The study is based on a sample of 60 subjects–30 healthy normal individuals and 30 indoor and outdoor patients of the Department of Psychiatry of Gauhati Medical College and Hospital, Guwahati, who were identified by psychiatrist as having MDD as per the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV criteria. Estimation of the parameters of the study was done by using spectrophotometre (Spectra scan UV 2600. The result values of both the groups were compared by using independent ‘t’ test. Further, the correlation between serum magnesium and serum calcium among individuals of control as well as case groups were carried out by using Pearson’s correlation test. Results: Analysis of data reveals the mean value of serum magnesium among subjects of control group was higher than that of the subjects of the case (before treatment group while in case of serum calcium, it was the vice versa. Moreover, in both the cases, the differences in mean values were found to be statistically significant. Conclusion: The present study shows that alterations in the concentrations of magnesium and calcium may play a role in depressive illnesses and thus, may have a possible role in causing various mood disorders like MDD.

  19. Determination of calcium and magnesium water hardness with rapid test, titration and spectrometry

    OpenAIRE

    Drnovšek, Urška

    2016-01-01

    Water is a substance without colour, smell or taste and without which life on earth would be impossible. Drinkable water and rivers contain different substances; quantity and sort of the latter differs regarding the region of the source of water, chemical structure of the ground on which and through which it flows. Water hardness is caused mostly by hydrogen carbonates, calcium and magnesium ions. The greater the quantity of those dissolved in natural water from the soil and rocks, the harder...

  20. Phase composition, mechanical performance and in vitro biocompatibility of hydraulic setting calcium magnesium phosphate cement.

    Science.gov (United States)

    Klammert, Uwe; Reuther, Tobias; Blank, Melanie; Reske, Isabelle; Barralet, Jake E; Grover, Liam M; Kübler, Alexander C; Gbureck, Uwe

    2010-04-01

    Brushite (CaHPO(4) x 2H(2)O)-forming calcium phosphate cements are of great interest as bone replacement materials because they are resorbable in physiological conditions. However, their short setting times and low mechanical strengths limit broad clinical application. In this study, we showed that a significant improvement of these properties of brushite cement could be achieved by the use of magnesium-substituted beta-tricalcium phosphate with the general formula Mg(x)Ca((3-x))((PO(4))(2) with 0 forming newberyite (MgHPO(4) x 3H(2)O) as a second setting product. The biocompatibility of the material was investigated in vitro using the osteoblast-like cell line MC3T3-E1. A considerable increase of cell proliferation and expression of alkaline phosphatase, indicating an osteoblastic differentiation, could be noticed. Scanning electron microscopy analysis revealed an obvious cell growth on the surface of the scaffolds. Analysis of the culture medium showed minor alterations of pH value within the physiological range. The concentrations of free calcium, magnesium and phosphate ions were altered markedly due to the chemical solubility of the scaffolds. We conclude that the calcium magnesium phosphate (newberyite) cements have a promising potential for their use as bone replacement material since they provide a suitable biocompatibility, an extended workability and improved mechanical performance compared with brushite cements. Copyright 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  1. Quality medicines in maternal health: results of oxytocin, misoprostol, magnesium sulfate and calcium gluconate quality audits.

    Science.gov (United States)

    Anyakora, Chimezie; Oni, Yetunde; Ezedinachi, Uchenna; Adekoya, Adebola; Ali, Ibrahim; Nwachukwu, Charles; Esimone, Charles; Abiola, Victor; Nwokike, Jude

    2018-01-30

    The high level of maternal mortality and morbidity as a result of complications due to childbirth is unacceptable. The impact of quality medicines in the management of these complications cannot be overemphasized. Most of those medicines are sensitive to environmental conditions and must be handled properly. In this study, the quality of oxytocin injection, misoprostol tablets, magnesium sulfate, and calcium gluconate injections was assessed across the six geopolitical zones of Nigeria. Simple, stratified random sampling of health facilities in each of the political zones of Nigeria. Analysis for identification and content of active pharmaceutical ingredient was performed using high-performance liquid chromatography procedures of 159 samples of oxytocin injection and 166 samples of misoprostol tablets. Titrimetric methods were used to analyze 164 samples of magnesium sulfate and 148 samples of calcium gluconate injection. Other tests included sterility, pH measurement, and fill volume. Samples of these commodities were procured mainly from wholesale and retail pharmacies, where these were readily available, while the federal medical centers reported low availability. Approximately, 74.2% of oxytocin injection samples failed the assay test, with the northeast and southeast zones registering the highest failure rates. Misoprostol tablets recorded a percentage failure of 33.7%. Magnesium sulfate and Calcium gluconate injection samples recorded a failure rate of 6.8% and 2.4%, respectively. The prevalence of particularly of oxytocin and misoprostol commodities was of substandard quality. Strengthening the supply chain of these important medicines is paramount to ensuring their effectiveness in reducing maternal deaths in Nigeria.

  2. Productivity and nutritive value of bluestem grass fertilized with calcium and magnesium silicate

    Directory of Open Access Journals (Sweden)

    Cinthya Souza Santana

    2016-01-01

    Full Text Available This study evaluated the effect of application of calcium and magnesium silicate on the productivity, chemical composition and in situ ruminal degradation of bluestem grass (Andropogon gayanus Kunth, cv. Baeti; Embrapa 23 during the rainy and dry seasons. The design consisted of completely randomized blocks in a 6x2 factorial scheme (six silicate doses and two cutting seasons, arranged in plots subdivided over time. The plots were the calcium and magnesium silicate doses (0, 200, 400, 600, 800 and 1,000 kg/ha and the subplots were the two cutting seasons (rainy and dry period, with five repetitions (blocks. The calcium and magnesium silicate doses exerted no significant effect on green or dry matter production, chemical forage composition or degradability parameters. On the other hand, there was an effect of cutting period on forage production and chemical composition. The highest production of green and dry matter was observed during the rainy period, while acid detergent fiber content was higher during the dry season. The treatments did not exert any significant effect on the parameters of degradability that would alter the nutritive value of bluestem grass.

  3. The simultaneous removal of calcium, magnesium and chloride ions from industrial wastewater using magnesium-aluminum oxide.

    Science.gov (United States)

    Hamidi, Roya; Kahforoushan, Davood; Fatehifar, Esmaeil

    2013-01-01

    In this article, a method for simultaneous removal of calcium, magnesium and chloride by using Mg0.80Al0.20O1.10 as a Magnesium-Aluminum oxide (Mg‒Al oxide) was investigated. Mg‒Al oxide obtained by thermal decomposition of the Mg-Al layered double hydroxide (Mg-Al LDH). The synthesized Mg‒Al oxide were characterized with respect to nitrogen physicosorption, X-ray diffraction (XRD) and field emission scan electron microscopy (FESEM) morphology. Due to high anion-exchange capacity of Mg‒Al oxide, it was employed in simultaneously removal of Cl(-), Mg(+2) and Ca(+2) from distiller waste of a sodium carbonate production factory. For this purpose, experiments were designed to evaluate the effects of quantity of Mg‒Al oxide, temperature and time on the removal process. The removal of Cl(-), Mg(+2) and Ca(+2) from wastewater was found 93.9%, 93.74% and 93.25% at 60°C after 0.5 h, respectively. Results showed that the removal of Cl(-), Mg(+2) and Ca(+2) by Mg‒Al oxide increased with increasing temperature, time and Mg‒Al oxide quantity.

  4. Assay of calcium borogluconate veterinary medicines for calcium gluconate, boric acid, phosphorus, and magnesium by using inductively coupled plasma emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lyons, D.J.; Spann, K.P.

    1985-03-01

    An inductively coupled plasma spectrometric method is described for the determination of 4 elements (Ca, B, P, and Mg) in calcium borogluconate veterinary medicines. Samples are diluted, acidified, and sprayed directly into the plasma. Reproducibility relative confidence intervals for a single sample assay are +/- 1.4% (calcium), +/- 1.8% (boron), +/- 2.6% (phosphorus), and +/- 1.4% (magnesium). The total element concentrations for each of 4 elements compared favorably with concentrations determined by alternative methods. Formulation estimates of levels of calcium gluconate, boric acid, phosphorus, and magnesium salts can be made from the analytical data.

  5. CO2 capture performance of Ca-Mg acetates at realistic Calcium Looping conditions

    OpenAIRE

    Miranda-Pizarro, Juan; Perejón, Antonio; Valverde, J.M.; Pérez-Maqueda, Luis A.; Sánchez-Jiménez, P.E.

    2017-01-01

    The Calcium Looping (CaL) process, based on the cyclic carbonation/calcination of CaO, has emerged in the last years as a potentially low cost technique for CO2 capture at reduced energy penalty. In the present work, natural limestone and dolomite have been pretreated with diluted acetic acid to obtain Ca and Ca-Mg mixed acetates, whose CO2 capture performance has been tested at CaL conditions that necessarily imply sorbent regeneration under high CO2 partial pressure. The CaL multicycle capt...

  6. The effect of short chain fatty acid administration on hepatic glucose, phosphate, magnesium and calcium metabolism.

    Science.gov (United States)

    Veech, R L; Gitomer, W L; King, M T; Balaban, R S; Costa, J L; Eanes, E D

    1986-01-01

    Intra peritoneal administration of the short chain fatty acids, acetate, propionate and butyrate, in amounts calculated to reach 20 mM in total body water were given to fed and 48 hour starved male Wistar rats. One half hour after administration, the livers were freeze-clamped and the hepatic contents of various intermediary metabolites were measured. The liver content of total glycolytic intermediates was elevated by short chain fatty acids. In fed animals, the portion of glycolysis from fructose 1,6-bisphosphate (FBP) to PEP was elevated 2 to 4 fold. In 48 hour starved animals, where gluconeogenesis is active, the portion of the gluconeogenetic pathway from FBP to glucose was elevated 1.5 to 3.5 fold with the exception of the butyrate treated animals where blood glucose was not elevated. The metabolites of the hexose-monophosphate pathway that were measured, namely 6-phosphogluconate, ribulose 5-phosphate and xylose 5-phosphate were increased in both fed and starved animals. The free cytoplasmic [NAD+]/[NADH], [NADP+]/[NADPH], and [epsilon ATP]/[epsilon ADP] X [epsilon Pi] ratios were all decreased in both fed and starved animals after short chain fatty acid administration. The liver content of calcium increased 1.2 to 2 fold in fed animals and 2 to 3 fold in starved animals while total liver magnesium was either unchanged or increased only 1.2 times. The liver pyrophosphate (PPi) content increased a minimum of 10 fold in fed animals and over 100 fold in starved animals. In all cases no PPi could be detected in vivo by 31P NMR even though in the starved rats the PPi levels approached those of ATP. The liver content of inorganic Pi increased 1.3 to 1.5 fold in fed animals and 1.5 to 2 fold in starved animals. The total "rapidly metabolizing" Pi pool, that includes adenine and guanine nucleotides, glycolytic and shunt intermediates, Pi and PPi increased 1.3 times in fed animals (from 13.8 mumole/g fresh weight) and 1.5 to 1.7 fold in starved animals (from 15

  7. Ion Implantation of Calcium and Zinc in Magnesium for Biodegradable Implant Applications

    Directory of Open Access Journals (Sweden)

    Sahadev Somasundaram

    2018-01-01

    Full Text Available In this study, magnesium was implanted with calcium-ion and zinc-ion at fluences of 1015, 1016, and 1017 ion·cm−2, and its in vitro degradation behaviour was evaluated using electrochemical techniques in simulated body fluid (SBF. Rutherford backscattering spectrometry (RBS revealed that the implanted ions formed layers within the passive magnesium-oxide/hydroxide layers. Electrochemical impedance spectroscopy (EIS results demonstrated that calcium-ion implantation at a fluence of 1015 ions·cm−2 increased the polarisation resistance by 24%, but higher fluences showed no appreciable improvement. In the case of zinc-ion implantation, increase in the fluence decreased the polarisation resistance. A fluence of 1017 ion·cm−2 decreased the polarisation resistance by 65%, and fluences of 1015 and 1016 showed only marginal effect. Similarly, potentiodynamic polarisation results also suggested that low fluence of calcium-ion decreased the degradation rate by 38% and high fluence of zinc-ion increased the degradation rate by 61%. All the post-polarized ion-implanted samples and the bare metal revealed phosphate and carbonate formation. However, the improved degradative behaviour in calcium-ion implanted samples can be due to a relatively better passivation, whereas the reduction in degradation resistance in zinc-ion implanted samples can be attributed to the micro-galvanic effect.

  8. Qualitative discussion of prenucleation cluster role in crystallization of calcium carbonate under high concentration of magnesium based on experimental phenomena

    Science.gov (United States)

    Zhang, Jie; Sun, Yuzhu; Yu, Jianguo

    2017-11-01

    Crystallization of calcium carbonate under high concentration of magnesium was studied. Interesting phenomena were observed. Approximately 80% of calcium ions stably existed in the solution up to 60 min after amorphous calcium carbonate was separated by centrifugation, and induction time was significantly affected by concentration and feeding rate of sodium carbonate when other operating conditions remained unchanged. Experiments and computer simulation have proved that prenucleation cluster exists during crystallization of calcium carbonate in solutions. This paper tried to figure out specific crystallization process of calcium carbonate under high concentration of magnesium, and to interpret unforeseen phenomena combining with the idea of prenucleation cluster. With regarding prenucleation cluster which can incorporate magnesium into its structure as amorphous calcium carbonate, most of the phenomena including significant influence of local mixing could be better understood. Prenucleation cluster played an important role in crystallization of calcium carbonate, which was related to the induction time, morphology and final product, thus more fundamental studies of prenucleation cluster structure and magnesium role in it should be done.

  9. Evaluation of silicon, calcium and magnesium in liquid fertilizers on sorghum growth in the greenhouse

    Directory of Open Access Journals (Sweden)

    Mario A. Araya

    2015-11-01

    Full Text Available The effect of liquid fertilizers with Si, Ca or Mg on the growth of sorghum (Sorghum bicolor was evaluated in an Ultisol under greenhouse conditions. Four liquid fertilizers (two potassium silicates, calcium carbonate and magnesium oxide were applied into the soil in liquids at doses of 2 and 4 ml.pot-1, plus a control, in a randomized unrestricted design with 9 treatments and 4 replicates. Growth variables, assessed 45 days after sowing, were dry weight of root and aerial parts. Analysis of soil and plant at the end of the test was performed. The application of Ca and Mg significantly increased growth and nutrient uptake of sorghum. Liquid calcium carbonate promoted the highest values of dry biomass and absorption of N, P, Ca, S, Cu, Zn, Mn and B. Si sources had no significant effects on biomass, except for K silicate with Ca and Mg at the dose of 4 ml.pot-1, which also produced a significant increase in K absorption. Calcium carbonate and magnesium oxide significantly increased soil pH and decreased exchangeable acidity and Al, and also increased Ca or Mg content in the soil.

  10. Determination of Sodium, Potassium, Magnesium, and Calcium Minerals Level in Fresh and Boiled Broccoli and Cauliflower by Atomic Absorption Spectrometry

    Science.gov (United States)

    Nerdy

    2018-01-01

    Vegetables from the cabbage family vegetables consumed by many people, which is known healthful, by eaten raw, boiled, or cooked (stir fry or soup). Vegetables like broccoli and cauliflower contain vitamins, minerals, and fiber. This study aims to determine the decrease percentage of sodium, potassium, magnesium, and calcium minerals level caused by boiled broccoli and cauliflower by atomic absorption spectrometry. Boiled broccoli and cauliflower prepared by given boiled treatment in boiling water for 3 minutes. Fresh and boiled broccoli and cauliflower carried out dry destruction, followed by quantitative analysis of sodium, potassium, magnesium, and calcium minerals respectively at a wavelength of 589.0 nm; 766.5 nm; 285.2 nm; and 422.7 nm, using atomic absorption spectrometry methods. After the determination of the sodium, potassium, magnesium, and calcium minerals level followed by validation of analytical methods with accuracy, precision, linearity, range, limit of detection (LOD), and limit of quantitation (LOQ) parameters. Research results show a decrease in the sodium, potassium, magnesium, and calcium minerals level in boiled broccoli and cauliflower compared with fresh broccoli and cauliflower. Validation of analytical methods gives results that spectrometry methods used for determining sodium, potassium, magnesium, and calcium minerals level are valid. It concluded that the boiled gives the effect of decreasing the minerals level significantly in broccoli and cauliflower.

  11. Calcium and magnesium elimination enhances accumulation of cardenolides in callus cultures of endemic Digitalis species of Turkey.

    Science.gov (United States)

    Sahin, G; Verma, S K; Gurel, E

    2013-12-01

    Elimination of calcium (Ca), magnesium (Mg) or both from the medium of callus cultures of Digitalis davisiana Heywood, Digitalis lamarckii Ivanina, Digitalis trojana Ivanina and Digitalis cariensis Boiss. ex Jaub. et Spach increased cardenolides production. Callus was induced from hypocotyl segments from one-month old seedlings were cultured on MS medium containing 0.5 μg ml(-1) thidiazuron (TDZ) and 0.25 μg ml(-1) indole acetic acid (IAA). After 30 days of culture, callus was transferred in hormone-free MS medium (MSO) as well as Ca or Mg or both were completely eliminated from same medium. The amount of five cardenolides from D. davisiana Heywood, D. lamarckii Ivanina, D. trojana Ivanina and D. cariensis Boiss. ex Jaub. et Spach were compared. Higher amounts of five cardenolides and total cardenolides were obtained when callus of four Digitalis species were incubated on MS medium lacking both Ca and Mg. The mean contents of total cardenolides obtained were in the order of D. lamarckii (2017.97 μg g(-1))>D. trojana (1385.75 μg g(-1))>D. cariensis (1038.65 μg g(-1))>D. davisiana (899.86 μg g(-1)) when both Ca and Mg were eliminated from the medium, respectively. This protocol is useful for development of new strategies for the large-scale production of cardenolides. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  12. [Systemic cytomegalovirus infection: changes in serum calcium and magnesium levels with foscarnet treatment].

    Science.gov (United States)

    Marzal-Alfaro, M B; Manrique-Rodríguez, S; Alcaraz Romero, A; García San Prudencio, M; Fernández-Llamazares, C M

    2015-01-01

    Cytomegalovirus infection is common in cardiac transplant patients. Foscarnet is used, with limited evidence, as second-line treatment after ganciclovir failure in these patients. We describe the case of a paediatric cardiac transplant patient who developed electrolyte disturbances during foscarnet treatment for cytomegalovirus infection. The infection resolved after 6 weeks of treatment. Low ionized calcium and magnesium levels were observed during the drug infusion, which were treated with supplements. The serum levels reverted to normal after drug withdrawal. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  13. Mechanical Properties and Durability of Advanced Environmental Barrier Coatings in Calcium-Magnesium-Alumino-Silicate Environments

    Science.gov (United States)

    Miladinovich, Daniel S.; Zhu, Dongming

    2011-01-01

    Environmental barrier coatings are being developed and tested for use with SiC/SiC ceramic matrix composite (CMC) gas turbine engine components. Several oxide and silicate based compositons are being studied for use as top-coat and intermediate layers in a three or more layer environmental barrier coating system. Specifically, the room temperature Vickers-indentation-fracture-toughness testing and high-temperature stability reaction studies with Calcium Magnesium Alumino-Silicate (CMAS or "sand") are being conducted using advanced testing techniques such as high pressure burner rig tests as well as high heat flux laser tests.

  14. Second hyperpolarizability of delta shaped disubstituted acetylene complexes of beryllium, magnesium, and calcium.

    Science.gov (United States)

    Hatua, Kaushik; Nandi, Prasanta K

    2015-10-01

    Present theoretical study involves the delta shape complexes of beryllium, magnesium, and calcium where the metal atom interacts perpendicularly with disubstituted acetylene. Most of the complexes are found to be fairly stable. The dependence of second-hyperpolarizability on the basis set with increasing polarization and diffuse functions has been examined which showed the importance of 'f-type' type polarization function for heavy metal (Mg, Ca) and 'd-type' polarization function for beryllium. Larger second hyperpolarizability has been predicted for complexes having significant ground state polarization and low lying excited states favoring strong electronic coupling. Transition energy plays the most significant role in modulating the second hyperpolarizability.

  15. The content determination of calcium, magnesium and ascorbic acid in sea buckthorn fruits at vulcan coal dump

    Directory of Open Access Journals (Sweden)

    Andreea BRASOVAN

    2009-11-01

    Full Text Available The study presents data on content determination of calcium, magnesium and ascorbic acid in sea buckthorn fruits collected from Vulcan coal dump. The dump was never covered with soil or fertilizers containing azoth, potassium and phosphorus. The sea buckthorn was planted directly on the sterile and it has an important function in stabilizing the acclivity and fixing the atmospheric azoth with the nodosities on the roots. So, the sea buckthorn becomes widespread plant in coal dumps because it helps to the soil formation. The results obtained after the determination of calcium, magnesium and ascorbic acid from the fruits of this plant were compared with the values already reported in various references, concluding that these differences are insignificant (3.7% for magnesium and 9.4% for calcium. Therefore, the sea buckthorn from the dump can be used in food industry, as well as in pharmaceutics and medicine.

  16. Dietary calcium and magnesium supplements in spontaneously hypertensive rats and isolated arterial reactivity.

    Science.gov (United States)

    Mäkynen, H.; Kähönen, M.; Arvola, P.; Wuorela, H.; Vapaatalo, H.; Pörsti, I.

    1995-01-01

    1. High calcium diet attenuates the development of hypertension but an associated undesirable effect is that Mg2+ loss to the urine is enhanced. Therefore, we studied the effects of high calcium diet alone and in combination with increased magnesium intake on blood pressure and arterial function. 2. Forty-eight young spontaneously hypertensive rats (SHR) were allocated into four groups, the dietary contents of Ca2+ and Mg2+ being: 1.1%, 0.2% (SHR); 2.5%, 0.2% (Ca-SHR); 2.5%, 0.8% (CaMg-SHR); and 1.1%, 0.8% (Mg-SHR), respectively. Development of hypertension was followed for 13 weeks, whereafter electrolyte balance, lymphocyte intracellular free calcium ([Ca2+]i), and mesenteric arterial responses in vitro were examined. Forty normotensive Wistar-Kyoto (WKY) rats were investigated in a similar manner. 3. Calcium supplementation comparably attenuated the development of Lypertension during normal and high magnesium intake in SHR, with an associated reduced lymphocyte [Ca2+]i and increased Mg2+ loss to the urine. 4. Endothelium-dependent arterial relaxation to acetylcholine was augmented in Ca-SHR and CaMg-SHR, while the relaxations to isoprenaline and the nitric oxide donor SIN-1 were similar in all SHR groups. Relaxation responses induced by the return of K+ to the organ bath upon precontractions in K(+)-free solution were used to evaluate the function of arterial Na+, K(+)-ATPase. The rate of potassium relaxation was similar in Ca-SHR and CaMg-SHR and faster than in untreated SHR.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8564205

  17. RGDC Peptide-Induced Biomimetic Calcium Phosphate Coating Formed on AZ31 Magnesium Alloy

    Science.gov (United States)

    Cao, Lin; Wang, Lina; Fan, Lingying; Xiao, Wenjun; Lin, Bingpeng; Xu, Yimeng; Liang, Jun; Cao, Baocheng

    2017-01-01

    Magnesium alloys as biodegradable metal implants have received a lot of interest in biomedical applications. However, magnesium alloys have extremely high corrosion rates a in physiological environment, which have limited their application in the orthopedic field. In this study, calcium phosphate compounds (Ca–P) coating was prepared by arginine–glycine–aspartic acid–cysteine (RGDC) peptide-induced mineralization in 1.5 simulated body fluid (SBF) to improve the corrosion resistance and biocompatibility of the AZ31 magnesium alloys. The adhesion of Ca–P coating to the AZ31 substrates was evaluated by a scratch test. Corrosion resistance and cytocompatibility of the Ca–P coating were investigated. The results showed that the RGDC could effectively promote the nucleation and crystallization of the Ca–P coating and the Ca–P coating had poor adhesion to the AZ31 substrates. The corrosion resistance and biocompatibility of the biomimetic Ca–P coating Mg alloys were greatly improved compared with that of the uncoated sample. PMID:28772717

  18. Bioactive calcium sulfate/magnesium phosphate cement for bone substitute applications.

    Science.gov (United States)

    Yang, Guangyong; Liu, Jianli; Li, Fan; Pan, Zongyou; Ni, Xiao; Shen, Yue; Xu, Huazi; Huang, Qing

    2014-02-01

    A novel calcium sulfate/magnesium phosphate cement (CSMPC) composite was prepared and studied in the present work. The physical properties including the phases, the microstructures, the setting properties and the compressive strengths of the CSMPCs were studied. The bio-performances of the CSMPCs were comprehensively evaluated using in vitro simulated body fluid (SBF) method and in vitro cell culture. The dependence of the physical and chemical properties of the CSMPC on its composition and microstructure was studied in detail. It is found that the CSMPC composites exhibited mediate setting times (6-12 min) compared to the calcium sulfate (CS) and the magnesium phosphate cement (MPC). They showed an encapsulation structure in which the unconverted hexagonal prism CSH particles were embedded in the xerogel-like MPC matrix. The phase compositions and the mechanical properties of the CSMPCs were closely related to the content of MPC and the hardening process. The CSMPCs exhibited excellent bioactivity and good biocompatibility to support the cells to attach and proliferate on the surface. The CSMPC composite has the potential to serve as bone grafts for the bone regeneration. © 2013.

  19. Bioactive calcium sulfate/magnesium phosphate cement for bone substitute applications

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Guangyong [Department of Orthopaedics, Taizhou Hospital of Zhejiang Province, Linhai Zhejiang, 317000 (China); Department of Orthopaedic Surgery, Second Affiliated Hospital of Wenzhou Medical College, Wenzhou, Zhejiang, 325000 (China); Liu, Jianli [Trauma Center, Affiliated Hospital of Hainan Medical University, Haikou, Hainan, 570206 (China); Division of Functional Materials and Nanodevices, Ningbo Institute of Materials Technology and Engineering (NIMTE), Chinese Academy of Sciences (CAS), Ningbo, Zhejiang, 315201 (China); Li, Fan; Pan, Zongyou; Ni, Xiao; Shen, Yue [Department of Orthopaedic Surgery, Second Affiliated Hospital of Wenzhou Medical College, Wenzhou, Zhejiang, 325000 (China); Xu, Huazi, E-mail: spinexu@163.com [Department of Orthopaedic Surgery, Second Affiliated Hospital of Wenzhou Medical College, Wenzhou, Zhejiang, 325000 (China); Huang, Qing, E-mail: huangqing@nimte.ac.cn [Division of Functional Materials and Nanodevices, Ningbo Institute of Materials Technology and Engineering (NIMTE), Chinese Academy of Sciences (CAS), Ningbo, Zhejiang, 315201 (China)

    2014-02-01

    A novel calcium sulfate/magnesium phosphate cement (CSMPC) composite was prepared and studied in the present work. The physical properties including the phases, the microstructures, the setting properties and the compressive strengths of the CSMPCs were studied. The bio-performances of the CSMPCs were comprehensively evaluated using in vitro simulated body fluid (SBF) method and in vitro cell culture. The dependence of the physical and chemical properties of the CSMPC on its composition and microstructure was studied in detail. It is found that the CSMPC composites exhibited mediate setting times (6–12 min) compared to the calcium sulfate (CS) and the magnesium phosphate cement (MPC). They showed an encapsulation structure in which the unconverted hexagonal prism CSH particles were embedded in the xerogel-like MPC matrix. The phase compositions and the mechanical properties of the CSMPCs were closely related to the content of MPC and the hardening process. The CSMPCs exhibited excellent bioactivity and good biocompatibility to support the cells to attach and proliferate on the surface. The CSMPC composite has the potential to serve as bone grafts for the bone regeneration. - Highlights: • The mechanical strength and degradation rate of CSMPC composites are discussed. • The CSMPC composites exhibited good bioactivity to form bone-like apatite. • The CSMPC composites also show good biocompatibility.

  20. Dynamical behaviors of structural, constrained and free water in calcium- and magnesium-silicate-hydrate gels.

    Science.gov (United States)

    Le, Peisi; Fratini, Emiliano; Ito, Kanae; Wang, Zhe; Mamontov, Eugene; Baglioni, Piero; Chen, Sow-Hsin

    2016-05-01

    The mechanical properties of cement pastes depend strongly on their porosities. In a saturated paste, the porosity links to the free water volume after hydration. Structural water, constrained water, and free water have different dynamical behavior. Hence, it should be possible to extract information on pore system by exploiting the water dynamics. We investigated the slow dynamics of hydration water confined in calcium- and magnesium-silicate-hydrate (C-S-H and M-S-H) gels using high-resolution quasi-elastic neutron scattering (QENS) technique. C-S-H and M-S-H are the chemical binders present in calcium rich and magnesium rich cements. We measured three M-S-H samples: pure M-S-H, M-S-H with aluminum-silicate nanotubes (ASN), and M-S-H with carboxyl group functionalized ASN (ASN-COOH). A C-S-H sample with the same water content (i.e. 0.3) is also studied for comparison. Structural water in the gels contributes to the elastic component of the QENS spectrum, while constrained water and free water contribute the quasi-elastic component. The quantitative analysis suggests that the three components vary for different samples and indicate the variance in the system porosity, which controls the mechanical properties of cement pastes. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Biodegradable Orthopedic Magnesium-Calcium (MgCa Alloys, Processing, and Corrosion Performance

    Directory of Open Access Journals (Sweden)

    Yuebin Guo

    2012-01-01

    Full Text Available Magnesium-Calcium (Mg-Ca alloy has received considerable attention as an emerging biodegradable implant material in orthopedic fixation applications. The biodegradable Mg-Ca alloys avoid stress shielding and secondary surgery inherent with permanent metallic implant materials. They also provide sufficient mechanical strength in load carrying applications as opposed to biopolymers. However, the key issue facing a biodegradable Mg-Ca implant is the fast corrosion in the human body environment. The ability to adjust degradation rate of Mg-Ca alloys is critical for the successful development of biodegradable orthopedic implants. This paper focuses on the functions and requirements of bone implants and critical issues of current implant biomaterials. Microstructures and mechanical properties of Mg-Ca alloys, and the unique properties of novel magnesium-calcium implant materials have been reviewed. Various manufacturing techniques to process Mg-Ca based alloys have been analyzed regarding their impacts on implant performance. Corrosion performance of Mg-Ca alloys processed by different manufacturing techniques was compared. In addition, the societal and economical impacts of developing biodegradable orthopedic implants have been emphasized.

  2. Determination of thermodynamic parameters for complexation of calcium and magnesium with chondroitin sulfate isomers using isothermal titration calorimetry: Implications for calcium kidney-stone research

    Science.gov (United States)

    Rodgers, Allen L.; Jackson, Graham E.

    2017-04-01

    Chondroitin sulfate (CS) occurs in human urine. It has several potential binding sites for calcium and as such may play an inhibitory role in calcium oxalate and calcium phosphate (kidney stone disease by reducing the supersaturation (SS) and crystallization of these salts. Urinary magnesium is also a role player in determining speciation in stone forming processes. This study was undertaken to determine the thermodynamic parameters for binding of the disaccharide unit of two different CS isomers with calcium and magnesium. These included the binding constant K. Experiments were performed using an isothermal titration calorimeter (ITC) at 3 different pH levels in the physiological range in human urine. Data showed that interactions between the CS isomers and calcium and magnesium occur via one binding site, thought to be sulfate, and that log K values are 1.17-1.93 and 1.77-1.80 for these two metals respectively. Binding was significantly stronger in Mg-CS than in Ca-CS complexes and was found to be dependent on pH in the latter but not in the former. Furthermore, binding in Ca-CS complexes was dependent on the location of the sulfate binding site. This was not the case in the Mg-CS complexes. Interactions were shown to be entropy driven and enthalpy unfavourable. These findings can be used in computational modeling studies to predict the effects of the calcium and magnesium CS complexes on the speciation of calcium and the SS of calcium salts in real urine samples.

  3. CALCIUM AND MAGNESIUM CONCENTRATION OF BREAST MILK IN RELATION WITH AGE AND PARITY OF NURSING WOMEN

    Directory of Open Access Journals (Sweden)

    Zofia Goc

    2012-08-01

    Full Text Available The aim of this study was determination of the concentration of calcium and magnesium in human milk (n=150 taken from nursing women who lived permanently in Malopolska district (South Poland. Milk samples were classified into groups taking into account women’ age and parity. According to the various age of the women milk samples were segregated into three groups: 20-25 years old, 26-31 years old and 32-37 years old. Included parity milk samples were spitted into two groups: the first group consisted of women who were primiparous (1 baby, the second group included women who were multiparous (≥2 babies. Milk samples were taken between the 7th and 14th day of the postpartum in each age group. The samples were taken by manual expression every morning. The analyses of metals were done by flame atomic absorption spectrophotometry (FAAS, after all samples had been collected. The mean concentration of cooper in milk taken from women of first age group (20-25 years old was 209.44±15.10 mg/L, in second group (26-31 years old was 238.65±13.34 mg/L and in the oldest group (32-37 years old was 261.44±17.16 mg/L. The mean concentration of magnesium in the same group of age was 42.12±3.793 mg/L, 47.51±2.728 mg/L and 45.43±3.840 mg/L, respectively. The mean concentration of calcium in milk taken from primiparous was 223.17±10.50mg/L, in multiparous was 266.37±16.20 mg/L. Whereas, the mean concentration of magnesium in transitional milk taken from the same group was 44.12±2.58 mg/L and 47.412±3.16 mg/L, respectively. Statistical analyses showed that there were statistically significant differences between calcium level in milk taken from the youngest group and the concentration of this metal in milk from the oldest group (p=0.032. Also, when comparing women’s parity, significant differences were found in the concentration of calcium (p=0.022. However, the differences in magnesium levels between tested groups were no statistically significant

  4. Corrosion Protection Properties and Mechanism of Epoxy/Acetic Acid-Doped Polyaniline Coating on Magnesium Alloy.

    Science.gov (United States)

    Jin, Tao; Wang, Yanmin; Yin, Hong; Hao, Xiaojuan

    2018-07-01

    Poly(amidoamine)(PAMAM)/epoxy/acetic acid-doped polyaniline (PAni) coatings were successfully prepared and coated on magnesium alloy substrates. X-ray diffraction pattern, Fourier transform infrared spectroscopy, scanning electron microscopy technique were used to characterize the composition and morphology of acetic acid-doped PAni and composite coatings. The effect of the usage amount of doped PAni on the corrosion protection performance was evaluated with electrochemical measurement in 3.5 wt.% NaCl solutions. Tafel and electrochemical impedance spectroscopy analysis revealed that the addition of 1.0 wt.% doped PAni provided the superior corrosion protection properties. The corrosion protection mechanism was investigated by using electron probe microanalysis test and theoretical physical model. The doped PAni could obviously shrink the pits and made epoxy resin matrix denser by cross-linking and hydrogen bonding. The composite coatings exhibited better corrosion protection properties compared to pure epoxy coating. The in situ generated corrosion products provided anodic corrosion inhibition due to the easier penetration of acetate ions, and better physical barrier mechanism was promoted by the addition of doped PAni.

  5. Effects of calcium and magnesium hardness on the fertilization and hatching success of channel X blue hybrid catfish eggs

    Science.gov (United States)

    The aquifer used for hybrid catfish hatcheries is less than 10 mg/L of calcium hardness and 1- 25 mg/L of magnesium hardness. Embryonic development is deemed to be the most sensitive stage in the life cycle of a teleost. As egg development takes outside the fish’s body, water hardness is one abioti...

  6. A comparative study of serum uric acid, glucose, calcium and magnesium in pre-eclampsia and normal pregnancy

    Directory of Open Access Journals (Sweden)

    Arun Dhungana

    2017-09-01

    Full Text Available Background: Preeclampsia is associated with liver function abnormalities and renal function impairment. The objective of this study is to compare serum uric acid, glucose, calcium and magnesium in pre-eclampsia with normal pregnancy. Materials and Methods: Normal pregnant women and pre eclamptic women of age group 20-40 years were included. Serum magnesium, calcium, glucose, uric acid were analyzed.Results: Mean serum magnesium level in preeclampsia (1.83 ± 0.21mg/dl was lesser in comparison to normal pregnant women (2.03 ± 0.16 mg/dl. Serum calcium level was lower (8.10 ±0.56mg/dl than control (9.59 ±0.62 mg/dl with p<0.001. Uric acid, glucose and lactate dehydrogenase in preeclamptic women was significantly higher than that in normal pregnant women (6.14 ± 0.85 vs.4.01 ± 0.62, p=<0.001, (94.17± 18.65 vs.86.34 ± 10.19, p=0.033 and ( 466.80 ± 97.29 vs. 194.22 ± 39.76, p=<0.001 respectively.Conclusion: There were significant changes in serum magnesium, uric acid, calcium, glucose, lactate dehydrogenase and total protein in pregnant women.

  7. On the distribution of fluoride, calcium and magnesium in the waters off the central west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Naik, S.; Dias, C.F.M.

    The distribution of fluoride, calcium and magnesium was studied in the waters off the central west coast of India. The averages F/Cl, Ca/Cl and Mg/Cl ratios observed are (6.83 plus or minus 0.023) x 10@u-5@@, (0.02194 plus or minus 0.00068) and (0...

  8. Expression of Trans- and Paracellular Calcium and Magnesium Transport Proteins in Renal and Intestinal Epithelia During Lactation

    DEFF Research Database (Denmark)

    Beggs, Megan R; Appel, Ida; Svenningsen, Per

    2017-01-01

    Significant alterations in maternal calcium (Ca2+) and magnesium (Mg2+) balance occur during lactation. Ca2+ is the primary divalent cation mobilized into breast milk by demineralization of the skeleton and alterations in intestinal and renal Ca2+ transport. Mg2+ is also concentrated in breast milk...

  9. Relationship of serum ionized calcium and magnesium concentration with parasympathetic nerve Function in type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Md. Khairul Alam

    2016-12-01

    Full Text Available Background: Changes in serum Ca2+ and Mg2+ level may have some relationship to the occurrence of autonomic neuropathy in diabetes. Objective: To observe relationship between parasympathetic nerve function and serum ionized calcium & magnesium in type 2 diabetes mellitus (T2DM. Methods: This cross sectional study was carried out in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University (BSMMU, Dhaka on 47 T2DM patients aged 40-68 years of both sexes. Twenty five patients were recently diagnosed diabetics (RDM and 22 were long term diabetics (LDM with 10-20 years duration of diabetes. Parasympathetic nerve functions of all patients were assessed by three simple non-invasive cardiovascular reflex tests. Ionized serum calcium and magnesium were measured by ion sensitive electrode method using NOVA electrode. Data were analyzed by unpaired‘t’test and Pearson’s correlation co-efficient test. Results: Serum ionized calcium and magnesium levels were significantly higher in RDM (P<0.001 and LDM (P<0.001 compared to healthy control. On correlation analysis, significant negative correlation of parasympathetic nerve function with Mg2+was found in both RDM and LDM patients. Conclusion: The result of this study concluded that higher calcium and magnesium ion may be associated with type 2 diabetes and parasympathetic nerve function of diabetic patients may have inverse relationship to serum Mg2+.

  10. Serum magnesium and calcium in preeclampsia: a comparative study at the Korle-Bu Teaching Hospital, Ghana

    Directory of Open Access Journals (Sweden)

    Owusu Darkwa E

    2017-08-01

    Full Text Available Ebenezer Owusu Darkwa,1 Charles Antwi-Boasiako,2 Robert Djagbletey,1 Christian Owoo,1 Samuel Obed,3,† Daniel Sottie4 1Department of Anaesthesia, University of Ghana School of Medicine and Dentistry, 2Department of Physiology, University of Ghana School of Biomedical and Allied Health Sciences, 3Department of Obstetrics and Gynaecology, University of Ghana School of Medicine and Dentistry, College of Health Sciences, 4Department of Anaesthesia, Korle-Bu Teaching Hospital, Accra, Ghana †Samuel Obed passed away on May 12, 2017 Background: A large percentage (16% of maternal mortality in developed countries, compared to 9% in developing countries, is due to hypertensive disorders in pregnancy. The etiology of preeclampsia remains unknown, with poorly understood pathophysiology. Magnesium and calcium play an important role in vascular smooth muscle function and therefore a possible role in the development of preeclampsia.Aim: We aimed to compare serum magnesium and total calcium levels of preeclamptic and normal pregnant women at the Korle-Bu Teaching Hospital in Ghana.Patients and methods: A comparative cross-sectional study involving 30 normal pregnant and 30 preeclamptic women with >30 weeks gestation and aged 18–35 years, was conducted at the Korle-Bu Teaching Hospital. Magnesium and calcium were determined using a flame atomic absorption spectrometer.Results: Mean serum magnesium and total calcium levels in preeclamptic women were 0.70±0.15 and 2.13±0.30 mmol/L, respectively. Mean serum magnesium and total calcium levels in normal pregnant women were 0.76±0.14 and 2.13±0.35 mmol/L, respectively. There was a statistically nonsignificant difference in serum magnesium and total calcium in preeclamptic women compared to normal pregnant women, with p-values of 0.092 and 0.972, respectively.Conclusion: Serum magnesium and total calcium, therefore, seem not to differ in preeclamptic women compared to normal pregnant women in Ghana

  11. Rapid coating of AZ31 magnesium alloy with calcium deficient hydroxyapatite using microwave energy

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Yufu, E-mail: Yufu.Ren@rockets.utoledo.edu [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Zhou, Huan [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Institute of Biomedical Engineering and Health Sciences, Changzhou University, Changzhou, Jiangsu (China); Nabiyouni, Maryam [Department of Bioengineering, The University of Toledo, Toledo, OH (United States); Bhaduri, Sarit B. [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Division of Dentistry, The University of Toledo, Toledo, OH (United States)

    2015-04-01

    Due to their unique biodegradability, magnesium alloys have been recognized as suitable metallic implant materials for degradable bone implants and bioresorbable cardiovascular stents. However, the extremely high degradation rate of magnesium alloys in physiological environment has restricted its practical application. This paper reports the use of a novel microwave assisted coating technology to improve the in vitro corrosion resistance and biocompatibility of Mg alloy AZ31. Results indicate that a dense calcium deficient hydroxyapatite (CDHA) layer was uniformly coated on a AZ31 substrate in less than 10 min. Weight loss measurement and SEM were used to evaluate corrosion behaviors in vitro of coated samples and of non-coated samples. It was seen that CDHA coatings remarkably reduced the mass loss of AZ31 alloy after 7 days of immersion in SBF. In addition, the prompt precipitation of bone-like apatite layer on the sample surface during immersion demonstrated a good bioactivity of the CDHA coatings. Proliferation of osteoblast cells was promoted in 5 days of incubation, which indicated that the CDHA coatings could improve the cytocompatibility of the AZ31 alloy. All the results suggest that the CDHA coatings, serving as a protective layer, can enhance the corrosion resistance and biological response of magnesium alloys. Furthermore, this microwave assisted coating technology could be a promising method for rapid surface modification of biomedical materials. - Highlights: • A microwave assisted coating process for biodegradable Mg alloy. • CDHA coatings were successfully developed on AZ31 alloy in minutes. • The as-deposited CDHA coatings significantly reduced the degradation rate of AZ31 alloy. • The CDHA coated AZ31 alloy showed good bioactivity and biocompatibility in vitro. • The microwave assisted coating process can be used as rapid surface modification for bioimplants.

  12. Calcium-magnesium Aluminosilicate (CMAS) Interactions with Advanced Environmental Barrier Coating Material

    Science.gov (United States)

    Wiesner, Valerie L.; Bansal, Narottam P.

    2015-01-01

    Particulates, like sand and volcanic ash, threaten the development of robust environmental barrier coatings (EBCs) that protect next-generation silicon-based ceramic matrix composite (CMC) turbine engine components from harsh combustion environments during service. The siliceous particulates transform into molten glassy deposits of calcium-magnesium aluminosilicate (CMAS) when ingested by an aircraft engine operating at temperatures above 1200C. In this study, a sample of desert sand was melted into CMAS glass to evaluate high-temperature interactions between the sand glass and an advanced EBC material. Desert sand glass was added to the surface of hot-pressed EBC substrates, which were then heated in air at temperatures ranging from 1200C to 1500C. Scanning electron microscopy and X-ray energy-dispersive spectroscopy were used to evaluate microstructure and phase compositions of specimens and the CMASEBC interface after heat treatments.

  13. Influence of calcium and magnesium salts on acid soil chemistry and calcium nutrition of apple

    Energy Technology Data Exchange (ETDEWEB)

    Pavan, M.A.; Bingham, F.T.; Peryea, F.J.

    Field experiments were conducted in two Brazilian orchards to examine the effects of soil applications of calcitic lime (Ca-lime), phosphogypsum, CaCl/sub 2/, and magnesite (Mg-lime) on soil chemistry and Ca nutrition of apple (Malus domestica Borkh, cv. Gala/MM 106). One orchard was on a low Ca, high Al Inceptisol; the second orchard was on a low Ca, low Al Oxisol. The resulting soil chemical changes were strongly influenced by the initial soil chemistry and the composition of the soil amendments. The effects of Ca-lime, added at a rate calculated to neutralize the topsoil exchange acidity, were restricted primarily to the upper 20 cm of the soil, where it increased pH, increased total dissolved and exchangeable Ca, eliminated dissolved Al, and reduced exchangeable Al. Phosphogypsum, added at Ca rates equivalent to the Ca-lime treatment, slightly reduced soil pH in the Inceptisol and slightly increased soil pH in the Oxisol. Phosphogypsum did not appreciably affect dissolved Al in the topsoil; however, it did reduce exchangeable Al but to a lesser degree than did Ca-lime or Mg-lime. Phosphogypsum increased exchangeable Ca and decreased exchangeable Al in the subsoil to a depth of 40 to 60 cm. Calcium chloride, added at Ca rates equivalent to the Ca-lime treatment, produced dissolved and exchangeable Ca increases similar to the phosphogypsum treatment; however, soluble and exchangeable Al were increased and pH slightly decreased through out the soil profiles.

  14. Magnesium modulates parathyroid hormone secretion and upregulates parathyroid receptor expression at moderately low calcium concentration.

    Science.gov (United States)

    Rodríguez-Ortiz, Maria E; Canalejo, Antonio; Herencia, Carmen; Martínez-Moreno, Julio M; Peralta-Ramírez, Alan; Perez-Martinez, Pablo; Navarro-González, Juan F; Rodríguez, Mariano; Peter, Mirjam; Gundlach, Kristina; Steppan, Sonja; Passlick-Deetjen, Jutta; Muñoz-Castañeda, Juan R; Almaden, Yolanda

    2014-02-01

    The interest on magnesium (Mg) has grown since clinical studies have shown the efficacy of Mg-containing phosphate binders. However, some concern has arisen for the potential effect of increased serum Mg on parathyroid hormone (PTH) secretion. Our objective was to evaluate the direct effect of Mg in the regulation of the parathyroid function; specifically, PTH secretion and the expression of parathyroid cell receptors: CaR, the vitamin D receptor (VDR) and FGFR1/Klotho. The work was performed in vitro by incubating intact rat parathyroid glands in different calcium (Ca) and Mg concentrations. Increasing Mg concentrations from 0.5 to 2 mM produced a left shift of PTH-Ca curves. With Mg 5 mM, the secretory response was practically abolished. Mg was able to reduce PTH only if parathyroid glands were exposed to moderately low Ca concentrations; with normal-high Ca concentrations, the effect of Mg on PTH inhibition was minor or absent. After 6-h incubation at a Ca concentration of 1.0 mM, the expression of parathyroid CaR, VDR, FGFR1 and Klotho (at mRNA and protein levels) was increased with a Mg concentration of 2.0 when compared with 0.5 mM. Mg reduces PTH secretion mainly when a moderate low calcium concentration is present; Mg also modulates parathyroid glands function through upregulation of the key cellular receptors CaR, VDR and FGF23/Klotho system.

  15. In vitro and in vivo evaluation of the surface bioactivity of a calcium phosphate coated magnesium alloy.

    Science.gov (United States)

    Xu, Liping; Pan, Feng; Yu, Guoning; Yang, Lei; Zhang, Erlin; Yang, Ke

    2009-03-01

    Magnesium has shown potential application as a bio-absorbable biomaterial, such as for bone screws and plates. In order to improve the surface bioactivity, a calcium phosphate was coated on a magnesium alloy by a phosphating process (Ca-P coating). The surface characterization showed that a porous and netlike CaHPO(4).2H(2)O layer with small amounts of Mg(2+) and Zn(2+) was formed on the surface of the Mg alloy. Cells L929 showed significantly good adherence and significantly high growth rate and proliferation characteristics on the Ca-P coated magnesium alloy (p<0.05) in in-vitro cell experiments, demonstrating that the surface cytocompatibility of magnesium was significantly improved by the Ca-P coating. In vivo implantations of the Ca-P coated and the naked alloy rods were carried out to investigate the bone response at the early stage. Both routine pathological examination and immunohistochemical analysis demonstrated that the Ca-P coating provided magnesium with a significantly good surface bioactivity (p<0.05) and promoted early bone growth at the implant/bone interface. It was suggested that the Ca-P coating might be an effective method to improve the surface bioactivity of magnesium alloy.

  16. Effects of low calcium plus high aluminum diet on magnesium and calcium contents in spinal cord and trabecular bone of rats

    Energy Technology Data Exchange (ETDEWEB)

    Yasui, Masayuki; Ota, Kiichiro [Wakayama Medical Coll. (Japan); Sasajima, Kazuhisa

    1998-01-01

    Current epidemiological surveys in the Western Pacific area and Kii Peninsula have suggested that low calcium (Ca), magnesium (Mg), and high aluminum (Al) and manganese (Mn) in river, soil and drinking water may be implicated in the pathogenetic process of amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia (PD). The condition of unbalanced minerals was experimentally duplicated in this study using rats. Male Wistar rats, weighing 200 g, were maintained for 60 days on the following diets: (A) standard diet, (B) low Ca diet, (C) low Ca diet with high Al. Magnesium concentration was determined in spinal cord and trabecular bone using inductively coupled plasma emission spectrometry (ICP) and the calcium concentration was determined using neutron activation method. In the group maintained on low Ca high Al diet, magnesium content of the spinal cord was lower than the group fed standard diet. Also, magnesium content of lumbar bone showed lower values in the unbalanced diet group fed low Ca high Al diet than those in the standard diet and low Ca diet groups. Calcium content of spinal cord was highest in rats maintained on low Ca high Al diet. Calcium content in lumbar bone of rats significantly decreased in rats maintained on the low Ca diet (group B and C) compared to rats given a standard diet (group A). Our data indicate that low Ca and high Al dietary intake influence Mg concentration in bone and central nervous system (CNS) tissues and that low Ca and high Al diet diminish Mg in bone and CNS tissues, thereby inducing loss of calcification in bone and degeneration of CNS tissues due to disturbance of the normal biological effects of Mg. (author)

  17. Coadministration of calcium chloride with lead acetate can improve motility of cauda epididymal spermatozoa in Swiss white mice

    Directory of Open Access Journals (Sweden)

    Farhad Golshan Iranpour

    2016-02-01

    Full Text Available Background: Lead is an industrial heavy metal that can decrease sperm motility. Objective: The aim was to investigate the protective effects of calcium against lead on motility of spermatozoa. Materials and Methods: In total 40 adult male Swiss white mice were randomly divided into 5 groups (control, lead of 1PstP wk, lead of 2PndP wk, lead/calcium of 1Pst Pwk and lead/calcium of 2PndP wk. The lead groups of mice were injected by a single dose of lead acetate (200 mg/kg intraperitoneally. Lead/calcium groups of mice were injected by a single same dose of lead acetate along with three doses of 80 mg/kg calcium chloride. The control group of mice was injected only with same volume of distilled water through the same route. Mice of 1PstP and 2PndP wk groups were sacrificed through cervical dislocation one and two weeks after injections respectively. Results: Mean of the progressive motile spermatozoa of cauda epididymis in lead/calcium group of the first week was higher than the lead group of the first week and this difference was significant. There was not any significant difference among weight of testes and epididymides of all groups. Conclusion: It can be concluded that calcium can decrease the effects of lead on sperm motility.

  18. Amino Acid Medical Foods Provide a High Dietary Acid Load and Increase Urinary Excretion of Renal Net Acid, Calcium, and Magnesium Compared with Glycomacropeptide Medical Foods in Phenylketonuria

    National Research Council Canada - National Science Library

    Bridget M. Stroup; Emily A. Sawin; Sangita G. Murali; Neil Binkley; Karen E. Hansen; Denise M. Ney

    2017-01-01

    .... We tested the hypothesis that amino acid medical foods (AA-MF) provide a high dietary acid load, subsequently increasing urinary excretion of renal net acid, calcium, and magnesium, compared to glycomacropeptide medical foods (GMP-MF). Design...

  19. Preparation of amorphous calcium-magnesium phosphates at pH 7 and characterization by x-ray absorption and fourier transform infrared spectroscopy

    NARCIS (Netherlands)

    Holt, C.; Kemenade, M.J.J.M. van; Harries, J.E.; Nelson, L.S.; Bailey, R.T.; Hukins, D.W.L.; Hasnain, S.S.; Bruyn, P.L. de

    1988-01-01

    Amorphous calcium-magnesium phosphates were prepared by precipitation from moderately supersaturated aqueous solutions at pH 7. Chemical analysis of the samples by ion chromatography showed that up to about 50% of the phosphate ions were protonated, the proportion increasing with the magnesium to

  20. Nationwide data on municipal drinking water and hip fracture: could calcium and magnesium be protective? A NOREPOS study.

    Science.gov (United States)

    Dahl, Cecilie; Søgaard, Anne Johanne; Tell, Grethe S; Flaten, Trond Peder; Hongve, Dag; Omsland, Tone Kristin; Holvik, Kristin; Meyer, Haakon E; Aamodt, Geir

    2013-11-01

    Norway has a high incidence of hip fractures, and the incidence varies by degree of urbanization. This variation may reflect a difference in underlying environmental factors, perhaps variations in the concentration of calcium and magnesium in municipal drinking water. A trace metal survey (1986-1991) in 556 waterworks (supplying 64% of the Norwegian population) was linked geographically to hip fractures from hospitals throughout the country (1994-2000). In all, 5472 men and 13,604 women aged 50-85years suffered a hip fracture. Poisson regression models were fitted, adjusting for age, urbanization degree, region of residence, type of water source, and pH. The concentrations of calcium and magnesium in drinking water were generally low. An inverse association was found between concentration of magnesium and risk of hip fracture in both genders (IRR men highest vs. lowest tertile=0.80, 95% CI: 0.74, 0.87; IRR women highest vs. lowest tertile=0.90, 95% CI: 0.85, 0.95), but no consistent association between calcium and hip fracture risk was observed. The highest tertile of urbanization degree (city), compared to the lowest (rural), was related to a 23 and 24% increase in hip fracture risk in men and women, respectively. The association between magnesium and hip fracture did not explain the variation in hip fracture risk between city and rural areas. Magnesium in drinking water may have a protective role against hip fractures; however this association should be further investigated. © 2013 Elsevier Inc. All rights reserved.

  1. Effect of Spirulina maxima Supplementation on Calcium, Magnesium, Iron, and Zinc Status in Obese Patients with Treated Hypertension.

    Science.gov (United States)

    Suliburska, J; Szulińska, M; Tinkov, A A; Bogdański, P

    2016-09-01

    The effects of Spirulina maxima supplementation on calcium, magnesium, iron, and zinc status were studied in a double-blind placebo-controlled trial of 50 obese subjects with treated hypertension, each randomized to receive 2 g of spirulina or a placebo daily for 3 months. At baseline and after treatment, the calcium, magnesium, iron, and zinc concentration in plasma was assessed. It was found that 3 months of S. maxima supplementation resulted in a significant decrease in the iron level in the plasma of obese patients. In conclusion, this is the first clinical study on the influence of spirulina supplementation on mineral status in obese patients with hypertension. Spirulina supplementation affects the iron status of obese Caucasians with well-treated hypertension.

  2. Influence of ethanol content in the precipitation medium on the composition, structure and reactivity of magnesium-calcium phosphate.

    Science.gov (United States)

    Babaie, Elham; Zhou, Huan; Lin, Boren; Bhaduri, Sarit B

    2015-08-01

    Biocompatible amorphous magnesium calcium phosphate (AMCP) particles were synthesized using ethanol in precipitation medium from moderately supersaturated solution at pH10. Some synthesis parameters such as, (Mg+Ca):P, Mg:Ca ratio and different drying methods on the structure and stability of as-produced powder was studied and characterized using SEM, XRD and cell cytocompatibility. The results showed that depending on the Mg(2+) concentration, nano crystalline Struvite (MgNH4PO4·6H2O) can also be alternatively formed. However, the as-formed AMCP preserved its amorphous structure after 7 days of incubation in SBF for tested phosphate concentration, and equally ionic concentration of magnesium and calcium. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Assessment of salivary calcium, phosphate, magnesium, pH, and flow rate in healthy subjects, periodontitis, and dental caries

    Directory of Open Access Journals (Sweden)

    K S Rajesh

    2015-01-01

    Full Text Available Aim: This study was conducted to estimate and compare inorganic salivary calcium, phosphate, magnesium, salivary flow rate, and pH of unstimulated saliva and oral hygiene status of healthy subjects, subjects with periodontitis and dental caries, and to correlate salivary calcium level with number of intact teeth. Materials and Methods: The study population consisted of 48 systemically healthy subjects in the age group of 18-55 years, which was further divided into three groups: healthy, periodontitis, and dental caries. Oral hygiene index-simplified, probing pocket depth, clinical attachment level, the number of intact teeth, and active carious lesions were recorded. Estimation of inorganic salivary calcium, phosphate, and magnesium was performed spectrophotometrically using Vitros 5.1 FS. Statistical analysis was performed using the one-way analysis of variance test at 5% significance level. Results: There was a statistically significant increase in inorganic salivary calcium, phosphate, pH, flow rate, and poor oral hygiene status in periodontitis group compared to dental caries and healthy group. Conclusion: Subjects with increased inorganic salivary calcium, phosphate, pH, flow rate, and poor oral hygiene are at a higher risk of developing periodontitis. Since there is increased remineralization potential, these subjects have more number of intact teeth compared to the dental caries group.

  4. Effect of calcium and magnesium silicate on the growth of the castor oil plant subjected to salinity levels

    OpenAIRE

    de Brito Neto, Jose Felix [UNESP; Macedo Beltrao, Napoleao de Esberard; Gonsiorkiewicz Rigon, Joao Paulo [UNESP; Capuani, Silvia [UNESP

    2012-01-01

    Salt stress decreases the osmotic potential of soil solution causing water stress, causing toxic effects in the plants resulting in injuries on the metabolism and nutritional disorders, thus compromising the plant growth, resulting in lower production. The calcium silicate and magnesium can perform the same function as limestone, besides providing silicon to plants, may also contribute to the resistance of plants to salt stress. Thus, the objective of this study was to evaluate the effect of ...

  5. Electrochemical characteristics of calcium-phosphatized AZ31 magnesium alloy in 0.9 % NaCl solution.

    Science.gov (United States)

    Hadzima, Branislav; Mhaede, Mansour; Pastorek, Filip

    2014-05-01

    Magnesium alloys suffer from their high reactivity in common environments. Protective layers are widely created on the surface of magnesium alloys to improve their corrosion resistance. This article evaluates the influence of a calcium-phosphate layer on the electrochemical characteristics of AZ31 magnesium alloy in 0.9 % NaCl solution. The calcium phosphate (CaP) layer was electrochemically deposited in a solution containing 0.1 M Ca(NO3)2, 0.06 M NH4H2PO4 and 10 ml l(-1) of H2O2. The formed surface layer was composed mainly of brushite [(dicalcium phosphate dihidrate (DCPD)] as proved by energy-dispersive X-ray analysis. The surface morphology was observed by scanning electron microscopy. Immersion test was performed in order to observe degradation of the calcium phosphatized surfaces. The influence of the phosphate layer on the electrochemical characteristics of AZ31, in 0.9 % NaCl solution, was evaluated by potentiodynamic measurements and electrochemical impedance spectroscopy. The obtained results were analysed by the Tafel-extrapolation method and equivalent circuits method. The results showed that the polarization resistance of the DCPD-coated surface is about 25 times higher than that of non-coated surface. The CaP electro-deposition process increased the activation energy of corrosion process.

  6. Calcium-Magnesium-Aluminosilicate (CMAS) Reactions and Degradation Mechanisms of Advanced Environmental Barrier Coatings

    Science.gov (United States)

    Ahlborg, Nadia L.; Zhu, Dongming

    2013-01-01

    The thermochemical reactions between calcium-magnesium-aluminosilicate- (CMAS-) based road sand and several advanced turbine engine environmental barrier coating (EBC) materials were studied. The phase stability, reaction kinetics and degradation mechanisms of rare earth (RE)-silicates Yb2SiO5, Y2Si2O7, and RE-oxide doped HfO2 and ZrO2 under the CMAS infiltration condition at 1500 C were investigated, and the microstructure and phase characteristics of CMAS-EBC specimens were examined using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). Experimental results showed that the CMAS dissolved RE-silicates to form crystalline, highly non-stoichiometric apatite phases, and in particular attacking the silicate grain boundaries. Cross-section images show that the CMAS reacted with specimens and deeply penetrated into the EBC grain boundaries and formed extensive low-melting eutectic phases, causing grain boundary recession with increasing testing time in the silicate materials. The preliminary results also showed that CMAS reactions also formed low melting grain boundary phases in the higher concentration RE-oxide doped HfO2 systems. The effect of the test temperature on CMAS reactions of the EBC materials will also be discussed. The faster diffusion exhibited by apatite and RE-doped oxide phases and the formation of extensive grain boundary low-melting phases may limit the CMAS resistance of some of the environmental barrier coatings at high temperatures.

  7. The influence of calcium, magnesium, phosphorus and silica on vanadium precipitation in acidic sulfate solutions

    Directory of Open Access Journals (Sweden)

    A. H. Martins

    2000-06-01

    Full Text Available The experimental research work was carried out in accordance with the Factorial Design Statistical Method to evaluate and analyze the influence of calcium, magnesium, silica and phosphorus on the precipitation of vanadates. Precipitation was performed by neutralization with H2SO4 of alkaline aqueous solutions containing vanadium pentoxide (V2O5 at 60± 2ºC. The experimental responses measured were percent of vanadium recovery and vanadium pentoxide content in the precipitate. These impurities are considered representative of those present in a leach liquor from the ore obtained at Campo Alegre de Lourdes (Brazil. The operational variables in this work were used under optimum conditions as determined by the statistical approach. Among the impurities under study, phosphorus exhibited the highest negative influence on the experimental responses. Phosphorus diminished the percent of vanadium recovered from 98.9 to 34.5 and the vanadium oxide content in the precipitate from 91.2 % to 39.3 %.

  8. Brain copper, iron, magnesium, zinc, calcium, sulfur and phosphorus storage in Wilson's disease.

    Science.gov (United States)

    Faa, G; Lisci, M; Caria, M P; Ambu, R; Sciot, R; Nurchi, V M; Silvagni, R; Diaz, A; Crisponi, G

    2001-01-01

    Wilson's disease (WD) is an inherited disorder of copper metabolism characterised by juvenile liver cirrhosis and by neurological symptoms. Copper levels in brain in WD have been reported to be 10 to 15 fold normal values, depending on the different brain regions. Being very few data on copper distribution in central nervous system in WD available, it seemed of interest to study the concentration of copper and of other trace elements (Zn, P, Mg, Ca, Fe and S) in the brain of a patient died for WD. a 56 year old woman affected by WD was admitted to our hospital with signs of hepatic failure and died few days later. At autopsy, a brain slice extending from the left to the right hemisphere was divided in 28 samples. On each sample Copper, Iron, Magnesium, Phosphorus, Sulphur, Zinc and Calcium were determined by Induced Coupled Plasma Atomic Emission Spectroscopy. the mean concentration of copper, ranging from 88 to 158 microg/g of dry tissue in all the brain specimens was higher than literature reference values, while that of the other tested elements was considerably lower. 1) In the brain of WD patient examined the status of trace elements was extensively altered. Further studies are necessary to correlate the concentration of trace elements with pathological lesions and with clinical pictures. 2) The elements considered in our study showed an uneven distribution in different brain areas.

  9. Calcium and magnesium content in hard tissues of rats under condition of subchronic lead intoxication.

    Science.gov (United States)

    Todorovic, Tatjana; Vujanovic, Dragana; Dozic, Ivan; Petkovic-Curcin, Aleksandra

    2008-03-01

    Lead manifests toxic effects in almost all organs and tissues, especially in: the nervous system, hematopoietic system, kidney and liver. This metal has a special affinity for deposition in hard tissue, i.e., bones and teeth. It is generally believed that the main mechanism of its toxicity relies on its interaction with bioelements, especially with Ca and Mg. This article analyses the influence of Pb poisoning on Ca and Mg content in hard tissues, (mandible, femur, teeth and skull) of female and young rats. Experiments were carried out on 60 female rats, AO breed, and on 80 of their young rats (offspring). Female rats were divided into three groups: the first one was a control group, the second one received 100 mg/kg Pb2+ kg b.wt. per day in drinking water, the third one received 30 mg/kg Pb(2+) kg b.wt. per day in drinking water. Young rats (offspring) were divided into the same respective three groups. Lead, calcium and magnesium content in hard tissues (mandible, femur, teeth-incisors and skull) was determined by flame atomic absorption spectrophotometry in mineralized samples. There was a statistically significant Pb deposition in all analyzed female and young rat hard tissues. Ca and Mg contents were significantly reduced in all female and young rat hard tissues. These results show that Pb poisoning causes a significant reduction in Ca and Mg content in animal hard tissues, which is probably the consequence of competitive antagonism between Pb and Ca and Mg.

  10. Calcium, magnesium, iron, zinc and copper concentration in the hair of tobacco smokers.

    Science.gov (United States)

    Unkiewicz-Winiarczyk, Aneta; Bagniuk, Anna; Gromysz-Kałkowska, Kazimiera; Szubartowska, Ewa

    2009-05-01

    In the research, the content of bioelements (Ca, Mg, Fe, Zn, and Cu) in the hair of individuals who reside in similar environmental conditions was spectrometrically determined with the use of AES-ICP spectrophotometer. The relation to their tobacco-smoking habit, age, and sex was established. It was observed that the results obtained were in the range of the content identified for the Polish population. Tobacco smokers had a decreased content of all the bioelements in question, compared to non-smokers, which apparently resulted from a decreased supply (lesser appetite) and reduced absorption caused by disturbances in the digestive system functions. Also, it has been observed that in the group of elderly people, over 50 years old, there was a fall in the content of calcium, magnesium, and iron both in smokers and non-smokers, irrespective of their sex. The sex-related differences in the content of the investigated elements were not unidirectional and only in few cases did they reveal statistical significance.

  11. Calcium and magnesium uptake by oat cultivars subjected to aluminum toxicity levels

    Directory of Open Access Journals (Sweden)

    José Antonio Gonzalez da Silva

    2013-12-01

    Full Text Available Acid soils with high aluminum (Al concentrations affect the productivity of oats and many crops. The toxicity of this cation, besides reducing root growth, interferes on the uptake, transport and use of nutrients such as magnesium (Mg and calcium (Ca. The objective of this work was to evaluate the Ca and Mg uptake ability by measuring their content in the leaf tissues of white oat cultivars. Tolerant and sensitive cultivars were tested under hydroponic culture to verify if the genotypes with greater uptake ability of Ca and Mg do represent those with a tolerant response. In the study, two experiments were performed, one to validate the tolerance groups based on root regrowth and another aiming to reach plant dry masses large enough to determine Ca and Mg. In both situations, the experimental design was completely random at a 3 x 6 factorial for dose and genotype with three replications. The uptake of Ca and Mg are affected by the addition of Al to the hydroponic solution, with tolerant cultivars showing higher concentrations on the leaf tissues than sensitive ones in the absence and presence of Al. Therefore, there is a link between the tolerance levels with the Al uptake, representing a variable to be employed on the selection of more efficient genotypes.

  12. Attributes of the soil fertilized with sewage sludge and calcium and magnesium silicate

    Directory of Open Access Journals (Sweden)

    Geraldo R. Zuba Junio

    2015-11-01

    Full Text Available ABSTRACTThis study aimed to evaluate the chemical attributes of an Inceptisol cultivated with castor bean (Ricinus communis L., variety ‘BRS Energia’, fertilized with sewage sludge compost and calcium (Ca and magnesium (Mg silicate. The experiment was conducted at the ICA/UFMG, in a randomized block design, using a 2 x 4 factorial scheme with three replicates, and the treatments consisted of two doses of Ca-Mg silicate (0 and 1 t ha-1 and four doses of sewage sludge compost (0, 23.81, 47.62 and 71.43 t ha-1, on dry basis. Soil organic matter (OM, pH, sum of bases (SB, effective cation exchange capacity (CEC(t, total cation exchange capacity (CEC(T, base saturation (V% and potential acidity (H + Al were evaluated. There were no significant interactions between doses of sewage sludge compost and doses of Ca-Mg silicate on soil attributes, and no effect of silicate fertilization on these attributes. However, fertilization with sewage sludge compost promoted reduction in pH and increase in H + Al, OM and CEC. The dose of 71.43 t ha-1 of sewage sludge compost promoted the best soil chemical conditions.

  13. A simple bacterial transformation method using magnesium- and calcium-aminoclays.

    Science.gov (United States)

    Choi, Hyoung-An; Lee, Young-Chul; Lee, Jin-Young; Shin, Hyun-Jae; Han, Hyo-Kyung; Kim, Geun-Joong

    2013-11-01

    An efficient and user-friendly bacterial transformation method by simple spreading cells with aminoclays was demonstrated. Compared to the reported transformation approaches using DNA adsorption or wrapping onto (in)organic fibers, the spontaneously generated clay-coated DNA suprastructures by mixing DNA with aminoclay resulted in transformants in both Gram-negative (Escherichia coli) and Gram-positive cells (Streptococcus mutans). Notably, the wild type S. mutans showed comparable transformation efficiency to that of the E. coli host for recombinant DNA cloning. This is a potentially promising result because other trials such as heat-shock, electroporation, and treatment with sepiolite for introducing DNA into the wild type S. mutans failed. Under defined conditions, the transformation efficiency of E. coli XL1-Blue and S. mutans exhibited ~2 × 10(5) and ~6 × 10(3)CFU/μg of plasmid DNA using magnesium-aminoclay. In contrast, transformation efficiency was higher in S. mutans than that in E. coli XL1-Blue for calcium-aminoclay. It was also confirmed that each plasmid transformed into E. coli and S. mutans was stably maintained and that they expressed the inserted gene encoding the green fluorescent protein during prolonged growth of up to 80 generations. © 2013.

  14. Calcium, copper, iron, magnesium, silicon and zinc content of hair in Parkinson's disease.

    Science.gov (United States)

    Forte, Giovanni; Alimonti, Alessandro; Violante, Nicola; Di Gregorio, Marco; Senofonte, Oreste; Petrucci, Francesco; Sancesario, Giuseppe; Bocca, Beatrice

    2005-01-01

    The aetiology of Parkinson's disease (PD) is still unknown, but some hypotheses have focused on the imbalances in body levels of metals as co-factors of risk. To assess whether hair could be a reliable marker of possible changes, calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), silicon (Si) and zinc (Zn) were determined in hair from 81 patients affected by PD and 17 age-matched controls. Care was taken to eliminate external contamination of the hair by thorough washing. Digestion of the matrix was achieved by an acid-assisted microwave procedure. Quantification of the elements was performed by inductively coupled plasma atomic emission spectrometry. Results indicated significantly lower levels of Fe in the hair of patients (p=0.018) compared with controls. Ca and Mg levels were slightly lower while Zn levels were higher in patients, although these differences were not significant; neither were variations in Cu and Si. Ca and Mg were at least 1.5 times higher in females than in males in both controls and patients. In addition, Ca correlated positively with Mg in both groups and in both sexes (p-value always less than 0.03), and negatively with age in patients (pParkinson treatment.

  15. Simultaneously detection of calcium and magnesium in various samples by calmagite and chemometrics data processing

    Science.gov (United States)

    Rasouli, Zolaikha; Ghavami, Raouf

    2016-12-01

    The current study describes results of the application of radial basis function-partial least squares (RBF-PLS), partial robust M-regression (PRM), singular value decomposition (SVD), evolving factor analysis (EFA), multivariate curve resolution with alternating least squares (MCR-ALS) and rank annihilation factor analysis (RAFA) methods for the purposes of simultaneous determination of trace amounts calcium (Ca2 +) and magnesium (Mg2 +) and exploratory analysis based on their colored complexes formation with 1-(1-hydroxy-4-methyl-2-phenylazo)-2-naphthol-4-sulfonic acid (calmagite) as chromomeric reagent. The complex formation Ca2 + and Mg2 + with calmagite was investigated under pH 10.20. The performance of RBF-PLS model in detection of minerals was compared with PRM as a linear model. The pure concentration and spectral profiles were obtained using MCR-ALS. EFA and SVD were used to distinguish the number species. The stability constants of the complexes were derived using RAFA. Finally, RBF-PLS was utilized for simultaneous determination of minerals in pharmaceutical formulation and various vegetable samples.

  16. Hydrogen production from steam reforming of acetic acid over Cu-Zn supported calcium aluminate.

    Science.gov (United States)

    Mohanty, Pravakar; Patel, Madhumita; Pant, Kamal K

    2012-11-01

    Hydrogen can be produced by catalytic steam reforming (CSR) of biomass-derived oil. Typically bio oil contains 12-14% acetic acid; therefore, this acid was chosen as model compound for reforming of biooil with the help of a Cu-Zn/Ca-Al catalyst for high yield of H(2) with low CH(4) and CO content. Calcium aluminate support was prepared by solid-solid reaction at 1350°C. X-ray diffraction indicates 12CaO·7Al(2)O(3) as major, CaA(l4)O(7) and Ca(5)A(l6)O(14) as minor phases. Cu and Zn were loaded onto the support by wet-impregnation at 10 and 1wt.%, respectively. The catalysts were characterized by Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy TEM and the surface area for both support and Cu-Zn were 10.5 and 5.8m(2)/g, respectively. CSR was carried out in a tubular fixed bed reactor (I.D.=19mm) at temperatures between 600 and 800°C with 3-g loadings and (H(2)O/acetic acid) wt. ratio of 9:1. Significantly high (80%) yield of hydrogen was obtained over Cu-Zn/Ca-Al catalyst, as incorporation of Zn enhanced the H(2) yield by reducing deactivation of the catalyst. The coke formation on the support (Ca-12/Al-7) surface was negligible due to the presence of excess oxygen in the 12CaO·7Al(2)O(3) phase. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Synthesis, characterization, and in-vitro cytocompatibility of amorphous β-tri-calcium magnesium phosphate ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Satish S., E-mail: sss42@pitt.edu [Department of Chemical & Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Roy, Abhijit, E-mail: abr20@pitt.edu [Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Lee, Boeun, E-mail: bol11@pitt.edu [Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Banerjee, Ipsita [Department of Chemical & Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Kumta, Prashant N., E-mail: pkumta@pitt.edu [Department of Chemical & Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Center for Craniofacial Regeneration, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Department of Mechanical Engineering and Materials Science, University of Pittsburgh, PA 15261 (United States)

    2016-10-01

    Biphasic mixtures of crystalline β-tricalcium magnesium phosphate (β-TCMP) and an amorphous calcium magnesium phosphate have been synthesized and reported to support enhanced hMSC differentiation in comparison to β-tricalcium phosphate (β-TCP) due to the release of increased amounts of bioactive ions. In the current study, completely amorphous β-TCMP has been synthesized which is capable of releasing increased amounts of Mg{sup 2+} and PO{sub 4}{sup 3−} ions, rather than a biphasic mixture as earlier reported. The amorphous phase formed was observed to crystallize between temperatures of 400–600 °C. The scaffolds prepared with amorphous β-TCMP were capable of supporting enhanced hMSC proliferation and differentiation in comparison to commercially available β-TCP. However, a similar gene expression of mature osteoblast markers, OCN and COL-1, in comparison to biphasic β-TCMP was observed. To further study the role of Mg{sup 2+} and PO{sub 4}{sup 3−} ions in regulating hMSC osteogenic differentiation, the capability of hMSCs to mineralize in growth media supplemented with Mg{sup 2+} and PO{sub 4}{sup 3−} ions was studied. Interestingly, 5 mM PO{sub 4}{sup 3−} supported mineralization while the addition of 5 mM Mg{sup 2+} to 5 mM PO{sub 4}{sup 3−} inhibited mineralization. It was therefore concluded that the release of Ca{sup 2+} ions from β-TCMP scaffolds also plays a role in regulating osteogenic differentiation on these scaffolds and it is noted that further work is required to more accurately determine the exact role of Mg{sup 2+} in regulating hMSC osteogenic differentiation. - Highlights: • Synthesis of amorphous Mg containing beta tricalcium phosphate ceramics • Amorphous beta TCMP supports enhanced hMSC proliferation and differentiation. • Amorphous beta TCMP shows comparable OCN and COL-1 expression to biphasic TCMP. • Presence of 5 mM Mg{sup 2+} and PO{sub 4}{sup 3−} ions in growth media inhibits hMSC mineralization.

  18. Properties of Calcium Acetate Manufactured with Etching Waste Solution and Limestone Sludge as a Cementitious High-Early-Strength Admixture

    Directory of Open Access Journals (Sweden)

    Deuck-Mo Kim

    2016-01-01

    Full Text Available Concrete is one of the most widely used construction materials. There are several methods available to improve its performance, with one of them being the use of high-early-strength admixtures (HESAs. Typical HESAs include calcium nitrate, calcium chloride, and calcium formate (CF. Industrial by-products, such as acetic acid and lime stone sludge (LSS, can be used together to produce calcium acetate (CA, which can subsequently be used as a cementitious HESA. In this study, calcium carbonate and LSS were mixed with cement in weight ratios of 1 : 1, 1 : 1.5, and 1 : 2, and the properties of the as-produced CA were evaluated. CA and CF were mixed with cement in different weight ratios (0, 1, 2, and 3 wt% to obtain CA- and CF-mortars, respectively. The flow behavior, setting time, pH, and compressive strength of these mortars were evaluated, and their X-ray diffraction patterns were also analyzed. It was found that as the CF content in the CF-mortar increased, the initial strength of the mortar also increased. However, it impaired its long-term strength. On the other hand, when 1% CA was mixed with cement, satisfactory early and long-term strengths were achieved. Thus, CA, which is obtained from industrial by-products, can be an effective HESA.

  19. Osteoblast-like cell responses to ion products released from magnesium- and silicate-containing calcium carbonates.

    Science.gov (United States)

    Yamada, Shinya; Ota, Yoshio; Obata, Akiko; Kasuga, Toshihiro

    2017-01-01

    Inorganic ions released from bioceramics and bioactive glasses have been reported to influence osteogenic cell functions. Cell responses depend on types of the ions provided, for example, silicate ion has been found to up-regulate their proliferation, differentiation and mineralization. Mouse osteoblast-like cells (MC3T3-E1) were cultured in media containing silicate and calcium ions with/without magnesium ion to evaluate their combined effects on the cell's functions. The cells were cultured in the media containing the extract of silicate-containing vaterite (SiV) and magnesium- and siloxane-containing one (MgSiV) and normal medium and then their adhesion, proliferation, differentiation and mineralization were evaluated. The adhesion of the cells was enhanced when they were cultured in the medium containing MgSiV-extract. Their proliferation and differentiation were up-regulated in both media containing MgSiV-extract and SiV-extract. In particular, the MgSiV-extract significantly enhanced their differentiation than the SiV-extract. This was supported by the mineralization test's results, which showed a large amount of mineral deposit was observed in the cells cultured in the MgSiV-extract medium. Providing the three kinds of ions was effective for up-regulating the cell's mineralization compared to providing silicate and calcium ions without magnesium ion.

  20. Use of magnesium as a drug in chronic kidney disease

    Science.gov (United States)

    Wilkie, Martin

    2012-01-01

    From chronic kidney disease (CKD) Stage 4 onwards, phosphate binders are needed in many patients to prevent the development of hyperphosphataemia, which can result in disturbed bone and mineral metabolism, cardiovascular disease and secondary hyperparathyroidism. In this review, we re-examine the use of magnesium-containing phosphate binders for patients with CKD, particularly as their use circumvents problems such as calcium loading, aluminum toxicity and the high costs associated with other agents of this class. The use of magnesium hydroxide in the 1980s has been superseded by magnesium carbonate, as the hydroxide salt was associated with poor gastrointestinal tolerability, whereas studies with magnesium carbonate show much better gastrointestinal profiles. The use of combined magnesium- and calcium-based phosphate binder regimens allows a reduction in the calcium load, and magnesium and calcium regimen comparisons show that magnesium may be as effective a phosphate binder as calcium. A large well-designed trial has recently shown that a drug combining calcium acetate and magnesium carbonate was non-inferior in terms of lowering serum phosphate to sevelamer-HCl and had an equally good tolerability profile. Because of the high cost of sevelamer and lanthanum carbonate, the use of magnesium carbonate could be advantageous and drug acquisition cost savings would compensate for the cost of introducing routine magnesium monitoring, if this is thought to be necessary and not performed anyway. Moreover, given the potential cost savings, it may be time to re-investigate magnesium-containing phosphate binders for CKD patients with further well-designed clinical research using vascular end points. PMID:26069822

  1. Carboxylated molecules regulate magnesium content of amorphous calcium carbonates during calcification.

    Science.gov (United States)

    Wang, Dongbo; Wallace, Adam F; De Yoreo, James J; Dove, Patricia M

    2009-12-22

    With the realization that many calcified skeletons form by processes involving a precursor phase of amorphous calcium carbonate (ACC), a new paradigm for mineralization is emerging. There is evidence the Mg content in biogenic ACC is regulated by carboxylated (acidic) proteins and other macromolecules, but the physical basis for such a process is unknown. We test the hypothesis that ACC compositions express a systematic relationship to the chemistry of carboxyl-rich biomolecules. A series of inorganic control experiments were conducted to establish the dependence of Mg/Ca ratios in ACC on solution composition. We then determined the influence of a suite of simple carboxylated organic acids on Mg content. Molecules with a strong affinity for binding Ca compared with Mg promote the formation of Mg-enriched ACC that is compositionally equivalent to high-magnesium calcites and dolomite. Measurements show Mg/Ca ratios are controlled by a predictable dependence upon the binding properties of the organic molecules. The trend appears rooted in the conformation and electrostatic potential topology of each molecule, but dynamic factors also may be involved. The dependence suggests a physical basis for reports that specific sequences of calcifying proteins are critical to modulating mineralization. Insights from this study may provide a plausible explanation for why some biogenic carbonates and carbonaceous cements often contain higher Mg signatures than those that are possible by classical crystal growth processes. The findings reiterate the controls of microenvironment on mineralization and suggest an origin of compositional offsets, or vital effects, long recognized by the paleoclimate community.

  2. Electron Solvation in Liquid Ammonia: Lithium, Sodium, Magnesium, and Calcium as Electron Sources.

    Science.gov (United States)

    Chaban, Vitaly V; Prezhdo, Oleg V

    2016-03-10

    A free electron in solution, known as a solvated electron, is the smallest possible anion. Alkali and alkaline earth atoms serve as electron donors in solvents that mediate outer-sphere electron transfer. We report herein ab initio molecular dynamics simulations of lithium, sodium, magnesium, and calcium in liquid ammonia at 250 K. By analyzing the electronic properties and the ionic and solvation structures and dynamics, we systematically characterize these metals as electron donors and ammonia molecules as electron acceptors. We show that the solvated metal strongly modifies the properties of its solvation shells and that the observed effect is metal-specific. Specifically, the radius and charge exhibit major impacts. The single solvated electron present in the alkali metal systems is distributed more uniformly among the solvent molecules of each metal's two solvation shells. In contrast, alkaline earth metals favor a less uniform distribution of the electron density. Alkali and alkaline earth atoms are coordinated by four and six NH3 molecules, respectively. The smaller atoms, Li and Mg, are stronger electron donors than Na and Ca. This result is surprising, as smaller atoms in a column of the periodic table have higher ionization potentials. However, it can be explained by stronger electron donor-acceptor interactions between the smaller atoms and the solvent molecules. The structure of the first solvation shell is sharpest for Mg, which has a large charge and a small radius. Solvation is weakest for Na, which has a small charge and a large radius. Weak solvation leads to rapid dynamics, as reflected in the diffusion coefficients of NH3 molecules of the first two solvation shells and the Na atom. The properties of the solvated electrons established in the present study are important for radiation chemistry, synthetic chemistry, condensed-matter charge transfer, and energy sources.

  3. Effect of diuretics on renal tubular transport of calcium and magnesium.

    Science.gov (United States)

    Alexander, R Todd; Dimke, Henrik

    2017-06-01

    Calcium (Ca 2+ ) and Magnesium (Mg 2+ ) reabsorption along the renal tubule is dependent on distinct trans- and paracellular pathways. Our understanding of the molecular machinery involved is increasing. Ca 2+ and Mg 2+ reclamation in kidney is dependent on a diverse array of proteins, which are important for both forming divalent cation-permeable pores and channels, but also for generating the necessary driving forces for Ca 2+ and Mg 2+ transport. Alterations in these molecular constituents can have profound effects on tubular Ca 2+ and Mg 2+ handling. Diuretics are used to treat a large range of clinical conditions, but most commonly for the management of blood pressure and fluid balance. The pharmacological targets of diuretics generally directly facilitate sodium (Na + ) transport, but also indirectly affect renal Ca 2+ and Mg 2+ handling, i.e., by establishing a prerequisite electrochemical gradient. It is therefore not surprising that substantial alterations in divalent cation handling can be observed following diuretic treatment. The effects of diuretics on renal Ca 2+ and Mg 2+ handling are reviewed in the context of the present understanding of basal molecular mechanisms of Ca 2+ and Mg 2+ transport. Acetazolamide, osmotic diuretics, Na + /H + exchanger (NHE3) inhibitors, and antidiabetic Na + /glucose cotransporter type 2 (SGLT) blocking compounds, target the proximal tubule, where paracellular Ca 2+ transport predominates. Loop diuretics and renal outer medullary K + (ROMK) inhibitors block thick ascending limb transport, a segment with significant paracellular Ca 2+ and Mg 2+ transport. Thiazides target the distal convoluted tubule; however, their effect on divalent cation transport is not limited to that segment. Finally, potassium-sparing diuretics, which inhibit electrogenic Na + transport at distal sites, can also affect divalent cation transport. Copyright © 2017 the American Physiological Society.

  4. Potassium, calcium, magnesium, and sodium levels in biological samples of hypertensive and nonhypertensive diabetes mellitus patients.

    Science.gov (United States)

    Afridi, Hassan Imran; Kazi, Tasneem Gul; Kazi, Naveed; Jamali, Mohammad Khan; Arain, Mohammad Bilal; Jalbani, Nusrst; Sarfaraz, Raja Adil; Shah, Afzal; Kandhro, Ghulam Abbas; Shah, Abdul Qadir; Baig, Jameel Ahmed

    2008-09-01

    There is accumulating evidence that the metabolism of several essential elements is altered in diabetes mellitus and that these nutrients might have specific roles in the pathogenesis and progress of this disease. The aim of the present study was to compare the level of essential elements, potassium (K), calcium (Ca), magnesium (Mg), and sodium (Na), in biological samples (whole blood, urine, and scalp hair) of patients who have hypertensive diabetes mellitus type 2 (n = 254) and nonhypertensive diabetes mellitus type 2 (n = 228) with those of nondiabetic as control subjects (n = 182; age range of both genders 45-75). The element concentrations were measured by means of an atomic absorption spectrophotometer after microwave-induced acid digestion. The validity and accuracy was checked by conventional wet acid digestion method and using certified reference materials. The overall recoveries of all elements were found in the range of 99.1-99.9% of certified values. The results of this study showed that the mean values of K, Mg, and Ca were significantly reduced, while Na level were higher in blood and scalp hair samples of hypertensive diabetic (HD) patients and nonhypertensive diabetic (NHD) patients as compared to control subjects of both genders (p diabetic patient was found to be higher, but it was not significant (p = 0.05).The urinary levels of these elements were found to be higher in both HD and NHD patients than in the age-matched healthy controls. These results are consistent with those obtained in other studies, confirming that deficiency and efficiency of some essential trace metals may play a role in the development of diabetes mellitus.

  5. [Characteristics of accumulation and distribution of nitrogen, phosphorus, potassium, calcium and magnesium in Chrysanthemum morifolium].

    Science.gov (United States)

    Liu, Dahui; Guo, Lanping; Zhu, Duanwei; Liu, Wei; Jin, Hang

    2009-10-01

    To study the characteristics of dry matter accumulation and N, P, K, Ca and Mg accumulation and distribution of Chrysanthemum morifolium. The sampling were carried out on the different growing time of C. morifolium, and the amount of dry matter and the content of N, P, K, Ca and Mg in all parts of the plant were measured. The dry matter accumulation was lineally increased with the absorption and accumulation of N, P, K, Ca, and Mg. In different growing periods, the accumulation and distribution of mineral nutrition were different in C. morifolium. The mineral nutrition was mostly in the leaf of the plant in the vegetative period. When the growth changed from vegetative growth to reproductive growth, the mineral nutrition was transferred and distributed into bud, flower and root shoot. And the period of flower bud differentiation of C. morifolium was the period of maximal accumulation of dry matter and showed the maximum efficiency of N, P and K nutrition. For production of 100 kg dry flower 4.13 kg N, 0.37 kg P, 5.03 kg K, 3.03 kg Ca and 0.81 kg Mg were needed. And the ratio of them was 1:0.09:1.22:0.73:0.20. The period of flower bud differentiation is the most crucial period in the growth of C. morifolium. And it must pay attention to the supply of mineral nutrition and moisture of plant to promote flower formation and dry matter accumulation in this period. It is strongly recommended that the phosphorus and potassium fertilizers should be early applied, the nitrogenous fertilizer should be applied dividedly, and the calcium magnesium fertilizers are also applied properly.

  6. Blood Magnesium, and the Interaction with Calcium, on the Risk of High-Grade Prostate Cancer

    Science.gov (United States)

    Motley, Saundra S.; Smith, Joseph A.; Concepcion, Raoul; Barocas, Daniel; Byerly, Susan

    2011-01-01

    Background Ionized calcium (Ca) and magnesium (Mg) compete as essential messengers to regulate cell proliferation and inflammation. We hypothesized that inadequate Mg levels, perhaps relative to Ca levels (e.g. a high Ca/Mg ratio) are associated with greater prostate cancer risk. Study Design In this biomarker sub-study of the Nashville Men's Health Study (NMHS), we included 494 NMHS participants, consisting of 98 high-grade (Gleason≥7) and 100 low-grade cancer cases, 133 prostate intraepithelial neoplasia (PIN) cases, and 163 controls without cancer or PIN at biopsy. Linear and logistic regression were used to determine associations between blood Ca, Mg, and the Ca/Mg ratio across controls and case groups while adjusting for potential confounding factors. Results Serum Mg levels were significantly lower, while the Ca/Mg ratio was significantly higher, among high-grade cases vs. controls (p = 0.04, p = 0.01, respectively). Elevated Mg was significantly associated with a lower risk of high-grade prostate cancer (OR = 0.26 (0.09, 0.85)). An elevated Ca/Mg ratio was also associated with an increased risk of high-grade prostate cancer (OR = 2.81 (1.24, 6.36) adjusted for serum Ca and Mg). In contrast, blood Ca levels were not significantly associated with prostate cancer or PIN.Mg, Ca, or Ca/Mg levels were not associated with low-grade cancer, PIN, PSA levels, prostate volume, or BPH treatment. Conclusion Low blood Mg levels and a high Ca/Mg ratio were significantly associated with high-grade prostate cancer. These findings suggest Mg affects prostate cancer risk perhaps through interacting with Ca. PMID:21541018

  7. Lime and calcium-magnesium silicate in the ionic speciation of an Oxisol

    Directory of Open Access Journals (Sweden)

    João Arthur Antonangelo

    Full Text Available ABSTRACT Plant residues and certain fertilizers accelerate soil acidification and increase the levels of aluminum-Al+3 in soils under no-tillage (NT. Silicates act as acidity amendments and as a source of silicon as in H4SiO4. An increase in the pH of soil solution causes the deprotonation of H4SiO4 and generates the anionic form (H3SiO4−. The aim of this study was to evaluate the ionic speciation of Si, Al, Ca, Mg and K in aqueous extracts by means of a software calculation. Since 2006, a field experiment has been under way on an Oxisol under NT subjected to lime and calcium-magnesium silicate applications under four crop systems. The amendments were applied in Oct 2006 and in Oct 2011, aiming to raise base saturation to 70 %. Soil samples were collected in Oct 2013, at depths of 0-5, 5-10, 10-20, 20-40 and 40-60 cm. Both Ca and Mg formed complexes with dissolved organic carbon (DOC whereas the same was not observed for potassium. These three basic cations were mostly in their free forms regardless of treatment, while Al was mostly complexed with DOC even at the lowest depths (40-60 cm. The highest value of free Al form was 15 %. Si was almost 100 % as H4SiO4, and its activity was similar to its concentration in solution for all crop systems and at all depths, regardless of amendment applied. The percentages of H3SiO4− and Al-H3SiO42+ were irrelevant, providing more phytoavailable H4SiO4 in soil solution.

  8. Neutron and X-ray diffraction and empirical potential structure refinement modelling of magnesium stabilised amorphous calcium carbonate

    DEFF Research Database (Denmark)

    Cobourne, G.; Mountjoy, G.; Rodriguez Blanco, Juan Diego

    2014-01-01

    Amorphous calcium carbonate (ACC) plays a key role in biomineralisation processes in sea organisms. Neutron and X-ray diffraction have been performed for a sample of magnesium-stabilised ACC, which was prepared with a Mg:Ca ratio of 0.05:1 and 0.25 H2O molecules per molecule of CO3. The empirical...... potential structure refinement method has been used to make a model of magnesium-stabilised ACC and the results revealed a fair agreement with the experimental diffraction data. The model has well-defined CO3 and H2O molecules. The average coordination number of Ca is 7.4 and is composed of 6.8 oxygen atoms...

  9. Photo-luminescent properties of a green or red emitting Tb3+ or Eu3+ doped calcium magnesium silicate phosphors

    Science.gov (United States)

    Onani, Martin O.; Dejene, Francis B.

    2014-04-01

    This study describes green-emitting Tb3+ or red-emitting Eu3+ doped calcium magnesium silicate phosphors by ultraviolet excitation at 335 nm. The rare earth activated amorphous calcium silicate was prepared by a solution-combustion process at 600 °C for 5-10 min. The Ca2MgSi2O7 prepared using urea and ammonium nitrate has a tetragonal crystal structure. The resulting Tb3+-doped phosphor emitted green light centered at 544 nm. The optimum excitation wavelength within the range 300-400 nm was 335 nm. The intensity and emitting wavelength of the Eu3+ doped samples can be controlled by annealing in a reducing or oxidizing environment, allowing light to be emitted as green or red. When the reducing environment is optimized, the emission spectrum of Ca2MgSi2O7:Eu2+ is a broad band at 497 nm.

  10. Magnesium/calcium related neurological disorders in the ALS focus of the Kii Peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Yasui, Masayuki; Yoshida, Munehito; Tamaki, Tetsuya; Taniguchi, Yasunori; Minamide, Akihito; Ota, Kiichiro [Wakayama Medical Coll. (Japan); Sasajima, Kazuhisa

    1997-01-01

    Current epidemiological surveys in the Western Pacific area and Kii Peninsula have suggested that low calcium(Ca), magnesium(Mg) and high aluminum(Al) and manganese(Mn) in river, soil and drinking water may be implicated in the pathogenetic process of amyotrophic lateral sclerosis(ALS) and Parkinsonism-dementia(PD). The condition of unbalanced minerals was experimentally mimicked in this study using rats. Male Wistar rats, weighing 200 g, were maintained for 90 days on the following diets: (A) standard diet, (B) low Ca diet, (C) low Ca-Mg diet, (D) low Ca-Mg diet with high Al. In the groups maintained on unbalanced mineral diets, Ca and Mg contents of the bones were lower than standard diet. On the other hand, Ca content of CNS showed higher values in the unbalanced diet groups than those in the standard diet group. This was determined by neutron activation analysis(NAA) at KUR. Also, Ca content in soft tissues of rats given unbalanced mineral diets was higher than those on standard diet. Mg content of soft tissues and spinal cord of rats was markedly lower in the low Ca-Mg plus high Al diet group than the other three groups as determined by inductively coupled plasma emission spectrometry(ICP). Six Kii cases with amyotrophic lateral sclerosis(ALS) also showed higher Ca and lower Mg contents in the CNS tissues than those of neurologically normal controls. The calcification of the spinal ligaments(CSL) has been reported in only 120 cases in the world and 28 cases of CSL in the Kii Peninsula have been found in the same foci as ALS. We analyzed Mg content of 7 spinal bones and 10 ligaments of the CSL and Ca content of 5 spinal bones compared with controls. The CSL showed lower values of Mg contents in bones and ligaments compared to controls. The Ca content in bones of CSL was significantly lower than that of controls. This suggests that the environmental factor may contribute to the pathogenesis of CSL due to low Ca and Mg intake as well as for ALS. (J.P.N.)

  11. The effect of gestation and lactation on bone calcium, phosphorus and magnesium in dairy cows

    Directory of Open Access Journals (Sweden)

    D.E. Beighle

    1999-07-01

    Full Text Available A study was conducted to monitor changes in cortical bone mineral in the dairy cow in response to demands of lactation and pregnancy using rib bone biopsies in serial sampling. Sixteen Friesian cows from the University dairy herd were used to collect 9 samples during the lactation period and 5 samples during the dry period. The data were analysed using a split-plot design analysis of variance. There were no significant (P > 0.05 differences in cortical bone phosphorus concentrations in rib bone during the lactation period, but calcium concentrations in cortical bone were significantly (P < 0.05 higher at parturition and during the first 30 days of lactation compared to the next 30 days and between 90 and 120 days. Results reported here indicate that the cow resorbs cortical bone during the middle of the lactation period and not during the periparturient period as previously thought. Magnesium concentrations were also significantly (P < 0.05 higher at the beginning of lactation compared to some of the other sampling times, but cortical bone was significantly (P < 0.05 thinner at the beginning of lactation compared to several of the other sampling times. There were no significant (P > 0.05 differences in cortical bone Ca or Mg concentrations during the gestation period. Cortical bone P concentrations significantly (P < 0.05 decreased during the first 180 days, but significantly (P < 0.05 increased at 181-230 days and significantly (P < 0.05 decreased again at 231 days to term. Cortical bone thickness decreased significantly (P < 0.05 from the beginning of gestation to term. There were no significant (P > 0.05 differences in cortical bone thickness or Ca or Mg concentrations in cortical bone during the dry period, but cortical bone P concentrations were significantly (P < 0.05 greater at the end of the dry period compared to the first 30 days of the period. In general, cortical bone Ca and Mg values decreased as milk production increased up to 20

  12. Luminescence properties of dysprosium doped calcium magnesium silicate phosphor by solid state reaction method

    Energy Technology Data Exchange (ETDEWEB)

    Sahu, Ishwar Prasad, E-mail: ishwarprasad1986@gmail.com [School of Studies in Physics & Astrophysics, Pt. Ravishankar Shukla University, Raipur, C.G. 492010 (India); Chandrakar, Priya; Baghel, R.N.; Bisen, D.P.; Brahme, Nameeta [School of Studies in Physics & Astrophysics, Pt. Ravishankar Shukla University, Raipur, C.G. 492010 (India); Tamrakar, Raunak Kumar [Department of Applied Physics, Bhilai Institute of Technology, Durg, C.G. 491001 (India)

    2015-11-15

    Dysprosium doped calcium magnesium silicate (CaMgSi{sub 2}O{sub 6}:Dy{sup 3+}) white light emitting phosphor was synthesized by solid state reaction process. The crystal structure of sintered phosphor was monoclinic structure with space group C2/c. Chemical composition of the sintered CaMgSi{sub 2}O{sub 6}:Dy{sup 3+} phosphor was confirmed by EDX. The prepared CaMgSi{sub 2}O{sub 6}:Dy{sup 3+} phosphor was excited from 352 nm and their corresponding emission spectra were recorded at blue (470 nm), yellow (570 nm) and red (675 nm) line due to the {sup 4}F{sub 9/2} → {sup 6}H{sub 15/2}, {sup 4}F{sub 9/2} → {sup 6}H{sub 13/2}, {sup 4}F{sub 9/2} → {sup 6}H{sub 11/2} transitions of Dy{sup 3+} ions. The combination of these three emissions constituted as white light confirmed by the Commission Internationale de L'Eclairage (CIE) chromatic coordinate diagram. The possible mechanism of the white light emitting long lasting CaMgSi{sub 2}O{sub 6}:Dy{sup 3+} phosphor was also investigated. Investigation on afterglow property show that phosphor held fast and slow decay process. The peak of mechanoluminescence (ML) intensity increases linearly with increasing impact velocity of the moving piston. Thus the present investigation indicates that the local piezoelectricity-induced electron bombardment model is responsible to produce ML in prepared CaMgSi{sub 2}O{sub 6}:Dy{sup 3+} phosphor. - Highlights: • The crystal structure of CaMgSi{sub 2}O{sub 6}:Dy{sup 3+} phosphor is consistent with standard monoclinic structure. • CIE coordinates of CaMgSi{sub 2}O{sub 6}:Dy{sup 3+} phosphor is suitable as white light emitting phosphor. • The local piezoelectricity-induced electron bombardment model is responsible to produce ML in CaMgSi{sub 2}O{sub 6}:Dy{sup 3+} phosphor.

  13. EFFECT OF LIMING AND USE OF WASTE ORGANIC MATERIALS ON THE CONTENTS OF CALCIUM AND MAGNESIUM IN COCK’S-FOOT CULTIVATED ON NICKEL-CONTAMINATED SOIL

    Directory of Open Access Journals (Sweden)

    Beata Kuziemska

    2016-05-01

    Full Text Available The effect of liming and the addition to soil of waste organic materials on the contents of calcium and magnesium in cock’s-foot (Dactylis glomerata L. cultivated on soil contaminated to various degrees with nickel was studied in a pot culture experiment. Plants from four cuts of grass were analysed in the third year of the study. The following factors were taken into account: 1 – contamination of soils with nickel (0, 75, 150 and 225 mg N·kg-1 of soil; 2 – liming (0 Ca and Ca according to Hh of soil; 3 – waste organic materials (no waste organic materials added, brown coal and rye straw. With increasing nickel content in soil, the magnesium content in biomass of the test plant decreased. The applied liming resulted in an increase in the average calcium content and a decrease in the magnesium content in cock’s-foot. No significant effect of introducing straw to soil on the contents of calcium and magnesium in biomass of the grass was found, while the effect of brown coal was visible both for calcium and for magnesium (in the plants harvested from the objects to which brown coal was applied, the contents of both macroelements were, on average, lower than in the plants harvested from the control objects.

  14. Relative influences of solution composition and presence of intracrystalline proteins on magnesium incorporation in calcium carbonate minerals: Insight into vital effects

    Science.gov (United States)

    Hermans, Julie; André, Luc; Navez, Jacques; Pernet, Philippe; Dubois, Philippe

    2011-03-01

    Biogenic calcites may contain considerable magnesium concentrations, significantly higher than those observed in inorganic calcites. Control of ion concentrations in the calcifying space by transport systems and properties of the organic matrix of mineralization are probably involved in the incorporation of high magnesium quantities in biogenic calcites, but their relative effects have never been quantified. In vitro precipitation experiments performed at different Mg/Ca ratios in the solution and in the presence of soluble organic matrix macromolecules (SOM) extracted from sea urchin tests and spines showed that, at a constant temperature, magnesium incorporation in the precipitated minerals was mainly dependent on the Mg/Ca ratio of the solution. However, a significant increase in magnesium incorporation was observed in the presence of SOM compared with control experiments. Furthermore, this effect was more pronounced with SOM extracted from the test, which was richer in magnesium than the spines. According to SEM observations, amorphous calcium carbonate was precipitated at high Mg/Casolution. The observed predominant effect of Mg/Casolution, probably mediated in vivo by ion transport to and from the calcifying space, was suggested to induce and stabilize a transient magnesium-rich amorphous phase essential to the formation of high magnesium calcites. Aspartic acid rich proteins, shown to be more abundant in the test than in the spine matrix, further stabilize this amorphous phase. The involvement of the organic matrix in this process can explain the observation that sympatric organisms or even different skeletal elements of the same individual present different skeletal magnesium concentrations.

  15. Time bound changes (in 24 h in human sperm motility and level of calcium and magnesium in seminal plasma

    Directory of Open Access Journals (Sweden)

    J. Valsa

    2016-09-01

    Level of calcium (27.2 mg/dl and magnesium (13.54 mg/dl in seminal plasma did not show any significant changes during study period from that of at ½ h. The study concluded that electrolytes under study were not responsible for the decrease in motility during study period.

  16. Relationship between tap water hardness, magnesium, and calcium concentration and mortality due to ischemic heart disease or stroke in the Netherlands

    NARCIS (Netherlands)

    Leurs, L.J.; Schouten, L.J.; Mons, M.N.; Goldbohm, R.A.; Brandt, P.A. van den

    2010-01-01

    BACKGROUND: Conflicting results on the relationship between the hardness of drinking water and mortality related to ischemic heart disease (IHD) or stroke have been reported. OBJECTIVES: We investigated the possible association between tap water calcium or magnesium concentration and total hardness

  17. Een vergelijkend onderzoek tussen vlam-AAS en ICP-AES voor de bepaling van calcium, magnesium en natrium in drinkwater

    NARCIS (Netherlands)

    Boer; J.L.M.de; Martens; W.M.

    1985-01-01

    Vanwege de wenselijkheid in verband met een aanzienlijke tijdsbesparing van de overgang van de bepaling van calcium, magnesium en natrium in drinkwater met behulp van een vlam-AAS procedure op een ICP-AES procedure werd een vergelijkend onderzoek voor deze twee technieken uitgevoerd. Daartoe

  18. Plasma and erythrocyte magnesium, manganese, zinc, and plasma calcium levels in G-6-PD-deficient and normal male children.

    Science.gov (United States)

    Sarikcioglu, Süreyya Bilmen; Gümüslü, Saadet; Uysal, Nimet; Aksu, T Aslan

    2004-01-01

    Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is the most common human enzymopathy in the world. Trace elements are important for normal hematopoiesis and can play a role in acute hemolytic anemia induced by G-6-PD deficiency. For this purpose, we studied two groups consisting of 10 male children who are G-6-PD-deficient and 12 age-matched normal male children to compare plasma and erythrocyte magnesium, manganese, zinc, and plasma calcium levels between G-6-PD-deficient and normal children. All assays were performed under normal conditions free of any oxidative attack that may result in hemolytic crisis in G-6-PD-deficient subjects. All parameters in each group did not differ significantly except for erythrocyte G-6-PD activities. These data show that plasma and erythrocyte trace element contents of G-6-PD-deficient subjects do not differ in normal conditions.

  19. Preparation and characterization of bioactive and degradable composites containing ordered mesoporous calcium-magnesium silicate and poly(L-lactide)

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Jiajin [Key Shanghai Key Laboratory of Advanced Polymeric Materials, East China University of Science and Technology, Shanghai 200237 (China); Dong, Xieping, E-mail: jxzhyxh@163.com [Department of Orthopaedic Surgery, Jiangxi People' s Hospital, Nanchang 330006 (China); Ma, Xuhui [Polymer Science (Shenzhen) New Materials Co., Ltd., Shenzhen 518101 (China); Tang, Songchao, E-mail: schtang@ecust.edu.cn [Key Shanghai Key Laboratory of Advanced Polymeric Materials, East China University of Science and Technology, Shanghai 200237 (China); Wu, Zhaoying; Xia, Ji; Wang, Quanxiang; Wang, Yutao; Wei, Jie [Key Shanghai Key Laboratory of Advanced Polymeric Materials, East China University of Science and Technology, Shanghai 200237 (China)

    2014-10-30

    Highlights: • Mesoporous calcium-magnesium silicate and poly(L-lactide) composite was fabricated. • The composite has good hydrophilicity, in vitro degradation and bioactivity. • The composite could support cell attachment, proliferation and differentiation. - Abstract: Polylactide (PLA) and its copolymers have been widely used for bone tissue regeneration. In this study, a bioactive composite of ordered mesoporous calcium–magnesium silicate (m-CMS) and poly(L-lactide) (PLLA) was fabricated by melt blending method. The results indicated that the m-CMS particles were entrapped by polymer phase, and crystallinity of PLLA significantly decreased while the thermal stability of the m-CMS/PLLA composites was not obviously affected by addition of the m-CMS into PLLA. In addition, compared to PLLA, incorporation of the m-CMS into PLLA significantly improved the hydrophilicity, in vitro degradability and bioactivity (apatite-formation ability) of the m-CMS/PLLA composite, which were m-CMS content dependent. Moreover, it was found that incorporation of the m-CMS into PLLA could neutralize the acidic degradation by-products and thus compensated for the decrease of pH value. In cell culture experiments, the results showed that the composite enhanced attachment, proliferation and alkaline phosphatase activity (ALP) of MC3T3-E1 cells, which were m-CMS content dependent. The results indicated that the addition of bioactive materials to PLLA could result in a composite with improved properties of hydrophilicity, degradability, bioactivity and cytocompatibility.

  20. Concentration changeability of phosphorus, calcium and magnesium in selected partial drainage basins of the River Drwęca

    Directory of Open Access Journals (Sweden)

    Pius Bożena

    2015-12-01

    Full Text Available The paper presents the results of the research conducted between November 2008 and October 2009. The research included seasonal dynamics of the flow and runoff of phosphorus compounds (TP and P-PO43-, as well as Ca2+ and Mg2+ from 13 partial drainage basins of the River Drwęca. Water levels were registered automatically every day by recorders, and measurements of the flow were conducted once a month. Major differences were found in the water abundance as indicated by specific discharges in individual, partial drainage basins: from 1.87 dm3 s-1 km-2 (Lubianka - a lower part of the River Drwęca drainage basin to 8.22 dm3 s-1 km-2 (Gizela - an upper part of the River Drwęca drainage basin. The studied rivers were characterised by very diverse average content of total phosphorus compounds: from 0.047 mg dm-3 (Iłga to 0.816 mg dm-3 (Sandela; calcium: from 47.18 mg dm-3 (Iłga to 131.65 mg dm-3 (Trynka; and magnesium: from 9.71 mg dm-3 (Wel to 36.76 mg dm-3 (Struga Rychnowska. Analysis of variance carried out on hydrochemical properties of the studied rivers divides the rivers into two separate groups: rivers with much higher content of phosphorus, calcium and magnesium compounds (Struga Rychnowska, Trynka, Ruziec, Lubianka, Kujawka, Sandela and Gizela, and a group of rivers with low content of these compounds (Brynica, Brodniczanka, Skarlanka, Wel, Iłga.

  1. Hierarchical porous carbon derived from Allium cepa for supercapacitors through direct carbonization method with the assist of calcium acetate

    KAUST Repository

    Xu, Jinhui

    2017-11-02

    In this paper, a direction carbonization method was used to prepare porous carbon from Allium cepa for supercapacitor applications. In this method, calcium acetate was used to assist carbonization process. Scanning electron microscope (SEM) and N2 adsorption/desorption method were used to characterize the morphology, Brunauer-Emmett-Teller (BET) specific surface area and pore size distribution of porous carbon derived from Allium cepa (onion derived porous carbon, OPC). OPC is of hierarchical porous structure with high specific surface area and relatively high specific capacitance. OPC possesses relatively high specific surface area of 533.5 m2/g. What’s more, OPC possesses a specific capacitance of 133.5 F/g at scan rate of 5 mV/s.

  2. A randomized, double-blind, placebo-controlled trial of calcium acetate on serum phosphorus concentrations in patients with advanced non-dialysis-dependent chronic kidney disease

    Directory of Open Access Journals (Sweden)

    Ho Chiang-Hong

    2011-02-01

    Full Text Available Abstract Background Hyperphosphatemia in patients with chronic kidney disease (CKD contributes to secondary hyperparathyroidism, soft tissue calcification, and increased mortality risk. This trial was conducted to examine the efficacy and safety of calcium acetate in controlling serum phosphorus in pre-dialysis patients with CKD. Methods In this randomized, double-blind, placebo-controlled trial, 110 nondialyzed patients from 34 sites with estimated GFR 2 and serum phosphorus > 4.5 mg/dL were randomized to calcium acetate or placebo for 12 weeks. The dose of study drugs was titrated to achieve target serum phosphorus of 2.7-4.5 mg/dL. Serum phosphorus, calcium, iPTH, bicarbonate and serum albumin were measured at baseline and every 2 weeks for the 12 week study period. The primary efficacy endpoint was serum phosphorus at 12 weeks. Secondary endpoints were to measure serum calcium and intact parathyroid hormone (iPTH levels. Results At 12 weeks, serum phosphorus concentration was significantly lower in the calcium acetate group compared to the placebo group (4.4 ± 1.2 mg/dL vs. 5.1 ± 1.4 mg/dL; p = 0.04. The albumin-adjusted serum calcium concentration was significantly higher (9.5 ± 0.8 vs. 8.8 ± 0.8; p p Conclusions In CKD patients not yet on dialysis, calcium acetate was effective in reducing serum phosphorus and iPTH over a 12 week period. Trial Registration www.clinicaltrials.gov NCT00211978.

  3. Final report of the safety assessment of L-Ascorbic Acid, Calcium Ascorbate, Magnesium Ascorbate, Magnesium Ascorbyl Phosphate, Sodium Ascorbate, and Sodium Ascorbyl Phosphate as used in cosmetics.

    Science.gov (United States)

    Elmore, Amy R

    2005-01-01

    L-Ascorbic Acid, Calcium Ascorbate, Magnesium Ascorbate, Magnesium Ascorbyl Phosphate, Sodium Ascorbate, and Sodium Ascorbyl Phosphate function in cosmetic formulations primarily as antioxidants. Ascorbic Acid is commonly called Vitamin C. Ascorbic Acid is used as an antioxidant and pH adjuster in a large variety of cosmetic formulations, over 3/4 of which were hair dyes and colors at concentrations between 0.3% and 0.6%. For other uses, the reported concentrations were either very low (Ascorbate and Magnesium Ascorbate are described as antioxidants and skin conditioning agents--miscellaneous for use in cosmetics, but are not currently used. Sodium Ascorbyl Phosphate functions as an antioxidant in cosmetic products and is used at concentrations ranging from 0.01% to 3%. Magnesium Ascorbyl Phosphate functions as an antioxidant in cosmetics and was reported being used at concentrations from 0.001% to 3%. Sodium Ascorbate also functions as an antioxidant in cosmetics at concentrations from 0.0003% to 0.3%. Related ingredients (Ascorbyl Palmitate, Ascorbyl Dipalmitate, Ascorbyl Stearate, Erythorbic Acid, and Sodium Erythorbate) have been previously reviewed by the Cosmetic Ingredient Review (CIR) Expert Panel and found "to be safe for use as cosmetic ingredients in the present practices of good use." Ascorbic Acid is a generally recognized as safe (GRAS) substance for use as a chemical preservative in foods and as a nutrient and/or dietary supplement. Calcium Ascorbate and Sodium Ascorbate are listed as GRAS substances for use as chemical preservatives. L-Ascorbic Acid is readily and reversibly oxidized to L-dehydroascorbic acid and both forms exist in equilibrium in the body. Permeation rates of Ascorbic Acid through whole and stripped mouse skin were 3.43 +/- 0.74 microg/cm(2)/h and 33.2 +/- 5.2 microg/cm(2)/h. Acute oral and parenteral studies in mice, rats, rabbits, guinea pigs, dogs, and cats demonstrated little toxicity. Ascorbic Acid and Sodium Ascorbate acted

  4. Relationship between magnesium extracted by 0.01 M calcium chloride extraction procedure and conventional procedures

    NARCIS (Netherlands)

    Erp, van P.J.; Houba, V.J.G.; Reijneveld, J.A.; Beusichem, van M.L.

    2001-01-01

    A multinutrient soil extraction procedure in routine soil testing is attractive. Therefore, it has been suggested to convert conventional soil testing programs into a 0.01 M calcium chloride (CaCl2) multinutrient soil testing program using the relationship between test values of the 0.01 M CaCl2

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

    Science.gov (United States)

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

    1992-01-01

    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.

  6. Immunodeficiency after allogeneic bone marrow transplantation in man. Effect of phorbol ester (phorbol myristate acetate) and calcium ionophore (A23187) in vitro

    DEFF Research Database (Denmark)

    Møller, J; Hofmann, B; Langhoff, E

    1989-01-01

    that the proliferative response of patient cells was reduced both when the cells were stimulated with phytohaemagglutinin (PHA) and when they were stimulated with a combination of phorbol myristate acetate (PMA), which is an activator of protein kinase C (PKC), and the calcium ionophore A23187, which irreversibly opens...

  7. [Chemical analysis of the integument and digestive gland of Crangon crangon (Linné) (Crustacea, Decapoda) by x ray spectography. Quantitative variations in the elements of calcium, phosphorus, sulfur, and magnesium during the intermolt cycle].

    Science.gov (United States)

    Chassard-Bouchaud, C

    1977-03-14

    Electron probe microanalysis is a very suitable method for qualitative and quantitative analysis of calcium, phosphorus, sulfur and magnesium occurring within integument and digestive gland; variations related to intermolt cycle can be compared.

  8. CALCIUM AND MAGNESIUM CATIONS INFLUENCE ON ANTIMICROBIAL AND ANTIADHESIVE ACTIVITY OF ACINETOBACTER CALCOACETICUS ІMV B-7241 SURFACTANTS

    Directory of Open Access Journals (Sweden)

    P. Pirog

    2016-12-01

    Full Text Available The aim of the work was to study the effect of calcium and magnesium cations on NADP+-dependent glutamate dehydrogenase activity (key enzyme of biosynthesis of Acinetobacter calcoaceticus ІMV B-7241 surface-active aminolipids followed by modification of medium composition and determining antimicrobial and antiadhesive activity of synthesized surfactants. The strain IMV B-7241 was grown in medium with ethanol. NADP+-dependent glutamate dehydrogenase activity of the cell-free extract was analyzed using the formation of glutamate in the oxidation of NADPH. Surfactants were extracted from supernatant of cultural liquid by mixture of chloroform and methanol (2:1. Antimicrobial against bacteria properties of the surfactants were determined by index of the minimal inhibitory concentration. The number of attached cells and the degree of biofilm destruction were analyzed spectrophotometrically. It was established that in the presence of 10 mM Cа2+ and Mg2 NADP+-dependent glutamate dehydrogenase activity in the cell-free extract increased to 1.5 times in comparison with that without cations. Increasing concentration of magnesium sulfate to 0.2 g/l, or adding CaCl2 (0.1 g/l into cultivation medium of IMV B-7241 strain was accompanied by rise of NADP+-dependent glutamate dehydrogenase activity in 2.4 and 3.0 times respectively, as well as increasing antimicrobial and antiadhesive activity of synthesized surfactants. Minimal inhibitory concentration of surfactants synthesized in modified media against some bacteria was in 1.3−3.5 times, adhesion on abiotic surfaces treated with such surfactants in an average of 7−13% lower, and the degree of biofilm destruction in 7−13% higher as compared to indicators for the surfactant produced in the base medium. The obtained results indicated the possibility of regulating antimicrobial and anti-adhesive activity of surfactants under producer cultivation.

  9. Hypochlorhydria from short-term omeprazole treatment does not inhibit intestinal absorption of calcium, phosphorus, magnesium or zinc from food in humans.

    Science.gov (United States)

    Serfaty-Lacrosniere, C; Wood, R J; Voytko, D; Saltzman, J R; Pedrosa, M; Sepe, T E; Russell, R R

    1995-08-01

    Low gastric pH is generally believed to be an important factor in intestinal mineral absorption. Thus, hypochlorhydria could be an important risk factor for mineral malabsorption and the development of marginal mineral status. We studied whether the hypochlorhydria associated with treatment with the anti-ulcer medication omeprazole, a potent gastric proton pump inhibition, would affect intestinal calcium, phosphorus, magnesium, or zinc absorption from food. Thirteen normal, healthy adults were assigned to either a control group (n = 5) receiving no drug treatment or an omeprazole treatment group (n = 8) to produce increased gastric pH. Omeprazole treatment of normal volunteers resulted in a significant change in postprandial gastric pH (pH 6.4 +/- 0.3 vs. 3.6 +/- 0.5 in control subjects, p hypochlorhydria resulting from short-term omeprazole treatment substantially increases the risk for developing calcium, phosphorus, magnesium, or zinc deficiencies due to mineral malabsorption.

  10. INVESTIGATION FOR THE INFLUENCE OF DIFFERENT MAGNESIUM SULFATE DOSES ON THE CONTENT OF CALCIUM AND CHLORIDE IN BLOOD SERUM OF RATS OF BOTH GENDERS

    Directory of Open Access Journals (Sweden)

    A. V. Voronkov

    2016-01-01

    Full Text Available We have conducted an investigation for the influence of different magnesium sulfate doses on the content of calcium and chloride in blood serum of rats of both genders. As the result of the study, we have established that peroral administration of magnesium sulfate at dose 1.7 g/kg leads to the significant decrease of chlorides content in blood serum of male rats, concerning the control group of animals, and at dose 5 g/kg to the decrease of concentration, chloride as well as calcium in rats of both genders.

  11. Physicochemical changes in dry-cured hams salted with potassium, calcium and magnesium chloride as a partial replacement for sodium chloride.

    Science.gov (United States)

    Aliño, M; Grau, R; Toldrá, F; Barat, J M

    2010-10-01

    The reduction of added sodium chloride in dry-cured ham has been proposed to reduce dietary sodium intake in Mediterranean countries. The effect of substituting sodium chloride with potassium chloride, calcium chloride and magnesium chloride on some physicochemical characteristics of dry-cured ham during processing was evaluated. The results showed that hams salted with a mixture of sodium and potassium chloride registered higher salt concentrations and lower water contents and thus, needed less time to reach the required weight loss at the end of the process. The opposite effect was observed when calcium and magnesium chloride were added to the salt mixture. The observed differences in the texture and colour parameters were mainly due to differences in water and salt content. Copyright (c) 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.

  12. Clinical study on the influence of a fixed-dose combination of famotidine with calcium carbonate and magnesium hydroxide on the bioavailability of famotidine.

    Science.gov (United States)

    Zhai, Qing; Fu, Jun; Huang, Xia; Xu, Bin; Yuan, Yao-Zong; Jiang, Tao; Rong, Zheng-Xing; Chen, Hong-Zhuan

    2008-01-01

    The potential interaction of the H2-receptor antagonist famotidine (CAS 76824-35-6) with calcium carbonate (CAS 471-34-1) and magnesium hydroxide (CAS 1309-42-8) during administration of the famotidine fixed dose combination (FDC) formulation was investigated. A randomized, open-label, two-period, crossover study was carried out on 12 healthy Chinese volunteers. Plasma concentration-time profiles of famotidine were similar with the FDC formulation and common formulation. Confidence interval (90% CI) for maximal concentration (C(max)) and area under the curve (AUC(o-t)) of famoti-dine were 94.8-112.2% and 94.2-112.3%, respectively. These findings suggest that calcium carbonate/magnesium hydroxide antacids have no significant effects on famotidine pharmacokinetics when they are administered together with famotidine as an FDC formulation.

  13. Biochemistry of the normal dura mater of the human brain determination of water, sodium, potassium, calcium, phosphorus, magnesium, copper, iron, sulfur and nitrogen contents

    Directory of Open Access Journals (Sweden)

    Horacio M. Canelas

    1969-06-01

    Full Text Available The concentrations of water, sodium, potassium, calcium, phosphorus, magnesium, copper, iron, sulfur, and nitrogen were determined in samples of apparently normal dura mater removed from 18 subjects recently dead by craniocerebral trauma. The average concentrations expressed in dry weight were: water 79.55 g/100 g ± 2.52; sodium 1.63 mequiv/100 g ±0.27; potassium 3.68 mequiv/100 g ± 0.66; calcium 119.84 mg/100 g ± 107.40; phosphorus 68.2 mg/100 g ± 34.5; magnesium 0.61 mequiv/100 g ± 0.37; copper 249.8 /xg/100 g ± 109.4; iron 0.82 mg/100 g ± 0.28; sulfur 490.7 mg/100 g ± 22.5; nitrogen 3.33 g/100 g ± 0.17.

  14. Precursor preparation for Ca-Al layered double hydroxide to remove hexavalent chromium coexisting with calcium and magnesium chlorides

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Lihua; He, Xiaoman; Qu, Jun; Li, Xuewei; Lei, Zhiwu; Zhang, Qiwu [School of Resources and Environment Engineering, Wuhan University of Technology, Wuhan 430070 (China); Liu, Xinzhong [College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou 350118 (China)

    2017-01-15

    Al(OH){sub 3} and Ca(OH){sub 2} powders are co-ground to prepare a precursor which hydrates into a layered double hydroxide (LDH) phase by agitation in aqueous solution with target hexavalent chromium (Cr(VI)) at room temperature, to achieve an obvious improvement in removal efficiency of Cr(VI) through an easy incorporation into the structure. Although the prepared precursor transforms into LDH phases also when agitated in the solutions of calcium and magnesium chlorides, it incorporates Cr(VI) preferentially to the chloride salts when they coexist. The adsorption isotherm and kinetic studies show that the phenomena occurring on the Al-Ca precursor fit a pseudo-second-order kinetics with a Langmuir adsorption capacity of 59.45 mg/g. Besides, characterizations of the prepared precursor and the samples after adsorption are also performed by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Transmission electron microscope (TEM) to understand the reason of the preferential incorporation of Cr(VI) to the coexisting chloride salts during the LDH phase formation. - Graphical abstract: Activated Ca-Al hydroxides (C{sub 3}A) transformed into Ca-Al-OH compound when agitated in water. Ca-Al precursor (C{sub 3}A) was agitated in a hexavalent chromium (Cr(VI)) solution to form Al-Ca-CrO{sub 4} LDH product. Ca-Al-CrO{sub 4} LDH phase occurred preferentially to Ca-Al-MCl{sub 2} LDH phases in the solutions of calcium and magnesium chlorides, it incorporates Cr(VI) preferentially to the chloride salts when they coexist. - Highlights: • Activated Ca-Al hydroxides transformed into LDH when agitated in water with some inorganic substances. • Hexavalent Cr was incorporated in the LDH structure at high adsorption capacity. • Ca-Al-Cr LDH phase occurred preferentially to Ca-Al-MCl{sub 2} LDH phases with coexistence. • The prepared Ca-Al hydroxides had high performance as adsorbent even with high salinity of the solution.

  15. DEGRADATION OF SM2ZR2O7 THERMAL BARRIER COATING CAUSED BY CALCIUM-MAGNESIUM-ALUMINUM-SILICON OXIDE (CMAS) DEPOSITION

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Honglong; Sheng, Zhizhi; Tarwater, Emily; Zhang, Xingxing; Dasgupta, Sudip; Fergus, Jeffrey

    2015-03-16

    Rare earth zirconates are promising materials for use as thermal barrier coatings in gas turbine engines. Among the lanthanide zirconate materials, Sm2Zr2O7 with the pyrochlore structure has lower thermal conductivity and better corrosion resistance against calcium-magnesium-aluminum-silicon oxide (CMAS). In this work, after reaction with CMAS, the pyrochlore structure transforms to the cubic fluorite structure and Ca2Sm8(SiO4)6O2 forms in elongated grain.

  16. Oxygen- and magnesium-isotope compositions of calcium-aluminum-rich inclusions from Rumuruti (R) chondrites

    Science.gov (United States)

    Rout, S. S.; Bischoff, A.; Nagashima, K.; Krot, A. N.; Huss, G. R.; Keil, K.

    2009-07-01

    We report oxygen- and magnesium-isotope compositions of Ca,Al-rich inclusions (CAIs) from several Rumuruti (R) chondrites measured in situ using a Cameca ims-1280 ion microprobe. On a three-isotope oxygen diagram, δ 17O vs. δ 18O, compositions of individual minerals in most R CAIs analyzed fall along a slope-1 line. Based on the variations of Δ 17O values (Δ 17O = δ 17O - 0.52 × δ 18O) within individual inclusions, the R CAIs are divided into (i) 16O-rich (Δ 17O ˜ -23-26‰), (ii) uniformly 16O-depleted (Δ 17O ˜ -2‰), and (iii) isotopically heterogeneous (Δ 17O ranges from -25‰ to +5‰). One of the hibonite-rich CAIs, H030/L, has an intermediate Δ 17O value of -12‰ and a highly fractionated composition (δ 18O ˜ +47‰). We infer that like most CAIs in other chondrite groups, the R CAIs formed in an 16O-rich gaseous reservoir. The uniformly 16O-depleted and isotopically heterogeneous CAIs subsequently experienced oxygen-isotope exchange during remelting in an 16O-depleted nebular gas, possibly during R chondrite chondrule formation, and/or during fluid-assisted thermal metamorphism on the R chondrite parent asteroid. Three hibonite-bearing CAIs and one spinel-plagioclase-rich inclusion were analyzed for magnesium-isotope compositions. The CAI with the highly fractionated oxygen isotopes, H030/L, shows a resolvable excess of 26Mg ( 26Mg ∗) corresponding to an initial 26Al/ 27Al ratio of ˜7 × 10 -7. Three other CAIs show no resolvable excess of 26Mg ( 26Mg ∗). The absence of 26Mg ∗ in the spinel-plagioclase-rich CAI from a metamorphosed R chondrite NWA 753 (R3.9) could have resulted from metamorphic resetting. Two other hibonite-bearing CAIs occur in the R chondrites (NWA 1476 and NWA 2446), which appear to have experienced only minor degrees of thermal metamorphism. These inclusions could have formed from precursors with lower than canonical 26Al/ 27Al ratio.

  17. Calcium-magnesium carbonate solid solutions from Holocene conglomerate cements and travertines in the Coast Range of California

    Science.gov (United States)

    Barnes, I.; O'Neil, J.R.

    1971-01-01

    Two calcium-magnesium carbonate solid solutions form Holocene travertines and conglomerate cements in fresh water stream channels of the Coast Range of California. Calcite does not yield the {015} diffraction maximum. The {006} diffraction maximum is lacking over most of the range of composition of calcite. Calcite has compositions from CaCO3 to Ca0.5Mg0.5CO3. Dolomite yields both the {006} and {015} diffraction maxima over its entire composition range, Ca0.6Mg0.4CO3 to Ca0.5Mg0.5CO3. The Ca-Mg carbonates form in isotopic equilibrium and thermodynamic disequilibrium from dispersion of Ca2+-rich water into CO32--rich water within the alluvium. The stable isotope data suggest that all the Mg-rich carbonates are primary precipitates and not a result of Mg-substitution in precursor CaCO3. There is a correlation between ??C13 and Mg content of the carbonates which predicts a 5%. fractionation of C13 between dolomite and calcite at sedimentary temperatures. C14 is incorporated in Ca-Mg carbonates forming from C13-poor meteoric waters and C13-rich waters from Cretaceous sediments. C14 ages of the Ca-Mg carbonates are apparent, and cannot be corrected to absolute values. Solution rates of calcite decrease with increasing MgCO3 content; dolomite dissolves slower than any calcite. ?? 1971.

  18. Calcium-Magnesium-Aluminosilicate (CMAS) Infiltration and Cyclic Degradations of Thermal and Environmental Barrier Coatings in Thermal Gradients

    Science.gov (United States)

    Zhu, Dongming; Harder, Bryan; Smialek, Jim; Miller, Robert A.

    2014-01-01

    In a continuing effort to develop higher temperature capable turbine thermal barrier and environmental barrier coating systems, Calcium-Magnesium-Aluminosilicate (CMAS) resistance of the advanced coating systems needs to be evaluated and improved. This paper highlights some of NASA past high heat flux testing approaches for turbine thermal and environmental barrier coatings assessments in CMAS environments. One of our current emphases has been focused on the thermal barrier - environmental barrier coating composition and testing developments. The effort has included the CMAS infiltrations in high temperature and high heat flux turbine engine like conditions using advanced laser high heat flux rigs, and subsequently degradation studies in laser heat flux thermal gradient cyclic and isothermal furnace cyclic testing conditions. These heat flux CMAS infiltration and related coating durability testing are essential where appropriate CMAS melting, infiltration and coating-substrate temperature exposure temperature controls can be achieved, thus helping quantify the CMAS-coating interaction and degradation mechanisms. The CMAS work is also playing a critical role in advanced coating developments, by developing laboratory coating durability assessment methodologies in simulated turbine engine conditions and helping establish CMAS test standards in laboratory environments.

  19. Calcium and magnesium ions modulate the oligomeric state and function of mitochondrial 2-Cys peroxiredoxins in Leishmania parasites.

    Science.gov (United States)

    Morais, Mariana A B; Giuseppe, Priscila O; Souza, Tatiana A C B; Castro, Helena; Honorato, Rodrigo V; Oliveira, Paulo S L; Netto, Luis E S; Tomas, Ana M; Murakami, Mario T

    2017-04-28

    Leishmania parasites have evolved a number of strategies to cope with the harsh environmental changes during mammalian infection. One of these mechanisms involves the functional gain that allows mitochondrial 2-Cys peroxiredoxins to act as molecular chaperones when forming decamers. This function is critical for parasite infectivity in mammals, and its activation has been considered to be controlled exclusively by the enzyme redox state under physiological conditions. Herein, we have revealed that magnesium and calcium ions play a major role in modulating the ability of these enzymes to act as molecular chaperones, surpassing the redox effect. These ions are directly involved in mitochondrial metabolism and participate in a novel mechanism to stabilize the decameric form of 2-Cys peroxiredoxins in Leishmania mitochondria. Moreover, we have demonstrated that a constitutively dimeric Prx1m mutant impairs the survival of Leishmania under heat stress, supporting the central role of the chaperone function of Prx1m for Leishmania parasites during the transition from insect to mammalian hosts. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Automated Measurement of Magnesium/Calcium Ratios in Gastropod Shells Using Laser-Induced Breakdown Spectroscopy for Paleoclimatic Applications.

    Science.gov (United States)

    Cobo, Adolfo; García-Escárzaga, Asier; Gutiérrez-Zugasti, Igor; Setién, Jesús; González-Morales, Manuel R; López-Higuera, José Miguel

    2017-04-01

    The chemical composition of mollusk shells offers information about environmental conditions present during the lifespan of the organism. Shells found in geological deposits and in many archeological sites can help to reconstruct past climatic conditions. For example, a correlation has been found between seawater temperature and the amount of some substituent elements (e.g., magnesium, strontium) in the biogenerated calcium carbonate matrix of the shell, although it is very species-specific. Here we propose the use laser-induced breakdown spectroscopy (LIBS) to estimate Mg/Ca ratios in modern specimens of the common limpet Patella vulgata. An automated setup was used to obtain a sequence of Mg/Ca ratios across a sampling path that could be compared with the seawater temperatures recorded during the organism's lifespan. Results using four shells collected in different months of the year showed a direct relationship between the Mg/Ca ratios and the seawater temperature, although the sequences also revealed small-scale (short-term) variability and an irregular growth rate. Nevertheless, it was possible to infer the season of capture and the minimum and maximum seawater temperatures from the LIBS sequences. This fact, along with the reduction in sampling and measurement time compared with other spectrometric techniques (such as inductively coupled plasma mass spectrometry [ICP-MS]), makes LIBS useful in paleoclimatic studies.

  1. Report on the Study of Radiation Damage in Calcium Fluoride and Magnesium Fluoride Crystals for use in Excimer Laser Applications

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1999-10-04

    A study was performed to investigate the effects of radiation damage in calcium fluoride and magnesium fluoride crystals caused by gamma rays and UV photons from excimer lasers. The purpose was to study and correlate the damage caused by these two different mechanisms in various types of material used for fabricating optical elements in high power excimer lasers and lens systems of lithography tools. These optical systems are easily damaged by the laser itself, and it is necessary to use only the most radiation resistant materials for certain key elements. It was found that a clear correlation exists between the, radiation induced damage caused by high energy gamma rays and that produced by UV photons from the excimer laser. This correlation allows a simple procedure to be developed to select the most radiation resistant material at the ingot level, which would be later used to fabricate various components of the optical system. This avoids incurring the additional cost of fabricating actual optical elements with material that would later be damaged under prolonged use. The result of this screening procedure can result in a considerable savings in the overall cost of the lens and laser system.

  2. Estimation of calcium, magnesium, cadmium, and lead in biological samples from paralyzed quality control and production steel mill workers.

    Science.gov (United States)

    Afridi, Hassan Imran; Talpur, Farah Naz; Kazi, Tasneem Gul; Kazi, Naveed; Arain, Sadaf Sadia; Shah, Faheem

    2015-06-01

    The determination of trace and toxic metals in the biological samples of human beings is an important clinical screening procedure. The aim of the present study was to compare the level of essential trace and toxic elements cadmium (Cd), calcium (Ca), lead (Pb), and magnesium (Mg) in biological samples (whole blood, urine, and scalp hair) of male paralyzed production (PPW) and quality control workers (PQW) of a steel mill, age ranged (35-55 years). For comparison purposes, healthy age-matched exposed referent subjects (EC), working in steel mill and control subjects (NEC), who were not working in industries and lived far away from the industrial areas, were selected as control subjects. The concentrations of electrolytes and toxic elements in biological samples were measured by atomic absorption spectrometry after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked using certified reference materials. The results of this study showed that the mean values of Cd and Pb were significantly higher in scalp hair, blood, and urine samples of PPW and PQW as compared to NEC and EC (p < 0.001), whereas the concentrations of Ca and Mg were found to be lower in the scalp hair and blood but higher in the urine samples of PPW and PQW. The results show the need for immediate improvements in workplace, ventilation, and industrial hygiene practices.

  3. Individual effects of sodium, potassium, calcium, and magnesium chloride salts on Lactobacillus pentosus and Saccharomyces cerevisiae growth.

    Science.gov (United States)

    Bautista-Gallego, J; Arroyo-López, F N; Durán-Quintana, M C; Garrido-Fernandez, A

    2008-07-01

    A quantitative investigation on the individual effects of sodium (NaCl), potassium (KCl), calcium (CaCl2), and magnesium (MgCl2) chloride salts against Lactobacillus pentosus and Saccharomyces cerevisiae, two representative microorganisms of table olives and other fermented vegetables, was carried out. In order to assess their potential activities, both the kinetic growth parameters and dose-response profiles in synthetic media (deMan Rogosa Sharpe broth medium and yeast-malt-peptone-glucose broth medium, respectively) were obtained and analyzed. Microbial growth was monitored via optical density measurements as a function of contact time in the presence of progressive chloride salt concentrations. Relative maximum specific growth rate and lag-phase period were modeled as a function of the chloride salt concentrations. Moreover, for each salt and microorganism tested, the noninhibitory concentrations and the MICs were estimated and compared. All chloride salts exerted a significant antimicrobial effect on the growth cycle; particularly, CaCl2 showed a similar effect to NaCl, while KCl and MgCl2 were progressively less inhibitory. Microbial susceptibility and resistance were found to be nonlinearly dose related.

  4. Urinary excretion of calcium, magnesium, phosphate, citrate, oxalate, and uric acid by healthy schoolchildren using a 12-h collection protocol.

    Science.gov (United States)

    Sáez-Torres, Concepción; Rodrigo, Dolores; Grases, Félix; García-Raja, Ana M; Gómez, Cristina; Lumbreras, Javier; Frontera, Guiem

    2014-07-01

    Improving knowledge about normal urine composition in children is important for early prevention of lithiasis. We describe urinary excretion values of calcium (Ca), magnesium (Mg), phosphate (P), citrate (Cit), uric acid (Ur), and oxalate (Ox) in healthy children with and without a family history of lithiasis, using a 12-h urine collection protocol. Urine samples were obtained from 184 children (5-12 years): a spot sample collected in the afternoon, and a 12-h overnight sample. Solute/creatinine (Cr) and 12-h solute excretion was calculated. Urinary excretion values of the studied solutes are presented as percentile values, separately for each type of sample. Due to age-related differences in the solute/creatinine ratios, except for Ca and Cit, results are described according to the child's age. The presence of excretion values related to an increased risk of lithiasis was more common in children with a family history. We report data from urine samples collected by using a simplified collection protocol. The observed differences between children with and without a family history of lithiasis could justify that in population studies aimed at setting reference values, the former are excluded.

  5. Precursor preparation for Ca-Al layered double hydroxide to remove hexavalent chromium coexisting with calcium and magnesium chlorides

    Science.gov (United States)

    Zhong, Lihua; He, Xiaoman; Qu, Jun; Li, Xuewei; Lei, Zhiwu; Zhang, Qiwu; Liu, Xinzhong

    2017-01-01

    Al(OH)3 and Ca(OH)2 powders are co-ground to prepare a precursor which hydrates into a layered double hydroxide (LDH) phase by agitation in aqueous solution with target hexavalent chromium (Cr(VI)) at room temperature, to achieve an obvious improvement in removal efficiency of Cr(VI) through an easy incorporation into the structure. Although the prepared precursor transforms into LDH phases also when agitated in the solutions of calcium and magnesium chlorides, it incorporates Cr(VI) preferentially to the chloride salts when they coexist. The adsorption isotherm and kinetic studies show that the phenomena occurring on the Al-Ca precursor fit a pseudo-second-order kinetics with a Langmuir adsorption capacity of 59.45 mg/g. Besides, characterizations of the prepared precursor and the samples after adsorption are also performed by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Transmission electron microscope (TEM) to understand the reason of the preferential incorporation of Cr(VI) to the coexisting chloride salts during the LDH phase formation.

  6. Quantitative Proteomic Analysis of the Response to Zinc, Magnesium, and Calcium Deficiency in Specific Cell Types of Arabidopsis Roots

    Directory of Open Access Journals (Sweden)

    Yoichiro Fukao

    2016-01-01

    Full Text Available The proteome profiles of specific cell types have recently been investigated using techniques such as fluorescence activated cell sorting and laser capture microdissection. However, quantitative proteomic analysis of specific cell types has not yet been performed. In this study, to investigate the response of the proteome to zinc, magnesium, and calcium deficiency in specific cell types of Arabidopsis thaliana roots, we performed isobaric tags for relative and absolute quantification (iTRAQ-based quantitative proteomics using GFP-expressing protoplasts collected by fluorescence-activated cell sorting. Protoplasts were collected from the pGL2-GFPer and pMGP-GFPer marker lines for epidermis or inner cell lines (pericycle, endodermis, and cortex, respectively. To increase the number of proteins identified, iTRAQ-labeled peptides were separated into 24 fractions by OFFGFEL electrophoresis prior to high-performance liquid chromatography coupled with mass spectrometry analysis. Overall, 1039 and 737 proteins were identified and quantified in the epidermal and inner cell lines, respectively. Interestingly, the expression of many proteins was decreased in the epidermis by mineral deficiency, although a weaker effect was observed in inner cell lines such as the pericycle, endodermis, and cortex. Here, we report for the first time the quantitative proteomics of specific cell types in Arabidopsis roots.

  7. TRPM7 is involved in angiotensin II induced cardiac fibrosis development by mediating calcium and magnesium influx.

    Science.gov (United States)

    Yu, Yang; Chen, Shaorui; Xiao, Chuyao; Jia, Yanyan; Guo, Jinlei; Jiang, Jianmin; Liu, Peiqing

    2014-05-01

    Cardiac fibrosis is involved in a lot of cardiovascular pathological processes. Cardiac fibrosis can block conduction, cause hypoxia, strengthen myocardial stiffness, create electrical heterogeneity, and hamper systolic ejection, which is associated with the development of arrhythmia, heart failure and sudden cardiac death. Besides the initial stimulating factors, the cardiac fibroblasts (CFs) are the principal responsible cells in the fibrogenesis cascade of events. TRPM7, a member of the TRPM (Melastatin) subfamily, is a non-selective cation channel, which permeates both Ca(2+) and Mg(2+). Here we demonstrated TRPM7 expression in CFs, and 2-APB (TRPM7 inhibitor), inhibited Ang II-induced CTGF, α-SMA expression and CFs proliferation. Besides, knocking down TRPM7 by shRNA, we proved that TRPM7 mediated both calcium and magnesium changes in cardiac fibroblasts which contribute to fibrosis progress. This study suggested that TRPM7 should play a pivotal role in cardiac fibroblast functions associated to cardiac fibrosis development. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  8. STUDY OF THE INFLUENCE OF MAGNESIUM HYDROXIDE ON THE COMBUSTIBILITY PERFORMANCE OF POLYMER COMPOSITIONS BASED ON ETHYLENE VINYL ACETATE COPOLYMER

    Directory of Open Access Journals (Sweden)

    E.V. Chuleyeva

    2017-04-01

    Full Text Available Purpose. To obtain the flame retardants polymer compositions for cables tested the effect of use EVA compositions with magnesium hydroxide, on indicators combustibility polymer. Methodology. We used the method of differential scanning calorimetry and defined heat flux dependence on the test time for each composition at temperatures from 20 °C to 600 °C rate of temperature rise: 50 °C/min, 75 °C/min, 100 °C/min. Using the model of free kinetics we determined dependence of the activation energy from the conversion, a dependence of the conversion on the time of the test, the dependence of the time of the conversion from the temperature for each concentration. To comparison of these parameters for each composition we plotted the dependence of the time of the conversion from the temperature and the dependence the degree of conversion from the time of temperature exposure during the combustion of each of the compositions. Results. We obtained the kinetic characteristics, allowing to determine the composition, which provided the best results to reducing the kinetic parameters of flammability of polymeric compositions. Originality. For the first time we used the DSC and model-free kinetics to determine the effect properties of ingredients of the polymer compositions on the combustibility performance. Practical use. The research results can be used to develop polymer compositions for cable products.

  9. Validation of liquid chromatographic method for analysis of lidocaine hydrochloride, dexamethasone acetate, calcium dobesilate, buthylhydroxyanisol and degradation product hydroquinone in suppositories and ointment.

    Science.gov (United States)

    Zivanovic, Lj; Zecevic, M; Markovic, S; Petrovic, S; Ivanovic, I

    2005-09-23

    In this paper, there was developed a sensitive, precise and accurate reversed-phase liquid chromatographic (RP-HPLC) method and validated for simultaneous determination of lidocaine hydrochloride, dexamethasone acetate (DA) and calcium dobesilate (CD) in suppositories and ointment. Also there was achieved a parallel analysis of buthylhydroxyanisol, as a preservative, and hydroquinone, as a degradation product of calcium dobesilate, present in these dosage forms. The relative standard deviation (RSD) values for all five compounds indicated a good precision and accuracy of the RP-HPLC method. Method is selective, sensitive and reproducible with good recovery values and can be applied in simultaneous determination of all mentioned compounds.

  10. Establishing homology between mitochondrial calcium uniporters, prokaryotic magnesium channels and chlamydial IncA proteins.

    Science.gov (United States)

    Lee, Andre; Vastermark, Ake; Saier, Milton H

    2014-08-01

    Mitochondrial calcium uniporters (MCUs) (TC no. 1.A.77) are oligomeric channel proteins found in the mitochondrial inner membrane. MCUs have two well-conserved transmembrane segments (TMSs), connected by a linker, similar to bacterial MCU homologues. These proteins and chlamydial IncA proteins (of unknown function; TC no. 9.B.159) are homologous to prokaryotic Mg(2+) transporters, AtpI and AtpZ, based on comparison scores of up to 14.5 sds. A phylogenetic tree containing all of these proteins showed that the AtpZ proteins cluster coherently as a subset within the large and diverse AtpI cluster, which branches separately from the MCUs and IncAs, both of which cluster coherently. The MCUs and AtpZs share the same two TMS topology, but the AtpIs have four TMSs, and IncAs can have either two (most frequent) or four (less frequent) TMSs. Binary alignments, comparison scores and motif analyses showed that TMSs 1 and 2 align with TMSs 3 and 4 of the AtpIs, suggesting that the four TMS AtpI proteins arose via an intragenic duplication event. These findings establish an evolutionary link interconnecting eukaryotic and prokaryotic Ca(2+) and Mg(2+) transporters with chlamydial IncAs, and lead us to suggest that all members of the MCU superfamily, including IncAs, function as divalent cation channels. © 2014 The Authors.

  11. Relationship between tap water hardness, magnesium, and calcium concentration and mortality due to ischemic heart disease or stroke in The Netherlands.

    Science.gov (United States)

    Leurs, Lina J; Schouten, Leo J; Mons, Margreet N; Goldbohm, R Alexandra; van den Brandt, Piet A

    2010-03-01

    Conflicting results on the relationship between the hardness of drinking water and mortality related to ischemic heart disease (IHD) or stroke have been reported. We investigated the possible association between tap water calcium or magnesium concentration and total hardness and IHD mortality or stroke mortality. In 1986, a cohort of 120,852 men and women aged 5569 years provided detailed information on dietary and other lifestyle habits. Follow-up for mortality until 1996 was established by linking data from the Central Bureau of Genealogy and Statistics Netherlands. We calculated tap water hardness for each postal code using information obtained from all pumping stations in the Netherlands. Tap water hardness was categorized as soft [hard (1.62.0 mmol/L CaCO3), and hard (> 2.0 mmol/L CaCO3). The multivariate case-cohort analysis was based on 1,944 IHD mortality and 779 stroke mortality cases and 4,114 subcohort members. For both men and women, we observed no relationship between tap water hardness and IHD mortality [hard vs. soft water: hazard ratio (HR) = 1.03; 95% confidence interval (CI), 0.851.28 for men and HR = 0.93; 95% CI, 0.711.21 for women) and stroke mortality (hard vs. soft water HR = 0.90; 95% CI, 0.661.21 and HR = 0.86; 95% CI, 0.621.20, respectively). For men with the 20% lowest dietary magnesium intake, an inverse association was observed between tap water magnesium intake and stroke mortality (HR per 1 mg/L intake = 0.75; 95% CI, 0.610.91), whereas for women with the 20% lowest dietary magnesium intake, the opposite was observed. We found no evidence for an overall significant association between tap water hardness, magnesium or calcium concentrations, and IHD mortality or stroke mortality. More research is needed to investigate the effect of tap water magnesium on IHD mortality or stroke mortality in subjects with low dietary magnesium intake.

  12. [The impact of changes in levels of calcium, phosphate and magnesium during hemodialysis on autonomic system reactivity as measured by heart rate variability analysis].

    Science.gov (United States)

    Buda, S; Stompór, T; Sułowicz, W; Kopeć, J; Szymczakiewicz-Multanowska, A; Janion, M

    2000-01-01

    The aim of the study was to analyze the response of autonomic nervous system to dialysis related systemic volume reduction using heart rate variability (HRV) analysis. The possible relationship between changes in serum levels of calcium-phosphate balance parameters and HRV measurements results was also analyzed. The study was performed in 32 patients (20 men, 12 women) aged between 27 and 71 years (mean 44 years) treated with maintenance dialysis due to end-stage renal disease from 3 months to 15 years (mean 4.4 years). All parameters mentioned above were analyzed during 4-hour dialysis session. Mean value of LF/HF ratio at the beginning of the procedure was 5.36, with continuous increase in consecutive measurements performed 30-minute intervals to the maximal value 8.2 in 120th minute of HD session (p magnesium level during dialysis exceeded 20%. In addition, statistically significant relationship between percentage reduction in magnesium ion concentration and LF/HF ratio during HD was found. Obtained results let us to conclude, that hemodialysis leads to important change in the activity of both components of autonomic nervous system. The factors which may adversely influence the quality of this response may be, among others, low total calcium ion concentration as well as low percentage reduction in magnesium level during hemodialysis session.

  13. Laser Sintered Magnesium-Calcium Silicate/Poly-ε-Caprolactone Scaffold for Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Kuo-Yang Tsai

    2017-01-01

    Full Text Available In this study, we manufacture and analyze bioactive magnesium–calcium silicate/poly-ε-caprolactone (Mg–CS/PCL 3D scaffolds for bone tissue engineering. Mg–CS powder was incorporated into PCL, and we fabricated the 3D scaffolds using laser sintering technology. These scaffolds had high porosity and interconnected-design macropores and structures. As compared to pure PCL scaffolds without an Mg–CS powder, the hydrophilic properties and degradation rate are also improved. For scaffolds with more than 20% Mg–CS content, the specimens become completely covered by a dense bone-like apatite layer after soaking in simulated body fluid for 1 day. In vitro analyses were directed using human mesenchymal stem cells (hMSCs on all scaffolds that were shown to be biocompatible and supported cell adhesion and proliferation. Increased focal adhesion kinase and promoted cell adhesion behavior were observed after an increase in Mg–CS content. In addition, the results indicate that the Mg–CS quantity in the composite is higher than 10%, and the quantity of cells and osteogenesis-related protein of hMSCs is stimulated by the Si ions released from the Mg–CS/PCL scaffolds when compared to PCL scaffolds. Our results proved that 3D Mg–CS/PCL scaffolds with such a specific ionic release and good degradability possessed the ability to promote osteogenetic differentiation of hMSCs, indicating that they might be promising biomaterials with potential for next-generation bone tissue engineering scaffolds.

  14. Calcium and Magnesium Released from Residues in an Integrated Crop-Livestock System under Different Grazing Intensities

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    Joice Mari Assmann

    Full Text Available ABSTRACT Under integrated crop-livestock production systems (ICLS, plant and animal residues are important nutrient stocks for plant growth. Grazing management, by affecting the numbers of both plants and animals and the quality of residues, will influence nutrient release rates. The objective of this study was to evaluate the impact of grazing intensity on Ca and Mg release from pasture, dung, and soybean residues in a long-term no-till integrated soybean-cattle system. The experiment was established in May 2001 in a Latossolo Vermelho Distroférrico (Rhodic Hapludox. Treatments were a gradient of grazing intensity, determined by managing a black oat + Italian ryegrass pasture at 10, 20, 30, and 40 cm grazing height and no-grazing (NG, followed by soybean cropping. Ca and Mg release rates were determined in two entire cycles (2009/11. Moderate grazing (20 and 30 cm sward height led to greater Ca and Mg release rates from pasture and dung residues, with low average half-life values (13 and 3 days for Ca and 16 and 6 days for Mg for pasture and dung, respectively. Grazing compared with NG resulted in greater Ca and Mg release from pasture and dung residues. Grazing intensity did not affect Ca and Mg release rates or amounts from soybean residues, but Ca and Mg release rates were greater from soybean leaves than from stems. Although moderate grazing intensities produce higher quality residues and higher calcium and magnesium release rates, a higher total nutrient amount is released by light grazing intensity and no-grazing, determined by higher residue production. Grazing intensity is, then, important for nutrient dynamics in the soil-plant-animal continuum.

  15. Europium doped di-calcium magnesium di-silicate orange–red emitting phosphor by solid state reaction method

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    Ishwar Prasad Sahu

    2015-07-01

    Full Text Available A new orange–red europium doped di-calcium magnesium di-silicate (Ca2MgSi2O7:Eu3+ phosphor was prepared by the traditional high temperature solid state reaction method. The prepared Ca2MgSi2O7:Eu3+ phosphor was characterized by X-ray diffractometer (XRD, transmission electron microscopy (TEM, field emission scanning electron microscopy (FESEM with energy dispersive x-ray spectroscopy (EDX, fourier transform infrared spectra (FTIR, photoluminescence (PL and decay characteristics. The phase structure of sintered phosphor was akermanite type structure which belongs to the tetragonal crystallography with space group P4¯21m, this structure is a member of the melilite group and forms a layered compound. The chemical composition of the sintered Ca2MgSi2O7:Eu3+ phosphor was confirmed by EDX spectra. The PL spectra indicate that Ca2MgSi2O7:Eu3+ can be excited effectively by near ultraviolet (NUV light and exhibit bright orange–red emission with excellent color stability. The fluorescence lifetime of Ca2MgSi2O7:Eu3+ phosphor was found to be 28.47 ms. CIE color coordinates of Ca2MgSi2O7:Eu3+ phosphor is suitable as orange-red light emitting phosphor with a CIE value of (X = 0.5554, Y = 0.4397. Therefore, it is considered to be a new promising orange–red emitting phosphor for white light emitting diode (LED application.

  16. Expression of transcellular and paracellular calcium and magnesium transport proteins in renal and intestinal epithelia during lactation.

    Science.gov (United States)

    Beggs, Megan R; Appel, Ida; Svenningsen, Per; Skjødt, Karsten; Alexander, R Todd; Dimke, Henrik

    2017-09-01

    Significant alterations in maternal calcium (Ca2+) and magnesium (Mg2+) balance occur during lactation. Ca2+ is the primary divalent cation mobilized into breast milk by demineralization of the skeleton and alterations in intestinal and renal Ca2+ transport. Mg2+ is also concentrated in breast milk, but the underlying mechanisms are not well understood. To determine the molecular alterations in Ca2+ and Mg2+ transport in the intestine and kidney during lactation, three groups of female mice consisting of either nonpregnant controls, lactating mice, or mice undergoing involution were examined. The fractional excretion of Ca2+, but not Mg2+, rose significantly during lactation. Renal 1-α hydroxylase and 24-OHase mRNA levels increased markedly, as did plasma 1,25 dihydroxyvitamin D levels. This was accompanied by significant increases in intestinal expression of Trpv6 and S100g in lactating mice. However, no alterations in the expression of cation-permeable claudin-2, claudin-12, or claudins-15 were found in the intestine. In the kidney, increased expression of Trpv5 and Calb1 was observed during lactation, while no changes in claudins involved in Ca2+ and Mg2+ transport (claudin-2, claudin-14, claudin-16, or claudin-19) were found. Consistent with the mRNA expression, expression of both calbindin-D28K and transient receptor potential vanilloid 5 (TRPV5) proteins increased. Colonic Trpm6 expression increased during lactation, while renal Trpm6 remained unaltered. In conclusion, proteins involved in transcellular Ca2+ and Mg2+ transport pathways increase during lactation, while expression of paracellular transport proteins remained unchanged. Increased fractional Ca2+ excretion can be explained by vitamin D-dependent intestinal hyperabsorption and bone demineralization, despite enhanced transcellular Ca2+ uptake by the kidney. Copyright © 2017 the American Physiological Society.

  17. Calcium

    Science.gov (United States)

    ... Turn to calcium-fortified (or "calcium-set") tofu, soy milk, tempeh, soy yogurt, and cooked soybeans (edamame). Calcium-fortified foods. Look for calcium-fortified orange juice, soy or rice milk, breads, and cereal. Beans. You can get decent ...

  18. Zinc ions efflux from lymphocytes in vitro in the presence of a calcium and magnesium ionic environment and its changes following administration of verapamil.

    Science.gov (United States)

    Tubek, Sławomir

    2007-01-01

    The total and ouabain-dependent rate constants of efflux of zinc (Zn) ions from lymphocytes isolated from healthy subjects were measured in vitro in an environment containing calcium (Ca) and magnesium (Mg) ions. Both the total (ERCt-Zn) and ouabain-dependent (ERCos-Zn) rate constants were higher in the presence of Mg2+, with the the oubain-dependent efflux significantly different 0.29+/-0.07 vs 0.13+/-0.02 with and without Mg2+, respectively (pERCE-Zn was observed in both ionic environments and was higher and statistically significant in the presence of Mg2+: 1.94+/-0.64 vs 2.97+/-1.16 (p<0.025). These results suggest that verapamil has an enhancing effect on Zn efflux from isolated lymphocytes, suggesting that calcium channel blockers might result in better Zn homeostatic regulation in diseases of the cardiovascular system.

  19. Reference intervals of plasma calcium, phosphorus, and magnesium for African grey parrots (Psittacus erithacus) and Hispaniolan parrots (Amazona ventralis).

    Science.gov (United States)

    de Carvalho, Fernanda M; Gaunt, Stephen D; Kearney, Michael T; Rich, Gregory A; Tully, Thomas N

    2009-12-01

    Calcium (Ca), phosphorus (P), and magnesium (Mg) are important elements for body homeostasis in several diseases associated with imbalances in the plasma concentration of these ions. This is the first published report of reference intervals for Mg in association with Ca and P levels for psittacine species. One milliliter of blood was collected from 26 Hispaniolan parrots (Amazona ventralis) and 24 African grey parrots (Psittacus erithacus). The plasma concentrations of Ca, P, and Mg were determined for each sample. Statistical analyses were performed including all data (analysis 1) and after exclusion of the subjects with Ca > or = 14.00 mg/dl (3.5 mmol) (analysis 2). The data from analysis 1 have a narrower interval than that observed in analysis 2. Following the normality test (Shapiro-Wilk, alpha = 0.05), the univariate and mean procedures were run. For the reference intervals, the lower and upper values were used, after elimination of the outliers calculated by Blom scores from the ranked variables. The analysis 1 references for the Hispaniolans were Ca = 8.80-10.40 mg/dl (2.20-2.60 mmol/L), P = 1.80-4.40 mg/dl (0.58-1.42 mmol/L), Mg = 1.80-3.10 mg/dl (0.74-1.27 mmol/L), and Ca:P ratio = 2.62-5.39; for the African greys analysis 1 references were Ca = 8.20-20.20 mg/dl (2.05-5.05 mmol/L), P = 2.50-5.90 mg/dl (0.81-1.91 mmol/L), Mg = 2.10-3.40 mg/dl (0.82-1.4 mmol/L), and Ca:P ratio = 1.81-3.77. The analysis 2 references for the Hispaniolans were Ca = 8.80-10.30 mg/dl (2.20-2.58 mmol/L), P = 1.80-3.80 mg/dl (0.58-1.23 mmol/L), Mg = 1.90-3.00 mg/dl (0.82-1.07 mmol/L), Ca:P ratio = 2.62-5.39; for the African greys analysis 2 references were Ca = 1.07 mmol/L), Ca:P ratio = 1.67-3.50. The results of this study are important for evaluating Mg concentrations in relation to the Ca and P parameters in psittacines. This information will be particularly helpful for veterinarians evaluating the hypocalcemic syndrome in African grey parrots and other disease processes

  20. Magnesium and calcium isotopic characteristics of Tengchong volcanics: Recycling of marine carbonates into the SE Tibetan mantle

    Science.gov (United States)

    Liu, F.; Zhang, Z.; Liu, Y.; Zhu, H.; Kang, J.; Zhang, C.; Sun, W.; Wang, G. Q.

    2015-12-01

    Post-collisional high-K calc-alkaline volcanic rocks are widely distributed in Tengchong in the southeastern margin of Tibetan Plateau. Previous considerable petrological and Sr-Nd-Pb isotopic researches undoubtedly indicate that the mantle beneath Tengchong is heterogeneous and enriched. However, the genesis of such a kind of mantle is still poor understood and needs more constrains. One of the key points lead to the answer to this question is that, is there any recycled carbonate involved? Therefore, Magnesium and calcium isotopic compositions of mantle-derived volcanics should be investigated because they are good candidates to be potentially used to trace recycling of ancient marine carbonates into the mantle. In this study, we report high-precision Mg and Ca isotopic compositions for calc-alkaline volcanic rocks in Tengchong. These volcanic rocks show significantly lighter δ26Mg values (-0.44 to -0.36‰) than the mantle value (-0.25±0.07‰). Similarly, they display lighter δ44Ca values (0.65-0.80‰) than the mantle value (1.05±0.04‰). Because neither δ26Mg nor δ44Ca are correlated with SiO2 (50.8-61.6 wt.%) contents, and there is no relationships between δ26Mg or δ44Ca and typical trace element abundance ratios (e.g. Sm/Yb, Ba/Y), we conclude that magma differentiation or partial melting would lead to limited Mg and Ca isotopes fractionation. Thus, low δ26Mg and δ44Ca signatures of Tengchong volcanic rocks probably reflect that the δ26Mg and δ44Ca characteristics of the underneath mantle source, and are resulted from adding ancient marine carbonates into the primitive mantle which has low Mg and Ca isotopic compositions. Our model simulation using a two end-member mixing between Mg-Ca isotopic compositions of primitive mantle and ancient marine carbonate indicates that carbonates involved in the mantle source is mainly dolostone with minor limestone. Combined with the geotectonic evolution history in Tengchong, we propose that the enriched

  1. Effects of surface application of calcium-magnesium silicate and gypsum on soil fertility and sugarcane yield

    Directory of Open Access Journals (Sweden)

    Carlos Alexandre Costa Crusciol

    2014-12-01

    Full Text Available Lime application recommendations for amendment of soil acidity in sugarcane were developed with a burnt cane harvesting system in mind. Sugarcane is now harvested in most areas without burning, and lime application for amendment of soil acidity in this system in which the sugarcane crop residue remains on the ground has been carried out without a scientific basis. The aim of this study was to evaluate the changes in soil acidity and stalk and sugar yield with different rates of surface application of calcium, magnesium silicate, and gypsum in ratoon cane. The experiment was performed after the 3rd harvest of the variety SP 81-3250 in a commercial green sugarcane plantation of the São Luiz Sugar Mill (47º 25' 33" W; 21º 59' 46" S, located in Pirassununga, São Paulo, in southeast Brazil. A factorial arrangement of four Ca-Mg silicate rates (0, 850, 1700, and 3400 kg ha-1 and two gypsum rates (0 and 1700 kg ha-1 was used in the experiment. After 12 months, the experiment was harvested and technological measurements of stalk and sugar yield were made. After harvest, soil samples were taken at the depths of 0.00-0.05, 0.05-0.10, 0.10-0.20, 0.20-0.40, and 0.40-0.60 m in all plots, and the following determinations were made: soil pH in CaCl2, organic matter, P, S, K, Ca, Mg, H+Al, Al, Si, and base saturation. The results show that the application of gypsum reduced the exchangeable Al3+ content and Al saturation below 0.05 m, and increased the Ca2+ concentration in the whole profile, the Mg2+ content below 0.10 m, K+ below 0.4 m, and base saturation below 0.20 m. This contributed to the effect of surface application of silicate on amendment of soil acidity reaching deeper layers. From the results of this study, it may be concluded that the silicate rate recommended may be too low, since the greater rates used in this experiment showed greater reduction in soil acidity, higher levels of nutrients at greater depths and an increase in stalk and sugar

  2. Dietary magnesium and calcium intake and risk of depression in the general population: A meta-analysis.

    Science.gov (United States)

    Li, Bingrong; Lv, Jing; Wang, Weijing; Zhang, Dongfeng

    2017-03-01

    Several epidemiological studies have evaluated the associations between dietary magnesium (Mg) and calcium (Ca) intake and the risk of depression. However, the results of these studies remain controversial. Thus, we performed a meta-analysis to explore these associations and to investigate the possible dose-response relationship between dietary Mg intake and risk of depression. MEDLINE, Web of Science, Embase, Cochrane CENTRAL, CINAHL database, Chinese National Knowledge Infrastructure, Wan fang databases and Databases of Chinese Scientific and Technical Periodicals were searched for eligible publications up to September 2016. Pooled relative risks with 95% confidence intervals were calculated using random-effects model. Publication bias was estimated using Egger's test and the funnel plot. Dose-response relationship was assessed by restricted cubic spline functions. A total of 17 epidemiological studies from 12 articles were included in the present meta-analysis. Among these studies, 11 studies evaluated the association between dietary Mg intake and risk of depression and 6 studies evaluated the association between dietary Ca intake and risk of depression. When comparing the highest with the lowest intake, the pooled relative risks of depression were 0.81 (95% confidence interval = [0.70, 0.92]) for Mg and 0.66 (95% confidence interval = [0.42, 1.02]) for Ca. Dietary Mg intake was significantly associated with a reduced risk of depression among studies conducted in Asia (relative risk  = 0.57; 95% confidence interval = [0.44, 0.74]) and in studies adjusting for energy intake (relative risk  = 0.73; 95% confidence interval = [0.58, 0.92]). For dose-response analysis, evidence of a nonlinear relationship was found between dietary Mg intake and risk of depression, and the largest risk reductions were observed for 320 mg/day. This meta-analysis indicated that moderate Mg intake may be inversely associated with the risk of depression, which

  3. A comparative study of de-icing salts (sodium chloride and calcium ...

    African Journals Online (AJOL)

    A greenhouse study was conducted on four roadside plants (Festuca rubra, Lolium perenne, Plantago lanceolata and Trifolium repens) to determine the effect of two de-icing salts {Sodium Chloride (NaCl) and calcium magnesium acetate, (CMA)} on their growth. Plants were grown in pots and supplied with solution of ...

  4. Novel biodegradable calcium phosphate/polymer composite coating with adjustable mechanical properties formed by hydrothermal process for corrosion protection of magnesium substrate.

    Science.gov (United States)

    Kaabi Falahieh Asl, Sara; Nemeth, Sandor; Tan, Ming Jen

    2016-11-01

    Ceramic type coatings on metallic implants, such as calcium phosphate (Ca-P), are generally stiff and brittle, potentially leading to the early failure of the bone-implant interface. To reduce material brittleness, polyacrylic acid and carboxymethyl cellulose were used in this study to deposit two types of novel Ca-P/polymer composite coatings on AZ31 magnesium alloy using a one-step hydrothermal process. X-ray diffraction and scanning electron microscopy showed that the deposited Ca-P crystal phase and morphology could be controlled by the type and concentration of polymer used. Incorporation of polymer in the Ca-P coatings reduced the coating elastic modulus bringing it close to that of magnesium and that of human bone. Nanoindentation test results revealed significantly decreased cracking tendency with the incorporation of polymer in the Ca-P coating. Apart from mechanical improvements, the protective composite layers had also enhanced the corrosion resistance of the substrate by a factor of 1000 which is sufficient for implant application. Cell proliferation studies indicated that the composite coatings induced better cell attachment compared with the purely inorganic Ca-P coating, confirming that the obtained composite materials could be promising candidates for surface protection of magnesium for implant application with the multiple functions of corrosion protection, interfacial stress reduction, and cell attachment/cell growth promotion. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1643-1657, 2016. © 2015 Wiley Periodicals, Inc.

  5. Structural characterization of rondorfite, calcium silica chlorine mineral containing magnesium in tetrahedral position [MgO4]6-, with the aid of the vibrational spectroscopies and fluorescence.

    Science.gov (United States)

    Dulski, M; Bulou, A; Marzec, K M; Galuskin, E V; Wrzalik, R

    2013-01-15

    Raman and infrared spectra of rondorfite Ca8Mg(SiO4)4Cl2, a calcium chlorosilica mineral containing magnesium in tetrahedral position, has been studied in terms of spectra-structure relations. Raman spectra have been measured at different excited laser lines: 780 nm, 532 nm, 488 nm and 457 nm. This mineral is characterized by a single sharp intense Raman band at 863 cm(-1) assigned to the ν1 [SiO4]4- (Ag) symmetric stretching mode in the magnesiosilicate pentamer. Due to symmetry restriction the other Raman bands have a small intensity. Two Raman bands observed at 564 cm(-1) and 526 cm(-1) are associated simultaneously with ν4 [MgO4]6- and ν4 [SiO4]4- symmetric and antisymmetric modes where magnesium occurs in the tetrahedral configuration. The weak bands at 422 cm(-1) and 386 cm(-1) are associated with the ν2 bending mode of CaO6 in octahedral configuration, respectively. Moreover the infrared spectrum shows very weak bands associated with the hydroxyl group and/or water molecule. Additionally, the strong fluorescence phenomenon was observed and related to the presence of chlorine atoms, magnesium Mg2+ ions in atypical configuration or point defects. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Preparation of ZnSO4·7H2O using filter cake enriched in calcium and magnesium from the process of zinc hydrometallurgy.

    Science.gov (United States)

    Li, Bo; Wang, Xuanbing; Wei, Yonggang; Wang, Hua; Hu, Guanglai

    2017-11-24

    ZnSO4∙7H2O was prepared using a filter cake enriched in calcium and magnesium that was generated during the process of zinc hydrometallurgy. The study was optimized to obtain process parameters. The results show that the optimal acid leaching parameters are a solid-to-liquid ratio of 1:3.5, a sulfuric acid concentration of 16%, an acid leaching time of 20 min, a final pH of 4.1-4.4, a cooling and settling time of 120 min, an oxidation time of 20 min, a stirring speed of 300 r/min, a H2O2 dosage of 25 mL/L, a crystallization temperature of 20 °C, and a crystallization time of 60 min. The ZnSO4∙7H2O content in the product is 98.6%, and the zinc recovery efficiency is 97.5%. This process is characterized by simple flow and low cost, while the circulation and accumulation problems with calcium and magnesium ions in the zinc hydrometallurgy process are also solved.

  7. A novel pharmaceutical excipient: Coprecipitation of calcium and magnesium silicate using brine-seawater in date palm cellulose as an absorbing host

    Directory of Open Access Journals (Sweden)

    Mohammad Hamaidi

    2017-09-01

    Full Text Available This research aims to produce a cost competitive and innovative pharmaceutical additive with multi-purpose use in the pharmaceutical industry from Saudi Arabia natural resources and bio-wastes. The waste substance, brine, and the naturally occurring compound, sodium silica, were reacted together to produce water insoluble calcium and magnesium silicate salts [WISS]. The purity index WISS was compared with synthetic Mg silicae.The produced particle size was 1.994 µm. Date palm cellulose [DPC] with a high purity index [0.99] was produced from the biomass waste of date palm tree. DPC was used as a host for coprecipitation of synthetic calcium magnesium silicate within its intimate structures. The interaction between the cellulose polymer and silicates is physical in nature. WISS-DPC was more flowable than DPC. In SEM, the particles of DPC were fibrous and irregular in shape, while WISS-DPC showed more regular shape than DPC. Tablets prepared from WISS-DPC were harder and had lower disintegration time at all compression forces compared to those made from DPC. The produced excipient had excellent compaction and disintegration properties and could be used as a superdisintegrant and tablet binder in pharmaceutical industries.

  8. Bioavailability of iodine and hardness (magnesium and calcium salt) in drinking water in the etiology of endemic goitre in Sundarban delta of West Bengal (India).

    Science.gov (United States)

    Chandra, Amar K; Tripathy, Smritiratan; Debnath, Arijit; Ghosh, Dishari

    2007-04-01

    Endemic goitre has been reported from the ecologically diverse Sundarban delta of West Bengal (India). To study the etiological factors for the persistence of endemic goitre, bioavailability of iodine and hardness of water used for drinking in the region were evaluated because these common environmental factors are inversely and directly related with goitre prevalence in several geographical regions. For the present study from 19 Community Development Blocks of Sundarban delta, 19 areas were selected at random. From each area at least 8 drinking water samples were collected and analyzed for iodine and the hardness (calcium and magnesium salt content). Iodine content in the drinking water samples was found in the range from 21 to 119 mg/L and total hardness of drinking water was found to range from 50 to 480 ppm. Presence of magnesium salt was found higher than the calcium salts in most of the samples. These findings suggest that the entire delta region is environmentally iodine sufficient but water is relatively hard and thus possibility of hardness of water for the persistence of endemic goitre may not be ruled out.

  9. High extracellular magnesium inhibits mineralized matrix deposition and modulates intracellular calcium signaling in human bone marrow-derived mesenchymal stem cells.

    Science.gov (United States)

    Zhang, Li; Yang, Chunxi; Li, Jiao; Zhu, Yuchang; Zhang, Xiaoling

    2014-08-08

    Mesenchymal stem cells (MSCs) have the potential to differentiate into several cell types and provide an attractive source of autologous cells for regenerative medicine. However, their cellular biology is not fully understood. Similar to Ca(2+), extracellular Mg(2+) plays an important role in the functions of the skeletal system. Here, we examined the effects of extracellular Mg(2+) on the deposition of calcium phosphate matrix and Ca(2+) signaling with or without ATP stimulation in human bone marrow-derived mesenchymal stem cells (hBMSCs). We found that high extracellular Mg(2+) concentration ([Mg(2+)]e) inhibited extracellular matrix mineralization in hBMSCs in vitro. hBMSCs also produced a dose-dependent decrease in the frequency of calcium oscillations during [Mg(2+)]e elevation with a slight suppression on oscillation amplitude. In addition, spontaneous ATP release was inhibited under high [Mg(2+)]e levels and exogenous ATP addition stimulated oscillation reappear. Taken together, our results indicate that high [Mg(2+)]e modulates calcium oscillations via suppression of spontaneous ATP release and inactivates purinergic receptors, resulting in decreased extracellular mineralized matrix deposition in hBMSCs. Therefore, the high magnesium environment created by the rapid corrosion of Mg alloys may result in the dysfunction of calcium-dependent physiology processes and be disadvantageous to hBMSCs physiology. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Magnesium and Osteoporosis

    Directory of Open Access Journals (Sweden)

    Ferda Özdemir

    2004-03-01

    Full Text Available Osteoporosis (OP is a condition of bone fragility resulting from micro-architectural deterioration and decreased bone mass. OP depends on the interaction of genetic, hormonal, environmental and nutritional factors. Chronic low intakes of vitamin D and possibly magnesium, zinc, fluoride and vitamins K, B12, B6 and folic acid may predispose to osteoporosis. Magnesium is a mineral needed by every cell of your body. It helps maintain normal muscle and nerve function, keeps heart rhythm steady, and bones strong. Mg serves as co-factors for enzymes that help build bone matrix. Magnesium deficiency occurs due to excessive loss of magnesium in urine, gastrointestinal system disorders that cause a loss of magnesium or limit magnesium absorption, or a chronic low intake of magnesium. Signs of magnesium deficiency include confusion, disorientation, loss of appetite, depression, muscle contractions and cramps, tingling, numbness, abnormal heart rhythms, coronary spasm, and seizures. Magnesium deficiency alters calcium metabolism and the hormones that regulates calcium. Several studies have suggested that magnesium supplementation may improve bone mineral density and prevent fractures.

  11. Short-chain fructo-oligosaccharides improve magnesium absorption in adolescent girls with a low calcium intake

    NARCIS (Netherlands)

    Heuvel, E.G.H.M. van den; Muijs, T.; Brouns, F.; Hendriks, H.F.J.

    2009-01-01

    Consumption of fructo-oligosaccharides (FOS) has been shown to improve mineral absorption in the short term, but no long-term effects were studied in girls with a low calcium intake. Therefore, we hypothesized that short- and long-term consumption of short-chain FOS (sc-FOS) improves calcium and

  12. Calcium, Magnesium, and Phosphorus Metabolism, and Parathyroid- Calcitonin Function during Prolonged Exposure to Elevated CO2 Concentrations on Submarines

    Science.gov (United States)

    1975-12-01

    de sous-marins. Undersea Biomed. Res. Sub. Suppl.: S57-S70.—On a etudie le metabolisme du calcium et du phosphore et I’equilibre acido -basique chez...du calcium soit regie par la consomma- tion et l’elimination osseuses de COj. L’equtlibre acido -basique serait regie par les phases de tamponnage

  13. Calcium

    Science.gov (United States)

    ... 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 products such as milk, cheese, and yogurt Leafy, green vegetables Fish with ...

  14. Reported Dietary Intake, Disparity between the Reported Consumption and the Level Needed for Adequacy and Food Sources of Calcium, Phosphorus, Magnesium and Vitamin D in the Spanish Population: Findings from the ANIBES Study †

    Science.gov (United States)

    Olza, Josune; Aranceta-Bartrina, Javier; González-Gross, Marcela; Ortega, Rosa M.; Serra-Majem, Lluis; Varela-Moreiras, Gregorio; Gil, Ángel

    2017-01-01

    Calcium, phosphorus, magnesium and vitamin D have important biological roles in the body, especially in bone metabolism. We aimed to study the reported intake, the disparity between the reported consumption and the level needed for adequacy and food sources of these four nutrients in the Spanish population. We assessed the reported intake for both, general population and plausible reporters. Results were extracted from the ANIBES survey, n = 2009. Three-day dietary reported intake data were obtained and misreporting was assessed according to the European Food Safety Authority (EFSA). Mean ± SEM (range) total reported consumption of calcium, phosphorus, magnesium, and vitamin D for the whole population were 698 ± 7 mg/day (71–2551 mg/day), 1176 ± 8 mg/day, (331–4429 mg/day), 222 ± 2 mg/day (73–782 mg/day), and 4.4 ± 0.1 µg/day (0.0–74.2 µg/day), respectively. In the whole group, 76% and 66%; 79% and 72%; and 94% and 93% of the population had reported intakes below 80% of the national and European recommended daily intakes for calcium, magnesium and vitamin D, respectively; these percentages were over 40% when the plausible reporters were analysed separately. The main food sources were milk and dairy products for calcium and phosphorus, cereals and grains for magnesium and fish for vitamin D. In conclusion, there is an important percentage of the Spanish ANIBES population not meeting the recommended intakes for calcium, magnesium and vitamin D. PMID:28230782

  15. Reported Dietary Intake, Disparity between the Reported Consumption and the Level Needed for Adequacy and Food Sources of Calcium, Phosphorus, Magnesium and Vitamin D in the Spanish Population: Findings from the ANIBES Study.

    Science.gov (United States)

    Olza, Josune; Aranceta-Bartrina, Javier; González-Gross, Marcela; Ortega, Rosa M; Serra-Majem, Lluis; Varela-Moreiras, Gregorio; Gil, Ángel

    2017-02-21

    Calcium, phosphorus, magnesium and vitamin D have important biological roles in the body, especially in bone metabolism. We aimed to study the reported intake, the disparity between the reported consumption and the level needed for adequacy and food sources of these four nutrients in the Spanish population. We assessed the reported intake for both, general population and plausible reporters. Results were extracted from the ANIBES survey, n = 2009. Three-day dietary reported intake data were obtained and misreporting was assessed according to the European Food Safety Authority (EFSA). Mean ± SEM (range) total reported consumption of calcium, phosphorus, magnesium, and vitamin D for the whole population were 698 ± 7 mg/day (71-2551 mg/day), 1176 ± 8 mg/day, (331-4429 mg/day), 222 ± 2 mg/day (73-782 mg/day), and 4.4 ± 0.1 µg/day (0.0-74.2 µg/day), respectively. In the whole group, 76% and 66%; 79% and 72%; and 94% and 93% of the population had reported intakes below 80% of the national and European recommended daily intakes for calcium, magnesium and vitamin D, respectively; these percentages were over 40% when the plausible reporters were analysed separately. The main food sources were milk and dairy products for calcium and phosphorus, cereals and grains for magnesium and fish for vitamin D. In conclusion, there is an important percentage of the Spanish ANIBES population not meeting the recommended intakes for calcium, magnesium and vitamin D.

  16. Study of calcium phosphate (DCPD electrodeposition process on a Mg-3Al-1Zn magnesium alloy surface

    Directory of Open Access Journals (Sweden)

    Filip Pastorek

    2013-02-01

    Full Text Available Evaluation of calcium phosphating process realized on Mg-3Al-1Zn alloy surface after grinding was investigated by electrochemical tests supported by photodocumentation. The electrodeposition treatment was performed by electrochemical method in water solution of Ca(NO32.4H2O, (NH42HPO4 and H2O2. The formation of calcium phosphate was divided into several stages and described using light microscopy. The progress in corrosion protection of created calcium phosphate layer in 0.9% NaCl after particular electrodeposition steps was evaluated by electrochemical impedance spectroscopy. The results in the form of Nyquist plots were analyzed using equivalent circuits.

  17. STUDY OF CALCIUM PHOSPHATE (DCPD ELECTRODEPOSITION PROCESS ON THE Mg-3Al-1Zn MAGNESIUM ALLOY SURFACE

    Directory of Open Access Journals (Sweden)

    Filip Pastorek

    2013-02-01

    Full Text Available Evaluation of calcium phosphating process realized on the Mg-3Al-1Zn alloy surface after grinding was investigated by electrochemical tests supported by photodocumentation. The electrodeposition treatment was performed by electrochemical method in water solution of Ca(NO32.4H2O, (NH42HPO4 and H2O2. The formation of calcium phosphate was divided into several stages and described using light microscopy. The progress in corrosion protection of created calcium phosphate layer in 0.9% NaCl after particular electrodeposition steps was evaluated by electrochemical impedance spectroscopy. The results in the form of Nyquist plots were analyzed using equivalent circuits.

  18. Magnesium Gluconate

    Science.gov (United States)

    Magnesium gluconate is used to treat low blood magnesium. Low blood magnesium is caused by gastrointestinal disorders, prolonged vomiting or ... disease, or certain other conditions. Certain drugs lower magnesium levels as well.This medication is sometimes prescribed ...

  19. Calcium

    Science.gov (United States)

    ... from dietary supplements are linked to a greater risk of kidney stones, especially among older adults. But calcium from foods does not appear to cause kidney stones. For most people, other factors (such as not drinking enough fluids) probably have ...

  20. Serum levels of calcium, selenium, magnesium, phosphorus, chromium, copper and iron--their relation to zinc in rats with induced hypothyroidism.

    Science.gov (United States)

    Baltaci, Abdulkerim Kasim; Mogulkoc, Rasim; Belviranli, Muaz

    2013-06-01

    There is an important relation between thyroid hormones and zinc. Establishment of low zinc levels in hypothyroidism and high levels in hyperthyroidism is a significant proof of this relation. The aim of the present study was to explore changes in serum levels of some elements and their relation to zinc in rats with hypothyroidism. Thirty adult male rats of Sprague-Dawley type were divided into 3 equal groups: group 1, control; group 2, sham-hypothyroidism group supplemented with 10 mg/kg serum physiologic i.p. for 4 weeks; and group 3, hypothyroidism group supplemented with 10 mg/kg propylthiouracil i.p. for 4 weeks. Blood samples were collected from all animals by decapitation and serum calcium, phosphorus, chromium, copper, iron, magnesium, selenium and zinc levels were analyzed using an atomic emission apparatus. Group 3 had lower calcium, selenium and zinc levels, and higher chromium, copper, iron and phosphorus levels (p hypothyroidism leads to changes in serum levels of some elements in rats. These changes may be associated with reduced zinc levels in hypothyroidism.

  1. Photo-luminescent properties of a green or red emitting Tb{sup 3+} or Eu{sup 3+} doped calcium magnesium silicate phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Onani, Martin O., E-mail: monani@uwc.ca.za [Department of Chemistry, University of the Western Cape, Private Bag X17, Bellville 7535 (South Africa); Dejene, Francis B. [Department of Physics, University of the Free State, Qwaqwa Campus, Private Bag X13, Phuthaditjhaba 9866 (South Africa)

    2014-04-15

    This study describes green-emitting Tb{sup 3+} or red-emitting Eu{sup 3+} doped calcium magnesium silicate phosphors by ultraviolet excitation at 335 nm. The rare earth activated amorphous calcium silicate was prepared by a solution–combustion process at 600 °C for 5–10 min. The Ca{sub 2}MgSi{sub 2}O{sub 7} prepared using urea and ammonium nitrate has a tetragonal crystal structure. The resulting Tb{sup 3+}-doped phosphor emitted green light centered at 544 nm. The optimum excitation wavelength within the range 300–400 nm was 335 nm. The intensity and emitting wavelength of the Eu{sup 3+} doped samples can be controlled by annealing in a reducing or oxidizing environment, allowing light to be emitted as green or red. When the reducing environment is optimized, the emission spectrum of Ca{sub 2}MgSi{sub 2}O{sub 7}:Eu{sup 2+} is a broad band at 497 nm.

  2. Physico-chemical and sensory properties of reduced-fat mortadella prepared with blends of calcium, magnesium and potassium chloride as partial substitutes for sodium chloride.

    Science.gov (United States)

    Horita, C N; Morgano, M A; Celeghini, R M S; Pollonio, M A R

    2011-12-01

    Blends of calcium, magnesium and potassium chloride were used to partially replace sodium chloride (50-75%) in reduced-fat mortadella formulations. The presence of calcium chloride reduced the emulsion stability, cooking yield, elasticity and cohesiveness and increased hardness; however, it yielded the best sensory acceptance when 50% NaCl was replaced by 25% CaCl(2) and 25% KCl. There was no effect of the salt substitutes on mortadella color, appearance and aroma. All salt combinations studied showed stable lipid oxidation during its shelf life. The use of a blend with 1% NaCl, 0.5% KCl and 0.5% MgCl(2) resulted in the best emulsion stability, but the worst scores for flavor. This study suggests that it is possible to reduce the sodium chloride concentration by 50% in reduced-fat mortadella using the studied salt combinations with necessary adjustments to optimize the sensory properties (MgCl(2) 25%; KCl 25%) or emulsion stability (CaCl(2) 25%; KCl 25%). Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Role of magnesium in hypertension.

    Science.gov (United States)

    Sontia, Bruno; Touyz, Rhian M

    2007-02-01

    Magnesium affects blood pressure by modulating vascular tone and reactivity. It acts as a calcium channel antagonist, it stimulates production of vasodilator prostacyclins and nitric oxide and it alters vascular responses to vasoactive agonists. Magnesium deficiency has been implicated in the pathogenesis of hypertension with epidemiological and experimental studies demonstrating an inverse correlation between blood pressure and serum magnesium levels. Magnesium also influences glucose and insulin homeostasis, and hypomagnesemia is associated with metabolic syndrome. Although most epidemiological and experimental studies support a role for low magnesium in the pathophysiology of hypertension, data from clinical studies have been less convincing. Furthermore, the therapeutic value of magnesium in the management of hypertension is unclear. The present review addresses the role of magnesium in the regulation of vascular function and blood pressure and discusses the implications of magnesium deficiency in experimental and clinical hypertension, in metabolic syndrome and in pre-eclampsia.

  4. 76 FR 13356 - Magnesium Metal From the People's Republic of China: Continuation of Antidumping Duty Order

    Science.gov (United States)

    2011-03-11

    ...-based reagent mixtures, including lime, calcium metal, calcium silicon, calcium carbide, calcium carbonate, carbon, slag coagulants, fluorspar, nephaline syenite, feldspar, alumina (Al203), calcium.../fly ash, magnesium oxide, periclase, ferroalloys, dolomite lime, and colemanite.\\3\\ \\2\\ This material...

  5. Determinação de cálcio e de magnésio em plantas, por fotometria de chama de absorção Determination of calcium and magnesium in plant material, by absorption flame photometry

    Directory of Open Access Journals (Sweden)

    Ondino Cleante Bataglia

    1972-01-01

    Full Text Available As concentrações de cálcio e magnésio em extratos de plantas podem ser determinadas por fotometria de chama de absorção com a precisão e exatidão requeridas, mediante a adição de lantânio na concentração de 0,1 %,como agente protetor. Para obtenção dos dados utilizou-se um espectrofotômetro Perkin-Elmer, modelo 303, equipado com sistema digital de leitura.A method for determination of calcium and magnesium by absorption flame photometry was studied using a Perkin-Elmer model 303 spectrophotometer equiped with digital concentration readout model DCR1. The study of interferents was carried out with concentration usually present in plant material or even in higher concentrations to get information about the possibility of applying this method to other materials. Within the limits of concentration studied, it was observed that calcium determination was affected by the ions Fe 3+, Al3+ , Mn 2+, Si 4+, PO3-4 and SO2-4 . The ions Mg2+ , K+ , Na+ , Cu2+ , Zn2+ , CI- , NO-3 and ClO-4 had no interference. Magnesium determination was affected only by the presence of the ions Al3+ and Si4+. The use of 0.1% lanthanum solution suppressed the interference of 10 ppm of Al3+, Fe3+ or Mn2+, 50 ppm of Si4+ and 100 ppm of PO3-4 or SO2-4 on a 5 ppm calcium solution. It suppressed also the effect of 10 ppm of Al or 50 ppm of Si in the absorbance of 1 ppm magnesium solution. In the application of the method for calcium and magnesium in plant analysis, 0.200 g of dried plant material was digested with 1 ml of nitric acid and 0.5 ml percloric acid. The volume was completed to 50 ml with distilled water. A portion (2 to 10 ml was transfered to a 50 ml volumetric flask, lanthanum was added to a final concentration of 0.1% and the volume was taken to 50 ml. Calcium and magnesium in plant material were determined using calibration curves, obtained with calcium solutions varying from 0 to 10 ppm and magnesium solutions varying from 0 to 2 ppm (both had 0

  6. Oxygen- and magnesium-isotope compositions of calcium-aluminum-rich inclusions from CR2 carbonaceous chondrites

    Science.gov (United States)

    Makide, Kentaro; Nagashima, Kazuhide; Krot, Alexander N.; Huss, Gary R.; Hutcheon, Ian D.; Bischoff, Addi

    2009-09-01

    We report both oxygen- and magnesium-isotope compositions measured in situ using a Cameca ims-1280 ion microprobe in 20 of 166 CAIs identified in 47 polished sections of 15 CR2 (Renazzo-type) carbonaceous chondrites. Two additional CAIs were measured for oxygen isotopes only. Most CR2 CAIs are mineralogically pristine; only few contain secondary phyllosilicates, sodalite, and carbonates - most likely products of aqueous alteration on the CR2 chondrite parent asteroid. Spinel, hibonite, grossite, anorthite, and melilite in 18 CAIs have 16O-rich (Δ 17O = -23.3 ± 1.9‰, 2 σ error) compositions and show no evidence for postcrystallization isotopic exchange commonly observed in CAIs from metamorphosed CV carbonaceous chondrites. The inferred initial 26Al/ 27Al ratios, ( 26Al/ 27Al) 0, in 15 of 16 16O-rich CAIs measured are consistent with the canonical value of (4.5-5) × 10 -5 and a short duration (magnesium and lower-than-canonical 26Al abundance. Another 16O-enriched (Δ 17O = -20.3 ± 1.2‰) inclusion, a spinel-melilite CAI fragment Gao-Guenie (b) #3, has highly-fractionated oxygen- and magnesium-isotope compositions (˜11 and 23‰/amu, respectively), a deficit of 26Mg, and a relatively low ( 26Al/ 27Al) 0 = (2.0 ± 1.7) × 10 -5. This could be the first FUN ( Fractionation and Unidentified Nuclear effects) CAI found in CR2 chondrites. Because this inclusion is slightly 16O-depleted compared to most CR2 CAIs and has lower than the canonical ( 26Al/ 27Al) 0, it may have experienced multistage formation from precursors with nonsolar magnesium-isotope composition and recorded evolution of oxygen-isotope composition in the early solar nebula over 0.9+2.2-0.7 My. Eight of the 166 CR2 CAIs identified are associated with chondrule materials, indicating that they experienced late-stage, incomplete melting during chondrule formation. Three of these CAIs show large variations in oxygen-isotope compositions (Δ 17O ranges from -23.5‰ to -1.7‰), suggesting dilution by

  7. Novel injectable, self-gelling hydrogel-microparticle composites for bone regeneration consisting of gellan gum and calcium and magnesium carbonate microparticles.

    Science.gov (United States)

    Douglas, Timothy E L; Łapa, Agata; Reczyńska, Katarzyna; Krok-Borkowicz, Małgorzata; Pietryga, Krzysztof; Samal, Sangram Keshari; Declercq, Heidi A; Schaubroeck, David; Boone, Marijn; Van der Voort, Pascal; De Schamphelaere, Karel; Stevens, Christian V; Bliznuk, Vitaliy; Balcaen, Lieve; Parakhonskiy, Bogdan V; Vanhaecke, Frank; Cnudde, Veerle; Pamuła, Elżbieta; Skirtach, Andre G

    2016-11-21

    The suitability of hydrogel biomaterials for bone regeneration can be improved by incorporation of an inorganic phase in particle form, thus maintaining hydrogel injectability. In this study, carbonate microparticles containing different amounts of calcium (Ca) and magnesium (Mg) were added to solutions of the anionic polysaccharide gellan gum (GG) to crosslink GG by release of Ca2+ and Mg2+ from microparticles and thereby induce formation of hydrogel-microparticle composites. It was hypothesized that increasing Mg content of microparticles would promote GG hydrogel formation. The effect of Mg incorporation on cytocompatibility and cell growth was also studied. Microparticles were formed by mixing Ca2+ and Mg2+ and [Formula: see text] ions in varying concentrations. Microparticles were characterized physiochemically and subsequently mixed with GG solution to form hydrogel-microparticle composites. The elemental Ca:Mg ratio in the mineral formed was similar to the Ca:Mg ratio of the ions added. In the absence of Mg, vaterite was formed. At low Mg content, magnesian calcite was formed. Increasing the Mg content further caused formation of amorphous mineral. Microparticles of vaterite and magnesium calcite did not induce GG hydrogel formation, but addition of Mg-richer amorphous microparticles induced gelation within 20 min. Microparticles were dispersed homogeneously in hydrogels. MG-63 osteoblast-like cells were cultured in eluate from hydrogel-microparticle composites and on the composites themselves. All composites were cytocompatible. Cell growth was highest on composites containing particles with an equimolar Ca:Mg ratio. In summary, carbonate microparticles containing a sufficient amount of Mg induced GG hydrogel formation, resulting in injectable, cytocompatible hydrogel-microparticle composites.

  8. The influence of calcium magnesium, and sodium on the spectrographic analysis of natural waters; Estudio de la influencia del calcio, magnesio y sodio en un metodo de analisis espectrografico de aguas naturales

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Guerra, J. P.; Capdevilla, C.

    1969-07-01

    The influences of 1000 {mu}g/ml of calcium and sodium and 300 {mu}g/ml of magnesium, on the spectrographic determination of Al, Ba, Cr, Fe, Li , Mn, Ni, Pb, Sr and Ti, minor constituents in natural waters, have been studied, In order to eliminate them, the elements Ga, In, La, Ti and Zn, as well as a mixture containing 30 % Tl-70 % In, have been tested as spectrochemical buffers. (Author) 7 refs.

  9. Effects of surface application of dolomitic limestone and calcium-magnesium silicate on soybean and maize in rotation with green manure in a tropical region

    Directory of Open Access Journals (Sweden)

    Gustavo Spadotti Amaral Castro

    2015-01-01

    Full Text Available Although lime is currently the material most frequently used to ameliorate soil acidity in Brazil, silicate could efficiently replace this source because of its greater solubility and its greater silicon content, which are beneficial for plant development. This study aimed to evaluate the effects of superficial lime and silicate application on soil chemical attributes as well as on soybean and maize nutrition and grain yields when these crops are grown in rotation with green manure. The experimental design was a complete randomized block with sixteen replicates. Plots were treated with one of two materials for acidity correction (dolomitic lime and calcium/magnesium silicate or with no soil correction, as a control. Silicate corrected soil acidity and increased exchangeable base levels in soil at greater depths faster than does liming. The application of both acidity-correcting materials increased N, Ca and Mg leaf concentrations, and all yield components and grain yield in soybean; but in maize, just silicate also increased N and Si when compared with lime, whereas both acidity-correcting increased just two yield components: grains per ear and mass of 100 grains, resulting in highest grain yield. The application of both acidity-correcting materials increased dry matter production of green manures, but for pigeon pea the silicate provided the best result in this dry-winter region.

  10. The impact of selected preparations of trace elements - magnesium, potassium, calcium, and zinc on the release of diclofenac sodium from enteric coated tablets and from sustained release capsules.

    Science.gov (United States)

    Biernat, Paweł; Musiał, Witold; Gosławska, Dorota; Pluta, Janusz

    2014-01-01

    In an aging society, many patients require long-term treatment. This fact is associated clearly with the simultaneous occurrence of lifestyle diseases such as hypertension, diabetes, and even osteoarthritis. Concomitant medications, which are a common practice, pose a major threat of an interaction between these drugs. Very popular now "fast way of life" that makes people have less and less time to prepare well-balanced meals of high nutritional value. The result of this lifestyle is an increased need for supplementation preparations necessary vitamins and minerals. Given the wide availability of dietary supplements (shops, kiosks, petrol stations) raises the question about the possibility of an interaction between the uncontrolled intake of dietary supplements and medications received in the most common diseases of civilization. The aim of this study was to investigate the effect of the most important minerals (magnesium, potassium, calcium, zinc) contained in the popular nutritional supplements, the release also often used as an anti-pain, anti-inflammatory, diclofenac sodium from the different formulations. Among the many as sodium diclofenac selected two most common: film-coated tablets and sustained release capsules. The study showed a significant effect of minerals on the release of diclofenac sodium and differences that impact, depending on the test form of the drug.

  11. "Slow" Voltage-Dependent Inactivation of CaV2.2 Calcium Channels Is Modulated by the PKC Activator Phorbol 12-Myristate 13-Acetate (PMA.

    Directory of Open Access Journals (Sweden)

    Lei Zhu

    Full Text Available CaV2.2 (N-type voltage-gated calcium channels (Ca2+ channels play key roles in neurons and neuroendocrine cells including the control of cellular excitability, neurotransmitter / hormone secretion, and gene expression. Calcium entry is precisely controlled by channel gating properties including multiple forms of inactivation. "Fast" voltage-dependent inactivation is relatively well-characterized and occurs over the tens-to- hundreds of milliseconds timeframe. Superimposed on this is the molecularly distinct, but poorly understood process of "slow" voltage-dependent inactivation, which develops / recovers over seconds-to-minutes. Protein kinases can modulate "slow" inactivation of sodium channels, but little is known about if/how second messengers control "slow" inactivation of Ca2+ channels. We investigated this using recombinant CaV2.2 channels expressed in HEK293 cells and native CaV2 channels endogenously expressed in adrenal chromaffin cells. The PKC activator phorbol 12-myristate 13-acetate (PMA dramatically prolonged recovery from "slow" inactivation, but an inactive control (4α-PMA had no effect. This effect of PMA was prevented by calphostin C, which targets the C1-domain on PKC, but only partially reduced by inhibitors that target the catalytic domain of PKC. The subtype of the channel β-subunit altered the kinetics of inactivation but not the magnitude of slowing produced by PMA. Intracellular GDP-β-S reduced the effect of PMA suggesting a role for G proteins in modulating "slow" inactivation. We postulate that the kinetics of recovery from "slow" inactivation could provide a molecular memory of recent cellular activity and help control CaV2 channel availability, electrical excitability, and neurotransmission in the seconds-to-minutes timeframe.

  12. Development and characterization of a novel bioresorbable and bioactive biomaterial based on polyvinyl acetate, calcium carbonate and coralline hydroxyapatite

    Directory of Open Access Journals (Sweden)

    Javier Aragón

    2011-03-01

    Full Text Available Coralina® HAP-200 (coralline hydroxyapatite obtained by hydrothermal treatment of marine corals and POVIAC® (polymeric matrix based on PVAc, commercial trade marks were mixed with a natural product from the Cuban sea costs, i.e. calcium carbonate from Porites Porites coral, to obtain a novel bioactive composite with potential use as bone restoration material. The samples were characterized by physical-chemical (FTIR, XRD, SEM, EDS and mechanical studies. It was shown that there is no chemical interaction between the inorganic filler and the polymer matrix, each conserving the original properties of the raw materials. The studied formulation had a compressive strength similar to that reported for trabecular bone. Scanning electron microscopy examination revealed that the addition of CaCO3 induces a change on the morphologic structure of the composite obtained after 30 days of SBF immersion. These composites generate novel biomaterials capable of promoting the deposition of a new phase, a Ca-P layer due to the bioactivity of a Ca2+ precursors.

  13. Magnesium, magnesium alloys, and magnesium composites

    National Research Council Canada - National Science Library

    Gupta, M; Sharon, Nai Mui Ling

    2011-01-01

    "Properties of Magnesium Composites for Material Scientists, Engineers and Selectors is the first book-length reference to provide an insight into current and future magnesium-based materials in terms...

  14. Effect of applied voltage on surface properties of anodised titanium in mixture of β-glycerophosphate (β-GP) and calcium acetate (CA)

    Energy Technology Data Exchange (ETDEWEB)

    Chuan, Lee Te, E-mail: gd130079@siswa.uthm.edu.my; Rathi, Muhammad Fareez Mohamad, E-mail: cd110238@siswa.uthm.edu.my; Abidin, Muhamad Yusuf Zainal, E-mail: cd110221@siswa.uthm.edu.my; Abdullah, Hasan Zuhudi, E-mail: hasan@uthm.edu.my; Idris, Maizlinda Izwana, E-mail: izwana@uthm.edu.my [Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, 86400 Parit Raja, Batu Pahat, Johor (Malaysia)

    2015-07-22

    Anodic oxidation is a surface modification method which combines electric field driven metal and oxygen ion diffusion for formation of oxide layer on the anode surface. This method has been widely used to modify the surface morphology of biomaterial especially titanium. This study aimed to investigate the effect of applied voltage on titanium. Specifically, the titanium foil was anodised in mixture of β-glycerophosphate disodium salt pentahydrate (β-GP) and calcium acetate monohydrate (CA) with different applied voltage (50-350 V), electrolyte concentration (0.04 M β-GP + 0.4 M CA), anodising time (10minutes) and current density (50 and 70 mA.cm{sup −2}) at room temperature. Surface oxide properties of anodised titanium were characterised by digital single-lens reflex camera (DSLR camera), field emission scanning electron microscope (FESEM) and atomic force microscopy (AFM). At lower applied voltage (≤150 V), surface of titanium foils were relatively smooth. With increasing applied voltage (≥250 V), the oxide layer became more porous and donut-shaped pores were formed on the surface of titanium foils. The AFM results indicated that the surface roughness of anodised titanium increases with increasing of applied voltage. The porous and rough surface is able to promote the osseointegration and reduce the suffering time of patient.

  15. Surface properties, crystallinity and optical properties of anodised titanium in mixture of β-glycerophosphate (β-GP) and calcium acetate (CA)

    Energy Technology Data Exchange (ETDEWEB)

    Chuan, Lee Te, E-mail: gd130079@siswa.uthm.edu.my; Abdullah, Hasan Zuhudi, E-mail: hasan@uthm.edu.my; Idris, Maizlinda Izwana, E-mail: izwana@uthm.edu.my [Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, 86400 Parit Raja, Batu Pahat, Johor (Malaysia)

    2015-07-22

    Anodic oxidation is an electrochemical method for the production of ceramic films on a metallic substrate. It had been widely used to deposit the ceramic coatings on the metals surface. This method has been widely used in surface modification of biomaterials especially for dental implants. In this study, the surface morphology, crystallinity and optical properties of titanium foil was modified by anodising in mixture of β-glycerophosphate disodium salt pentahydrate (β-GP) and calcium acetate monohydrate (CA). The experiments were carried out at high voltage (350 V), different anodising time (5 and 10 minutes) and current density (10-70 mA.cm{sup −2}) at room temperature. Anodised titanium was characterised by using field emission scanning electron microscopy (FESEM), X-ray diffractometer (XRD), and UV-Vis spectrometry. The result of the experiment showed that surface morphology, crystallinity and optical properties depended strongly on the current density and anodising time. More porous surface and large amount of anatase and rutile was produced at higher current density and longer anodising time. Apart from that, it is also revealed that the energy band gap of anodised titanium increases as the increase in current density due to the presence of anatase and rutile TiO{sub 2}.

  16. Magnesium basics

    Science.gov (United States)

    Ketteler, Markus

    2012-01-01

    As a cofactor in numerous enzymatic reactions, magnesium fulfils various intracellular physiological functions. Thus, imbalance in magnesium status—primarily hypomagnesaemia as it is seen more often than hypermagnesaemia—might result in unwanted neuromuscular, cardiac or nervous disorders. Measuring total serum magnesium is a feasible and affordable way to monitor changes in magnesium status, although it does not necessarily reflect total body magnesium content. The following review focuses on the natural occurrence of magnesium and its physiological function. The absorption and excretion of magnesium as well as hypo- and hypermagnesaemia will be addressed. PMID:26069819

  17. Magnesium basics

    OpenAIRE

    Jahnen-Dechent, Wilhelm; Ketteler, Markus

    2012-01-01

    As a cofactor in numerous enzymatic reactions, magnesium fulfils various intracellular physiological functions. Thus, imbalance in magnesium status?primarily hypomagnesaemia as it is seen more often than hypermagnesaemia?might result in unwanted neuromuscular, cardiac or nervous disorders. Measuring total serum magnesium is a feasible and affordable way to monitor changes in magnesium status, although it does not necessarily reflect total body magnesium content. The following review focuses o...

  18. 21 CFR 184.1721 - Sodium acetate.

    Science.gov (United States)

    2010-04-01

    ... synthetically by the neutralization of acetic acid with sodium carbonate or by treating calcium acetate with...(n)(43) of this chapter. (e) Prior sanctions for this ingredient different from the uses established...

  19. Minerals and Sarcopenia; The Role of Calcium, Iron, Magnesium, Phosphorus, Potassium, Selenium, Sodium, and Zinc on Muscle Mass, Muscle Strength, and Physical Performance in Older Adults: A Systematic Review.

    Science.gov (United States)

    van Dronkelaar, Carliene; van Velzen, Aafke; Abdelrazek, Maya; van der Steen, Anouk; Weijs, Peter J M; Tieland, Michael

    2017-07-12

    Minerals may contribute to prevent and treat sarcopenia, the age-related loss of muscle mass, muscle strength, and physical performance. So far, there is no comprehensive review on the impact of minerals on sarcopenia outcomes. The aim of this systematic review is to evaluate the role of calcium, iron, magnesium, phosphorus, potassium, selenium, sodium, and zinc on muscle mass, muscle strength, and physical performance in older adults. A systematic search was conducted between March 2016 and July 2016, in the PubMed database using predefined search terms. Articles on the role of dietary mineral intake or mineral serum concentrations on muscle mass, muscle strength, physical performance, and/or the prevalence of sarcopenia in healthy or frail older adults (average age ≥ 65 years) were selected. Only original research publications were included. The search and data extraction were conducted in duplicate by 2 independent researchers. The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement was followed in constructing this systematic review. The Effective Public Health Practice Project (EPHPP) Quality Assessment Tool for Quantitative Studies was used to evaluate the quality of the selected articles. From the 3346 articles found, a total of 10 studies met the inclusion criteria. Observational studies showed that serum selenium (n = 1) and calcium intake (n = 1) were significantly associated with muscle mass, and magnesium (n = 1), selenium (n = 1), iron (n = 1), and zinc (n = 1) intake were significantly and positively associated with physical performance in older adults. Furthermore, magnesium (n = 2), selenium (n = 2), calcium (n = 2), and phosphorus (n = 1) intake were associated with the prevalence of sarcopenia. Magnesium supplementation improved physical performance based on one randomized controlled trial. No studies on the role of sodium or potassium on muscle mass, muscle strength, or physical performance were

  20. 76 FR 57021 - Magnesium Metal From the People's Republic of China: Rescission of Antidumping Duty...

    Science.gov (United States)

    2011-09-15

    ... magnesium-based reagent mixtures, including lime, calcium metal, calcium silicon, calcium carbide, calcium carbonate, carbon, slag coagulants, fluorspar, nephaline syenite, feldspar, alumina (Al203), calcium.../fly ash, magnesium oxide, periclase, ferroalloys, dolomite lime, and colemanite.\\11\\ \\10\\ The material...

  1. Evaluation of Pulp and Paper Properties obtained from Maple Juvenile Wood through Organosolv Alcohol Method Catalyzed by Calcium and Magnesium Salts

    Directory of Open Access Journals (Sweden)

    Reza Naghdi

    2015-05-01

    Full Text Available The properties of catalyzed organosolv pulp obtained from maple juvenile wood were studied. The physical properties of fiber (e.g. length, width, and cell membrane thickness and chemical composition of maple juvenile wood (e.g. average cellulose, lignin, extractives, and ash content were determined. The variables were cooking temperature (190 and 200 ºC and time (40, 60, and 80 minutes. Chemical charge ( 280 ml methanol, 70 ml water, and 0.025 mols of Calcium Chloride and Magnesium Nitrate was kept constant. Pulp screen yields (54.9 to 60.91% and Kappa No. (15.5 to 18.4 were measured. Pulp freeness was reduced to 350 ml CSF in PFI mill, and ten 60 g/m2 handsheets were made from the selected pulps. The strength properties of catalyzed organosolv handsheets including tear length (3.83 to 4.25 km, tear index (10.22 to 12.81 mN.m2/g, and burst index (1.74 to 2.15 kPa.m2/g were compared with those of the conventional Kraft handsheets of maple juvenile wood. The least allowed values of the mentioned properties in the Indian (IS and Japanese international standards (JIS reveal that while the tear length value is slightly below that of the standards, the values of tear and burst indices are well beyond the given standards, and the environmentally-friendly catalyzed organosolv pulping process (higher yield and lower Kappa No. compared to Kraft can be recommended to produce paper pulp from maple juvenile wood.

  2. Evaluation of status of calcium, magnesium, potassium, and sodium levels in biological samples in children of different age groups with normal vision and night blindness.

    Science.gov (United States)

    Afridi, Hassan Imran; Kazi, Tasneem Gul; Kazi, Naveed; Kandhro, Ghulam Abbas; Baig, Jameel Ahmed; Shah, Abdul Qadir; Khan, Sumaira; Kolachi, Nida Fatima; Wadhwa, Sham Kumar; Shah, Faheem

    2011-01-01

    The most common cause of blindness in developing countries is vitamin A deficiency. The World Health Organization (WHO) estimates 13.8 million children have some degree of visual loss related to vitamin A deficiency. The causes of night blindness in children are multifactorial and particular consideration has been given to childhood nutritional deficiency, which is the most common problem found in underdeveloped countries. Such deficiency can result in physiological and pathological processes that in turn influence biological sample composition. Vitamin and mineral deficiency prevents more than two billion people from achieving their full intellectual and physical potential. This study was designed to compare the levels of magnesium (Mg), calcium (Ca), potassium (K), and sodium (Na) in scalp hair, serum, blood, and urine of night blindness children in two age groups, (1-5) and (6-10) years, of both genders comparing them to sex- and age-matched controls. A microwave assisted wet acid digestion procedure was developed as a sample pretreatment for the determination of Mg, Ca, K, and Na in biological samples of children with night blindness. The proposed method was validated by using conventional wet digestion and certified reference samples of hair, serum, blood, and urine. The digests of all biological samples were analysed for Mg, Ca, K, and Na by flame atomic absorption spectrometry (FAAS) using an air/acetylene flame. The results indicated significantly lower levels of Mg, Ca, and K in the biological samples (blood, serum, and scalp hair) of male and female children with night blindness and higher values of Na compared with control subjects of both genders. These data present guidance to clinicians and other professionals investigating deficiency of essential mineral elements in biological samples (scalp hair, serum, and blood) of children with night blindness.

  3. Non-free ionic transport of sodium, magnesium, and calcium in streams of two adjacent headwater catchments with different vegetation types in Japan

    Science.gov (United States)

    Terajima, Tomomi; Moriizumi, Mihoko; Nakamura, Tomohiro

    2017-01-01

    Sodium (Na), magnesium (Mg), calcium (Ca) are usually believed to occur mostly as free ions in the fresh water and consequently little is known about their chemical species. To understand the importance of non-free ionic fractions (NIF) of major metals in freshwater streams, Na, Mg, Ca, silicon (Si), and fulvic acid-like materials (FAM) were measured in streams of mountainous adjacent headwater catchments dominated by different vegetation types (planted evergreen coniferous forest and natural deciduous broadleaf forest). During both no rainfall periods and rainstorms, the proportion of NIF relative to total elements was lower in the coniferous catchment than in the deciduous catchment, although it sometimes accounted for half or more of the total concentrations of Na, Mg, and Ca in both catchments. The solubility of metal compounds was higher than the measured maximum concentrations of Na+, Mg2+, and Ca2+ to the extent that inorganic bonding was hardly possible. During no rainfall periods when FAM was slightly produced into the streams, the fluxes of NIF and Si were highly correlated (r > 0.92, p NIF correlated weakly with that of Si but did not correlate with that of FAM in both catchments. In contrast, during a heavy rainstorm, the flux of NIF correlated strongly (r ⩾ 0.83, p NIF originated in the quick-flow component (i.e., surface or near-surface water) in stream water (ΔNIF) correlated strongly (r ⩾ 0.81, p < 0.0001, n = 22) with that of FAM. These findings imply that heavy rainstorms may enhance the bonding of the major metals with humic substances mainly in the deciduous catchment; and also exhibit that, in the headwater catchments, both water flow pathways resulted from the different vegetation types play a very important role to promote the bonding of major metals with humic substances in stream water.

  4. Deep formation waters of Western Europe, Russia and North America characterised by sodium, calcium, magnesium and chloride concentrations

    Science.gov (United States)

    Bozau, Elke; Hemme, Christina; Sattler, Carl-Diedrich; van Berk, Wolfgang

    2015-04-01

    Deep formation water can be classified according to depth, temperature, and salinity (e.g., Graf et al. 1966, Kharaka & Hanor 2007). Most of the deep formation waters contain dissolved solids in excess of sea water. The hydrogeochemical development of formation water has been discussed for a long time. It is widely accepted that deep aquifers are influenced by the meteoric cycle and geochemical processes within the crust (e.g., Hebig et al. 2012). Similar hydrogeochemical signatures are found in deep formation waters of all continents and can be explained by general geochemical processes within the deep reservoirs (e.g., Land 1995). Therefore, data of deep formation waters from Western Europe, Russia, and North America are collected and classified by the major water components. The data are used to identify important hydrogeochemical processes (e.g., halite dissolution and albitisation) leading to different compositions of formation water. Two significant water types are identified: Na-Cl water and Na-Ca-Cl water. Based on the collected hydrogeochemical data, development trends are stated for the formation waters, and albitisation is favoured as the main process for calcium enrichment. Furthermore, differences of formation water according to stratigraphical units are shown for deep reservoirs of the North German Basin and the North Sea. References: Graf, D.L., 1982. Chemical osmosis, reverse chemical osmosis, and the origin of subsurface brines. Geochimica Cosmochimica Acta 46, 1431-1448. Hebig, K.H., Ito, N., Scheytt, T., Marui, A., 2012. Review: Deep groundwater research with focus on Germany. Hydrogeology Journal 20, 227-243. Kharaka, Y.K., Hanor, J.S., 2007. Deep fluids in continents: I. Sedimentary Basins. Treatise on Geochemistry 5, 1-48. Land, L.S., 1995. The role of saline formation water in the crustal cycling. Aquatic Geochemistry 1, 137-145. Acknowledgements: The presented data are results of the collaborative research program "gebo" (Geothermal energy

  5. Magnesium Hydroxide

    Science.gov (United States)

    Magnesium hydroxide is used on a short-term basis to treat constipation.This medication is sometimes prescribed for ... Magnesium hydroxide come as a tablet and liquid to take by mouth. It usually is taken as needed ...

  6. Magnesium Oxide

    Science.gov (United States)

    Magnesium is an element your body needs to function normally. Magnesium oxide may be used for different reasons. Some people use it as ... daily depending on which brand is used and what condition you have. Follow the directions on the ...

  7. Magnesium and cardiovascular system.

    Science.gov (United States)

    Shechter, Michael

    2010-06-01

    Hypomagnesemia is common in hospitalized patients, especially in the elderly with coronary artery disease (CAD) and/or those with chronic heart failure. Hypomagnesemia is associated with an increased incidence of diabetes mellitus, metabolic syndrome, mortality rate from CAD and all causes. Magnesium supplementation improves myocardial metabolism, inhibits calcium accumulation and myocardial cell death; it improves vascular tone, peripheral vascular resistance, afterload and cardiac output, reduces cardiac arrhythmias and improves lipid metabolism. Magnesium also reduces vulnerability to oxygen-derived free radicals, improves human endothelial function and inhibits platelet function, including platelet aggregation and adhesion, which potentially gives magnesium physiologic and natural effects similar to adenosine-diphosphate inhibitors such as clopidogrel. The data regarding its use in patients with acute myocardial infarction (AMI) is conflicting. Although some previous, relatively small randomized clinical trials demonstrated a remarkable reduction in mortality when administered to relatively high risk AMI patients, two recently published large-scale randomized clinical trials (the Fourth International Study of Infarct Survival and Magnesium in Coronaries) failed to show any advantage of intravenous magnesium over placebo. Nevertheless, there are theoretical potential benefits of magnesium supplementation as a cardioprotective agent in CAD patients, as well as promising results from previous work in animal and humans. These studies are cost effective, easy to handle and are relatively free of adverse effects, which gives magnesium a role in treating CAD patients, especially high-risk groups such as CAD patients with heart failure, the elderly and hospitalized patients with hypomagnesemia. Furthermore, magnesium therapy is indicated in life-threatening ventricular arrhythmias such as Torsades de Pointes and intractable ventricular tachycardia.

  8. Photosynthetic and growth response of sugar maple (Acer saccharum Marsh.) mature trees and seedlings to calcium, magnesium, and nitrogen additions in the Catskill Mountains, NY, USA

    Science.gov (United States)

    Momen, Bahram; Behling, Shawna J; Lawrence, Gregory B.; Sullivan, Joseph H

    2015-01-01

    Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (Aqe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the

  9. Effects of calcium magnesium carbonate and roughage level on feedlot performance, ruminal metabolism, and site and extent of digestion in steers fed high-grain diets.

    Science.gov (United States)

    Crawford, G I; Keeler, C D; Wagner, J J; Krehbiel, C R; Erickson, G E; Crombie, M B; Nunnery, G A

    2008-11-01

    A feedlot growth performance experiment and 2 metabolism experiments were conducted to evaluate dietary roughage concentration and calcium magnesium carbonate in steers fed a high-grain diet. In Exp. 1, one hundred ninety-two crossbred yearling steers (320 +/- 10 kg of initial BW) were fed diets based on steam-flaked corn with 0, 0.75, or 1.5% CaMg(CO(3))(2). There were no effects (P > or = 0.13) on ADG, DMI, G:F, or total water intake due to CaMg(CO(3))(2). In Exp. 2, five ruminally and duodenally fistulated steers (263 +/- 9 kg of initial BW) were used in a 5 x 5 Latin square design, with 5 dietary treatments arranged in a 2 x 2 + 1 factorial: 1) 3.8% dietary roughage and no CaMg(CO(3))(2); 2) 7.6% dietary roughage and no CaMg(CO(3))(2); 3) 11.4% dietary roughage and no CaMg(CO(3))(2); 4) 3.8% dietary roughage and 1.5% CaMg(CO(3))(2); and 5) 7.6% dietary roughage and 1.5% CaMg(CO(3))(2). Water consumption was less (quadratic, P = 0.003) when 7.6% dietary roughage was fed compared with 3.8 or 11.4% dietary roughage. Intake of DM was not affected (P > or = 0.16) by dietary roughage or by CaMg(CO(3))(2). Poststomach and total tract starch digestion decreased (linear, P digestibility decreased linearly (P = 0.01), and ruminal pH increased linearly (P = 0.01) with increasing dietary roughage concentration. Inclusion of CaMg(CO(3))(2) can replace limestone and MgO but did not produce ruminal pH responses similar to those observed by increasing dietary roughage in high-concentrate diets.

  10. Intake of dairy products, calcium, magnesium, and phosphorus in childhood and age at menarche in the Tehran Lipid and Glucose Study.

    Directory of Open Access Journals (Sweden)

    Fahimeh Ramezani Tehrani

    Full Text Available PURPOSE: Studies indicate that milk intake is associated with insulin-like growth factor 1 (IGF-1 concentrations and height in childhood, whether milk and other dairy products promote puberty remains unclear. This study aimed to investigate influences of pre-pubertal intakes of milk, yogurt and cheese on menarcheal age in Tehranian girls. The associations of total dietary calcium (Ca, magnesium (Mg, and phosphorus (P with menarcheal age were also examined. METHODS: This prospective study was conducted on 134 pre-pubertal girls, aged 4-12 years at baseline, who participated in the Tehran Lipid and Glucose Study (TLGS, and were followed for a median of 6.5 years. Dietary intakes were determined at initiation of the study using two non-consecutive 24-h dietary recalls and the age of menarche was documented during the follow-up. Logistic regression was used to calculate the risk of reaching menarche ≤ 12 years according to pre-pubertal levels of dairy or mineral intakes. RESULTS: The risk of earlier menarche was higher in girls with higher intakes of milk [OR: 2.28 (95% CI: 1.03-5.05], Ca [OR: 3.20 (95%CI: 1.39-7.42], Mg [OR: 2.43 (95% CI: 1.12-5.27] and P [OR: 3.37 (95 % CI: 1.44-7.87 after controlling for energy and protein intake, interval between the age at study initiation and the age of menarche, and maternal age at menarche (Model 1. Girls in the middle tertile of cheese intakes had a lower risk of reaching menarche ≤ 12 years than those in the lowest tertile after controlling for covariates in model 1. These associations remained significant after further adjustment of BMI Z-score at baseline. The relationship of Ca, Mg, and P with menarche remained after further adjustment for height Z-score at baseline, whereas the association between milk and cheese intakes became non-significant. CONCLUSIONS: Pre-pubertal intake of milk, but not cheese and yogurt, may hasten age at menarche.

  11. Magnesium implant alloy with low levels of strontium and calcium: The third element effect and phase selection improve bio-corrosion resistance and mechanical performance

    Energy Technology Data Exchange (ETDEWEB)

    Bornapour, M., E-mail: mandana.bornapour@mail.mcgill.ca [Light Metals and Advanced Magnesium Materials, Mining and Materials Engineering, McGill University, Montreal, QC H3A 2B2 (Canada); Biointerface Lab, Mining and Materials Engineering, McGill University, Montreal, QC H3A 2B2 (Canada); Celikin, M. [Light Metals and Advanced Magnesium Materials, Mining and Materials Engineering, McGill University, Montreal, QC H3A 2B2 (Canada); Cerruti, M. [Biointerface Lab, Mining and Materials Engineering, McGill University, Montreal, QC H3A 2B2 (Canada); Pekguleryuz, M. [Light Metals and Advanced Magnesium Materials, Mining and Materials Engineering, McGill University, Montreal, QC H3A 2B2 (Canada)

    2014-02-01

    Low density, non-toxicity, biodegradability and mechanical properties similar to human tissues such as bone make magnesium (Mg) alloys attractive for biomedical applications ranging from bone to cardiovascular implants. The most important challenge that still prevents the widespread use of Mg implants is their rapid degradation rate. In this study we investigate the combined effect of calcium (Ca) and strontium (Sr) on the corrosion behavior of Mg via in vitro immersion and electrochemical tests in simulated body fluid (SBF), and analyze changes in mechanical properties. We show that the combined addition of 0.3 wt.% Sr and 0.4 wt.% Ca decreases the corrosion rate of Mg both in terms of mass loss and hydrogen evolution more effectively than the single addition of either alloying element. We investigate the microstructure of as-cast specimens and the morphology of the corrosion products using optical microscopy, scanning electron microscopy, electron probe micro-analysis, X-ray diffraction, and X-ray photoelectron spectroscopy. Tensile and three point bending tests reveal that the ternary alloy Mg–0.3Sr–0.3Ca has a good combination of mechanical properties and corrosion resistance with hydrogen evolution rates of 0.01 mL/cm{sup 2}/h in SBF. Higher concentrations of Sr and Ca alter the resulting microstructure leading to increased corrosion rates in SBF by promoting the micro-galvanic corrosion between the α-Mg matrix and intermetallic phases of Mg{sub 17}Sr{sub 2} and Mg{sub 2}Ca along the grain boundaries. These results indicate that the combined addition of optimal amounts of Ca and Sr is a promising approach to decrease the high degradation rate of Mg implants in physiological conditions, as well as attaining high ductility in the alloy. The better properties of the Mg–0.3Sr–0.3Ca alloy are related to the new intermetallic phases found in this sample. The optimum composition is attributed to the “third element effect”, as seen in the corrosion

  12. Photosynthetic and Growth Response of Sugar Maple (Acer saccharum Marsh.) Mature Trees and Seedlings to Calcium, Magnesium, and Nitrogen Additions in the Catskill Mountains, NY, USA.

    Science.gov (United States)

    Momen, Bahram; Behling, Shawna J; Lawrence, Greg B; Sullivan, Joseph H

    2015-01-01

    Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (Aqe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the forest floor

  13. Magnesium and Vascular Changes in Hypertension

    OpenAIRE

    Ana Rosa Cunha; Bianca Umbelino; Margarida L. Correia; Mario Fritsch Neves

    2012-01-01

    Many factors have been implicated in the pathogenesis of hypertension, including changes in intracellular concentrations of calcium, sodium, potassium, and magnesium. There is a significant inverse correlation between serum magnesium and incidence of cardiovascular diseases. Magnesium is a mineral with important functions in the body such as antiarrhythmic effect, actions in vascular tone, contractility, glucose metabolism, and insulin homeostasis. In addition, lower concentrations of magnesi...

  14. Magnesium, magnesium alloys, and magnesium composites

    National Research Council Canada - National Science Library

    Gupta, M; Sharon, Nai Mui Ling

    2011-01-01

    .... With the popularity of magnesium-based materials in the automotive, aerospace, electronics, and sports equipment industries, and its unique role as a lightweight, energy-saving and high-performance...

  15. Magnesium, magnesium alloys, and magnesium composites

    National Research Council Canada - National Science Library

    Gupta, M; Sharon, Nai Mui Ling

    2011-01-01

    ... of science, characteristics, and applications. It emphasizes the properties of magnesium-based composites and the effects of different types of reinforcements, from micron length to nanometer scale, on the properties of the resulting composites...

  16. Magnesium and Vascular Changes in Hypertension

    Directory of Open Access Journals (Sweden)

    Ana Rosa Cunha

    2012-01-01

    Full Text Available Many factors have been implicated in the pathogenesis of hypertension, including changes in intracellular concentrations of calcium, sodium, potassium, and magnesium. There is a significant inverse correlation between serum magnesium and incidence of cardiovascular diseases. Magnesium is a mineral with important functions in the body such as antiarrhythmic effect, actions in vascular tone, contractility, glucose metabolism, and insulin homeostasis. In addition, lower concentrations of magnesium are associated with oxidative stress, proinflammatory state, endothelial dysfunction, platelet aggregation, insulin resistance, and hyperglycemia. The conflicting results of studies evaluating the effects of magnesium supplements on blood pressure and other cardiovascular outcomes indicate that the action of magnesium in the vascular system is present but not yet established. Therefore, this mineral supplementation is not indicated as part of antihypertensive treatment, and further studies are needed to better clarify the role of magnesium in the prevention and treatment of cardiovascular diseases.

  17. Calcium, Magnesium and Total Antioxidant Capacity (TAC in Seminal Plasma of Water Buffalo (Bubalus Bubalis Bulls and their Relationships with Semen Characteristics

    Directory of Open Access Journals (Sweden)

    Mohammad-Hassan Khadem Ansari

    2010-06-01

    Full Text Available In order to determine calcium (Ca, magnesium (Mg content and total antioxidant capacity (TAC of seminal plasma in buffalo and to study their associations with the semen characteristics, 54 semen samples were collected from 10 buffalo bulls; semen quality was evaluated, seminal plasma was then harvested by centrifugation and its Ca and Mg content were estimated and its TAC determined. The Ca and Mg content of the seminal plasma (Mean ± SEM were recorded as 22.36 ± 0.52 mg dl-1 and 11.94 ± 0.36 mg dl-1 respectively, while, its mean TAC value was 1.50 ± 0.02 mmol L-1. The mean Ca value was highly associated with sperm progressive motility, gross motility, viability (P = 0.000 for all, negatively with semen volume (P = 0.01, and with Mg and TAC values (P = 0.000 for both. The mean Mg values was highly associated with sperm progressive motility, gross motility and viability and seminal plasma Ca and TAC (P = 0.000 for all and negatively associated with semen volume (P = 0.014. The mean TAC values was highly associated with sperm progressive motility, gross motility and viability and seminal plasma Ca and Mg (P = 0.000 for all. For further clarification of these associations, the data was categorized in three groups of excellent (Ex, >90% motile, n = 33, good (Go, 80-89% motile, n = 15 and moderate (Mo, <79% motile, n = 6 according to their percentage of sperm motility. The mean progressive motility in Ex group was 92.24 ± 0.51%, in Go group it was 81.66 ± 0.62 %, and in Mo group it was 71.66 ± 1.05 %. The mean Ca, Mg and TAC values were respectively recorded as 25.12 ± 0.29 mg dl-1, 13.78 ± 0.20 mg dl-1, and 1.57 ± 0.009 mmol L-1 in Ex, 18.74 ± 0.63 mg dl-1, 9.14 ± 0.33mg dl-1, and 1.42 ± 0.044 mmol L-1 in Go, and 17.34 ± 0.18 mg dl-1, 8.06 ± 0.25 mg dl-1, and 1.23± 0.05 mmol L-1 in Mo groups. The associations in groups are discussed. These results show that seminal plasma Ca and Mg content and TAC are associated with semen

  18. Eficiencia del proceso de lavado en la obtención del citrato de calcio y magnesio a escala de banco Effectiveness of washout process to obtain calcium and magnesium citrate at bench scale

    Directory of Open Access Journals (Sweden)

    Jorge E Rodríguez Chanfrau

    2010-03-01

    Full Text Available Como parte de la optimización del proceso tecnológico para obtener citrato de calcio y magnesio a partir de dolomitas, se estudió a escala de banco la etapa de lavado para disminuir el contenido de ácido cítrico libre. Las variantes de lavado estudiadas permitieron disminuir el contenido de ácido cítrico libre por debajo del 3 %, mientras que los valores de calcio y magnesio son similares a los del lote antes de realizar el proceso de lavado. Por otro lado, el estudio toxicológico en ratas, comprobó que los lotes a los cuales se les aplicó las diferentes variantes de lavado no provocaron irritabilidad gástrica a las dosis de 2 000 mg/kg de peso corporal, por lo que se puede afirmar que el proceso de lavado establecido es adecuado para garantizar la calidad de la materia prima.As part of the technological process optomization to obtain calcium citrate and magnesium from dolomites, we studied at bench scale, the washout stage to decrease the free citric acid content. Washout variants allowed to decrease the free citric acid content under 3 %, whereas the calcium and magnesium values are similar to those of batch before to carry out the wahout process. On the other hand, toxicity study in rats, proved that the batches where different washout variables were applied not provoke gastric irritability at doses of 2 000 mg/kg of body weight confirming that above mentioned established process is approproate to guarantee the raw material quality.

  19. Acceptance of minerals and other compounds by calcium-deprived rats: 24-h tests.

    Science.gov (United States)

    Coldwell, S E; Tordoff, M G

    1996-07-01

    We measured 24-h spontaneous intake of four to eight concentrations of 31 different solutions by groups of rats fed control or low-calcium diets. Relative to controls, those fed low-calcium diet had increased acceptance of one or more concentrations of sodium chloride, sodium acetate, and sodium bicarbonate, but not sodium gluconate. Differences in palatability between these sodium salts were unimportant because the rats fed low-calcium diet consumed more sodium chloride even if this was made less acceptable by adulteration with citric acid. The possibility that calcium-deprived rats have an enhanced general cation or mineral appetite was supported by findings of increased acceptance of one or more concentrations of nine of ten chloride minerals tested (aluminum chloride, ammonium chloride, ferric chloride, ferrous chloride, magnesium chloride, sodium chloride, potassium chloride, strontium chloride, zinc chloride). However, there were no differences in acceptance of any concentration of cesium chloride, magnesium sulfate, or lead acetate. Moreover, calcium-deprived rats drank more hydrochloric acid and malic acid than did controls. Thus the effect of calcium deficiency on intake was not confined to minerals. Acidity or bitterness did not appear important because there was no difference between the groups in intake of sulfuric acid, citric acid, or quinine hydrochloride. Consistent with the exacerbating effects of phosphates on calcium deprivation, deprived rats had decreased intakes of phosphates (sodium phosphate, potassium phosphate). However, they also had decreased intakes of sucrose and saccharin. It is clear that calcium deprivation does not induce a general increase in acceptance of all taste solutions, but there appears to be no simple explanation for what these animals consume.

  20. Cell (patho)physiology of magnesium.

    Science.gov (United States)

    Wolf, Federica I; Trapani, Valentina

    2008-01-01

    There is an unsettled debate about the role of magnesium as a 'chronic regulator' of biological functions, as opposed to the well-known role for calcium as an 'acute regulator'. New and old findings appear to delineate an increasingly complex and important role for magnesium in many cellular functions. This review summarizes the available evidence for a link between the regulation of intracellular magnesium availability and the control of cell growth, energy metabolism and death, both in healthy and diseased conditions. A comprehensive view is precluded by technical difficulties in tracing magnesium within a multicompartment and dynamic environment like the cell; nevertheless, the last few years has witnessed encouraging progress towards a better characterization of magnesium transport and its storage or mobilization inside the cell. The latest findings pave the road towards a new and deeper appreciation of magnesium homoeostasis and its role in the regulation of essential cell functions.

  1. Production of magnesium metal

    Science.gov (United States)

    Blencoe, James G [Harriman, TN; Anovitz, Lawrence M [Knoxville, TN; Palmer, Donald A [Oliver Springs, TN; Beard, James S [Martinsville, VA

    2010-02-23

    A process of producing magnesium metal includes providing magnesium carbonate, and reacting the magnesium carbonate to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The carbon dioxide is used as a reactant in a second process. In another embodiment of the process, a magnesium silicate is reacted with a caustic material to produce magnesium hydroxide. The magnesium hydroxide is reacted with a source of carbon dioxide to produce magnesium carbonate. The magnesium carbonate is reacted to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The invention further relates to a process for production of magnesium metal or a magnesium compound where an external source of carbon dioxide is not used in any of the reactions of the process. The invention also relates to the magnesium metal produced by the processes described herein.

  2. Influence of sodium, calcium, magnesium, and ammonium in the sorption of cadmium in a zeolite rock; Influencia del sodio, calcio, magnesio y amonio en la sorcion de cadmio en una roca zeolitica

    Energy Technology Data Exchange (ETDEWEB)

    Teutli S, E.A

    2007-07-01

    The cadmium is one of the more toxic heavy metals and the water pollution by this metal, is originated by industries whose turn is the production of batteries, electroplating processes, the production of pigments and in the refinement process of others metals. The objective of this work was to evaluate the ion exchange of cadmium using natural zeolite, obtained from the Arroyo zone, La Haciendita Municipality, in the State of Chihuahua. The parameters considered in this investigation were: the sorption time, the pH, the initial concentration of cadmium and the influence of sodium, calcium, magnesium and ammonium on the sorption of cadmium in the natural zeolite. Also, the theoretical pattern for kinetics and isotherm that better it is adjusted to those experimental results it was determined. The experimentation results allowed to establish the following conclusions: the sorption of the cadmium doesn't depend on the pH in an interval between 4 and 6; the pattern that better it describes the kinetics it is that of Pseudo-second order of Ho and Mc Kay; the Langmuir-Freundlich pattern is the one that better it describes the sorption isotherm and the calcium is the component that interferes in an important manner in the sorption of cadmium. The carried out investigation contributes to the definition of some of the parameters that should be considered in the development of ion exchangers for the cadmium removal. (Author)

  3. [Magnesium for nutrient].

    Science.gov (United States)

    Kimura, Mieko

    2012-08-01

    Magnesium is essential nutrient. Here is magnesium for nutrient. Magnesium has a large number of biological or biochemical functions. It's distribution, absorption, deficiency, excess disorder, requirement, supply sources, and especially status and issue of magnesium intake in Japanese are reviewed.

  4. 21 CFR 181.29 - Stabilizers.

    Science.gov (United States)

    2010-04-01

    ...: Aluminum mono-, di-, and tristearate. Ammonium citrate. Ammonium potassium hydrogen phosphate. Calcium glycerophosphate. Calcium phosphate. Calcium hydrogen phosphate. Calcium oleate. Calcium acetate. Calcium carbonate. Calcium ricinoleate. Calcium stearate. Disodium hydrogen phosphate. Magnesium glycerophosphate. Magnesium...

  5. Simultaneous determination of free calcium, magnesium, sodium and potassium ion concentrations in simulated milk ultrafiltrate and reconstituted skim milk using the Donnan Membrane Technique

    NARCIS (Netherlands)

    Gao, R.; Temminghoff, E.J.M.; Leeuwen, van H.P.; Valenberg, van H.J.F.; Eisner, M.D.; Boekel, van M.A.J.S.

    2009-01-01

    This study focused on determination of free Ca2+, Mg2+, Na+ and K+ concentrations in a series of CaCl2 solutions, simulated milk ultrafiltrate and reconstituted skim milk using a recently developed Donnan Membrane Technique (DMT). A calcium ion selective electrode was used to compare the DMT

  6. Magnesium compounds

    Science.gov (United States)

    Kramer, D.A.

    2012-01-01

    Seawater and natural brines accounted for about 57 percent of magnesium compounds produced in the United States in 2011. Dead-burned magnesia was produced by Martin Marietta Magnesia Specialties LLC from well brines in Michigan. Caustic-calcined magnesia was recovered from seawater by Premier Magnesia LLC in Florida, from well brines in Michigan by Martin Marietta and from magnesite in Nevada by Premier Magnesia. Intrepid Potash Wendover LLC and Great Salt Lake Minerals Corp. recovered magnesium chloride brines from the Great Salt Lake in Utah. Magnesium hydroxide was produced from seawater by SPI Pharma Inc. in Delaware and Premier Magnesia in Florida, and by Martin Marietta from its brine operation in Michigan.

  7. Production of magnesium metal

    Energy Technology Data Exchange (ETDEWEB)

    Blencoe, James G [Harriman, TN; Anovitz, Lawrence M [Knoxville, TN; Palmer, Donald A [Oliver Springs, TN; Beard, James S [Martinsville, VA

    2012-04-10

    A process of producing magnesium metal includes providing magnesium carbonate, and reacting the magnesium carbonate to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The carbon dioxide is used as a reactant in a second process. In another embodiment of the process, a magnesium silicate is reacted with a caustic material to produce magnesium hydroxide. The magnesium hydroxide is reacted with a source of carbon dioxide to produce magnesium carbonate. The magnesium carbonate is reacted to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The invention also relates to the magnesium metal produced by the processes described herein.

  8. Determinação de cálcio e magnésio pelo EDTA em extratos ácidos de solos Calcium and magnesium determination in soils with EDTA

    Directory of Open Access Journals (Sweden)

    Bernardo van Raij

    1966-01-01

    Full Text Available Foi estudada marcha analítica para determinação de cálcio e magnésio, pelo EDTA, em soluções que continham também ferro, alumínio, manganês e cobre. Para extratos ácidos de solos, é proposta uma marcha analítica com as seguintes etapas: separação de ferro, alumínio e manganês, por precipitação em meio amoniacal, em presença de água oxigenada; titulação do cálcio com solução de EDTA a um pH maior que 12, empregando como indicador a murexida; destruição da murexida por acidificação e aquecimento; complexação do cobre com o dietilditiocarbamato de sódio e determinação do magnésio pela solução de EDTA, a pH 10, com o indicador preto de eriocromo T.A procedure for the determination of calcium and magnesium with EDTA in solutions containing iron, aluminum, manganese and copper was studied. The following procedure is proposed for 0.05 Nnitric acid extracts of soils: aprecipitation of iron, aluminum and manganese with ammonium hydroxide and hydrogen peroxide; bcalcium titration with EDTA solution at pH higher than 12, using murexide as dye; c destruction of the murexide by acidification and heating; dcopper complexing by sodium diethyldithyocarbamate and magnesium determination with EDTA, at pH 10, using Eriochrome Black T as dye.

  9. Paradoxical hypomagnesemia caused by excessive ingestion of magnesium hydroxide.

    Science.gov (United States)

    Joo Suk, Oh

    2008-09-01

    Excessive ingestion of magnesium may lead to hypermagnesemia even without kidney dysfunction. Several cases of development of hypermagnesemia after overdose of magnesium hydroxide have been reported. Although magnesium hydroxide is widely used as laxative, its overdose may induce diarrhea, which is followed by excessive magnesium loss. I report a case of paradoxical hypomagnesemia developed after excessive ingestion of magnesium hydroxide. A 39-year-old woman was presented to the emergency department complaining of severe watery diarrhea and carpopedal spasm after ingesting a handful of magnesium hydroxide tablets. The laboratory tests detected hypomagnesemia, hypocalcemia, and normokalemia. Calcium gluconate was given to the patient, but her symptom did not improve shortly. The symptom disappeared spontaneously 2 days after the watery diarrhea subsided. This case shows that overdose of magnesium hydroxide, which leads to massive diarrhea, might induce hypomagnesemia unexpectedly. This case also suggests that it should be treated, as well as typical magnesium deficiency.

  10. Andrographolide suppresses thymic stromal lymphopoietin in phorbol myristate acetate/calcium ionophore A23187-activated mast cells and 2,4-dinitrofluorobenzene-induced atopic dermatitis-like mice model

    Directory of Open Access Journals (Sweden)

    Li CX

    2016-02-01

    Full Text Available Chun-xiao Li,* Hua-guo Li,* Hui Zhang,* Ru-hong Cheng, Ming Li, Jian-ying Liang, Yan Gu, Bo Ling, Zhi-rong Yao, Hong Yu Department of Dermatology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China *These authors contributed equally to this work Background: Atopic dermatitis (AD is one of the most common inflammatory cutaneous diseases. Thymic stromal lymphopoietin (TSLP has been demonstrated to be an important immunologic factor in the pathogenesis of AD. The production of TSLP can be induced by a high level of intracellular calcium concentration and activation of the receptor-interacting protein 2/caspase-1/NF-κB pathway. Andrographolide (ANDRO, a natural bicyclic diterpenoid lactone, has been found to exert anti-inflammatory effects in gastrointestinal inflammatory disorders through suppressing the NF-κB pathway. Objective: To explore the effect of ANDRO on the production of TSLP in human mast cells and AD mice model. Methods: We utilized enzyme-linked immunosorbent assay, real-time reverse transcription polymerase chain reaction analysis, Western blot analysis, and immunofluorescence staining assay to investigate the effects of ANDRO on AD. Results: ANDRO ameliorated the increase in the intracellular calcium, protein, and messenger RNA levels of TSLP induced by phorbol myristate acetate/calcium ionophore A23187, through the blocking of the receptor-interacting protein 2/caspase-1/NF-κB pathway in human mast cell line 1 cells. ANDRO, via oral or local administration, also attenuated clinical symptoms in 2,4-dinitrofluorobenzene-induced AD mice model and suppressed the levels of TSLP in lesional skin. Conclusion: Taken together, ANDRO may be a potential therapeutic agent for AD through suppressing the expression of TSLP. Keywords: atopic dermatitis, thymic stromal lymphopoietin, andrographolide, human mast cell

  11. Bone repair in calcium-deficient rats: comparison of xylitol+calcium carbonate with calcium carbonate, calcium lactate and calcium citrate on the repletion of calcium.

    Science.gov (United States)

    Hämäläinen, M M

    1994-06-01

    The potential value of xylitol in calcium therapy was evaluated by comparing the effect of dietary xylitol (50 g/kg diet) + calcium carbonate with the effects of calcium carbonate, calcium lactate and calcium citrate on bone repair of young male rats after the rats consumed for 3 wk a calcium-deficient diet (0.2 g Ca/kg diet). After this calcium-depletion period, the rats were fed for 2 wk one of four diets, each containing 5 g Ca/kg diet as one of the four dietary calcium sources. The diet of the control animals was supplemented with CaCO3 (5 g Ca/kg diet) throughout the study. The Ca-deficient rats showed low bone mass, low serum calcium and high serum 1,25-dihydroxycholecalciferol, parathyroid hormone (1-34 fraction) and osteocalcin concentrations. They also excreted magnesium, phosphate and hydroxyproline in the urine in high concentrations, and had high bone alkaline phosphatase and tartrate-resistant acid phosphatase activities. Most of these changes were reversed by the administered of the calcium salts. The highest recoveries of femoral dry weight, calcium, magnesium and phosphate were observed in the groups receiving xylitol+CaCO3 and calcium lactate. Calcium lactate and calcium citrate caused low serum phosphate concentration compared with rats receiving CaCO3 and with the age-matched Ca-replete controls. Xylitol-treated rats excreted more calcium and magnesium in urine than did the other rats, probably due to increased absorption of these minerals from the gut. These results suggest that dietary xylitol improves the bioavailability of calcium salts.

  12. Relationship between macrofauna, mineralogy and exchangeable calcium and magnesium in Cerrado Oxisols under pasture Relações entre macrofauna, mineralogia, cálcio e magnésio trocáveis em Latossolos do Cerrado sob pastagem

    Directory of Open Access Journals (Sweden)

    Pedro Rodolfo Siqueira Vendrame

    2009-08-01

    Full Text Available The objective of this work was to assess the relationship between macrofauna, mineralogy and exchangeable calcium and magnesium in Cerrado Oxisols under pasture. Twelve collection points were chosen in the Distrito Federal and in Formosa municipality, Goiás state, Brazil, representing four soil groups with varied levels of calcium + magnesium and kaolinite/(kaolinite + gibbsite ratios. Soil macrofauna was collected in triplicate at each collection point, and identified at the level of taxonomic groups. Macrofauna density showed correlation with contents of kaolinite, gibbsite and exchangeable Ca + Mg in the soils. Mineralogy and exchangeable Ca + Mg had significant effects on taxonomic groups and relative density of soil macrofauna. The termites (Isoptera were more abundant in soils with low exchangeable Ca + Mg; earthworms (Oligochaeta, in soils with high levels of kaolinite; and Hemiptera and Coleoptera larvae were more abundant in gibbsitic soils with higher contents of total carbon.O objetivo deste trabalho foi avaliar as relações entre a macrofauna, a mineralogia e os teores de cálcio e magnésio, em latossolos do Cerrado sob pastagem. Doze pontos de coleta foram escolhidos no Distrito Federal e no Município de Formosa, GO, e representaram quatro grupos de solo com variados teores de cálcio + magnésio e razões caulinita/(caulinita + gibsita. A macrofauna do solo foi coletada em triplicata, em cada ponto, e identificada quanto ao grupo taxonômico. A densidade da macrofauna foi relacionada aos teores de caulinita, gibsita e Ca + Mg trocáveis. Houve efeito significativo da mineralogia e dos teores de Ca + Mg trocáveis sobre os grupos taxonômicos e sobre a densidade relativa da macrofauna edáfica. Verificou-se maior densidade de Isoptera nos solos com baixos teores de Ca + Mg, de Oligochaeta nos solos cauliníticos, e maior densidade de Hemiptera e larvas de Coleoptera nos solos gibsiticos e com maiores teores de carbono total.

  13. Effect of calcium and magnesium silicate on the growth of the castor oil plant subjected to salinity levels
    Efeito de silicato de cálcio e magnésio sobre o crescimento de plantas de mamoneira submetidas a níveis de salinidade

    OpenAIRE

    José Félix Brito Neto; Napoleão de Esberard Macêdo Beltrão; João Paulo Gonsiorkiewicz Rigon; Silvia Capuani

    2012-01-01

    Salt stress decreases the osmotic potential of soil solution causing water stress, causing toxic effects in the plants resulting in injuries on the metabolism and nutritional disorders, thus compromising the plant growth, resulting in lower production. The calcium silicate and magnesium can perform the same function as limestone, besides providing silicon to plants, may also contribute to the resistance of plants to salt stress. Thus, the objective of this study was to evaluate the effect of ...

  14. Magnesium compounds

    Science.gov (United States)

    Kramer, D.A.

    2007-01-01

    Seawater and natural brines accounted for about 52 percent of U.S. magnesium compounds production in 2006. Dead-burned magnesia was produced by Martin Marietta Magnesia Specialties from well brines in Michigan. Caustic-calcined magnesia was recovered from sea-water by Premier Chemicals in Florida; from well brines in Michigan by Martin Marietta and Rohm and Haas; and from magnesite in Nevada by Premier Chemicals. Intrepid Potash-Wendover and Great Salt Lake Minerals recovered magnesium chloride brines from the Great Salt Lake in Utah. Magnesium hydroxide was produced from brucite by Applied Chemical Magnesias in Texas, from seawater by SPI Pharma in Delaware and Premier Chemicals in Florida, and by Martin Marietta and Rohm and Haas from their operations mentioned above. About 59 percent of the magnesium compounds consumed in the United States was used for refractories that are used mainly to line steelmaking furnaces. The remaining 41 percent was consumed in agricultural, chemical, construction, environmental and industrial applications.

  15. Suboptimal magnesium status in the United States: are the health consequences underestimated?

    Science.gov (United States)

    Rosanoff, Andrea; Weaver, Connie M; Rude, Robert K

    2012-03-01

    In comparison with calcium, magnesium is an "orphan nutrient" that has been studied considerably less heavily. Low magnesium intakes and blood levels have been associated with type 2 diabetes, metabolic syndrome, elevated C-reactive protein, hypertension, atherosclerotic vascular disease, sudden cardiac death, osteoporosis, migraine headache, asthma, and colon cancer. Almost half (48%) of the US population consumed less than the required amount of magnesium from food in 2005-2006, and the figure was down from 56% in 2001-2002. Surveys conducted over 30 years indicate rising calcium-to-magnesium food-intake ratios among adults and the elderly in the United States, excluding intake from supplements, which favor calcium over magnesium. The prevalence and incidence of type 2 diabetes in the United States increased sharply between 1994 and 2001 as the ratio of calcium-to-magnesium intake from food rose from 3.0. Dietary Reference Intakes determined by balance studies may be misleading if subjects have chronic latent magnesium deficiency but are assumed to be healthy. Cellular magnesium deficit, perhaps involving TRPM6/7 channels, elicits calcium-activated inflammatory cascades independent of injury or pathogens. Refining the magnesium requirements and understanding how low magnesium status and rising calcium-to-magnesium ratios influence the incidence of type 2 diabetes, metabolic syndrome, osteoporosis, and other inflammation-related disorders are research priorities. © 2012 International Life Sciences Institute.

  16. Methanogenesis from acetate: enrichment studies.

    Science.gov (United States)

    Baresi, L; Mah, R A; Ward, D M; Kaplan, I R

    1978-01-01

    An acetate enrichment culture was initiated by inoculating anaerobic sludge from a mesophilic methane digestor into a mineral salts medium with calcium acetate as the sole carbon and energy source. This enrichment was maintained indefinitely by weekly transfer into medium of the same composition. A study of this enrichment disclosed an unexpected age-dependent inhibition of methanogenesis by H2 and formate which apparently differed from the inhibition by chloroform and benzyl viologen. This age-dependent inhibition indicated that microbial interactions of the mixed enrichment population may play a regulatory role in methane formation. Futhermore, stimulation of methanogenesis in the acetate enrichment by addition of yeast extract showed a nutrient limitation which indicated that syntrophic interactions leading to formation of growth factors may also occur. A model is presented to illustrate the possible interrelationships between methanogenic and nonmethanogenic bacteria in their growth and formation of methane and carbon dioxide from acetate. Images PMID:697356

  17. Mechanisms of mineral membrane fouling growth modulated by pulsed modes of current during electrodialysis: evidences of water splitting implications in the appearance of the amorphous phases of magnesium hydroxide and calcium carbonate.

    Science.gov (United States)

    Cifuentes-Araya, Nicolás; Astudillo-Castro, Carolina; Bazinet, Laurent

    2014-07-15

    Experiments revealed the fouling nature evolutions along different electrodialysis (ED) trials, and how it disappears when current pulsation acts repetitively on the interfaces of ion-exchange membranes (IEMs). Fouling was totally controlled on the diluate side of cation-exchange membrane (CEM) by the repetitive pulsation frequency of the higher on-duty ratios applied. They created steady water splitting proton-barriers that neutralized OH(-) leakage through the membrane, decreasing the interfacial pH, and fouling of the concentrate side. The anion-exchange membrane (AEM) on the diluate side was similarly protected, but it was fouled once water splitting OH(-) generation became either intense enough or excessively weak. Interestingly, amorphous magnesium hydroxide (AMH) stemmed on the CEM-diluate side from brucite under intense water splitting OH(-) generation, and/or strong OH(-) leakage electromigration through the membrane. Water dissociation and overlimiting current regimes triggered drastic water molecule removal from crystal lattices through an accelerated cascade water splitting reaction. Also, amorphous calcium carbonate (ACC) appeared on CEM under intense water splitting reaction, and disappeared once intense OH(-) leakage was allowed by the water splitting proton-barrier dissipation. Our findings have implications for membrane fouling control, as well as for the understanding of the growth behavior of CaCO3 and Mg(OH)2 species on electromembrane interfaces. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Insight into the local environment of magnesium and calcium in low-coordination-number organo-complexes using (25)Mg and (43)Ca solid-state NMR: a DFT study.

    Science.gov (United States)

    Gervais, Christel; Jones, Cameron; Bonhomme, Christian; Laurencin, Danielle

    2017-03-01

    With the increasing number of organocalcium and organomagnesium complexes under development, there is a real need to be able to characterize in detail their local environment in order to fully rationalize their reactivity. For crystalline structures, in cases when diffraction techniques are insufficient, additional local spectroscopies like (25)Mg and (43)Ca solid-state NMR may provide valuable information to help fully establish the local environment of the metal ions. In this current work, a prospective DFT investigation on crystalline magnesium and calcium complexes involving low-coordination numbers and N-bearing organic ligands was carried out, in which the (25)Mg and (43)Ca NMR parameters [isotropic chemical shift, chemical shift anisotropy (CSA) and quadrupolar parameters] were calculated for each structure. The analysis of the calculated parameters in relation to the local environment of the metal ions revealed that they are highly sensitive to very small changes in geometry/distances, and hence that they could be used to assist in the refinement of crystal structures. Moreover, such calculations provide a guideline as to how the NMR measurements will need to be performed, revealing that these will be very challenging.

  19. Impregnating Coal With Calcium Carbonate

    Science.gov (United States)

    Sharma, Pramod K.; Voecks, Gerald E.; Gavalas, George R.

    1991-01-01

    Relatively inexpensive process proposed for impregnating coal with calcium carbonate to increase rates of gasification and combustion of coal and to reduce emission of sulfur by trapping sulfur in calcium sulfide. Process involves aqueous-phase reactions between carbon dioxide (contained within pore network of coal) and calcium acetate. Coal impregnated with CO2 by exposing it to CO2 at high pressure.

  20. MAGNESIUM IN CLINICAL PRACTICE

    Directory of Open Access Journals (Sweden)

    E. L. Trisvetova

    2015-12-01

    Full Text Available Magnesium is a macronutrient that is needed for normal body functions. Magnesium deficiency resulting from the influence of exogenous and endogenous factors, is diagnosed by clinical manifestations, resembling the known disease. Magnesium deficiency corrected with the magnesium therapy. Studies show the effectiveness of magnesium orotate for many cardiovascular diseases.

  1. MAGNESIUM IN CLINICAL PRACTICE

    Directory of Open Access Journals (Sweden)

    E. L. Trisvetova

    2012-01-01

    Full Text Available Magnesium is a macronutrient that is needed for normal body functions. Magnesium deficiency resulting from the influence of exogenous and endogenous factors, is diagnosed by clinical manifestations, resembling the known disease. Magnesium deficiency corrected with the magnesium therapy. Studies show the effectiveness of magnesium orotate for many cardiovascular diseases.

  2. MAGNESIUM IN CLINICAL PRACTICE

    OpenAIRE

    E. L. Trisvetova

    2015-01-01

    Magnesium is a macronutrient that is needed for normal body functions. Magnesium deficiency resulting from the influence of exogenous and endogenous factors, is diagnosed by clinical manifestations, resembling the known disease. Magnesium deficiency corrected with the magnesium therapy. Studies show the effectiveness of magnesium orotate for many cardiovascular diseases.

  3. A Soft Coral Natural Product, 11-Episinulariolide Acetate, Inhibits Gene Expression of Cyclooxygenase-2 and Interleukin-8 through Attenuation of Calcium Signaling

    Directory of Open Access Journals (Sweden)

    Wei-Chiao Chang

    2013-06-01

    Full Text Available Epidermal growth factor receptor (EGFR is overexpressed in many types of cancer cells. EGFR-mediated signaling involves inflammatory gene expression including cyclooxygenase (COX-2 and interleukin (IL-8, and is associated with cancer pathogenesis. In a search of phytochemicals with anti-inflammatory activity, the COX-2 and IL-8 inhibitory activities of some marine compounds were examined. After screening these compounds 11-episinulariolide acetate (1 from soft coral exhibited the most potent activity. Reverse-transcription PCR; western blotting; ELISA and luciferase assays were used to test the effect of compound 1 on EGF-stimulated expressions of COX-2 and IL-8 in A431 human epidermoid carcinoma cells. After exposure to 10 μM of compound 1, expression levels of COX-2 and IL-8 were reduced. In addition; intracellular Ca2+ increase and Ca2+-dependent transcription factor activation were blocked by compound 1. Thus, compound 1 can potentially serve as a lead compound for targeting Ca2+ signaling-dependent inflammatory diseases.

  4. 75 FR 51002 - Pure Magnesium In Granular Form from the People's Republic of China: Initiation of Changed...

    Science.gov (United States)

    2010-08-18

    ... Import and Export/China National Nonferrous ] Metals Industry Trading Group Corp. (``Minmetals/CNNMIT... Magnesium Alloy''\\5\\ (generally referred to as ``off-specification pure'' magnesium); and (4) physical... aware used to make such excluded reagents are: lime, calcium metal, calcium silicon, calcium carbide...

  5. plasma magnesium in adult asthmatics at the lagos university

    African Journals Online (AJOL)

    hi-tech

    2003-09-09

    Sep 9, 2003 ... Objective: To determine the plasma magnesium levels in adult asthmatics. Design: Case control study. Setting: Lagos ... using spectrophotometric end point methods. Results: Mean (SD) plasma magnesium ... and it is known to have a direct effect on calcium uptake resulting in smooth muscle relaxation (3).

  6. The role of calbindin-D28k on renal calcium and magnesium handling during treatment with loop and thiazide diuretics.

    Science.gov (United States)

    Lee, Chien-Te; Ng, Hwee-Yeong; Lee, Yueh-Ting; Lai, Li-Wen; Lien, Yeong-Hau H

    2016-02-01

    Calbindin-D28k (CBD-28k) is a calcium binding protein located in the distal convoluted tubule (DCT) and plays an important role in active calcium transport in the kidney. Loop and thiazide diuretics affect renal Ca and Mg handling: both cause Mg wasting, but have opposite effects on Ca excretion as loop diuretics increase, but thiazides decrease, Ca excretion. To understand the role of CBD-28k in renal Ca and Mg handling in response to diuretics treatment, we investigated renal Ca and Mg excretion and gene expression of DCT Ca and Mg transport molecules in wild-type (WT) and CBD-28k knockout (KO) mice. Mice were treated with chlorothiazide (CTZ; 50 mg · kg(-1) · day(-1)) or furosemide (FSM; 30 mg · kg(-1) · day(-1)) for 3 days. To avoid volume depletion, salt was supplemented in the drinking water. Urine Ca excretion was reduced in WT, but not in KO mice, by CTZ. FSM induced similar hypercalciuria in both groups. DCT Ca transport molecules, including transient receptor potential vanilloid 5 (TRPV5), TRPV6, and CBD-9k, were upregulated by CTZ and FSM in WT, but not in KO mice. Urine Mg excretion was increased and transient receptor potential subfamily M, member 6 (TRPM6) was upregulated by both CTZ and FSM in WT and KO mice. In conclusion, CBD-28k plays an important role in gene expression of DCT Ca, but not Mg, transport molecules, which may be related to its being a Ca, but not a Mg, intracellular sensor. The lack of upregulation of DCT Ca transport molecules by thiazides in the KO mice indicates that the DCT Ca transport system is critical for Ca conservation by thiazides. Copyright © 2016 the American Physiological Society.

  7. Dolomite supplementation improves bone metabolism through modulation of calcium-regulating hormone secretion in ovariectomized rats.

    Science.gov (United States)

    Mizoguchi, Toshihide; Nagasawa, Sakae; Takahashi, Naoyuki; Yagasaki, Hiroshi; Ito, Michio

    2005-01-01

    Dolomite, a mineral composed of calcium magnesium carbonate (CaMg (CO3)2), is used as a food supplement that supplies calcium and magnesium. However, the effect of magnesium supplementation on bone metabolism in patients with osteoporosis is a matter of controversy. We examined the effects of daily supplementation with dolomite on calcium metabolism in ovariectomized (OVX) rats. Dolomite was administered daily to OVX rats for 9 weeks. The same amount of magnesium chloride as that supplied by the dolomite was given to OVX rats as a positive control. Histological examination revealed that ovariectomy decreased trabecular bone and increased adipose tissues in the femoral metaphysis. Dolomite or magnesium supplementation failed to improve these bone histological features. Calcium content in the femora was decreased in OVX rats. Neither calcium nor magnesium content in the femora in OVX rats was significantly increased by dolomite or magnesium administration. Urinary deoxypyridinoline excretion was significantly increased in OVX rats, and was not affected by the magnesium supplementation. Serum concentrations of magnesium were increased, and those of calcium were decreased, in OVX rats supplemented with dolomite or magnesium. However, there was a tendency toward decreased parathyroid hormone secretion and increased calcitonin secretion in OVX rats supplemented with dolomite or magnesium. Serum 1,25-dihydroxyvitamin D(3) and osteocalcin levels were significantly increased in the supplemented OVX rats. These results suggest that increased magnesium intake improves calcium metabolism in favor of increasing bone formation, through the modulation of calcium-regulating hormone secretion.

  8. First-principles studies on alloying and simplified thermodynamic aqueous chemical stability of calcium-, zinc-, aluminum-, yttrium- and iron-doped magnesium alloys.

    Science.gov (United States)

    Velikokhatnyi, Oleg I; Kumta, Prashant N

    2010-05-01

    In the present study, the density functional theory implemented in the Vienna Ab-initio Simulation Package has been used to investigate the alloying effects of different elements of calcium, zinc, yttrium, aluminum and iron when introduced in the Mg crystal lattice. In particular, studies have been conducted to investigate the thermodynamics of the overall hydrolysis reaction of the different alloys with pure water. Phase stability results obtained from the first-principles calculations of the alloys considered are in good agreement with the published phase diagrams. The heats of the aqueous chemical reactions calculated in this study have been compared with that corresponding to the reaction of pure Mg with water. The heats of reactions dependence on the chemical compositions of the alloys have been investigated and, specifically, the role of Ca, Zn, Y, Al and Fe on the aqueous chemical stability and reactivity of these Mg alloys have been discussed. Results of these studies will help understand the biodegradable characteristic of Mg based alloys. Copyright (c) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  9. Response of Chlorophyll, Relative Water Content and Protein Percentage of Safflower Leaves to Salinity and Foliar Calcium, Potassium and Magnesium Applications

    Directory of Open Access Journals (Sweden)

    Mahmood Attarzadeh

    2016-03-01

    Full Text Available To study the effect of Ca, K, and Mn foliar spray on chlorophyll and relative water contents of safflower (cv. Padideh leaves under salinity condition a factorial experiment based on randomized complete block design with three replications was conducted at Vali-e-Asr University Greenhouse in 2011. Factors were salinity with four levels: 0, 500, 1000, and 1500 mg NaCl kg -1, and foliar spraying of plants with four levels: distilled water, 10 mM CaNo3, 10 mM K2HPO4 and 1 mM MnSo4. Spraying were applied two weeks after emergence and continued every 2 weeks. Results showed that 1500 mg NaCl reduced SPAD value, leaf chlorophyll fluorescence and relative water content. However, increasing salinity induced higher leaf water saturation. Foliar spraying of plants with MnSO4, K2HPO4 and CaNo3 nutrients, also reduced SPAD value. Foliar application of plants with Ca(NO32 increased leaf protein in 500 mg NaCl and without salinity. Application of MnSo4 increased chlorophyll b, a+b and also chlorophyll a (in 500 mg NaCl. Thus, in respect to the positive role of calcium and manganese in the production and preservation of chlorophyll and protein, foliar spray application can be a suitable strategy to reduce crop losses under salinity conditions.

  10. Influência da diferença cátion-aniônica da dieta sobre o balanço de cálcio, fósforo e magnésio em ovinos Influence of the dietary cation-anion difference on calcium, phosphorus and magnesium balance in sheep

    Directory of Open Access Journals (Sweden)

    C.A. Gomide

    2004-06-01

    Full Text Available O efeito do balanço cátion-aniônico da dieta (BCAD no balanço macromineral (cálcio, fósforo e magnésio, no pH urinário e fecal, na concentração sérica de cálcio, fósforo e magnésio foi estudado utilizando-se 16 carneiros machos, da raça Santa Inês, por um período de 26 dias, sendo sete de adaptação. O delineamento experimental foi em blocos ao acaso, com quatro tratamentos. Para a manipulação do BCAD foram adicionados cloreto de cálcio e bicarbonato de sódio, obtendo-se os seguintes tratamentos: -12; +30; +76 e +133mEq/kg MS da ração. Não foram encontradas diferenças (P>0,10 no pH fecal, pH urinário, balanço de fósforo e magnésio. Com o aumento do BCAD houve decréscimo da absorção e retenção de cálcio, e aumento da excreção fecal. A manipulação do BCAD interferiu no metabolismo de macrominerais, principalmente no de cálcio.The dietary cation-anion balance (DCAB effect on the macromineral (calcium, phosphorus and magnesium balance, urinary and faecal pH, serum concentration of calcium, phosphorus and magnesium was studied in 16 Santa Inês adult sheep, during 26 days, being a seven-day-period of adaptation. The experiment consisted in a completely randomized block design with four treatments. Calcium chloride and sodium bicarbonate were added to DCAB manipulations to achieve the values: -12; + 30; +76 and +133mEq/kg DM. There was no effect of DCAB (P>0.10 on fecal and urinary pH, and on phosphorus and magnesium balance. The increase in the DCAB corresponded to a decrease in calcium absorption and calcium retention, and an increase in calcium fecal excretion values. The manipulation of the DCAB affected the macromineral metabolism, mainly the calcium metabolism.

  11. Cokrigagem na estimativa dos teores de Ca e Mg em um Latossolo Vermelho distroférrico Cokriging to estimate levels of calcium and magnesium in a Rhodic Hapludox

    Directory of Open Access Journals (Sweden)

    Eduardo Leonel Bottega

    2011-12-01

    Full Text Available Buscou-se, com este estudo, estimar, através do uso da cokrigagem, valores de cálcio e magnésio, utilizando como co-variável valores de pH. Em um Latossolo Vermelho Distroférrico, amostrou-se a camada de 0-0,2 m, utilizando grade de 25 x 25 m, totalizando 60 pontos em 5,02 ha. Realizou-se, inicialmente, análise descritiva e de correlação e, posteriormente, análise geoestatística, para identificar a dependência espacial das variáveis estudadas. Utilizando a técnica da cokrigagem, os valores de pH mostraram-se eficientes na estimativa de teores de Ca e Mg, devido a elevada correlação entre esta co-variável e as variáveis a serem estimadas.Sought, with this study, estimating, through the use of cokriging, values of calcium and magnesium, using as covariate pH. In a Rhodic Hapludox, sampled the layer of 0-0.2 m, using the grid of 25 x 25 m, totaling 60 points from 5.02 ha. Was held, initially, descriptive analysis and correlation, and subsequently, geostatistical analysis to identify the spatial dependence of variables. Using the technique of cokriging pH values were efficient in the estimation of Ca and Mg, due to the high correlation between this covariate and the variables to be estimated.

  12. Magnesium: Nutrition and Homoeostasis

    Directory of Open Access Journals (Sweden)

    Jürgen Vormann

    2016-05-01

    Full Text Available The essential mineral magnesium is involved in numerous physiological processes. Recommended dietary intake is often not met and a low magnesium status increases the risk for various diseases. Magnesium status is regulated by several magnesium transport systems either in cellular or paracellular pathways. Numerous drugs either interfere with magnesium absorption in the intestines or the reabsorption from primary urine in the kidney. Low magnesium status has been identified as a significant risk factor for several diseases, including type-2 diabetes, cardiovascular diseases, arrhythmias, as well as general muscular and neurological problems. Therefore, an adequate magnesium supply would be of special benefit to our overall health.

  13. Magnesium degradation products: effects on tissue and human metabolism.

    Science.gov (United States)

    Seitz, J-M; Eifler, R; Bach, Fr-W; Maier, H J

    2014-10-01

    Owing to their mechanical properties, metallic materials present a promising solution in the field of resorbable implants. The magnesium metabolism in humans differs depending on its introduction. The natural, oral administration of magnesium via, for example, food, essentially leads to an intracellular enrichment of Mg(2+) . In contrast, introducing magnesium-rich substances or implants into the tissue results in a different decomposition behavior. Here, exposing magnesium to artificial body electrolytes resulted in the formation of the following products: magnesium hydroxide, magnesium oxide, and magnesium chloride, as well as calcium and magnesium apatites. Moreover, it can be assumed that Mg(2+) , OH(-) ions, and gaseous hydrogen are also present and result from the reaction for magnesium in an aqueous environment. With the aid of physiological metabolic processes, the organism succeeds in either excreting the above mentioned products or integrating them into the natural metabolic process. Only a burst release of these products is to be considered a problem. A multitude of general tissue effects and responses from the Mg's degradation products is considered within this review, which is not targeting specific implant classes. Furthermore, common alloying elements of magnesium and their hazardous potential in vivo are taken into account. © 2013 Wiley Periodicals, Inc.

  14. Chemically prepared lead magnesium niobate dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Tuttle, B.A.; Voigt, J.A.; Sipola, D.L.; Olson, W.R.; Goy, D.M.

    1998-11-01

    A chemical solution powder synthesis technique has been developed that produces first, uniform powders of lead magnesium niobate (PMN) with 60 to 80 nm crystallite size. The synthesis technique was based on the dissolution of lead acetate and alkoxide precursors in acetic acid followed by precipitation with oxalic acid/propanol solutions. Lead magnesium niobate ceramics fabricated from these chemically derived powders had smaller, more uniform grain size and higher dielectric constants than ceramics fabricated from mixed oxide powders that were processed under similar thermal conditions. Chem-prep PMN dielectrics with peak dielectric constants greater than 22,000 and polarizations in excess of 29 {micro}C/cm{sup 2} were obtained for 1,100 C firing treatments. Substantial decreases in dielectric constant and polarization were measured for chemically prepared PMN ceramics fired at lower temperatures, consistent with previous work on mixed oxide materials.

  15. Dual effect of magnesium on compound 48/80-induced histamine secretion from rat peritoneal mast cells

    DEFF Research Database (Denmark)

    Bertelsen, Niels Haldor; Johansen, Torben

    1991-01-01

    The effect of magnesium on the secretory response to compound 48/80 from rat peritoneal mast cells was studied. The decrease in secretion caused by calcium deprivation was enlarged by magnesium. Glucose partially counteracted the decrease caused by calcium deprivation but not the one caused...... by magnesium. The addition of calcium to the cells simultaneously with compound 48/80 completely restored the secretory response if magnesium was present. The response was only partially restored in a magnesium- and glucose-free medium, whereas it was almost completely restored if glucose was present....... Magnesium had a considerable effect on the restoration of the secretory response of EGTA-treated cells, whereas the effect of glucose was minimal indicating that an effect on the energy metabolism was of minor importance. The secretory response could also be restored by an exposure of the cells to calcium...

  16. DISTILLATION OF CALCIUM

    Science.gov (United States)

    Barton, J.

    1954-07-27

    This invention relates to an improvement in the process for the purification of caicium or magnesium containing an alkali metal as impurity, which comprises distiiling a batch of the mixture in two stages, the first stage distillation being carried out in the presence of an inert gas at an absolute pressure substantially greater than the vapor pressure of calcium or maguesium at the temperature of distillation, but less than the vaper pressure at that temperature of the alkali metal impurity so that only the alkali metal is vaporized and condensed on a condensing surface. A second stage distilso that substantially only the calcium or magnesium distills under its own vapor pressure only and condenses in solid form on a lower condensing surface.

  17. Choline Magnesium Trisalicylate

    Science.gov (United States)

    Choline magnesium trisalicylate is used to relieve the pain, tenderness, inflammation (swelling), and stiffness caused by arthritis and painful ... used to relieve pain and lower fever. Choline magnesium trisalicylate is in a class of nonsteroidal anti- ...

  18. Low magnesium level

    Science.gov (United States)

    ... low magnesium may develop. Common causes of low magnesium include: Alcohol use Burns that affect a large area of the body Chronic diarrhea Excessive urination (polyuria), such as in uncontrolled diabetes and during recovery from acute kidney failure High ...

  19. Magnesium and Space Flight

    Science.gov (United States)

    Smith, Scott M.; Zwart, Sara R.

    2015-01-01

    Magnesium is an essential nutrient for muscle, cardiovascular, and bone health on Earth, and during space flight. We sought to evaluate magnesium status in 43 astronauts (34 male, 9 female; 47 ± 5 years old, mean ± SD) before, during, and after 4–6-month space missions. We also studied individuals participating in a ground analog of space flight (head-down-tilt bed rest; n = 27 (17 male, 10 female), 35 ± 7 years old). We evaluated serum concentration and 24-h urinary excretion of magnesium, along with estimates of tissue magnesium status from sublingual cells. Serum magnesium increased late in flight, while urinary magnesium excretion was higher over the course of 180-day space missions. Urinary magnesium increased during flight but decreased significantly at landing. Neither serum nor urinary magnesium changed during bed rest. For flight and bed rest, significant correlations existed between the area under the curve of serum and urinary magnesium and the change in total body bone mineral content. Tissue magnesium concentration was unchanged after flight and bed rest. Increased excretion of magnesium is likely partially from bone and partially from diet, but importantly, it does not come at the expense of muscle tissue stores. While further study is needed to better understand the implications of these findings for longer space exploration missions, magnesium homeostasis and tissue status seem well maintained during 4–6-month space missions. PMID:26670248

  20. Magnesium and Space Flight

    Directory of Open Access Journals (Sweden)

    Scott M. Smith

    2015-12-01

    Full Text Available Magnesium is an essential nutrient for muscle, cardiovascular, and bone health on Earth, and during space flight. We sought to evaluate magnesium status in 43 astronauts (34 male, 9 female; 47 ± 5 years old, mean ± SD before, during, and after 4–6-month space missions. We also studied individuals participating in a ground analog of space flight (head-down-tilt bed rest; n = 27 (17 male, 10 female, 35 ± 7 years old. We evaluated serum concentration and 24-h urinary excretion of magnesium, along with estimates of tissue magnesium status from sublingual cells. Serum magnesium increased late in flight, while urinary magnesium excretion was higher over the course of 180-day space missions. Urinary magnesium increased during flight but decreased significantly at landing. Neither serum nor urinary magnesium changed during bed rest. For flight and bed rest, significant correlations existed between the area under the curve of serum and urinary magnesium and the change in total body bone mineral content. Tissue magnesium concentration was unchanged after flight and bed rest. Increased excretion of magnesium is likely partially from bone and partially from diet, but importantly, it does not come at the expense of muscle tissue stores. While further study is needed to better understand the implications of these findings for longer space exploration missions, magnesium homeostasis and tissue status seem well maintained during 4–6-month space missions.

  1. Magnesium in diet

    Science.gov (United States)

    ... Magnesium is an essential mineral for human nutrition. Function Magnesium is needed for more than 300 biochemical reactions ... It helps to maintain normal nerve and muscle function, supports a healthy ... the role of magnesium in preventing and managing disorders such as high ...

  2. Role of magnesium in alleviation of aluminium toxicity in plants.

    Science.gov (United States)

    Bose, Jayakumar; Babourina, Olga; Rengel, Zed

    2011-04-01

    Magnesium is pivotal for activating a large number of enzymes; hence, magnesium plays an important role in numerous physiological and biochemical processes affecting plant growth and development. Magnesium can also ameliorate aluminium phytotoxicity, but literature reports on the dynamics of magnesium homeostasis upon exposure to aluminium are rare. Herein existing knowledge on the magnesium transport mechanisms and homeostasis maintenance in plant cells is critically reviewed. Even though overexpression of magnesium transporters can alleviate aluminium toxicity in plants, the mechanisms governing such alleviation remain obscure. Possible magnesium-dependent mechanisms include (i) better carbon partitioning from shoots to roots; (ii) increased synthesis and exudation of organic acid anions; (iii) enhanced acid phosphatase activity; (iv) maintenance of proton-ATPase activity and cytoplasmic pH regulation; (v) protection against an aluminium-induced cytosolic calcium increase; and (vi) protection against reactive oxygen species. Future research should concentrate on assessing aluminium toxicity and tolerance in plants with overexpressed or antisense magnesium transporters to increase understanding of the aluminium-magnesium interaction.

  3. Intradermal administration of magnesium sulphate and magnesium chloride produces hypesthesia to mechanical but hyperalgesia to heat stimuli in humans

    Directory of Open Access Journals (Sweden)

    Ikemoto Tatsunori

    2009-08-01

    Full Text Available Abstract Background Although magnesium ions (Mg2+ are known to display many similar features to other 2+ charged cations, they seem to have quite an important and unique role in biological settings, such as NMDA blocking effect. However, the role of Mg2+ in the neural transmission system has not been studied as sufficiently as calcium ions (Ca2+. To clarify the sensory effects of Mg2+ in peripheral nervous systems, sensory changes after intradermal injection of Mg2+ were studied in humans. Methods Magnesium sulphate, magnesium chloride and saline were injected into the skin of the anterior region of forearms in healthy volunteers and injection-induced irritating pain ("irritating pain", for short, tactile sensation, tactile pressure thresholds, pinch-pain changes and intolerable heat pain thresholds of the lesion were monitored. Results Flare formation was observed immediately after magnesium sulphate or magnesium chloride injection. We found that intradermal injections of magnesium sulphate and magnesium chloride transiently caused irritating pain, hypesthesia to noxious and innocuous mechanical stimulations, whereas secondary hyperalgesia due to mechanical stimuli was not observed. In contrast to mechanical stimuli, intolerable heat pain-evoking temperature was significantly decreased at the injection site. In addition to these results, spontaneous pain was immediately attenuated by local cooling. Conclusion Membrane-stabilizing effect and peripheral NMDA-blocking effect possibly produced magnesium-induced mechanical hypesthesia, and extracellular cation-induced sensitization of TRPV1 channels was thought to be the primary mechanism of magnesium-induced heat hyperalgesia.

  4. Magnesium Metabolism and its Disorders

    OpenAIRE

    Swaminathan, R.

    2003-01-01

    Magnesium is the fourth most abundant cation in the body and plays an important physiological role in many of its functions. Magnesium balance is maintained by renal regulation of magnesium reabsorption. The exact mechanism of the renal regulation is not fully understood. Magnesium deficiency is a common problem in hospital patients, with a prevalence of about 10%. There are no readily available and easy methods to assess magnesium status. Serum magnesium and the magnesium tolerance test are ...

  5. Magnesium as a biodegradable and bioabsorbable material for medical implants

    Science.gov (United States)

    Brar, Harpreet S.; Platt, Manu O.; Sarntinoranont, Malisa; Martin, Peter I.; Manuel, Michele V.

    2009-09-01

    For many years, stainless steel, cobalt-chromium, and titanium alloys have been the primary biomaterials used for load-bearing applications. However, as the need for structural materials in temporary implant applications has grown, materials that provide short-term structural support and can be reabsorbed into the body after healing are being sought. Since traditional metallic biomaterials are typically biocompatible but not biodegradable, the potential for magnesium-based alloys in biomedical applications has gained more interest. This paper summarizes the history and current status of magnesium as a bioabsorbable implant material. Also discussed is the development of a magnesium-zinc-calcium alloy that demonstrates promising degradation behavior.

  6. Magnesium Counteracts Vascular Calcification: Passive Interference or Active Modulation?

    Science.gov (United States)

    Ter Braake, Anique D; Shanahan, Catherine M; de Baaij, Jeroen H F

    2017-08-01

    Over the last decade, an increasing number of studies report a close relationship between serum magnesium concentration and cardiovascular disease risk in the general population. In end-stage renal disease, an association was found between serum magnesium and survival. Hypomagnesemia was identified as a strong predictor for cardiovascular disease in these patients. A substantial body of in vitro and in vivo studies has identified a protective role for magnesium in vascular calcification. However, the precise mechanisms and its contribution to cardiovascular protection remain unclear. There are currently 2 leading hypotheses: first, magnesium may bind phosphate and delay calcium phosphate crystal growth in the circulation, thereby passively interfering with calcium phosphate deposition in the vessel wall. Second, magnesium may regulate vascular smooth muscle cell transdifferentiation toward an osteogenic phenotype by active cellular modulation of factors associated with calcification. Here, the data supporting these major hypotheses are reviewed. The literature supports both a passive inorganic phosphate-buffering role reducing hydroxyapatite formation and an active cell-mediated role, directly targeting vascular smooth muscle transdifferentiation. However, current evidence relies on basic experimental designs that are often insufficient to delineate the underlying mechanisms. The field requires more advanced experimental design, including determination of intracellular magnesium concentrations and the identification of the molecular players that regulate magnesium concentrations in vascular smooth muscle cells. © 2017 American Heart Association, Inc.

  7. Magnesium in disease

    Science.gov (United States)

    Wanner, Christoph

    2012-01-01

    Although the following text will focus on magnesium in disease, its role in healthy subjects during physical exercise when used as a supplement to enhance performance is also noteworthy. Low serum magnesium levels are associated with metabolic syndrome, Type 2 diabetes mellitus (T2DM) and hypertension; consequently, some individuals benefit from magnesium supplementation: increasing magnesium consumption appears to prevent high blood pressure, and higher serum magnesium levels are associated with a lower risk of developing a metabolic syndrome. There are, however, conflicting study results regarding magnesium administration with myocardial infarction with and without reperfusion therapy. There was a long controversy as to whether or not magnesium should be given as a first-line medication. As the most recent trials have not shown any difference in outcome, intravenous magnesium cannot be recommended in patients with myocardial infarction today. However, magnesium has its indication in patients with torsade de pointes and has been given successfully to patients with digoxin-induced arrhythmia or life-threatening ventricular arrhythmias. Magnesium sulphate as an intravenous infusion also has an important established therapeutic role in pregnant women with pre-eclampsia as it decreases the risk of eclamptic seizures by half compared with placebo. PMID:26069818

  8. Calcium - urine

    Science.gov (United States)

    Urinary Ca+2; Kidney stones - calcium in urine; Renal calculi - calcium in your urine; Parathyroid - calcium in urine ... Urine calcium level can help your provider: Decide on the best treatment for the most common type of kidney ...

  9. Extraction of Al and Na from red mud by magnesium oxide sodium ...

    African Journals Online (AJOL)

    AJL

    produce an insoluble dimagnesium silicate, magnesium ferrite, magnesium titanate and a soluble sodium aluminate. A variation of the red mud ... carbonate, reacts with Fe2O3 and forms sodium ferrite as. *Corresponding author. E-mail: Id- ..... Lime Sinter with Calcium: Silica ratio::1, Comalco,. RTS Technical Note: 9392.

  10. Obtaining of inulin acetate

    OpenAIRE

    Khusenov, Arslonnazar; Rakhmanberdiev, Gappar; Rakhimov, Dilshod; Khalikov, Muzaffar

    2014-01-01

    In the article first obtained inulin ester inulin acetate, by etherification of inulin with acetic anhydride has been exposed. Obtained product has been studied using elementary analysis and IR spectroscopy.

  11. Magnesium in pregnancy.

    Science.gov (United States)

    Dalton, Lynne M; Ní Fhloinn, Deirdre M; Gaydadzhieva, Gergana T; Mazurkiewicz, Ola M; Leeson, Heather; Wright, Ciara P

    2016-09-01

    Magnesium deficiency is prevalent in women of childbearing age in both developing and developed countries. The need for magnesium increases during pregnancy, and the majority of pregnant women likely do not meet this increased need. Magnesium deficiency or insufficiency during pregnancy may pose a health risk for both the mother and the newborn, with implications that may extend into adulthood of the offspring. The measurement of serum magnesium is the most widely used method for determining magnesium levels, but it has significant limitations that have both hindered the assessment of deficiency and affected the reliability of studies in pregnant women. Thus far, limited studies have suggested links between magnesium inadequacy and certain conditions in pregnancy associated with high mortality and morbidity, such as gestational diabetes, preterm labor, preeclampsia, and small for gestational age or intrauterine growth restriction. This review provides recommendations for further study and improved testing using measurement of red cell magnesium. Pregnant women should be counseled to increase their intake of magnesium-rich foods such as nuts, seeds, beans, and leafy greens and/or to supplement with magnesium at a safe level. © The Author(s) 2016. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. Therapeutic uses of magnesium.

    Science.gov (United States)

    Guerrera, Mary P; Volpe, Stella Lucia; Mao, Jun James

    2009-07-15

    Magnesium is an essential mineral for optimal metabolic function. Research has shown that the mineral content of magnesium in food sources is declining, and that magnesium depletion has been detected in persons with some chronic diseases. This has led to an increased awareness of proper magnesium intake and its potential therapeutic role in a number of medical conditions. Studies have shown the effectiveness of magnesium in eclampsia and preeclampsia, arrhythmia, severe asthma, and migraine. Other areas that have shown promising results include lowering the risk of metabolic syndrome, improving glucose and insulin metabolism, relieving symptoms of dysmenorrhea, and alleviating leg cramps in women who are pregnant. The use of magnesium for constipation and dyspepsia are accepted as standard care despite limited evidence. Although it is safe in selected patients at appropriate dosages, magnesium may cause adverse effects or death at high dosages. Because magnesium is excreted renally, it should be used with caution in patients with kidney disease. Food sources of magnesium include green leafy vegetables, nuts, legumes, and whole grains.

  13. Physical and chemical properties of fish and chicken bones as calcium source for mineral supplements

    Directory of Open Access Journals (Sweden)

    Worapot Suntornsuk

    2006-03-01

    Full Text Available Physical and chemical properties of two bones of two species of fish, hoki (Macruronus novaezelandiae and giant seaperch (Lates calcarifer Bloch., were compared with chicken bone to evaluate their composition for use as natural calcium supplement. The information could be useful for waste utilization in the food and pharmaceutical industries. Physical testing and chemical analyses were performed according to the USP 24 and BP 1998 standards under calcium carbonate monograph. Loss on drying found in hoki, giant seaperch and chicken bones was 12.4, 11.3 and 5.9 % w/w, calculated on dried basis, respectively. Total calcium determined by complexometric titration was 31.8, 28.1 and 32.2% w/w in hoki, giant seaperch and chicken bones, respectively. All samples contained carbonate and phosphate anion residues but gluconate, acetate and citrate were absent. The presence of calcium carbonate was confirmed by thermogravimetry. Results from all bones showed that limit tests for heavy metals, arsenic and iron complied with the USP standard, whereas barium, chloride and sulfate conformed to the BP standard. The magnesium and alkali metals in giant seaperch bone were within the BP limit (1.5%, but those of hoki and chicken bone exceeded the limit.

  14. Interactions between magnesium, calcium, and aluminum on soybean root elongation Interação entre magnésio, cálcio e alumínio na elongação radicular da soja

    Directory of Open Access Journals (Sweden)

    Ivo Ribeiro da Silva

    2005-10-01

    Full Text Available Alleviation of Al rhizotoxicity by Ca and Mg can differ among species and genotypes. Root elongation of soybean [Glycine max (L. Merr.] line N93-S-179 and cvs. Young and Ransom exposed to varying concentrations of Al, Ca and Mg were compared in two experiments using a vertically split root system. Roots extending from a surface compartment with limed soil grew for 12 days into a subsurface compartment with nutrient solution treatments maintained at pH 4.6 with either 0 or 15 µmol L-1 Al. Calcium and Mg concentrations in treatments ranging from 0 to 20 mmol L-1. Although an adequate supply of Mg was provided in the surface soil compartment for soybean top growth, an inclusion of Mg was necessary in the subsurface solutions to promote root elongation in both the presence and absence of Al. In the absence of Al in the subsurface solution, tap root length increased by 74 % and lateral root length tripled when Mg in the solutions was increased from 0 to either 2 or 10 mmol L-1. In the presence of 15 µmol L-1 Al, additions of 2 or 10 mmol L-1 Mg increased tap root length fourfold and lateral root length by a factor of 65. This high efficacy of Mg may have masked differences in Al tolerance between genotypes N93 and Young. Magnesium was more effective than Ca in alleviating Al rhizotoxicity, and its ameliorative properties could not be accounted for by estimated electrostatic changes in root membrane potential and Al3+ activity at the root surface. The physiological mechanisms of Mg alleviation of Al injury in roots, however, are not known.A redução na rizotoxidez de Al por Ca e Mg difere entre espécies e genótipos. A elongação radicular da linhagem N93-S-179 e cvs. Young e Ransom de soja [Glycine max (L. Merr.] exposta a concentrações variáveis de Al, Ca e Mg foi comparada em dois experimentos, usando um sistema de raízes subdivididas verticalmente. As raízes cresceram por 12 dias a partir de um compartimento superficial com solo

  15. Nutrition and magnesium absorption

    NARCIS (Netherlands)

    Brink, E.J.

    1992-01-01

    The influence of various nutrients present in dairy products and soybean-based products on absorption of magnesium has been investigated. The studies demonstrate that soybean protein versus casein lowers apparent magnesium absorption in rats through its phytate component. However, true

  16. Magnesium in subarachnoid hemorrhage

    NARCIS (Netherlands)

    Bergh, W.M. (Walter Marcel) van den

    2004-01-01

    The main objective of this thesis was to determine the role of serum magnesium in the pathophysiology after subarachnoid hemorrhage (SAH) and to assess the effect of magnesium treatment in reducing cerebral ischemia in experimental SAH and in improving clinical outcome in patients with

  17. Magnesium for Hydrogen Storage

    DEFF Research Database (Denmark)

    Vigeholm, B.; Kjøller, John; Larsen, Bent

    1980-01-01

    The reaction of hydrogen with commercially pure magnesium powder (above 99.7%) was investigated in the temperature range 250–400 °C. Hydrogen is readily sorbed above the dissociation pressure. During the initial exposure the magnesium powder sorbs hydrogen slowly below 400 °C but during the second...

  18. Pallidol hexa-acetate ethyl acetate monosolvate.

    Science.gov (United States)

    Mao, Qinyong; Taylor, Dennis K; Ng, Seik Weng; Tiekink, Edward R T

    2013-01-01

    The entire mol-ecule of pallidol hexa-acetate {systematic name: (±)-(4bR,5R,9bR,10R)-5,10-bis-[4-(acet-yloxy)phen-yl]-4b,5,9b,10-tetra-hydro-indeno-[2,1-a]indene-1,3,6,8-tetrayl tetra-acetate} is completed by the application of twofold rotational symmetry in the title ethyl acetate solvate, C40H34O12·C4H8O2. The ethyl acetate mol-ecule was highly disordered and was treated with the SQUEEZE routine [Spek (2009 ▶). Acta Cryst. D65, 148-155]; the crystallographic data take into account the presence of the solvent. In pallidol hexa-acetate, the dihedral angle between the fused five-membered rings (r.m.s. deviation = 0.100 Å) is 54.73 (6)°, indicating a significant fold in the mol-ecule. Significant twists between residues are also evident as seen in the dihedral angle of 80.70 (5)° between the five-membered ring and the pendent benzene ring to which it is attached. Similarly, the acetate residues are twisted with respect to the benzene ring to which they are attached [C-O(carb-oxy)-C-C torsion angles = -70.24 (14), -114.43 (10) and -72.54 (13)°]. In the crystal, a three-dimensional architecture is sustained by C-H⋯O inter-actions which encompass channels in which the disordered ethyl acetate mol-ecules reside.

  19. Isolation, characterization and optimization of indigenous acetic acid bacteria and evaluation of their preservation methods

    OpenAIRE

    Sharafi, SM; Rasooli, I; Beheshti-Maal, K

    2010-01-01

    Background and Objectives Acetic acid bacteria (AAB) are useful in industrial production of vinegar. The present study aims at isolation and identification of acetic acid bacteria with characterization, optimization, and evaluation of their acetic acid productivity. Materials and Methods Samples from various fruits were screened for presence of acetic acid bacteria on glucose, yeast extract, calcium carbonate (GYC) medium. Carr medium supplemented with bromocresol green was used for distingui...

  20. The reference range of serum magnesium substance concentration ...

    African Journals Online (AJOL)

    Background: Magnesium is the second most abundant intracellular cation, with only a small proportion of the body's content being in the extracellular fluid. It is required for the active transport of other cations such as calcium, sodium and potassium across the membrane by active transport system. It is also needed for many ...

  1. Magnesium and depression.

    Science.gov (United States)

    Serefko, Anna; Szopa, Aleksandra; Poleszak, Ewa

    2016-03-01

    Magnesium is one of the most important elements in the human body and is involved in a number of biochemical processes crucial for the proper functioning of the cardiovascular, alimentary, endocrine, and osteoarticular systems. It also plays a vital modulatory role in brain biochemistry, influencing several neurotransmission pathways associated with the development of depression. Personality changes, including apathy, depression, agitation, confusion, anxiety, and delirium are observed when there is a deficiency of this element. Rodents receiving a diet deficient in magnesium displayed depressive behaviour that was reversed by antidepressant drugs. Poor nutrition, gastrointestinal and renal diseases, insulin resistance and/or type 2 diabetes, alcoholism, stress, and certain medications may lead to magnesium deficiency. Since the extracellular concentration of magnesium ions may not reflect their intracellular level, none of the current methods of evaluating magnesium status is regarded as satisfactory. The mood-improving potential of magnesium compounds have been confirmed by the results of numerous pre-clinical and clinical studies. It seems that magnesium supplementation is well-tolerated and enhances the efficacy of conventional antidepressant treatments, and as such could be a valuable addition to the standard treatments for depression, although differences in bioavailability between inorganic and organic compounds should be taken into consideration.

  2. Physicochemical action of potassium-magnesium citrate in nephrolithiasis

    Science.gov (United States)

    Pak, C. Y.; Koenig, K.; Khan, R.; Haynes, S.; Padalino, P.

    1992-01-01

    Effect of potassium-magnesium citrate on urinary biochemistry and crystallization of stone-forming salts was compared with that of potassium citrate at same dose of potassium in five normal subjects and five patients with calcium nephrolithiasis. Compared to the placebo phase, urinary pH rose significantly from 6.06 +/- 0.27 to 6.48 +/- 0.36 (mean +/- SD, p less than 0.0167) during treatment with potassium citrate (50 mEq/day for 7 days) and to 6.68 +/- 0.31 during therapy with potassium-magnesium citrate (containing 49 mEq K, 24.5 mEq Mg, and 73.5 mEq citrate per day). Urinary pH was significantly higher during potassium-magnesium citrate than during potassium citrate therapy. Thus, the amount of undissociated uric acid declined from 118 +/- 61 mg/day during the placebo phase to 68 +/- 54 mg/day during potassium citrate treatment and, more prominently, to 41 +/- 46 mg/day during potassium-magnesium citrate therapy. Urinary magnesium rose significantly from 102 +/- 25 to 146 +/- 37 mg/day during potassium-magnesium citrate therapy but not during potassium citrate therapy. Urinary citrate rose more prominently during potassium-magnesium citrate therapy (to 1027 +/- 478 mg/day from 638 +/- 252 mg/day) than during potassium citrate treatment (to 932 +/- 297 mg/day). Consequently, urinary saturation (activity product) of calcium oxalate declined significantly (from 1.49 x 10(-8) to 1.03 x 10(-8) M2) during potassium-magnesium citrate therapy and marginally (to 1.14 x 10(-8) M2) during potassium citrate therapy.(ABSTRACT TRUNCATED AT 250 WORDS).

  3. Comparison of Dolomite Crystal Structure, Calcinations Dolomite and Magnesium Hydroxide in Partial Calcinations and Slaking Process

    Science.gov (United States)

    Sulistiyono, E.; Firdiyono, F.; Natasha, NC; Amalia, Y.

    2017-02-01

    Dolomite is a mineral that consists of calcium carbonate and magnesium carbonate with various mole ratio depend on the formation of mineral source. Recently, Utilization of dolomite only used as raw material for fertilizer and building materials, so that the enhancement of its added value becomes low. If the components in dolomite can be separated, magnesium carbonate and calcium carbonate will be produced then provide high added value. To separate these two components in dolomite is through partial calcinations followed by slaking process. The purpose of this paper is to prove that the partial calcinations can be used as a fundamental process for calcium and magnesium separation process in dolomite. SEM-EDX and XRD analysis proved that partial calcinations at 675°C for 6 hours is able to produce magnesium oxide (MgO) and calcium oxide (CaO). Then sea water was added to calcinations product so magnesium hydroxide and calcium carbonate that easily separated by sea water. The weakness of partial calcinations process at 675°C and processing time 2 hours is the dolomite has not perfectly reacted yet. XRD analysis showed that MgCO3. CaCO3 compounds still exist, so there is a possibility that magnesium was not fetched after the separation process.

  4. Magnesium sulphate for preventing preterm birth in threatened preterm labour.

    Science.gov (United States)

    Crowther, Caroline A; Brown, Julie; McKinlay, Christopher J D; Middleton, Philippa

    2014-08-15

    Magnesium sulphate has been used in some settings as a tocolytic agent to inhibit uterine activity in women in preterm labour with the aim of preventing preterm birth. To assess the effects of magnesium sulphate therapy given to women in threatened preterm labour with the aim of preventing preterm birth and its sequelae. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (last searched 31 January 2014). Randomised controlled trials of magnesium sulphate as the only tocolytic, administered by any route, compared with either placebo, no treatment or alternative tocolytic therapy (not magnesium sulphate) to women considered to be in preterm labour. At least two review authors assessed trial eligibility and risk of bias and undertook data extraction independently. The 37 included trials (total of 3571 women and over 3600 babies) were generally of moderate to high risk of bias. Antenatal magnesium sulphate was compared with either placebo, no treatment, or a range of alternative tocolytic agents.For the primary outcome of giving birth within 48 hours after trial entry, no significant differences were seen between women who received magnesium sulphate and women who did not (whether placebo/no alternative tocolytic drug, betamimetics, calcium channel blockers, cox inhibitors, prostaglandin inhibitors, or human chorionic gonadotropin) (19 trials, 1913 women). Similarly for the primary outcome of serious infant outcome, there were no significant differences between the infants exposed to magnesium sulphate and those not (whether placebo/no alternative tocolytic drug, betamimetics, calcium channel blockers, cox inhibitors, prostaglandin inhibitors, human chorionic gonadotropin or various tocolytic drugs) (18 trials; 2187 babies). No trials reported the outcome of extremely preterm birth. In the seven trials that reported serious maternal outcomes, no events were recorded.In the group treated with magnesium sulphate compared with women receiving

  5. Calcium Carbonate

    Science.gov (United States)

    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 ...

  6. Calcium supplements

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007477.htm Calcium supplements To use the sharing features on this page, please enable JavaScript. WHO SHOULD TAKE CALCIUM SUPPLEMENTS? Calcium is an important mineral for the ...

  7. Impurities Removal in Seawater to Optimize the Magnesium Extraction

    Science.gov (United States)

    Natasha, N. C.; Firdiyono, F.; Sulistiyono, E.

    2017-02-01

    Magnesium extraction from seawater is promising way because magnesium is the second abundant element in seawater and Indonesia has the second longest coastline in the world. To optimize the magnesium extraction, the impurities in seawater need to be eliminated. Evaporation and dissolving process were used in this research to remove the impurities especially calcium in seawater. Seawater which has been evaporated from 100 ml to 50 ml was dissolved with variations solution such as oxalic acid and ammonium bicarbonate. The solution concentration is 100 g/l and it variations are 2 ml, 4 ml, 6 ml, 8 ml, 10 ml, 20 ml, 30 ml, 40 ml and 50 ml. This step will produce precipitate and filtrate then it will be analysed to find out the result of this process. The precipitate was analysed by X-ray Diffraction (XRD) and Scanning Electron Microscope (SEM) but the filtrate was analysed by Inductively Coupled Plasma (ICP). XRD analysis shows that calcium oxalate and calcium carbonate were formed and ICP analysis shows that the remaining calcium in seawater using oxalic acid is about 0.01% and sodium 0.14% but when using ammonium bicarbonate the remaining calcium is 2.5% and sodium still more than 90%. The results show that both oxalic acid and ammonium bicarbonate can remove the impurities but when using oxalic acid, not only the impurities but also magnesium was precipitated. The conclusion of this research is the best solution to remove the impurities in seawater without precipitate the magnesium is using ammonium bicarbonate.

  8. Discussion about magnesium phosphating

    OpenAIRE

    Pokorny, P.; Tej, P.; Szelag, P.

    2016-01-01

    The paper describes results from recently published research focused on production of non-conventional magnesium phosphate Mg3(PO4)2・4H2O – bobierrite, or MgHPO4・3H2O – newberyite) coating for both magnesium alloys and/or mild steel. This new kind of coating is categorized in the context of current state of phosphating technology and its potential advantages and crystal structure is discussed. At the same time, the suitable comparison techniques for magnesium phosphate coating and convention...

  9. Discussion about magnesium phosphating

    Directory of Open Access Journals (Sweden)

    P. Pokorny

    2016-07-01

    Full Text Available The paper describes results from recently published research focused on production of non-conventional magnesium phosphate Mg3(PO42・4H2O – bobierrite, or MgHPO4・3H2O – newberyite coating for both magnesium alloys and/or mild steel. This new kind of coating is categorized in the context of current state of phosphating technology and its potential advantages and crystal structure is discussed. At the same time, the suitable comparison techniques for magnesium phosphate coating and conventional zinc phosphate coating are discussed.

  10. Magnesium reduces calcification in bovine vascular smooth muscle cells in a dose-dependent manner

    Science.gov (United States)

    Peter, Mirjam E.; Sevinc Ok, Ebru; Celenk, Fatma Gul; Yilmaz, Mumtaz; Steppan, Sonja; Asci, Gulay; Ok, Ercan; Passlick-Deetjen, Jutta

    2012-01-01

    Background. Vascular calcification (VC), mainly due to elevated phosphate levels, is one major problem in patients suffering from chronic kidney disease. In clinical studies, an inverse relationship between serum magnesium and VC has been reported. However, there is only few information about the influence of magnesium on calcification on a cellular level available. Therefore, we investigated the effect of magnesium on calcification induced by β-glycerophosphate (BGP) in bovine vascular smooth muscle cells (BVSMCs). Methods. BVSMCs were incubated with calcification media for 14 days while simultaneously increasing the magnesium concentration. Calcium deposition, transdifferentiation of cells and apoptosis were measured applying quantification of calcium, von Kossa and Alizarin red staining, real-time reverse transcription–polymerase chain reaction and annexin V staining, respectively. Results. Calcium deposition in the cells dramatically increased with addition of BGP and could be mostly prevented by co-incubation with magnesium. Higher magnesium levels led to inhibition of BGP-induced alkaline phosphatase activity as well as to a decreased expression of genes associated with the process of transdifferentiation of BVSMCs into osteoblast-like cells. Furthermore, estimated calcium entry into the cells decreased with increasing magnesium concentrations in the media. In addition, higher magnesium concentrations prevented cell damage (apoptosis) induced by BGP as well as progression of already established calcification. Conclusions. Higher magnesium levels prevented BVSMC calcification, inhibited expression of osteogenic proteins, apoptosis and further progression of already established calcification. Thus, magnesium is influencing molecular processes associated with VC and may have the potential to play a role for VC also in clinical situations. PMID:21750166

  11. Effects of a low-radiotoxicity uranium salt (uranyl acetate) on biochemical and hematological parameters of the catfish, Clarias gariepinus

    Science.gov (United States)

    Al-Ghanim, Khalid A.; Ahmad, Zubair; Al-Kahem Al-Balawi, Hmoud F.; Al-Misned, Fahad; Maboob, Shahid; Suliman, El-Amin M.

    2016-01-01

    Specimens of Clarias gariepinus were treated with lethal (70, 75, 80, 85, 90, and 95 mg/L) and sub-lethal concentrations (8, 12 and 16 mg/L) of uranyl acetate, a low-radiotoxicity uranium salt. The LC 50 value was registered as 81.45 mg/L. The protein and glycogen concentrations in liver and muscles were decreased in the fish exposed to sub-lethal concentrations. The red blood cell (RBC) and white blood cell (WBC) counts, haemoglobin (Hb) concentration and haematocrit (Hct) values were decreased. Different blood indices like mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were negatively affected. Level of plasma glucose was elevated whereas protein was decreased. The level of calcium concentration (Ca) was declined in the blood of exposed fish whereas magnesium (Mg) remains unchanged. The activity level of glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) was elevated in exposed fish. These effects were more pronounced in the last period of exposure and in higher concentrations. Results of the present study indicate that uranyl acetate has adverse effects on Clarias gariepinus and causes changes in the biochemical and hematological parameters of the fish.

  12. Hydrogen generation from magnesium hydride by using organic acid

    Science.gov (United States)

    Ho, Yen-Hsi

    In this paper, the hydrolysis of solid magnesium hydride has been studied with the high concentration of catalyst at the varying temperature. An organic acid (acetic acid, CH3COOH) has been chosen as the catalyst. The study has three objectives: first, using three different weights of MgH 2 react with aqueous solution of acid for the hydrogen generation experiments. Secondly, utilizing acetic acid as the catalyst accelerates hydrogen generation. Third, emphasizing the combination of the three operating conditions (the weight of MgH2, the concentration of acetic acid, and the varying temperature) influence the amount of hydrogen generation. The experiments results show acetic acid truly can increase the rate of hydrogen generation and the weight of MgH2 can affect the amount of hydrogen generation more than the varying temperature.

  13. Sol - Gel synthesis and characterization of magnesium peroxide nanoparticles

    Science.gov (United States)

    Jaison, J.; Ashok raja, C.; Balakumar, S.; Chan, Y. S.

    2015-04-01

    Magnesium peroxide is an excellent source of oxygen in agriculture applications, for instance it is used in waste management as a material for soil bioremediation to remove contaminants from polluted underground water, biological wastes treatment to break down hydrocarbon, etc. In the present study, sol-gel synthesis of magnesium peroxide (MgO2) nanoparticles is reported. Magnesium peroxide is odourless; fine peroxide which releases oxygen when reacts with water. During the sol-gel synthesis, the magnesium malonate intermediate is formed which was then calcinated to obtain MgO2 nanoparticles. The synthesized nanoparticles were characterized using Thermo gravimetric -Differential Thermal Analysis (TG- DTA), X-Ray Diffraction studies (XRD) and High Resolution Transmission Electron Microscope (HRTEM). Our study provides a clear insight that the formation of magnesium malonate during the synthesis was due to the reaction between magnesium acetate, oxalic acid and ethanol. In our study, we can conclude that the calcination temperature has a strong influence on particle size, morphology, monodispersity and the chemistry of the particles.

  14. Direct-reading spectrochemical analysis of magnesium alloys; Analisis espectroquimico de lectura directa de aleaciones de magnesio

    Energy Technology Data Exchange (ETDEWEB)

    Roca Adell, M.

    1964-07-01

    A Quantometer has been applied to the determination of aluminum, berylium, calcium, iron, silicon and zinc in magnesium alloys Magnox, after the conversion of the samples to the oxide. For the aluminum, whose concentration is relatively high, the conducting briquets technique with an interrupted discharge is employed, using the magnesium as the internal standard. For the other elements a total burning method with direct current arc is employed, using also the magnesium as the internal standard. (Author) 7 refs.

  15. [Magnesium and bronchopulmonary dysplasia].

    Science.gov (United States)

    Fridman, Elena; Linder, Nehama

    2013-03-01

    Bronchopulmonary dysplasia (BPD) is a chronic lung disease that occurs in premature infants who have needed mechanical ventilation and oxygen therapy. BPD is defined as the presence of persistent respiratory symptoms, the need for supplemental oxygen to treat hypoxemia, and an abnormal chest radiograph at 36 weeks gestational age. Proinflammatory cytokines and altered angiogenic gene signaling impair prenatal and postnatal lung growth, resulting in BPD. Postnatal hyperoxia exposure further increases the production of cytotoxic free radicals, which cause lung injury and increase the levels of proinflammatory cytokines. Magnesium is the fourth most abundant metal in the body. It is commonly used for the treatment of preeclamsia, as well as for premature labor alleviation. Magnesium's role in BPD development is not clear. A significant association between high magnesium levels at birth and respiratory distress syndrome (RDS), pulmonary interstitial emphysema in the extremely low birth weight, respiratory failure, and later development BPD was found. Conversely, low magnesium intake is associated with lower lung functions, and hypomagnesemia was found in 16% of patients with acute pulmonary diseases. Magnesium is used for the treatment of asthmatic attacks. Magnesium deficiency in pregnant women is frequently seen due to low intake. Hypomagnesemia was also found among preterm neonates and respiratory distress syndrome (RDS). Experimental hypomagnesemia evokes an inflammatory response, and oxidative damage of tissues. These were accompanied by changes in gene expression mostly involved in regulation of cell cycle, apoptosis and remodeling, processes associated with BPD. It is rational to believe that hypomagnesemia can contribute to BPD pathogenesis.

  16. Electrodeposition of magnesium and magnesium/aluminum alloys

    Science.gov (United States)

    Mayer, A.

    1988-01-21

    Electrolytes and plating solutions for use in processes for electroplating and electroforming pure magnesium and alloys of aluminum and magnesium and also electrodeposition processes. An electrolyte of this invention is comprised of an alkali metal fluoride or a quaternary ammonium halide, dimethyl magnesium and/or diethyl magnesium, and triethyl aluminum and/or triisobutyl aluminum. An electrolyte may be dissolved in an aromatic hydrocarbon solvent to form a plating solution. The proportions of the component compounds in the electrolyte are varied to produce essentially pure magnesium or magnesium/aluminum alloys having varying selected compositions.

  17. [Arrhythmogenic effect of flecainide--treatment with i.v. magnesium].

    Science.gov (United States)

    Mletzko, R; Jung, W; Manz, M; Kamradt, T; Vogel, F; Lüderitz, B

    1989-09-01

    We report on a 46-year-old woman with ventricular tachycardia and ventricular fibrillation after starting antiarrhythmic drug therapy with flecainide. The flecainide acetate plasma levels were always in the normal range. A successful therapeutical intervention was induced with two i.v. applications of 1,000 mg magnesium glutamate. A persistent suppression of ventricular rhythm disturbance was accomplished by continuous i.v. application of 4 mg magnesium glutamate/min.

  18. The Role of Magnesium in Post-thyroidectomy Hypocalcemia.

    Science.gov (United States)

    Cherian, Anish Jacob; Gowri, Mahasampath; Ramakant, Pooja; Paul, Thomas V; Abraham, Deepak Thomas; Paul, Mazhuvanchary Jacob

    2016-04-01

    The purpose of this study was to determine the prevalence of hypomagnesemia in patients undergoing thyroidectomy and evaluate the relationship of hypomagnesemia with transient and severe hypocalcemia. This was a prospective observational study of 50 patients undergoing thyroidectomy. Blood samples were collected pre- and postoperatively for calcium, albumin, magnesium, phosphorous and parathormone (PTH). Signs, symptoms of hypocalcemia and volume of intravenous fluids used perioperatively were documented. The statistical analysis was performed using STATA I/C 10.1. Preoperatively, twelve patients (24 %) had hypomagnesemia and one (2 %) hypocalcemia. On the first postoperative day, hypomagnesemia was seen in 70 % and hypocalcemia in 30 %. A similar trend was observed in the fall and rise of postoperative calcium and magnesium values (p = 0.41). Severe hypocalcemia was present in three patients (6 %). All three patients had a very low postoperative PTH (postoperative hypocalcemia include a higher volume of fluid used perioperatively and low postoperative PTH (Postoperative hypomagnesemia is a common event (70 %) following total thyroidectomy, and magnesium levels tend to mimic the calcium levels postoperatively. The cause of hypocalcemia post-thyroidectomy in this study is mainly a factor of parathyroid function and fluid status. Severe hypocalcemia is a rare event, and hypomagnesemia is associated in the majority of these patients. The role of magnesium correction to alleviate severe hypocalcemia needs to be further studied.

  19. Effect of calcium and magnesium silicate on the growth of the castor oil plant subjected to salinity levels Efeito de silicato de cálcio e magnésio sobre o crescimento de plantas de mamoneira submetidas a níveis de salinidade

    Directory of Open Access Journals (Sweden)

    José Félix Brito Neto

    2012-12-01

    Full Text Available Salt stress decreases the osmotic potential of soil solution causing water stress, causing toxic effects in the plants resulting in injuries on the metabolism and nutritional disorders, thus compromising the plant growth, resulting in lower production. The calcium silicate and magnesium can perform the same function as limestone, besides providing silicon to plants, may also contribute to the resistance of plants to salt stress. Thus, the objective of this study was to evaluate the effect of calcium and magnesium silicate on the growth of the castor oil plant BRS Energia cultivated under saline conditions. This study evaluated plant height, stem diameter, number of leaves, leaf area, dry weight of shoot and root, and soil chemical characteristics. There was no interaction between factors of salinity level and of silicate level regarding the evaluated variables. There was a direct relationship between salinity levels and plant growth in height and stem diameter. The K concentration in soil were affected by salinity levels. O estresse salino diminui o potencial osmótico da solução do solo causando estresse hídrico, provocando efeitos tóxicos nas plantas que resultam em injúrias no metabolismo e desordens nutricionais, comprometendo assim o crescimento das plantas, resultando em menor produção. O silicato de cálcio e magnésio pode desempenhar a mesma função do calcário, além de fornecer silício para as plantas, podendo ainda, contribuir para a resistência de plantas ao estresse salino. Nesse sentido, objetivou-se com esse trabalho avaliar o efeito do silicato de cálcio e magnésio no crescimento da mamoneira BRS Energia cultivada sob condições salinas. Avaliou-se a altura da planta, diâmetro do caule, número de folhas, área foliar, massa seca da parte aérea e da raiz e as características químicas do solo. Não houve interação entre os fatores níveis de salinidade e silicato sobre as variáveis analisadas. Houve rela

  20. Intercomparison 9711. pH, conductivity, alkalinity, nitrate + nitrite, chloride, sulfate, calcium, magnesium, sodium, potassium, total aluminium, reactive and non-labile aluminium, dissolved organic carbon, and chemical oxygen demand (ICP Waters report)

    OpenAIRE

    Hovind, H.

    1997-01-01

    47 laboratories in 22 countries participated in intercomparison 9711. One sample set for the determination of major ions, organic matter and aluminium fractions, were used. Based on the general target accuracy of + 20%, 78% of the results were acceptable. More than 80% of the result pairs were acceptable for chloride, sulfate, calcium, mangnesium, sodium, dissolved organic carbon and chemical oxygen demand. For pH only 43% of the result pairs were acceptable in relation to the extended target...

  1. Estimation of presynaptic calcium currents and endogenous calcium buffers at the frog neuromuscular junction with two different calcium fluorescent dyes

    Directory of Open Access Journals (Sweden)

    Dmitry eSamigullin

    2015-01-01

    Full Text Available At the frog neuromuscular junction, under physiological conditions, the direct measurement of calcium currents and of the concentration of intracellular calcium buffers—which determine the kinetics of calcium concentration and neurotransmitter release from the nerve terminal—has hitherto been technically impossible. With the aim of quantifying both Ca2+ currents and the intracellular calcium buffers, we measured fluorescence signals from nerve terminals loaded with the low-affinity calcium dye Magnesium Green or the high-affinity dye Oregon Green BAPTA-1, simultaneously with microelectrode recordings of nerve-action potentials and end-plate currents. The action-potential-induced fluorescence signals in the nerve terminals developed much more slowly than the postsynaptic response. To clarify the reasons for this observation and to define a spatiotemporal profile of intracellular calcium and of the concentration of mobile and fixed calcium buffers, mathematical modeling was employed. The best approximations of the experimental calcium transients for both calcium dyes were obtained when the calcium current had an amplitude of 1.6 ± 0.08 рА and a half-decay time of 1.2 ± 0.06 ms, and when the concentrations of mobile and fixed calcium buffers were 250 ± 13 µM and 8 ± 0.4 mM, respectively. High concentrations of endogenous buffers define the time course of calcium transients after an action potential in the axoplasm, and may modify synaptic plasticity.

  2. Magnesium-containing mixed coatings on zirconia for dental implants: mechanical characterization and in vitro behavior.

    Science.gov (United States)

    Pardun, Karoline; Treccani, Laura; Volkmann, Eike; Streckbein, Philipp; Heiss, Christian; Gerlach, Juergen W; Maendl, Stephan; Rezwan, Kurosch

    2015-07-01

    An important challenge in the field of dental and orthopedic implantology is the preparation of implant coatings with bioactive functions that feature a high mechanical stability and at the same time mimic structural and compositional properties of native bone for a better bone ingrowth. This study investigates the influence of magnesium addition to zirconia-calcium phosphate coatings. The mixed coatings were prepared with varying additions of either magnesium oxide or magnesium fluoride to yttria-stabilized zirconia and hydroxyapatite. The coatings were deposited on zirconia discs and screw implants by wet powder spraying. Microstructure studies confirm a porous coating with similar roughness and firm adhesion not hampered by the coating composition. The coating morphology, mechanical flexural strength and calcium dissolution showed a magnesium content-dependent effect. Moreover, the in vitro results obtained with human osteoblasts reveal an improved biological performance caused by the presence of Mg(2+) ions. The magnesium-containing coatings exhibited better cell proliferation and differentiation in comparison to pure zirconia-calcium phosphate coatings. In conclusion, these results demonstrate that magnesium addition increases the bioactivity potential of zirconia-calcium phosphate coatings and is thus a highly suitable candidate for bone implant coatings. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  3. [Plasma ionized magnesium concentration following cardiopulmonary bypass].

    Science.gov (United States)

    Amaya, Fumimasa; Fukui, Michihiko; Tsuruta, Hiroshi; Kooguchi, Kunihiko; Shimosato, Goshun

    2002-06-01

    We performed a retrospective study to analyze plasma ionized magnesium concentration following cardiopulmonary bypass. Severe decrease of ionized magnesium concentration associated with frequent abnormal ECG sign was found in a patient with magnesium-free cardioplegia. Cardioplegia containing 16 mmol.l-1 of magnesium ion maintained ionized magnesium concentration within normal ranges without postoperative magnesium loading. Use of cardioplegia containing magnesium or adequate magnesium supplement is thought to be essential for patients receiving cardiopulmonary bypass.

  4. Kinetics of Leaching Calcium from Dolomite

    Directory of Open Access Journals (Sweden)

    Azizi, A.

    2011-06-01

    Full Text Available Magnesia is obtained from magnesite ore and the production process applied should remove accompanying minerals that reduce its refractoriness. Given that magnesite reservoirs are more exploited and largely exhausted, there is a growing need for production of magnesia on the basis of other magnesium minerals. Dolomite is a promising source of magnesia because it forms large deposits, is easy to exploit, and generally contains a small quantity of impurities.The kinetics of calcium leaching from dolomite by magnesium-nitrate solution has been studied. The research program included the influence of temperature, mass fraction of magnesium nitrate in solution, dolomite particle size and leaching time. Time dependence of calcium leaching is described by relevant kinetic equations. Rate coefficients, their temperature dependence and Arrhenius activation energy have been determined.

  5. Bronchial reactivity and intracellular magnesium: a possible mechanism for the bronchodilating effects of magnesium in asthma.

    Science.gov (United States)

    Dominguez, L J; Barbagallo, M; Di Lorenzo, G; Drago, A; Scola, S; Morici, G; Caruso, C

    1998-08-01

    1. Increased bronchial smooth muscle contractility with consequent bronchial hyperreactivity are characteristic physiopathological events of asthma. Since magnesium intervenes in calcium transport mechanisms and intracellular phosphorylation reactions, it constitutes an important determinant of the contraction/relaxation state of bronchial smooth muscle. In the present study we investigated the relationship between bronchial reactivity, assessed by methacholine-provocation test, and magnesium concentrations both at extracellular and intracellular levels measured by spectrophotometry. Twenty-two patients with mild-to-moderate asthma and 38 non-asthmatic subjects with allergic rhinitis (24 allergic to Parietaria pollen and 14 allergic to Grass pollen) were recruited to the study. Exclusion criteria included renal failure, hepatic diseases, heart failure and arterial hypertension. 2. The salient finding of our study is that there is a strong positive correlation between bronchial reactivity and the level of intracellular magnesium (r=0.72, Pmagnesium concentrations in the group of patients with asthma were significantly lower (1.8+/-0. 01 mmol/l; n=22) when compared with levels in rhinitis subjects allergic to Parietaria (1.9+/-0.01 mmol/l; n=24, Pmagnesium may be an important determinant of bronchial hyperreactivity, as supported by the significant positive correlation between these two parameters in allergic patients with known bronchial hyperresponsiveness. This finding, in addition to reports of the bronchodilating effects of magnesium administration in patients with asthma, confirms the proposed role of this ion in the pathogenesis and treatment of asthma.

  6. Synthesis and anion-exchange reactions of a new anionic clay, α-magnesium hydroxide.

    Science.gov (United States)

    Nethravathi, C; Rajamathi, Jacqueline T; George, Preeta; Rajamathi, Michael

    2011-02-15

    A new anionic clay, α-magnesium hydroxide, was synthesized by hydrolysis of magnesium acetate in propylene glycol. The structure of this α-hydroxide is similar to that of hydrotalcites. It consists of positively charged magnesium hydroxide layers arising out of partial protonation of the hydroxyl groups of the [Mg(OH)(2)] layers and loosely held anions in the interlayer region. As expected it ages readily in water to give β-magnesium hydroxide, brucite. While anion-exchange reactions of α-magnesium hydroxide could not be carried out in aqueous medium a number of anion-exchange reactions could be carried out successfully in ethanol medium. Copyright © 2010 Elsevier Inc. All rights reserved.

  7. Magnesium Borohydride: From Hydrogen Storage to Magnesium Battery**

    OpenAIRE

    Mohtadi, Rana; Matsui, Masaki; Arthur, Timothy S.; Hwang, Son-Jong

    2012-01-01

    Beyond hydrogen storage: The first example of reversible magnesium deposition/stripping onto/from an inorganic salt was seen for a magnesium borohydride electrolyte. High coulombic efficiency of up to 94 % was achieved in dimethoxyethane solvent. This Mg(BH_4)_2 electrolyte was utilized in a rechargeable magnesium battery.

  8. 21 CFR 184.1434 - Magnesium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium phosphate. 184.1434 Section 184.1434 Food... Specific Substances Affirmed as GRAS § 184.1434 Magnesium phosphate. (a) Magnesium phosphate includes both magnesium phosphate, dibasic, and magnesium phosphate, tribasic. Magnesium phosphate, dibasic (MgHPO4·3H2O...

  9. [Determination of soil exchangeable base cations by using atomic absorption spectrophotometer and extraction with ammonium acetate].

    Science.gov (United States)

    Zhang, Yu-ge; Xiao, Min; Dong, Yi-hua; Jiang, Yong

    2012-08-01

    A method to determine soil exchangeable calcium (Ca), magnesium (Mg), potassium (K), and sodium (Na) by using atomic absorption spectrophotometer (AAS) and extraction with ammonium acetate was developed. Results showed that the accuracy of exchangeable base cation data with AAS method fits well with the national standard referential soil data. The relative errors for parallel samples of exchangeable Ca and Mg with 66 pair samples ranged from 0.02%-3.14% and 0.06%-4.06%, and averaged to be 1.22% and 1.25%, respectively. The relative errors for exchangeable K and Na with AAS and flame photometer (FP) ranged from 0.06%-8.39% and 0.06-1.54, and averaged to be 3.72% and 0.56%, respectively. A case study showed that the determination method for exchangeable base cations by using AAS was proven to be reliable and trustable, which could reflect the real situation of soil cation exchange properties in farmlands.

  10. Aluminum Hydroxide and Magnesium Hydroxide

    Science.gov (United States)

    Aluminum Hydroxide, Magnesium Hydroxide are antacids used together to relieve heartburn, acid indigestion, and upset stomach. They ... They combine with stomach acid and neutralize it. Aluminum Hydroxide, Magnesium Hydroxide are available without a prescription. ...

  11. INVESTIGATION OF MAGNESIUM ALLOYS MACHINABILITY

    Directory of Open Access Journals (Sweden)

    Berat Barıs BULDUM

    2013-01-01

    Full Text Available Magnesium is the lightest structural metal. Magnesium alloys have a hexagonal lattice structure, which affects the fundamental properties of these alloys. Plastic deformation of the hexagonal lattice is more complicated than in cubic latticed metals like aluminum, copper and steel. Magnesium alloy developments have traditionally been driven by industry requirements for lightweight materials to operate under increasingly demanding conditions. Magnesium alloys have always been attractive to designers due to their low density, only two thirds that of aluminium and its alloys [1]. The element and its alloys take a big part of modern industry needs. Especially nowadays magnesium alloys are used in automotive and mechanical (trains and wagons manufacture, because of its lightness and other features. Magnesium and magnesium alloys are the easiest of all metals to machine, allowing machining operations at extremely high speed. All standard machining operations such as turning, drilling, milling, are commonly performed on magnesium parts.

  12. Intercomparison 9610, pH, conductivity, alkalinity, nitrate + nitrite, chloride, sulfate, calcium, magnesium, sodium, potassium, total aluminium, reactive and non-labile aluminium, dissolved organic carbon, and chemical oxygen demand (ICP Waters report)

    OpenAIRE

    Hovind, H.

    1996-01-01

    36 laboratories in 21 countries participated in intercomparison 9610. Two sample sets, one for the major ions and one for organic matter and aluminium fractions, were used. Based on the general target accuracy of + 20%, 70% of the results were acceptable. More than 80% of the result pairs were acceptable for conductivity, nitrate+nitrite, calcium, sodium and dissolved organic carbon. For pH only 55% of the result pairs were acceptable in relation to the extended target accuracy of + 0.2 units...

  13. Extracellular magnesium decreases the secretory response of rat peritoneal mast cells to compound 48/80 in vitro

    DEFF Research Database (Denmark)

    Bertelsen, Niels Haldor; Johansen, Torben

    1991-01-01

    Exposure of rat peritoneal mast cells to magnesium in the absence of extracellular calcium resulted in a time- and dose-dependent decrease in the secretory response induced by compound 48/80. The decrease was prevented by a low extracellular concentration of calcium. Furthermore, the decreased...... and the secretory stimulus. A dose-dependent decrease in antigen induced histamine secretion that was reversed by calcium was also observed. Exposure of the mast cells to magnesium for 15 min resulted in a parallel decrease in histamine secretion and in the cellular content of 45Ca2+. These observations suggest...... secretory responsiveness was dose-dependently restored by the addition of calcium to the cells simultaneously with compound 48/80. Preincubation with magnesium also inhibited antigen-induced histamine secretion in a dose-dependent manner. This was reversed by the simultaneous addition of calcium...

  14. INVESTIGATION OF MAGNESIUM ALLOYS MACHINABILITY

    OpenAIRE

    Berat Barıs BULDUM; Aydın SIK; Iskender OZKUL

    2013-01-01

    Magnesium is the lightest structural metal. Magnesium alloys have a hexagonal lattice structure, which affects the fundamental properties of these alloys. Plastic deformation of the hexagonal lattice is more complicated than in cubic latticed metals like aluminum, copper and steel. Magnesium alloy developments have traditionally been driven by industry requirements for lightweight materials to operate under increasingly demanding conditions. Magnesium alloys have always been attra...

  15. Mechanical characteristics of biodegradable magnesium matrix composites: A review

    Directory of Open Access Journals (Sweden)

    Meysam Haghshenas

    2017-06-01

    Full Text Available In recent years, a new generation of biodegradable metallic materials, magnesium alloys, has been called a revolutionary material for biomedical applications (i.e. in orthopedics applications as a bone-implant material, thanks to the reasonable strength (similar to bone tissue, compared to available metallic alloys and high biocompatibility of magnesium and its alloys. However, pure magnesium can corrode too quickly in the physiological pH (7.4–7.6 and high chloride environment of the physiological system and therefore lose their mechanical integrity before tissues have sufficiently. Engineering approach to this challenge (high corrosion rate of Mg can be (i alloying of element additions, (ii surface treatment and (iii development of metal (magnesium matrix composites (MMCs. Magnesium-based composites, as bio-materials, can provide a combination of unique characteristics including adjustable mechanical properties (i.e. tensile strength, elastic modulus, ductility and corrosion resistance. This is the main advantage of magnesium-based composites as compared with alloying and surface treatment approaches. Here, the matrix materials are biomedical magnesium alloys based on Mg–Zn, Mg–Ca and Mg–REE alloy systems (REE stands for rare earth elements including yttrium, Y, cerium, Ce, lanthanum, La. The reinforcement phases are mainly based on hydroxyapatite (HAP, calcium polyphosphate (CPP, and β-tricalcium phosphate (β-TCP particles, and hybrid HAP + β-TCP particles. In this paper a comprehensive review is provided on different grades of biodegradable magnesium matrix composites, with focus on their mechanical properties.

  16. Chemical speciation of uranium(VI) in marine environments: complexation of calcium and magnesium ions with [(UO{sub 2})(CO{sub 3}){sub 3}]{sup 4-} and the effect on the extraction of uranium from seawater

    Energy Technology Data Exchange (ETDEWEB)

    Endrizzi, Francesco; Rao, Linfeng [Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

    2014-10-27

    The interactions of Ca{sup 2+} and Mg{sup 2+} with [UO{sub 2}(CO{sub 3}){sub 3}]{sup 4-} were studied by calcium ion selective electrode potentiometry and spectrophotometry. The stability constants of ternary Ca-UO{sub 2}-CO{sub 3} and Mg-UO{sub 2}-CO{sub 3} complexes were determined with calcium ion selective electrode potentiometry and optical absorption spectrophotometry, respectively. The enthalpies of complexation for two successive complexes, [CaUO{sub 2}(CO{sub 3}){sub 3}]{sup 2-} and [Ca{sub 2}UO{sub 2}(CO{sub 3}){sub 3}](aq), were determined for the first time by microcalorimetry. The data help to revise the speciation of uranium(VI) species under seawater conditions. In contrast to the previously accepted assumption that the highly negatively charged [UO{sub 2}(CO{sub 3}){sub 3}]{sup 4-} is the dominant species, the revised speciation indicates that the dominant aqueous uranium(VI) species under seawater conditions is the neutral [Ca{sub 2}UO{sub 2}(CO{sub 3}){sub 3}](aq). The results have a significant impact on the strategies for developing efficient sorption processes to extract uranium from seawater. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. A Quick Reference on Magnesium.

    Science.gov (United States)

    Bateman, Shane W

    2017-03-01

    This article serves as a quick reference on the distribution, handling, and supplementation of magnesium. It also lists the manifestations and causes of magnesium deficit and provides criteria for the diagnosis of a magnesium deficit. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Magnesium - distribution and basic metabolism

    African Journals Online (AJOL)

    where it is regulated by parathyroid hormone'and. 1,25(OHb-D3. Most of the remaining magnesium pool is intracellular, plasma magnesium accounting ... various cell membrane functions.2 The recommended dietary allowance of magnesium varies from 5 mg/kg/d in healthy adult males to 6 mg/kg/d in children or during ...

  19. Laboratory study on the high-temperature capture of HCl gas by dry-injection of calcium-based sorbents.

    Science.gov (United States)

    Shemwell, B; Levendis, Y A; Simons, G A

    2001-01-01

    This is a laboratory study on the reduction of combustion-generated hydrochloric acid (HCl) emissions by in-furnace dry-injection of calcium-based sorbents. HCl is a hazardous gaseous pollutant emitted in significant quantities by municipal and hazardous waste incinerators, coal-fired power plants, and other industrial furnaces. Experiments were conducted in a laboratory furnace at gas temperatures of 600-1000 degrees C. HCl gas diluted with N2, and sorbent powders fluidized in a stream of air were introduced into the furnace concurrently. Chlorination of the sorbents occurred in the hot zone of the furnace at gas residence times approximately 1 s. The sorbents chosen for these experiments were calcium formate (CF), calcium magnesium acetate (CMA), calcium propionate (CP), calcium oxide (CX), and calcium carbonate (CC). Upon release of organic volatiles, sorbents calcine to CaO at approximately 700 degrees C, and react with the HCl according to the reaction CaO + 2HCl CaCl2 + H2O. At the lowest temperature case examined herein, 600 degrees C, direct reaction of HCl with CaCO3 may also be expected. The effectiveness of the sorbents to capture HCl was interpreted using the "pore tree" mathematical model for heterogeneous diffusion reactions. Results show that the thin-walled, highly porous cenospheres formed from the pyrolysis and calcination of CF, CMA, and CP exhibited high relative calcium utilization at the upper temperatures of this study. Relative utilizations under these conditions reached 80%. The less costly low-porosity sorbents, calcium carbonate and calcium oxide also performed well. Calcium carbonate reached a relative utilization of 54% in the mid-temperature range, while the calcium oxide reached an 80% relative utilization at the lowest temperature examined. The data matched theoretical predictions of sorbent utilization using the mathematical model, with activation energy and pre-exponential factors for the calcination reaction of 17,000 K and 300

  20. Calcium Modulation of Plant Plasma Membrane-Bound Atpase Activities

    Science.gov (United States)

    Caldwell, C.

    1983-01-01

    The kinetic properties of barley enzyme are discussed and compared with those of other plants. Possibilities for calcium transport in the plasma membrane by proton pump and ATPase-dependent calcium pumps are explored. Topics covered include the ph phase of the enzyme; high affinity of barley for calcium; temperature dependence, activation enthalpy, and the types of ATPase catalytic sites. Attention is given to lipids which are both screened and bound by calcium. Studies show that barley has a calmodulin activated ATPase that is found in the presence of magnesium and calcium.

  1. Standard test method for laboratory evaluation of magnesium sacrificial anode test specimens for underground applications

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1997-01-01

    1.1 This test method covers a laboratory procedure that measures the two fundamental performance properties of magnesium sacrificial anode test specimens operating in a saturated calcium sulfate, saturated magnesium hydroxide environment. The two fundamental properties are electrode (oxidation potential) and ampere hours (Ah) obtained per unit mass of specimen consumed. Magnesium anodes installed underground are usually surrounded by a backfill material that typically consists of 75 % gypsum (CaSO4·2H2O), 20 % bentonite clay, and 5 % sodium sulfate (Na2SO4). The calcium sulfate, magnesium hydroxide test electrolyte simulates the long term environment around an anode installed in the gypsum-bentonite-sodium sulfate backfill. 1.2 This test method is intended to be used for quality assurance by anode manufacturers or anode users. However, long term field performance properties may not be identical to property measurements obtained using this laboratory test. Note 1—Refer to Terminology G 15 for terms used ...

  2. Ulipristal acetate versus leuprolide acetate for uterine fibroids.

    Science.gov (United States)

    Donnez, Jacques; Tomaszewski, Janusz; Vázquez, Francisco; Bouchard, Philippe; Lemieszczuk, Boguslav; Baró, Francesco; Nouri, Kazem; Selvaggi, Luigi; Sodowski, Krzysztof; Bestel, Elke; Terrill, Paul; Osterloh, Ian; Loumaye, Ernest

    2012-02-02

    The efficacy and side-effect profile of ulipristal acetate as compared with those of leuprolide acetate for the treatment of symptomatic uterine fibroids before surgery are unclear. In this double-blind noninferiority trial, we randomly assigned 307 patients with symptomatic fibroids and excessive uterine bleeding to receive 3 months of daily therapy with oral ulipristal acetate (at a dose of either 5 mg or 10 mg) or once-monthly intramuscular injections of leuprolide acetate (at a dose of 3.75 mg). The primary outcome was the proportion of patients with controlled bleeding at week 13, with a prespecified noninferiority margin of -20%. Uterine bleeding was controlled in 90% of patients receiving 5 mg of ulipristal acetate, in 98% of those receiving 10 mg of ulipristal acetate, and in 89% of those receiving leuprolide acetate, for differences (as compared with leuprolide acetate) of 1.2 percentage points (95% confidence interval [CI], -9.3 to 11.8) for 5 mg of ulipristal acetate and 8.8 percentage points (95% CI, 0.4 to 18.3) for 10 mg of ulipristal acetate. Median times to amenorrhea were 7 days for patients receiving 5 mg of ulipristal acetate, 5 days for those receiving 10 mg of ulipristal acetate, and 21 days for those receiving leuprolide acetate. Moderate-to-severe hot flashes were reported for 11% of patients receiving 5 mg of ulipristal acetate, for 10% of those receiving 10 mg of ulipristal acetate, and for 40% of those receiving leuprolide acetate (Pulipristal acetate vs. leuprolide acetate). Both the 5-mg and 10-mg daily doses of ulipristal acetate were noninferior to once-monthly leuprolide acetate in controlling uterine bleeding and were significantly less likely to cause hot flashes. (Funded by PregLem; ClinicalTrials.gov number, NCT00740831.).

  3. Simultaneous incorporation of magnesium and carbonate in apatite: effect on physico-chemical properties

    OpenAIRE

    Sader,Marcia S.; Kanthi Lewis; Soares, Gloria A.; Racquel Z. LeGeros

    2013-01-01

    Synthetic apatites are widely used both in the dental and the orthopaedic fields due to their similarity in composition with the inorganic phase of hard tissues. Biologic apatites are not pure hydroxyapatite (HA), but are calcium-deficient apatites with magnesium and carbonate as minor but important substituents. The aim of the present study was to produce a more soluble biomaterial through the simultaneous substitution of magnesium and carbonate in the apatite structure to accelerate the deg...

  4. Magnesium oxychloride cement concrete

    Indian Academy of Sciences (India)

    TECS

    ting. It is used in industrial floorings, ship decks, railway passenger coach floorings, hospital floors, ammunition factory floors, missile silos and underground armament factories and bunkers. Recently, concrete of high compres- sive and tensile strength prepared with magnesium oxy- chloride cement and recycled rubber ...

  5. Effect of Magnesium Supplementation on the Distribution Patterns of Zinc, Copper, and Magnesium in Rabbits Exposed to Prolonged Cadmium Intoxication

    Directory of Open Access Journals (Sweden)

    Zorica Bulat

    2012-01-01

    Full Text Available The present study is designed to investigate whether magnesium (Mg supplementation may prevent Cd-induced alterations in zinc (Zn, copper (Cu, and magnesium (Mg status in rabbits. For this purpose, the concentrations of Zn, Cu, and Mg were estimated in blood, urine, and organs (brain, heart, lungs, liver, kidney, spleen, pancreas, skeletal muscle, and bone of rabbits given Cd (10 mg/kg b.w. and rabbits cotreated with Mg (40 mg/kg b.w. orally, as aqueous solutions of Cd chloride and Mg acetate every day for 4 weeks. Samples were mineralized with conc. HNO3 and HClO4 (4:1 and metals concentrations were determined by atomic absorption spectrophotometry (AAS. Magnesium supplementation succeeded to overcome Cd-induced disbalance of investigated bioelements. Beneficial effects of Mg were observed on Zn levels in blood and urine, on Cu levels in urine, and on Mg levels in blood. Magnesium pretreatment also managed to counteract or reduce all Cd-induced changes in levels of Cu and Mg in organs, while it did not exert this effect on Zn levels. These findings suggest that enhanced dietary Mg intake during Cd exposure can have at least partly beneficial effect on Cd-induced alterations in homeostasis of zinc, copper, and magnesium.

  6. Effect of magnesium supplementation on the distribution patterns of zinc, copper, and magnesium in rabbits exposed to prolonged cadmium intoxication.

    Science.gov (United States)

    Bulat, Zorica; Dukić-Ćosić, Danijela; Antonijević, Biljana; Bulat, Petar; Vujanović, Dragana; Buha, Aleksandra; Matović, Vesna

    2012-01-01

    The present study is designed to investigate whether magnesium (Mg) supplementation may prevent Cd-induced alterations in zinc (Zn), copper (Cu), and magnesium (Mg) status in rabbits. For this purpose, the concentrations of Zn, Cu, and Mg were estimated in blood, urine, and organs (brain, heart, lungs, liver, kidney, spleen, pancreas, skeletal muscle, and bone) of rabbits given Cd (10 mg/kg b.w.) and rabbits cotreated with Mg (40 mg/kg b.w.) orally, as aqueous solutions of Cd chloride and Mg acetate every day for 4 weeks. Samples were mineralized with conc. HNO₃ and HClO₄ (4:1) and metals concentrations were determined by atomic absorption spectrophotometry (AAS). Magnesium supplementation succeeded to overcome Cd-induced disbalance of investigated bioelements. Beneficial effects of Mg were observed on Zn levels in blood and urine, on Cu levels in urine, and on Mg levels in blood. Magnesium pretreatment also managed to counteract or reduce all Cd-induced changes in levels of Cu and Mg in organs, while it did not exert this effect on Zn levels. These findings suggest that enhanced dietary Mg intake during Cd exposure can have at least partly beneficial effect on Cd-induced alterations in homeostasis of zinc, copper, and magnesium.

  7. FOCUS ON MAGNESIUM BASED DRUGS

    Directory of Open Access Journals (Sweden)

    I. I. Esenova

    2011-01-01

    Full Text Available Magnesium deficiency in the organism is one of the most common human deficiency states. The prevalence of magnesium deficiency is about 15%, and suboptimal magnesium level is observed more than in 30% of people in the general population. Clinical signs of hypomagnesaemia are observed in 40% of patients in general care hospitals, in 70% of patients - in intensive care units, and magnesium deficiency occurs in 90% of patients with acute coronary syndrome. Magnesium metabolic disorders in the organism accelerate significantly development of complications of coronary heart disease, hypertension, type 2 diabetes, asthma and a number of neurological and psychiatric diseases. The value of this macro in the body is well studied, and its daily need is identified depending on age and sex. It is known that magnesium intake with the food does not cover an organism need. It is a rationale for preventive and therapeutic use of magnesium based drugs in various diseases. Organic salts of magnesium are recommended for these purposes. Magnesium metabolic disorders, approaches to pharmacotherapeutic correction of magnesium deficiency, advantages of magnesium salts of orotic acid are reviewed.

  8. Magnesium homeostasis and alcohol consumption.

    Science.gov (United States)

    Romani, Andrea M P

    2008-12-01

    Clinical and experimental evidence indicates alcohol consumption as one of the major causes of magnesium loss from several tissues. As a result of this loss, serum magnesium tends to decrease while urinary magnesium excretion increases 2-3 fold. Experimental data confirm that chronic consumption of 6% ethanol in the Lieber De-Carli diet for 3 weeks results in a marked decrease in total tissue magnesium content in rats. This decrease affects brain, liver and all skeletal muscle, including heart, to a varying extent. While a full picture of the implications of magnesium loss in these tissues is still lacking, it is becoming progressively clear that magnesium loss affects energy production, protein synthesis, cell cycle, and specific functions in the various organs affected. In addition, as magnesium regulated cytokine production and secretion, especially in macrophages and leukocytes, a major role of magnesium deficiency in alcohol-induced inflammatory processes can be envisioned. Considering all these various aspects together, it becomes apparent that magnesium loss may represent a predisposing factor to the onset of alcohol-induced pathologies including brain stroke, sarcopenia, cardiomyopathy, steatohepatitis and cirrhosis. The present review will attempt to clarify some of the mechanisms by which ethanol impairs magnesium transport and homeostasis in brain, brain vasculature, skeletal muscle, heart and liver cells, as a first step towards more mechanistic studies aimed at relating magnesium loss with the incurrence of short- and long-term ethanol-induced complications in these organs.

  9. IFCC guideline for sampling, measuring and reporting ionized magnesium in plasma

    DEFF Research Database (Denmark)

    Rayana, M.C. Ben; Burnett, R.W.; Covington, A.K.

    2008-01-01

    of magnesium in primary aqueous calibrants with magnesium, sodium, and calcium chloride of physiological ionic strength. The recommended name is "the concentration of ionized magnesium in plasma". Based on this guideline, results will be approximately 3% higher than the true substance concentration and 4......Analyzers with ion-selective electrodes (ISEs) for ionized magnesium (iMg) should yield comparable and unbiased results for iMg. This IFCC guideline on sampling, measuring and reporting iMg in plasma provides a prerequisite to achieve this goal [in this document, "plasma" refers to circulating...... plasma and the forms in which it is sampled, namely the plasma phase of anticoagulated whole blood (or "blood"), plasma separated from blood cells, or serum]. The guideline recommends measuring and reporting ionized magnesium as a substance concentration relative to the substance concentration...

  10. The Effects of High Level Magnesium Dialysis/Substitution Fluid on Magnesium Homeostasis under Regional Citrate Anticoagulation in Critically Ill.

    Directory of Open Access Journals (Sweden)

    Mychajlo Zakharchenko

    Full Text Available The requirements for magnesium (Mg supplementation increase under regional citrate anticoagulation (RCA because citrate acts by chelation of bivalent cations within the blood circuit. The level of magnesium in commercially available fluids for continuous renal replacement therapy (CRRT may not be sufficient to prevent hypomagnesemia.Patients (n = 45 on CRRT (2,000 ml/h, blood flow (Qb 100 ml/min with RCA modality (4% trisodium citrate using calcium free fluid with 0.75 mmol/l of Mg with additional magnesium substitution were observed after switch to the calcium-free fluid with magnesium concentration of 1.50 mmol/l (n = 42 and no extra magnesium replenishment. All patients had renal indications for CRRT, were treated with the same devices, filters and the same postfilter ionized calcium endpoint (<0.4 mmol/l of prefilter citrate dosage. Under the high level Mg fluid the Qb, dosages of citrate and CRRT were consequently escalated in 9h steps to test various settings.Median balance of Mg was -0.91 (-1.18 to -0.53 mmol/h with Mg 0.75 mmol/l and 0.2 (0.06-0.35 mmol/h when fluid with Mg 1.50 mmol/l was used. It was close to zero (0.02 (-0.12-0.18 mmol/h with higher blood flow and dosage of citrate, increased again to 0.15 (-0.11-0.25 mmol/h with 3,000 ml/h of high magnesium containing fluid (p<0.001. The arterial levels of Mg were mildly increased after the change for high level magnesium containing fluid (p<0.01.Compared to ordinary dialysis fluid the mildly hypermagnesemic fluid provided even balances and adequate levels within ordinary configurations of CRRT with RCA and without a need for extra magnesium replenishment.ClinicalTrials.gov Identifier: NCT01361581.

  11. Myth or Reality?Transdermal Magnesium?

    OpenAIRE

    Gr?ber, Uwe; Werner, Tanja; Vormann, J?rgen; Kisters, Klaus

    2017-01-01

    In the following review, we evaluated the current literature and evidence-based data on transdermal magnesium application and show that the propagation of transdermal magnesium is scientifically unsupported. The importance of magnesium and the positive effects of magnesium supplementation are extensively documented in magnesium deficiency, e.g., cardiovascular disease and diabetes mellitus. The effectiveness of oral magnesium supplementation for the treatment of magnesium deficiency has been ...

  12. Magnesium substitution in brushite cements for enhanced bone tissue regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Cabrejos-Azama, Jatsue, E-mail: jacaza@farm.ucm.es [Departamento de Química-Física II, Facultad de Farmacia, UCM, Madrid (Spain); Departamento de Estomatología III, Facultad de Odontología UCM, Madrid (Spain); Alkhraisat, Mohammad Hamdan; Rueda, Carmen [Departamento de Química-Física II, Facultad de Farmacia, UCM, Madrid (Spain); Torres, Jesús [Facultad de Ciencias de la salud URJC, Alcorcón, Madrid (Spain); Blanco, Luis [Departamento de Estomatología III, Facultad de Odontología UCM, Madrid (Spain); López-Cabarcos, Enrique [Departamento de Química-Física II, Facultad de Farmacia, UCM, Madrid (Spain)

    2014-10-01

    We have synthesized calcium phosphate cements doped with different amounts of magnesium (Mg-CPC) with a twofold purpose: i) to evaluate in vitro the osteoblast cell response to this material, and ii) to compare the bone regeneration capacity of the doped material with a calcium cement prepared without magnesium (CPC). Cell proliferation and in vivo response increased in the Mg-CPCs in comparison with CPC. The Mg-CPCs have promoted higher new bone formation than the CPC (p < 0.05). The cytocompatibility and histomorfometric analysis performed in the rabbit calvaria showed that the incorporation of magnesium ions in CPC improves osteoblasts proliferation and provides higher new bone formation. The development of a bone substitute with controllable biodegradable properties and improved bone regeneration can be considered a step toward personalized therapy that can adapt to patient needs and clinical situations. - Highlights: • The Mg-CPCs promote higher new bone formation than the CPC. • The incorporation of magnesium ions in CPC improves osteoblasts proliferation. • Mg-CPC is a bone substitute with controllable biodegradable properties. • We suggest that the use of Mg ions could improve the clinical efficiency of CPCs.

  13. Study on the bonding strength between calcium phosphate/chitosan composite coatings and a Mg alloy substrate

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Jie [School of Chemistry Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Pharmacy College, Jiamusi University, Jiamusi 154007 (China); Dai Changsong, E-mail: changsd@hit.edu.cn [School of Chemistry Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Wei Jie [School of Chemistry Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); School of Chemistry and Bioengineering, Suzhou Science Technology University, Suzhou 215009 (China); Wen Zhaohui, E-mail: wenzhaohui1968@163.com [Department of Neuro intern, First Affiliated Hospital of Harbin Medical University, Harbin 150001 (China)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer Calcium phosphate/chitosan composite coatings on the MAO-AZ91D alloy were prepared. Black-Right-Pointing-Pointer The bonding force between the coating and the magnesium alloy was optimized. Black-Right-Pointing-Pointer The composite coating slowed down the corrosion rate of magnesium alloy in m-SBF. - Abstract: In order to improve the bonding strength between calcium phosphate/chitosan composite coatings and a micro-arc oxidized (MAO)-AZ91D Mg alloy, different influencing parameters were investigated in the process of electrophoretic deposition (EPD) followed by conversion in a phosphate buffer solution (PBS). Surface morphology and phase constituents of the as-prepared materials were investigated by using X-ray diffractometer (XRD), Fourier-transformed infrared spectrophotometer (FTIR), Raman spectrometer, scanning electron microscope (SEM) with an energy dispersive spectrometer (EDS), and a thermo gravimetric and differential thermal analyzer (TG-DTA). Scratch tests were carried out to study the bonding properties between the coatings and the substrates. In vitro immersion tests were conducted to determine the corrosion behaviors of samples with and without deposit layers through electrochemical experiments. In the EPD process, the acetic acid content in the electrophoresis suspension and the electrophoretic voltage played important roles in improving the bonding properties, while the contents of chitosan (CS) and nano-hydroxyapatite (nHA, Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2}) in the suspension had less significant influences on the mechanical bonding strength. It was observed that the coatings showed the excellent bonding property when an electrophoretic voltage was in a range of 40-110 V with other reagent amounts as follows: acetic acid: 4.5 vol.%, CS {<=} 0.25 g, nHA {<=} 2.0 g in 200 ml of a CS-acetic acid aqueous solution and nHA {<=} 2.5 g in 300 ml of absolute ethanol. The morphology of the composite coating

  14. Functional Effects of Prebiotic Fructans in Colon Cancer and Calcium Metabolism in Animal Models

    National Research Council Canada - National Science Library

    Rivera-Huerta, Marisol; Lizárraga-Grimes, Vania Lorena; Castro-Torres, Ibrahim Guillermo; Tinoco-Méndez, Mabel; Macías-Rosales, Lucía; Sánchez-Bartéz, Francisco; Tapia-Pérez, Graciela Guadalupe; Romero-Romero, Laura; Gracia-Mora, María Isabel

    2017-01-01

      Inulin-type fructans are polymers of fructose molecules and are known for their capacity to enhance absorption of calcium and magnesium, to modulate gut microbiota and energy metabolism, and to improve glycemia...

  15. 21 CFR 184.1425 - Magnesium carbonate.

    Science.gov (United States)

    2010-04-01

    ... a solution of magnesium sulfate or by carbonation of a slurry of magnesium hydroxide followed by... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium carbonate. 184.1425 Section 184.1425 Food... Specific Substances Affirmed as GRAS § 184.1425 Magnesium carbonate. (a) Magnesium carbonate (molecular...

  16. EFFECT OF LEAD ACETATE

    African Journals Online (AJOL)

    MICROSOFT

    The project was conducted to evaluate the effect of lead administered as lead acetate at different dosage levels via drinking water in broiler chicks. Thirty-five healthy chicks were divided into seven groups (five chicks each) and one group was kept as un-medicated control. Groups A, B, C, D, E and F were medicated with ...

  17. furfural and acetic acid

    African Journals Online (AJOL)

    Investigating the effects of two lignocellulose degradation by-products (furfural and acetic acid) on ethanol fermentations by six ethanologenic yeast strains. ... Among the tested yeast strains, 1300 exhibited the highest growth rate, thus can be a promising candidate for mass production of bioethanol. Three important ...

  18. Variações nos teores de potássio, cálcio e magnésio em capim-marandu adubado com doses de nitrogênio e de enxofre Alterations in potassium, calcium and magnesium concentrations in marandu palisadegrass fertilized with nitrogen and sulfur rates

    Directory of Open Access Journals (Sweden)

    Karina Batista

    2010-02-01

    Full Text Available O uso eficiente da pastagem, em sistemas intensivos de produção, é dependente de nutrição balanceada da planta forrageira. Objetivou-se neste trabalho avaliar as variações nos teores de K, Ca e Mg em Brachiaria brizantha cv. Marandu, cultivada em Neossolo Quartzarênico, em função de doses de N e de S. O experimento foi conduzido em casa de vegetação, em Piracicaba-SP, no período de dezembro de 2004 a abril de 2005. Adotou-se o delineamento de blocos casualizados em esquema fatorial fracionado 5 x 5, com 13 combinações das doses de N e S e quatro repetições. Utilizaram-se como unidades experimentais vasos com 3,6 dm³ de solo e cinco plantas de capim-marandu. Foram realizados três cortes nas plantas e, em cada um deles, foram separadas as frações da parte aérea. A adubação com N interferiu nos teores de Ca e de Mg, bem como nas proporções de K, Ca e Mg na parte aérea do capim-marandu. As aplicações conjuntas de N e S influenciaram negativamente o teor de K nas folhas diagnósticas desse capim. A aplicação de N e de S no solo para a implantação do capim-marandu alterou o balanço nutricional em Ca, Mg e K, na planta.Alterations in Potassium, Calcium and Magnesium Concentrations in Marandu Palisadegrass Fertilized with Nitrogen and Sulfur Rates An efficient pasture use in intensive production systems depends on the balanced mineral nutrition of the forage plant. Our objective was to evaluate changes in potassium, calcium and magnesium concentrations of Brachiaria brizantha, cv. Marandu grown on an Entisol with nitrogen and sulfur rates. The experiment was carried out in a greenhouse, in Piracicaba, State of São Paulo, from December 2004 to April 2005. A randomized block design was used in a fractionated 5 x 5 factorial design with 13 N and S rate combinations. The experimental units consisted of 3.6 dm-3 plastic pots containing five Marandu plants. The grass plants were harvested three times and the shoot and its

  19. Magnesium for Hydrogen Storage

    DEFF Research Database (Denmark)

    Pedersen, Allan Schrøder; Kjøller, John; Larsen, B.

    1983-01-01

    A study of the hydrogenation characteristics of fine magnesium powder during repeated cycling has been performed using a high-pressure microbalance facility. No effect was found from the cycling regarding kinetics and storage capacity. The reaction rate of the absorption process was fast at tempe......A study of the hydrogenation characteristics of fine magnesium powder during repeated cycling has been performed using a high-pressure microbalance facility. No effect was found from the cycling regarding kinetics and storage capacity. The reaction rate of the absorption process was fast...... at temperatures around 600 K and above, but the reversed reaction showed somewhat slower kinetics around 600 K. At higher temperatures the opposite was found. The enthalpy and entropy change by the hydrogenation, derived from pressure-concentration isotherms, agree fairly well with those reported earlier....

  20. Cellular magnesium homeostasis.

    Science.gov (United States)

    Romani, Andrea M P

    2011-08-01

    Magnesium, the second most abundant cellular cation after potassium, is essential to regulate numerous cellular functions and enzymes, including ion channels, metabolic cycles, and signaling pathways, as attested by more than 1000 entries in the literature. Despite significant recent progress, however, our understanding of how cells regulate Mg(2+) homeostasis and transport still remains incomplete. For example, the occurrence of major fluxes of Mg(2+) in either direction across the plasma membrane of mammalian cells following metabolic or hormonal stimuli has been extensively documented. Yet, the mechanisms ultimately responsible for magnesium extrusion across the cell membrane have not been cloned. Even less is known about the regulation in cellular organelles. The present review is aimed at providing the reader with a comprehensive and up-to-date understanding of the mechanisms enacted by eukaryotic cells to regulate cellular Mg(2+) homeostasis and how these mechanisms are altered under specific pathological conditions. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Influence of calcium sources on microbially induced calcium carbonate precipitation by Bacillus sp. CR2.

    Science.gov (United States)

    Achal, Varenyam; Pan, Xiangliang

    2014-05-01

    Stimulation of microbially induced calcium carbonate precipitation (MICCP) is likely to be influenced by calcium sources. In order to study such influences, we performed MICCP using Bacillus sp. CR2 in nutrient broth containing urea, supplemented with different calcium sources (calcium chloride, calcium oxide, calcium acetate and calcium nitrate). The experiment lasted 7 days, during which bacterial growth, urease activity, calcite production and pH were measured. Our results showed that calcium chloride is the better calcium source for MICCP process, since it provides higher urease activity and more calcite production. The influences of calcium sources on MICCP were further studied using Fourier transform-infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. These analyses confirmed that the precipitate formed was CaCO3 and composed of predominantly calcite crystals with a little amount of aragonite and vaterite crystals. The maximum yield of calcite precipitation was achievable with calcium chloride followed by calcium nitrate as a calcium source. The results of present study may be applicable to media preparation during efficient MICCP process.

  2. Magnesium in Prevention and Therapy.

    Science.gov (United States)

    Gröber, Uwe; Schmidt, Joachim; Kisters, Klaus

    2015-09-23

    Magnesium is the fourth most abundant mineral in the body. It has been recognized as a cofactor for more than 300 enzymatic reactions, where it is crucial for adenosine triphosphate (ATP) metabolism. Magnesium is required for DNA and RNA synthesis, reproduction, and protein synthesis. Moreover, magnesium is essential for the regulation of muscular contraction, blood pressure, insulin metabolism, cardiac excitability, vasomotor tone, nerve transmission and neuromuscular conduction. Imbalances in magnesium status-primarily hypomagnesemia as it is seen more common than hypermagnesemia-might result in unwanted neuromuscular, cardiac or nervous disorders. Based on magnesium's many functions within the human body, it plays an important role in prevention and treatment of many diseases. Low levels of magnesium have been associated with a number of chronic diseases, such as Alzheimer's disease, insulin resistance and type-2 diabetes mellitus, hypertension, cardiovascular disease (e.g., stroke), migraine headaches, and attention deficit hyperactivity disorder (ADHD).

  3. Magnesium in Prevention and Therapy

    OpenAIRE

    Uwe Gröber; Joachim Schmidt; Klaus Kisters

    2015-01-01

    Magnesium is the fourth most abundant mineral in the body. It has been recognized as a cofactor for more than 300 enzymatic reactions, where it is crucial for adenosine triphosphate (ATP) metabolism. Magnesium is required for DNA and RNA synthesis, reproduction, and protein synthesis. Moreover, magnesium is essential for the regulation of muscular contraction, blood pressure, insulin metabolism, cardiac excitability, vasomotor tone, nerve transmission and neuromuscular conduction. Imbalances ...

  4. Differential magnesium implant corrosion coat formation and contribution to bone bonding.

    Science.gov (United States)

    Rahim, Muhammad Imran; Weizbauer, Andreas; Evertz, Florian; Hoffmann, Andrea; Rohde, Manfred; Glasmacher, Birgit; Windhagen, Henning; Gross, Gerhard; Seitz, Jan-Marten; Mueller, Peter P

    2017-03-01

    Magnesium alloys are presently under investigation as promising biodegradable implant materials with osteoconductive properties. To study the molecular mechanisms involved, the potential contribution of soluble magnesium corrosion products to the stimulation of osteoblastic cell differentiation was examined. However, no evidence for the stimulation of osteoblast differentiation could be obtained when cultured mesenchymal precursor cells were differentiated in the presence of metallic magnesium or in cell culture medium containing elevated magnesium ion levels. Similarly, in soft tissue no bone induction by metallic magnesium or by the corrosion product magnesium hydroxide could be observed in a mouse model. Motivated by the comparatively rapid accumulation solid corrosion products physicochemical processes were examined as an alternative mechanism to explain the stimulation of bone growth by magnesium-based implants. During exposure to physiological solutions a structured corrosion coat formed on magnesium whereby the elements calcium and phosphate were enriched in the outermost layer which could play a role in the established biocompatible behavior of magnesium implants. When magnesium pins were inserted into avital bones, corrosion lead to increases in the pull out force, suggesting that the expanding corrosion layer was interlocking with the surrounding bone. Since mechanical stress is a well-established inducer of bone growth, volume increases caused by the rapid accumulation of corrosion products and the resulting force development could be a key mechanism and provide an explanation for the observed stimulatory effects of magnesium-based implants in hard tissue. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 697-709, 2017. © 2016 Wiley Periodicals, Inc.

  5. Ulipristal acetate: in uterine fibroids.

    Science.gov (United States)

    Croxtall, Jamie D

    2012-05-28

    Ulipristal acetate, a selective progesterone-receptor modulator, inhibits the proliferation and induces apoptosis of leiomyoma cells in vitro. It also modulates the expression of vascular endothelial growth factors and hormone receptors and modulates extracellular matrix breakdown in leiomyoma cells but not in myometrial cells. In two randomized, double-blind, multinational phase III trials of 13 weeks' duration in women aged 18-50 years with uterine fibroids, a once-daily regimen of oral ulipristal acetate 5 mg/day controlled excessive uterine bleeding (primary endpoint) in ≥90% of patients. Ulipristal acetate 5 mg/day was more effective than placebo and was shown to be noninferior to intramuscular leuprolide acetate 3.75 mg once monthly in controlling uterine bleeding. Uterine bleeding was rapidly controlled by ulipristal acetate. Approximately half of recipients of ulipristal acetate 5 mg/day became amenorrhoeic within the first 10 days of treatment. Furthermore, uterine bleeding was controlled significantly more rapidly for recipients of ulipristal acetate than recipients of leuprolide acetate. A significantly greater median reduction from baseline in total fibroid volume was observed for recipients of ulipristal acetate 5 mg once daily than recipients of placebo following 13 weeks' treatment (coprimary endpoint). For patients who did not undergo surgery, the volume reduction was maintained for at least 6 months after discontinuing treatment. Ulipristal acetate was generally well tolerated in women with uterine fibroids. The incidence of hot flush occurred with a significantly lower frequency for recipients of ulipristal acetate than for recipients of leuprolide acetate.

  6. Function of magnesium aluminate hydrate and magnesium nitrate ...

    Indian Academy of Sciences (India)

    MgO was added both as spinel (MgAl2O4) forming precursor i.e. magnesium aluminate hydrate, and magnesium nitrate. Sintering investigations were conducted in the temperature range 1500–1600°C with 2 h soaking. Structural study of sintered pellets was carried out by extensive XRD analysis. Scanning electron mode ...

  7. Function of magnesium aluminate hydrate and magnesium nitrate ...

    Indian Academy of Sciences (India)

    Administrator

    Abstract. Chemically pure reactive alumina (α-Al2O3) which is commercially available was used for densifi- cation study in presence of widely accepted dopant MgO as additive. MgO was added both as spinel. (MgAl2O4) forming precursor i.e. magnesium aluminate hydrate, and magnesium nitrate. Sintering investiga-.

  8. The effect of calcium on auxin depletion-induced tomato ...

    African Journals Online (AJOL)

    Indole-3-acetic acid (IAA) and calcium are the most important factors that instigate plant organ abscission. This study aimed to elucidate the mechanisms that underlie the effects of IAA and calcium on delayed abscission in tomato. The results showed a clear trend towards reduced abscission rates with increased ...

  9. REGIOSELECTIVE REACTIONS OF 3-ALKYL-1-PHENYL-2-PYRAZOLIN-5-ONES WITH ACYL HALIDES IN THE PRECENCE OF NONOSIZED MAGNESIUM HYDROXIDE AS A HIGHLY EFFECTIVE HETEROGENOUS BASE CATALYST Regioselektive Reaktionen von 3-Alkyl-1-PHENYL-2-pyrazolin-5-ONES Mit Acylhalogeniden IN DER PRECENCE DER NONOSIZED MAGNESIUM HYDROXIDE als hochwirksame heterogene BASE CATALYST

    OpenAIRE

    Hassan Sheibani and Bahman Massomi Nejad

    2012-01-01

    4-Acyl-3-alkyl-1-phenyl-2-pyrazolin-5-one derivatives were prepared by the regioselective acylation of 3-alkyl-1-phenyl-2-pyrazolin-5-ones in the presence of base catalysts such as calcium hydroxide [Ca(OH)2], magnesium hydroxide [Mg(OH)2] and nanosized magnesium hydroxide. In the presence of nanosized magnesium hydroxide, excellent yields of products were obtained and reaction times were significantly reduced.

  10. Selective Laser Melting of Magnesium and Magnesium Alloys

    Science.gov (United States)

    Gieseke, Matthias; Noelke, Christian; Kaierle, Stefan; Wesling, Volker; Haferkamp, Heinz

    Selective Laser Melting (SLM) offers the possibility to create three dimensional parts by having full freedom of design. Therefore prototypes can be produced faster and conventionally manufactured parts can be shaped individually, including an optimized design regarding potential loads and parts weight. The manufacturing of biocompatible metals like 316L and TiA16V4 is already industrially established. Because of the corrosive and mechanical properties of magnesium and the advantages of the SLM process, using magnesium is of great interest for manufacturing individual biodegradable implants. Recent investigations on SLM of magnesium have not led to successful operation so far. Due to the low vaporizing temperature, manufacturing non-porous and three dimensional parts from magnesium was not possible yet. Following a new strategy, using an industrial SLM system with an overpressure building chamber, investigations on SLM of magnesium are now carried out in order to overcome these difficulties and produce fully dense three dimensional parts.

  11. Magnesium Hall Thruster

    Science.gov (United States)

    Szabo, James J.

    2015-01-01

    This Phase II project is developing a magnesium (Mg) Hall effect thruster system that would open the door for in situ resource utilization (ISRU)-based solar system exploration. Magnesium is light and easy to ionize. For a Mars- Earth transfer, the propellant mass savings with respect to a xenon Hall effect thruster (HET) system are enormous. Magnesium also can be combusted in a rocket with carbon dioxide (CO2) or water (H2O), enabling a multimode propulsion system with propellant sharing and ISRU. In the near term, CO2 and H2O would be collected in situ on Mars or the moon. In the far term, Mg itself would be collected from Martian and lunar regolith. In Phase I, an integrated, medium-power (1- to 3-kW) Mg HET system was developed and tested. Controlled, steady operation at constant voltage and power was demonstrated. Preliminary measurements indicate a specific impulse (Isp) greater than 4,000 s was achieved at a discharge potential of 400 V. The feasibility of delivering fluidized Mg powder to a medium- or high-power thruster also was demonstrated. Phase II of the project evaluated the performance of an integrated, highpower Mg Hall thruster system in a relevant space environment. Researchers improved the medium power thruster system and characterized it in detail. Researchers also designed and built a high-power (8- to 20-kW) Mg HET. A fluidized powder feed system supporting the high-power thruster was built and delivered to Busek Company, Inc.

  12. Magnesium inhibits Wnt/β-catenin activity and reverses the osteogenic transformation of vascular smooth muscle cells.

    Science.gov (United States)

    Montes de Oca, Addy; Guerrero, Fatima; Martinez-Moreno, Julio M; Madueño, Juan A; Herencia, Carmen; Peralta, Alan; Almaden, Yolanda; Lopez, Ignacio; Aguilera-Tejero, Escolastico; Gundlach, Kristina; Büchel, Janine; Peter, Mirjam E; Passlick-Deetjen, Jutta; Rodriguez, Mariano; Muñoz-Castañeda, Juan R

    2014-01-01

    Magnesium reduces vascular smooth muscle cell (VSMC) calcification in vitro but the mechanism has not been revealed so far. This work used only slightly increased magnesium levels and aimed at determining: a) whether inhibition of magnesium transport into the cell influences VSMC calcification, b) whether Wnt/β-catenin signaling, a key mediator of osteogenic differentiation, is modified by magnesium and c) whether magnesium can influence already established vascular calcification. Human VSMC incubated with high phosphate (3.3 mM) and moderately elevated magnesium (1.4 mM) significantly reduced VSMC calcification and expression of the osteogenic transcription factors Cbfa-1 and osterix, and up-regulated expression of the natural calcification inhibitors matrix Gla protein (MGP) and osteoprotegerin (OPG). The protective effects of magnesium on calcification and expression of osteogenic markers were no longer observed in VSMC cultured with an inhibitor of cellular magnesium transport (2-aminoethoxy-diphenylborate [2-APB]). High phosphate induced activation of Wnt/β-catenin pathway as demonstrated by the translocation of β-catenin into the nucleus, increased expression of the frizzled-3 gene, and downregulation of Dkk-1 gene, a specific antagonist of the Wnt/β-catenin signaling pathway. The addition of magnesium however inhibited phosphate-induced activation of Wnt/β-catenin signaling pathway. Furthermore, TRPM7 silencing using siRNA resulted in activation of Wnt/β-catenin signaling pathway. Additional experiments were performed to test the ability of magnesium to halt the progression of already established VSMC calcification in vitro. The delayed addition of magnesium decreased calcium content, down-regulated Cbfa-1 and osterix and up-regulated MGP and OPG, when compared with a control group. This effect was not observed when 2-APB was added. In conclusion, magnesium transport through the cell membrane is important to inhibit VSMC calcification in vitro

  13. Electrolytes for magnesium electrochemical cells

    Energy Technology Data Exchange (ETDEWEB)

    Burrell, Anthony K.; Sa, Niya; Proffit, Danielle Lee; Lipson, Albert; Liao, Chen; Vaughey, John T.; Ingram, Brian J.

    2017-07-04

    An electrochemical cell includes a high voltage cathode configured to operate at 1.5 volts or greater; an anode including Mg.sup.0; and an electrolyte including an ether solvent and a magnesium salt; wherein: a concentration of the magnesium salt in the ether is 1 M or greater.

  14. Hydrostatic extrusion of magnesium alloys

    NARCIS (Netherlands)

    Sillekens, W.H.; Bohlen, J.

    2012-01-01

    This chapter deals with the capabilities and limitations of the hydrostatic extrusion process for the manufacturing of magnesium alloy sections. Firstly, the process basics for the hydrostatic extrusion of materials in general and of magnesium in particular are introduced. Next, some recent research

  15. [Magnesium homeostasis and its disturbances].

    Science.gov (United States)

    Nakai, Kentaro

    2012-08-01

    Magnesium homeostasis is maintained through normal functions of the kidney, intestine, and bone. In the kidney, approximately 80% magnesium is filtered by the glomeruli. In general, 95% filtered magnesium is collectively reabsorbed in the proximal tubule (15%-20%) , thick ascending limb of Henle (TAL, 65%-75%) , and the distal convoluted tubule (DCT, 5%-10%) . In the TAL, magnesium reabsorption regulated by the paracellular pathway via claudin-16 is driven by electrochemical voltage. Chloride channel Kb and renal outer medullary potassium channels control this lumen-positive voltage. In the DCT, the transcellular pathway via transient receptor potential melastatin 6 (TRPM6) plays a fundamental role in the final 5%-10% magnesium reabsorption. The functions of TRPM6 depend on Na-Cl co-transporters and Na( + )-K( + )-ATPase. Defects in these regulatory proteins may cause inherited or drug-induced disorders of magnesium metabolism. Recently, some proteins have been confirmed to be responsible for magnesium homeostasis ; however, further research is required to elucidate the mechanisms underlying the maintenance of magnesium homeostasis.

  16. Magnesium in Prevention and Therapy

    Directory of Open Access Journals (Sweden)

    Uwe Gröber

    2015-09-01

    Full Text Available Magnesium is the fourth most abundant mineral in the body. It has been recognized as a cofactor for more than 300 enzymatic reactions, where it is crucial for adenosine triphosphate (ATP metabolism. Magnesium is required for DNA and RNA synthesis, reproduction, and protein synthesis. Moreover, magnesium is essential for the regulation of muscular contraction, blood pressure, insulin metabolism, cardiac excitability, vasomotor tone, nerve transmission and neuromuscular conduction. Imbalances in magnesium status—primarily hypomagnesemia as it is seen more common than hypermagnesemia—might result in unwanted neuromuscular, cardiac or nervous disorders. Based on magnesium’s many functions within the human body, it plays an important role in prevention and treatment of many diseases. Low levels of magnesium have been associated with a number of chronic diseases, such as Alzheimer’s disease, insulin resistance and type-2 diabetes mellitus, hypertension, cardiovascular disease (e.g., stroke, migraine headaches, and attention deficit hyperactivity disorder (ADHD.

  17. Magnesium in Prevention and Therapy

    Science.gov (United States)

    Gröber, Uwe; Schmidt, Joachim; Kisters, Klaus

    2015-01-01

    Magnesium is the fourth most abundant mineral in the body. It has been recognized as a cofactor for more than 300 enzymatic reactions, where it is crucial for adenosine triphosphate (ATP) metabolism. Magnesium is required for DNA and RNA synthesis, reproduction, and protein synthesis. Moreover, magnesium is essential for the regulation of muscular contraction, blood pressure, insulin metabolism, cardiac excitability, vasomotor tone, nerve transmission and neuromuscular conduction. Imbalances in magnesium status—primarily hypomagnesemia as it is seen more common than hypermagnesemia—might result in unwanted neuromuscular, cardiac or nervous disorders. Based on magnesium’s many functions within the human body, it plays an important role in prevention and treatment of many diseases. Low levels of magnesium have been associated with a number of chronic diseases, such as Alzheimer’s disease, insulin resistance and type-2 diabetes mellitus, hypertension, cardiovascular disease (e.g., stroke), migraine headaches, and attention deficit hyperactivity disorder (ADHD). PMID:26404370

  18. Magnesium--essentials for anesthesiologists.

    Science.gov (United States)

    Herroeder, Susanne; Schönherr, Marianne E; De Hert, Stefan G; Hollmann, Markus W

    2011-04-01

    Magnesium plays a fundamental role in many cellular functions, and thus there is increasing interest in its role in clinical medicine. Although numerous experimental studies indicate positive effects of magnesium in a variety of disease states, large clinical trials often give conflicting results. However, there is clear evidence for magnesium to benefit patients with eclampsia or torsades de pointes arrhythmias. In addition, magnesium seems to have antinociceptive and anesthetic as well as neuroprotective effects, yet well-designed large clinical trials are required to determine its actual efficacy in pain management or in the state of stroke or subarachnoid hemorrhage. The current review aims to provide an overview of current knowledge and available evidence with respect to physiologic aspects of magnesium and proposed indications and recommendations for its use in the clinical setting.

  19. Serum magnesium and not vitamin D is associated with better QoL in COPD

    DEFF Research Database (Denmark)

    Hashim Ali Hussein, Sarah; Nielsen, Lars Peter; Dolberg, Mette K.Bøgebjerg

    2015-01-01

    BACKGROUND: Deficiency of serum levels of vitamin D3 (se vitD), magnesium (se Mg) and calcium (se Ca) may be associated with increased exacerbation risk in chronic obstructive pulmonary disease (COPD). However, associations with other aspects of COPD, e.g. lung function and quality of life (Qo...

  20. Larazotide acetate promotes tight junction assembly in epithelial cells.

    Science.gov (United States)

    Gopalakrishnan, Shobha; Tripathi, Amit; Tamiz, Amir P; Alkan, Sefik S; Pandey, Niranjan B

    2012-05-01

    Tight junctions (TJ) control paracellular permeability and apical-basolateral polarity of epithelial cells. Dysregulated permeability is associated with pathological conditions, such as celiac disease and inflammatory bowel disease. TJ formation is dependent on E-cadherin-mediated cell-cell adhesion and actin rearrangement, and is regulated by the Rho family GTPase and aPKC signaling pathways. Larazotide acetate, an 8-mer peptide and TJ modulator, inhibits TJ disassembly and dysfunction caused by endogenous and exogenous stimuli in intestinal epithelial cells. Here, we examined the effect of larazotide acetate on de novo TJ assembly using 2 different model systems. In MDCK cells, larazotide acetate promoted TJ assembly in a calcium switch assay. Larazotide acetate also promoted actin rearrangement, and junctional distribution of zonula occludens-1 (ZO-1), occludin, claudins, and E-cadherin. Larazotide acetate promoted TJ maturation and decreased paracellular permeability in "leaky" Caco-2 cells. Taken together, our data indicate that larazotide acetate enhances TJ assembly and barrier function by promoting actin rearrangement and redistribution of TJ and AJ proteins. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Electrophoretic deposition of magnesium silicates on titanium implants: Ion migration and silicide interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Afshar-Mohajer, M. [Center for Advanced Manufacturing and Material Processing, Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603 (Malaysia); Yaghoubi, A., E-mail: yaghoubi@siswa.um.edu.my [Center for High Impact Research, University of Malaya, Kuala Lumpur 50603 (Malaysia); Ramesh, S., E-mail: ramesh79@um.edu.my [Center for Advanced Manufacturing and Material Processing, Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603 (Malaysia); Bushroa, A.R.; Chin, K.M.C.; Tin, C.C. [Center for Advanced Manufacturing and Material Processing, Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603 (Malaysia); Chiu, W.S. [Low Dimensional Materials Research Center, Department of Physics, University of Malaya, Kuala Lumpur 50603 (Malaysia)

    2014-07-01

    Magnesium silicates (Mg{sub x}SiO{sub y}) and in particular forsterite (Mg{sub 2}SiO{sub 4}) owing to their low thermal expansion mismatch with metals are promising materials for bioactive coating of implants. Here, we report the electrophoretic deposition (EPD) of forsterite onto titanium substrates using different precursors. Unlike bulk samples which achieve full stoichiometry only beyond 1400 °C, non-stoichiometric magnesium silicate rapidly decomposes into magnesium oxide nanowires during sintering. Elemental mapping and X-ray diffraction suggest that oxygen diffusion followed by ion exchange near the substrate leads to formation of an interfacial Ti{sub 5}Si{sub 3} layer. Pre-annealed forsterite powder on the other hand shows a comparatively lower diffusion rate. Overall, magnesium silicate coatings do not exhibit thermally induced microcracks upon sintering as opposed to calcium phosphate bioceramics which are currently in use.

  2. Extractive process for preparing high purity magnesium chloride hexahydrate

    Directory of Open Access Journals (Sweden)

    Fezei Radouanne

    2012-01-01

    Full Text Available This paper refers a method for the preparation of magnesium chloride hexahydrate (bischofite from Sebkha el Melah of Zarzis Tunisian natural brine. It is a five-stage process essentially based on crystallization by isothermal evaporation and chemical precipitation. The two first steps were dedicated to the crystallization of sodium chloride and potassiummagnesium double salts, respectively. Then, the resulting liquor was desulfated using calcium chloride solution. After that another isothermal evaporation stage was implemented in order to eliminate potassium ions in the form of carnallite, KCl.MgCl2.6H2O. At the end of this step, the recovered solution primarily composed of magnesium and chloride ions was treated by dioxan in order to precipitate magnesium chloride as MgCl2.6H2O.C4H8O2. This compound dried at constant temperature of 100°C gave good quality magnesium chloride hexahydrate. Besides this salt, the various by-products obtained from the different treatment stages are also useful.

  3. Elevated dietary magnesium during pregnancy and postnatal life prevents ectopic mineralization in Enpp1asj mice, a model for generalized arterial calcification of infancy.

    Science.gov (United States)

    Kingman, Joshua; Uitto, Jouni; Li, Qiaoli

    2017-06-13

    Generalized arterial calcification of infancy (GACI) is an autosomal recessive disorder caused by mutations in the ENPP1 gene. It is characterized by mineralization of the arterial blood vessels, often diagnosed prenatally, and associated with death in early childhood. There is no effective treatment for this devastating disorder. We previously characterized the Enpp1asjmutant mouse as a model of GACI, and we have now explored the effect of elevated dietary magnesium (five-fold) in pregnant mothers and continuing for the first 14 weeks of postnatal life. The mothers were kept on either control diet or experimental diet supplemented with magnesium. Upon weaning at 4 weeks of age the pups were placed either on control diet or high magnesium diet. The degree of mineralization was assessed at 14 weeks of age by histopathology and a chemical calcium assay in muzzle skin, kidney and aorta. Mice placed on high magnesium diet showed little, if any, evidence of mineralization when their corresponding mothers were also placed on diet enriched with magnesium during pregnancy and nursing. The reduced ectopic mineralization in these mice was accompanied by increased calcium and magnesium content in the urine, suggesting that magnesium competes calcium-phosphate binding thereby preventing the mineral deposition. These results have implications for dietary management of pregnancies in which the fetus is suspected of having GACI. Moreover, augmenting a diet with high magnesium may be beneficial for other ectopic mineralization diseases, including nephrocalcinosis.

  4. Calcium Electroporation

    DEFF Research Database (Denmark)

    Frandsen, Stine Krog; Gibot, Laure; Madi, Moinecha

    2015-01-01

    BACKGROUND: Calcium electroporation describes the use of high voltage electric pulses to introduce supraphysiological calcium concentrations into cells. This promising method is currently in clinical trial as an anti-cancer treatment. One very important issue is the relation between tumor cell kill...... efficacy-and normal cell sensitivity. METHODS: Using a 3D spheroid cell culture model we have tested the effect of calcium electroporation and electrochemotherapy using bleomycin on three different human cancer cell lines: a colorectal adenocarcinoma (HT29), a bladder transitional cell carcinoma (SW780......), and a breast adenocarcinoma (MDA-MB231), as well as on primary normal human dermal fibroblasts (HDF-n). RESULTS: The results showed a clear reduction in spheroid size in all three cancer cell spheroids three days after treatment with respectively calcium electroporation (p

  5. Magnesium deficiency: What is our status

    Science.gov (United States)

    Low magnesium intake has been implicated in a broad range of cardiometabolic conditions, including diabetes, hypertension, and cardiovascular disease. Dietary magnesium and total body magnesium status have a widely-used but imperfect biomarker in serum magnesium. Despite serum magnesium’s limitation...

  6. Mineral resource of the month: magnesium

    Science.gov (United States)

    Kramer, Deborah A.

    2012-01-01

    Magnesium is the eighthmost abundant element in Earth’s crust, and the second-most abundant metal ion in seawater. Although magnesium is found in more than 60 minerals, only brucite, dolomite, magnesite and carnallite are commercially important for their magnesium content. Magnesium and its compounds also are recovered from seawater, brines found in lakes and wells, and bitterns (salts).

  7. 21 CFR 184.1426 - Magnesium chloride.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium chloride. 184.1426 Section 184.1426 Food... Specific Substances Affirmed as GRAS § 184.1426 Magnesium chloride. (a) Magnesium chloride (MgC12·6H2O, CAS... hydrochloric acid solution and crystallizing out magnesium chloride hexahydrate. (b) The ingredient meets the...

  8. 21 CFR 184.1431 - Magnesium oxide.

    Science.gov (United States)

    2010-04-01

    ... powder (light) or a relatively dense white powder (heavy) by heating magnesium hydroxide or carbonate... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium oxide. 184.1431 Section 184.1431 Food and... Substances Affirmed as GRAS § 184.1431 Magnesium oxide. (a) Magnesium oxide (MgO, CAS Reg. No. 1309-48-4...

  9. 21 CFR 184.1443 - Magnesium sulfate.

    Science.gov (United States)

    2010-04-01

    ... magnesium oxide, hydroxide, or carbonate with sulfuric acid and evaporating the solution to crystallization... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium sulfate. 184.1443 Section 184.1443 Food... Specific Substances Affirmed as GRAS § 184.1443 Magnesium sulfate. (a) Magnesium sulfate (MgSO4·7H2O, CAS...

  10. 21 CFR 184.1428 - Magnesium hydroxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium hydroxide. 184.1428 Section 184.1428 Food... Specific Substances Affirmed as GRAS § 184.1428 Magnesium hydroxide. (a) Magnesium hydroxide (Mg(OH)2, CAS... a white precipitate by the addition of sodium hydroxide to a water soluble magnesium salt or by...

  11. [Magnesium deficiency and stress: Issues of their relationship, diagnostic tests, and approaches to therapy].

    Science.gov (United States)

    Tarasov, E A; Blinov, D V; Zimovina, U V; Sandakova, E A

    2015-01-01

    Magnesium plays an important role in the functions of the central nervous system. It takes part in the regulation of the cell membrane, the transmembrane transport of calcium and sodium ions, and metabolic reactions that produce, accumulate, transfer, and utilize energy, free radicals, and their oxidation products. The magnesium-containing substances include many sequestered antigens, such as glial fibrillary acidic protein, S100, and neuron-specific enolase; magnesium may act as a neuroprotector that is able to modulate the regulation of blood-brain barrier permeability. Investigations have demonstrated a relationship between the manifestations of stress reactions (anxiety, autonomic dysfunction, and maladjustment) and magnesium deficiency (MD). Thus, mental and physical stresses cause an increase in magnesium elimination from the body. MD in turn enhances a response to stress, by paradoxically aggravating its sequels. Compensation for MD increases the ability of the nervous system to resist stress. The valid diagnosis of MD present difficulties; namely, a blood magnesium concentration decrease below 0.8 mmol/l is evidence of MD; but the constant blood level of magnesium may be long maintained due to its release from the bone tissue depot. So it is necessary to keep in mind the clinical manifestations of MD. The authors have developed and tested a simple rapid MD assessment test and a stress resistance self-rating test. The proposed tests will help to screen stress resistance and MD in outpatient settings.

  12. A new electrolytic magnesium production process

    Science.gov (United States)

    Sharma, Ram A.

    1996-10-01

    In this article, existing magnesium chloride electrolysis and thermal magnesium oxide reduction processes for producing magnesium are described and their limitations are pointed out. The theoretical background of a patented new process is outlined. In this process, magnesium oxide is dissolved in a rare-earth-chloride-containing electrolyte and electrolyzed to produce magnesium and oxygen like that of alumina in the Hall-Héroult process. It is also shown that the efficiency of the existing magnesium chloride electrolysis process should be improved greatly by adding a rare-earth chloride. In both cases, the magnesium produced is expected to be free from detrimental iron, nickel, copper, and boron impurities.

  13. Acidic Fluids Across Mars: Detections of Magnesium-Nickel Sulfates

    Science.gov (United States)

    Yen, A. S.; Ming, D. W.; Gellert, R.; Mittlefehldt, D. W.; Rampe, E. B.; Vaniman, D. T.; Thompson, L. M.; Morris, R. V.; Clark, B. C.; VanBommel, S. J.

    2017-01-01

    Calcium, magnesium and ferric iron sulfates have been detected by the instrument suites on the Mars rovers. A subset of the magnesium sulfates show clear associations with nickel. These associations indicate Ni(2+) co-precipitation with or substitution for Mg(2+) from sulfate-saturated solutions. Nickel is ex-tracted from primary rocks almost exclusively at pH values less than 6, constraining the formation of these Mg-Ni sulfates to mildly to strongly acidic conditions. There is clear evidence for aqueous alteration at the rim of Endeavour Crater (Meridiani Planum), in the Murray formation mudstone (Gale Crater), and near Home Plate (Gusev Crater). The discovery of Mg-Ni sulfates at these locations indicates a history of fluid-rock interactions at low pH.

  14. Antibiofilm Properties of Acetic Acid

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Alhede, Morten; Jensen, Peter Østrup

    2014-01-01

    of the infected implant, tissue, or organ and thereby the biofilm. Acetic acid is known for its antimicrobial effect on bacteria in general, but has never been thoroughly tested for its efficacy against bacterial biofilms. In this article, we describe complete eradication of both Gram-positive and Gram......-negative biofilms using acetic acid both as a liquid and as a dry salt. In addition, we present our clinical experience of acetic acid treatment of chronic wounds. In conclusion, we here present the first comprehensive in vitro and in vivo testing of acetic acid against bacterial biofilms....

  15. ACETIC ACID AND A BUFFER

    DEFF Research Database (Denmark)

    2009-01-01

    The present invention relates to a composition comprising : a) 0.01-20% wt/wt acetic acid and b) a physiologically tolerable buffer capable of maintaining acetic acid at a pH in the range of 2-7; and use of such a composition as an antimicrobial agent.......The present invention relates to a composition comprising : a) 0.01-20% wt/wt acetic acid and b) a physiologically tolerable buffer capable of maintaining acetic acid at a pH in the range of 2-7; and use of such a composition as an antimicrobial agent....

  16. Magnesium alloys and graphite wastes encapsulated in cementitious materials: Reduction of galvanic corrosion using alkali hydroxide activated blast furnace slag

    Energy Technology Data Exchange (ETDEWEB)

    Chartier, D., E-mail: david.chartier@cea.fr [Commissariat à l' Energie Atomique et aux Energies Alternatives, CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze (France); Muzeau, B. [DEN-Service d’Etude du Comportement des Radionucléides (SECR), CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France); Stefan, L. [AREVA NC/D& S - France/Technical Department, 1 place Jean Millier 92084 Paris La Défense (France); Sanchez-Canet, J. [Commissariat à l' Energie Atomique et aux Energies Alternatives, CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze (France); Monguillon, C. [DEN-Service d’Etude du Comportement des Radionucléides (SECR), CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France)

    2017-03-15

    Highlights: • Embedded in cement, magnesium is corroded by residual water present in porosity of the matrix. • Corrosion is enhanced by galvanic phenomenon when magnesium is in contact with graphite. • Galvanic corrosion of magnesium in contact with graphite debris is shown to be severe with ordinary Portland cement. • Galvanic corrosion is significantly lowered in high alkali medium such as sodium hydroxide. • Sodium hydroxide activated blast furnace slag is a convenient binder to embed magnesium. - Abstract: Magnesium alloys and graphite from spent nuclear fuel have been stored together in La Hague plant. The packaging of these wastes is under consideration. These wastes could be mixed in a grout composed of industrially available cement (Portland, calcium aluminate…). Within the alkaline pore solution of these matrixes, magnesium alloys are imperfectly protected by a layer of Brucite resulting in a slow corrosion releasing hydrogen. As the production of this gas must be considered for the storage safety, and the quality of wasteform, it is important to select a cement matrix capable of lowering the corrosion kinetics. Many types of calcium based cements have been tested and most of them have caused strong hydrogen production when magnesium alloys and graphite are conditioned together because of galvanic corrosion. Exceptions are binders based on alkali hydroxide activated ground granulated blast furnace slag (BFS) which are presented in this article.

  17. Influence De La Gestation Sur Les Taux De Calcium, Sodium ...

    African Journals Online (AJOL)

    calcium (Ca), sodium (Na), potassium (K) and magnesium (Mg). The quantity of minerals in the serum of individual sow was determined by atomic absorption spectrophotometer. The level of studied minerals was relatively higher in gravid sows as compared to non gravid. However, the difference was significant only for the ...

  18. The characterisation of organic components in the calcium and ...

    African Journals Online (AJOL)

    Sappi Saiccor is one of the few pulp mills that use the acid sulphite pulping process with hardwood feedstock to produce a high-grade cellulose pulp. The major constituents identified in the calcium effluent stream and the magnesium condensate effluent stream were a mixture of lignan isomers, episyringaresinol and ...

  19. Drug-loaded Cellulose Acetate and Cellulose Acetate Butyrate Films ...

    African Journals Online (AJOL)

    The purpose of this research work was to evaluate the contribution of formulation variables on release properties of matrix type ocular films containing chloramphenicol as a model drug. This study investigated the use of cellulose acetate and cellulose acetate butyrate as film-forming agents in development of ocular films.

  20. Biochemistry of the normal dura mater of the human brain determination of water, sodium, potassium, calcium, phosphorus, magnesium, copper, iron, sulfur and nitrogen contents Estudo bioquímico da dura mater normal do cérebro humano: conteúdo de água, sódio, potássio, cálcio, fósforo, magnésio, cobre ferro, enxôfre e nitrogênio

    Directory of Open Access Journals (Sweden)

    Horacio M. Canelas

    1969-06-01

    Full Text Available The concentrations of water, sodium, potassium, calcium, phosphorus, magnesium, copper, iron, sulfur, and nitrogen were determined in samples of apparently normal dura mater removed from 18 subjects recently dead by craniocerebral trauma. The average concentrations expressed in dry weight were: water 79.55 g/100 g ± 2.52; sodium 1.63 mequiv/100 g ±0.27; potassium 3.68 mequiv/100 g ± 0.66; calcium 119.84 mg/100 g ± 107.40; phosphorus 68.2 mg/100 g ± 34.5; magnesium 0.61 mequiv/100 g ± 0.37; copper 249.8 /xg/100 g ± 109.4; iron 0.82 mg/100 g ± 0.28; sulfur 490.7 mg/100 g ± 22.5; nitrogen 3.33 g/100 g ± 0.17.Foram determinadas as concentrações de água, sódio, potássio, cálcio, fósforo, magnésio, cobre, ferro, enxôfre e nitrogênio de espécimes de dura máter aparentemente normal retirados de 18 indivíduos recentemente falecidos em conseqüência de traumatismo crânio-encefálico. As concentrações médias, expressas em peso seco, foram as seguintes: água 79,55 g/100 g ± 2,52; sódio 1,63 mequiv/100 g ± 0,27; potássio 3,68 mequiv/100 g ± 0,66; cálcio 119,84 mg/100 g ± 107,40; fósforo 68,2 mg/100 g ± 34,5; magnésio 0,61 mequiv/100 g ± 0,37; cobre 249,8 mg/100 ± 109,4; ferro 0,82 mg/100 g ± 0,28; enxôfre 490,7 mg/100 g ± 22,5; nitrogênio 3,33 g/100 g ± 0,17.

  1. Magnesium Repair by Cold Spray

    National Research Council Canada - National Science Library

    Champagne, V. K; Leyman, P.F; Helfritch, D. J

    2008-01-01

    .... Army Research Laboratory has developed a cold spray process to reclaim magnesium components that shows significant improvement over existing methods and is in the process of qualification for use on rotorcraft...

  2. Effects of Calcium chloride and magnesium sulphate treatments on ...

    African Journals Online (AJOL)

    ... mg/l solutions of CaCl2 and MgSO4 to investigate the effects of the divalent cations Ca2+ and Mg2+ on visually assessed ripening, the quality of pigments, the total lipids content and the water content. Treatments with both salts in the concentration range used retarded the ripening process in bananas and in pineapples.

  3. A study of serum magnesium, calcium and phosphorus level, and ...

    African Journals Online (AJOL)

    M.P. Basheer

    2015-11-30

    Nov 30, 2015 ... that there is cognitive impairment in uneducated and elderly participants. The verbal fluency test in male and female was also compared. The score in male and female was 21.48. ± 3.52 and 20.5 ± 3.661 respectively. Statistically significant difference was observed between the scores of males and females ...

  4. Calcium, Magnesium, Iron, Zinc and Copper, Compositions of ...

    African Journals Online (AJOL)

    Backround: As breast milk is normally the only source of food in the early stages of life, the dietary levels of the essential elements in the milk of lactating mothers are significantly important. Ethiopia is a country of many nations and nationalities with distinct dietary habits. This variation in food habit may result in the variation ...

  5. Spectrophotometric Titration of a Mixture of Calcium and Magnesium.

    Science.gov (United States)

    Fulton, Robert; And Others

    1986-01-01

    Describes a spectrophotometric titration experiment which uses a manual titration spectrophotometer and manually operated buret, rather than special instrumentation. Identifies the equipment, materials, and procedures needed for the completion of the experiment. Recommends the use of this experiment in introductory quantitative analysis…

  6. Mechanism of magnesium activation of calcium-activated potassium channels.

    Science.gov (United States)

    Shi, Jingyi; Krishnamoorthy, Gayathri; Yang, Yanwu; Hu, Lei; Chaturvedi, Neha; Harilal, Dina; Qin, Jun; Cui, Jianmin

    2002-08-22

    Large-conductance (BK type) Ca(2+)-dependent K(+) channels are essential for modulating muscle contraction and neuronal activities such as synaptic transmission and hearing. BK channels are activated by membrane depolarization and intracellular Ca(2+) and Mg(2+) (refs 6-10). The energy provided by voltage, Ca(2+) and Mg(2+) binding are additive in activating the channel, suggesting that these signals open the activation gate through independent pathways. Here we report a molecular investigation of a Mg(2+)-dependent activation mechanism. Using a combined site-directed mutagenesis and structural analysis, we demonstrate that a structurally new Mg(2+)-binding site in the RCK/Rossman fold domain -- an intracellular structural motif that immediately follows the activation gate S6 helix -- is responsible for Mg(2+)-dependent activation. Mutations that impair or abolish Mg(2+) sensitivity do not affect Ca(2+) sensitivity, and vice versa. These results indicate distinct structural pathways for Mg(2+)- and Ca(2+)-dependent activation and suggest a possible mechanism for the coupling between Mg(2+) binding and channel opening.

  7. In vitro antioxidant properties of calcium dobesilate.

    Science.gov (United States)

    Brunet, J; Farine, J C; Garay, R P; Hannaert, P

    1998-01-01

    Calcium dobesilate, a vascular protective agent, was tested in vitro for its scavenging action against oxygen free radicals. Calcium dobesilate was as potent as rutin to scavenge hydroxyl radicals (IC50 = 1.1 vs 0.7 microM, respectively). It was also able to scavenge superoxide radicals, but with 23 times less potency than rutin (IC50 = 682 vs 30 microM, respectively). Calcium dobesilate significantly reduced platelet activating factor (PAF)-induced chemiluminescence in human PMN cells and lipid peroxidation by oxygen free radicals in human erythrocyte membranes, although these actions required calcium dobesilate concentrations > or = 50 microM. Finally, in cultured bovine aortic endothelial cells, magnesium dobesilate reduced the increase in cytosolic free calcium induced by hydrogen peroxide and inhibited phenazine methosulfate-induced cell potassium loss. In conclusion, calcium dobesilate was effective in scavenging hydroxyl radicals in vitro, at therapeutically relevant concentrations. Conversely, higher concentrations of the compound were required to scavenge superoxide radicals or to protect the cells against the deleterious effects of intracellular reactive oxygen species. Further studies in vivo are required to determine if these antioxidant properties of calcium dobesilate can play a role in its vascular protective mechanisms.

  8. Magnesium salts as compounds of the preparation of magnesium oxide from Tunisian natural brines

    OpenAIRE

    Behij Souheil; Hammi Halim; Hamzaoui Hichem Ahmed; M’nif Adel

    2013-01-01

    Magnesium oxide is one of the most important magnesium compounds used in industry. The production of MgO is often done from calcined magnesium carbonate or from natural magnesium saline solutions (sea water and brines). In the case of these solutions, magnesium oxide is precipitated after the addition of a strong base (eg. Ammonia). Magnesium hydroxide is calcined after its separation from the excess resulting from the strong base through filtration. Thus, magnesia qualities may differ ...

  9. Ultralight Magnesium-Lithium Alloys

    OpenAIRE

    A. Białobrzeski; K. Saja; Hubner, K.

    2007-01-01

    The article gives basic information on the chief constituents of Mg-Li alloys and on their expected properties. A schematic representation and technical performance of a pilot stand for melting and pouring of reactive ultralight magnesium-based alloys have been presented. The preliminary data regarding the manufactured magnesium alloys with about 2-3 % Li and about 10 % Li have been given in the form of microstructures and chemical compositions.

  10. Development of magnesium diecasting alloys

    Energy Technology Data Exchange (ETDEWEB)

    King, J.F. (Magnesium Elektron, Manchester (United Kingdom))

    1998-01-01

    Although there are many fascinating aspects of the development of magnesium diecasting alloys, the volume potential of the automotive industry has always had a major influence on justifying the significant R and D expenditure necessary for this task. Apart from a review of the history of magnesium diecasting alloy development, I would therefore like to focus this presentation on aspects of development specifically relevant to current automotive requirements. (orig.)

  11. [Adjuvants in modern anesthesia - magnesium].

    Science.gov (United States)

    Picardi, Susanne; Lirk, Philipp; Blobner, Manfred; Schönherr, Marianne E; Hollmann, Markus W

    2015-06-01

    Magnesium plays a key role in many cellular functions and there is growing interest in its role in perioperative medicine. While experimental studies provided promising results for several disease states, clinical trials mainly gave conflicting results. This review article summarizes current knowledge on the homeostasis of magnesium as well as on its proposed indications and recommendations in the clinical setting. © Georg Thieme Verlag Stuttgart · New York.

  12. In-house development of an optimized synthetic module for routine [11C]acetate production

    OpenAIRE

    Jang, Hwa Youn; Kwon, Seong Young; Pyo, Ayoung; Hur, Min Goo; Kim, Sang Wook; Park, Jeong-Hoon; Kim, Hee-jung; Yang, Seung Dae; Lee, Sunwoo; Kim, Dong-Yeon; Min, Jung-Joon

    2014-01-01

    [11C]Acetate, a radiotracer for PET imaging, is a promising radiopharmaceutical for overcoming the limitation of 2-deoxy-2-[18F]fluoro-d-glucose in a number of cancers. Here, the optimized automatic synthesis of [11C]acetate using an in-house-developed module under different conditions has been reported for routine production. [11C]CO2 was produced in a 16.4 MeV PETtrace cyclotron, and methyl magnesium chloride was used for synthesis. For product purification, ion-exchange solid-phase extract...

  13. Acetate metabolism in Methanothrix soehngenii

    NARCIS (Netherlands)

    Jetten, M.S.M.

    1991-01-01

    Acetate is quantitatively the most important intermediate in the anaerobic degradation of soluble organic matter. The conversion rate of acetate by methanogenic bacteria is proposed to be the rate limiting step in this degradation The study of acetoclastic methanogens, therefore is of

  14. (VI) oxide in acetic acid

    African Journals Online (AJOL)

    The oxidation of cyclohexene by chromium (VI) oxide in aqueous and acetic media was studied. The reaction products were analysed using infra red (IR) and gas chromatography coupled with mass (GC/MS) spectroscopy. The major products of the oxidation reaction in acetic acid medium were cyclohexanol, ...

  15. EFFECT OF MAGNESIUM AS SUBSTITUTE MATERIAL IN ENZYME MEDIATED CALCITE PRECIPITATION (EMCP FOR SOIL IMPROVEMENT TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Heriansyah ePutra

    2016-05-01

    Full Text Available The optimization of enzyme-mediated calcite precipitation (EMCP was evaluated as a soil improvement technique. In our previous works, purified urease was utilized to bio-catalyze the hydrolysis of urea, which causes the supplied Ca2+ to precipitate with CO32- as calcium carbonate. In the present work, magnesium chloride was newly added to the injecting solutions to delay the reaction rate and to enhance the amount of carbonate precipitation. Soil specimens were prepared in PVC cylinders and treated with concentration-controlled solutions composed of urea, urease, calcium, and magnesium chloride. The mechanical properties of the treated soil specimens were examined through unconfined compressive strength (UCS tests. A precipitation ratio of the carbonate up to 90% of the maximum theoretical precipitation was achieved by adding a small amount of magnesium chloride. Adding magnesium chloride as a delaying agent was indeed found to reduce the reaction rate of the precipitation, which may increase the volume of the treated soil if used in real fields because of the slower precipitation rate and the resulting higher injectivity. A mineralogical analysis revealed that magnesium chloride decreases the crystal size of the precipitated materials and that another carbonate of aragonite is newly formed. Mechanical test results indicated that carbonate precipitates within the soils and brings about a significant improvement in strength. A maximum UCS of 0.6 MPa was obtained from the treated samples.

  16. Serum Magnesium and Vitamin D Levels as Indicators of Asthma Severity.

    Science.gov (United States)

    Shaikh, Mohammed Nadeem; Malapati, Brahma Reddy; Gokani, Ruchi; Patel, Bhavita; Chatriwala, Mitul

    2016-01-01

    Background. Serum magnesium levels affect the concentration of circulating vitamin D in blood and subsequently it affects the immunity; thus it plays significant role in the pathogenesis of asthma. Asthma, in adults, is less studied and hypomagnesemia along with vitamin D deficiency and insufficiency is common in asthmatic individuals, which causes frequent asthma attacks, respiratory infections, severe exacerbations, and poor response to bronchodilators. Objective. To detect the magnitude of vitamin D insufficiency and deficiency and serum magnesium levels among asthmatic patients and to correlate them with the severity of asthma. Materials and Methods. This is a cross-sectional case-control study which includes 60 patients of chronic stable asthma and 60 healthy controls. After taking clinical history and systemic examination, pulmonary function test was done. Serum levels of magnesium, 25-hydroxycholecalciferol [25(OH)D], and calcium were measured in all the subjects. Results. Significant correlation was found between vitamin D deficiency, hypomagnesemia, and asthma severity. Serum calcium levels were unaffected by that. Conclusion. Vitamin D and serum magnesium deficiency are highly prevalent in patients with asthma. Increased asthma severity, frequency of attacks, and exacerbation are associated with lower levels of one or both. Serum 25(OH)D and magnesium levels may serve as important markers of asthma severity.

  17. Serum Magnesium and Vitamin D Levels as Indicators of Asthma Severity

    Directory of Open Access Journals (Sweden)

    Mohammed Nadeem Shaikh

    2016-01-01

    Full Text Available Background. Serum magnesium levels affect the concentration of circulating vitamin D in blood and subsequently it affects the immunity; thus it plays significant role in the pathogenesis of asthma. Asthma, in adults, is less studied and hypomagnesemia along with vitamin D deficiency and insufficiency is common in asthmatic individuals, which causes frequent asthma attacks, respiratory infections, severe exacerbations, and poor response to bronchodilators. Objective. To detect the magnitude of vitamin D insufficiency and deficiency and serum magnesium levels among asthmatic patients and to correlate them with the severity of asthma. Materials and Methods. This is a cross-sectional case-control study which includes 60 patients of chronic stable asthma and 60 healthy controls. After taking clinical history and systemic examination, pulmonary function test was done. Serum levels of magnesium, 25-hydroxycholecalciferol [25(OHD], and calcium were measured in all the subjects. Results. Significant correlation was found between vitamin D deficiency, hypomagnesemia, and asthma severity. Serum calcium levels were unaffected by that. Conclusion. Vitamin D and serum magnesium deficiency are highly prevalent in patients with asthma. Increased asthma severity, frequency of attacks, and exacerbation are associated with lower levels of one or both. Serum 25(OHD and magnesium levels may serve as important markers of asthma severity.

  18. Page 1 360 J. M. SEHGAL AND T. R. SESHADRI ethyl acetate ...

    Indian Academy of Sciences (India)

    ethyl acetate-petroleum ether mixture when it appeared as yellow soft needles melting at 271–72°; yield, 1.9 g. (Found: C, 62.9; H, 5-1. Cls Has O, requires C, 62-8; H, 4.7%). It gave a red colour with magnesium and hydrochloric acid and a brownish red colour with aqueous ferric chloride and did not emit any fluorescence ...

  19. Get Enough Calcium

    Science.gov (United States)

    ... Calcium Print This Topic En español Get Enough Calcium Browse Sections The Basics Overview Foods and Vitamins ... women, don't get enough calcium. How much calcium do I need every day? Women: If you ...

  20. Calcium carbonate overdose

    Science.gov (United States)

    Tums overdose; Calcium overdose ... Calcium carbonate can be dangerous in large amounts. ... Some products that contain calcium carbonate are certain: ... and mineral supplements Other products may also contain calcium ...

  1. Correcting magnesium deficiencies may prolong life

    Directory of Open Access Journals (Sweden)

    Rowe WJ

    2012-02-01

    Full Text Available William J RoweFormer Assistant Clinical Professor of Medicine, Medical University of Ohio at Toledo, Ohio, USAAbstract: The International Space Station provides an extraordinary facility to study the accelerated aging process in microgravity, which could be triggered by significant reductions in magnesium (Mg ion levels with, in turn, elevations of catecholamines and vicious cycles between the two. With space flight there are significant reductions of serum Mg (P < 0.0001 that have been shown in large studies of astronauts and cosmonauts. The loss of the functional capacity of the cardiovascular system with space flight is over ten times faster than the course of aging on Earth. Mg is an antioxidant and calcium blocker and in space there is oxidative stress, insulin resistance, and inflammatory conditions with evidence in experimental animals of significant endothelial injuries and damage to mitochondria. The aging process is associated with progressive shortening of telomeres, repetitive DNA sequences, and proteins that cap and protect the ends of chromosomes. Telomerase can elongate pre-existing telomeres to maintain length and chromosome stability. Low telomerase triggers increased catecholamines while the sensitivity of telomere synthesis to Mg ions is primarily seen for the longer elongation products. Mg stabilizes DNA and promotes DNA replication and transcription, whereas low Mg might accelerate cellular senescence by reducing DNA stability, protein synthesis, and function of mitochondria. Telomerase, in binding to short DNAs, is Mg dependent. On Earth, in humans, a year might be required to detect changes in telomeres, but in space there is a predictably much shorter duration required for detection, which is therefore more reasonable in time and cost. Before and after a space mission, telomere lengths and telomerase enzyme activity can be determined and compared with age-matched control rats on Earth. The effect of Mg supplementation

  2. Magnesium and fetal growth

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, K.

    1988-01-01

    Fetal growth retardation and premature labor are major problems in perinatal medicine today and account for a great deal of the observed fetal morbidity. While the neonatal death rate has steadily declined over the past decade, there has been a lack of concommitant decrease in these two leading problems. Magnesium (Mg/sup ++/) plays a major role in both of these areas of concern. The fact that it is used as a treatment for premature labor has led investigators to look at low Mg/sup ++/ as a possible cause of this poorly understood phenomenon. The second major cause of small for gestational age infants is intrauterine growth retardation, a condition which may be of either fetal or maternal origin. In either case, Mg/sup ++/ may be implicated since it exerts a strong influence on the underlying pathophysiology of placental failure and maternal hypertension. Both of these conditions are mediated by vascular and platelet hyperactivity as well as by and increase in the ration of thromboxane to prostacyclin. Studies in both the human and animal species are beginning to show how Mg/sup ++/ interacts in these conditions to produce such a damaging fetal outcome. The recent use of Doppler velocimetry of the developing fetus has shown reduced fetal vascular and maternal uterine vascular compliance as early as 14 weeks of gestation in those who would be so affected.

  3. OSTEOPOROSIS IN CALCIUM PYROPHOSPHATE CRYSTAL DEPOSITION DISEASE

    Directory of Open Access Journals (Sweden)

    S A Vladimirov

    2013-01-01

    Full Text Available Objective: to study the incidence of osteoporosis (OP in patients with calcium pyrophosphate crystal deposition disease (CPCDD. Subjects and methods. Eighty patients with CPCDD were examined. Bone mineral density (BMD of the forearm, lumbar spine, and femoral neck was determined by dual-energy X-ray absorptiometry. Laboratory diagnosis involved determination of the blood levels of C-reactive protein, parathyroid hormone, calcium, magnesium, and phosphorus and the daily urinary excretion of calcium and phosphates. Results. The patients with OP were significantly older than those with normal BMD and osteopenia. Forearm bones were the most common isolated location of OP and osteopenia. Injuries in the history, traumatic fractures, and the intake of diuretics were somewhat more common in the patients diagnosed with OP. The incidence of hyperparathyroidism did not differ significantly in the groups.

  4. Composite Coatings Combining PEO Layer and EPD Layer on Magnesium Alloy

    Science.gov (United States)

    Jiang, Yongfeng; Bao, Yefeng; Yang, Ke

    Protective composite coatings were prepared combining plasma electrolytic oxidation (PEO) treatment and cathodic electrophoretic deposition on magnesium alloy AZ91D. The corrosion protection of composite coatings were evaluated using potentiodynamic polarization measurements in 3.5% NaCl solution, copper accelerated acetate salt spray (CASS) test and immersion test in acid solution. The adhesion of composite coatings was evaluated using cross-cut test and pull-off test. It is indicated that the corrosion resistance of magnesium alloy AZ91D with the composite coatings is improved obviously compared to it merely with PEO coating and it is also shown that pitting corrosion of PEO coating on magnesium alloy is decreased with EPD post-treatment. The adhesion of composite coatings could be up to 11.3 N/mm2 in quantitative method due to the interlocking effect of organic layer in pores of PEO layer.

  5. [Magnesium sulphate in the treatment of ischemic-hypoxic neonatal encephalopathy].

    Science.gov (United States)

    Kornacka, M K

    2001-01-01

    Hypoxic-ischaemic encephalopathy (HIE) remains one of the most important neurological complications in full and near full term newborns. During HIE glutamate and other excitatory neurotransmitters are released and progressive energy failure in brain is observed. Toxicity of glutamate plays the main role in brain injury. Glutamate activates the specific receptors that, in turn, mediate an overwhelming influx of calcium into the postsynaptic neuron. The pathological changes are located particularly in hippocampus. Magnesium sulfate has been used safely for years to treat preclampsia. The animal experimental evidence support a neuroprotective role for magnesium in HIE.

  6. Mercury's Exosphere During MESSENGER's Second Flyby: Detection of Magnesium and Distinct Distributions of Neutral Species

    Science.gov (United States)

    McClintock, William E.; Vervack, Ronald J., Jr.; Bradley, E. Todd; Killen, Rosemary M.; Mouawad, Nelly; Sprague, Ann L.; Burger, Matthew H.; Solomon, Sean C.; Izenberg, Noam R.

    2009-01-01

    During MESSENGER's second Mercury flyby, the Mercury Atmospheric and Surface Composition Spectrometer observed emission from Mercury's neutral exosphere. These observations include the first detection of emission from magnesium. Differing spatial distributions for sodium, calcium, and magnesium were revealed by observations beginning in Mercury's tail region, approximately 8 Mercury radii anti-sunward of the planet, continuing past the nightside, and ending near the dawn terminator. Analysis of these observations, supplemented by observations during the first Mercury flyby as well as those by other MESSENGER instruments, suggests that the distinct spatial distributions arise from a combination of differences in source, transfer, and loss processes.

  7. Ulipristal acetate for emergency contraception.

    Science.gov (United States)

    Russo, J A; Creinin, M D

    2010-09-01

    Ulipristal acetate is a progesterone receptor modulator. As an emergency contraceptive, a 30-mg micronized formulation is effective for use up to 120 h from unprotected sexual intercourse. Ulipristal acetate acts as an antagonist of the progesterone receptor at the transcriptional level and a competitive antagonist of glucocorticoid receptor function. In contrast to other contraceptives, it has little effect on sex hormone-binding globulin. Although a single small study demonstrated some potential endometrial effects after ulipristal acetate administration, the clinical relevance of these findings is unclear. The incidence of adverse events in clinical trials for emergency contraception has typically been minimal, with one study showing a higher than expected incidence of nausea upon ulipristal acetate use. Ulipristal acetate, like other emergency contraceptive products, can lengthen the time to the next expected menstruation. Ulipristal acetate may have several advantages over currently approved emergency contraceptives. When compared to levonorgestrel, ulipristal acetate maintains its efficacy for a full 120 h, whereas levonorgestrel formulations have declining efficacy over that time frame. Moreover, although the copper intrauterine device (IUD) is highly effective as an emergency contraceptive, accessibility is an issue since the IUD requires a skilled provider for insertion. Copyright 2010 Prous Science, S.A.U. or its licensors. All rights reserved.

  8. Ultrasound-assisted synthesis of magnesium hydroxide nanoparticles from magnesium.

    Science.gov (United States)

    Baidukova, Olga; Skorb, Ekaterina V

    2016-07-01

    Acoustic cavitation in water provides special kinetic and thermodynamic conditions for chemical synthesis and nanostructuring of solids. Using cavitation phenomenon, we obtained magnesium hydroxide from pure magnesium. This approach allows magnesium hydroxide to be synthesized without the requirement of any additives and non-aqueous solvents. Variation of sonochemical parameters enabled a total transformation of the metal to nanosized brucite with distinct morphology. Special attention is given to the obtaining of platelet-shaped, nanometric and de-agglomerated powders. The products of the synthesis were characterized by transmission electron microscopy (TEM), electron diffraction (ED), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Catalytic Combustion of Ethyl Acetate

    OpenAIRE

    ÖZÇELİK, Tuğba GÜRMEN; ATALAY, Süheyda; ALPAY, Erden

    2014-01-01

    The catalytic combustion of ethyl acetate over prepared metal oxide catalysts was investigated. CeO, Co2O3, Mn2O3, Cr2O3, and CeO-Co2O3 catalysts were prepared on monolith supports and they were tested. Before conducting the catalyst experiments, we searched for the homogeneous gas phase combustion reaction of ethyl acetate. According to the homogeneous phase experimental results, 45% of ethyl acetate was converted at the maximum reactor temperature tested (350 °C). All the prepare...

  10. Calcium:magnesium ratio in amendments of soil acidity: nutrition and initial development of corn plants in a Humic Alic Cambisol / Relação cálcio:magnésio do corretivo da acidez do solo na nutrição e no desenvolvimento inicial de plantas de milho em um Cambissolo Húmico Álico

    Directory of Open Access Journals (Sweden)

    Luciano Colpo Gatiboni

    2008-07-01

    Full Text Available The variation in the Ca:Mg ratio in amendments used to neutralize soil acidity is one way of altering the availability of those nutrients to the plants in acid soils. The objective of the work was to evaluate the effect of different proportions of calcium and magnesium in the form of CaCO3 and MgCO3 on the nutrient uptake, and initial production of dry matter by corn plants. The study was carried out in greenhouse conditions, in Lages, SC, with a completely randomized experimental design, with three replications. The treatments were the application of equivalent to 21.0 t ha-1 of lime, using mixtures of CaCO3 and MgCO3 in several proportions to obtain different Ca:Mg ratios (1:1, 2:1, 4:1, 8:1, 16:1 and 32:1, on a Humic Alic Cambisol, with 310 g kg-1 of clay. The application of treatments caused the following Ca:Mg ratios in the CEC: 1.1:1, 2.1:1, 4.0:1, 8.1:1, 16.4:1 and 31.8:1. The high concentrations of exchangeable Ca in soil caused by addition of lime with high Ca content inhibited the uptake of Mg and K by the corn plants. The increase in the soil Ca:Mg ratio reduced the dry matter production and height of plants in the initial stage of developmentA variação na relação Ca:Mg em corretivos da acidez do solo é uma das principais formas de alterar a disponibilidade desses nutrientes às plantas em solos ácidos. O objetivo do trabalho foi avaliar o efeito de diferentes proporções entre cálcio e magnésio na forma de CaCO3 e MgCO3 sobre a absorção de nutrientes e produção inicial de matéria seca de plantas de milho. O estudo o foi desenvolvido em casa de vegetação, em Lages-SC, com delineamento experimental inteiramente casualizado e três repetições. Os tratamentos consistiram na aplicação de dose equivalente a 21,0 t ha-1 de calcário, usando misturas de CaCO3 e MgCO3 em diversas proporções até atingir relações Ca:Mg de 1:1, 2:1, 4:1, 8:1, 16:1 e 32:1, aplicadas num Cambissolo Húmico Álico, com 310 g kg-1 de argila

  11. Effect of oxygen on the hydrogenation properties of magnesium films

    DEFF Research Database (Denmark)

    Ostenfeld, Christopher Worsøe; Chorkendorff, Ib

    2006-01-01

    The effect of magnesium oxide on the magnesium and hydrogen desorption properties of magnesium films have been investigated. We find that by capping metallic magnesium films with oxide overlayers the apparent desorption energy of magnesium is increased from 146 kJ/mol to 314 kJ/mol. The results...... are discussed in light of previous investigations of ball-milled magnesium powders....

  12. Alkoxide-based magnesium electrolyte compositions for magnesium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Sheng; Sun, Xiao-Guang; Liao, Chen; Guo, Bingkun

    2018-01-30

    Alkoxide magnesium halide compounds having the formula: RO--Mg--X (1) wherein R is a saturated or unsaturated hydrocarbon group that is unsubstituted, or alternatively, substituted with one or more heteroatom linkers and/or one or more heteroatom-containing groups comprising at least one heteroatom selected from fluorine, nitrogen, oxygen, sulfur, and silicon; and X is a halide atom. Also described are electrolyte compositions containing a compound of Formula (1) in a suitable polar aprotic or ionic solvent, as well as magnesium batteries in which such electrolytes are incorporated.

  13. Proton pump inhibitor use for 12 months is not associated with changes in serum magnesium levels: a prospective open label comparative study.

    Science.gov (United States)

    Bahtiri, Elton; Islami, Hilmi; Hoxha, Rexhep; Gashi, Afrim; Thaçi, Kujtim; Karakulak, Çağla; Thaçi, Shpetim; Qorraj Bytyqi, Hasime

    2017-03-01

    Proton pump inhibitors (PPIs) are a widely used class of drugs because of a generally acceptable safety profile. Among recently raised safety issues of the long-term use of PPIs is the increased risk of developing hypomagnesemia. As there have been very few prospective studies measuring serum magnesium levels before and after PPI therapy, we aimed to prospectively assess the potential association between PPI therapy for 12 months and the risk of hypomagnesemia as well as the incidence of new-onset hypomagnesemia during the study. In addition, the association of PPI therapy with the risk of hypocalcemia was assessed. The study included 250 patients with normal serum magnesium and total calcium levels, who underwent a long-term PPI treatment. Serum magnesium, total calcium, and parathormone (PTH) levels were measured at baseline and after 12 months. Of the 250 study participants, 209 completed 12 months of treatment and were included in the statistical analysis. The Wilcoxon signed rank test showed no statistically significant differences in serum magnesium levels between measurements at two different time points. However, there were statistically significant differences in serum total calcium and PTH levels in PPI users. Stable serum magnesium levels were demonstrated after 12 months and no association between PPI use and risk of hypomagnesemia was shown in the general population. Significant reductions of serum total calcium levels were demonstrated among PPI users; nevertheless, further research is required before recommending any serum calcium and PTH level monitoring in patients initiated on long-term PPI therapy.

  14. System and process for production of magnesium metal and magnesium hydride from magnesium-containing salts and brines

    Science.gov (United States)

    McGrail, Peter B.; Nune, Satish K.; Motkuri, Radha K.; Glezakou, Vassiliki-Alexandra; Koech, Phillip K.; Adint, Tyler T.; Fifield, Leonard S.; Fernandez, Carlos A.; Liu, Jian

    2016-11-22

    A system and process are disclosed for production of consolidated magnesium metal products and alloys with selected densities from magnesium-containing salts and feedstocks. The system and process employ a dialkyl magnesium compound that decomposes to produce the Mg metal product. Energy requirements and production costs are lower than for conventional processing.

  15. Magnesium sulphate for fetal neuroprotection

    DEFF Research Database (Denmark)

    Bickford, Celeste D; Magee, Laura A; Mitton, Craig

    2013-01-01

    BACKGROUND: The aim of this study was to assess the cost-effectiveness of administering magnesium sulphate to patients in whom preterm birth at ... sensitivity analyses were used to compare the administration of magnesium sulphate with the alternative of no treatment. Two separate cost perspectives were utilized in this series of analyses: a health system and a societal perspective. In addition, two separate measures of effectiveness were utilized: cases...... of cerebral palsy (CP) averted and quality-adjusted life years (QALYs). RESULTS: From a health system and a societal perspective, respectively, a savings of $2,242 and $112,602 is obtained for each QALY gained and a savings of $30,942 and $1,554,198 is obtained for each case of CP averted when magnesium...

  16. Calcium paradox and calcium entry blockers

    NARCIS (Netherlands)

    Ruigrok, T.J.C.; Slade, A.M.; Nayler, W.G.; Meijler, F.L.

    1984-01-01

    Reperfusion of isolated hearts with calcium-containing solution after a short period of calcium-free perfusion results in irreversible cell damage (calcium paradox). This phenomenon is characterized by an excessive influx of calcium into the cells, the rapid onset of myocardial contracture,

  17. Antibiofilm Properties of Acetic Acid

    Science.gov (United States)

    Bjarnsholt, Thomas; Alhede, Morten; Jensen, Peter Østrup; Nielsen, Anne K.; Johansen, Helle Krogh; Homøe, Preben; Høiby, Niels; Givskov, Michael; Kirketerp-Møller, Klaus

    2015-01-01

    Bacterial biofilms are known to be extremely tolerant toward antibiotics and other antimicrobial agents. These biofilms cause the persistence of chronic infections. Since antibiotics rarely resolve these infections, the only effective treatment of chronic infections is surgical removal of the infected implant, tissue, or organ and thereby the biofilm. Acetic acid is known for its antimicrobial effect on bacteria in general, but has never been thoroughly tested for its efficacy against bacterial biofilms. In this article, we describe complete eradication of both Gram-positive and Gram-negative biofilms using acetic acid both as a liquid and as a dry salt. In addition, we present our clinical experience of acetic acid treatment of chronic wounds. In conclusion, we here present the first comprehensive in vitro and in vivo testing of acetic acid against bacterial biofilms. PMID:26155378

  18. Microstructural and technological optimisation of magnesium alloys

    OpenAIRE

    Facchinelli, Nicola

    2013-01-01

    Magnesium is one of the most abundance element in nature, and it's characterised by a lower density than aluminium. These characteristics confer great potential to magnesium alloys, which are so used for specialised applications, like for military purposes and in the aerospace industry. While some magnesium alloys, including the AM60B alloy, are historically associated to high pressure die casting, for such applications the magnesium alloy components are usually produced by the gravity castin...

  19. Magnesium removal in the electrolytic zinc industry

    OpenAIRE

    Booster, J.L.

    2003-01-01

    Electrolytic zinc plants need to take measures to control the magnesium content in their process liquors, because the natural magnesium bleed does not balance the input from concentrates. Presently used methods are environmentally unfriendly (due to the production of large amounts of waste gypsum) or expensive. Therefore, an alternative process route is explored in which magnesium is removed from zinc electrolyte by selective precipitation of magnesium fluoride (sellaite). As standard applica...

  20. The effect of foliar nutrition of spinach (Spinacia oleracea L. with magnesium salts and urea on gas exchange, leaf yield and quality

    Directory of Open Access Journals (Sweden)

    Edward Borowski

    2012-12-01

    Full Text Available In a pot experiment conducted in a phytotron, the effectiveness of foliar nutrition of spinach (Spinacia oleracea L. with different magnesium salts with and without the addition of 0.5% CO(NH22 was studied. Magnesium was applied 3 times in the form of solutions of MgSO4 x 7H2O, Mg(NO32 x 6H2O, MgCl2 x 6H2O, C4H6O4Mg x 4H2O, compared to water as the control treatment. The obtained results showed that foliar feeding of spinach with inorganic magnesium salts was an efficient method for supplementing the Mg level in plants during the growing period. But the application of a metalo-organic complex in the form of magnesium acetate (C4H6O4Mg x 4H2O at a concentration of 1.7%, in spite of a similar effect on leaf Mg content, induced phytotoxic symptoms in the form of chlorotic and necrotic spots on the leaves. The application of the solutions of inorganic magnesium salts had a significant effect, resulting in more intensive leaf gas exchange (stomatal conductance, transpiration and photosynthesis and an increase in leaf yield. Magnesium sulphate affected the abovementioned processes in the most effective way, while magnesium acetate had a negative impact. Foliar feeding of spinach with the magnesium salts resulted in an increased leaf content of protein, chlorophyll, carotenoids, nitrates and proline, but a decrease in vitamin C content. The addition of urea to the applied magnesium salt solutions increased the plant gas exchange rates and the leaf content of protein, chlorophyll, carotenoids, nitrates and proline, but it decreased the content of vitamin C, potassium and magnesium.

  1. Magnesium alloying - some metallurgical aspects

    Energy Technology Data Exchange (ETDEWEB)

    Pekgueleryuez, M.Oe. [Inst. of Magnesium Technology (ITM), Quebec, PQ (Canada); Avedesian, M.M. [Inst. of Magnesium Technology (ITM), Quebec, PQ (Canada)

    1992-12-31

    The incentive for alloy development is the need for new materials with a combination of better performance properties at lower cost. Over the past 45 years the development of new Mg alloys has lagged steel, aluminum, copper, zinc and other metals. The reasons for the slow development of Mg alloys since the 1920`s may have been the real and perceived short comings of Mg which has limited the wide acceptance of the metal by the various industries. In addition the advent of high performance plastics has put new competitive pressure on magnesium. Upon a close look, it can be seen that Mg does not possess a full alloy spectrum; there are really three to four major commercial alloy systems such as Mg-Al-Zn, Mg-Al, Mg-Zn and Mg-Rare Earths. In 1990 most magnesium usage for structural applications was in diecasting (36 kt) and 90% of this was in one alloy, AZ91D. This shows that Mg has not yet fully realized its potential as a structural metal. The 1990`s may, however, generate a long term driving force for magnesium alloy development due to the fact that industries such as the transport industry are faced more than ever with weight reduction objectives. They are driven to use light weight metals and will continue to do so in the future. Magnesium which is the lightest structural metal offers an attractive solution and the interest in the metal is increasing rapidly. This paper attempts to address the major problems of magnesium alloys with the view of identifying opportunities for cost-competitive ways of eliminating the problems of magnesium via alloy and microstructural design. A basic understanding of the fundamental mechanisms affecting strength and creep of Mg is also presented. (orig.)

  2. Magnesium and related low alloys

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, J.; Caillat, R.; Darras, R. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    In the first part the authors examine the comparative corrosion of commercial magnesium, of a magnesium-zirconium alloy (0,4 per cent {<=} Zr {<=} 0,7 per cent) of a ternary magnesium-zinc-zirconium alloy (0,8 per cent {<=} Zn {<=} 1,2 per cent) and of english 'Magnox type' alloys, in dry carbon dioxide-free air, in damp carbon dioxide-free air, and in dry and damp carbon dioxide, at temperatures from 300 to 600 deg. C. In the second part the structural stability of these materials is studied after annealings, of 10 to 1000 hours at 300 to 450 deg. C. Variations in grain after these heat treatments and mechanical stretching properties at room temperature are presented. Finally various creep rate and life time diagrams are given for these materials, for temperatures ranging from 300 to 450 deg. C. (author) [French] Dans une premiere partie les auteurs etudient la corrosion comparee du magnesium commercial, d'un alliage magnesium-zirconium (0,4 pour cent {<=} Zr {<=} 0,7 pour cent), d'un alliage ternaire magnesium-zinc-zirconium (0,8 pour cent {<=} Zn {<=} 1,2 pour cent), et d'alliages anglais 'type Magnox', dans l'air sec decarbonate, l'air humide decarbonate, le gaz carbonique sec et humide a des temperatures de 300 a 600 deg. C. Dans une seconde partie, est etudiee la stabilite structurale de ces materiaux apres des recuits de 300 a 450 deg. C, et de 10 a 1000 heures. Sont presentees les variations, apres ces traitements thermiques, de la grosseur du grain, et des caracteristiques mecaniques de traction a la temperature ambiante. Enfin, quelques diagrammes de vitesse de fluage et de durees de vie sont presentes sur ces materiaux pour des temperatures variant entre 300 et 450 deg. C. (auteur)

  3. Magnesium enhances adherence and cartilage formation of synovial mesenchymal stem cells through integrins.

    Science.gov (United States)

    Shimaya, M; Muneta, T; Ichinose, S; Tsuji, K; Sekiya, I

    2010-10-01

    We previously reported that more than 60% of synovial mesenchymal stem cells (MSCs) placed on osteochondral defects adhered to the defect within 10 min and promoted cartilage regeneration. The efficiency of adherence is considered to depend on the interaction between cells and extracellular matrix (ECM), in which integrins may play some important roles. Divalent cations such as calcium, magnesium, and manganese may affect functions of integrins, and the integrins may be involved in differentiation of MSCs. Among divalent cations, magnesium is used in clinical practice as a therapeutic agent and increases the affinity of integrin to ECM. In this study, we investigated whether magnesium enhanced adherence and chondrogenesis of synovial MSC through integrins. We performed assays for adherence of human synovial MSCs to collagen-coated slides, in vitro chondrogenesis, ex vivo assays for adherence of human synovial MSCs to osteochondral defect, and in vivo assays for adherence and cartilage formation of synovial MSCs in a rabbit osteochondral defect model. Magnesium increased adhesion of human synovial MSCs to collagen, and this effect was inhibited by neutralizing antibodies for integrin α3 and β1. Magnesium also promoted synthesis of cartilage matrix during in vitro chondrogenesis of synovial MSCs, which was diminished by neutralizing antibodies for integrin β1 but not for integrin α3. Ex vivo analyses demonstrated that magnesium enhanced adherence of human synovial MSCs to osteochondral defects. In vivo studies in rabbits showed that magnesium promoted adherence at 1 day and cartilage formation of synovial MSCs at 2 weeks. Magnesium enhanced adherence of synovial MSCs through integrins, which promoted synthesis of cartilage matrix at an early phase. Copyright © 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  4. 21 CFR 582.5431 - Magnesium oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Magnesium oxide. 582.5431 Section 582.5431 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5431 Magnesium oxide. (a) Product. Magnesium oxide. (b) Conditions of use. This substance...

  5. 21 CFR 582.1431 - Magnesium oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Magnesium oxide. 582.1431 Section 582.1431 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1431 Magnesium oxide. (a) Product. Magnesium oxide. (b) Conditions of use. This substance is...

  6. Zonder magnesium zouden planten niet groen zijn

    NARCIS (Netherlands)

    Heuvelink, E.; Kierkels, T.

    2007-01-01

    Magnesium is het centrale element in het molecuul van het bladgroen. Bij een gebrek kleuren daarom de bladeren geel tussen de nerven. Zware metalen kunnen de plaats van magnesium in het bladgroen innemen. De plant kan dan niet meer assimileren. Magnesium is verder belangrijk bij heel veel processen

  7. Magnesium supplementation in children with attention deficit ...

    African Journals Online (AJOL)

    ADHD children were further assessed by Wechsler intelligence scale for children, Conners' parent rating scale, and Wisconsin card sorting test. Then magnesium deficient patients were ... minor side effects from magnesium supplementation. Conclusion: Magnesium supplementation in ADHD, proves its value and safety.

  8. 21 CFR 582.1428 - Magnesium hydroxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Magnesium hydroxide. 582.1428 Section 582.1428 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1428 Magnesium hydroxide. (a) Product. Magnesium hydroxide. (b) Conditions of use. This...

  9. Magnesium homeostasis in Mammalian cells.

    Science.gov (United States)

    Romani, Andrea M P

    2013-01-01

    Magnesium, the second most abundant cation within the cell, plays an important role in numerous biological functions. Experimental evidence indicates that mammalian cells tightly regulate cellular magnesium ion content through specific mechanisms controlling Mg(2+) entry and efflux across the cell membrane and the membrane of various cellular organelles as well as intracellular Mg(2+) buffering under resting conditions and following hormonal and metabolic stimuli. This chapter will provide an assessment of the various mechanisms controlling cellular Mg(2+) homeostasis and transport, and the implications changes in cellular Mg(2+) content play under physiological and pathological conditions.

  10. Research Progress in Plasma arc welding of Magnesium Alloys and Magnesium Matrix Composites

    Science.gov (United States)

    Hui, Li; Yang, Zou; Yongbo, Li; Lei, Jiao; Ruijun, Hou

    2017-11-01

    Magnesium alloys and magnesium matrix composites by means of its excellent performance have wide application prospect in electronics, automotive, biotechnology, aerospace field, and welding technology has become a key of restricting its application. This paper describes the welding characteristics of magnesium, the obvious advantages in the application and the domestic and foreign research advance technology of plasma arc welding of magnesium, and summarizes the existing problems and development trends of plasma arc welding technology of magnesium.

  11. Magnesium Diboride Current Leads

    Science.gov (United States)

    Panek, John

    2010-01-01

    A recently discovered superconductor, magnesium diboride (MgB2), can be used to fabricate conducting leads used in cryogenic applications. Dis covered to be superconducting in 2001, MgB2 has the advantage of remaining superconducting at higher temperatures than the previously used material, NbTi. The purpose of these leads is to provide 2 A of electricity to motors located in a 1.3 K environment. The providing environment is a relatively warm 17 K. Requirements for these leads are to survive temperature fluctuations in the 5 K and 11 K heat sinks, and not conduct excessive heat into the 1.3 K environment. Test data showed that each lead in the assembly could conduct 5 A at 4 K, which, when scaled to 17 K, still provided more than the required 2 A. The lead assembly consists of 12 steelclad MgB2 wires, a tensioned Kevlar support, a thermal heat sink interface at 4 K, and base plates. The wires are soldered to heavy copper leads at the 17 K end, and to thin copper-clad NbTi leads at the 1.3 K end. The leads were designed, fabricated, and tested at the Forschungszentrum Karlsruhe - Institut foer Technische Physik before inclusion in Goddard's XRS (X-Ray Spectrometer) instrument onboard the Astro-E2 spacecraft. A key factor is that MgB2 remains superconducting up to 30 K, which means that it does not introduce joule heating as a resistive wire would. Because the required temperature ranges are 1.3-17 K, this provides a large margin of safety. Previous designs lost superconductivity at around 8 K. The disadvantage to MgB2 is that it is a brittle ceramic, and making thin wires from it is challenging. The solution was to encase the leads in thin steel tubes for strength. Previous designs were so brittle as to risk instrument survival. MgB2 leads can be used in any cryogenic application where small currents need to be conducted at below 30 K. Because previous designs would superconduct only at up to 8 K, this new design would be ideal for the 8-30 K range.

  12. Magnesium alloys and graphite wastes encapsulated in cementitious materials: Reduction of galvanic corrosion using alkali hydroxide activated blast furnace slag.

    Science.gov (United States)

    Chartier, D; Muzeau, B; Stefan, L; Sanchez-Canet, J; Monguillon, C

    2017-03-15

    Magnesium alloys and graphite from spent nuclear fuel have been stored together in La Hague plant. The packaging of these wastes is under consideration. These wastes could be mixed in a grout composed of industrially available cement (Portland, calcium aluminate…). Within the alkaline pore solution of these matrixes, magnesium alloys are imperfectly protected by a layer of Brucite resulting in a slow corrosion releasing hydrogen. As the production of this gas must be considered for the storage safety, and the quality of wasteform, it is important to select a cement matrix capable of lowering the corrosion kinetics. Many types of calcium based cements have been tested and most of them have caused strong hydrogen production when magnesium alloys and graphite are conditioned together because of galvanic corrosion. Exceptions are binders based on alkali hydroxide activated ground granulated blast furnace slag (BFS) which are presented in this article. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Magnesium Contamination in Soil at a Magnesite Mining Region of Liaoning Province, China.

    Science.gov (United States)

    Wang, Lei; Tai, Peidong; Jia, Chunyun; Li, Xiaojun; Li, Peijun; Xiong, Xianzhe

    2015-07-01

    Magnesite is the world's most important source material for magnesia refractory production, and Haicheng City in Liaoning Province, China has been called "the magnesium capital of the world." However, magnesite mining in these areas has caused serious environmental problems. Field investigations have shown that the soil profile of many sites in the mining region are contaminated by magnesium, and the magnesium-enriched crusts that have formed on the soil surface have affected ecologically important soil functions, particularly reduced water penetration rate. Laboratory experiment revealed that anionic polyacrylamide and calcium dihydrogen phosphate can be used to improve soil condition, and have positive effects on soil function. The findings of this study are of significance in the magnetite mining areas, providing clear options for the remediation of soils that should be carried out immediately.

  14. Zinc Acetate Immobilized on Mesoporous Materials by Acetate Ionic Liquids as Catalysts for Vinyl Acetate Synthesis

    Directory of Open Access Journals (Sweden)

    Hang Xu

    2015-01-01

    Full Text Available Ionic liquid containing active ingredient Zn(CH3COO2 was loaded in mesoporous silica gel to form supported ionic liquids catalyst (SILC which was used to synthesize vinyl acetate monomer (VAM. SILC was characterized by 1HNMR, FT-IR, TGA, BET, and N2 adsorption/desorption and the acetylene method was used to evaluate SILC catalytic activity and stability in fixed reactor. The result shows that 1-allyl-3-acetic ether imidazole acetate ionic liquid is successfully fixed within mesoporous channel of silica gel. The average thickness of ionic liquid catalyst layer is about 1.05 nm. When the catalytic temperature is 195°C, the acetic acid (HAc conversion is 10.9% with 1.1 g vinyl acetate yield and 98% vinyl acetate (VAc selectivity. The HAc conversion is increased by rise of catalytic temperature and molar ratio of C2H2 : HAc and decreased by mass space velocity (WHSV. The catalyst activity is not significantly reduced within 7 days and VAc selectivity has a slight decrease.

  15. 27 CFR 21.107 - Ethyl acetate.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Ethyl acetate. 21.107....107 Ethyl acetate. (a) 85 percent ester: (1) Acidity (as acetic acid). Not more than 0.015 percent by...); for incorporation by reference, see § 21.6(b).) When 100 ml of ethyl acetate are distilled by this...

  16. 21 CFR 173.228 - Ethyl acetate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethyl acetate. 173.228 Section 173.228 Food and..., Lubricants, Release Agents and Related Substances § 173.228 Ethyl acetate. Ethyl acetate (CAS Reg. No. 141-78... the specifications of the Food Chemicals Codex, 1 (Ethyl Acetate; p. 372, 3d Ed., 1981), which are...

  17. Biomedical applications of magnesium alloys

    NARCIS (Netherlands)

    Sillekens, W.H.; Bormann, D.

    2012-01-01

    This chapter deals with the emerging field of biomedical applications for magnesium-based materials, envisioning degradable implants that dissolve in the human body after having cured a particular medical condition. After outlining the background of this interest, some major aspects concerning

  18. In-house development of an optimized synthetic module for routine [11C]acetate production.

    Science.gov (United States)

    Jang, Hwa Youn; Kwon, Seong Young; Pyo, Ayoung; Hur, Min Goo; Kim, Sang Wook; Park, Jeong-Hoon; Kim, Hee-Jung; Yang, Seung Dae; Lee, Sunwoo; Kim, Dong-Yeon; Min, Jung-Joon

    2015-01-01

    [11C]Acetate, a radiotracer for PET imaging, is a promising radiopharmaceutical for overcoming the limitation of 2-deoxy-2-[18F]fluoro-D-glucose in a number of cancers. Here, the optimized automatic synthesis of [11C]acetate using an in-house-developed module under different conditions has been reported for routine production. [11C]CO2 was produced in a 16.4 MeV PETtrace cyclotron, and methyl magnesium chloride was used for synthesis. For product purification, ion-exchange solid-phase extraction cartridges were used, connected in series. High-performance liquid chromatography and gas chromatography were used to measure radiochemical and chemical purity. The Limulus amebocyte lysate test and the fluid thioglycollate medium test were performed for quality control of [11C]acetate. The total reaction time of [11C]acetate was within 15 min, and the overall decay-corrected radiochemical yield was 84.33±8.85%. Radiochemical purity was greater than 98% when evaluated on an analytical high-performance liquid chromatography system. No endotoxins or anaerobic bacteria were seen on quality control checks. Optimized production of [11C]acetate was achieved by the in-house module. Radiochemical and biological properties of the [11C]acetate produced were appropriate for clinical PET study.

  19. Effect of inorganic anions on the morphology and structure of magnesium calcite.

    Science.gov (United States)

    Kralj, Damir; Kontrec, Jasminka; Brecević, Ljerka; Falini, Giuseppe; Nöthig-Laslo, Vesna

    2004-04-02

    Calcium carbonate was precipitated from calcium hydroxide and carbonic acid solutions at 25 degrees C, with and without addition of different magnesium (MgSO(4), Mg(NO(3))(2) and MgCl(2)) and sodium salts (Na(2)SO(4), NaNO(3) and NaCl) of identical anions, in order to study the mode of incorporation of magnesium and inorganic anions and their effect on the morphology of calcite crystals over a range of initial reactant concentrations and limited c(i)(Mg(2+))/c(i)(Ca(2+)) molar ratios. The morphology, crystal size distribution, composition, structure, and specific surface area of the precipitated crystals, as well as the mode of cation and anion incorporation into the calcite crystal lattice, were studied by a combination of optical and scanning electron microscopy (SEM), electronic counting, a multiple BET method, thermogravimetry, FT-IR spectroscopy, X-ray diffraction (XRD), and electron paramagnetic resonance (EPR) spectroscopy. In the systems of high initial relative supersaturation, precipitation of an amorphous precursor phase preceded the formation of calcite, whereas in those of lower supersaturation calcite was the first and only polymorphic modification of calcium carbonate that appeared in the system. The magnesium content in calcite increased with the magnesium concentration in solution and was correlated with the type of magnesium salt used. Mg incorporation caused the formation of crystals elongated along the calcite c axis and, in some cases, the appearance of new [011] faces. Polycrystalline aggregates were formed when the c(i)(Mg(2+))/c(i)(Ca(2+)) molar ratios in solution were increased. Addition of sulfate ions, alone, caused formation of spherical calcite polycrystalline aggregates.

  20. Strontium- and magnesium-enriched biomimetic β-TCP macrospheres with potential for bone tissue morphogenesis.

    Science.gov (United States)

    Chou, J; Valenzuela, S M; Santos, J; Bishop, D; Milthorpe, B; Green, D W; Otsuka, M; Ben-Nissan, B

    2014-10-01

    During the last two decades, biogenic mineral ions have become important additives in treatments for bone regeneration and repair. Prominent among these is strontium, which is a potent suppressor of osteoclast bone resorption. Another is magnesium, which has a key influence in mineralization processes. The shells of benthic foraminiferans, hydrothermally converted into β-TCP, have been shown to effectively release a number of bone-promoting drugs at clinically relevant levels. In this study we characterized the effects of converted foraminiferan calcium dissolution and the concomitant release profile of intrinsic strontium and magnesium. We tested the effects of strontium- and magnesium-enriched macrospheres on human osteoblast (SaOS-2) and monocytoid (U937) cell lines, which can be induced to express equivalent phagocytic activities to osteoclasts. On dissolution in a biomimetic physiological solution, the macrospheres released biologically significant quantities of calcium and phosphate ions in the first 18 days. At 3 days, during which biogenic mineral ions are released, the number of U937 osteoclast-like monocyte cells decreased, while 4 days later the osteoblast cell number increased. These results show that strontium and magnesium naturally enriched macrospheres are capable of altering the metabolic activities of the cells regulating bone homeostasis. These unique macrospheres are natural origin bone void filler particles that resorb, and release physiologically significant levels of incorporated strontium, magnesium and calcium, which together make a uniquely multifunctional in situ remedy for bone regeneration and repair and the treatment of bone-wasting diseases. Copyright © 2012 John Wiley & Sons, Ltd.