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Sample records for acid phosphates

  1. 21 CFR 182.6085 - Sodium acid phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium acid phosphate. 182.6085 Section 182.6085 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... Sodium acid phosphate. (a) Product. Sodium acid phosphate. (b) Conditions of use. This substance is...

  2. 21 CFR 582.6085 - Sodium acid phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium acid phosphate. 582.6085 Section 582.6085 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Sodium acid phosphate. (a) Product. Sodium acid phosphate. (b) Conditions of use. This substance is...

  3. Proton transport properties of tin phosphate, chromotropic acid ...

    Indian Academy of Sciences (India)

    Tin (IV) phosphates of the class of tetravalent metal acid (TMA) salts have been synthesized by sol–gel method. The functionalized materials of tin (IV) phosphate (SnP) like chromotropic acid anchored tin phosphate (SnPCA) and tin phenyl phosphonate (SnPP) were also synthesized. These materials have been ...

  4. application of ascorbic acid 2-phosphate as a new voltammetric

    African Journals Online (AJOL)

    a

    ) using ascorbic acid 2-phosphate (AAP) as a new voltammetric substrate has been described in this paper. In the alkaline buffer solution the ALP enzymatic hydrolysis product of AAP was ascorbic acid (AA), which was an electro-active ...

  5. APPLICATION OF ASCORBIC ACID 2-PHOSPHATE AS A NEW ...

    African Journals Online (AJOL)

    An electrochemical assay of the enzyme alkaline phosphatase (ALP) using ascorbic acid 2-phosphate (AAP) as a new voltammetric substrate has been described in this paper. In the alkaline buffer solution the ALP enzymatic hydrolysis product of AAP was ascorbic acid (AA), which was an electro-active substance and had ...

  6. Study of Acid Phosphatase in Solubilization of Inorganic Phosphates by Piriformospora indica.

    Science.gov (United States)

    Seshagiri, Swetha; Tallapragada, Padmavathi

    2017-01-02

    Phosphorus is an essential plant macronutrient present in the soil. Only a small portion of phosphorus in soil is taken up by plants and the rest of it becomes unavailable to plants as it is immobilized. Phosphate solubilizing microorganisms play a vital role in converting the insoluble form of phosphates to the soluble form. The present paper reports the solubilization of tricalcium phosphate, rock phosphate, single super phosphate, zinc phosphate and aluminum phosphate by Piriformospora indica with the production of organic acids as well as acid phosphatase. The amount of phosphate released (4.73 mg ml-1) and titratable acidity (0.12%) was found to be the highest in the case of single super phosphate as compared to other phosphate sources. High performance liquid chromatography (HPLC) revealed the presence of oxalic acid, lactic acid, citric acid and succinic acid in the media. Highest phosphatase activity was observed with the cell membrane extract of the organism in the presence of zinc phosphate.

  7. Removal of cadmium from acidic phosphatic solutions

    Energy Technology Data Exchange (ETDEWEB)

    Frankenfeld, K.; Brodt, P.; Eich, G.; Ruschke, P.

    1985-01-08

    The invention is concerned with a process of removing cadmium from acid, especially P/sub 2/O/sub 5/-containing solutions by liquid/liquid extraction with the aid of alkyl amine salts that are dissolved in an inert, organic solvent. The cadmium ions are removed from the acid, aqueous phase and are enriched in the organic phase. The cadmium-containing organic phase, subsequently, is re-extracted with an aqueous salt solution, with the cadmium ions migrating from the organic phase into the aqueous phase. The process is particularly suitable for extracting cadmium from concentrated, highly acid aqueous solutions.

  8. Electrodialysis of Phosphates in Industrial-Grade Phosphoric Acid

    OpenAIRE

    Machorro, J. J.; Olvera, J. C.; Larios, A.; Hernández-Hernández, H. M.; Alcantara-Garduño, M. E.; Orozco, G.

    2013-01-01

    The objective of this research was to study the purification of industrial-grade phosphoric acid (P2O5) by conventional electrodialysis. The experiments were conducted using a three-compartment cell with anion and cation membranes, and industrial acid solution was introduced into the central compartment. The elemental analysis of the diluted solution indicated that the composition of magnesium, phosphates, and sodium was reduced in the central compartment. The ratios of the concentration of t...

  9. Production of citric and oxalic acids and solubilization of calcium phosphate by Penicillium bilaii.

    OpenAIRE

    Cunningham, J. E.; Kuiack, C

    1992-01-01

    An isolate of Penicillium bilaii previously reported to solubilize mineral phosphates and enhance plant uptake of phosphate was studied. Using agar media with calcium phosphate and the pH indicator alizarin red S, the influence of the medium composition on phosphate solubility and medium acidification was recorded. The major acidic metabolites produced by P. bilaii in a sucrose nitrate liquid medium were found to be oxalic acid and citric acid. Citric acid production was promoted under nitrog...

  10. Secretion of Organic Acids by Phosphate Solubilizing Bacteria Isolated from Oxisols

    Directory of Open Access Journals (Sweden)

    Irfan Dwidya Prijambada

    2009-09-01

    Full Text Available Phosphorus availability is a major limiting for crop production. Bacterial solubilization of insoluble inorganic phosphate has been studied as a means of providing available phosphorus for crop production. Bacterial abilities to solubilize calcium phosphate and rock phosphate have been identified to be related with their abilities to produce gluconic acid and ketogluconic acid. However, there is no information regarding the relationship between bacterial ability to solubilize aluminum phosphate and their ability to produce organic acids. This study was conducted to investigate the relationship between bacterial ability to solubilize calcium and aluminum phosphates with their ability to produce organic acids. Bacterial ability to solubilize calcium and aluminum phosphates were determined as the concentration of soluble phosphate in the filtrate of bacterial cultivation media, while bacterial ability to produce organic acids were assessed from the accumulated organic acids in its. The results showed that bacterial abilities to solubilize calcium and aluminum phosphates well related to their abilities to produce organic acids. Organic acids related with the solubilization of calcium phosphate differ from the ones related with the solubilization of aluminum phosphate. Moreover, there is similarity in the production of organic acids related to the solubilization of aluminum phosphates and iron phosphate.

  11. Fact Sheet - Phosphate Fertilizer Production Plants and Phosphoric Acid Manufacturing Plants NESHAP

    Science.gov (United States)

    Fact sheet summarizing National Emission Standards for Hazardous Air Pollutants (NESHAP) for Phosphate Fertilizer Production Plants and Phosphoric Acid Manufacturing Plants (40 CFR 63 Subparts AA and BB).

  12. Synthesis of High Molar Mass Poly(alkylene phosphate)s by Polyaddition of Diepoxides to Difunctional Phosphoric Acids : Unusual Elimination of the Side Reactions

    NARCIS (Netherlands)

    Biedron, T.; Kaluzynski, K.; Pretula, J.; Kubisa, P.; Penczek, S.; Loontjens, T.

    2001-01-01

    The reaction between diepoxides and difunctional acids of phosphorus was studied as a potential route to linear polyesters of phosphoric acid. The reaction between diepoxide and P-OH groups in H3PO4 and related acids leads to linear phosphates, but cyclic phosphates are also formed as side products.

  13. Organic acid production in vitro and plant growth promotion in maize under controlled environment by phosphate-solubilizing fluorescent Pseudomonas

    Directory of Open Access Journals (Sweden)

    Vyas Pratibha

    2009-08-01

    Full Text Available Abstract Background Phosphorus deficiency is a major constraint to crop production due to rapid binding of the applied phosphorus into fixed forms not available to the plants. Microbial solubilization of inorganic phosphates has been attributed mainly to the production of organic acids. Phosphate-solubilizing microorganisms enhance plant growth under conditions of poor phosphorus availability by solubilizing insoluble phosphates in the soil. This paper describes the production of organic acids during inorganic phosphate solubilization and influence on plant growth as a function of phosphate solubilization by fluorescent Pseudomonas. Results Nineteen phosphate-solubilizing fluorescent Pseudomonas strains of P. fluorescens, P. poae, P. trivialis, and Pseudomonas spp. produced gluconic acid, oxalic acid, 2-ketogluconic acid, lactic acid, succinic acid, formic acid, citric acid and malic acid in the culture filtrates during the solubilization of tricalcium phosphate, Mussoorie rock phosphate, Udaipur rock phosphate and North Carolina rock phosphate. The strains differed quantitatively and qualitatively in the production of organic acids during solubilization of phosphate substrates. Cluster analysis based on organic acid profiling revealed inter-species and intra-species variation in organic acids produced by Pseudomonas strains. The phosphate-solubilizing bacterial treatments P. trivialis BIHB 745, P. trivialis BIHB 747, Pseudomonas sp. BIHB 756 and P. poae BIHB 808 resulted in significantly higher or statistically at par growth and total N, P and K content over single super phosphate treatment in maize. These treatments also significantly affected pH, organic matter, and N, P, and K content of the soil. Conclusion The results implied that organic acid production by Pseudomonas strains is independent of their genetic relatedness and each strain has its own ability of producing organic acids during the solubilization of inorganic phosphates

  14. Organic acid production in vitro and plant growth promotion in maize under controlled environment by phosphate-solubilizing fluorescent Pseudomonas.

    Science.gov (United States)

    Vyas, Pratibha; Gulati, Arvind

    2009-08-22

    Phosphorus deficiency is a major constraint to crop production due to rapid binding of the applied phosphorus into fixed forms not available to the plants. Microbial solubilization of inorganic phosphates has been attributed mainly to the production of organic acids. Phosphate-solubilizing microorganisms enhance plant growth under conditions of poor phosphorus availability by solubilizing insoluble phosphates in the soil. This paper describes the production of organic acids during inorganic phosphate solubilization and influence on plant growth as a function of phosphate solubilization by fluorescent Pseudomonas. Nineteen phosphate-solubilizing fluorescent Pseudomonas strains of P. fluorescens, P. poae, P. trivialis, and Pseudomonas spp. produced gluconic acid, oxalic acid, 2-ketogluconic acid, lactic acid, succinic acid, formic acid, citric acid and malic acid in the culture filtrates during the solubilization of tricalcium phosphate, Mussoorie rock phosphate, Udaipur rock phosphate and North Carolina rock phosphate. The strains differed quantitatively and qualitatively in the production of organic acids during solubilization of phosphate substrates. Cluster analysis based on organic acid profiling revealed inter-species and intra-species variation in organic acids produced by Pseudomonas strains. The phosphate-solubilizing bacterial treatments P. trivialis BIHB 745, P. trivialis BIHB 747, Pseudomonas sp. BIHB 756 and P. poae BIHB 808 resulted in significantly higher or statistically at par growth and total N, P and K content over single super phosphate treatment in maize. These treatments also significantly affected pH, organic matter, and N, P, and K content of the soil. The results implied that organic acid production by Pseudomonas strains is independent of their genetic relatedness and each strain has its own ability of producing organic acids during the solubilization of inorganic phosphates. Significant difference in plant growth promotion by efficient

  15. Effects of organic acids of different molecular size on phosphate removal by HZO-201 nanocomposite.

    Science.gov (United States)

    Lin, Bin; Hua, Ming; Zhang, Yanyang; Zhang, Weiming; Lv, Lu; Pan, Bingcai

    2017-01-01

    Various organic acids in wastewater effluent could significantly influence the performance of phosphate adsorbent. This study focused on the effects of organic acids of different-molecular-size on phosphate adsorption by a novel nanocomposite HZO-201. Three organic acids (gallic acid (GA), tannic acid (TA) and humic acid (HA)) with distinct molecular size (HA > TA > GA) were chosen for this purpose. Both isotherm and kinetic tests of phosphate adsorption were conducted in the single-phosphate and binary system, and a series of microscopic techniques (i.e., XPS, FT-IR and SEM-EDX) and N2 adsorption-desorption test were employed to explore the underlying mechanism. It was found that GA could greatly weaken phosphate adsorption capability of HZO-201 by directly competing for ammonium group on the nanocomposite, TA exhibited significant inhibition on phosphate adsorption rate mainly through pore constriction/blockage, while HA posed negligible impact on phosphate adsorption because of the size exclusion effect. It was also observed that although GA, TA and HA showed substantial influence on bulky HZO due to complexation, their impact on the nano-HZO loaded inside HZO-201 was little. The covalently bounded ammonium group and the networking pore structure of HZO-201 may play important roles in it. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. PHOSPHATED, ACID-ETCHED IMPLANTS DECREASE MINERAL APPOSITION RATES NEAR IMPLANTS IN CANINES

    Science.gov (United States)

    Foley, Christine Hyon; Kerns, David G.; Hallmon, William W.; Rivera-Hidalgo, Francisco; Nelson, Carl J.; Spears, Robert; Dechow, Paul C.; Opperman, Lynne A.

    2010-01-01

    Purpose: This study evaluated the effects of phosphate-coated titanium on mineral apposition rate (MAR) and new bone-to-implant contact (BIC) in canines. Materials and Methods: 2.2 mm × 4 mm electrolytically phosphated or non-phosphated titanium implants with acid-etched surfaces were placed in 48 mandibular sites in 6 foxhounds. Tetracycline and calcein dyes were administered 1 week after implant placement and 1 week before sacrifice. At twelve weeks following implant healing, animals were sacrificed. MAR and BIC were evaluated using fluorescence microscopy. Light microscopic and histological evaluation was performed on undecalcified sections. Results: Microscopic evaluation showed the presence of healthy osteoblasts lining bone surfaces near implants. Similar bone-to-implant contact was observed in phosphated and non-phosphated titanium implant sites. MAR was significantly higher near non-phosphated titanium implant surfaces than the phosphated titanium samples. No significant differences were found between dogs or implant sites. Discussion and Conclusion: Acid-etched only implants showed significantly higher mineral apposition rates compared to acid-etched, phosphate-coated implants. PMID:20369085

  17. Effect of humic acid preloading on phosphate adsorption onto zirconium-modified zeolite.

    Science.gov (United States)

    Lin, Jianwei; Zhang, Zhe; Zhan, Yanhui

    2017-05-01

    A zirconium-modified zeolite (ZrMZ) was prepared, and then, humic acid (HA) was immobilized on the ZrMZ surface to prepare HA-loaded ZrMZ (HA-ZrMZ). The obtained ZrMZ and HA-ZrMZ were characterized by energy dispersive X-ray spectroscopy, elemental analyzer, N 2 adsorption/desorption isotherms, pH at the point of zero charge, and X-ray photoelectron spectroscopy. The adsorption characteristics of phosphate on ZrMZ and HA-ZrMZ were comparatively investigated in batch mode. The adsorption mechanism of phosphate on ZrMZ and HA-ZrMZ was investigated by ionic strength effect and 31 P nuclear magnetic resonance. The mechanism for phosphate adsorption onto ZrMZ was the formation of inner-sphere phosphate complexes at the solid/solution interface. The preloading of HA on ZrMZ reduced the phosphate adsorption capacity, and the more the HA loading amount, the lower the phosphate adsorption capacity. However, the preloading of HA on ZrMZ did not change the phosphate adsorption mechanism; i.e., the formation of inner-sphere phosphate surface complexes was still responsible for the adsorption of phosphate on HA-ZrMZ. The decreased phosphate adsorption capacity for ZrMZ after HA coating could be attributed to the fact that the coating of HA on ZrMZ reduced the amount of binding active sites available for phosphate adsorption, changed the adsorbent surface charges, and reduced the specific surface areas and pore volumes of ZrMZ.

  18. Phosphate relationships in acid-sulphate soils of Mbiabet swamp ...

    African Journals Online (AJOL)

    Treatments consisted of potassium dihydrogen phosphate added to the swamp mud, cat-clay, and mud-clay in equal doses of 122 kg/ha P205, fitted into Latin square of 36 x 5 m swamp, except for the control plots. Limestone (CaC03) was applied to both fertilized and unfertilized plots at the rate of 50 kg/ha to reduce

  19. Experimental study on thermal hazard of tributyl phosphate-nitric acid mixtures using micro calorimeter technique

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Qi; Jiang, Lin; Gong, Liang; Sun, Jin-Hua, E-mail: sunjh@ustc.edu.cn

    2016-08-15

    Highlights: • Heat flows after mixing TBP with nitric acid are of different orders of magnitude. • Thermodynamics and kinetics of tributyl phosphate-nitric acid mixtures are derived. • Tributyl phosphate directly reacts with nitric acid and form organic red oil. • Thermal runaway could occur at 79 °C with a high nitric acid concentration. - Abstract: During PUREX spent nuclear fuel reprocessing, mixture of tributyl phosphate (TBP) and hydrocarbon solvent are employed as organic solvent to extract uranium in consideration of radiation contaminated safety and resource recycling, meanwhile nitric acid is utilized to dissolve the spent fuel into small pieces. However, once TBP contacts with nitric acid or nitrates above 130 °C, a heavy “red oil” layer would occur accompanied by thermal runaway reactions, even caused several nuclear safety accident. Considering nitric acid volatility and weak exothermic detection, C80 micro calorimeter technique was used in this study to investigate thermal decomposition of TBP mixed with nitric acid. Results show that the concentration of nitric acid greatly influences thermal hazard of the system by direct reactions. Even with a low heating rate, if the concentration of nitric acid increases due to evaporation of water or improper operations, thermal runaway in the closed system could start at a low temperature.

  20. Effective removal of phosphate from aqueous solution using humic acid coated magnetite nanoparticles.

    Science.gov (United States)

    Rashid, Mamun; Price, Nathaniel T; Gracia Pinilla, Miguel Ángel; O'Shea, Kevin E

    2017-10-15

    Effective removal of excess phosphate from water is critical to counteract eutrophication and restore water quality. In this study, low cost, environmentally friendly humic acid coated magnetite nanoparticles (HA-MNP) were synthesized and applied for the remediation of phosphate from aqueous media. The HA-MNPs, characterized by FTIR, TEM and HAADF-STEM showed the extensive coating of humic acid on the magnetite surface. The magnetic nanoparticles with diameters of 7-12 nm could be easily separated from the reaction mixture by using a simple hand held magnet. Adsorption studies demonstrate the fast and effective separation of phosphate with maximum adsorption capacity of 28.9 mg/g at pH 6.6. The adsorption behavior follows the Freundlich isotherm suggesting the formation of non-uniform multilayers of phosphate on the heterogeneous surface of HA-MNP. The adsorption kinetic fits the pseudo-second order model well with rate constants of 0.206 ± 0.003, 0.073 ± 0.002 and 0.061 ± 0.003 g mg(-1)min(-1) for phosphate (P) concentrations of 2, 5 and 10 mg/L respectively. The removal of phosphate was found higher at acidic and neutral pH compared to basic conditions. The nanoparticles exhibit good selectivity and adsorption efficiency for phosphate in presence of co-existing ions such as Cl(-), SO4(2-)and NO3(-) with some inhibition effect by CO3(2-). The effect of temperature on the adsorption reveals that the process is endothermic and spontaneous. HA-MNPs are promising, simple, environmentally friendly materials for the removal of phosphate from aqueous media. Copyright © 2017. Published by Elsevier Ltd.

  1. Fascinating and challenging role of tungstate promoted vanadium phosphate towards solvent free esterification of oleic acid.

    Science.gov (United States)

    Behera, Gobinda Chandra; Parida, K M

    2012-01-28

    A novel solid acid catalyst has been extensively used for the esterification reaction. Herein, tungstate promoted vanadium phosphate material is fabricated from its precursor, VOHPO(4)·0.5H(2)O and its catalytic activities and structure are investigated in detail. This kind of catalyst is, for the first time, applied for the effective production of biodiesel from fatty acids. Although vanadium phosphate has been extensively used in gas phase oxidation reactions, it has not drawn much attention for its application in liquid phase reactions. Our recent results indicate that vanadium phosphate is an effective, minimally polluting and re-usable catalyst that is highly suited to the production of biodiesel from fatty acids. This work extends the possibility of using VPO in other liquid phase reactions.

  2. Enzymatic Production of Ascorbic Acid-2-phosphate by Recombinant Acid Phosphatase.

    Science.gov (United States)

    Zheng, Kai; Song, Wei; Sun, Anran; Chen, Xiulai; Liu, Jia; Luo, Qiuling; Wu, Jing

    2017-05-24

    In this study, an environmentally friendly and efficient enzymatic method for the synthesis of l-ascorbic acid-2-phosphate (AsA-2P) from l-ascorbic acid (AsA) was developed. The Pseudomonas aeruginosa acid phosphatase (PaAPase) was expressed in Escherichia coli BL21. The optimal temperature, optimal pH, K m , k cat , and catalytic efficiency of recombinant PaAPase were 50 °C, 5.0, 93 mM, 4.2 s -1 , and 2.7 mM -1 min -1 , respectively. The maximal dry cell weight and PaAPase phosphorylating activity reached 8.5 g/L and 1127.7 U/L, respectively. The highest AsA-2P concentration (50.0 g/L) and the maximal conversion (39.2%) were obtained by incubating 75 g/L intact cells with 88 g/L AsA and 160 g/L sodium pyrophosphate under optimal conditions (0.1 mM Ca 2+ , pH 4.0, 30 °C) for 10 h; the average AsA-2P production rate was 5.0 g/L/h, and the AsA-2P production system was successfully scaled up to a 7.5 L fermenter. Therefore, the enzymatic process showed great potential for production of AsA-2P in industry.

  3. Characterization of the plastidic phosphate translocators in the inducible crassulacean acid metabolism plant Mesembryanthemum crystallinum.

    Science.gov (United States)

    Kore-eda, Shin; Nozawa, Akira; Okada, Yusuke; Takashi, Kazuki; Azad, Muhammad Abul Kalam; Ohnishi, Jun-ichi; Nishiyama, Yoshitaka; Tozawa, Yuzuru

    2013-01-01

    In plant Mesembryanthemum crystallinum, which has the inducible crassulacean acid metabolism (CAM), isoforms of plastidic phosphate translocators (pPTs) are categorized into three subfamilies: the triose phosphate/phosphate translocator (McTPT1), the phosphoenolpyruvate/phosphate translocator (McPPT1), and the glucose 6-phosphate/phosphate translocator (McGPT1 and McGPT2). In order to elucidate the physiological roles of these pPTs in M. crystallinum, we determined the substrate specificity of each pPT isoform. The substrate specificities of McTPT1, McPPT1, and McGPT1 showed overall similarities to those of orthologs that have been characterized. In contrast, for glucose 6-phosphate, McGPT2 showed higher selectivity than McGPT1 and other GPT orthologs. Because the expression of McGTP2 is specific to CAM while that of McGTP1 is constitutively expressed in both the C3- and the CAM-state in M. crystallinum, we propose that McGPT2 functions as a CAM system-specific GPT in this plant.

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

    NARCIS (Netherlands)

    Ruhe, P.Q.; Hedberg, E.L.; Padron, N.T.; Spauwen, P.H.M.; Jansen, J.A.; Mikos, A.G.

    2005-01-01

    Injectable calcium phosphate (Ca-P) cement materials exhibit favorable osteocompatible behavior but are resorbed slowly because of a lack of a bone ingrowth-enabling macroporosity. In this study, poly(DL-lactic-co-glycolic acid) (PLGA) microparticles (average size 66 +/- 25 microm) were incorporated

  5. Enhancing phosphate adsorption capacity of SDS-based magnetite by surface modification of citric acid

    Science.gov (United States)

    Yu, Zhigang; Zhang, Chang; Zheng, Zuhong; Hu, Liang; Li, Xuemei; Yang, Zhongzhu; Ma, Chi; Zeng, Guangming

    2017-05-01

    In this study, citric acid (CA) was employed as a low-molecule organic acid to influence the adsorption performance of phosphorus by as-obtained magnetite. The factors including initial phosphate concentrations, dosage of citric acid, pH value, ion strength, contact time and temperature were examined in detail. Results indicated that the dissolution of anion sodium dodecyl sulfate (SDS) covering on surface of magnetite, a slight decrease of Fe level and a superior structure of magnetite after CA modification occurred. The pH-dependence of phosphate adsorption was impeded and the surface potential of magnetite positively increased at pH > 5.0 when CA was added. Non-linear regression Langmuir-Freundlich model was fitted well in thermodynamics, and the opposite adsorption process as a function of temperatures with or without CA addition was due to the decrease of active energy and active mobility of phosphate ion. Finally, the declining adsorption efficiency with increasing cycles was observed while phosphate removal was approximately finished and had small change with 0.05 and 0.1 M of CA addition. Those improvements of removal efficiency of phosphorus by modified iron oxide were because of the removal of anionic SDS that increased the surface positive charge, and especially the dissolution of element Fe into solution to form precipitate with phosphorus ions. The enhanced stability of magnetite by CA also promoted the high removal efficiency of phosphorus. These implications of CA on phosphate removal can be extended to the field where phosphate pollution is notorious but urgent.

  6. Proton transport properties of tin phosphate, chromotropic acid ...

    Indian Academy of Sciences (India)

    Thermal analysis was carried out using Perkin–Elmer thermal analyser. Carbon and hydrogen contents were determined by Coleman analyser model 33. Chemical resistivity in various media (acids, bases and organic solvents) was studied by taking 500 mg of the materials in 50 mL of the particular medium and allowing to.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-06-15

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

  8. Supported phosphate and carbonate salts for heterogeneous catalysis of triglycerides to fatty acid methyl esters

    Science.gov (United States)

    Britton, Stephanie Lynne

    Fatty acid methyl esters made from vegetable oil, or biodiesel, have been identified as a substitute for diesel derived from crude oil. Biodiesel is currently made using a homogeneous base catalyst to perform the transesterification of triglycerides with methanol to generate fatty acid methyl esters (FAME). The use of a homogeneous catalyst necessitates additional purification of the product and byproducts before sale, and the catalyst is consumed and discarded. The development of a heterogeneous basic catalyst for the production of FAME is desirable. Tribasic phosphate salts and dibasic carbonate salts are active for the production of FAME but generally operate as homogeneous catalysts. Supporting these phosphate and carbonate salts on mesoporous MCM-41, microporous silica gel, and nonporous a-alumina proved successful to greater or lesser degrees depending on the identity of the support and pretreatment of the support. Although these salts were supported and were active for the production of FAME from canola oil, they proved to be operating as homogeneous catalysts due to leaching of the active species off the surface of the support. Further investigation of the active species present in the tribasic phosphate catalysts identified the active support as orthophosphate, and NMR studies revealed the phosphorus to be present as orthophosphate and diphosphate in varying proportions in each catalyst. Evaluation of the acid-washing support pretreatment process revealed that the exposure of the support to acid plays a large role in the development of activity on the surface of the catalyst, but manipulation of these parameters did not prevent leaching of the active site off the surface of the catalyst. Alternate methods of support pretreatment were no more effective in preventing leaching. Tribasic phosphate supported on silica gel is not effective as a heterogeneous catalyst for FAME production from triglycerides because of the lack of stability of the phosphate on the

  9. A comparative study of n-hexane isomerization over solid acids catalysts: Sulfated and phosphated zirconia

    Directory of Open Access Journals (Sweden)

    Stojkovic N.

    2012-01-01

    Full Text Available Two series of zirconia based catalysts promoted with either sulfates or phosphates were prepared, calcined at different temperatures (600 and 700°C and evaluated for the n-hexane isomerization reaction. The catalysts with different concentrations of sulfates or phosphates (4 or 10 wt. % were characterized by BET, XRD, SEM methods, and total acidity was evaluated by using the Hammett indicators. Their final catalytic performances were correlated with their physical-chemical properties (surface, structural, textural and morphological. It was found that sulfated zirconia catalyst calcined at lower temperature showed the highest initial activity of all tested catalysts as the result of favorable total acidity, mesopore texture and structural properties. Somewhat lower activity of the sulfated catalyst calcined at higher temperature is related to the content of acid groups partially removed during thermal treatment, thus, lower total acidity, and also to less favorable textural and structural features. Negligible activity of phosphated zirconia catalysts is connected with low total acidity despite the positive status of particular property showing the complexity of the active phase/site formation in the catalyst.

  10. Strigolactone regulates anthocyanin accumulation, acid phosphatases production and plant growth under low phosphate condition in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Shinsaku Ito

    Full Text Available Phosphate is an essential macronutrient in plant growth and development; however, the concentration of inorganic phosphate (Pi in soil is often suboptimal for crop performance. Accordingly, plants have developed physiological strategies to adapt to low Pi availability. Here, we report that typical Pi starvation responses in Arabidopsis are partially dependent on the strigolactone (SL signaling pathway. SL treatment induced root hair elongation, anthocyanin accumulation, activation of acid phosphatase, and reduced plant weight, which are characteristic responses to phosphate starvation. Furthermore, the expression profile of SL-response genes correlated with the expression of genes induced by Pi starvation. These results suggest a potential overlap between SL signaling and Pi starvation signaling pathways in plants.

  11. Phytic acid as alternative setting retarder enhanced biological performance of dicalcium phosphate cement in vitro.

    Science.gov (United States)

    Meininger, Susanne; Blum, Carina; Schamel, Martha; Barralet, Jake E; Ignatius, Anita; Gbureck, Uwe

    2017-04-03

    Dicalcium phosphate cement preparation requires the addition of setting retarders to meet clinical requirements regarding handling time and processability. Previous studies have focused on the influence of different setting modifiers on material properties such as mechanical performance or injectability, while ignoring their influence on biological cement properties as they are used in low concentrations in the cement pastes and the occurrence of most compounds in human tissues. Here, analyses of both material and biological behavior were carried out on samples with common setting retardants (citric acid, sodium pyrophosphate, sulfuric acid) and novel (phytic acid). Cytocompatibility was evaluated by in vitro tests with osteoblastic (hFOB 1.19) and osteoclastic (RAW 264.7) cells. We found cytocompatibility was better for sodium pyrophosphate and phytic acid with a three-fold cell metabolic activity by WST-1 test, whereas samples set with citric acid showed reduced cell number as well as cell activity. The compressive strength (CS) of cements formed with phytic acid (CS = 13 MPa) were nearly equal to those formed with citric acid (CS = 15 MPa) and approximately threefold higher than for other setting retardants. Due to a proven cytocompatibility and high mechanical strength, phytic acid seems to be a candidate replacement setting retardant for dicalcium phosphate cements.

  12. Triphenyl phosphate-induced developmental toxicity in zebrafish: Potential role of the retinoic acid receptor

    Energy Technology Data Exchange (ETDEWEB)

    Isales, Gregory M.; Hipszer, Rachel A.; Raftery, Tara D. [Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, SC (United States); Chen, Albert; Stapleton, Heather M. [Division of Environmental Sciences and Policy, Nicholas School of the Environment, Duke University, Durham, NC (United States); Volz, David C., E-mail: volz@mailbox.sc.edu [Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, SC (United States)

    2015-04-15

    Highlights: • Triphenyl phosphate-induced toxicity in zebrafish embryos is enhanced in the presence of a retinoic acid receptor antagonist. • Triphenyl phosphate uptake or metabolism within zebrafish embryos is not altered in the presence of a retinoic acid receptor antagonist. • Triphenyl phosphate decreases expression of cytochrome P450 26a1 in zebrafish embryos. • Triphenyl phosphate inhibits retinoic acid-induced activation of human retinoic acid receptors. - Abstract: Using zebrafish as a model, we previously reported that developmental exposure to triphenyl phosphate (TPP) – a high-production volume organophosphate-based flame retardant – results in dioxin-like cardiac looping impairments that are independent of the aryl hydrocarbon receptor. Using a pharmacologic approach, the objective of this study was to investigate the potential role of retinoic acid receptor (RAR) – a nuclear receptor that regulates vertebrate heart morphogenesis – in mediating TPP-induced developmental toxicity in zebrafish. We first revealed that static exposure of zebrafish from 5–72 h post-fertilization (hpf) to TPP in the presence of non-toxic concentrations of an RAR antagonist (BMS493) significantly enhanced TPP-induced toxicity (relative to TPP alone), even though identical non-toxic BMS493 concentrations mitigated retinoic acid (RA)-induced toxicity. BMS493-mediated enhancement of TPP toxicity was not a result of differential TPP uptake or metabolism, as internal embryonic doses of TPP and diphenyl phosphate (DPP) – a primary TPP metabolite – were not different in the presence or absence of BMS493. Using real-time PCR, we then quantified the relative change in expression of cytochrome P450 26a1 (cyp26a1) – a major target gene for RA-induced RAR activation in zebrafish – and found that RA and TPP exposure resulted in a ∼5-fold increase and decrease in cyp26a1 expression, respectively, relative to vehicle-exposed embryos. To address whether TPP may

  13. Enhancing phosphate adsorption capacity of SDS-based magnetite by surface modification of citric acid

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Zhigang [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Zhang, Chang, E-mail: zhangchang@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Zheng, Zuhong [College of Life Science and Technology, Hubei Engineering University, Xiaogan 432000, Hubei Province (China); Hu, Liang; Li, Xuemei; Yang, Zhongzhu; Ma, Chi; Zeng, Guangming [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China)

    2017-05-01

    Highlights: • Citric acid (CA) was used to modify the surface structures of SDS-based magnetite. • Dosage of CA, pH values, ion strength, isotherms and dynamics were analyzed. • High CA dissolved anionic SDS and Fe{sup n+} but increased the stability of magnetite. • 0.05 and 0.1 M CA-modified iron oxide removed about 100% phosphorus. • Precipitation of phosphate and Fe {sup n+} was the main removal mechanism. - Abstract: In this study, citric acid (CA) was employed as a low-molecule organic acid to influence the adsorption performance of phosphorus by as-obtained magnetite. The factors including initial phosphate concentrations, dosage of citric acid, pH value, ion strength, contact time and temperature were examined in detail. Results indicated that the dissolution of anion sodium dodecyl sulfate (SDS) covering on surface of magnetite, a slight decrease of Fe level and a superior structure of magnetite after CA modification occurred. The pH-dependence of phosphate adsorption was impeded and the surface potential of magnetite positively increased at pH > 5.0 when CA was added. Non-linear regression Langmuir-Freundlich model was fitted well in thermodynamics, and the opposite adsorption process as a function of temperatures with or without CA addition was due to the decrease of active energy and active mobility of phosphate ion. Finally, the declining adsorption efficiency with increasing cycles was observed while phosphate removal was approximately finished and had small change with 0.05 and 0.1 M of CA addition. Those improvements of removal efficiency of phosphorus by modified iron oxide were because of the removal of anionic SDS that increased the surface positive charge, and especially the dissolution of element Fe into solution to form precipitate with phosphorus ions. The enhanced stability of magnetite by CA also promoted the high removal efficiency of phosphorus. These implications of CA on phosphate removal can be extended to the field where

  14. Phosphate decreases urine calcium and increases calcium balance: A meta-analysis of the osteoporosis acid-ash diet hypothesis

    Directory of Open Access Journals (Sweden)

    Eliasziw Michael

    2009-09-01

    Full Text Available Abstract Background The acid-ash hypothesis posits that increased excretion of "acidic" ions derived from the diet, such as phosphate, contributes to net acidic ion excretion, urine calcium excretion, demineralization of bone, and osteoporosis. The public is advised by various media to follow an alkaline diet to lower their acidic ion intakes. The objectives of this meta-analysis were to quantify the contribution of phosphate to bone loss in healthy adult subjects; specifically, a to assess the effect of supplemental dietary phosphate on urine calcium, calcium balance, and markers of bone metabolism; and to assess whether these affects are altered by the b level of calcium intake, c the degree of protonation of the phosphate. Methods Literature was identified through computerized searches regarding phosphate with surrogate and/or direct markers of bone health, and was assessed for methodological quality. Multiple linear regression analyses, weighted for sample size, were used to combine the study results. Tests of interaction included stratification by calcium intake and degree of protonation of the phosphate supplement. Results Twelve studies including 30 intervention arms manipulated 269 subjects' phosphate intakes. Three studies reported net acid excretion. All of the meta-analyses demonstrated significant decreases in urine calcium excretion in response to phosphate supplements whether the calcium intake was high or low, regardless of the degree of protonation of the phosphate supplement. None of the meta-analyses revealed lower calcium balance in response to increased phosphate intakes, whether the calcium intake was high or low, or the composition of the phosphate supplement. Conclusion All of the findings from this meta-analysis were contrary to the acid ash hypothesis. Higher phosphate intakes were associated with decreased urine calcium and increased calcium retention. This meta-analysis did not find evidence that phosphate intake

  15. Administering different levels of parenteral phosphate and amino acids did not influence growth in extremely preterm infants

    DEFF Research Database (Denmark)

    Thomsen, Katrine Moe; Beck-Nielsen, Signe Sparre; Lando, Ane

    2015-01-01

    AIM: When a new high amino acid parenteral nutrition (PN) solution was introduced to our hospital, a design error led to decreased phosphate levels. This prompted us to examine the effect of three different PN solutions on plasma phosphate, plasma calcium and weight increases on extremely preterm...

  16. Determination of cellular nicotinic acid-adenine dinucleotide phosphate (NAADP) levels.

    OpenAIRE

    Churamani, Dev; Carrey, Elizabeth A; Dickinson, George D.; Patel, Sandip

    2004-01-01

    Nicotinic acid-adenine dinucleotide phosphate (NAADP) is fast emerging as a new intracellular Ca2+-mobilizing messenger. In sea urchin egg homogenates, binding of NAADP to its receptor is not readily reversible; hence, prior incubation with low concentrations of NAADP is more effective in inhibiting subsequent binding of radiolabelled NAADP than incubating the preparation with the two ligands simultaneously [Patel, Churchill and Galione (2000) Biochem. J. 352, 725-729]. We extend this finding...

  17. Immobilization of Zn, Cu, and Pb in contaminated soils using phosphate rock and phosphoric acid

    Energy Technology Data Exchange (ETDEWEB)

    Cao Xinde [School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)] [Soil and Water Science Department, University of Florida, Gainesville, FL 32611 (United States); Wahbi, Ammar [Soil Science Department, Faculty of Agriculture, University of Aleppo, Aleppo (Syrian Arab Republic); Ma, Lena, E-mail: lqma@ufl.edu [Soil and Water Science Department, University of Florida, Gainesville, FL 32611 (United States); Li Bing; Yang Yongliang [National Research Center for Geoanalysis, Beijing 100037 (China)

    2009-05-30

    Considerable research has been done on P-induced Pb immobilization in Pb-contaminated soils. However, application of P to soils contaminated with multiple heavy metals is limited. The present study examined effectiveness of phosphoric acid (PA) and/or phosphate rock (PR) in immobilizing Pb, Cu, and Zn in two contaminated soils. The effectiveness was evaluated using water extraction, plant uptake, and a simple bioaccessibility extraction test (SBET) mimicking metal uptake in the acidic environment of human stomach. The possible mechanisms for metal immobilization were elucidated using X-ray diffraction, scanning electron microscopy, and chemical speciation program Visual MINTEQ. Compared to the control, all P amendments significantly reduced Pb water solubility, phytoavailability, and bioaccessibility by 72-100%, 15-86%, and 28-92%, respectively. The Pb immobilization was probably attributed to the formation of insoluble Pb phosphate minerals. Phosphorus significantly reduced Cu and Zn water solubility by 31-80% and 40-69%, respectively, presumably due to their sorption on minerals (e.g., calcite and phosphate phases) following CaO addition. However, P had little effect on the Cu and Zn phytoavailability; while the acid extractability of Cu and Zn induced by SBET (pH 2) were even elevated by up to 48% and 40%, respectively, in the H{sub 3}PO{sub 4} treatments (PA and PR + PA). Our results indicate that phosphate was effective in reducing Pb availability in terms of water solubility, bioaccessibility, and phytoavailability. Caution should be exercised when H{sub 3}PO{sub 4} was amended to the soil co-contaminated with Cu and Zn since the acidic condition of SBET increased Cu and Zn bioaccessibility though their water solubility was reduced.

  18. Effect of Hydrochloric Acid (HCl) on Synthesis and Anisotropic Phenomena of Triglycine Phosphate (TGP) Single Crystals

    OpenAIRE

    Meera, M R; Rayar, SL; Bena Jothy, V,

    2017-01-01

    International audience; Effect of Sulphuric acid (H2SO4) addition on the growth of triglycine phosphate (TGP) crystal has been studied from the aqueous solution by slow evaporation technique. The characteristics absorption bands of pure and H2SO4 admixtured TGP crystals are confirmed by FTIR spectra. UV-visible transmittance spectra were recorded for the samples to analyze the transparency of the grown crystals. The composition of pure and doped TGP crystals have been confirmed by EDAX analys...

  19. Competitive adsorption involving phosphate and benzenecarboxylic acids on goethite--effects of molecular structures.

    Science.gov (United States)

    Lindegren, Malin; Persson, Per

    2010-03-01

    The competitive adsorption between phosphate and either one of seven benzenecarboxylates (benzoate, phthalate, trimellitate, trimesoate, hemimellitate, pyromellitate, and mellitate) on the surfaces of fine-particulate goethite (alpha-FeOOH) was investigated as a function of pH. The series of ligands contained molecules with an increasing number of functional groups as well as three structural isomers of the tricarboxylates. Thus, the effects of both the number of carboxylate groups and the relative positions of these groups on the competitive efficiency toward phosphate were probed in this study. Quantitative adsorption experiments in batch mode and infrared spectroscopy were collectively used to evaluate the competitive adsorption reactions. Under the conditions probed, mono- and dicarboxylates had no detectable effect on phosphate adsorption whereas the ligands containing three or more carboxylate groups were able to partially outcompete phosphate. However, the pH dependency and the extent of these competitive effects were strongly dependent on the structure and composition of the benzenecarboxylate. The collective results showed that it was the competition for hydrogen-bonding surface sites rather than inner sphere surface sites that primarily determined the outcome of the competitive adsorption experiments, and it was the ability of the organic ligand to act as hydrogen-bonding acceptor and/or donor in various parts of the pH range that also determined the competitive pH dependency. The importance of H-bonding for the competitive adsorption between phosphate and benzenecarboxylic acids suggested that H-bonding interactions contributed substantially to the stabilities of both the adsorbed benzenecarboxylates and the phosphate ions and that these interactions were structurally specific; i.e., they were sensitive to the locations and the directional properties of the H-acceptor and H-donor surface sites. 2009 Elsevier Inc. All rights reserved.

  20. A novel biodegradable nicotinic acid/calcium phosphate composite coating on Mg-3Zn alloy

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yingwei, E-mail: ywsong@imr.ac.cn; Shan, Dayong; Han, En-Hou

    2013-01-01

    A novel biodegradable composite coating is prepared to reduce the biodegradation rate of Mg-3Zn alloy. The Mg-3Zn substrate is first immersed into 0.02 mol L{sup -1} nicotinic acid (NA) solution, named as vitamin B{sub 3}, to obtain a pretreatment film, and then the electrodeposition of calcium phosphate coating with ultrasonic agitation is carried out on the NA pretreatment film to obtain a NA/calcium phosphate composite coating. Surface morphology is observed by scanning electron microscopy (SEM). Chemical composition is determined by X-ray diffraction (XRD) and EDX. Protection property of the coatings is evaluated by electrochemical tests. The biodegradable behavior is investigated by immersion tests. The results indicate that a thin but compact bottom layer can be obtained by NA pretreatment. The electrodeposition calcium phosphate coating consists of many flake particles and ultrasonic agitation can greatly improve the compactness of the coating. The composite coating is biodegradable and can reduce the biodegradation rate of Mg alloys in stimulated body fluid (SBF) for twenty times. The biodegradation process of the composite coating can be attributed to the gradual dissolution of the flake particles into chippings. - Highlights: Black-Right-Pointing-Pointer NA/calcium phosphate composite coating is prepared to protect Mg-3Zn alloy implant. Black-Right-Pointing-Pointer Nicotinic acid (vitamin B{sub 3}) is available to obtain a protective bottom film. Black-Right-Pointing-Pointer Ultrasonic agitation greatly improves the compactness of calcium phosphate coating. Black-Right-Pointing-Pointer The composite coating can reduce the biodegradation rate of Mg-3Zn twenty times. Black-Right-Pointing-Pointer The composite coating is biodegraded by the dissolution of flakes into chippings.

  1. Acid gradient across plasma membrane can drive phosphate bond synthesis in cancer cells: acidic tumor milieu as a potential energy source.

    Science.gov (United States)

    Dhar, Gautam; Sen, Suvajit; Chaudhuri, Gautam

    2015-01-01

    Aggressive cancers exhibit an efficient conversion of high amounts of glucose to lactate accompanied by acid secretion, a phenomenon popularly known as the Warburg effect. The acidic microenvironment and the alkaline cytosol create a proton-gradient (acid gradient) across the plasma membrane that represents proton-motive energy. Increasing experimental data from physiological relevant models suggest that acid gradient stimulates tumor proliferation, and can also support its energy needs. However, direct biochemical evidence linking extracellular acid gradient to generation of intracellular ATP are missing. In this work, we demonstrate that cancer cells can synthesize significant amounts of phosphate-bonds from phosphate in response to acid gradient across plasma membrane. The noted phenomenon exists in absence of glycolysis and mitochondrial ATP synthesis, and is unique to cancer. Biochemical assays using viable cancer cells, and purified plasma membrane vesicles utilizing radioactive phosphate, confirmed phosphate-bond synthesis from free phosphate (Pi), and also localization of this activity to the plasma membrane. In addition to ATP, predominant formation of pyrophosphate (PPi) from Pi was also observed when plasma membrane vesicles from cancer cells were subjected to trans-membrane acid gradient. Cancer cytosols were found capable of converting PPi to ATP, and also stimulate ATP synthesis from Pi from the vesicles. Acid gradient created through glucose metabolism by cancer cells, as observed in tumors, also proved critical for phosphate-bond synthesis. In brief, these observations reveal a role of acidic tumor milieu as a potential energy source and may offer a novel therapeutic target.

  2. Continuous venovenous hemodiafiltration with a low citrate dose regional anticoagulation protocol and a phosphate-containing solution: effects on acid-base status and phosphate supplementation needs.

    Science.gov (United States)

    Morabito, Santo; Pistolesi, Valentina; Tritapepe, Luigi; Vitaliano, Elio; Zeppilli, Laura; Polistena, Francesca; Fiaccadori, Enrico; Pierucci, Alessandro

    2013-10-25

    Recent guidelines suggest the adoption of regional citrate anticoagulation (RCA) as first choice CRRT anticoagulation modality in patients without contraindications for citrate. Regardless of the anticoagulation protocol, hypophosphatemia represents a potential drawback of CRRT which could be prevented by the adoption of phosphate-containing CRRT solutions. The aim was to evaluate the effects on acid-base status and phosphate supplementation needs of a new RCA protocol for Continuous Venovenous Hemodiafiltration (CVVHDF) combining the use of citrate with a phosphate-containing CRRT solution. To refine our routine RCA-CVVH protocol (12 mmol/l citrate, HCO3- 32 mmol/l replacement fluid) (protocol A) and to prevent CRRT-related hypophosphatemia, we introduced a new RCA-CVVHDF protocol (protocol B) combining an 18 mmol/l citrate solution with a phosphate-containing dialysate/replacement fluid (HCO3- 30 mmol/l, Phosphate 1.2). A low citrate dose (2.5-3 mmol/l) and a higher than usual target circuit-Ca(2+) (≤ 0.5 mmol/l) have been adopted. Two historical groups of heart surgery patients (n = 40) underwent RCA-CRRT with protocol A (n = 20, 102 circuits, total running time 5283 hours) or protocol B (n = 20, 138 circuits, total running time 7308 hours). Despite higher circuit-Ca(2+) in protocol B (0.37 vs 0.42 mmol/l, p patients while protocol B ensured appropriate acid-base balance without additional interventions: pH 7.43 (7.40-7.46), Bicarbonate 25.3 (23.8-26.6) mmol/l, BE 0.9 (-0.8 to +2.4); median (IQR). No episodes of clinically relevant metabolic alkalosis, requiring modifications of RCA-CRRT settings, were observed. Phosphate supplementation was needed in all group A patients (3.4 ± 2.4 g/day) and in only 30% of group B patients (0.5 ± 1.5 g/day). Hypophosphatemia developed in 75% and 30% of group A and group B patients, respectively. Serum phosphate was significantly higher in protocol B patients (P < 0.001) and, differently to protocol A, appeared to be

  3. A hybrid composite system of biphasic calcium phosphate granules loaded with hyaluronic acid-gelatin hydrogel for bone regeneration.

    Science.gov (United States)

    Faruq, Omar; Kim, Boram; Padalhin, Andrew R; Lee, Gun Hee; Lee, Byong-Taek

    2017-10-01

    An ideal bone substitute should be made of biocompatible materials that mimic the structure, characteristics, and functions of natural bone. Many researchers have worked on the fabrication of different bone scaffold systems including ceramic-polymer hybrid system. In the present study, we incorporated hyaluronic acid-gelatin hydrogel to micro-channeled biphasic calcium phosphate granules as a carrier to improve cell attachment and proliferation through highly interconnected porous structure. This hybrid system is composed of ceramic biphasic calcium phosphate granules measuring 1 mm in diameter with seven holes and hyaluronic acid-gelatin hydrogel. This combination of biphasic calcium phosphate and hyaluronic acid-gelatin retained suitable characteristics for bone regeneration. The resulting scaffold had a porosity of 56% with a suitable pore sizes. The mechanical strength of biphasic calcium phosphate granule increased after loading hyaluronic acid-gelatin from 4.26 ± 0.43 to 6.57 ± 0.25 MPa, which is highly recommended for cancellous bone substitution. Swelling and degradation rates decreased in the hybrid scaffold compared to hydrogel due to the presence of granules in hybrid scaffold. In vitro cytocompatibility studies were observed by preosteoblasts (MC3T3-E1) cell line and the result revealed that biphasic calcium phosphate/hyaluronic acid-gelatin significantly increased cell growth and proliferation compared to biphasic calcium phosphate granules. Analysis of micro-computed tomography data and stained tissue sections from the implanted samples showed that the hybrid scaffold had good osseointegration and better bone formation in the scaffold one and two months postimplantation. Histological section confirmed the formation of dense collagenous tissue and new bone in biphasic calcium phosphate/hyaluronic acid-gelatin scaffolds at two months. Our study demonstrated that such hybrid biphasic calcium phosphate/hyaluronic acid-gelatin scaffold is a

  4. Strong and Biostable Hyaluronic Acid-Calcium Phosphate Nanocomposite Hydrogel via in Situ Precipitation Process.

    Science.gov (United States)

    Jeong, Seol-Ha; Koh, Young-Hag; Kim, Suk-Wha; Park, Ji-Ung; Kim, Hyoun-Ee; Song, Juha

    2016-03-14

    Hyaluronic acid (HAc) hydrogel exhibits excellent biocompatibility, but it has limited biomedical application due to its poor biomechanical properties as well as too-fast enzymatic degradation. In this study, we have developed an in situ precipitation process for the fabrication of a HAc-calcium phosphate nanocomposite hydrogel, after the formation of the glycidyl methacrylate-conjugated HAc (GMHA) hydrogels via photo-cross-linking, to improve the mechanical and biological properties under physiological conditions. In particular, our process facilitates the rapid incorporation of calcium phosphate (CaP) nanoparticles of uniform size and with minimal agglomeration into a polymer matrix, homogeneously. Compared with pure HAc, the nanocomposite hydrogels exhibit improved mechanical behavior. Specifically, the shear modulus is improved by a factor of 4. The biostability of the nanocomposite hydrogel was also significantly improved compared with that of pure HAc hydrogels under both in vitro and in vivo conditions.

  5. Comparison of efficacy of the phosphate binders nicotinic acid and sevelamer hydrochloride in hemodialysis patients

    Directory of Open Access Journals (Sweden)

    Farrokhlagha Ahmadi

    2012-01-01

    Full Text Available Hyperphosphatemia is a significant risk factor for the development of ectopic calcification and coronary artery diseases in patients on hemodialysis (HD, and must be controlled with the use of phosphate binders. Studies comparing the effects of sevelamer and nicotinic acid, both similar non-calcium and non-aluminum phosphate binders, are not available. In this study, 40 patients on HD with a serum phosphorus level of more than 6 mg/dL were enrolled. After a two week washout period without phosphate binders, the patients were randomly divided into two equal groups (n = 20 and were started on nicotinic acid or sevelamer for a period of four weeks. The dose of nicotinic acid used was 500 mg and that of sevelamer was 1600 mg daily. Blood samples were drawn for the measurement of the total calcium (Ca, phosphorus (P, alkaline phosphatase (ALP, triglyceride (TG, total cholesterol (Chol, high-density lipoprotein (HDL, low-density lipoprotein (LDL, uric acid and parathyroid hormone (PTH. Patients receiving sevelamer showed a significant reduction in serum P level (2.2 ± 0.69 mg/dL; P <0.0001 in comparison with the nicotinic acid group (1.7 ± 1.06 mg/dL; P = 0.004. Reduction in the Ca-P product was significantly different in the two groups; in the sevelamer group, it was 21 ± 7; (P <0.0001 while in the nicotinic acid group, it was 16 ± 11 (P = 0.007. Also, patients on sevelamer showed greater reduction in the mean TG level (38.9 ± 92 mg/dL; P = 0.005. No significant changes were observed in the mean serum Ca, total Chol, HDL, LDL, ALP and iPTH levels in the two study groups. Our short-term study suggests that although nicotinic acid reduced hyperphosphatemia, sevelamer showed higher efficacy in controlling hyperphosphatemia as well as the Ca-P product.

  6. Acid-base properties of sorbents based on zirconium(IV) phosphates

    Energy Technology Data Exchange (ETDEWEB)

    Bekrenev, A.V. [Research Center of Environmental Safety, St. Petersburg (Russian Federation); Pyartman, A.K. [St. Petersburg Institute of Technology (Russian Federation)

    1995-11-01

    The objective of this work was to investigate the acid-base properties of materials based on zirconium(IV) phosphate and diphosphate and to calculate the equilibrium constants for corresponding heterogeneous reactions of binary ion exchange, that is, to calculate the characteristics of the ion-exchange properties for use in calculating more complicated ion-exchange equilibria. The objects of investigation were zirconium(IV) hydroxyphosphate (ZHP) and zirconium(IV) diphosphate (ZDP), as well as composite materials based on said compounds and a porous support material.

  7. 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

  8. Phosphate solubilization and acid phosphatase activity of Serratia sp. isolated from mangrove soil of Mahanadi river delta, Odisha, India

    Directory of Open Access Journals (Sweden)

    B.C. Behera

    2017-06-01

    Full Text Available Phosphorus is an essential element for all life forms. Phosphate solubilizing bacteria are capable of converting phosphate into a bioavailable form through solubilization and mineralization processes. Hence in the present study a phosphate solubilizing bacterium, PSB-37, was isolated from mangrove soil of the Mahanadi river delta using NBRIP-agar and NBRIP-BPB broth containing tricalcium phosphate as the phosphate source. Based on phenotypic and molecular characterization, the strain was identified as Serratia sp. The maximum phosphate solubilizing activity of the strain was determined to be 44.84 μg/ml, accompanied by a decrease in pH of the growth medium from 7.0 to 3.15. During phosphate solubilization, various organic acids, such as malic acid (237 mg/l, lactic acid (599.5 mg/l and acetic acid (5.0 mg/l were also detected in the broth culture through HPLC analysis. Acid phosphatase activity was determined by performing p-nitrophenyl phosphate assay (pNPP of the bacterial broth culture. Optimum acid phosphatase activity was observed at 48 h of incubation (76.808 U/ml, temperature of 45 °C (77.87 U/ml, an agitation rate of 100 rpm (80.40 U/ml, pH 5.0 (80.66 U/ml and with glucose as a original carbon source (80.6 U/ml and ammonium sulphate as a original nitrogen source (80.92 U/ml. Characterization of the partially purified acid phosphatase showed maximum activity at pH 5.0 (85.6 U/ml, temperature of 45 °C (97.87 U/ml and substrate concentration of 2.5 mg/ml (92.7 U/ml. Hence the present phosphate solubilizing and acid phosphatase production activity of the bacterium may have probable use for future industrial, agricultural and biotechnological application.

  9. Biochar Enhances Aspergillus niger Rock Phosphate Solubilization by Increasing Organic Acid Production and Alleviating Fluoride Toxicity

    Science.gov (United States)

    Mendes, Gilberto de Oliveira; Zafra, David Lopez; Vassilev, Nikolay Bojkov; Silva, Ivo Ribeiro; Ribeiro, José Ivo

    2014-01-01

    During fungal rock phosphate (RP) solubilization, a significant quantity of fluoride (F−) is released together with phosphorus (P), strongly inhibiting the process. In the present study, the effect of two F− adsorbents [activated alumina (Al2O3) and biochar] on RP solubilization by Aspergillus niger was examined. Al2O3 adsorbed part of the F− released but also adsorbed soluble P, which makes it inappropriate for microbial RP solubilization systems. In contrast, biochar adsorbed only F− while enhancing phosphate solubilization 3-fold, leading to the accumulation of up to 160 mg of P per liter. By comparing the values of F− measured in solution at the end of incubation and those from a predictive model, it was estimated that up to 19 mg of F− per liter can be removed from solution by biochar when added at 3 g liter−1 to the culture medium. Thus, biochar acted as an F− sink during RP solubilization and led to an F− concentration in solution that was less inhibitory to the process. In the presence of biochar, A. niger produced larger amounts of citric, gluconic, and oxalic acids, whether RP was present or not. Our results show that biochar enhances RP solubilization through two interrelated processes: partial removal of the released F− and increased organic acid production. Given the importance of organic acids for P solubilization and that most of the RPs contain high concentrations of F−, the proposed solubilization system offers an important technological improvement for the microbial production of soluble P fertilizers from RP. PMID:24610849

  10. Revegetation of Acid Rock Drainage (ARD) Producing Slope Surface Using Phosphate Microencapsulation and Artificial Soil

    Science.gov (United States)

    Kim, Jae Gon

    2017-04-01

    Oxidation of sulfides produces acid rock drainage (ARD) upon their exposure to oxidation environment by construction and mining activities. The ARD causes the acidification and metal contamination of soil, surface water and groundwater, the damage of plant, the deterioration of landscape and the reduction of slope stability. The revegetation of slope surface is one of commonly adopted strategies to reduce erosion and to increase slope stability. However, the revegetation of the ARD producing slope surface is frequently failed due to its high acidity and toxic metal content. We developed a revegetation method consisting of microencapsualtion and artificial soil in the laboratory. The revegetation method was applied on the ARD producing slope on which the revegetation using soil coverage and seeding was failed and monitored the plant growth for one year. The phosphate solution was applied on sulfide containing rock to form stable Fe-phosphate mineral on the surface of sulfide, which worked as a physical barrier to prevent contacting oxidants such as oxygen and Fe3+ ion to the sulfide surface. After the microencapsulation, two artificial soil layers were constructed. The first layer containing organic matter, dolomite powder and soil was constructed at 2 cm thickness to neutralize the rising acidic capillary water from the subsurface and to remove the dissolved oxygen from the percolating rain water. Finally, the second layer containing seeds, organic matter, nutrients and soil was constructed at 3 cm thickness on the top. After application of the method, the pH of the soil below the artificial soil layer increased and the ARD production from the rock fragments reduced. The plant growth showed an ordinary state while the plant died two month after germination for the previous revegetation trial. No soil erosion occurred from the slope during the one year field test.

  11. Polyaspartic Acid Concentration Controls the Rate of Calcium Phosphate Nanorod Formation in High Concentration Systems

    Energy Technology Data Exchange (ETDEWEB)

    Krogstad, Daniel V. [Biosystems and; Wang, Dongbo [Biosystems and; Lin-Gibson, Sheng [Biosystems and

    2017-08-31

    Polyelectrolytes are known to greatly affect calcium phosphate (CaP) mineralization. The reaction kinetics as well as the CaP phase, morphology and aggregation state depend on the relative concentrations of the polyelectrolyte and the inorganic ions in a complex, nonlinear manner. This study examines the structural evolution and kinetics of polyaspartic acid (pAsp) directed CaP mineralization at high concentrations of polyelectrolytes, calcium, and total phosphate (19–30 mg/mL pAsp, 50–100 mM Ca2+, Ca/P = 2). Using a novel combination of characterization techniques including cryogenic transmission electron microscopy (cryo-TEM), spectrophotometry, X-ray total scattering pair distribution function analysis, and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), it was determined that the CaP mineralization occurred over four transition steps. The steps include the formation of aggregates of pAsp stabilized CaP spherical nanoparticles (sNP), crystallization of sNP, oriented attachment of the sNP into nanorods, and further crystallization of the nanorods. The intermediate aggregate sizes and the reaction kinetics were found to be highly polymer concentration dependent while the sizes of the particles were not concentration dependent. This study demonstrates the complex role of pAsp in controlling the mechanism as well as the kinetics of CaP mineralization.

  12. Triphenyl phosphate-induced developmental toxicity in zebrafish: potential role of the retinoic acid receptor.

    Science.gov (United States)

    Isales, Gregory M; Hipszer, Rachel A; Raftery, Tara D; Chen, Albert; Stapleton, Heather M; Volz, David C

    2015-04-01

    Using zebrafish as a model, we previously reported that developmental exposure to triphenyl phosphate (TPP) - a high-production volume organophosphate-based flame retardant - results in dioxin-like cardiac looping impairments that are independent of the aryl hydrocarbon receptor. Using a pharmacologic approach, the objective of this study was to investigate the potential role of retinoic acid receptor (RAR) - a nuclear receptor that regulates vertebrate heart morphogenesis - in mediating TPP-induced developmental toxicity in zebrafish. We first revealed that static exposure of zebrafish from 5-72h post-fertilization (hpf) to TPP in the presence of non-toxic concentrations of an RAR antagonist (BMS493) significantly enhanced TPP-induced toxicity (relative to TPP alone), even though identical non-toxic BMS493 concentrations mitigated retinoic acid (RA)-induced toxicity. BMS493-mediated enhancement of TPP toxicity was not a result of differential TPP uptake or metabolism, as internal embryonic doses of TPP and diphenyl phosphate (DPP) - a primary TPP metabolite - were not different in the presence or absence of BMS493. Using real-time PCR, we then quantified the relative change in expression of cytochrome P450 26a1 (cyp26a1) - a major target gene for RA-induced RAR activation in zebrafish - and found that RA and TPP exposure resulted in a ∼5-fold increase and decrease in cyp26a1 expression, respectively, relative to vehicle-exposed embryos. To address whether TPP may interact with human RARs, we then exposed Chinese hamster ovary cells stably transfected with chimeric human RARα-, RARβ-, or RARγ to TPP in the presence of RA, and found that TPP significantly inhibited RA-induced luciferase activity in a concentration-dependent manner. Overall, our findings suggest that zebrafish RARs may be involved in mediating TPP-induced developmental toxicity, a mechanism of action that may have relevance to humans. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Bile acids and sphingosine-1-phosphate receptor 2 in hepatic lipid metabolism

    Directory of Open Access Journals (Sweden)

    Eric Kwong

    2015-03-01

    Full Text Available The liver is the central organ involved in lipid metabolism. Dyslipidemia and its related disorders, including non-alcoholic fatty liver disease (NAFLD, obesity and other metabolic diseases, are of increasing public health concern due to their increasing prevalence in the population. Besides their well-characterized functions in cholesterol homoeostasis and nutrient absorption, bile acids are also important metabolic regulators and function as signaling hormones by activating specific nuclear receptors, G-protein coupled receptors, and multiple signaling pathways. Recent studies identified a new signaling pathway by which conjugated bile acids (CBA activate the extracellular regulated protein kinases (ERK1/2 and protein kinase B (AKT signaling pathway via sphingosine-1-phosphate receptor 2 (S1PR2. CBA-induced activation of S1PR2 is a key regulator of sphingosine kinase 2 (SphK2 and hepatic gene expression. This review focuses on recent findings related to the role of bile acids/S1PR2-mediated signaling pathways in regulating hepatic lipid metabolism.

  14. Bile acids and sphingosine-1-phosphate receptor 2 in hepatic lipid metabolism.

    Science.gov (United States)

    Kwong, Eric; Li, Yunzhou; Hylemon, Phillip B; Zhou, Huiping

    2015-03-01

    The liver is the central organ involved in lipid metabolism. Dyslipidemia and its related disorders, including non-alcoholic fatty liver disease (NAFLD), obesity and other metabolic diseases, are of increasing public health concern due to their increasing prevalence in the population. Besides their well-characterized functions in cholesterol homoeostasis and nutrient absorption, bile acids are also important metabolic regulators and function as signaling hormones by activating specific nuclear receptors, G-protein coupled receptors, and multiple signaling pathways. Recent studies identified a new signaling pathway by which conjugated bile acids (CBA) activate the extracellular regulated protein kinases (ERK1/2) and protein kinase B (AKT) signaling pathway via sphingosine-1-phosphate receptor 2 (S1PR2). CBA-induced activation of S1PR2 is a key regulator of sphingosine kinase 2 (SphK2) and hepatic gene expression. This review focuses on recent findings related to the role of bile acids/S1PR2-mediated signaling pathways in regulating hepatic lipid metabolism.

  15. Phosphate tuned copper electrodeposition and promoted formic acid selectivity for carbon dioxide reduction

    DEFF Research Database (Denmark)

    Zhao, Jian; Sun, Libo; Canepa, Silvia

    2017-01-01

    (II) concentration and the electrodeposition current at identical applied potentials. We also found that the electrodeposition of Cu in the presence of phosphate generates Cu-oxyo/hydroxyo-phosphate species on the deposited copper surface. The modified electrodes with phosphate species exhibit higher selectivity...

  16. rhBMP-2 release from injectable poly(DL-lactic-co-glycolic acid)/calcium-phosphate cement composites.

    NARCIS (Netherlands)

    Ruhe, P.Q.; Hedberg, E.L.; Padron, N.T.; Spauwen, P.H.M.; Jansen, J.A.; Mikos, A.G.

    2003-01-01

    BACKGROUND: In bone tissue engineering, poly(DL-lactic-co-glycolic acid) (PLGA) microparticles are frequently used as a delivery vehicle for bioactive molecules. Calcium phosphate cement is an injectable, osteoconductive, and degradable bone cement that sets in situ. The objective of this study was

  17. The influence of gibberellin on the level of nucleic acids and other phosphate fractions in maize seedlings

    Directory of Open Access Journals (Sweden)

    P. Masłowski

    2015-01-01

    Full Text Available Treatment of maize seedes with GA3 increased the content of water, the phosphate acid soluble fraction, the phospholipid fraction and the low molecular weight r-RNA, s-RNA, DNA-RNA fractions in 5-days-old seedlings. On the other hand, the contents of RNA and DNA in such seedlings decreased.

  18. Simultaneous removal of ammonium and phosphate by zeolite synthesized from coal fly ash as influenced by acid treatment.

    Science.gov (United States)

    Zhang, Bao-Hua; Wu, De-Yi; Wang, Chong; He, Sheng-Bing; Zhang, Zhen-Jia; Kong, Hai-Nan

    2007-01-01

    Zeolite synthesized from fly ash (ZFA) without modification is not efficient for the purification of NH4+ and phosphate at low concentrations that occur in real effluents, despite the high potential removal capacity. To develop an effective technique to enhance the removal efficiency of ammonium and phosphate at low concentrations, ZFA was modified with acid treatment and the simultaneous removal of ammonium and phosphate in a wide range of concentration was investigated. It was seen that when compared with untreated ZFA, only the treatment by 0.01 mol/L of H2SO4 significantly improved the removal efficiency of ammonium at low initial concentrations. The behavior was well explained by the pH effect. Treatment by more concentrated H2SO4 led to the deterioration of the ZFA structure and a decrease in the cation exchange capacity. Treatment by 0.01 mol/L H2SO4 improved the removal efficiency of phosphate by ZFA at all initial P concentrations, while the treatment by concentrated H2SO4 (> or = 0.9 mol/L) resulted in a limited maximum phosphate immobilization capacity (PIC). It was concluded that through a previous mild acid treatment (e.g. 0.01 mol/L of H2SO4), ZFA can be used in the simultaneous removal of NH4+ and P at low concentrations in simulating real effluent.

  19. 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

  20. Skin penetration and retention of L-ascorbic acid 2-phosphate using multilamellar vesicles.

    Science.gov (United States)

    Yoo, Juno; Shanmugam, Srinivasan; Song, Chung-Kil; Kim, Dae-Duk; Choi, Han-Gon; Yong, Chul-Soon; Woo, Jong-Soo; Yoo, Bong Kyu

    2008-12-01

    Transdermal formulation of L-ascorbic acid 2-phosphate magnesium salt (A2P) was prepared using multilamellar vesicles (MLV). A2P was either physically mixed with or entrapped into three different MLVs of neutral, cationic, and anionic liposome vesicles. For the preparation of neutral MLVs, phosphatidylcholine (PC) and cholesterol (CH) were used. For cationic and anionic MLVs, dioleoyl-trimethylammonium-propane and dimyristoyl glycerophosphate were added as surface charge inducers, respectively, in addition to PC and CH. Particle size of the three A2P-loaded MLVs was submicron, and polydispersity index revealed homogenous distribution of the prepared MLVs except neutral ones. Skin penetration study with hairless mouse skin showed that both physical mixtures of A2P with empty MLVs and A2P-loaded MLVs increased penetration of the drug compared to aqueous A2P solution. During the penetration, however, significant amount of the drug was metabolized into L-ascorbic acid, which has no beneficial effect on stimulation of hair growth. Out of the physical mixtures and A2P-loaded MLVs tested, physical mixture of A2P with empty cationic MLV resulted in the greatest skin penetration and retention in hairless mouse skin.

  1. Release of Ciprofloxacin-HCl and Dexamethasone Phosphate by Hyaluronic Acid Containing Silicone Polymers

    Science.gov (United States)

    Nguyen, Darrene; Hui, Alex; Weeks, Andrea; Heynen, Miriam; Joyce, Elizabeth; Sheardown, Heather; Jones, Lyndon

    2012-01-01

    The purpose of this study was to determine the effect of the covalent incorporation of hyaluronic acid (HA) into conventional hydrogel and hydrogels containing silicone as models for contact lens materials on the uptake and release of the fluoroquinolone antibiotic ciprofloxacin and the anti-inflammatory steroid dexamethasone phosphate. A 3 mg/mL ciprofloxacin solution (0.3% w/v) and a 1 mg/mL dexamethasone phosphate solution (0.1%) was prepared in borate buffered saline. Three hydrogel material samples (pHEMA; pHEMA TRIS; DMAA TRIS) were prepared with and without the covalent incorporation of HA of molecular weight (MW) 35 or 132 kDa. Hydrogel discs were punched from a sheet of material with a uniform diameter of 5 mm. Uptake kinetics were evaluated at room temperature by soaking the discs for 24 h. Release kinetics were evaluated by placing the drug-loaded discs in saline at 34 °C in a shaking water bath. At various time points over 6–7 days, aliquots of the release medium were assayed for drug amounts. The majority of the materials tested released sufficient drug to be clinically relevant in an ophthalmic application, reaching desired concentrations for antibiotic or anti-inflammatory activity in solution. Overall, the silicone-based hydrogels (pHEMA TRIS and DMAA TRIS), released lower amounts of drug than the conventional pHEMA material (p < 0.001). Materials with HA MW132 released more ciprofloxacin compared to materials with HA MW35 and lenses without HA (p < 0.02). Some HA-based materials were still releasing the drug after 6 days. PMID:28817003

  2. Release of Ciprofloxacin-HCl and Dexamethasone Phosphate by Hyaluronic Acid Containing Silicone Polymers

    Directory of Open Access Journals (Sweden)

    Lyndon Jones

    2012-04-01

    Full Text Available The purpose of this study was to determine the effect of the covalent incorporation of hyaluronic acid (HA into conventional hydrogel and hydrogels containing silicone as models for contact lens materials on the uptake and release of the fluoroquinolone antibiotic ciprofloxacin and the anti-inflammatory steroid dexamethasone phosphate. A 3 mg/mL ciprofloxacin solution (0.3% w/v and a 1 mg/mL dexamethasone phosphate solution (0.1% was prepared in borate buffered saline. Three hydrogel material samples (pHEMA; pHEMA TRIS; DMAA TRIS were prepared with and without the covalent incorporation of HA of molecular weight (MW 35 or 132 kDa. Hydrogel discs were punched from a sheet of material with a uniform diameter of 5 mm. Uptake kinetics were evaluated at room temperature by soaking the discs for 24 h. Release kinetics were evaluated by placing the drug-loaded discs in saline at 34 °C in a shaking water bath. At various time points over 6–7 days, aliquots of the release medium were assayed for drug amounts. The majority of the materials tested released sufficient drug to be clinically relevant in an ophthalmic application, reaching desired concentrations for antibiotic or anti-inflammatory activity in solution. Overall, the silicone-based hydrogels (pHEMA TRIS and DMAA TRIS, released lower amounts of drug than the conventional pHEMA material (p < 0.001. Materials with HA MW132 released more ciprofloxacin compared to materials with HA MW35 and lenses without HA (p < 0.02. Some HA-based materials were still releasing the drug after 6 days.

  3. Synthesis of lithium iron phosphate/carbon microspheres by using polyacrylic acid coated iron phosphate nanoparticles derived from iron(III) acrylate.

    Science.gov (United States)

    Xu, Dongwei; He, Yan-Bing; Chu, Xiaodong; Ding, Zhaojun; Li, Baohua; He, Jianfu; Du, Hongda; Qin, Xianying; Kang, Feiyu

    2015-03-01

    Lithium iron phosphate/carbon (LiFePO4 /C) microspheres with high rate and cycling performance are synthesized from iron phosphate/polyacrylic acid (FePO4 /PAA) nanoparticles. Iron(III) acrylate is used as a precursor for both the iron and carbon sources. FePO4 nanoparticles are first produced by a coprecipitation reaction. The byproduct, acrylic acid ions, is polymerized in situ to form a uniform PAA layer on the surface of the FePO4 nanoparticles. The as-prepared LiFePO4 /C microspheres are composed of primary nanoparticles with sizes of 40-50 nm. The nanoparticles are fully coated with a thin, uniform carbon layer derived from the decomposition of the PAA layer. The uniform carbon-coating layer cooperates with interstitial and boundary carbon derived from sucrose successfully to construct an excellent interconnecting conductive network in the microspheres. As a result of the unique structure, the as-prepared LiFePO4 /C microspheres display both high electronic and ionic conductivities, which contribute to their high rate performance (162.9 mAh g(-1) at 0.1C and 126.1 mAh g(-1) at 5C) and excellent cycling stability (97.1% of capacity retention after 500 cycles at 5C/5C). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Tris(2-butoxyethyl)phosphate and triethyl phosphate alter embryonic development, hepatic mRNA expression, thyroid hormone levels, and circulating bile acid concentrations in chicken embryos

    Energy Technology Data Exchange (ETDEWEB)

    Egloff, Caroline [National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3 (Canada); Crump, Doug, E-mail: doug.crump@ec.gc.ca [National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3 (Canada); Porter, Emily; Williams, Kim L.; Letcher, Robert J.; Gauthier, Lewis T. [National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3 (Canada); Kennedy, Sean W. [National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3 (Canada); Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5 (Canada)

    2014-09-15

    The organophosphate flame retardants tris(2-butoxyethyl) phosphate (TBOEP) and triethyl phosphate (TEP) are used in a wide range of applications to suppress or delay the ignition and spread of fire. Both compounds have been detected in the environment and TBOEP was recently measured in free-living avian species. In this study, TBOEP and TEP were injected into the air cell of chicken embryos at concentrations ranging from 0 to 45,400 ng/g and 0 to 241,500 ng/g egg, respectively. Pipping success, development, hepatic mRNA expression of 9 target genes, thyroid hormone levels, and circulating bile acid concentrations were determined. Exposure to the highest doses of TBOEP and TEP resulted in negligible detection of the parent compounds in embryonic contents at pipping indicating their complete metabolic degradation. TBOEP exposure had limited effects on chicken embryos, with the exception of hepatic CYP3A37 mRNA induction. TEP exposure decreased pipping success to 68%, altered growth, increased liver somatic index (LSI) and plasma bile acids, and modulated genes associated with xenobiotic and lipid metabolism and the thyroid hormone pathway. Plasma thyroxine levels were decreased at all TEP doses, including an environmentally-relevant concentration (8 ng/g), and gallbladder hypotrophy was evident at ≥ 43,200 ng/g. Tarsus length and circulating thyroxine concentration emerged as potential phenotypic anchors for the modulation of transthyretin mRNA. The increase in plasma bile acids and LSI, gallbladder hypotrophy, and discoloration of liver tissue represented potential phenotypic outcomes associated with modulation of hepatic genes involved with xenobiotic and lipid metabolism. - Highlights: • TBOEP is not embryolethal to chicken embryos. • TEP affected embryonic viability, morphometric endpoints, and thyroid hormone levels. • TEP altered mRNA levels of xenobiotic and lipid metabolism genes. • TEP increased plasma bile acids and caused gallbladder hypotrophy

  5. Fabrication of novel poly(lactic acid)/amorphous magnesium phosphate bionanocomposite fibers for tissue engineering applications via electrospinning

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Huan, E-mail: Huan.Zhou@Rockets.utoledo.edu [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Nabiyouni, Maryam [Department of Bioengineering, The University of Toledo, Toledo, OH (United States); Lin, Boren [Department of Biological Sciences, 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); Department of Surgery (Dentistry), The University of Toledo, Toledo, OH (United States)

    2013-05-01

    Fibrous bionanocomposites consisting of amorphous magnesium phosphate (AMP) nanospheres and polylactic acid (PLA) were fabricated by electrospinning. There are two important signatures of this paper. First, AMP, as an alternative to well-known calcium phosphate (CaP) materials, is added to PLA as the second phase. To the best of our knowledge, it is the first attempt to fabricate magnesium phosphate (MgP)/biopolymer composite. This is made possible by our previously reported research on the successful synthesis of AMP nanospheres via microwave processing. Second, the sustained release of magnesium and phosphate ions from PLA matrix can stimulate a series of cell responses. The structure of the composites and their bone-like apatite-forming abilities in simulated body fluid (SBF) were examined. Additionally, the effects on the proliferation and differentiation of preosteoblast cells were evaluated by performing in vitro cell culture and monitoring markers such as Osteocalcin (OCN), Osteopontin (OPN), Alkaline phosphatase (ALP) and Collagen type-I (Col I) using real-time polymerase chain reaction (PCR). For better dispersion of AMP in the fibers, a surfactant, 12-hydroxysteric acid (HSA), as previously reported in the literature, was used. However, HSA significantly inhibited the proliferation and differentiation of preosteoblast cells, indicating the potential risk in using HSA in the combination of AMP or MgP in tissue engineering applications. - Highlights: ► Amorphous magnesium phosphate (AMP) nanospheres was synthesized. ► AMP/poly lactic acid (PLA) matrix was fabricated via electrospinning. ► AMP was found to be beneficial to MC3T3 preosteoblast cells proliferation. ► Surfactant 12-hydroxysteric acid (HSA) was toxic to preosteoblast cells.

  6. Repression of mineral phosphate solubilizing phenotype in the presence of weak organic acids in plant growth promoting fluorescent pseudomonads.

    Science.gov (United States)

    Patel, Divya K; Murawala, Prayag; Archana, G; Kumar, G Naresh

    2011-02-01

    Two phosphate solubilizing bacteria (PSB), M3 and SP1, were obtained from the rhizosphere of mungbean and sweet potato, respectively and identified as strains of Pseudomonas aeruginosa. Their rock phosphate (RP) solubilizing abilities were found to be due to secretion high amount of gluconic acid. In the presence of malate and succinate, individually and as mixture, the P solubilizing ability of both the strains was considerably reduced. This was correlated with a nearly 80% decrease in the activity of the glucose dehydrogenase (GDH) but not gluconate dehydrogenase (GAD) in both the isolates. Thus, GDH enzyme, catalyzing the periplasmic production of gluconic acid, is under reverse catabolite repression control by organic acids in P. aeruginosa M3 and SP1. This is of relevance in rhizospheric conditions and is a new explanation for the lack of field efficacy of such PSB. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. 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.

  8. Agronomic effectiveness of biofertilizers with phosphate rock, sulphur and Acidithiobacillus for yam bean grown on a Brazilian tableland acidic soil.

    Science.gov (United States)

    Stamford, N P; Santos, P R; Santos, C E S; Freitas, A D S; Dias, S H L; Lira, M A

    2007-04-01

    Phosphate rocks have low available P and soluble P fertilizers have been preferably used in plant crop production, although economic and effective P sources are needed. Experiments were carried out on a Brazilian Typic Fragiudult soil with low available P to evaluate the agronomic effectiveness of phosphate rock (PR) compared with soluble phosphate fertilizer. Yam bean (Pachyrhizus erosus) inoculated with rhizobia (strains NFB 747 and NFB 748) or not inoculated was the test crop. Biofertilizers were produced in field furrows by mixing phosphate rock (PR) and sulphur inoculated with Acidithiobacillus (S+Ac) in different rates (50, 100, 150 and 200 g S kg(-1) PR), with 60 days of incubation. Treatments were carried out with PR; biofertilizers B(50), B(100), B(150), B(200); triple super phosphate (TSP); B(200) without Acidithiobacillus and a control treatment without P application (P(0)). TSP and biofertilizers plus S inoculated with Acidithiobacillus increased plant growth. Soil acidity and available P increased when biofertilizers B(150) and B(200) were applied. We conclude that biofertilizers may be used as P source; however, long term use will reduce soil pH and potentially reduce crop growth.

  9. Methyl phosphate formation as a major degradation mode of direct methanol fuel cells with phosphoric acid based electrolytes

    DEFF Research Database (Denmark)

    Aili, David; Vassiliev, Anton; Jensen, Jens Oluf

    2015-01-01

    Phosphoric acid and phosphoric acid doped polymer membranes are widely used as electrolytes in hydrogen based fuel cells operating at elevated temperatures. Such electrolytes have been explored for direct oxidation of methanol to further increase the versatility of the systems, however......, with demonstrated lifetimes of only a few days to weeks. In this work the methyl phosphate formation from the acid and methanol is identified and proposed to be a major mechanism for the cell degradation. Proton conductivity and fuel cell durability tests validate the mechanism at high methanol contents....

  10. Evaluation of a Recombinant Escherichia coli Strain that Uses the Sarin Simulant Isopropylmethylphosphonic Acid (IMPA) as a Sole Carbon and Phosphate Source

    Science.gov (United States)

    2016-04-01

    PHOSPHATE SOURCE ECBC-TR-1366 Jennifer A. Gibbons Trevor Glaros Steve Harvey Calvin Chue RESEARCH AND TECHNOLOGY DIRECTORATE Paul Demond...Isopropylmethylphosphonic Acid (IMPA) as a Sole Carbon and Phosphate Source 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER WBS...sought the development of a recombinant Escherichia coli strain that utilizes the nerve agent sarin as a sole carbon and phosphate source. To

  11. Radiological, chemical and morphological characterizations of phosphate rock and phosphogypsum from phosphoric acid factories in SW Spain.

    Science.gov (United States)

    Rentería-Villalobos, Marusia; Vioque, Ignacio; Mantero, Juan; Manjón, Guillermo

    2010-09-15

    In this work, radiological, chemical, and also morphological characterization was performed in phosphate rock and phosphogypsum samples, in order to understand the behavior of toxic elements. Characterization was carried out using X-ray diffraction (XRD), X-ray fluorescence (XRF), gamma spectrometry and scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX). Our results show that the phosphate rock was mainly composed of fluorapatite, calcite, perovskite, quartz, magnetite, pyrite and kaolinite, whereas phosphogypsum only exhibited dihydrated calcium sulfate. The activity concentration of U-series radioisotopes in phosphate rock was around 1640 Bq/kg. (226)Ra and (210)Pb tend to be distributed into phosphogypsum by up to 80%, whereas the fraction of U-isotopes is 10%. The most abundant trace elements in phosphate rock were Sr, Cr, V, Zn, Y, Ni and Ba. Some elements, such as Ba, Cd, Cu, La, Pb, Se, Sr, Th and Y, were enriched in the phosphogypsum. This enrichment may be attributed to an additional input associated to the sulfuric acid used for the phosphoric acid production. Furthermore, results from SEM-EDX demonstrated that toxic elements are not distributed homogeneously into phosphogypsum. Most of these elements are concentrated in particles <20 microm of high porosity, and could be easily mobilized by leaching and/or erosion. Copyright 2010 Elsevier B.V. All rights reserved.

  12. Radiological, chemical and morphological characterizations of phosphate rock and phosphogypsum from phosphoric acid factories in SW Spain

    Energy Technology Data Exchange (ETDEWEB)

    Renteria-Villalobos, Marusia, E-mail: marusia@us.es [Applied Nuclear Physics Group, University of Seville, ETS Arquitectura, Departamento de Fisica Aplicada, Avda. Reina Mercedes s/n, 41012 Seville (Spain); Advanced Materials Research Center (CIMAV), Miguel de Cervantes 120, 31109 Chihuahua (Mexico); Vioque, Ignacio, E-mail: ivioque@us.es [Applied Nuclear Physics Group, University of Seville, ETS Arquitectura, Departamento de Fisica Aplicada, Avda. Reina Mercedes s/n, 41012 Seville (Spain); Mantero, Juan, E-mail: manter@us.es [Applied Nuclear Physics Group, University of Seville, ETS Arquitectura, Departamento de Fisica Aplicada, Avda. Reina Mercedes s/n, 41012 Seville (Spain); Manjon, Guillermo, E-mail: manjon@us.es [Applied Nuclear Physics Group, University of Seville, ETS Arquitectura, Departamento de Fisica Aplicada, Avda. Reina Mercedes s/n, 41012 Seville (Spain)

    2010-09-15

    In this work, radiological, chemical, and also morphological characterization was performed in phosphate rock and phosphogypsum samples, in order to understand the behavior of toxic elements. Characterization was carried out using X-ray diffraction (XRD), X-ray fluorescence (XRF), gamma spectrometry and scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX). Our results show that the phosphate rock was mainly composed of fluorapatite, calcite, perovskite, quartz, magnetite, pyrite and kaolinite, whereas phosphogypsum only exhibited dihydrated calcium sulfate. The activity concentration of U-series radioisotopes in phosphate rock was around 1640 Bq/kg. {sup 226}Ra and {sup 210}Pb tend to be distributed into phosphogypsum by up to 80%, whereas the fraction of U-isotopes is 10%. The most abundant trace elements in phosphate rock were Sr, Cr, V, Zn, Y, Ni and Ba. Some elements, such as Ba, Cd, Cu, La, Pb, Se, Sr, Th and Y, were enriched in the phosphogypsum. This enrichment may be attributed to an additional input associated to the sulfuric acid used for the phosphoric acid production. Furthermore, results from SEM-EDX demonstrated that toxic elements are not distributed homogeneously into phosphogypsum. Most of these elements are concentrated in particles <20 {mu}m of high porosity, and could be easily mobilized by leaching and/or erosion.

  13. Adaptation of Opossum Kidney Cells to Luminal Phosphate: Effects of Phosphonoformic Acid and Kinase Inhibitors

    Directory of Open Access Journals (Sweden)

    Linto Thomas

    2016-05-01

    Full Text Available Background/Aims: Renal reabsorption of inorganic phosphate (Pi is mediated by SLC34 and SLC20 Na+/Pi-cotransporters the abundance of which is under hormonal control. Extracellular Pi itself also regulates the expression of cotransporters and the concentration of Pi-regulating hormones, though the signaling pathways are largely unknown. Here, we explored the mechanisms that allow renal proximal cells to adapt to changes in the concentration of Pi. Methods: opossum kidney (OK cells, a model of proximal epithelia, were incubated with different concentrations of Pi in the absence/presence of phosphonoformic acid (PFA, a Pi-analogue and SLC34-inhibitor, and of inhibitors of kinases involved in hormonal control of Pi-homeostasis; cells cultured in normal media were treated with uncouplers of oxidative phosphorylation. Then, the intracellular concentration of ATP and/or the Pi-transport capacity of the cultures were analyzed. Results: luminal Pi regulates the Pi-transport and the intracellular ATP levels. Changes in ATP seem secondary to alterations in Pi-transport, rather than ATP acting as a signal. Adaptation of Pi-transport to high Pi was not mimicked by PFA. Transport adaptation was blocked by PFA but not by kinase inhibitors. Conclusions: in OK cells, adaptation of Pi-transport to luminal Pi does not depend on the same signaling pathways involved in hormonal regulation.

  14. Regulation of Amino Acid, Nucleotide, and Phosphate Metabolism in Saccharomyces cerevisiae

    Science.gov (United States)

    Ljungdahl, Per O.; Daignan-Fornier, Bertrand

    2012-01-01

    Ever since the beginning of biochemical analysis, yeast has been a pioneering model for studying the regulation of eukaryotic metabolism. During the last three decades, the combination of powerful yeast genetics and genome-wide approaches has led to a more integrated view of metabolic regulation. Multiple layers of regulation, from suprapathway control to individual gene responses, have been discovered. Constitutive and dedicated systems that are critical in sensing of the intra- and extracellular environment have been identified, and there is a growing awareness of their involvement in the highly regulated intracellular compartmentalization of proteins and metabolites. This review focuses on recent developments in the field of amino acid, nucleotide, and phosphate metabolism and provides illustrative examples of how yeast cells combine a variety of mechanisms to achieve coordinated regulation of multiple metabolic pathways. Importantly, common schemes have emerged, which reveal mechanisms conserved among various pathways, such as those involved in metabolite sensing and transcriptional regulation by noncoding RNAs or by metabolic intermediates. Thanks to the remarkable sophistication offered by the yeast experimental system, a picture of the intimate connections between the metabolomic and the transcriptome is becoming clear. PMID:22419079

  15. Phytic Acid and Inorganic Phosphate Composition in Soybean Lines with Independent IPK1 Mutations

    Directory of Open Access Journals (Sweden)

    Jennifer A. Vincent

    2015-03-01

    Full Text Available Soybean seeds contain a large amount of P, which is stored as phytic acid (PA. Phytic acid is indigestible by nonruminant livestock and considered an antinutritional factor in soybean meal. Several low PA soybean lines have been discovered, but many of these lines have either minor reductions in PA or inadequate germination and emergence. The reduced PA phenotype of soybean line Gm-lpa-ZC-2 was previously shown to be the result of a mutation in a gene encoding an inositol pentakisphosphate 2-kinase on chromosome 14 (14IPK1. While the 14IPK1 mutation was shown to have no impact on germination and emergence, the reduction in PA was modest (up to 50%. Our objective was to determine the effect on seed P partitioning for a novel mutation of an independent gene on chromosome six (06IPK1 on its own and in combination with mutant alleles of the 14IPK1. We developed soybean populations and conducted genotype and phenotype association analyses based on the genotype of the 06IPK1 and 14IPK1 genes and the seed P partitioning profile. The lines with both mutant genes had very low PA levels, moderate accumulation of inorganic phosphate (Pi, and accumulation of high amounts of P in lower inositols. The developed lines did not have significant reductions in germination or field emergence. In addition, characterization of the lower inositols produced in the mutant lines suggests that IPK1 is a polyphosphate kinase and provides some insight into the PA biosynthesis pathway in soybean seeds.

  16. Sequential incorporation of metallic cations (Cd2+ and Hg2+) and N-octylamine into titanium phosphate nanoparticles and their subsequent release in acid media.

    Science.gov (United States)

    Carrasco-Rodríguez, Javier; Martín-Yerga, Daniel; Garrido, Leoncio; Costa-García, Agustín; García Alonso, Francisco J

    2017-05-30

    Titanium phosphate nanoparticles, TPNP, consisting of a NaTi2(PO4)3 core and a shell of hydrogen phosphate and dihydrogen phosphate of titanium, undergo fast hydrolysis in water releasing phosphoric acid. This reaction is inhibited in the presence of metallic ions like Cd2+ or Hg2+, which are able to replace the protons of the shell acid phosphates. The amount of the adsorbed metallic cations could be regulated using counterions of different basicity. The resulting nanoparticles also incorporate NH2(CH2)7CH3 (N-octylamine) at room temperature forming N-octylammonium/phosphate ion pairs, but it was found that at higher cation concentration inside the nanoparticle, a lower amount of amine was adsorbed. The metallic cations and N-octylamine are released in acid media, but the starting material is not fully recovered.

  17. A study of organic acid production in contrasts between two phosphate solubilizing fungi: Penicillium oxalicum and Aspergillus niger

    Science.gov (United States)

    Li, Zhen; Bai, Tongshuo; Dai, Letian; Wang, Fuwei; Tao, Jinjin; Meng, Shiting; Hu, Yunxiao; Wang, Shimei; Hu, Shuijin

    2016-04-01

    Phosphate solubilizing fungi (PSF) have huge potentials in enhancing release of phosphorus from fertilizer. Two PSF (NJDL-03 and NJDL-12) were isolated and identified as Penicillium oxalicum and Aspergillus niger respectively in this study. The quantification and identification of organic acids were performed by HPLC. Total concentrations of organic acids secreted by NJDL-03 and NJDL-12 are ~4000 and ~10,000 mg/L with pH values of 3.6 and 2.4 respectively after five-days culture. Oxalic acid dominates acidity in the medium due to its high concentration and high acidity constant. The two fungi were also cultured for five days with the initial pH values of the medium varied from 6.5 to 1.5. The biomass reached the maximum when the initial pH values are 4.5 for NJDL-03 and 2.5 for NJDL-12. The organic acids for NJDL-12 reach the maximum at the initial pH = 5.5. However, the acids by NJDL-03 continue to decrease and proliferation of the fungus terminates at pH = 2.5. The citric acid production increases significantly for NJDL-12 at acidic environment, whereas formic and oxalic acids decrease sharply for both two fungi. This study shows that NJDL-12 has higher ability in acid production and has stronger adaptability to acidic environment than NJDL-03.

  18. Designable architectures on nanoparticle surfaces: zirconium phosphate nanoplatelets as a platform for tetravalent metal and phosphonic acid assemblies.

    Science.gov (United States)

    Mosby, Brian M; Goloby, Mark; Díaz, Agustín; Bakhmutov, Vladimir; Clearfield, Abraham

    2014-03-11

    Surface-functionalized zirconium phosphate (ZrP) nanoparticles were synthesized using a combination of ion exchange and self-assembly techniques. The surface of ZrP was used as a platform to deposit tetravalent metal ions by direct ion exchange with the protons of the surface phosphate groups. Subsequently, phosphonic acids were attached to the metal ion layer, effectively functionalizing the ZrP nanoparticles. Use of axially oriented bisphosphonic acids led to the ability to build layer-by-layer assemblies from the nanoparticle surface. Varying the metal ion and ligand used allowed designable architectures to be synthesized on the nanoparticle surface. X-ray powder diffraction, XPS, electron microprobe, solid-state NMR, FTIR, and TGA were used to characterize the synthesized materials.

  19. The synthetic xylulose-1 phosphate pathway increases production of glycolic acid from xylose-rich sugar mixtures

    OpenAIRE

    Trichez, Débora; Cam, Yvan; Spina, Lucie; François, Jean-Marie

    2016-01-01

    Background: Glycolic acid (GA) is a two-carbon hydroxyacid with applications in the cosmetic, textile, and medical industry. Microbial GA production from all sugars can be achieved by engineering the natural glyoxylate shunt. The synthetic (D)-xylulose-1 phosphate (X1P) pathway provides a complementary route to produce GA from (D)-xylose. The simultaneous operation of the X1P and glyoxylate pathways increases the theoretical GA yield from xylose by 20 %, which may strongly improve GA producti...

  20. Oxidation of clindamycin phosphate by chromium(VI in aqueous sulfuric acid medium—A kinetic and mechanistic study

    Directory of Open Access Journals (Sweden)

    Amar K. Durgannavar

    2015-12-01

    Full Text Available Kinetics and mechanism of oxidation of clindamycin phosphate by potassium dichromate in aqueous sulfuric acid medium is studied spectrophotometrically at 25°C at a constant ionic strength of 3.60 mol dm−3. The stoichiometry of the reaction is determined and it was found that one mole of clindamycin phosphate consumes two moles of chromium(VI (1:2. The oxidation products are characterized and confirmed by spectral studies such as IR, GC-MS and LC-MS. The reaction is first order each in chromium(VI and clindamycin phosphate concentrations. An increase in the sulfuric acid concentration causes an increase of the reaction rate. The order with respect to acid concentration is found to be 1.65. From the results of kinetic studies, reaction stoichiometry and product analysis a suitable free radical mechanism is proposed. Based on investigation of the reaction at different temperatures, computation of the activation parameters with respect to the slow step of the proposed mechanism was evaluated.

  1. Tumor acidity-activatable manganese phosphate nanoplatform for amplification of photodynamic cancer therapy and magnetic resonance imaging.

    Science.gov (United States)

    Hao, Yongwei; Zheng, Cuixia; Wang, Lei; Zhang, Jinjie; Niu, Xiuxiu; Song, Qingling; Feng, Qianhua; Zhao, Hongjuan; Li, Li; Zhang, Hongling; Zhang, Zhenzhong; Zhang, Yun

    2017-10-15

    Amorphous biodegradable metal phosphate nanomaterials are considered to possess great potential in cancer theranostic application due to their promise in providing ultra-sensitive pH-responsive therapeutic benefits and diagnostic functions simultaneously. Here we report the synthesis of photosensitising and acriflavine-carrying amorphous porous manganese phosphate (PMP) nanoparticles with ultra-sensitive pH-responsive degradability and their application for a photoactivable synergistic nanosystem that imparts reactive oxygen species (ROS) induced cytotoxicity in synchrony with hypoxia-inducible factor 1α/vascular endothelial growth factor (HIF1α/VEGF) inhibitor that suppresses tumor growth and treatment escape signalling pathway. Carboxymethyl dextran (CMD) is chemically anchored on the surface of porous manganese phosphate theranostic system through the pH-responsive boronate esters. Upon the stimulus of the tumor acid microenvironment, manganese phosphate disintegrates and releases Mn 2+ ions rapidly, which are responsible for the magnetic resonance imaging (MRI) effect. Meanwhile, the released photosensitizer chlorin e6 (Ce6) produces ROS under irradiation while acriflavine (ACF) inhibits the HIF-1α/VEGF pathway during the burst release of VEGF in tumour induced by photodynamic therapy (PDT), resulting in increased therapeutic efficacy. Considering the strong pH responsivity, MRI signal amplification and drug release profile, the PMP nanoparticles offer new prospects for tumor acidity-activatable theranostic application by amplifying the PDT through inhibiting the HIF-1α /VEGF pathway timely while enhancing the MRI effect. In this study, we report the synthesis of the tumor acidity-activatable amorphous porous manganese phosphate nanoparticles and their application for a photoactivable synergistic nanosystem that imparts reactive oxygen species (ROS) induced cytotoxicity in synchrony with hypoxia-inducible factor 1α/vascular endothelial growth factor (HIF-1

  2. Role of phosphate in the central metabolism of two lactic acid bacteria--a comparative systems biology approach.

    Science.gov (United States)

    Levering, Jennifer; Musters, Mark W J M; Bekker, Martijn; Bellomo, Domenico; Fiedler, Tomas; de Vos, Willem M; Hugenholtz, Jeroen; Kreikemeyer, Bernd; Kummer, Ursula; Teusink, Bas

    2012-04-01

    Lactic acid-producing bacteria survive in distinct environments, but show common metabolic characteristics. Here we studied the dynamic interactions of the central metabolism in Lactococcus lactis, extensively used as a starter culture in the dairy industry, and Streptococcus pyogenes, a human pathogen. Glucose-pulse experiments and enzymatic measurements were performed to parameterize kinetic models of glycolysis. Significant improvements were made to existing kinetic models for L. lactis, which subsequently accelerated the development of the first kinetic model of S. pyogenes glycolysis. The models revealed an important role for extracellular phosphate in the regulation of central metabolism and the efficient use of glucose. Thus, phosphate, which is rarely taken into account as an independent species in models of central metabolism, should be considered more thoroughly in the analysis of metabolic systems in the future. Insufficient phosphate supply can lead to a strong inhibition of glycolysis at high glucose concentrations in both species, but this was more severe in S. pyogenes. S. pyogenes is more efficient at converting glucose to ATP, showing a higher tendency towards heterofermentative energy metabolism than L. lactis. Our comparative systems biology approach revealed that the glycolysis of L. lactis and S. pyogenes have similar characteristics, but are adapted to their individual natural habitats with respect to phosphate regulation. © 2012 The Authors Journal compilation © 2012 FEBS.

  3. ESTIMATION OF HYDROLYSIS RATE CONSTANTS OF CARBOXYLIC ACID ESTER AND PHOSPHATE ESTER COMPOUNDS IN AQUEOUS SYSTEMS FROM MOLECULAR STRUCTURE BY SPARC

    Science.gov (United States)

    SPARC (SPARC Performs Automated Reasoning in Chemistry) chemical reactivity models were extended to calculate hydrolysis rate constants for carboxylic acid ester and phosphate ester compounds in aqueous non- aqueous and systems strictly from molecular structure. The energy diffe...

  4. Phosphate Stability in Diagenetic Fluids Constrains the Acidic Alteration Model for Lower Mt. Sharp Sedimentary Rocks in Gale Crater, Mars

    Science.gov (United States)

    Berger, J. A.; Schmidt, M. E.; Izawa, M. R. M.; Gellert, R.; Ming, D. W.; Rampe, E. B.; VanBommel, S. J.; McAdam, A. C.

    2016-01-01

    The Mars rover Curiosity has encountered silica-enriched bedrock (as strata and as veins and associated halos of alteration) in the largely basaltic Murray Fm. of Mt. Sharp in Gale Crater. Alpha Particle X-ray Spectrometer (APXS) investigations of the Murray Fm. revealed decreasing Mg, Ca, Mn, Fe, and Al, and higher S, as silica increased (Fig. 1). A positive correlation between SiO2 and TiO2 (up to 74.4 and 1.7 wt %, respectively) suggests that these two insoluble elements were retained while acidic fluids leached more soluble elements. Other evidence also supports a silica-retaining, acidic alteration model for the Murray Fm., including low trace element abundances consistent with leaching, and the presence of opaline silica and jarosite determined by CheMin. Phosphate stability is a key component of this model because PO4 3- is typically soluble in acidic water and is likely a mobile ion in diagenetic fluids (pH less than 5). However, the Murray rocks are not leached of P; they have variable P2O5 (Fig. 1) ranging from average Mars (0.9 wt%) up to the highest values in Gale Crater (2.5 wt%). Here we evaluate APXS measurements of Murray Fm. bedrock and veins with respect to phosphate stability in acidic fluids as a test of the acidic alteration model for the Lower Mt. Sharp rocks.

  5. Influence of triethyl phosphate on phosphatase activity in shooting range soil: Isolation of a zinc-resistant bacterium with an acid phosphatase.

    Science.gov (United States)

    Story, Sandra; Brigmon, Robin L

    2017-03-01

    Phosphatase-mediated hydrolysis of organic phosphate may be a viable means of stabilizing heavy metals via precipitation as a metal phosphate in bioremediation applications. We investigated the effect of triethyl phosphate (TEP) on soil microbial-phosphatase activity in a heavy-metal contaminated soil. Gaseous TEP has been used at subsurface sites for bioremediation of organic contaminants but not applied in heavy-metal contaminated areas. Little is known about how TEP affects microbial activity in soils and it is postulated that TEP can serve as a phosphate source in nutrient-poor groundwater and soil/sediments. Over a 3-week period, TEP amendment to microcosms containing heavy-metal contaminated soil resulted in increased activity of soil acid-phosphatase and repression of alkaline phosphatase, indicating a stimulatory effect on the microbial population. A soil-free enrichment of microorganisms adapted to heavy-metal and acidic conditions was derived from the TEP-amended soil microcosms using TEP as the sole phosphate source and the selected microbial consortium maintained a high acid-phosphatase activity with repression of alkaline phosphatase. Addition of 5mM zinc to soil-free microcosms had little effect on acid phosphatase but inhibited alkaline phosphatase. One bacterial member from the consortium, identified as Burkholderia cepacia sp., expressed an acid-phosphatase activity uninhibited by high concentrations of zinc and produced a soluble, indigo pigment under phosphate limitation. The pigment was produced in a phosphate-free medium and was not produced in the presence of TEP or phosphate ion, indicative of purple acid-phosphatase types that are pressed by bioavailable phosphate. These results demonstrate that TEP amendment was bioavailable and increased overall phosphatase activity in both soil and soil-free microcosms supporting the possibility of positive outcomes in bioremediation applications. Copyright © 2016. Published by Elsevier Inc.

  6. Photoactive layer-by-layer films of cellulose phosphate and titanium dioxide containing phosphotungstic acid

    Energy Technology Data Exchange (ETDEWEB)

    Ullah, Sajjad [Instituto de Química de São Carlos, Universidade de São Paulo, PO Box 780, São Carlos, São Paulo 13564-970 (Brazil); Acuña, José Javier Sáez [Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo Andre, Sao Paulo, 09210-170 (Brazil); Pasa, André Avelino [Surface and Thin Film Laboratory, Physics Department, Federal University of Santa Catarina, PO Box 476, Florianópolis, SC 88040-900 (Brazil); Bilmes, Sara A. [Universidad de Buenos Aires, Facultad Ciencias Exactas y Naturales, Instituto de Química Física de los Materiales, Medio Ambiente y Energía – INQUIMAE, Ciudad Universitaria, Pab. 2, Buenos Aires C1428EHA (Argentina); Vela, Maria Elena; Benitez, Guillermo [Laboratorio de Nanoscopías y Fisicoquímica de Superficies, Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), Universidad Nacional de La Plata – CONICET, diagonal 113 esquina 64. C.C.16.Suc.4, 1900 La Plata (Argentina); Rodrigues-Filho, Ubirajara Pereira, E-mail: uprf@iqsc.usp.br [Instituto de Química de São Carlos, Universidade de São Paulo, PO Box 780, São Carlos, São Paulo 13564-970 (Brazil)

    2013-07-15

    A versatile layer-by-layer (LbL) procedure for the preparation of highly dispersed, adherent and porous multilayer films of TiO{sub 2} nanoparticles (NPs) and phosphotungstic acid (HPW) on a variety of substrates at room temperature was developed based on the use of cellulose phosphate (CP) as an efficient and non-conventional polyelectrolyte. UV/vis absorption spectroscopy confirmed the linear and regular growth of the films with the number of immersion cycles and a strong adsorption ability of CP towards TiO{sub 2} NPs. FTIR spectroscopy showed that HPW binds to the surface of TiO{sub 2} through the oxygen atom at the corner of the Keggin structure. XPS results showed that the interaction between TiO{sub 2} and CP is through Ti–O–P linkage. A model is proposed for the TiO{sub 2}–HPW interaction based on XPS and FTIR results. FEG/SEM study of the surface morphology revealed a porous film structure with a homogenous distribution of the TiO{sub 2} NPs induced by CP. HRTEM studies showed that the resulting composite films consist of crystalline anatase and rutile phases and poly-nano-crystalline HPW with a semi-crystalline TiO{sub 2}–HPW interface. These CP/TiO{sub 2} and CP/TiO{sub 2}/HPW LbL films showed good photoactivity against both saturated and unsaturated species, for instance, stearic acid (SA), crystal violet (CV) and methylene blue (MB) under UV irradiation. The CP/HPW films formed on bacterial cellulose (BC) showed good photochromic response which is enhanced in presence of TiO{sub 2} due to an interfacial electron transfer from TiO{sub 2} to HPW. This simple and environmentally safe method can be used to form coatings on a variety of surfaces with photoactive TiO{sub 2} and TiO{sub 2}/HPW films.

  7. Crystallization of dicalcium phosphate dihydrate with presence of glutamic acid and arginine at 37 °C.

    Science.gov (United States)

    Li, Chengfeng; Ge, Xiaolu; Li, Guochang; Bai, Jiahai; Ding, Rui

    2014-08-01

    The formations of non-metabolic stones, bones and teeth were seriously related to the morphology, size and surface reactivity of dicalcium phosphate dihydrate (DCPD). Herein, a facile biomimetic mineralization method with presence of glutamic acid and arginine was employed to fabricate DCPD with well-defined morphology and adjustable crystallite size. In reaction solution containing more arginine, crystallization of DCPD occurred with faster rate of nucleation and higher density of stacked layers due to the generation of more OH(-) ions after hydrolysis of arginine at 37 °C. With addition of fluorescein or acetone, the consumption of OH(-) ions or desolvation reaction of Ca(2+) ions was modulated, which resulted in the fabrication of DCPD with adjustable crystallite sizes and densities of stacked layers. In comparison with fluorescein-loading DCPD, dicalcium phosphate anhydrate was prepared with enhanced photoluminescence properties due to the reduction of self-quenching effect and regular arrangement of encapsulated fluorescein molecules. With addition of more acetone, DCPD was prepared with smaller crystallite size via antisolvent crystallization. The simulated process with addition of amino acids under 37 °C would shed light on the dynamic process of biomineralization for calcium phosphate compounds. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Application of poly(aspartic acid-citric acid copolymer compound inhibitor as an effective and environmental agent against calcium phosphate in cooling water systems

    Directory of Open Access Journals (Sweden)

    Yu-ling Zhang

    2016-12-01

    Full Text Available Poly(aspartic acid-citric acid copolymer (PAC is a new product of poly(carboxylic acid scale inhibitor. The study aims to develop a “green” water treatment agent for calcium phosphate scale. The article compares the efficiency of three polymeric antiscalants, poly(aspartic acid-citric acid copolymer (PAC, polymaleic acid (HPMA and a compound inhibitor (PAC-HPMA, for calcium phosphate scale prevention under varying experimental conditions. Inhibitor concentration, calcium concentration, system pH, temperature and experimental time were varied to determine their influences on inhibitor performance by the static scale inhibition method. The copolymer (PAC was characterized by FTIR, 1H NMR and 13C NMR. The compound inhibitor was applied in the actual circulating cooling water system. An atomic force microscope (AFM, X-ray powder diffraction (XRD and a scale formation process analysis were used to explore the scale inhibition mechanism. The results showed that scale inhibition rates of PAC, HPMA and PAC-HPMA against Ca3(PO42 were, respectively, about 23%, 41.5% and 63% when the dosage was 8 mg/L in the experiment. The compound inhibitor showed the better inhibition performance than the above two kinds of monomers. Under the actual working conditions, the inhibition rate of compound inhibitor was close to 100% and completely met the actual application requirements of scale inhibitor in circulating cooling water systems. The main inhibition mechanism was the decomposition-chelation dispersion effect. The compound inhibitor can be used as an efficient “green” scale inhibitor for calcium phosphate.

  9. Zinc phosphate conversion coatings

    Science.gov (United States)

    Sugama, T.

    1997-02-18

    Zinc phosphate conversion coatings for producing metals which exhibit enhanced corrosion prevention characteristics are prepared by the addition of a transition-metal-compound promoter comprising a manganese, iron, cobalt, nickel, or copper compound and an electrolyte such as polyacrylic acid, polymethacrylic acid, polyitaconic acid and poly-L-glutamic acid to a phosphating solution. These coatings are further improved by the incorporation of Fe ions. Thermal treatment of zinc phosphate coatings to generate {alpha}-phase anhydrous zinc phosphate improves the corrosion prevention qualities of the resulting coated metal. 33 figs.

  10. Zinc phosphate conversion coatings

    Science.gov (United States)

    Sugama, Toshifumi

    1997-01-01

    Zinc phosphate conversion coatings for producing metals which exhibit enhanced corrosion prevention characteristics are prepared by the addition of a transition-metal-compound promoter comprising a manganese, iron, cobalt, nickel, or copper compound and an electrolyte such as polyacrylic acid, polymethacrylic acid, polyitaconic acid and poly-L-glutamic acid to a phosphating solution. These coatings are further improved by the incorporation of Fe ions. Thermal treatment of zinc phosphate coatings to generate .alpha.-phase anhydrous zinc phosphate improves the corrosion prevention qualities of the resulting coated metal.

  11. Cytotoxicity detection of poly(lactic-co-glycolic acid/tricalcium phosphate

    Directory of Open Access Journals (Sweden)

    Meng SUN

    2011-12-01

    Full Text Available Objective To detecte the cytotoxicity of the PLGA/TCP(poly(lactic-co-glycolic acid/Tricalcium phosphate composite that based on the precedent experiments conducted in Tsinghua University.Methods Compared with the PLGA scaffold material,observated the surface and interior structure of the PLGA/TCP scaffold material by SEM(scanning electron microscope,the surface and interior of PLGA/TCP scaffold material appeared to be homogeneous porous under SEM,with fairly even porosity distribution.The pore diameter was approximately 400μm.The interpenetrative micro-pores were scattered over bigger pores’ periphery with approximately circular contour and 3~5 μm in diameter.These pores were interpenetrative,the average factor of porosity was 89.6%.And which selected rat L929 cell strain,and detected the cytotoxicity of the PLGA/TCP composite in vitro by MTT method.Results The surface and interior of PLGA/TCP scaffold material appeared to be homogeneous porous under SEM,with fairly even porosity distribution.The pore diameter was approximately 400μm.The interpenetrative micro-pores were scattered over bigger pores’ periphery with approximately circular contour and 3~5 μm in diameter.These pores were interpenetrative,the average factor of porosity was 89.6%.On rat L929 cell strain,used MTT Method to detect the cytotoxicity of the composite PLGA/ TCP in vitro,the result showed that the cytotoxicity of the PLGA/TCP composite was level I,according to the criterion,it can be considered as non cytotoxic.Conclusion This research has proved that the PLGA/TCP compound scaffold material has a more homogeneous structure,with the vesicular interior and the structure of PLGA/TCP composite is similar to natural bone trabecula,PLGA/TCP is non cytotoxicity,which satisfy the basic requirement of biological material application and provides a good experimental foundation for repairing autologous bone defect in the near future.

  12. The effects of template rigidity and amino acid type on heterogeneous calcium-phosphate mineralization by langmuir films of amphiphilic and acidic β-sheet peptides.

    Science.gov (United States)

    Segman-Magidovich, Shlomit; Rapaport, Hanna

    2012-09-13

    Calcium-phosphate mineralization was monitored in systems composed of designed amphiphilic and acidic β-sheet-forming peptides, namely Pro-Phe-(Asp-Phe)(5)-Pro (PFD-5), Pro-Phe-(Glu-Phe)(5)-Pro (PFE-5) and Pro-Glu-(Phe-PSer)(4)-Phe-Glu-Pro (PPS). The three peptides differ solely in terms of their hydrophilic amino acids and therefore, serve as good model for assessment of the effect of the anionic amino acid type on mineralization within the context of the β-sheet structure. Monolayers of the peptides were deposited over simulated body solution (SBF(1.5)), and the effect of the adsorbing minerals over time was detected by Langmuir isotherm measurements, grazing incidence X-ray diffraction (GIXD) and Brewster angle microscopy (BAM). The results provide insight into mineralized film morphology and peptide lattice behavior during mineralization. The rigidity of the peptide template, along with the type of amino acid side chain, were found to significantly affect mineralization morphology and peptide structure. The results will contribute to a better understanding of calcium-phosphate mineralization in nature and in the context of biomaterials for applications in bone tissue regeneration.

  13. Efficient therapy for refractory Pompe disease by mannose 6-phosphate analogue grafting on acid α-glucosidase.

    Science.gov (United States)

    Basile, Ilaria; Da Silva, Afitz; El Cheikh, Khaled; Godefroy, Anastasia; Daurat, Morgane; Harmois, Alice; Perez, Marc; Caillaud, Catherine; Charbonné, Henry-Vincent; Pau, Bernard; Gary-Bobo, Magali; Morère, Alain; Garcia, Marcel; Maynadier, Marie

    2018-01-10

    Pompe disease is a rare disorder due to deficiency of the acid α-glucosidase (GAA) treated by enzyme replacement therapy. The present authorized treatment with rhGAA, the recombinant human enzyme, provides an important benefit in the infantile onset; however, the juvenile and adult forms of the disease corresponding to >80% of the patients are less responsive to this treatment. This resistance has been mainly attributed to an insufficiency of mannose 6-phosphate residues in rhGAA to address lysosomes through the cation-independent mannose 6-phosphate receptor (CI-M6PR). As yet, several attempts to improve the enzyme delivery by increasing the number of mannose 6-phosphate on the enzyme were poorly effective on the late onset form of the disease. Here, we show that chemical conjugation of a synthetic analogue of the mannose 6-phosphate, named AMFA, onto rhGAA improves the affinity for CI-M6PR and the uptake of the enzyme in fibroblasts and myoblasts of adult Pompe patients. More importantly, only the conjugated rhGAA-AMFA was effective in aged Pompe mice when compared to rhGAA. Weekly treatment with 5-20mg·kg-1 rhGAA-AMFA provided major improvements of the motor function and of the myofiber structure, whereas rhGAA was inactive. Finally, AMFA addition did not induce supplementary immune response to the enzyme. This modified enzyme, displaying a muscle recovery in aged Pompe mice that was never attained before, could be considered as a potential therapy for the late onset Pompe disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Phosphate recovery through struvite-family crystals precipitated in the presence of citric acid: mineralogical phase and morphology evaluation.

    Science.gov (United States)

    Perwitasari, D S; Edahwati, L; Sutiyono, S; Muryanto, S; Jamari, J; Bayuseno, A P

    2017-11-01

    Precipitation strategy of struvite-family crystals is presented in this paper to recover phosphate and potassium from a synthetic wastewater in the presence of citric acid at elevated temperature. The crystal-forming solutions were prepared from crystals of MgCl2 and NH4H2PO4 with a molar ratio of 1:1:1 for Mg(+2), [Formula: see text], and [Formula: see text], and the citric acid (C6H8O7) was prepared (1.00 and 20.00 ppm) from citric acid crystals. The Rietveld analysis of X-ray powder diffraction pattern confirmed a mixed product of struvite, struvite-(K), and newberyite crystallized at 30°C in the absence of citric acid. In the presence of citric acid at 30° and 40°C, an abundance of struvite and struvite-(K) were observed. A minute impurity of sylvite and potassium peroxide was unexpectedly found in certain precipitates. The crystal solids have irregular flake-shaped morphology, as shown by scanning electron microscopy micrograph. All parameters (citric acid, temperature, pH, Mg/P, and N/P) were deliberately arranged to control struvite-family crystals precipitation.

  15. Enhanced root growth in phosphate-starved Arabidopsis by stimulating de novo phospholipid biosynthesis through the overexpression of LYSOPHOSPHATIDIC ACID ACYLTRANSFERASE 2 (LPAT2).

    Science.gov (United States)

    Angkawijaya, Artik Elisa; Nguyen, Van Cam; Nakamura, Yuki

    2017-09-01

    Upon phosphate starvation, plants retard shoot growth but promote root development presumably to enhance phosphate assimilation from the ground. Membrane lipid remodelling is a metabolic adaptation that replaces membrane phospholipids by non-phosphorous galactolipids, thereby allowing plants to obtain scarce phosphate yet maintain the membrane structure. However, stoichiometry of this phospholipid-to-galactolipid conversion may not account for the massive demand of membrane lipids that enables active growth of roots under phosphate starvation, thereby suggesting the involvement of de novo phospholipid biosynthesis, which is not represented in the current model. We overexpressed an endoplasmic reticulum-localized lysophosphatidic acid acyltransferase, LPAT2, a key enzyme that catalyses the last step of de novo phospholipid biosynthesis. Two independent LPAT2 overexpression lines showed no visible phenotype under normal conditions but showed increased root length under phosphate starvation, with no effect on phosphate starvation response including marker gene expression, root hair development and anthocyanin accumulation. Accompanying membrane glycerolipid profiling of LPAT2-overexpressing plants revealed an increased content of major phospholipid classes and distinct responses to phosphate starvation between shoot and root. The findings propose a revised model of membrane lipid remodelling, in which de novo phospholipid biosynthesis mediated by LPAT2 contributes significantly to root development under phosphate starvation. © 2017 John Wiley & Sons Ltd.

  16. Effect of medium acidity on the thermodynamics and kinetics of the reaction of pyridoxal 5'-phosphate with isoniazid in an aqueous solution

    Science.gov (United States)

    Gamov, G. A.; Zavalishin, M. N.; Usacheva, T. R.; Sharnin, V. A.

    2017-05-01

    Thermodynamic characteristics of the formation of the Schiff base between isoniazid and pyridoxal 5'-phosphate in an aqueous solution at different pH values of a medium are determined by means of spectrophotometry and calorimetric titration. The process kinetics is studied spectrophotometrically, and the reaction rate constants for the formation of the imine at different acidities of a medium are determined. Biochemical aspects of the binding of pyridoxal 5'-phosphate into stable compounds are discussed.

  17. Effect of Mg2+ on acidic calcium phosphate phases grown by electrodeposition

    Science.gov (United States)

    Correia, Matheus Bento; Júnior, José Pedro Gualberto; Macedo, Michelle Cardinale S. S.; Resende, Cristiane Xavier; dos Santos, Euler Araujo

    2017-10-01

    In this work, the effect of Mg2+ ions on the electrodeposition of dicalcium phosphate dihydrate (DCPD), octacalcium phosphate (OCP) and calcium-deficient hydroxyapatite (CDHA) crystals on a commercially pure titanium (cp-Ti) substrate was evaluated. We demonstrated that Mg2+ ions could change the morphology of the coatings by inhibiting the growth rate of the OCP and CDHA crystals and diminishing the crystallite size of DCPD. The inhibition effect on OCP and CDHA was most likely due to a surface adsorption mechanism since no evidence of a doping process was observed using Rietveld refinement and electron diffraction analyses. Conversely, the presence of Mg2+ ions generated a favorable condition for the nucleation of a new Mg2+-rich DCPD crystal population, presenting smaller crystallite sizes.

  18. Investigating the use of coupling agents to improve the interfacial properties between a resorbable phosphate glass and polylactic acid matrix.

    Science.gov (United States)

    Hasan, Muhammad Sami; Ahmed, Ifty; Parsons, Andrew J; Rudd, Chris D; Walker, Gavin S; Scotchford, Colin A

    2013-09-01

    Eight different chemicals were investigated as potential candidate coupling agents for phosphate glass fibre reinforced polylactic acid composites. Evidence of reaction of the coupling agents with phosphate glass and their effect on surface wettability and glass degradation were studied along with their principle role of improving the interface between glass reinforcement and polymer matrix. It was found that, with an optimal amount of coupling agent on the surface of the glass/polymer, interfacial shear strength improved by a factor of 5. Evidence of covalent bonding between agent and glass was found for three of the coupling agents investigated, namely: 3-aminopropyltriethoxysilane; etidronic acid and hexamethylene diisocyanate. These three coupling agents also improved the interfacial shear strength and increased the hydrophobicity of the glass surface. It is expected that this would provide an improvement in the macroscopic properties of full-scale composites fabricated from the same materials which may also help to retain these properties for the desired length of time by retarding the breakdown of the fibre/matrix interface within these composites.

  19. Inhibitory effects of tributyl phosphate on algal growth, photosynthesis, and fatty acid synthesis in the marine diatom Phaeodactylum tricornutum.

    Science.gov (United States)

    Song, Hao; Fan, Xiaoji; Liu, Guangfu; Xu, Jiahui; Li, Xingxing; Tan, Yuzhu; Qian, Haifeng

    2016-12-01

    The widely used solvent extractant, tributyl phosphate (TBP), primarily used as a solvent for the conventional processing of nuclear fuel, has come under scrutiny recently due to concerns surrounding potential environmental contamination and toxicity. In this study, we found that, in Phaeodactylum tricornutum, administration of TBP severely inhibited algal cell growth by reducing photosynthetic efficiency and inducing oxidative stress. We further explored the effect of TBP by examining the gene expression of the photosynthetic electron transport chain and its contribution to reactive oxygen species (ROS) burst. Our data revealed that TBP affected both fatty acid content and profile by regulating the transcription of genes related to glycolysis, fatty acid biosynthesis, and β-oxidation. These results demonstrated that TBP did in fact trigger the synthesis of ROS, disrupting the subcellular membrane structure of this aquatic organism. Our study brings new insight into the fundamental mechanism of toxicity exerted by TBP on the marine alga P. tricornutum.

  20. Phosphate acquisition efficiency and phosphate starvation tolerance ...

    Indian Academy of Sciences (India)

    Phosphate availability is a major factor limiting tillering, grain filling vis-à-vis productivity of rice. Rice is often cultivated in soil like red and lateritic or acid, with low soluble phosphate content. To identify the best genotype suitable for these types of soils, P acquisition efficiency was estimated from 108 genotypes.

  1. Why Nature Chose Phosphates

    Science.gov (United States)

    Westheimer, F. H.

    1987-03-01

    Phosphate esters and anhydrides dominate the living world but are seldom used as intermediates by organic chemists. Phosphoric acid is specially adapted for its role in nucleic acids because it can link two nucleotides and still ionize; the resulting negative charge serves both to stabilize the diesters against hydrolysis and to retain the molecules within a lipid membrane. A similar explanation for stability and retention also holds for phosphates that are intermediary metabolites and for phosphates that serve as energy sources. Phosphates with multiple negative charges can react by way of the monomeric metaphosphate ion PO3{}- as an intermediate. No other residue appears to fulfill the multiple roles of phosphate in biochemistry. Stable, negatively charged phosphates react under catalysis by enzymes; organic chemists, who can only rarely use enzymatic catalysis for their reactions, need more highly reactive intermediates than phosphates.

  2. Separative recovery with lime of phosphate and fluoride from an acidic effluent containing H3PO4, HF and/or H2SiF6.

    Science.gov (United States)

    Gouider, Mbarka; Feki, Mongi; Sayadi, Sami

    2009-10-30

    Fluoride content and flow-rate of fertilizer plant wastewater from phosphoric acid and/or triple superphosphate (TSP) production lead to the discharge of several thousand tons of fluoride (F(-)) per year and even more for phosphate (PO4(3-)). Since sustainability is an important environmental concern, the removal methods should allow phosphorus and fluoride to be recycled as a sustainable products for use as raw materials either in agricultural or industrial applications. In the present work, separative recovery with lime of these two target species was investigated. A preliminary speciation study, carried out on the crude effluent, showed that two forms of fluoride: HF and H2SiF6 are present in a highly acidic medium (pH approximately 2). Evidence that fluoride is present under both free (HF) and combined (H2SiF6) forms, in the phosphate-containing effluent, was provided by comparing potentiometric titration curves of a crude wastewater sample and synthetic acid mixtures containing H3PO4, HF and H2SiF6. In a second step synthetic effluent containing mixtures of the following acids: HF, H2SiF6 and H3PO4, were treated with lime. The behaviour of these compounds under lime treatment was analysed. The data showed that fluoride has a beneficial effect on phosphate removal. Moreover, by acting on the precipitation pH, a "selective" recovery of fluoride and phosphate ions was possible either from phosphoric acid/hydrofluoric acid or phosphoric acid/hexafluorosilicic acid mixtures. Indeed, the first stage of the separative recovery, led to a fluoride removal efficiency of 97-98% from phosphoric acid/hydrofluoric acid mixture. It was of 93-95% from phosphoric acid/hexafluorosilicic acid mixture. During the second stage, the phosphate precipitation reached 99.8% from both acidic mixtures whereas it did not exceed 82% from a solution containing H3PO4 alone. The XRD and IR analyses showed that during lime treatment, a H2SiF6 hydrolysis occurred, instead of CaSiF6 solid

  3. Mechanical Behavior and Thermal Stability of Acid-Base Phosphate Cements and Composites Fabricated at Ambient Temperature

    Science.gov (United States)

    Colorado Lopera, Henry Alonso

    This dissertation presents the study of the mechanical behavior and thermal stability of acid-base phosphate cements (PCs) and composites fabricated at ambient temperature. These materials are also known as chemically bonded phosphate ceramics (CBPCs). Among other advantages of using PCs when compared with traditional cements are the better mechanical properties (compressive and flexural strength), lower density, ultra-fast (controllable) setting time, controllable pH, and an environmentally benign process. Several PCs based on wollastonite and calcium and alumino phosphates after thermal exposure up to 1000°C have been investigated. First, the thermo-mechanical and chemical stability of wollastonite-based PC (Wo-PC) exposed to temperatures up to 1000°C in air environment were studied. The effects of processing conditions on the curing and shrinkage of the wollastonite-based PC were studied. The chemical reactions and phase transformations during the fabrication and during the thermal exposure are analyzed in detail using scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermo-gravimetric analysis (TGA Then, the thermo-mechanical and chemical stability of glass, carbon and basalt fiber reinforced Wo-PC composites, were studied using SEM, XRD, TGA. The flexural strength and Weibull statistics were analyzed. A significant strength degradation in the composites were found after the thermal exposure at elevated temperatures due to the interdifusion and chemical reactions across the fibers and the matrix at temperatures over 600°C. To overcome this barrier, we have developed a new PC based on calcium and alumino-phosphates (Ca-Al PCs). The Ca-Al PCs were studied in detail using SEM, XRD, TGA, curing, shrinkage, Weibull statistics, and compression tests. Our study has confirmed that this new composite material is chemically and mechanically stable at temperatures up to 1000°C. Moreover, the compression strength increases after exposure to 1000

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

    Science.gov (United States)

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

    2016-02-01

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

  5. Phosphate Uptake by Phosphate-Starved Euglena

    Science.gov (United States)

    BLUM, J. J.

    1966-01-01

    Phosphate-deprived Euglena acquire the ability to rapidly in-corporate added phosphate and, also, synthesize an induced acid phosphatase localized in the pellicle. The phosphate uptake system is saturated at low concentrations of phosphate and is inhibited by dinitrophenol, by low temperature, by K+, Li+, and Na+ ions, and competitively by arsenate. The orthophosphate incorporated into the cell is rapidly converted into organic forms but enough remains unesterified to suggest that the uptake is an active transport process. The data do not rule out the possibility that the induced phosphatase is involved in the transport process. PMID:5924104

  6. A role for AMPK in the inhibition of glucose-6-phosphate dehydrogenase by polyunsaturated fatty acids

    Energy Technology Data Exchange (ETDEWEB)

    Kohan, Alison B.; Talukdar, Indrani; Walsh, Callee M. [Department of Biochemistry, West Virginia University, Morgantown, WV (United States); Salati, Lisa M., E-mail: lsalati@hsc.wvu.edu [Department of Biochemistry, West Virginia University, Morgantown, WV (United States)

    2009-10-09

    Both polyunsaturated fatty acids and AMPK promote energy partitioning away from energy consuming processes, such as fatty acid synthesis, towards energy generating processes, such as {beta}-oxidation. In this report, we demonstrate that arachidonic acid activates AMPK in primary rat hepatocytes, and that this effect is p38 MAPK-dependent. Activation of AMPK mimics the inhibition by arachidonic acid of the insulin-mediated induction of G6PD. Similar to intracellular signaling by arachidonic acid, AMPK decreases insulin signal transduction, increasing Ser{sup 307} phosphorylation of IRS-1 and a subsequent decrease in AKT phosphorylation. Overexpression of dominant-negative AMPK abolishes the effect of arachidonic acid on G6PD expression. These data suggest a role for AMPK in the inhibition of G6PD by polyunsaturated fatty acids.

  7. The oxygen isotope composition of phosphate released from phytic acid by the activity of wheat and Aspergillus niger phytase

    Science.gov (United States)

    von Sperber, C.; Tamburini, F.; Brunner, B.; Bernasconi, S. M.; Frossard, E.

    2015-07-01

    Phosphorus (P) is an essential nutrient for living organisms. Under P-limiting conditions plants and microorganisms can exude extracellular phosphatases that release inorganic phosphate (Pi) from organic phosphorus compounds (Porg). Phytic acid (myo-inositol hexakisphosphate, IP6) is an important form of Porg in many soils. The enzymatic hydrolysis of IP6 by phytase yields available Pi and less phosphorylated inositol derivates as products. The hydrolysis of organic P compounds by phosphatases leaves an isotopic imprint on the oxygen isotope composition (δ18O) of released Pi, which might be used to trace P in the environment. This study aims at determining the effect of phytase on the oxygen isotope composition of released Pi. For this purpose, enzymatic assays with histidine acid phytases from wheat and Aspergillus niger were prepared using IP6, adenosine 5'-monophosphate (AMP) and glycerophosphate (GPO4) as substrates. For a comparison to the δ18O of Pi released by other extracellular enzymes, enzymatic assays with acid phosphatases from potato and wheat germ with IP6 as a substrate were prepared. During the hydrolysis of IP6 by phytase, four of the six Pi were released, and one oxygen atom from water was incorporated into each Pi. This incorporation of oxygen from water into Pi was subject to an apparent inverse isotopic fractionation (ϵ ~ 6 to 10 ‰), which was similar to that imparted by acid phosphatase from potato during the hydrolysis of IP6 (ϵ ~ 7 ‰), where less than three Pi were released. The incorporation of oxygen from water into Pi during the hydrolysis of AMP and GPO4 by phytase yielded a normal isotopic fractionation (ϵ ~ -12 ‰), similar to values reported for acid phosphatases from potato and wheat germ. We attribute this similarity in ϵ to the same amino acid sequence motif (RHGXRXP) at the active site of these enzymes, which leads to similar reaction mechanisms. We suggest that the striking

  8. Bile Acid-Mediated Sphingosine-1-Phosphate Receptor 2 Signaling Promotes Neuroinflammation during Hepatic Encephalopathy in Mice

    Directory of Open Access Journals (Sweden)

    Matthew McMillin

    2017-07-01

    Full Text Available Hepatic encephalopathy (HE is a neuropsychiatric complication that occurs due to deteriorating hepatic function and this syndrome influences patient quality of life, clinical management strategies and survival. During acute liver failure, circulating bile acids increase due to a disruption of the enterohepatic circulation. We previously identified that bile acid-mediated signaling occurs in the brain during HE and contributes to cognitive impairment. However, the influences of bile acids and their downstream signaling pathways on HE-induced neuroinflammation have not been assessed. Conjugated bile acids, such as taurocholic acid (TCA, can activate sphingosine-1-phosphate receptor 2 (S1PR2, which has been shown to promote immune cell infiltration and inflammation in other models. The current study aimed to assess the role of bile-acid mediated S1PR2 signaling in neuroinflammation and disease progression during azoxymethane (AOM-induced HE in mice. Our findings demonstrate a temporal increase of bile acids in the cortex during AOM-induced HE and identified that cortical bile acids were elevated as an early event in this model. In order to classify the specific bile acids that were elevated during HE, a metabolic screen was performed and this assay identified that TCA was increased in the serum and cortex during AOM-induced HE. To reduce bile acid concentrations in the brain, mice were fed a diet supplemented with cholestyramine, which alleviated neuroinflammation by reducing proinflammatory cytokine expression in the cortex compared to the control diet-fed AOM-treated mice. S1PR2 was expressed primarily in neurons and TCA treatment increased chemokine ligand 2 mRNA expression in these cells. The infusion of JTE-013, a S1PR2 antagonist, into the lateral ventricle prior to AOM injection protected against neurological decline and reduced neuroinflammation compared to DMSO-infused AOM-treated mice. Together, this identifies that reducing bile acid

  9. Porous calcium phosphate-poly (lactic-co-glycolic) acid composite bone cement: A viable tunable drug delivery system.

    Science.gov (United States)

    Roy, Abhijit; Jhunjhunwala, Siddharth; Bayer, Emily; Fedorchak, Morgan; Little, Steve R; Kumta, Prashant N

    2016-02-01

    Calcium phosphate based cements (CPCs) are frequently used as bone void fillers for non-load bearing segmental bone defects due to their clinically relevant handling characteristics and ability to promote natural bone growth. Macroporous CPC scaffolds with interconnected pores are preferred for their ability to degrade faster and enable accelerated bone regeneration. Herein, a composite CPC scaffold is developed using newly developed resorbable calcium phosphate cement (ReCaPP) formulation containing degradable microspheres of bio-compatible poly (lactic-co-glycolic acid) (PLGA) serving as porogen. The present study is aimed at characterizing the effect of in-vitro degradation of PLGA microspheres on the physical, chemical and structural characteristics of the composite cements. The porosity measurements results reveal the formation of highly interconnected macroporous scaffolds after degradation of PLGA microspheres. The in-vitro characterizations also suggest that the degradation by products of PLGA reduces the pH of the local environment thereby increasing the dissolution rate of the cement. In addition, the in-vitro vancomycin release from the composite CPC scaffold suggests that the drug association with the composite scaffolds can be tuned to achieve control release kinetics. Further, the study demonstrates control release lasting for longer than 10weeks from the composite cements in which vancomycin is encapsulated in PLGA microspheres. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Analysis of residual trifluoroacetic acid in a phosphate-buffered saline matrix by ion chromatography with suppressed conductivity detection.

    Science.gov (United States)

    Fernando, P N; McLean, M A; Egwu, I N; deGuzman, E; Weyker, C

    2001-06-22

    As part of the formulation of a cell-based pharmaceutical product, cells were harvested from mice and incubated in a cocktail containing cell culture media and high levels of trifluoroacetic acid (TFA). The cells were washed with a phosphate-buffered saline solution to remove residual cell culture media and other reagents before the cells were infused back into the mice from which they originated. Because of the potentially toxic nature of the TFA, the cells were washed multiple times and the final wash was monitored for residual TFA in order to demonstrate the efficient removal of the reagent before the cell product could be reintroduced into the test animal. This report describes the method that was developed incorporating anion-exchange chromatography with suppressed conductivity detection for the analysis of residual TFA (down to 50 ng/ml) in the presence of high concentrations of phosphate and chloride interferences. The ultimate sensitivity of the method was improved by selectively removing halide anions using a silver cartridge before sample analysis. The method proved to be rugged and reproducible enough to be validated and used to monitor residual TFA levels in cell washes in support of an acute toxicological study. Results demonstrating the method's sensitivity, selectivity, precision and linearity were reported.

  11. Sorption of U(VI) on goethite: Effects of pH, ionic strength, phosphate, carbonate and fulvic acid

    Energy Technology Data Exchange (ETDEWEB)

    Guo Zhijun [Radiochemistry Lab, School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China)], E-mail: guozhj@lzu.edu.cn; Li Yan; Wu Wangsuo [Radiochemistry Lab, School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China)

    2009-06-15

    U(VI) sorption on goethite was investigated as functions of pH, solid-to-liquid ratio (m/V), ionic strength and U(VI) concentration by a batch experimental method. Effects of phosphate, carbonate and fulvic acid (FA) on U(VI) sorption were examined. It was found that the sorption of U(VI) increases from 0% to 100% over the pH range of 2.5-4.5 and keeps constant in the high pH range. The sorption of U(VI) on goethite is insensitive to ionic strength. Different surface complexes in the framework of double-layer model were examined for fitting the sorption of U(VI) on goethite. A model with two mononuclear inner-sphere surface complexes, {identical_to}SOUO{sub 2}{sup +} and {identical_to}SOUO{sub 2}OH, was found capable of reproducing the pH sorption edges, the sorption isotherms and the sorption data with variable m/V in this study. The proposed model can also interpret the pH sorption edge collected at P{sub CO{sub 2}}=10{sup -3.58}atm without considering any ternary surface complexes of carbonate. Moreover, it was found that the presence of phosphate at relatively high concentration (6x10{sup -4} mol/L) promotes U(VI) sorption. The presence of FA of 20 mg/L has little effect on the sorption of U(VI) on goethite.

  12. In vitro lead bioaccessibility and phosphate leaching as affected by surface application of phosphoric acid in lead-contaminated soil.

    Science.gov (United States)

    Yang, J; Mosby, D E; Casteel, S W; Blanchar, R W

    2002-11-01

    Phosphate treatment of lead-contaminated soil may be a cost-effective remedial alternative for in situ stabilizing soil Pb and reducing Pb toxicology to human. The leaching behaviors of the P added to soil surface and the effect on subsurface Pb bioaccessibility must be addressed for this remedial technology to be acceptable. A smelter-contaminated soil containing an average of 2,670 mg Pb kg(-1), collected from the Jasper County Superfund Site located in Jasper County, Missouri, was surface treated with 10 g P kg(-1) as phosphoric acid (H(3)PO(4)). Following a simulated column leaching and 90-day treatment of field plots, respectively, bioaccessible Pb, P, and pH in soil profile were measured. Surface treatment using H(3)PO(4) effectively stabilized soil Pb and reduced leachable Pb and the bioaccessibility. Phosphate leached into deeper profile significantly lowered bioaccessible Pb in subsurface. Reduction of Pb bioaccessibility increased as a linear function of increasing soil P. Although surface H(3)PO(4) treatment resulted in an enhanced leaching of added P and may increase potential risk of surface and groundwater pollution, the P leaching under field conditions is very limited. Lime addition following the treatment may reduce the leachability of added P and further immobilize soil Pb.

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

    Science.gov (United States)

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

    2012-06-01

    The use of degradable composite materials in orthopedics remains a field of intense research due to their ability to support new bone formation and degrade in a controlled manner, broadening their use for orthopedic applications. Poly (lactide-co-glycolide) acid (PLGA), a degradable biopolymer, is now a popular material for different orthopedic applications and is proposed for use in tissue engineering scaffolds either alone or combined with bioactive ceramics. Interference screws composed of calcium phosphates and PLGA are readily available in the market. However, some reports highlight problems of screw migration or aseptic cyst formation following screw degradation. In order to understand these phenomena and to help to improve implant formulation, we have evaluated the effects of PLGA degradation products: lactic acid and glycolic acid on human osteoblasts in vitro. Cell proliferation, differentiation, and matrix mineralization, important for bone healing were studied. It was found that the toxicity of polymer degradation products under buffering conditions was limited to high concentrations. However, non-toxic concentrations led to a decrease in cell proliferation, rapid cell differentiation, and mineralization failure. Calcium, whilst stimulating cell proliferation was not able to overcome the negative effects of high concentrations of lactic and glycolic acids on osteoblasts. These effects help to explain recently reported clinical failures of calcium phosphate/PLGA composites, but further in vitro analyses are needed to mimic the dynamic situation which occurs in the body by, for example, culture of osteoblasts with materials that have been pre-degraded to different extents and thus be able to relate these findings to the degradation studies that have been performed previously. Copyright © 2011 Orthopaedic Research Society.

  14. Natural and pyrogenic humic acids at goethite and natural oxide surfaces interacting with phosphate

    NARCIS (Netherlands)

    Hiemstra, T.; Mia, S.; Duhaut, P.B.; Molleman, B.

    2013-01-01

    Fulvic and humic acids have a large variability in binding to metal (hydr) oxide surfaces and interact differently with oxyanions, as examined here experimentally. Pyrogenic humic acid has been included in our study since it will be released to the environment in the case of large-scale application

  15. Synthesization and characterization of poly(lactic-co-glycolic acid) / calcium phosphate bone cement from crab shells

    Science.gov (United States)

    Hanan, M. R. Abdul; Daud, N. M.; Ismail, L. H.; Saidin, S.

    2017-05-01

    An injectable calcium phosphate (CaP) bone cement has been widely used for musculoskeletal and bone disorder due to its biocompatible and osteoconductive properties. In this study, CaP was successfully synthesized from crab shells by a wet chemical route. Poly(lactic-co-glycolic acid) (PLGA) microspheres which have been produced through a double emulsion technique were incorporated into the CaP mixture for the purpose of bone cement solidification. The ratio of both compounds, CaP and PLGA, were set at 8:2. The CaP and PLGA/CaP bone cement were analyzed by ATR-FTIR, FESEM-EDX and contact angle analyses. The bone cement was composed of CaP and PLGA where the micro-powders of CaP were agglomerated on the PLGA microspheres. Addition of the PLGA has increased the hydrophilicity of the bone cement which will be beneficial for materials degradation and bone integration.

  16. Metabolic influence of lead on polyhydroxyalkanoates (PHA) production and phosphate uptake in activated sludge fed with glucose or acetic acid as carbon source.

    Science.gov (United States)

    You, Sheng-Jie; Tsai, Yung-Pin; Cho, Bo-Chuan; Chou, Yi-Hsiu

    2011-09-01

    Sludge in a sequential batch reactor (SBR) system was used to investigate the effect of lead toxicity on metabolisms of polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) communities fed with acetic acid or glucose as their sole carbon source, respectively. Results showed that the effect of lead on substrate utilization of both PAOs and GAOs was insignificant. However, lead substantially inhibited both of phosphate release and uptake of PAOs. In high concentration of acetic acid trials, an abnormal aerobic phosphate release was observed instead of phosphate uptake and the release rate increased with increasing lead concentration. Results also showed that PAOs could normally synthesize polyhydroxybutyrate (PHB) in the anaerobic phase even though lead concentration was 40 mg L(-1). However, they could not aerobically utilize PHB normally in the presence of lead. On the other hand, GAOs could not normally metabolize polyhydroxyvalerate (PHV) in both the anaerobic and aerobic phases. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Improvement of phosphate solubilization and Medicago plant yield by an indole-3-acetic acid-overproducing strain of Sinorhizobium meliloti.

    Science.gov (United States)

    Bianco, Carmen; Defez, Roberto

    2010-07-01

    Nitrogen (N) and phosphorus (P) are the most limiting factors for plant growth. Some microorganisms improve the uptake and availability of N and P, minimizing chemical fertilizer dependence. It has been published that the RD64 strain, a Sinorhizobium meliloti 1021 strain engineered to overproduce indole-3-acetic acid (IAA), showed improved nitrogen fixation ability compared to the wild-type 1021 strain. Here, we present data showing that RD64 is also highly effective in mobilizing P from insoluble sources, such as phosphate rock (PR). Under P-limiting conditions, the higher level of P-mobilizing activity of RD64 than of the 1021 wild-type strain is connected with the upregulation of genes coding for the high-affinity P transport system, the induction of acid phosphatase activity, and the increased secretion into the growth medium of malic, succinic, and fumaric acids. Medicago truncatula plants nodulated by RD64 (Mt-RD64), when grown under P-deficient conditions, released larger amounts of another P-solubilizing organic acid, 2-hydroxyglutaric acid, than plants nodulated by the wild-type strain (Mt-1021). It has already been shown that Mt-RD64 plants exhibited higher levels of dry-weight production than Mt-1021 plants. Here, we also report that P-starved Mt-RD64 plants show significant increases in both shoot and root fresh weights when compared to P-starved Mt-1021 plants. We discuss how, in a Rhizobium-legume model system, a balanced interplay of different factors linked to bacterial IAA overproduction rather than IAA production per se stimulates plant growth under stressful environmental conditions and, in particular, under P starvation.

  18. Pseudomonas fluorescens ATCC 13525 containing an artificial oxalate operon and Vitreoscilla hemoglobin secretes oxalic acid and solubilizes rock phosphate in acidic alfisols.

    Directory of Open Access Journals (Sweden)

    Kavita Yadav

    Full Text Available Oxalate secretion was achieved in Pseudomonas fluorescens ATCC 13525 by incorporation of genes encoding Aspergillus niger oxaloacetate acetyl hydrolase (oah, Fomitopsis plaustris oxalate transporter (FpOAR and Vitreoscilla hemoglobin (vgb in various combinations. Pf (pKCN2 transformant containing oah alone accumulated 19 mM oxalic acid intracellularly but secreted 1.2 mM. However, in the presence of an artificial oxalate operon containing oah and FpOAR genes in plasmid pKCN4, Pf (pKCN4 secreted 13.6 mM oxalate in the medium while 3.6 mM remained inside. This transformant solubilized 509 μM of phosphorus from rock phosphate in alfisol which is 4.5 fold higher than the Pf (pKCN2 transformant. Genomic integrants of P. fluorescens (Pf int1 and Pf int2 containing artificial oxalate operon (plac-FpOAR-oah and artificial oxalate gene cluster (plac-FpOAR-oah, vgb, egfp secreted 4.8 mM and 5.4 mM oxalic acid, released 329 μM and 351 μM P, respectively, in alfisol. The integrants showed enhanced root colonization, improved growth and increased P content of Vigna radiata plants. This study demonstrates oxalic acid secretion in P. fluorescens by incorporation of an artificial operon constituted of genes for oxalate synthesis and transport, which imparts mineral phosphate solubilizing ability to the organism leading to enhanced growth and P content of V. radiata in alfisol soil.

  19. Study on synthetic methods of trialkyl phosphate oxide and its extraction behavior of some acids

    Energy Technology Data Exchange (ETDEWEB)

    Yu, M.J.; Su, Y.F.

    1987-01-01

    Trioctyl phosphine oxide (TOPO) is useful for the extraction of many inorganic and organic compounds. A mixed trialkyl phosphine oxide (TRPO) is similar in property to TOPO. The total number of carbon atoms per molecule of TRPO ranges from 15 to 27. Three methods for synthesizing TRPO are described in this paper. When TRPO is synthesized from an alcohol mixture it is significantly cheaper than a single pure alcohol as required for the production of TOPO; tedious purification steps are eliminated. TRPO is a brown liquid which is very slightly soluble in water. Toxicological measurements of LD50, AMES test, hereditary and accumulative toxicity show that TRPO is safe for use in the extraction of some pharmaceutical and biochemical compounds. Examinations of IR and NMR show that the complex interaction of P=O bond of TRPO with extracted substances is the same as that of TOPO. The distribution coefficients of phosphoric acid, citric acid, malic acid, oxalic acid, and tartaric acid with TRPO are reported. The extraction of these acids is believed to proceed by neutral-complex mechanism.

  20. The bone-regenerative properties of Emdogain adsorbed onto poly(D,L-lactic-coglycolic acid)/calcium phosphate composites in an ectopic and an orthotopic rat model.

    NARCIS (Netherlands)

    Plachokova, A.S.; Dolder, J. van den; Jansen, J.A.

    2008-01-01

    BACKGROUND AND OBJECTIVE: The aim of this study was to evaluate the bone-regenerative properties of Emdogain in osseous and nonosseous sites. MATERIAL AND METHODS: For the orthotopic study, unloaded poly(D,L-lactic-coglycolic acid)/calcium phosphate implants, and poly(D,L-lactic-coglycolic

  1. Second trimester amniotic fluid glucose, uric acid, phosphate, potassium, and sodium concentrations in relation to maternal pre-pregnancy BMI and birth weight centiles.

    Science.gov (United States)

    Fotiou, Maria; Michaelidou, Alexandra Maria; Athanasiadis, Apostolos P; Menexes, Georgios; Symeonidou, Maria; Koulourida, Vasiliki; Ganidou, Maria; Theodoridis, Theodoros D; Tarlatzis, Basil C

    2015-05-01

    To study the evolution profile of amniotic fluid (AF) glucose, uric acid, phosphate, potassium, and sodium, in the second trimester of pregnancy, and explore the possible relations between the concentration of these components and maternal, as well as neonatal characteristics. AF of 52 pregnant women was analyzed using an automatic multichannel analyzer. Maternal age, pre-pregnancy Body Mass Index (BMI), inter-pregnancy intervals, and smoking status were derived from questionnaires. Information on pregnancy and delivery was collected from medical records. Uric acid increased (r = 0.423, p uric acid concentration (r = 0.460, p uric acid and phosphate levels were significantly related to birth weight centiles (R(2)( )= 0.345, p uric acid concentration, and (c) in appropriate for gestational age infants, AF phosphate and uric acid levels may serve as potential biomarkers of birth weight centiles. Further studies on AF composition may help to unravel the biochemical pathways underlying fetal development and could offer insight on the potential impact of maternal nutritional management on fetal growth regulation.

  2. Altered expression of sphingosine kinase 1 and sphingosine-1-phosphate receptor 1 in mouse hippocampus after kainic acid treatment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Hoon; Jeon, Byeong Tak; Jeong, Eun Ae [Department of Anatomy and Neurobiology, Institute of Health Sciences, Medical Research Center for Neural Dysfunction, Biomedical Center (BK21), Gyeongsang National University School of Medicine, Jinju, Gyeongnam 660-751 (Korea, Republic of); Kim, Joon Soo; Cho, Yong Woon [Department of Neurosurgery, Masan Samsung Hospital, Sungkyunkwan University School of Medicine, Masan, Gyeongnam 630-723 (Korea, Republic of); Kim, Hyun Joon; Kang, Sang Soo; Cho, Gyeong Jae; Choi, Wan Sung [Department of Anatomy and Neurobiology, Institute of Health Sciences, Medical Research Center for Neural Dysfunction, Biomedical Center (BK21), Gyeongsang National University School of Medicine, Jinju, Gyeongnam 660-751 (Korea, Republic of); Roh, Gu Seob, E-mail: anaroh@gnu.ac.kr [Department of Anatomy and Neurobiology, Institute of Health Sciences, Medical Research Center for Neural Dysfunction, Biomedical Center (BK21), Gyeongsang National University School of Medicine, Jinju, Gyeongnam 660-751 (Korea, Republic of)

    2010-03-12

    Kainic acid (KA) induces hippocampal cell death and astrocyte proliferation. There are reports that sphingosine kinase (SPHK)1 and sphingosine-1- phosphate (S1P) receptor 1 (S1P{sub 1}) signaling axis controls astrocyte proliferation. Here we examined the temporal changes of SPHK1/S1P{sub 1} in mouse hippocampus during KA-induced hippocampal cell death. Mice were killed at 2, 6, 24, or 48 h after KA (30 mg/kg) injection. There was an increase in Fluoro-Jade B-positive cells in the hippocampus of KA-treated mice with temporal changes of glial fibrillary acidic protein (GFAP) expression. The lowest level of SPHK1 protein expression was found 2 h after KA treatment. Six hours after KA treatment, the expression of SPHK1 and S1P{sub 1} proteins steadily increased in the hippocampus. In immunohistochemical analysis, SPHK1 and S1P{sub 1} are more immunoreactive in astrocytes within the hippocampus of KA-treated mice than in hippocampus of control mice. These results indicate that SPHK1/S1P{sub 1} signaling axis may play an important role in astrocytes proliferation during KA-induced excitotoxicity.

  3. Improvement of Glyphosate Resistance through Concurrent Mutations in Three Amino Acids of the Ochrobactrum 5-Enopyruvylshikimate-3-Phosphate Synthase ▿

    Science.gov (United States)

    Tian, Yong-Sheng; Xu, Jing; Xiong, Ai-Sheng; Zhao, Wei; Fu, Xiao-Yan; Peng, Ri-He; Yao, Quan-Hong

    2011-01-01

    A mutant of 5-enopyruvylshikimate-3-phosphate synthase from Ochrobactrum anthropi was identified after four rounds of DNA shuffling and screening. Its ability to restore the growth of the mutant ER2799 cell on an M9 minimal medium containing 300 mM glyphosate led to its identification. The mutant had mutations in seven amino acids: E145G, N163H, N267S, P318R, M377V, M425T, and P438L. Among these mutations, N267S, P318R, and M425T have never been previously reported as important residues for glyphosate resistance. However, in the present study they were found by site-directed mutagenesis to collectively contribute to the improvement of glyphosate tolerance. Kinetic analyses of these three mutants demonstrated that the effectiveness of these three individual amino acid alterations on glyphosate tolerance was in the order P318R > M425T > N267S. The results of the kinetic analyses combined with a three-dimensional structure modeling of the location of P318R and M425T demonstrate that the lower hemisphere's upper surface is possibly another important region for glyphosate resistance. Furthermore, the transgenic Arabidopsis was obtained to confirm the potential of the mutant in developing glyphosate-resistant crops. PMID:21948846

  4. Metal-phosphate binders

    Science.gov (United States)

    Howe, Beth Ann [Lewistown, IL; Chaps-Cabrera, Jesus Guadalupe [Coahuila, MX

    2009-05-12

    A metal-phosphate binder is provided. The binder may include an aqueous phosphoric acid solution, a metal-cation donor including a metal other than aluminum, an aluminum-cation donor, and a non-carbohydrate electron donor.

  5. Regulation of the Formation of Acid Phosphatases by Inorganic Phosphate in Aspergillus ficuum1

    Science.gov (United States)

    Shieh, T. R.; Wodzinski, R. J.; Ware, J. H.

    1969-01-01

    Two types of extracellular acid phosphatases are synthesized by Aspergillus ficuum NRRL 3135: a nonspecific orthophosphoric monoester phosphohydrolase (EC 3.1.3.2) with an optimum pH of 2.0, and an enzyme with restricted specificity, a mesoinositol-hexaphosphate phosphohydrolase (EC 3.1.3.8; phytase) with an optimum pH of 5.5. Although the pH 5.5 enzyme is termed a phytase, both enzymes hydrolyze phytin. Synthesis of the enzymes is repressed by high orthophosphate concentrations in the fermentation medium. The highest total level for each enzyme is synthesized in low orthophosphate medium. In high orthophosphate medium, more pH 5.5 enzyme is produced than pH 2.0 enzyme. In low orthophosphate medium, more pH 5.5 enzyme is produced than pH 2.0 enzyme during the early stages of growth, but the reverse occurs after 5 days. The enzymes are differentiated by heat denaturation at acid and alkaline pH levels. They are separated into two distinct fractions on Sephadex G-100 followed by carboxymethylcellulose column chromatography. This indicates that the two enzymes are structurally different. The Km for both enzymes is 1.25 mm when calcium phytate is the substrate. Orthophosphate competitively inhibits the pH 2.0 (Ki = 1.1 × 10−2m) but not the pH 5.5 phosphatase. Neither enzyme is denatured by 50% (w/v) urea or inhibited by 0.01 m tartrate. Thus, they differ from human prostatic phosphatase. PMID:4311867

  6. Regulation of the formation of acid phosphatases by inorganic phosphate in Aspergillus ficuum.

    Science.gov (United States)

    Shieh, T R; Wodzinski, R J; Ware, J H

    1969-12-01

    Two types of extracellular acid phosphatases are synthesized by Aspergillus ficuum NRRL 3135: a nonspecific orthophosphoric monoester phosphohydrolase (EC 3.1.3.2) with an optimum pH of 2.0, and an enzyme with restricted specificity, a mesoinositol-hexaphosphate phosphohydrolase (EC 3.1.3.8; phytase) with an optimum pH of 5.5. Although the pH 5.5 enzyme is termed a phytase, both enzymes hydrolyze phytin. Synthesis of the enzymes is repressed by high orthophosphate concentrations in the fermentation medium. The highest total level for each enzyme is synthesized in low orthophosphate medium. In high orthophosphate medium, more pH 5.5 enzyme is produced than pH 2.0 enzyme. In low orthophosphate medium, more pH 5.5 enzyme is produced than pH 2.0 enzyme during the early stages of growth, but the reverse occurs after 5 days. The enzymes are differentiated by heat denaturation at acid and alkaline pH levels. They are separated into two distinct fractions on Sephadex G-100 followed by carboxymethylcellulose column chromatography. This indicates that the two enzymes are structurally different. The K(m) for both enzymes is 1.25 mm when calcium phytate is the substrate. Orthophosphate competitively inhibits the pH 2.0 (K(i) = 1.1 x 10(-2)m) but not the pH 5.5 phosphatase. Neither enzyme is denatured by 50% (w/v) urea or inhibited by 0.01 m tartrate. Thus, they differ from human prostatic phosphatase.

  7. Lysophosphatidic acid activates peroxisome proliferator activated receptor-γ in CHO cells that over-express glycerol 3-phosphate acyltransferase-1.

    Directory of Open Access Journals (Sweden)

    Cliona M Stapleton

    Full Text Available Lysophosphatidic acid (LPA is an agonist for peroxisome proliferator activated receptor-γ (PPARγ. Although glycerol-3-phosphate acyltransferase-1 (GPAT1 esterifies glycerol-3-phosphate to form LPA, an intermediate in the de novo synthesis of glycerolipids, it has been assumed that LPA synthesized by this route does not have a signaling role. The availability of Chinese Hamster Ovary (CHO cells that stably overexpress GPAT1, allowed us to analyze PPARγ activation in the presence of LPA produced as an intracellular intermediate. LPA levels in CHO-GPAT1 cells were 6-fold higher than in wild-type CHO cells, and the mRNA abundance of CD36, a PPARγ target, was 2-fold higher. Transactivation assays showed that PPARγ activity was higher in the cells that overexpressed GPAT1. PPARγ activity was enhanced further in CHO-GPAT1 cells treated with the PPARγ ligand troglitazone. Extracellular LPA, phosphatidic acid (PA or a membrane-permeable diacylglycerol had no effect, showing that PPARγ had been activated by LPA generated intracellularly. Transient transfection of a vector expressing 1-acylglycerol-3-phosphate acyltransferase-2, which converts endogenous LPA to PA, markedly reduced PPARγ activity, as did over-expressing diacylglycerol kinase, which converts DAG to PA, indicating that PA could be a potent inhibitor of PPARγ. These data suggest that LPA synthesized via the glycerol-3-phosphate pathway can activate PPARγ and that intermediates of de novo glycerolipid synthesis regulate gene expression.

  8. In Vivo Predictive Dissolution: Comparing the Effect of Bicarbonate and Phosphate Buffer on the Dissolution of Weak Acids and Weak Bases.

    Science.gov (United States)

    Krieg, Brian J; Taghavi, Seyed Mohammad; Amidon, Gordon L; Amidon, Gregory E

    2015-09-01

    Bicarbonate is the main buffer in the small intestine and it is well known that buffer properties such as pKa can affect the dissolution rate of ionizable drugs. However, bicarbonate buffer is complicated to work with experimentally. Finding a suitable substitute for bicarbonate buffer may provide a way to perform more physiologically relevant dissolution tests. The dissolution of weak acid and weak base drugs was conducted in bicarbonate and phosphate buffer using rotating disk dissolution methodology. Experimental results were compared with the predicted results using the film model approach of (Mooney K, Mintun M, Himmelstein K, Stella V. 1981. J Pharm Sci 70(1):22-32) based on equilibrium assumptions as well as a model accounting for the slow hydration reaction, CO2 + H2 O → H2 CO3 . Assuming carbonic acid is irreversible in the dehydration direction: CO2 + H2 O ← H2 CO3 , the transport analysis can accurately predict rotating disk dissolution of weak acid and weak base drugs in bicarbonate buffer. The predictions show that matching the dissolution of weak acid and weak base drugs in phosphate and bicarbonate buffer is possible. The phosphate buffer concentration necessary to match physiologically relevant bicarbonate buffer [e.g., 10.5 mM (HCO3 (-) ), pH = 6.5] is typically in the range of 1-25 mM and is very dependent upon drug solubility and pKa . © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

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

    Energy Technology Data Exchange (ETDEWEB)

    Xu Sanzhong; Lin Xiangjin [The First Affiliated Hospital, College of Medicine of Zhejiang University, Hangzhou 310003 (China); Yang Xianyan; Chen Xiaoyi; Gao Changyou; Gou Zhongru [Zhejiang-California International NanoSystems Institute, Zhejiang University, Hangzhou 310029 (China); Zhang Lei; Yang Guojing, E-mail: zhrgou@zju.edu.cn [Rui' an People' s Hospital and the 3rd Hospital Affiliated to Wenzhou Medical College, Rui' an 325200 (China)

    2011-06-15

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

  10. Oxidation of clindamycin phosphate by cerium(IV in perchloric acid medium – A kinetic and mechanistic approach

    Directory of Open Access Journals (Sweden)

    Seema S. Badi

    2017-02-01

    Full Text Available Methyl 7-chloro-6,7,8-trideoxy-6-[(2S,4R-1-methyl-4-propylpyrrolidine-2-carboxamido]-1-thio-1-threo-D-galactooctapyranoside monohydrochloride, commonly called clindamycin phosphate(CYN-P used largely as an antibiotic for the treatment of serious infections caused by susceptible Gram-positive bacteria and an-aerobic bacteria was oxidized by using Ceric ammonium sulphate (Ce(IV in perchloric acid medium. Progress of the reaction was followed by measuring the decrease in absorbance of ceric ammonium sulphate at 360 nm. The reaction was found to be first order each in [CYN-P] and [Ce(IV]. Order in [HClO4] was calculated as 0.8. The reactive species of Ce(IV appears to be H3Ce(SO44−. Stoichiometry of the reaction was found to be 2:1 of [Ce(IV]:[CYN-P]. Initially added product did not alter the rate of reaction. A free radical mechanism was proposed, and rate law was derived and verified. The activation parameters, ΔH≠, ΔS≠, ΔG≠ and log A were found to be 54.7 kJ mol−1, −117 J K−1 mol−1, 103 kJ mol−1 and 7, respectively.

  11. Development of an Injectable Calcium Phosphate/Hyaluronic Acid Microparticles System for Platelet Lysate Sustained Delivery Aiming Bone Regeneration.

    Science.gov (United States)

    Babo, Pedro S; Santo, Vítor E; Gomes, Manuela E; Reis, Rui L

    2016-11-01

    Despite the biocompatibility and osteoinductive properties of calcium phosphate (CaP) cements their low biodegradability hampers full bone regeneration. Herein the incorporation of CaP cement with hyaluronic acid (HAc) microparticles loaded with platelet lysate (PL) to improve the degradability and biological performance of the cements is proposed. Cement formulations incorporating increasing weight ratios of either empty HAc microparticles or microparticles loaded with PL (10 and 20 wt%) are developed as well as cements directly incorporating PL. The direct incorporation of PL improves the mechanical properties of the plain cement, reaching values similar to native bone. Morphological analysis shows homogeneous particle distribution and high interconnectivity between the HAc microparticles. The cements incorporating PL (with or without the HAc microparticles) present a sustained release of PL proteins for up to 8 d. The sustained release of PL modulates the expression of osteogenic markers in seeded human adipose tissue derived stem cells, thus suggesting the stimulatory role of this hybrid system toward osteogenic commitment and bone regeneration applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Extraction of thorium(IV) from aqueous nitric acid solutions by Tri-iso-Amyl phosphate (TAP)

    Energy Technology Data Exchange (ETDEWEB)

    Jaiswal, S.; Rupainwar, D.C. (Banaras Hindu Univ., Varanasi (India). Inst. of Tech.)

    1984-03-01

    The indigenously prepared solvent tri-iso-amyl phosphate (TAP) obtained from fusel oil, a byproduct of Indian alcohol industry, has been successfully utilized to extract thorium(IV) from its aqueous nitrate solutions. Maximum extraction of the metal has been found under two different conditions; at 5.5 M (H/sub 3/O/sup +/), 94% of Th(IV) can be extracted by using 55% TAP in carbon tetrachloride (vol/vol) while at a lower acidity viz. pH range of 4.06-4.5 already 18% TAP in CCl/sub 4/ extracts thorium(IV) almost quantitatively. The effect of parameters such as (H/sub 3/O/sup +/), (Th(IV)) and diluent for TAP were investigated and discussed. In the above cases the species which is eventually extracted into the organic phase is found to be disolvated and trisolvated at pH 4.06 and (H/sub 3/O/sup +/)=5.5 M, resp. The mechanism of the extractions under two different conditions is suggested. 13 refs.

  13. Enhanced removal of humic acid from aqueous solution by novel stabilized nano-amorphous calcium phosphate: Behaviors and mechanisms

    Science.gov (United States)

    Jiang, Ling; Li, Yiming; Shao, Yi; Zhang, Yong; Han, Ruiming; Li, Shiyin; Wei, Wei

    2018-01-01

    Stabilized nano-amorphous calcium phosphate (nACP) was prepared using polyethylene glycol as stabilizer to obtain a nanosized amorphous adsorbent. The produced nACP was evaluated by using XRD, FTIR, SEM and X-ray photoelectron spectroscopy (XPS). The sedimentation test demonstrated that nACP exhibited better stability than crystallized hydroxyapatite. The adsorption efficiency of the nACP material for aqueous humic acid (HA) was evaluated from the point of view of medium pH, adsorption time, temperature, and ionic strength, as well as the presences of metal ions. The results of the study showed very good adsorption performance towards aqueous HA. The Sips modeling results revealed that the stabilized nACP adsorbent had a considerably high adsorption capacity (248.3 mg/g) for HA at 298 K. The adsorption data fitted well into pseudo-second order and Elovich kinetic models. XPS analyses indicated that HA retention on nACP material might be due to the surface complexation reaction between oxygen-containing group and calcium of HA and nACP, respectively. Moreover, the HA adsorption capacity of nACP could still keep more than 86% after four adsorption-desorption cycles. By taking into account all results it was concluded that the nACP adsorbent leveraged its stability in combination with its high uptake capacity to offer a great promise for HA adsorption from water.

  14. Cytocompatibility and Mechanical Properties of Short Phosphate Glass Fibre Reinforced Polylactic Acid (PLA) Composites: Effect of Coupling Agent Mediated Interface

    Science.gov (United States)

    Hasan, Muhammad Sami; Ahmed, Ifty; Parsons, Andrew; Walker, Gavin; Scotchford, Colin

    2012-01-01

    In this study three chemical agents Amino-propyl-triethoxy-silane (APS), sorbitol ended PLA oligomer (SPLA) and Hexamethylene diisocyanate (HDI) were identified to be used as coupling agents to react with the phosphate glass fibre (PGF) reinforcement and the polylactic acid (PLA) polymer matrix of the composite. Composites were prepared with short chopped strand fibres (l = 20 mm, ϕ = 20 µm) in a random arrangement within PLA matrix. Improved, initial composite flexural strength (~20 MPa) was observed for APS treated fibres, which was suggested to be due to enhanced bonding between the fibres and polymer matrix. Both APS and HDI treated fibres were suggested to be covalently linked with the PLA matrix. The hydrophobicity induced by these coupling agents (HDI, APS) helped to resist hydrolysis of the interface and thus retained their mechanical properties for an extended period of time as compared to non-treated control. Approximately 70% of initial strength and 65% of initial modulus was retained by HDI treated fibre composites in contrast to the control, where only ~50% of strength and modulus was retained after 28 days of immersion in PBS at 37 °C. All coupling agent treated and control composites demonstrated good cytocompatibility which was comparable to the tissue culture polystyrene (TCP) control, supporting the use of these materials as coupling agent’s within medical implant devices. PMID:24955744

  15. Comparison and preparation of multilayered polylactic acid fabric strengthen calcium phosphate-based bone substitutes for orthopedic applications.

    Science.gov (United States)

    Chen, Wen-Cheng; Ko, Chia-Ling; Yang, Jia-Kai; Wu, Hui-Yu; Lin, Jia-Horng

    2016-03-01

    An attempt to maintain the three-dimensional space into restorative sites through the conveniently pack porous fillers are general used strategy. Advancement in the manufacturing protective shells in the scaffolds, which would be filled with brittle ceramic grafts for the development of highly connective pores provides the approach to solve crack problem for generating the tissues. Therefore, multilayered braided and alkalized poly(lactic acid) (PLA) composites with calcium phosphate bone cement (CPC) were synthesized and compared. The PLA/CPC composites were divided into various groups according to a series of heat-treatment temperatures (100-190 °C) and periods (1-3 h) and then characterized. The effects of 24-h immersion on the strength decay resistance of the samples were compared. Results showed that the residual oil capped on the surfaces of alkalized PLA braid was removed, and the structure was unaltered. However, the reduced tensile stress of alkalized PLA braids was due to ester-group formation by hydrolysis. Mechanical test results of PLA/CPC composites showed that the strength significantly increased after heat treatment, except when the heating temperature was higher than the PLA melting point at approximately 160-170 °C. The degree of PLA after recrystallization became higher than that of unheated composites, thereby leading to reduced strength and toughness of the specimen. Braiding fibers of biodegradable PLA reinforced and toughened the structure particularly of the extra-brittle material of thin-sheet CPC after implantation.

  16. Efficacy of cosmetic formulations containing dispersion of liposome with magnesium ascorbyl phosphate, alpha-lipoic acid and kinetin.

    Science.gov (United States)

    Campos, Patrícia Maria Berardo Gonçalves Maia; de Camargo Júnior, Flávio Bueno; de Andrade, Jirrah Pedro; Gaspar, Lorena Rigo

    2012-01-01

    The present study aimed to evaluate the photoprotective effects of cosmetic formulations containing a dispersion of liposome with magnesium ascorbyl phosphate (MAP), alpha-lipoic acid (ALA) and kinetin, as well as their effects on the hydration and viscoelastic skin properties. The photoprotection was determined in vitro (antioxidant activity) and in vivo on UV-irradiated hairless mouse skin. The hydration effects were performed with the application of the formulations under study on the forearm of human volunteers and skin conditions were analyzed before and after a single application and daily applications during 4 weeks in terms of transepidermal water loss (TEWL), skin moisture and viscoelastic properties. The raw material under study possessed free-radical scavenging activity and the formulation with it protected hairless mouse skin barrier function against UV damage. After 4 weeks of application on human skin, the formulation under study enhanced stratum corneum skin moisture and also showed hydration effects in deeper layers of the skin. Thus, it can be concluded that the cosmetic formulation containing a dispersion of liposome with MAP, ALA and kinetin under study showed photoprotective effects in skin barrier function as well as pronounced hydration effects on human skin, which suggests that this dispersion has potential antiaging effects. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

  17. Mechanical properties' improvement of a tricalcium phosphate scaffold with poly-l-lactic acid in selective laser sintering.

    Science.gov (United States)

    Liu, Defu; Zhuang, Jingyu; Shuai, Cijun; Peng, Shuping

    2013-06-01

    To improve the mechanical properties of a scaffold fabricated via selective laser sintering (SLS), a small amount (0.5-3 wt%) of poly-l-lactic acid (PLLA) is added to the β-tricalcium phosphate (β-TCP) powder. The fracture toughness of the scaffold prepared with the mixture powder containing 1 wt% PLLA increases by 18.18% and the compressive strength increases by 4.45% compared to the scaffold prepared from the β-TCP powder. The strengthening and toughening is related to the enhancement of β-TCP sintering characteristics via introducing a transient liquid phase in SLS. Moreover, the microcracks caused by the volume expansion due to the β-α phase transformation of TCP are reduced because of the PLLA inhibition function on the phase transformation. However, PLLA additive above 1 wt% would lead to a PLLA residue which will decrease the mechanical properties. The experimental results show that PLLA is an effective sintering aid to improve the mechanical properties of a TCP scaffold.

  18. 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.

  19. Biomedical nanocomposites of poly(lactic acid) and calcium phosphate hybridized with modified carbon nanotubes for hard tissue implants.

    Science.gov (United States)

    Lee, Hae-Hyoung; Sang Shin, Ueon; Lee, Jae-Ho; Kim, Hae-Won

    2011-08-01

    Degradable polymer-based materials are attractive in orthopedics and dentistry as an alternative to metallic implants for use as bone fixatives. Herein, a degradable polymer poly(lactic acid) (PLA) was combined with novel hybrid nanopowder of carbon nanotubes (CNTs)-calcium phosphate (CP) for this application. In particular, CNTs-CP hybrid nanopowders (0.1 and 0.25% CNTs) were prepared from the solution of ionically modified CNTs (mCNTs), which was specifically synthesized to be well-dispersed and thus to effectively adsorb onto the CP nanoparticles. The mCNTs-CP hybrid nanopowders were then mixed with PLA (up to 50%) to produce mCNTs-CP-PLA nanocomposites. The mechanical tensile strength of the nanocomposites was significantly improved by the addition of mCNTs-CP hybrid nanopowders. Moreover, nanocomposites containing low concentration of mCNTs (0.1%) showed significantly stimulated biological responses including cell proliferation and osteoblastic differentiation in terms of gene and protein expressions. Based on this study, the addition of novel mCNT-CP hybrid nanopowders to PLA biopolymer may be considered a new material choice for developing hard tissue implants. Copyright © 2011 Wiley Periodicals, Inc.

  20. A combination of biphasic calcium phosphate scaffold with hyaluronic acid-gelatin hydrogel as a new tool for bone regeneration.

    Science.gov (United States)

    Nguyen, Thuy Ba Linh; Lee, Byong-Taek

    2014-07-01

    A novel bone substitute was fabricated to enhance bone healing by combining ceramic and polymer materials. In this study, Hyaluronic acid (HyA)-Gelatin (Gel) hydrogel was loaded into a biphasic calcium phosphate (BCP) ceramic, and the resulting scaffold, with unique micro- and macroporous orientation, was evaluated for bone regeneration applications. The fabricated scaffold showed high interconnected porosity, with an average compressive strength of 2.8±0.15 MPa, which is usually recommended for cancellous bone substitution. In vitro cytocompatibility studies were conducted using bone marrow mesenchymal stem cells. The HyA-Gel-loaded BCP scaffold resulted in a significant increase in cell proliferation at 3 (p<0.05) and 7 days (p<0.001) and high alkaline phosphatase activities at 14 and 21 days. Furthermore, the in vivo studies showed that the implanted HyA-Gel-loaded BCP scaffold begins to degrade within 3 months after implantation. Histological sections also confirmed a rapid new bone formation and a high rate of collagen mineralization. A bone matrix formation was confirmed by positive immunohistochemistry staining of osteopontin, osteocalcin, and collagen type I. In vivo expression of extracellular matrix proteins demonstrated that this novel bone substitute holds great promise for use in stimulating new bone regeneration.

  1. Coating of ß-tricalcium phosphate scaffolds-a comparison between graphene oxide and poly-lactic-co-glycolic acid.

    Science.gov (United States)

    Ardjomandi, N; Henrich, A; Huth, J; Klein, C; Schweizer, E; Scheideler, L; Rupp, F; Reinert, S; Alexander, D

    2015-08-04

    Bone regeneration in critical size defects is a major challenge in oral and maxillofacial surgery, and the gold standard for bone reconstruction still requires the use of autologous tissue. To overcome the need for a second intervention and to minimize morbidity, the development of new biomaterials with osteoinductive features is the focus of current research. As a scaffolding material, ß-tricalcium phosphate (ß-TCP) is suitable for bone regeneration purposes, although it does not carry any functional groups for the covalent immobilization of molecules. The aim of the present study was to establish effective coating variants for ß-TCP constructs to enable the biofunctionalization of anorganic blocks with different osteogenic molecules in future studies. We established working protocols for thin surface coatings consisting of polylactic-co-glycolic acid (PLGA) and graphene oxide (GO) by varying parameters. Surface properties such as the angularity and topography of the developed scaffolds were analyzed. To examine biological functionality, the adhesion and proliferation behavior of jaw periosteal cells (JPCs) were tested on the coated constructs. Our results suggest that PLGA is the superior material for surface coating of ß-TCP matrices, leading to higher JPC proliferation rates and providing a more suitable basis for further biofunctionalization in the field of bone tissue engineering.

  2. Co-extraction and co-stripping of U(VI) and Pu(IV) using tri-iso-amyl phosphate and tri-n-butyl phosphate in n-dodecane from nitric acid media under high loading conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sreenivasulu, Balija; Suresh, Ammath; Sivaraman, Nagarajan; Rao, P.R. Vasudeva [Indira Gandhi Centre for Atomic Research, Kalpakkam (India). Chemistry Group

    2016-08-01

    The extraction of Pu(IV) using 1.1 M solution of tri-iso-amyl phosphate (TiAP)/n-dodecane (DD) from plutonium nitrate solutions in nitric acid media was examined as a function of equilibrium aqueous phase metal ion concentration and equilibrium aqueous phase acidity at 303 K. The nitric acid concentration in the organic phase was measured as a function of equilibrium organic phase plutonium concentration. The co-extraction of U(VI) and Pu(IV) was studied using 1.1 M TiAP/DD system as a function of their equilibrium aqueous phase metal ion concentration and compared with 1.1 M tri-n-butyl phosphate (TBP)/n-DD system under identical conditions. Co-extraction and co-stripping of U(VI) and Pu(IV) were studied using 1.1 M TiAP/DD and 1.1 M TBP/DD systems in cross current mode to evaluate the number of stages required for the extraction and stripping of heavy metal ions (uranium and plutonium). The extraction and stripping efficiencies were calculated for both the systems. The saturation limit of the organic phase was also established in these studies.

  3. Combined delivery of bone morphogenetic protein-2 and insulin-like growth factor-1 from nano-poly (γ-glutamic acid)/β-tricalcium phosphate-based calcium phosphate cement and its effect on bone regeneration in vitro.

    Science.gov (United States)

    Shu, Xiulin; Feng, Jin; Feng, Jing; Huang, Xiaomo; Li, Liangqiu; Shi, Qingshan

    2017-11-01

    In this study, nano-doped calcium phosphate cement delivery systems (poly (γ-glutamic acid)/β-tricalcium phosphate/calcium phosphate ceramics and nano (γ-glutamic acid)/β-tricalcium phosphate/calcium phosphate ceramic) were fabricated, and low doses (10 µg/g) of two growth factors, insulin-like growth factor-1 and bone morphogenetic protein-2, were encapsulated then sequentially released. We characterized the delivery systems using Fourier transform infrared spectroscopy and X-ray diffraction and measured washout resistance and compressive strength, and thus optimized the most appropriate proportioning of delivery systems for the two growth factors. One of the growth factors was absorbed by the nano-poly (γ-glutamic acid)/β-tricalcium phosphate, which was then mixed into the calcium phosphate ceramic solid phase to create a new solid phase calcium phosphate ceramic. Nano-poly (γ-glutamic acid)/β-tricalcium phosphate/calcium phosphate ceramic carriers were then prepared by blending the new calcium phosphate ceramic solid phase powder with a solution of the remaining growth factor. The effects of different release patterns (studying sequential behavior) of insulin-like growth factor-1 and bone morphogenetic protein-2 on osteogenic proliferation and differentiation of the MC3t3-E1 mouse osteoblast cell were investigated. This combinational delivery system provided a controlled release of the two growth factors, in which nano-doping significantly affected their release kinetics. The incorporation of dual growth factors could potentially stimulate bone healing and promoting bone ingrowth processes at a low dose.

  4. SINTESIS PATI SAGU IKATAN SILANG FOSFAT BERDERAJAT SUBSTITUSI FOSFAT TINGGI DALAM SUASANA ASAM [Synthesis of Cross-Linked Sago Starch Phosphate with the Highest Degree of Substitution of Phosphate Under Acidic Condition

    Directory of Open Access Journals (Sweden)

    Jorion Romengga*

    2011-12-01

    Full Text Available Cross-linked sago starch phosphate (SgP with high phosphorus contents was successfully synthesized by reacting sago with a mixture of primary and secondary sodium phosphates under acidic condition. The experimental variables investigated include pH, temperature, reaction time, and mixture rate. The physicochemical properties evaluated were moisture, swelling power, water binding capacity, transmittance (%T and percent amylose (%Am, while the pasting properties examined were pasting time, pasting temperature, viscosity at peak, final, and setback. The granule structure was observed by scanning electron microscope and X-ray diffraction. The results showed that the maximum degree of phosphate substitution was obtained at pH of 6.50, 40°C, 20 minutes of reaction time and 300 rpm of mixing rate. The physicochemical (%T and %Am and pasting (viscosity at peak, final, and setback properties of SgP were significantly different (P<0.01 from Sg. Structure of SgP was characterized by FT-IR and the results indicated a new absorption peak at 2362.87 cm-1 which was characterized as the phospho-diester (RO-PO3-R’ stretching vibration. In the fingerprint area, there were two new absorption peaks at 1242.05 and 989.79 cm-1 which were characterized as the P=O and C-O-P vibration, respectively. Sago granules were substantially altered after cross-linking.

  5. Quantification of three chlorinated dialkyl phosphates, diphenyl phosphate, 2,3,4,5-tetrabromobenzoic acid, and four other organophosphates in human urine by solid phase extraction-high performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Jayatilaka, Nayana K; Restrepo, Paula; Williams, LaTasha; Ospina, Maria; Valentin-Blasini, Liza; Calafat, Antonia M

    2017-02-01

    Polybrominated diphenyl ethers (PBDEs), produced as flame retardants worldwide, have been phased-out in many countries, and chlorinated and non-chlorinated organophosphates and non-PBDE brominated formulations (e.g., Firemaster 550 (FM550)) have entered the consumers' market. Recent studies show that components of organophosphate esters and FM550 are frequently detected in many products common to human environments. Therefore, urinary metabolites of these compounds can be used as human exposure biomarkers. We developed a method to quantify nine compounds in 0.4 mL urine: diphenyl phosphate (DPhP), bis(1,3-dichloro-2-propyl) phosphate (BDCPP), bis-(1-chloro-2-propyl) phosphate, bis-2-chloroethyl phosphate, di-p-cresylphosphate, di-o-cresylphosphate (DoCP), di-n-butyl phosphate, dibenzyl phosphate (DBzP), and 2,3,4,5-tetrabromobenzoic acid. The method relies on an enzymatic hydrolysis of urinary conjugates of the target analytes, automated off-line solid phase extraction, reversed phase high performance liquid chromatography separation, and isotope dilution-electrospray ionization tandem mass spectrometry detection. The method is high-throughput (96 samples/day) with detection limits ranging from 0.05 to 0.16 ng mL(-1). Spiked recoveries were 90-113 %, and interday imprecision was 2-8 %. We assessed the suitability of the method by analyzing urine samples collected from a convenience sample of adults (n = 76) and from a group of firefighters (n = 146). DPhP (median, 0.89; range, 0.26-5.6 ng mL(-1)) and BDCPP (median, 0.69; range, 0.31-6.8 ng mL(-1)) were detected in all of the non-occupationally exposed adult samples and all of the firefighter samples (DPhP [median, 2.9; range, 0.24-28 ng mL(-1)], BDCPP [median, 3.4; range, 0.30-44 ng mL(-1)]); DBzP and DoCP were not detected in any samples.

  6. Effect of phosphate-based glass fibre surface properties on thermally produced poly(lactic acid) matrix composites.

    Science.gov (United States)

    Mohammadi, Maziar Shah; Ahmed, Ifty; Muja, Naser; Rudd, Christopher D; Bureau, Martin N; Nazhat, Showan N

    2011-12-01

    Incorporation of soluble bioactive glass fibres into biodegradable polymers is an interesting approach for bone repair and regeneration. However, the glass composition and its surface properties significantly affect the nature of the fibre-matrix interface and composite properties. Herein, the effect of Si and Fe on the surface properties of calcium containing phosphate based glasses (PGs) in the system (50P(2)O(5)-40CaO-(10-x)SiO(2)-xFe(2)O(3), where x = 0, 5 and 10 mol.%) were investigated. Contact angle measurements revealed a higher surface energy, and surface polarity as well as increased hydrophilicity for Si doped PG which may account for the presence of surface hydroxyl groups. Two PG formulations, 50P(2)O(5)-40CaO-10Fe(2)O(3) (Fe10) and 50P(2)O(5)-40CaO-5Fe(2)O(3)-5SiO(2) (Fe5Si5), were melt drawn into fibres and randomly incorporated into poly(lactic acid) (PLA) produced by melt processing. The ageing in deionised water (DW), mechanical property changes in phosphate buffered saline (PBS) and cytocompatibility properties of these composites were investigated. In contrast to Fe10 and as a consequence of the higher surface energy and polarity of Fe5Si5, its incorporation into PLA led to increased inorganic/organic interaction indicated by a reduction in the carbonyl group of the matrix. PLA chain scission was confirmed by a greater reduction in its molecular weight in PLA-Fe5Si5 composites. In DW, the dissolution rate of PLA-Fe5Si5 was significantly higher than that of PLA-Fe10. Dissolution of the glass fibres resulted in the formation of channels within the matrix. Initial flexural strength was significantly increased through PGF incorporation. After PBS ageing, the reduction in mechanical properties was greater for PLA-Fe5Si5 compared to PLA-Fe10. MC3T3-E1 preosteoblasts seeded onto PG discs, PLA and PLA-PGF composites were evaluated for up to 7 days indicating that the materials were generally cytocompatible. In addition, cell alignment along the PGF

  7. Diglycolic acid modified zirconium phosphate and studies on the extraction of Am(III) and Eu(III) from dilute nitric acid medium

    Energy Technology Data Exchange (ETDEWEB)

    Selvan, B. Robert; Suneesh, A.S.; Venkatesan, K.A.; Antony, M.P. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India). Fuel Chemistry Division; Dasthaiah, K.; Gardas, R.L. [Indian Institute of Technology - Madras, Chennai (India). Dept. of Chemistry

    2017-06-01

    Diglycolic acid modified zirconium phosphate (ZrP-DGA) was prepared and studied for the extraction of Am(III) and Eu(III) from dilute nitric acid medium. The distribution coefficient (K{sub d}, mL.g{sup -1}) of Am(III) and Eu(III) was measured as a function of time, pH and concentration of Eu(III) ion etc. The K{sub d} of Am(III) and Eu(III) increased with increase of pH, reached a maximum value of distribution coefficient at pH 1.5 - 2, followed by decrease in K{sub d} values. Rapid extraction of Am(III) and Eu(III) in ZrP-DGA was observed followed by the establishment of equilibrium occurred in 100 min. Kinetics of extraction was fitted in to pseudo second order rate equation. The amount of Eu(III) loaded in ZrP-DGA increased with increase in the concentration of Eu(III) ion in aqueous phase and the isotherm was fitted in to Langmuir and Freundlich adsorption models. The extraction of Am(III) in ZrP-DGA was higher as compared to Eu(III) and the interference of Eu(III) on the extraction of Am(III) was studied. The distribution coefficient of some lanthanides in ZrP-DGA was measured and the K{sub d} of lanthanides increased across the lanthanide series. The extracted trivalent metal ions were recovered in three contacts of loaded ZrP-DGA with 0.5 M nitric acid.

  8. Evaluation of commonly used methods for the analysis of acid-soluble phosphate in internationally traded inorganic fertilizers.

    Science.gov (United States)

    Hall, William L; Siegel, Sanford

    2014-01-01

    Several methodologies are used throughout the world to determine phosphate concentration (measured as PO4 and expressed as % P2O5) in fertilizers. Concentrated phosphate materials, including diammonium phosphate (DAP) and monoammonium phosphate (MAP), are traded in large volumes (millions of metric tons) internationally. The International Fertilizer Association (IFA) identified a need to assess the methods currently being used to measure the phosphate content for suitability (scope), accuracy, and repeatability. Even small discrepancies in the expressed P2O5 content can have a major financial impact on buyers and sellers as contracts are settled and import regulations are imposed. The IFA's Technical Committee selected a working group to address issues dealing with harmonization of fertilizer sampling and analytical methodologies. The working group identified phosphate content in DAP and MAP fertilizers as a major concern for commerce. The working group initiated a method screening and comparison project to assess method performance and to determine which methods, if any, could be considered best practice methods and, therefore, be deemed acceptable for use by the industry. In order to systematically review the acceptability of methods for consideration, the task force developed an assessment protocol outlined in a white paper involving three steps: (1) compile all known relevant methods practiced in global fertilizer trade, (2) review and evaluate methods based upon specific evaluation criteria, and (3) compare the methods that most closely fit the evaluation criteria by multilaboratory analysis of unknown materials for accuracy and repeatability. Six methods were evaluated for analysis of total phosphate in concentrated phosphate products. From these methods, four were determined to be acceptable as best practice methods. The study members proposed three of the methods, while a fourth method was commonly used among the participating laboratories. This publication

  9. Regulation of 3-Deoxy-d-arabino-Heptulosonic 7-Phosphate Acid Synthetase Activity in Relation to the Synthesis of the Aromatic Vitamins in Escherichia coli K-12

    Science.gov (United States)

    Wallace, B. J.; Pittard, J.

    1969-01-01

    Both in vivo and in vitro experiments on wild-type Escherichia coli K-12 and mutant strains possessing only single 3-deoxy-d-arabino-heptulosonic 7-phosphate acid (DAHP) synthetase isoenzymes indicated that, under conditions when all three isoenzymes are fully repressed, sufficient chorismate is still formed for the synthesis of aromatic vitamins. Under repressed conditions both DAHP synthetase (phe) and (trp), but not DAHP synthetase (tyr), were shown to contribute to vitamin production. PMID:4905534

  10. The impact of phosphate-balanced crystalloid infusion on acid-base homeostasis (PALANCE study): study protocol for a randomized controlled trial.

    Science.gov (United States)

    Pagel, Judith-Irina; Hulde, Nikolai; Kammerer, Tobias; Schwarz, Michaela; Chappell, Daniel; Burges, Alexander; Hofmann-Kiefer, Klaus; Rehm, Markus

    2017-07-10

    This study aims to investigate the effects of a modified, balanced crystalloid including phosphate in a perioperative setting in order to maintain a stable electrolyte and acid-base homeostasis in the patient. This is a single-centre, open-label, randomized controlled trial involving two parallel groups of female patients comparing a perioperative infusion regime with sodium glycerophosphate and Jonosteril® (treatment group) or Jonosteril® (comparator) alone. The primary endpoint is to maintain a stable concentration of weak acids [A(-)] according to the Stewart approach of acid-base balance. Secondary endpoints are measurement of serum phosphate levels, other acid-base parameters such as the strong ion difference (SID), the onset and severity of postoperative nausea and vomiting (PONV), electrolyte levels and their excretion in the urine, monitoring of renal function and glycocalyx components, haemodynamics, amounts of catecholamines and other vasopressors used and the safety of the infusion regime. Perioperative fluid replacement with the use of currently available crystalloid preparations still fail to maintain a stable acid-base balance and experts agree that common balanced solutions are still not ideal. This study aims to investigate the effectivity and safety of a new crystalloid solution by adding sodium glycerophosphate to a standardized crystalloid preparation in order to maintain a balanced perioperative acid-base homeostasis. EudraCT number 201002422520 . Registered on 30 November 2010.

  11. The role of glucosamine-6-phosphate deaminase at the early stages of Aspergillus niger growth in a high-citric-acid-yielding medium.

    Science.gov (United States)

    Solar, Tina; Tursic, Janja; Legisa, Matic

    2008-03-01

    Glucosamine-6-phosphate (GlcN6P) deaminase seems to be the main enzyme in Aspergillus niger cells responsible for rapid glucosamine accumulation during the early stages of growth in a high-citric-acid-yielding medium. By determining basic kinetic parameters on the isolated enzyme, a high affinity toward fructose-6-phosphate (Fru6P) was measured, while in the reverse direction the K(m) value for glucosamine-6-phosphate was lower than deaminases from other organisms measured so far. The enzyme characteristics of GlcN6P deaminase suggest it must compete with 6-phosphofructo-1-kinase (PFK1) for the common substrate-Fru6P in A. niger cells. Glucosamine accumulation seems therefore to remove an intermediate from the glycolytic flux, a situation which is reflected in slower citric acid accumulation and a specific growth rate after the germination of spores. When ammonium ions are depleted from the medium, one of the substrates for GlcN6P deaminase becomes limiting and Fru6P can be catabolised by PFK1 which enhances glycolytic flux. Other enzymatic features of GlcN6P deaminase such as pH optima for both aminating and deaminating reactions might play a significant role in rapid glucosamine accumulation during the early phase of fermentation and a slow consumption of aminosugar during the citric-acid-producing phase.

  12. [Preliminary application of injectable calcium phosphate cement/poly (lactic-co-glycolic acid) microspheres for extraction site preservation].

    Science.gov (United States)

    Mai, Yuying; Wu, Huihuang; Mai, Zhisong; Li, Xinghong; Huang, Linhui; Liao, Hongbing

    2014-03-01

    To investigate the feasibility of extraction site preservation using injectable calcium phosphate cement (CPC) combine with poly (lactic-co-glycolic acid) (PLGA) microspheres. Immediate extraction defects models were created in canine mandibles, and the defects were filled with CPC/PLGA (experimental group, E) , Bio-Oss (positive control, P), non-treatment (blank control, B) respectively. Dogs were sacrificed after 4, 8, 12 weeks post operation. Statistical analysis were conducted using SPSS 19. of radiological observation showed that there were not significantly different between groups in 4 and 8 week (P > 0.05). After 12 week,E (114.9 ± 8.4) were not significantly different compared with P (117.4 ± 12.1) (P > 0.05) , both were significantly higher than B (95.0 ± 12.6) (P B[(78.7 ± 2.7)%] > E[(69.2 ± 1.8)%] (P < 0.05). At 8, 12 week, results of P[(94.0 ± 2.3)% and (93.5 ± 1.9) %] and E[ (94.7 ± 1.1) % and (96.0 ± 0.9) %] were better than those of B[ (76.8 ± 3.0)% and (87.0 ± 2.4)%] (P < 0.05). The effect of CPC/PLGA repair immediate alveolar ridge defects is the same as that of Bio-Oss, and CPC/PLGA can be used as a material in extraction site preservation.

  13. The synthetic xylulose-1 phosphate pathway increases production of glycolic acid from xylose-rich sugar mixtures.

    Science.gov (United States)

    Alkim, Ceren; Trichez, Debora; Cam, Yvan; Spina, Lucie; François, Jean Marie; Walther, Thomas

    2016-01-01

    Glycolic acid (GA) is a two-carbon hydroxyacid with applications in the cosmetic, textile, and medical industry. Microbial GA production from all sugars can be achieved by engineering the natural glyoxylate shunt. The synthetic (d)-xylulose-1 phosphate (X1P) pathway provides a complementary route to produce GA from (d)-xylose. The simultaneous operation of the X1P and glyoxylate pathways increases the theoretical GA yield from xylose by 20 %, which may strongly improve GA production from hemicellulosic hydrolysates. We herein describe the construction of an E. coli strain that produces GA via the glyoxylate pathway at a yield of 0.31 , 0.29 , and 0.37 g/g from glucose, xylose, or a mixture of glucose and xylose (mass ratio: 33:66 %), respectively. When the X1P pathway operates in addition to the glyoxylate pathway, the GA yields on the three substrates are, respectively, 0.39 , 0.43 , and 0.47 g/g. Upon constitutive expression of the sugar permease GalP, the GA yield of the strain which simultaneously operates the glyoxylate and X1P pathways further increases to 0.63 g/g when growing on the glucose/xylose mixture. Under these conditions, the GA yield on the xylose fraction of the sugar mixture reaches 0.75 g/g, which is the highest yield reported to date. These results demonstrate that the synthetic X1P pathway has a very strong potential to improve GA production from xylose-rich hemicellulosic hydrolysates.

  14. Preparation of core-shell PAN nanofibers encapsulated α-tocopherol acetate and ascorbic acid 2-phosphate for photoprotection.

    Science.gov (United States)

    Wu, Xiao-Mei; Branford-White, Christopher J; Yu, Deng-Guang; Chatterton, Nicholas P; Zhu, Li-Min

    2011-01-01

    Magnesium l-ascorbic acid 2-phosphate (MAAP) and α-tocopherol acetate (α-TAc), as the stable vitamin C and vitamin E derivative, respectively, are often applied to skin care products for reducing UV damage. The encapsulation of MAAP (0.5%, g/mL) and α-TAc (5%, g/mL) together within the polyacrylonitrile (PAN) nanofibers was demonstrated using a coaxial electrospinning technique. The structure and morphology characterizations of the core-shell fibers MAAP/α-TAc-PAN were investigated by SEM, FTIR and XRD. As a negative control, the blend nanofibers MAAP/α-TAc/PAN were prepared from a normal electrospinning method. The results from SEM indicated that the morphology and diameter of the nanofibers were influenced by concentration of spinning solution, the polymer component of the shell, the carrying agent of the core and the fabricating methods, and the core-shell nanofibers obtained at the concentration of 8% had finer and uniform structure with the average diameters of 200 ± 15nm. From in vitro release studies it could be seen that both different fiber specimens showed a gradual increase in the amount of α-TAc or MAAP released from the nanofibers. Furthermore, α-TAc and MAAP released from the blend nanofibers showed the burst release at the maximum release of ∼15% and ∼40% during the first 6h, respectively, but their release amount from the core-shell nanofibers was only 10-12% during the initial part of the process. These results showed that core-shell nanofibers alleviated the initial burst release and gave better sustainability compared to that of the blend nanofibers. The present study would provide a basis for further optimization of processing conditions to obtain desired structured core-shell nanofibers and release kinetics for practical applications in dermal tissue. Copyright © 2010 Elsevier B.V. All rights reserved.

  15. Increased proliferation and replicative lifespan of isolated human corneal endothelial cells with L-ascorbic acid 2-phosphate.

    Science.gov (United States)

    Shima, Nobuyuki; Kimoto, Miwa; Yamaguchi, Masahiro; Yamagami, Satoru

    2011-11-07

    To explore an alternative culture method for human corneal endothelial cells (HCECs) and to examine the effect of l-ascorbic acid 2-phosphate (Asc-2P) on the growth of these cells. The influence of various mitogens, extracellular matrices (ECMs), and Asc-2P on growth of cultured HCECs was examined. HCECs were obtained from donors ranging in age from 12 to 74 years, and primary cultures and subcultures were performed with or without Asc-2P. Expanded HCECs were characterized with immunostaining and reverse transcription polymerase chain reaction (RT-PCR) and evaluated for generation of 8-hydroxy-2-deoxyguanosine (8-OHdG) with immunostaining and an enzyme-linked immunosorbent assay (ELISA). Culture with Asc-2P and bFGF on atelocollagen promoted the proliferation of HCECs in both primary cultures and subcultures as efficiently as conventional culture using ECM derived from bovine corneal endothelial cells. Zonula occludens-1, N-cadherin, connexin 43, and Na+/K+-ATPase were localized at plasma membranes of cultured HCECs. mRNAs of the voltage-dependent anion channels (VDAC2 and VDAC3), sodium bicarbonate cotransporter member 4 (SLC4A4), and chloride channel proteins (CLCN2 and CLCN3) were detected by RT-PCR. During multiple passages, cultures without Asc-2P showed a decrease in growth and irregular cell morphology, whereas cultures with Asc-2P sustained cell growth and maintained the characteristic polygonal morphology. ELISA for 8-OHdG showed that the levels in mitochondrial DNA significantly decreased when HCECs were subcultured with Asc-2P. Combination of Asc-2P and bFGF on atelocollagen allows successful culture for HCECs. Asc-2P extends the lifespan of cultured HCECs, partly due to protection against oxidative DNA damage.

  16. Polylactic acid-based porous scaffolds doped with calcium silicate and dicalcium phosphate dihydrate designed for biomedical application.

    Science.gov (United States)

    Gandolfi, Maria Giovanna; Zamparini, Fausto; Degli Esposti, Micaela; Chiellini, Federica; Aparicio, Conrado; Fava, Fabio; Fabbri, Paola; Taddei, Paola; Prati, Carlo

    2018-01-01

    Polylactic acid (PLA), dicalcium phosphate dihydrate (DCPD) and/or hydraulic calcium silicate (CaSi) have been used to prepare highly-porous scaffolds by thermally induced phase separation technique (TIPS). Three experimental mineral-doped formulations were prepared (PLA-10CaSi, PLA-5CaSi-5DCPD, PLA-10CaSi-10DCPD). Pure PLA scaffolds constituted the control group. Scaffolds were tested for their chemical-physical and biological properties, namely calcium release, alkalinizing activity, surface microchemistry and micromorphology by ESEM, apatite-forming ability by EDX, micro-Raman and IR spectroscopy, thermal properties by differential scanning calorimetry, mechanical properties by quasi-static parallel-plates compression testing, porosity by a standard water-absorption method and direct-contact cytotoxicity. All mineral-doped scaffolds released biologically relevant ions (biointeractive). A B-type carbonated apatite layer (thickness decreasing along the series PLA-10CaSi-10DCPD>PLA-10CaSi>PLA-5CaSi-5DCPD>PLA) was detected on the surface of all the 28d-aged scaffolds. Surface pores of fresh scaffolds ranged from 10 to 20μm in pure PLA to 10-100μm in PLA-10CaSi. An increase in porosity was detected in 28d-aged pure PLA scaffolds (approx. 30% of material loss with decrease of the PLA chain length); differently, in mineral-doped scaffolds, the PLA degradation was balanced by deposition/nucleation of apatite. All scaffolds showed absence of toxicity, in particular PLA-10CaSi-10DCPD. The designed scaffolds are biointeractive (release biologically relevant ions), nucleate apatite, possess high surface and internal open porosity and can be colonized by cells, appearing interesting materials for bone regeneration. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Phosphate Salts

    Science.gov (United States)

    ... phosphate doesn't improve running or cycling performance. Diabetes complication (diabetic ketoacidosis). Early research shows that giving potassium phosphate intravenously (by IV) does not improve a diabetes complication in which the body produces too many blood ...

  18. Preimplantation filling of tooth socket with beta-tricalcium phosphate/polylactic-polyglycolic acid (beta-TCP/PLGA) root analogue: clinical and histological analysis in a patient.

    Science.gov (United States)

    Koković, Vladimir; Todorović, Ljubomir

    2011-04-01

    Bone resorption is a physiological process after tooth extraction. The use of bone substitutes to fill the tooth socket is suggested to prevent bone resorption and establish good bone architecture for implant placement. A pure beta-tricalcium phosphate coated with copolymer (polylactic-polyglycolic acid) as a root analogue, is suitable for filling tooth sockets. We presented a patient successfully treated with root analogue after extraction of the right second lower premolar. Three months later, the patient was planned for the placement of six TE ITI dental implants into the mandible. During the sugery, the biopsy of bone-like tissue from the previously treated socket was taken. All the implants were immediately loaded due to good primary stability. Histological analysis of the specimen revealed fibrous healing in the area treated with root analogue. The use of beta-tricalcium phosphate coated with copolymers after tooth extraction enables satisfactory bone architecture for consequent implant treatment.

  19. A clean-up technology for the simultaneous determination of lysophosphatidic acid and sphingosine-1-phosphate by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using a phosphate-capture molecule, Phos-tag.

    Science.gov (United States)

    Morishige, Jun-ichi; Urikura, Mai; Takagi, Haruko; Hirano, Kaoru; Koike, Tohru; Tanaka, Tamotsu; Satouchi, Kiyoshi

    2010-04-15

    Lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P) are growth factor-like lipids having a phosphate group. The concentrations of these mediator lipids in blood are considered to be potential biomarkers for early detection of cancer or vascular diseases. Here, we report a method for simultaneous determination of LPA and S1P using Phos-tag, a zinc complex that specifically binds to a phosphate-monoester group. Although both LPA and S1P are hydrophilic compounds, we found that they acquire hydrophobic properties when they form complexes with Phos-tag. Based on this finding, we developed a method for the enrichment of LPA and S1P from biological samples. The first partition in a two-phase solvent system consisting of chloroform/methanol/water (1:1:0.9, v/v/v) is conducted for the removal of lipids. LPA and S1P are specifically extracted as Phos-tag complexes at the second partition by adding Phos-tag. The Phos-tag complexes of LPA and S1P are detectable by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and quantifiable based on the relative intensities of ions using 17:0 LPA and C17 S1P as internal standards. The protocol was validated by analyses of these mediator lipids in calf serum, a rat brain and a lung. The clean-up protocol is rapid, requires neither thin-layer chromatography (TLC) nor liquid chromatography (LC), and is applicable to both blood and solid tissue samples. We believe that our protocol will be useful for a routine analysis of LPA and S1P in many clinical samples. 2010 John Wiley & Sons, Ltd.

  20. The role of phosphate additive in stabilization of sulphuric-acid-based vanadium(V) electrolyte for all-vanadium redox-flow batteries

    Science.gov (United States)

    Roznyatovskaya, Nataliya V.; Roznyatovsky, Vitaly A.; Höhne, Carl-Christoph; Fühl, Matthias; Gerber, Tobias; Küttinger, Michael; Noack, Jens; Fischer, Peter; Pinkwart, Karsten; Tübke, Jens

    2017-09-01

    Catholyte in all-vanadium redox-flow battery (VRFB) which consists of vanadium salts dissolved in sulphuric acid is known to be stabilized by phosphoric acid to slow down the thermal aging at temperatures higher than 40 °C. To reveal the role of phosphoric acid, the thermally-induced aggregation is investigated using variable-temperature 51V, 31P, 17O, 1H nuclear magnetic resonance (NMR) spectroscopy and dynamic light scattering (DLS). The results indicate that the thermal stabilization of vanadium(V) electrolyte is attained by the involvement of monomeric and dimeric vanadium(V) species in the reaction with phosphoric acid which is concurrent to the formation of neutral hydroxo-aqua vanadium(V) precipitation precursor. The dimers are stabilized by counter ions due to association reaction or if such stabilization is not possible, precipitation of vanadium pentoxide is favored. The evolution of particles size distributions at 50 °C in electrolyte samples containing 1.6 M vanadium and 4.0 M total sulphate and the pathways of precipitate formation are discussed. The optimal total phosphate concentration is found to be of 0.15 M. However, the induction time is assumed to be dependent not only on the total phosphate concentrations, but also on the ratio of total vanadium(V) to sulphate concentrations.

  1. Solvent Extraction of Rare Earth Elements from a Nitric Acid Leach Solution of Apatite by Mixtures of Tributyl Phosphate and Di-(2-ethylhexyl) Phosphoric Acid

    Science.gov (United States)

    Ferdowsi, Ali; Yoozbashizadeh, Hossein

    2017-09-01

    Solvent extraction of rare earths from nitrate leach liquor of apatite using mixtures of tributyl phosphate (TBP) and di-(2-ethylhexyl) phosphoric acid (D2EHPA) was studied. The effects of nitrate and hydrogen ion concentration of the aqueous phase as well as the composition and concentration of extractants in the organic phase on the extraction behavior of lanthanum, cerium, neodymium, and yttrium were investigated. The distribution ratio of REEs increases by increasing the nitrate concentration in aqueous phase and concentration of extractants in organic phase, but the hydrogen ion concentration in aqueous phase has a decreasing effect. Yttrium as a heavy rare earth is more sensitive to these parameters than light rare earth elements. Although the composition of organic phase has a minor effect on the extraction of light rare earths, the percent of extraction of yttrium decreases dramatically by increasing the TBP content of organic phase. Mixtures of TBP and D2EHPA can show either synergism or antagonism extraction depending on the concentration and composition of extractants in organic phase. The best condition for separating rare earth elements in groups of heavy and light REEs can be achieved at high nitrate concentration, low H+ concentration, and high concentration of D2EHPA in organic phase. Separation of Ce and La by TBP and D2EHPA is practically impossible in the studied conditions; however, low nitrate concentration and high hydrogen ion concentration in aqueous phase and low concentration of extractants in organic phase favor the separation of Nd from other light rare earth elements.

  2. Solvent Extraction of Rare Earth Elements from a Nitric Acid Leach Solution of Apatite by Mixtures of Tributyl Phosphate and Di-(2-ethylhexyl) Phosphoric Acid

    Science.gov (United States)

    Ferdowsi, Ali; Yoozbashizadeh, Hossein

    2017-12-01

    Solvent extraction of rare earths from nitrate leach liquor of apatite using mixtures of tributyl phosphate (TBP) and di-(2-ethylhexyl) phosphoric acid (D2EHPA) was studied. The effects of nitrate and hydrogen ion concentration of the aqueous phase as well as the composition and concentration of extractants in the organic phase on the extraction behavior of lanthanum, cerium, neodymium, and yttrium were investigated. The distribution ratio of REEs increases by increasing the nitrate concentration in aqueous phase and concentration of extractants in organic phase, but the hydrogen ion concentration in aqueous phase has a decreasing effect. Yttrium as a heavy rare earth is more sensitive to these parameters than light rare earth elements. Although the composition of organic phase has a minor effect on the extraction of light rare earths, the percent of extraction of yttrium decreases dramatically by increasing the TBP content of organic phase. Mixtures of TBP and D2EHPA can show either synergism or antagonism extraction depending on the concentration and composition of extractants in organic phase. The best condition for separating rare earth elements in groups of heavy and light REEs can be achieved at high nitrate concentration, low H+ concentration, and high concentration of D2EHPA in organic phase. Separation of Ce and La by TBP and D2EHPA is practically impossible in the studied conditions; however, low nitrate concentration and high hydrogen ion concentration in aqueous phase and low concentration of extractants in organic phase favor the separation of Nd from other light rare earth elements.

  3. Network analysis and percolation transition in hydrogen bonded clusters: nitric acid and water extracted by tributyl phosphate.

    Science.gov (United States)

    Servis, Michael J; Wu, David T; Braley, Jenifer C

    2017-05-10

    Extraction of polar molecules by amphiphilic species results in a complex variety of clusters whose topologies and energetics control phase behavior and efficiency of liquid-liquid separations. A computational approach including quantum mechanical vibrational frequency calculations and molecular dynamics simulation with intermolecular network theory is used to provide a robust assessment of extractant and polar solute association through hydrogen bonding in the tributyl phosphate (TBP)/HNO3/H2O/dodecane system for the first time. The distribution of local topologies of the TBP/HNO3/H2O hydrogen bonded clusters is shown to be consistent with an equilibrium binding model. Mixed TBP/HNO3/H2O clusters are predicted that have not been previously observable in experiment due to limitations in scattering and spectroscopic resolution. Vibrational frequency calculations are compared with experimental data to validate the experimentally observed TBP-HNO3-HNO3 Chain structure. At high nitric acid and water loading, large hydrogen-bonded clusters of 20 to 80 polar solutes formed. The cluster sizes were found to be exponentially distributed, consistent with a constant average solute association free energy in that size range. Due to the deficit of hydrogen bond donors in the predominantly TBP/HNO3 organic phase, increased water concentrations lower the association free energy and enable growth of larger cluster sizes. For sufficiently high water concentrations, changes in the cluster size distribution are found to be consistent with the formation of a percolating cluster rather than reverse micelles, as has been commonly assumed for the occurrence of an extractant-rich third phase in metal-free solvent extraction systems. Moreover, the compositions of the large clusters leading to percolation agrees with the 1 : 3 TBP : HNO3 ratio reported in the experimental literature for TBP/HNO3/H2O third phases. More generally, the network analysis of cluster formation from atomic

  4. Effectiveness of trisodium phosphate, acidified sodium chlorite, citric acid, and peroxyacids against pathogenic bacteria on poultry during refrigerated storage.

    Science.gov (United States)

    del Río, Elena; Muriente, Rebeca; Prieto, Miguel; Alonso-Calleja, Carlos; Capita, Rosa

    2007-09-01

    The effects of dipping treatments (15 min) in potable water or in solutions (wt/vol) of 12% trisodium phosphate (TSP), 1,200 ppm acidified sodium chlorite (ASC), 2% citric acid (CA), and 220 ppm peroxyacids (PA) on inoculated pathogenic bacteria (Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, Salmonella Enteritidis, Escherichia coli, and Yersinia enterocolitica) and skin pH were investigated throughout storage of chicken legs (days 0, 1, 3, and 5) at 3 +/- 1 degrees C. All chemical solutions reduced microbial populations (P 0.05) were observed on water-dipped and control legs. Type of treatment, microbial group, and sampling day influenced microbial counts (P < 0.001). Average reductions with regard to control samples were 0.28 to 2.41 log CFU/g with TSP, 0.33 to 3.15 log CFU/g with ASC, 0.82 to 1.97 log CFU/g with CA, and 0.07 to 0.96 log CFU/g with PA. Average reductions were lower (P < 0.001) for gram-positive (0.96 log CFU/g) than for gram-negative (1.33 log CFU/g) bacteria. CA and ASC were the most effective antimicrobial compounds against gram-positive and gram-negative bacteria, respectively. TSP was the second most effective compound for both bacterial groups. Average microbial reductions per gram of skin were 0.87 log CFU/g with TSP, 0.86 log CFU/g with ASC, 1.39 log CFU/g with CA, and 0.74 log CFU/g with PA for gram-positive bacteria, and 1.28 log CFU/g with TSP, 2.03 log CFU/g with ASC, 1.23 log CFU/g with CA, and 0.78 log CFU/g with PA for gram-negative bacteria. With only a few exceptions, microbial reductions in TSP- and ASC-treated samples decreased and those in samples treated with CA increased throughout storage. Samples treated with TSP and samples dipped in CA and ASC had the highest and lowest pH values, respectively, after treatment. The pH of the treated legs tended to return to normal (6.3 to 6.6) during storage. However, at the end of storage, the pH of legs treated with TSP remained higher and that of legs treated with CA

  5. The bone-regenerative properties of Emdogain adsorbed onto poly(D,L-lactic-coglycolic acid)/calcium phosphate composites in an ectopic and an orthotopic rat model.

    Science.gov (United States)

    Plachokova, A S; van den Dolder, J; Jansen, J A

    2008-02-01

    The aim of this study was to evaluate the bone-regenerative properties of Emdogain in osseous and nonosseous sites. For the orthotopic study, unloaded poly(D,L-lactic-coglycolic acid)/calcium phosphate implants, and poly(D,L-lactic-coglycolic acid)/calcium phosphate implants loaded with different concentrations (0.25, 0.50 or 0.80 mg per implant) of enamel matrix derivative (EMD), were inserted into cranial defects of 24 rats. The implantation time was 4 wk. For the ectopic study, 32 implants were placed subcutaneously. The same study period and groups as in the orthotopic study were used. Methods of evaluation consisted of descriptive histology, histomorphometry and an in vitro EMD-release study. In the orthotopic study, new bone formation was most abundant in unloaded implants followed by 0.50-mg EMD composites. Histomorphometric measurements showed 54 +/- 15.0% bone ingrowth for unloaded implants, 19 +/- 22.5% bone ingrowth for 0.25-mg EMD composites, 40 +/- 23.6% bone ingrowth for 0.50-mg EMD composites and 26 +/- 17.6% bone ingrowth for 0.80-mg EMD composites. Light microscopic analysis of the subcutaneous sections from the ectopic study revealed no bone formation in any group after 4 wk. The in vitro release study showed 60% cumulative EMD release after 4 wk. Emdogain is not osteoinductive and is not able to enhance bone healing in combination with an osteoconductive material, such as poly(D,L-lactic-coglycolic acid)/calcium phosphate cement.

  6. Topical application of disodium isostearyl 2-O-L-ascorbyl phosphate, an amphiphilic ascorbic acid derivative, reduces neuropathic hyperalgesia in rats.

    Science.gov (United States)

    Okubo, Kazumasa; Nakanishi, Hiroki; Matsunami, Maho; Shibayama, Hiroharu; Kawabata, Atsufumi

    2012-06-01

    Ca(v) 3.2 T-type calcium channels, targeted by H(2) S, are involved in neuropathic hyperalgesia in rats and ascorbic acid inhibits Ca(v) 3.2 channels. Therefore, we evaluated the effects of intraplantar (i.pl.) administration of ascorbic acid or topical application of disodium isostearyl 2-O-L-ascorbyl phosphate (DI-VCP), a skin-permeable ascorbate derivative on hyperalgesia induced by NaHS, an H(2) S donor, and on neuropathic hyperalgesia. In rats mechanical hyperalgesia was evoked by i.pl. NaHS, and neuropathic hyperalgesia was induced by L5 spinal nerve cutting (L5SNC) or by repeated administration of paclitaxel, an anti-cancer drug. Dermal ascorbic acid levels were determined colorimetrically. The NaHS-evoked Ca(v) 3.2 channel-dependent hyperalgesia was inhibited by co-administered ascorbic acid. Topical application of DI-VCP, but not ascorbic acid, prevented the NaHS-evoked hyperalgesia, and also increased dermal ascorbic acid levels. Neuropathic hyperalgesia induced by L5SNC or paclitaxel was reversed by i.pl. NNC 55-0396, a selective T-type calcium channel blocker, ascorbic acid or DI-VCP, and by topical DI-VCP, but not by topical ascorbic acid. The effects of i.pl. ascorbic acid and topical DI-VCP in the paclitaxel-treated rats were characterized by the faster onset and greater magnitude, compared with their effects in the L5SNC rats. Dermal ascorbic acid levels in the hindpaw significantly decreased after paclitaxel treatment, but not L5SNC, which was reversed by topical DI-VCP. Ascorbic acid, known to inhibit Ca(v) 3.2 channels, suppressed neuropathic hyperalgesia. DI-VCP ointment for topical application may be of benefit in the treatment of neuropathic pain. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

  7. Topical application of disodium isostearyl 2-O-L-ascorbyl phosphate, an amphiphilic ascorbic acid derivative, reduces neuropathic hyperalgesia in rats

    Science.gov (United States)

    Okubo, Kazumasa; Nakanishi, Hiroki; Matsunami, Maho; Shibayama, Hiroharu; Kawabata, Atsufumi

    2012-01-01

    BACKGROUND AND PURPOSE Cav3.2 T-type calcium channels, targeted by H2S, are involved in neuropathic hyperalgesia in rats and ascorbic acid inhibits Cav3.2 channels. Therefore, we evaluated the effects of intraplantar (i.pl.) administration of ascorbic acid or topical application of disodium isostearyl 2-O-L-ascorbyl phosphate (DI-VCP), a skin-permeable ascorbate derivative on hyperalgesia induced by NaHS, an H2S donor, and on neuropathic hyperalgesia. EXPERIMENTAL APPROACH In rats mechanical hyperalgesia was evoked by i.pl. NaHS, and neuropathic hyperalgesia was induced by L5 spinal nerve cutting (L5SNC) or by repeated administration of paclitaxel, an anti-cancer drug. Dermal ascorbic acid levels were determined colorimetrically. KEY RESULTS The NaHS-evoked Cav3.2 channel-dependent hyperalgesia was inhibited by co-administered ascorbic acid. Topical application of DI-VCP, but not ascorbic acid, prevented the NaHS-evoked hyperalgesia, and also increased dermal ascorbic acid levels. Neuropathic hyperalgesia induced by L5SNC or paclitaxel was reversed by i.pl. NNC 55–0396, a selective T-type calcium channel blocker, ascorbic acid or DI-VCP, and by topical DI-VCP, but not by topical ascorbic acid. The effects of i.pl. ascorbic acid and topical DI-VCP in the paclitaxel-treated rats were characterized by the faster onset and greater magnitude, compared with their effects in the L5SNC rats. Dermal ascorbic acid levels in the hindpaw significantly decreased after paclitaxel treatment, but not L5SNC, which was reversed by topical DI-VCP. CONCLUSIONS AND IMPLICATIONS Ascorbic acid, known to inhibit Cav3.2 channels, suppressed neuropathic hyperalgesia. DI-VCP ointment for topical application may be of benefit in the treatment of neuropathic pain. PMID:22229645

  8. Matching phosphate and maleate buffer systems for dissolution of weak acids: Equivalence in terms of buffer capacity of bulk solution or surface pH?

    Science.gov (United States)

    Cristofoletti, Rodrigo; Dressman, Jennifer B

    2016-06-01

    The development of in vitro dissolution tests able to anticipate the in vivo fate of drug products has challenged pharmaceutical scientists over time, especially in the case of ionizable compounds. In the seminal model proposed by Mooney et al. thirty-five years ago, the pH at the solid-liquid interface (pH0) was identified as a key parameter in predicting dissolution rate. In the current work it is demonstrated that the in vitro dissolution of the weak acid ibuprofen in maleate and phosphate buffer systems is a function of the pH0, which in turn is affected by properties of the drug and the medium. The reported pH0 for ibuprofen dissolution in bicarbonate buffer, the predominant buffer species in the human small intestine under fasting conditions, can be achieved by reducing the phosphate buffer concentration to 5.0mM or the maleate buffer concentration to 2.2mM. Using this approach to identify the appropriate buffer/buffer capacity combination for in vitro experiments in FaSSIF-type media, it would be possible to increase the physiological relevance of this important biopharmaceutics tool. However, the necessity of monitoring and adjusting the bulk pH during the experiments carried out in 5.0mM phosphate or 2.2mM maleate buffers must also be taken into consideration. Copyright © 2016 Elsevier B.V. All rights reserved.

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

    NARCIS (Netherlands)

    Ruhe, P.Q.; Hedberg, E.L.; Padron, N.T.; Spauwen, P.H.M.; Jansen, J.A.; Mikos, A.G.

    2006-01-01

    Calcium phosphate (Ca-P) cements are injectable, self-setting ceramic pastes generally known for their favorable bone response. Ingrowth of bone and subsequent degradation rates can be enhanced by the inclusion of macropores. Initial porosity can be induced by CO(2) foaming during setting of the

  10. Efficacité de la roche phosphatée de Matongo au travers d'un compostage sur une culture de pomme de terre sur un sol acide de Rabiro (Burundi

    Directory of Open Access Journals (Sweden)

    Van den Berghe, C.

    1993-01-01

    Full Text Available Efficiency of phosphatic rock from Matongo applied in the composting process on potatoes on an acid soil of Rabiro. In the frame of the Cooperation between the CVHA (Cultures Vivrieres de Haute Altitute Project and the Program of Fertilisation of the Agro-systems on Altitude (FAVA of the Faculty of Agricultural Sciences in Burundi, the local phosphatic rock from Matongo has been compared to diammonium-phosphate when added in the composting process. The field trials with potatoes have shown that both phosphate sources have the same fertilizing value when the enriched compost was applied at the dose of 20 t/ha. It is very interesting from agricultural and economical viewpoint to use this phosphatic rock in combination with compost.

  11. Phosphate Mines, Jordan

    Science.gov (United States)

    2008-01-01

    Jordan's leading industry and export commodities are phosphate and potash, ranked in the top three in the world. These are used to make fertilizer. The Jordan Phosphate Mines Company is the sole producer, having started operations in 1935. In addition to mining activities, the company produces phosphoric acid (for fertilizers, detergents, pharmaceuticals), diammonium phosphate (for fertilizer), sulphuric acid (many uses), and aluminum fluoride (a catalyst to make aluminum and magnesium). The image covers an area of 27.5 x 49.4 km, was acquired on September 17, 2005, and is located near 30.8 degrees north latitude, 36.1 degrees east longitude. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  12. The application of chitosan/collagen/hyaluronic acid sponge cross-linked by dialdehyde starch addition as a matrix for calcium phosphate in situ precipitation.

    Science.gov (United States)

    Kaczmarek, B; Sionkowska, A; Osyczka, A M

    2018-02-01

    Scaffolds based on chitosan, collagen and hyaluronic acid, cross-linked by dialdehyde starch were obtained through the freeze-drying method. The porous structures were used as matrixes for calcium phosphate in situ precipitation. Composites were characterized by different analyses, e.g. infrared spectroscopy, SEM images, porosity, density, and mechanical tests. Moreover, an examination involving the energy dispersive X-ray spectroscopic method was carried out for the calcium and phosphorus ratio determination. In addition, the adhesion and proliferation of human osteosarcoma SaOS-2 cells were examined on the obtained scaffolds. The results showed that the properties of the scaffolds based on chitosan, collagen, and hyaluronic acid can be modified by dialdehyde starch addition. The mechanical parameters (i.e. compressive modulus and maximum compressive force), porosity, and density of the material were improved. Calcium phosphate was deposited in the scaffolds at the Ca/P ratio ∼2. SEM images showed the homogeneous structure, with interconnected pores. The cross-linker addition and an inorganic compound precipitation improved the biocompatibility of the scaffolds. The obtained materials can provide the support required in tissue engineering and regenerative medicine. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Synthesis, characterization and fuel cell performance tests of boric acid and boron phosphate doped, sulphonated and phosphonated poly(vinyl alcohol) based composite membranes

    Science.gov (United States)

    Şahin, Alpay; Ar, İrfan

    2015-08-01

    The aim of this study is to synthesize a composite membrane having high proton conductivity, ion exchange capacity and chemical stability. In order to achieve this aim, poly(vinyl alcohol) (PVA) based composite membranes are synthesized by using classic sol-gel method. Boric acid (H3BO3) and boron phosphate (BPO4) are added to the membrane matrix in different ratios in order to enhance the membrane properties. Characterization tests, i.e; FT-IR analysis, mechanical strength tests, water hold-up capacities, swelling properties, ion exchange capacities, proton conductivities and fuel cell performance tests of synthesized membranes are carried out. As a result of performance experiments highest performance values are obtained for the membrane containing 15% boron phosphate at 0.6 V and 750 mA/cm2. Water hold-up capacity, swelling ratio, ion exchange capacity and proton conductivity of this membrane are found as 56%, 8%, 1.36 meq/g and 0.37 S/cm, respectively. These values are close to the values obtained ones for perfluorosulphonic acid membranes. Therefore this membrane can be regarded as a promising candidate for usage in fuel cells.

  14. Tuning the degradation rate of calcium phosphate cements by incorporating mixtures of polylactic-co-glycolic acid microspheres and glucono-delta-lactone microparticles.

    Science.gov (United States)

    Sariibrahimoglu, Kemal; An, Jie; van Oirschot, Bart A J A; Nijhuis, Arnold W G; Eman, Rhandy M; Alblas, Jacqueline; Wolke, Joop G C; van den Beucken, Jeroen J J P; Leeuwenburgh, Sander C G; Jansen, John A

    2014-11-01

    Calcium phosphate cements (CPCs) are frequently used as synthetic bone graft materials in view of their excellent osteocompatibility and clinical handling behavior. Hydroxyapatite-forming CPCs, however, degrade at very low rates, thereby limiting complete bone regeneration. The current study has investigated whether degradation of apatite-forming cements can be tuned by incorporating acid-producing slow-resorbing poly(D,L-lactic-co-glycolic) acid (PLGA) porogens, fast-resorbing glucono-delta-lactone (GDL) porogens, or mixtures thereof. The physicochemical, mechanical, and degradation characteristics of these CPC formulations were systematically analyzed upon soaking in phosphate-buffered saline (PBS). In parallel, various CPC formulations were implanted intramuscularly and orthotopically on top of the transverse process of goats followed by analysis of the soft tissue response and bone ingrowth after 12 weeks. In vitro degradation of GDL was almost completed after 2 weeks, as evidenced by characterization of the release of gluconic acid, while PLGA-containing CPCs released glycolic acid throughout the entire study (12 weeks), resulting in a decrease in compression strength of CPC. Extensive in vitro degradation of the CPC matrix was observed upon simultaneous incorporation of 30% PLGA-10% GDL. Histomorphometrical evaluation of the intramuscularly implanted samples revealed that all CPCs exhibited degradation, accompanied by an increase in capsule thickness. In the in vivo goat transverse process model, incorporation of 43% PLGA, 30% PLGA-5% GDL, and 30% PLGA-10% GDL in CPC significantly increased bone formation and resulted in higher bone height compared with both 10% GDL and 20% GDL-containing CPC samples.

  15. Modulation of the Glycerol Phosphate availability led to concomitant reduction in the citric acid excretion and increase in lipid content and yield in Yarrowia lipolytica.

    Science.gov (United States)

    Sagnak, Rana; Cochot, Sandrine; Molina-Jouve, Carole; Nicaud, Jean-Marc; Guillouet, Stéphane E

    2017-11-02

    In order to improve TriAcylGycerol (TAG) lipids accumulation in the yeast Yarrowia lipolytica on glucose, double over-expression of the major acyl-CoA:diacylglycerol acyltransferase encoding gene (ylDGA2) and of the glycerol-phosphate dehydrogenase encoding gene (ylGPD1) was carried out. The genes were over-expressed in a strain impaired for the mobilization of the accumulated lipids, through the deletion of the genes encoding acyl-coenzyme A oxidases (POX1-6 genes) and the deletion of the very efficient lipase attached to the lipid bodies, encoded by ylTGL4. This metabolic engineering strategy had the objective of pulling the C-flow into the TAG synthesis by increasing the availability of glycerol-3-phosphate and its binding to fatty acids for the TAG synthesis. This strain showed a strong improvement in production performances on glucose in terms of lipid content (increase from 18 to 55%), lipid yield (increase from 0,035 to 0.14gg -1) and by-product formation (decrease in citric acid yield from 0.68 to 0.4gg -1). For developing bioprocess for the production of triacylglycerol from renewable carbon sources as glucose it is of first importance to control the C/N ratio in order to avoid citric acid excretion during lipid accumulation. Our engineered strain showed a delay in the onset of citric acid excretion as suggested by the 15% modulation of the critical C/N ratio. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Photocatalytic Aerobic Phosphatation of Alkenes.

    Science.gov (United States)

    Depken, Christian; Krätzschmar, Felix; Rieger, Rene; Rode, Katharina; Breder, Alexander

    2018-02-23

    A catalytic regime for the direct phosphatation of simple, non-polarized alkenes has been devised that is based on using ordinary, non-activated phosphoric acid diesters as the phosphate source and O 2 as the terminal oxidant. The title method enables the direct and highly economic construction of a diverse range of allylic phosphate esters. From a conceptual viewpoint, the aerobic phosphatation is entirely complementary to traditional methods for phosphate ester formation, which predominantly rely on the use of prefunctionalized or preactivated reactants, such as alcohols and phosphoryl halides. The title transformation is enabled by the interplay of a photoredox and a selenium π-acid catalyst and involves a sequence of single-electron-transfer processes. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Preparation of porous lanthanum phosphate with templates

    Energy Technology Data Exchange (ETDEWEB)

    Onoda, Hiroaki, E-mail: onoda@kpu.ac.jp [Department of Informatics and Environmental Sciences, Faculty of Life and Environmental Sciences, Kyoto Prefectural University, 1-5, Shimogamo Nakaragi-cyo, Sakyo-ku, Kyoto 606-8522 (Japan); Ishima, Yuya [Department of Applied Chemistry, Faculty of Life Sciences, Ritsumeikan University, 1-1-1, Nojihigashi, Kusatsu, Shiga 525-8577 (Japan); Takenaka, Atsushi [Department of Materials Science, Yonago National College of Technology, 4448, Hikona-cho, Yonago, Tottori 683-8502 (Japan); Tanaka, Isao [Department of Materials Science and Engineering, Faculty of Engineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)

    2009-08-05

    Malonic acid, propionic acid, glycine, n-butylamine, and urea were added to the preparation of lanthanum phosphate from lanthanum nitrate and phosphoric acid solutions. All additives were taken into lanthanum phosphate particles. The additives that have a basic site were easy to contain in precipitates. The addition of templates improved the specific surface area of lanthanum phosphate. The amount of pore, with radius smaller than 4 nm, increased with the addition of templates. The remained additives had influence on the acidic properties of lanthanum phosphate.

  18. Complexes of Silver(I Ions and Silver Phosphate Nanoparticles with Hyaluronic Acid and/or Chitosan as Promising Antimicrobial Agents for Vascular Grafts

    Directory of Open Access Journals (Sweden)

    Vojtech Adam

    2013-06-01

    Full Text Available Polymers are currently widely used to replace a variety of natural materials with respect to their favourable physical and chemical properties, and due to their economic advantage. One of the most important branches of application of polymers is the production of different products for medical use. In this case, it is necessary to face a significant disadvantage of polymer products due to possible and very common colonization of the surface by various microorganisms that can pose a potential danger to the patient. One of the possible solutions is to prepare polymer with antibacterial/antimicrobial properties that is resistant to bacterial colonization. The aim of this study was to contribute to the development of antimicrobial polymeric material ideal for covering vascular implants with subsequent use in transplant surgery. Therefore, the complexes of polymeric substances (hyaluronic acid and chitosan with silver nitrate or silver phosphate nanoparticles were created, and their effects on gram-positive bacterial culture of Staphylococcus aureus were monitored. Stages of formation of complexes of silver nitrate and silver phosphate nanoparticles with polymeric compounds were characterized using electrochemical and spectrophotometric methods. Furthermore, the antimicrobial activity of complexes was determined using the methods of determination of growth curves and zones of inhibition. The results of this study revealed that the complex of chitosan, with silver phosphate nanoparticles, was the most suitable in order to have an antibacterial effect on bacterial culture of Staphylococcus aureus. Formation of this complex was under way at low concentrations of chitosan. The results of electrochemical determination corresponded with the results of spectrophotometric methods and verified good interaction and formation of the complex. The complex has an outstanding antibacterial effect and this effect was of several orders higher compared to other

  19. The N-Acetylmuramic Acid 6-Phosphate Phosphatase MupP Completes the Pseudomonas Peptidoglycan Recycling Pathway Leading to Intrinsic Fosfomycin Resistance

    Directory of Open Access Journals (Sweden)

    Marina Borisova

    2017-03-01

    Full Text Available Bacterial cells are encased in and stabilized by a netlike peptidoglycan (PGN cell wall that undergoes turnover during bacterial growth. PGN turnover fragments are frequently salvaged by the cells via a pathway referred to as PGN recycling. Two different routes for the recycling of the cell wall sugar N-acetylmuramic acid (MurNAc have been recognized in bacteria. In Escherichia coli and related enterobacteria, as well as in most Gram-positive bacteria, MurNAc is recovered via a catabolic route requiring a MurNAc 6-phosphate etherase (MurQ in E. coli enzyme. However, many Gram-negative bacteria, including Pseudomonas species, lack a MurQ ortholog and use an alternative, anabolic recycling route that bypasses the de novo biosynthesis of uridyldiphosphate (UDP-MurNAc, the first committed precursor of PGN. Bacteria featuring the latter pathway become intrinsically resistant to the antibiotic fosfomycin, which targets the de novo biosynthesis of UDP-MurNAc. We report here the identification and characterization of a phosphatase enzyme, named MupP, that had been predicted to complete the anabolic recycling pathway of Pseudomonas species but has remained unknown so far. It belongs to the large haloacid dehalogenase family of phosphatases and specifically converts MurNAc 6-phosphate to MurNAc. A ΔmupP mutant of Pseudomonas putida was highly susceptible to fosfomycin, accumulated large amounts of MurNAc 6-phosphate, and showed lower levels of UDP-MurNAc than wild-type cells, altogether consistent with a role for MupP in the anabolic PGN recycling route and as a determinant of intrinsic resistance to fosfomycin.

  20. Electrochemical oxidation of acid black 210 dye on the boron-doped diamond electrode in the presence of phosphate ions: Effect of current density, pH, and chloride ions

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Carla Regina [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Av. Bandeirantes, 3900, CEP 14040-901, Ribeirao Preto, SP (Brazil); Montilla, Francisco; Morallon, Emilia [Departamento de Quimica Fisica, Universidad de Alicante, Apartado de Correos 99, E-03080, Alicante (Spain); Olivi, Paulo [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Av. Bandeirantes, 3900, CEP 14040-901, Ribeirao Preto, SP (Brazil)], E-mail: olivip@ffclrp.usp.br

    2009-11-30

    The electrochemical oxidation of acid black 210 dye (AB-210) on the boron-doped diamond (BDD) was investigated under different pH conditions. The best performance for the AB-210 oxidation occurred in alkaline phosphate solution. This is probably due to oxidizing agents such as phosphate radicals and peroxodiphosphate ions, which can be electrochemically produced with good yields on the BDD anode, mainly in alkaline solution. Under this condition, the COD (chemical oxygen demand) removal was higher than that obtained from the model proposed by Comninellis. Electrolyses performed in phosphate buffer and in the presence of chloride ions resulted in faster COD and color removals in acid and neutral solutions, but in alkaline phosphate solution, a better performance in terms of TOC removal was obtained in the absence of chloride. Moreover, organochloride compounds were detected in all electrolyses performed in the presence of chloride. The AB-210 electrooxidation on BDD using phosphate as supporting electrolyte proved to be interesting since oxidizing species generated from phosphate ions were able to completely degrade the dye without producing organochloride compounds.

  1. Further increased production of free fatty acids by overexpressing a predicted transketolase gene of the pentose phosphate pathway in Aspergillus oryzae faaA disruptant.

    Science.gov (United States)

    Tamano, Koichi; Miura, Ai

    2016-09-01

    Free fatty acids are useful as source materials for the production of biodiesel fuel and various chemicals such as pharmaceuticals and dietary supplements. Previously, we attained a 9.2-fold increase in free fatty acid productivity by disrupting a predicted acyl-CoA synthetase gene (faaA, AO090011000642) in Aspergillus oryzae. In this study, we achieved further increase in the productivity by overexpressing a predicted transketolase gene of the pentose phosphate pathway in the faaA disruptant. The A. oryzae genome is predicted to have three transketolase genes and overexpression of AO090023000345, one of the three genes, resulted in phenotypic change and further increase (corresponding to an increased production of 0.38 mmol/g dry cell weight) in free fatty acids at 1.4-fold compared to the faaA disruptant. Additionally, the biomass of hyphae increased at 1.2-fold by the overexpression. As a result, free fatty acid production yield per liter of liquid culture increased at 1.7-fold by the overexpression.

  2. Tantalum oxide and barium sulfate as radiopacifiers in injectable calcium phosphate-poly(lactic-co-glycolic acid) cements for monitoring in vivo degradation.

    Science.gov (United States)

    Hoekstra, Jan Willem M; van den Beucken, Jeroen J J P; Leeuwenburgh, Sander C G; Bronkhorst, Ewald M; Meijer, Gert J; Jansen, John A

    2014-01-01

    Monitoring the degradation of calcium phosphate-based bone substitute materials in vivo by means of noninvasive techniques (e.g., radiography) is often a problem due to the chemical resemblance of those substitutes with the mineral phase of bone. In the view of that, the present study aimed at enhancing the radiopacity of calcium phosphate cement enriched with poly(lactic-co-glycolic acid) (CPC-PLGA) microspheres, by adding tantalum oxide (Ta2O5) or the more traditional radiopacifier barium sulfate (BaSO4). The radiopacifying capacity of these radiopacifiers was first evaluated in vitro by microcomputed tomography (μCT). Thereafter, both radiopacifiers were tested in vivo using a distal femoral condyle model in rabbits, with subsequent ex vivo μCT analysis in parallel with histomorphometry. Addition of either one of the radiopacifiers proved to enhance radiopacity of CPC-PLGA in vitro. The in vivo experiment showed that both radiopacifiers did not induce alterations in biological performance compared to plain CPC-PLGA, hence both radiopacifiers can be considered safe and biocompatible. The histomorphometrical assessment of cement degradation and bone formation showed similar values for the three experimental groups. Interestingly, μCT analysis showed that monitoring cement degradation becomes feasible upon incorporation of either type of radiopacifier, albeit that BaSO4 showed more accuracy compared to Ta2O5. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

  3. Permeation and metabolism of a novel ascorbic acid derivative, disodium isostearyl 2-O-L-ascorbyl phosphate, in human living skin equivalent models.

    Science.gov (United States)

    Shibayama, H; Hisama, M; Matsuda, S; Ohtsuki, M

    2008-01-01

    A novel amphiphilic vitamin C (VC) derivative, disodium isostearyl 2-O-L-ascorbyl phosphate (VCP-IS-2Na), which possesses a C(18) alkyl chain attached to a stable ascorbate derivative, sodium L-ascorbic acid 2-phosphate (VCP-Na), was evaluated as a topical prodrug of VC with transdermal activity in human living skin equivalent (LSE) models. The permeation assay used was EPI-606X in the Franz-type diffusion cell system. VCP-IS-2Na exhibited much better permeability than VC and VCP-Na. The accumulation assays applied were EPI-200X and LSE-high by the dynamic system. The increased skin accumulation of VCP-IS-2Na was superior to that of VCP-Na and VC. VCP-IS-2Na that is susceptible to enzymatic hydrolysis by esterase and/or phosphatase released VC in the skin. Measurement of the metabolites that permeated and accumulated from the skin model suggested that VCP-IS-2Na was mainly metabolized via VCP-Na to VC in EPI-606X and EPI-200X, while it was mainly metabolized directly to VC in TESTSKIN LSE-high. Thus, these characteristics indicate that the novel VC derivative, VCP-IS-2Na, may be advantageous as a readily available source of VC for skin care applications. (c) 2008 S. Karger AG, Basel.

  4. Plastidial glyceraldehyde-3-phosphate dehydrogenase deficiency leads to altered root development and affects the sugar and amino acid balance in Arabidopsis.

    Science.gov (United States)

    Muñoz-Bertomeu, Jesús; Cascales-Miñana, Borja; Mulet, Jose Miguel; Baroja-Fernández, Edurne; Pozueta-Romero, Javier; Kuhn, Josef M; Segura, Juan; Ros, Roc

    2009-10-01

    Glycolysis is a central metabolic pathway that, in plants, occurs in both the cytosol and the plastids. The glycolytic glyceraldehyde-3-phosphate dehydrogenase (GAPDH) catalyzes the conversion of glyceraldehyde-3-phosphate to 1,3-bisphosphoglycerate with concomitant reduction of NAD(+) to NADH. Both cytosolic (GAPCs) and plastidial (GAPCps) GAPDH activities have been described. However, the in vivo functions of the plastidial isoforms remain unresolved. In this work, we have identified two Arabidopsis (Arabidopsis thaliana) chloroplast/plastid-localized GAPDH isoforms (GAPCp1 and GAPCp2). gapcp double mutants display a drastic phenotype of arrested root development, dwarfism, and sterility. In spite of their low gene expression level as compared with other GAPDHs, GAPCp down-regulation leads to altered gene expression and to drastic changes in the sugar and amino acid balance of the plant. We demonstrate that GAPCps are important for the synthesis of serine in roots. Serine supplementation to the growth medium rescues root developmental arrest and restores normal levels of carbohydrates and sugar biosynthetic activities in gapcp double mutants. We provide evidence that the phosphorylated pathway of Ser biosynthesis plays an important role in supplying serine to roots. Overall, these studies provide insights into the in vivo functions of the GAPCps in plants. Our results emphasize the importance of the plastidial glycolytic pathway, and specifically of GAPCps, in plant primary metabolism.

  5. Biochemical and molecular characterization of potential phosphate-solubilizing bacteria in acid sulfate soils and their beneficial effects on rice growth.

    Directory of Open Access Journals (Sweden)

    Qurban Ali Panhwar

    Full Text Available A study was conducted to determine the total microbial population, the occurrence of growth promoting bacteria and their beneficial traits in acid sulfate soils. The mechanisms by which the bacteria enhance rice seedlings grown under high Al and low pH stress were investigated. Soils and rice root samples were randomly collected from four sites in the study area (Kelantan, Malaysia. The topsoil pH and exchangeable Al ranged from 3.3 to 4.7 and 1.24 to 4.25 cmol(c kg(-1, respectively, which are considered unsuitable for rice production. Total bacterial and actinomycetes population in the acidic soils were found to be higher than fungal populations. A total of 21 phosphate-solubilizing bacteria (PSB including 19 N2-fixing strains were isolated from the acid sulfate soil. Using 16S rRNA gene sequence analysis, three potential PSB strains based on their beneficial characteristics were identified (Burkholderia thailandensis, Sphingomonas pituitosa and Burkholderia seminalis. The isolated strains were capable of producing indoleacetic acid (IAA and organic acids that were able to reduce Al availability via a chelation process. These PSB isolates solubilized P (43.65% existing in the growth media within 72 hours of incubation. Seedling of rice variety, MR 219, grown at pH 4, and with different concentrations of Al (0, 50 and 100 µM was inoculated with these PSB strains. Results showed that the bacteria increased the pH with a concomitant reduction in Al concentration, which translated into better rice growth. The improved root volume and seedling dry weight of the inoculated plants indicated the potential of these isolates to be used in a bio-fertilizer formulation for rice cultivation on acid sulfate soils.

  6. The mechanism of dephosphorylation of bis(2,4-dinitrophenyl) phosphate in mixed micelles of cationic surfactants and lauryl hydroxamic acid.

    Science.gov (United States)

    Silva, Marcelo; Mello, Renata S; Farrukh, M Akhyar; Venturini, Janio; Bunton, Clifford A; Milagre, Humberto M S; Eberlin, Marcos N; Fiedler, Haidi D; Nome, Faruk

    2009-11-06

    Mixed micelles of cetyltrimethylammonium bromide (CTABr) or dodecyltrimethylammonium bromide (DTABr) and the alpha-nucleophile, lauryl hydroxamic acid (LHA) accelerate dephosphorylation of bis(2,4-dinitrophenyl)phosphate (BDNPP) over the pH range 4-10. With a 0.1 mole fraction of LHA in DTABr or CTABr, dephosphorylation of BDNPP is approximately 10(4)-fold faster than its spontaneous hydrolysis, and monoanionic LHA(-) is the reactive species. The results are consistent with a mechanism involving concurrent nucleophilic attack by hydroxamate ion (i) on the aromatic carbon, giving an intermediate that decomposes to undecylamine and 2,4-dinitrophenol, and (ii) at phosphorus, giving an unstable intermediate that undergoes a Lossen rearrangement yielding a series of derivatives including N,N-dialkylurea, undecylamine, undecyl isocyanate, and carbamyl hydroxamate.

  7. Glutamate and GABA-metabolizing enzymes in post-mortem cerebellum in Alzheimer's disease: phosphate-activated glutaminase and glutamic acid decarboxylase.

    Science.gov (United States)

    Burbaeva, G Sh; Boksha, I S; Tereshkina, E B; Savushkina, O K; Prokhorova, T A; Vorobyeva, E A

    2014-10-01

    Enzymes of glutamate and GABA metabolism in postmortem cerebellum from patients with Alzheimer's disease (AD) have not been comprehensively studied. The present work reports results of original comparative study on levels of phosphate-activated glutaminase (PAG) and glutamic acid decarboxylase isoenzymes (GAD65/67) in autopsied cerebellum samples from AD patients and matched controls (13 cases in each group) as well as summarizes published evidence for altered levels of PAG and GAD65/67 in AD brain. Altered (decreased) levels of these enzymes and changes in links between amounts of these enzymes and other glutamate-metabolizing enzymes (such as glutamate dehydrogenase and glutamine synthetase-like protein) in AD cerebella suggest significantly impaired glutamate and GABA metabolism in this brain region, which was previously regarded as not substantially involved in AD pathogenesis.

  8. New composite materials prepared by calcium phosphate precipitation in chitosan/collagen/hyaluronic acid sponge cross-linked by EDC/NHS.

    Science.gov (United States)

    Kaczmarek, B; Sionkowska, A; Kozlowska, J; Osyczka, A M

    2018-02-01

    Nowadays, fabrication of composite materials based on biopolymers is a rising field due to potential for bone repair and tissue engineering application. Blending of different biopolymers and incorporation of inorganic particles in the blend can lead to new materials with improved physicochemical properties and biocompatibility. In this work 3D porous structures called scaffolds based on chitosan, collagen and hyaluronic acid were obtained through the lyophilization process. Scaffolds were cross-linked by EDC/NHS. Infrared spectra for the materials were made, the percentage of swelling, scaffolds porosity and density, mechanical parameters, thermal stability were studied. Moreover, the scaffolds were used as matrixes for the calcium phosphate in situ precipitation. SEM images were taken and EDX analysis was carried out for calcium and phosphorous content determination in the scaffold. In addition, the adhesion and proliferation of human osteosarcoma SaOS-2 cells was examined on obtained scaffolds. The results showed that the properties of 3D composites cross-linked by EDC/NHS were altered after the addition of 1, 2 and 5% hyaluronic acid. Mechanical parameters, thermal stability and porosity of scaffolds were improved. Moreover, calcium and phosphorous were found in each kind of scaffold. SEM images showed that the precipitation was homogeneously carried in the whole volume of samples. Attachment of SaOS-2 cells to all modified materials was better compared to unmodified control and proliferation of these cells was markedly increased on scaffolds with precipitated calcium phosphate. Obtained materials can provide the support useful in tissue engineering and regenerative medicine. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Effect of moderately acidic pH on heat resistance of Clostridium sporogenes spores in phosphate buffer and in buffered pea puree.

    Science.gov (United States)

    Cameron, M S; Leonard, S J; Barrett, E L

    1980-01-01

    The effect of pH in the range 5.0 to 7.0 on the thermal destruction of spores of Clostridium sporogenes putrefactive anaerobe 3679 was examined by three methods: a capillary tube method in which spores were suspended in phosphate buffers, a thermoresistometer method in which spores were suspended in buffered pea puree adjusted to the same set of pH values, and a thermal death time can method in which spores were again suspended in buffered pea puree. The results indicated that increasing acidity is, in general, accompanied by decreasing heat resistance, although the pH effect was more pronounced at the higher than at the lower processing temperatures. Certain pH values appear to be critical, as they produced, in all three sets of experiments, effects which would not be predicted by the overall relationship between acidity and spore heat resistance. Differences between heat resistance in phosphate buffer as compared with that in pea puree adjusted to the same pH were also noted. D-values in buffer were found to be lower than those in pea puree, except at the highest temperatures coupled with the lowest pH values. The differences between buffer D-value and pea puree D-value were found to increase with increasing pH and with decreasing temperature. On the other hand, at all pH values examined, z-values determined in buffer were somewhat higher than those determined in pea puree adjusted to the same pH. PMID:7396485

  10. Thermodynamics of the nickel, cobalt and zinc removal from ethanolic solution by p-aminobenzoic acid intercalated on layered calcium phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Fernando M. de; Dias, Ana Paula B.; Babeto, Beatriz; Pelisson, Scarlet [Departamento de Química, Universidade Estadual de Maringá, Av. Colombo, 5790, 87020-900 Maringá, PR (Brazil); Lazarin, Angélica M., E-mail: amlazarin2@uem.br [Departamento de Química, Universidade Estadual de Maringá, Av. Colombo, 5790, 87020-900 Maringá, PR (Brazil); Sernaglia, Rosana L.; Andreotti, E.I.S. [Departamento de Química, Universidade Estadual de Maringá, Av. Colombo, 5790, 87020-900 Maringá, PR (Brazil); Airoldi, Claudio [Instituto de Química, Universidade Estadual de Campinas, Caixa Postal 6154, 13084-971 Campinas, São Paulo (Brazil)

    2014-08-10

    Graphical abstract: - Highlights: • Intercalation scheme for p-aminobenzoic acid inside the free inorganic host cavity. • The p-aminobenzoic acid is perpendicular orientation to the inorganic layer. • Forming a bilayer arrangement in the cavity. • The metallic ions were adsorbed on intercalated crystalline lamellar compound. - Abstract: Crystalline lamellar calcium phosphate retained p-aminobenzoic acid inside its cavity without leaching. The adsorption isotherms from ethanol gave the maximum adsorption capacities of 6.44, 3.34 and 1.62 mmol g{sup −1} for nickel, cobalt and zinc, respectively. The energetic effects caused by metallic cation interactions were determined through calorimetric titration at the solid/liquid interface and gave a net thermal effect that enabled enthalpy and equilibrium constant calculations. Complete thermodynamic data composed of exothermic enthalpy, negative free Gibbs energy and positive entropy conformed to a set of favorable cation/basic center interactions, to indicate that these materials could be useful tools to eliminate undesirable cations from ethanolic systems.

  11. Poly (amido amine) and nano-calcium phosphate bonding agent to remineralize tooth dentin in cyclic artificial saliva/lactic acid.

    Science.gov (United States)

    Liang, Kunneng; Weir, Michael D; Reynolds, Mark A; Zhou, Xuedong; Li, Jiyao; Xu, Hockin H K

    2017-03-01

    The objectives of this study were to develop a novel method to remineralize dentin lesions, and investigate the remineralization effects of poly (amido amine) (PAMAM) dendrimer plus a bonding agent with nanoparticles of amorphous calcium phosphate (NACP) in a cyclic artificial saliva/lactic acid environment for the first time. Dentin lesions were produced via phosphoric acid. Four groups were tested: (1) dentin control, (2) dentin with PAMAM, (3) dentin with NACP bonding agent, and (4) dentin with PAMAM plus NACP bonding agent. Specimens were treated with cyclic artificial saliva/lactic acid. The remineralized dentin was examined using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), hardness and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). NACP bonding agent yielded a dentin shear bond strength similar to commercial controls (Prime & Bond NT, Dentsply; Scotchbond Multi-purpose, 3M) (p>0.1). Increasing NACP in bonding agent from 0 to 40% did not affect bond strength. NACP bonding agent neutralized the acid and released Ca ions with concentrations of 4 to 20mmol/L, and P ions of 2 to 9mmol/L. PAMAM or NACP bonding agent alone achieved slight remineralization. The PAMAM+NACP group achieved the greatest dentin remineralization p0.1). In conclusion, superior remineralization of PAMAM+NACP bonding agent was demonstrated for the first time. PAMAM+NACP bonding agent induced dentin remineralization under acid challenge, when conventional remineralization methods such as PAMAM alone did not work well. The novel PAMAM+NACP bonding agent method is promising to improve the longevity of resin-dentin bonds, inhibit caries, and protect teeth. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Calcium phosphate/poly(D,L-lactic-co-glycolic acid) composite bone substitute materials: evaluation of temporal degradation and bone ingrowth in a rat critical-sized cranial defect.

    NARCIS (Netherlands)

    Watering, F.C.J. van de; Beucken, J.J.J.P van den; Walboomers, X.F.; Jansen, J.A.

    2012-01-01

    OBJECTIVES: The present study aimed to provide temporal information on material degradation and bone formation using composite (C) bone defect filler materials consisting of calcium phosphate cement (CaP) and poly(D,L-lactic-co-glycolic acid) (PLGA) microparticles (20 or 30 wt%) in rat

  13. Bone Healing Improvements Using Hyaluronic Acid and Hydroxyapatite/Beta-Tricalcium Phosphate in Combination: An Animal Study

    Directory of Open Access Journals (Sweden)

    Yen-Lan Chang

    2016-01-01

    Full Text Available The purpose of this study was to investigate whether the use of HLA as an aqueous binder of hydroxyapatite/beta-tricalcium phosphate (HA-βTCP particles can reduce the amount of bone graft needed and increase ease of handling in clinical situations. In this study, HA/βTCP was loaded in commercially available crosslinking HLA to form a novel HLA/HA-βTCP composite. Six New Zealand White rabbits (3.0–3.6 kg were used as test subjects. Four 6 mm defects were prepared in the parietal bone. The defects were filled with the HLA/HA-βTCP composite as well as HA-βTCP particle alone. New bone formation was analyzed by micro-CT and histomorphometry. Our results indicated that even when the HA-βTCP particle numbers were reduced, the regenerative effect on bone remained when the HLA existed. The bone volume density (BV/TV ratio of HLA/HA-βTCP samples was 1.7 times larger than that of the control sample at week 2. The new bone increasing ratio (NBIR of HLA/HA-βTCP samples was 1.78 times higher than the control group at week 2. In conclusion, HA-βTCP powder with HLA contributed to bone healing in rabbit calvarial bone defects. The addition of HLA to bone grafts not only promoted osteoconduction but also improved handling characteristics in clinical situations.

  14. Short term tolvaptan increases water intake and effectively decreases urinary calcium oxalate, calcium phosphate, and uric acid supersaturations

    Science.gov (United States)

    Cheungpasitporn, Wisit; Erickson, Stephen B.; Rule, Andrew D.; Enders, Felicity; Lieske, John C.

    2016-01-01

    Purpose Many patients cannot effectively increase water intake and urine volume to prevent urinary stones. Tolvaptan, a V2 receptor antagonist, blocks water reabsorption in the collecting duct and should reduce urinary supersaturation (SS) of stone forming solutes, but this has never been proven. Materials and Methods We conducted a double blind, randomized, placebo-controlled, crossover study in 21 adult calcium urinary stone formers stratified as majority calcium oxalate(CaOx, n=10) or calcium phosphate(CaP, n=11). Patients received tolvaptan 45 mg/day or placebo for 1 week, followed by a washout week and crossover to tolvaptan or placebo for week 3. A 24h urines was collected at the end of weeks 1 and 3. Results Tolvaptan vs. placebo decreased urinary osmolality (204±96 vs 529±213 mOsm/kg, P0.05 for all interactions). Conclusions Tolvaptan increases urine volume and decreases urinary SS in calcium stone formers. Further study is needed to determine if long term use of V2 receptor antagonists results in fewer stone events. PMID:26598423

  15. Sodium Phosphate

    Science.gov (United States)

    ... potassium in your blood; a high level of sodium or phosphate in your blood; colitis (inflammation of the large intestine) or other conditions that irritate your intestine; slow moving bowels; heart failure (condition in which the heart cannot pump blood through the body as well as it ...

  16. Dual functions of the trans-2-enoyl-CoA reductase TER in the sphingosine 1-phosphate metabolic pathway and in fatty acid elongation.

    Science.gov (United States)

    Wakashima, Takeshi; Abe, Kensuke; Kihara, Akio

    2014-09-05

    The sphingolipid metabolite sphingosine 1-phosphate (S1P) functions as a lipid mediator and as a key intermediate of the sole sphingolipid to glycerophospholipid metabolic pathway (S1P metabolic pathway). In this pathway, S1P is converted to palmitoyl-CoA through 4 reactions, then incorporated mainly into glycerophospholipids. Although most of the genes responsible for the S1P metabolic pathway have been identified, the gene encoding the trans-2-enoyl-CoA reductase, responsible for the saturation step (conversion of trans-2-hexadecenoyl-CoA to palmitoyl-CoA) remains unidentified. In the present study, we show that TER is the missing gene in mammals using analyses involving yeast cells, deleting the TER homolog TSC13, and TER-knockdown HeLa cells. TER is known to be involved in the production of very long-chain fatty acids (VLCFAs). A significant proportion of the saturated and monounsaturated VLCFAs are used for sphingolipid synthesis. Therefore, TER is involved in both the production of VLCFAs used in the fatty acid moiety of sphingolipids as well as in the degradation of the sphingosine moiety of sphingolipids via S1P. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Ethylene signalling is involved in regulation of phosphate starvation-induced gene expression and production of acid phosphatases and anthocyanin in Arabidopsis

    KAUST Repository

    Lei, Mingguang

    2010-11-30

    With the exception of root hair development, the role of the phytohormone ethylene is not clear in other aspects of plant responses to inorganic phosphate (Pi) starvation. The induction of AtPT2 was used as a marker to find novel signalling components involved in plant responses to Pi starvation. Using genetic and chemical approaches, we examined the role of ethylene in the regulation of plant responses to Pi starvation. hps2, an Arabidopsis mutant with enhanced sensitivity to Pi starvation, was identified and found to be a new allele of CTR1 that is a key negative regulator of ethylene responses. 1-aminocyclopropane-1-carboxylic acid (ACC), the precursor of ethylene, increases plant sensitivity to Pi starvation, whereas the ethylene perception inhibitor Ag+ suppresses this response. The Pi starvation-induced gene expression and acid phosphatase activity are also enhanced in the hps2 mutant, but suppressed in the ethylene-insensitive mutant ein2-5. By contrast, we found that ethylene signalling plays a negative role in Pi starvation-induced anthocyanin production. These findings extend the roles of ethylene in the regulation of plant responses to Pi starvation and will help us to gain a better understanding of the molecular mechanism underlying these responses. © 2010 The Authors. New Phytologist © 2010 New Phytologist Trust.

  18. Lactic acid and thermal treatments trigger the hydrolysis of myo-inositol hexakisphosphate and modify the abundance of lower myo-inositol phosphates in barley (Hordeum vulgare L..

    Directory of Open Access Journals (Sweden)

    Barbara U Metzler-Zebeli

    Full Text Available Barley is an important source of dietary minerals, but it also contains myo-inositol hexakisphosphate (InsP6 that lowers their absorption. This study evaluated the effects of increasing concentrations (0.5, 1, and 5%, vol/vol of lactic acid (LA, without or with an additional thermal treatment at 55°C (LA-H, on InsP6 hydrolysis, formation of lower phosphorylated myo-inositol phosphates, and changes in chemical composition of barley grain. Increasing LA concentrations and thermal treatment linearly reduced (P<0.001 InsP6-phosphate (InsP6-P by 0.5 to 1 g compared to the native barley. In particular, treating barley with 5% LA-H was the most efficient treatment to reduce the concentrations of InsP6-P, and stimulate the formation of lower phosphorylated myo-inositol phosphates such as myo-inositol tetraphosphate (InsP4 and myo-inositol pentaphosphates (InsP5. Also, LA and thermal treatment changed the abundance of InsP4 and InsP5 isomers with Ins(1,2,5,6P4 and Ins(1,2,3,4,5P5 as the dominating isomers with 5% LA, 1% LA-H and 5% LA-H treatment of barley, resembling to profiles found when microbial 6-phytase is applied. Treating barley with LA at room temperature (22°C increased the concentration of resistant starch and dietary fiber but lowered those of total starch and crude ash. Interestingly, total phosphorus (P was only reduced (P<0.05 in barley treated with LA-H but not after processing of barley with LA at room temperature. In conclusion, LA and LA-H treatment may be effective processing techniques to reduce InsP6 in cereals used in animal feeding with the highest degradation of InsP6 at 5% LA-H. Further in vivo studies are warranted to determine the actual intestinal P availability and to assess the impact of changes in nutrient composition of LA treated barley on animal performance.

  19. Role of phosphate in the central metabolism of two lactic acid bacteria - a comparative systems biology approach.

    NARCIS (Netherlands)

    Levering, J.; Musters, M.W.J.M.; Bekker, M..; Bellomo, D.; Fiedler, T.; de Vos, W.M.; Hugenholtz, J.; Kreikemeyer, b.; Kummer, U.; Teusink, B.

    2012-01-01

    Lactic acid-producing bacteria survive in distinct environments, but show common metabolic characteristics. Here we studied the dynamic interactions of the central metabolism in Lactococcus lactis, extensively used as a starter culture in the dairy industry, and Streptococcus pyogenes, a human

  20. Role of phosphate in the central metabolism of two lactic acid bacteria-a comparative systems biology approach

    NARCIS (Netherlands)

    Levering, J.; Musters, M.W.J.M.; Bekker, M.; Bellomo, D.; Fiedler, T.; Vos, de W.M.; Hugenholtz, F.; Kreikemeyer, B.; Kummer, U.; Teusink, B.

    2012-01-01

    Lactic acid-producing bacteria survive in distinct environments, but show common metabolic characteristics. Here we studied the dynamic interactions of the central metabolism in Lactococcus lactis, extensively used as a starter culture in the dairy industry, and Streptococcus pyogenes, a human

  1. 2-Aryl(pyrrolidin-4-yl)acetic acids are potent agonists of sphingosine-1-phosphate (S1P) receptors.

    Science.gov (United States)

    Yan, Lin; Budhu, Richard; Huo, Pei; Lynch, Christopher L; Hale, Jeffrey J; Mills, Sander G; Hajdu, Richard; Keohane, Carol A; Rosenbach, Mark J; Milligan, James A; Shei, Gan-Ju; Chrebet, Gary; Bergstrom, James; Card, Deborah; Mandala, Suzanne M

    2006-07-01

    A series of 2-aryl(pyrrolidin-4-yl)acetic acids were synthesized and their biological activities were evaluated as agonists of S1P receptors. These analogs were able to induce lowering of lymphocyte counts in the peripheral blood of mice and were found to have good overall pharmacokinetic properties in rat.

  2. EFFECT OF PHOSPHATE ON NODULE PRIMORDIA OF SOYBEAN (Glycine max Merrill IN ACID SOILS IN RHIZOTRON EXPERIMENTS

    Directory of Open Access Journals (Sweden)

    Setiyo Hadi Waluyo

    2016-10-01

    Full Text Available To clarify whether P had a direct or indirect effect on the nodulation  process of soybean grown in acid soils from Sitiung, West Sumatra, Indonesia, a series of rhizotron experiments, with special attention given to formation of nodule primordia, was conducted at Laboratory of  Microbiology, Wageningen University in 1998-2000. It was shown that Ca and P were essential nutrients for root growth, nodule formation, and growth of soybean in the acid soils (Oxisols. Ca increased root growth, number of nodule primordia, nodules, and growth of the soybean plant. This positive effect of Ca was increased considerably by the application of P. Ca and P have a synergistic effect on biological nitrogen fixation (BNF of soybean in acid soils. Ca is important for the establishment of nodules, whilst P is essential for the development and function of the formed nodules. P increased number of nodule primordia, thus it also has an important role in the initiation of nodule formation. From this study, it can be concluded that Ca and P are the most limiting nutrients for BNF of soybean in the acid soils of Sitiung, West Sumatra, Indonesia.

  3. Split-dose Bowel Preparation for Colonoscopy: 2 Liters Polyethylene Glycol with Ascorbic Acid versus Sodium Picosulfate versus Oral Sodium Phosphate Tablets.

    Science.gov (United States)

    Lee, Seok Won; Bang, Chang Seok; Park, Tae Young; Suk, Ki Tae; Baik, Gwang Ho; Kim, Dong Joon

    2017-08-25

    Adequate bowel preparation is an essential factor affecting the visibility of colonic mucosa and safety of related therapeutic interventions. The aim of this study was to assess the efficacy, tolerability, and safety of three bowel preparation agents -2 L polyethylene glycol with ascorbic acid (PEGA), sodium picosulfate magnesium citrate (SPMC), and oral sodium phosphate tablet (NaP)- for morning colonoscopy. Here, we analyzed the medical records of patients who had taken bowel preparation agents using the split-dose method and undergone colonoscopy in a single hospital. The efficacy of bowel preparation agents was evaluated using the Ottawa bowel preparation assessment tool. The safety and tolerability of the agents were assessed by measuring the renal function and electrolytes prior to and after the procedure as well as by assessing the self-reported questionnaire. Of the 365 patients (PEGA:163, SPMC: 93, NaP: 109), 98.6% ingested more than 90% of the agents. NaP showed an inferior cleansing efficacy, and serum phosphate elevation was significantly higher in the NaP group. However, the satisfaction score was lowest in the PEGA group. Age (odds ratio [OR] 0.96, 95% confidence interval [CI] 0.92-0.99, p=0.04) and preparation agents (OR of PEGA versus NaP 5.0, 95% CI 2.28-10.97, p<0.001) (OR of SPMC versus NaP 2.73, 95% CI 1.22-6.08, p=0.01) were independently associated with bowel preparation success. According to our analysis, NaP showed an inferior cleansing efficacy compared with PEGA and SPMC, which may be attributed to the complex administration method and lower water intake. However, large-volume ingestion remains unsatisfactory for patients. Detailed bowel preparation instructions could enhance bowel cleansing efficacy.

  4. Lactic acid and thermal treatments trigger the hydrolysis of myo-inositol hexakisphosphate and modify the abundance of lower myo-inositol phosphates in barley (Hordeum vulgare L.).

    Science.gov (United States)

    Metzler-Zebeli, Barbara U; Deckardt, Kathrin; Schollenberger, Margit; Rodehutscord, Markus; Zebeli, Qendrim

    2014-01-01

    Barley is an important source of dietary minerals, but it also contains myo-inositol hexakisphosphate (InsP6) that lowers their absorption. This study evaluated the effects of increasing concentrations (0.5, 1, and 5%, vol/vol) of lactic acid (LA), without or with an additional thermal treatment at 55°C (LA-H), on InsP6 hydrolysis, formation of lower phosphorylated myo-inositol phosphates, and changes in chemical composition of barley grain. Increasing LA concentrations and thermal treatment linearly reduced (Pbarley. In particular, treating barley with 5% LA-H was the most efficient treatment to reduce the concentrations of InsP6-P, and stimulate the formation of lower phosphorylated myo-inositol phosphates such as myo-inositol tetraphosphate (InsP4) and myo-inositol pentaphosphates (InsP5). Also, LA and thermal treatment changed the abundance of InsP4 and InsP5 isomers with Ins(1,2,5,6)P4 and Ins(1,2,3,4,5)P5 as the dominating isomers with 5% LA, 1% LA-H and 5% LA-H treatment of barley, resembling to profiles found when microbial 6-phytase is applied. Treating barley with LA at room temperature (22°C) increased the concentration of resistant starch and dietary fiber but lowered those of total starch and crude ash. Interestingly, total phosphorus (P) was only reduced (Pbarley treated with LA-H but not after processing of barley with LA at room temperature. In conclusion, LA and LA-H treatment may be effective processing techniques to reduce InsP6 in cereals used in animal feeding with the highest degradation of InsP6 at 5% LA-H. Further in vivo studies are warranted to determine the actual intestinal P availability and to assess the impact of changes in nutrient composition of LA treated barley on animal performance.

  5. Vibrational analysis of nucleic acids. I. The phosphodiester group in dimethyl phosphate model compounds: (CH3O)2PO2-, (CD3O)2PO2-, and (13CH3O)2PO2-.

    OpenAIRE

    Guan, Y.; Wurrey, C.J.; Thomas Jr, G.J.

    1994-01-01

    Normal coordinate analyses and vibrational assignments are presented for the dimethyl phosphate anion [(CH3O)2PO2-] and its deuteriomethyl [(CD3O)2PO2-] and carbon-13 [(13CH3O)2PO2-] derivatives in the gauche-gauche conformation. The dimethyl phosphate anion, which is the simplest model for the nucleic acid phosphodiester moiety, exhibits many of the spectral complexities of DNA and RNA and has previously resisted a complete and consistent vibrational analysis. In the present study we make us...

  6. Formulation and evaluation of hydrous and anhydrous skin whitening products containing sodium ascorbyl phosphate and kojic acid dipalmitate / Marike Ganz

    OpenAIRE

    Ganz, Marike

    2006-01-01

    In Asia skin lightening products have grown to be the best selling skin care products, whereas in the Western hemisphere, including Europe and North America, the main demand is for the treatment of age spots and skin even toning. For African and Asian women, skin lightening is part of their culture, as lighter skin signifies increased wealth and social status. It is believed that blending vitamin C, or its derivates, with kojic acid, or its esters, could synergistically inhibit...

  7. High dose folic acid pre-treatment blunts cardiac dysfunction during ischemia coupled to maintenance of high energy phosphates and reduces post-reperfusion injury

    Science.gov (United States)

    Moens, An L.; Champion, Hunter C.; Claeys, Marc J.; Tavazzi, Barbara; Kaminki, Pawel M.; Wolin, Michael S.; Borgonjon, Dirk; Van Nassauw, Luc; Haile, Azeb; Zviman, Muz; Bedja, Djahida; Wuyts, Floris L.; Elsaesser, Rebecca S.; Cos, Paul; Gabrielson, Kathy L.; Lazzarino, Giuseppe; Paolocci, Nazareno; Timmermans, Jean-Pierre; Vrints, Christiaan J.; Kass, David A.

    2008-01-01

    Background The B-vitamin folic acid (FA) is important to mitochondrial protein and nucleic acid synthesis, is an anti-oxidant, and enhances nitric oxide synthase activity. Here, we tested whether FA reduces myocardial ischemic dysfunction and post-reperfusion injury. Methods Wistar rats were pretreated with either FA (10mg/d) or placebo for 1-wk, and then underwent in vivo transient left coronary artery occlusion for 30min with or without 90min reperfusion (total:n=131; sub-groups used for various analyses). FA (4.5•10-6M i.c) pretreatment and global ischemia/reperfusion (30 min/30min), was also performed in vitro (n=28). Results After 30min ischemia, global function declined more in controls than FA-pretreated rats (ΔdP/dtmax -878±586 mmHg/s vs. placebo -1956±351 mmHg/s, p=0.03), and regional thickening was better preserved (37.3±5.3% vs. 5.1±0.6%-placebo, p=0.004). Anterior-wall perfusion fell similarly (-78.4±9.3% vs. -71.2±13.8%-placebo at 30 min); yet myocardial high energy phosphates ATP and ADP reduced by ischemia in controls were better preserved by FA-pretreatment (e.g. ATP: control: 2740±58; ischemia: 947±55; ischemia+FA: 1332±101 nmol/g, p=0.02). Basal oxypurines (xanthine, hypoxanthine, and urate) rose with FA-pretreatment, but increased less during ischemia than in controls. Ischemic superoxide generation declined (3124±280 FA vs. 5898±474 placebo, cpm/mg, p=0.001). After reperfusion, FA-treated hearts had smaller infarcts (3.8±1.2% vs 60.3±4.1%-placebo area at risk, p<0.002), less contraction band necrosis, TUNEL-positivity, superoxide, and nitric oxide synthase uncoupling. Infarct size declined similarly with 1 mg/d FA as well. Conclusion FA-pretreatment blunts myocardial dysfunction during ischemia, and ameliorates post-reperfusion injury. This is coupled to preservation of high energy phosphates, reducing subsequent ROS-generation, eNOS-uncoupling and post-reperfusion cell death. PMID:18362233

  8. High-dose folic acid pretreatment blunts cardiac dysfunction during ischemia coupled to maintenance of high-energy phosphates and reduces postreperfusion injury.

    Science.gov (United States)

    Moens, An L; Champion, Hunter C; Claeys, Marc J; Tavazzi, Barbara; Kaminski, Pawel M; Wolin, Michael S; Borgonjon, Dirk J; Van Nassauw, Luc; Haile, Azeb; Zviman, Muz; Bedja, Djahida; Wuyts, Floris L; Elsaesser, Rebecca S; Cos, Paul; Gabrielson, Kathy L; Lazzarino, Giuseppe; Paolocci, Nazareno; Timmermans, Jean-Pierre; Vrints, Christiaan J; Kass, David A

    2008-04-08

    The B vitamin folic acid (FA) is important to mitochondrial protein and nucleic acid synthesis, is an antioxidant, and enhances nitric oxide synthase activity. Here, we tested whether FA reduces myocardial ischemic dysfunction and postreperfusion injury. Wistar rats were pretreated with either FA (10 mg/d) or placebo for 1 week and then underwent in vivo transient left coronary artery occlusion for 30 minutes with or without 90 minutes of reperfusion (total n=131; subgroups used for various analyses). FA (4.5x10(-6) mol/L i.c.) pretreatment and global ischemia/reperfusion (30 minutes/30 minutes) also were performed in vitro (n=28). After 30 minutes of ischemia, global function declined more in controls than in FA-pretreated rats (Delta dP/dtmax, -878+/-586 versus -1956+/-351 mm Hg/s placebo; P=0.03), and regional thickening was better preserved (37.3+/-5.3% versus 5.1+/-0.6% placebo; P=0.004). Anterior wall perfusion fell similarly (-78.4+/-9.3% versus -71.2+/-13.8% placebo at 30 minutes), yet myocardial high-energy phosphates ATP and ADP reduced by ischemia in controls were better preserved by FA pretreatment (ATP: control, 2740+/-58 nmol/g; ischemia, 947+/-55 nmol/g; ischemia plus FA, 1332+/-101 nmol/g; P=0.02). Basal oxypurines (xanthine, hypoxanthine, and urate) rose with FA pretreatment but increased less during ischemia than in controls. Ischemic superoxide generation declined (3124+/-280 cpm/mg FA versus 5898+/-474 cpm/mg placebo; P=0.001). After reperfusion, FA-treated hearts had smaller infarcts (3.8+/-1.2% versus 60.3+/-4.1% placebo area at risk; P<0.002) and less contraction band necrosis, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling positivity, superoxide, and nitric oxide synthase uncoupling. Infarct size declined similarly with 1 mg/d FA. FA pretreatment blunts myocardial dysfunction during ischemia and ameliorates postreperfusion injury. This is coupled to preservation of high-energy phosphates, reducing subsequent reactive

  9. Optimizing Available Phosphorus in Calcareous Soils Fertilized with Diammonium Phosphate and Phosphoric Acid Using Freundlich Adsorption Isotherm

    Directory of Open Access Journals (Sweden)

    Asif Naeem

    2013-01-01

    Full Text Available In calcareous soils, phosphorus (P retention and immobilization take place due to precipitation and adsorption. Since soil pH is considered a major soil variable affecting the P sorption, an acidic P fertilizer could result in low P adsorption compared to alkaline one. Therefore, P adsorption from DAP and phosphoric acid (PA required to produce desired soil solution P concentration was estimated using Freundlich sorption isotherms. Two soils from Faisalabad and T. T. Singh districts were spiked with 0, 10, and 20 % for 15 days. Freundlich adsorption isotherms ( were constructed, and theoretical doses of PA and DAP to develop a desired soil solution P level (i.e., 0.20 mg L−1 were calculated. It was observed that P adsorption in soil increased with . Moreover, at all the levels of , P adsorption from PA was lower compared to that from DAP in both the soils. Consequently, lesser quantity of PA was required to produce desired solution P, 0.2 mg L−1, compared to DAP. However, extrapolating the developed relationship between soil contents and quantity of fertilizer to other similar textured soils needs confirmation.

  10. Optimizing available phosphorus in calcareous soils fertilized with diammonium phosphate and phosphoric acid using Freundlich adsorption isotherm.

    Science.gov (United States)

    Naeem, Asif; Akhtar, Muhammad; Ahmad, Waqar

    2013-01-01

    In calcareous soils, phosphorus (P) retention and immobilization take place due to precipitation and adsorption. Since soil pH is considered a major soil variable affecting the P sorption, an acidic P fertilizer could result in low P adsorption compared to alkaline one. Therefore, P adsorption from DAP and phosphoric acid (PA) required to produce desired soil solution P concentration was estimated using Freundlich sorption isotherms. Two soils from Faisalabad and T. T. Singh districts were spiked with 0, 10, and 20 % CaCO3 for 15 days. Freundlich adsorption isotherms (P = aC(b/a)) were constructed, and theoretical doses of PA and DAP to develop a desired soil solution P level (i.e., 0.20 mg L(-1)) were calculated. It was observed that P adsorption in soil increased with CaCO3. Moreover, at all the levels of CaCO3, P adsorption from PA was lower compared to that from DAP in both the soils. Consequently, lesser quantity of PA was required to produce desired solution P, 0.2 mg L(-1), compared to DAP. However, extrapolating the developed relationship between soil CaCO3 contents and quantity of fertilizer to other similar textured soils needs confirmation.

  11. Iodine 125-phenylpentadecanoic acid and its beta-methyl substitute metabolism in cultured mouse embryonal myocytes; Iodine-labelled fatty acids as tracers of myocardial high energy phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Okano, Mitsuji; Ohsuzu, Fumitaka; Sakata, Nobuhiro; Katsushika, Shuuichi; Nakamura, Haruo (National Defense Medical Coll., Tokorozawa, Saitama (Japan)); Ishida, Hideyuki; Aosaki, Noboru

    1993-02-01

    Iodine-labelled fatty acids have been proposed as new tracers of cardiac metabolisms. However, it is not clear how these tracers would reflect the intracellular metabolism. Therefore, we measured the uptake and release of iodine 125-labelled phenylpentadecanoic acid (IPPA), its [beta]-methyl substitute (BMIPP) and [sup 201]Tl in cultured myocytes of mouse embryos, and compared these values to intracellular adenosine triphosphate (ATP) content after metabolic inhibitions of oxidative phosphorylation by sodium cyanide (CN), glycolysis by 2-deoxyglucose (2-DG) or fatty acid [beta]-oxidation by lactate. The uptake and release of BMIPP was not changed by any inhibitors suggesting BMIPP would not be metabolized in the myocytes. The uptake of IPPA was significantly reduced by 2DG and 60-80% of IPPA was metabolized to hydrophilic catabolites. The correlation of BMIPP and IPPA uptake to intracellular ATP content were high (r=0.89, p<0.05; r=0.86, p<0.1), but there was poor correlation of [sup 201]Tl to ATP values (r=0.53, n.s.). These results suggested that iodine-labelled fatty acids could be used as better tracers of myocardial metabolism than [sup 201]Tl. (author).

  12. Phosphate cellulose with metaphosphoric acid for dye removal; Celulose fosfatada com acido metafosforico para remocao de corantes

    Energy Technology Data Exchange (ETDEWEB)

    Silva, S.C.C.; Silva, F.C.; Lima, L.C.B.; Santos, M.R.M.C.; Osajima, J.A.; Silva Filho, E.C. da, E-mail: briciaquimica@hotmail.com [Universidade Federal do Piaui (UFPI), Teresina, PI (Brazil). Programa de Pos-Graduacao em Ciencia dos Materiais. Laboratorio Interdisciplinar de Materiais Avancados; Silva, M.M.F. [Instituto Federal de Educacao, Ciencia e Tecnologia do Rio Grande do Norte (IFRN), RN (Brazil)

    2014-07-01

    The chemical modification of cellulose is a suitable method used for producing value-added products, making them more efficient and selective for certain applications such as adsorption of dye. Thus the aim of this study was to modify the natural cellulose with metaphosphoric acid, characterized it through the techniques of FTIR and {sup 31}P NMR and applies it in the adsorption of brilliant green dye, evaluating the kinetic models of pseudo first-order and pseudo second-order and the theoretical models of the Langmuir, Freundlich and Temkin isotherms. The characterizations demonstrated the effectiveness of the modification, the maximum adsorption capacity was 150.0 mg g-1, adjusting better to the kinetic model of pseudo-second order and the theoretical model of Temkin, with the adsorbent showing efficient for removal of brilliant green dye. (author)

  13. In vitro test and application for guided bone regeneration of {beta}-tricalcium phosphate / poly-(lactide-glycolic acid-{epsilon}-caprolactone) composites

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, M.; Tanaka, J. [National Inst. for Research in Inorganic Materials, Tsukuba (Japan); Koyama, Y.; Takakuda, K.; Miyairi, H. [Tokyo Medical and Dental Univ. (Japan). Inst. of Biomaterials and Bioengineering

    2001-07-01

    In order to realize easy handling films, novel composites of {beta}-tricalcium phosphate (TCP) and poly-(lactide-glycolic acid-{epsilon}-caprolactone) (PLGC) having a softening temperature of about 40 C were prepared by a heat-kneading method. The composite prepared could be easily formed into a cylindrical membrane at 40 C, and its tensile strength was greater than that of a pure PLGC. From Fourier-transformed infrared spectroscopy, it was shown that the chemical interaction formed between TCP and PLGC. Physiological saline soaking test indicated that TCP inhibited hydrolysis of PLGC by auto-controlling saline pH, resulting in almost constant tensile strength. Mandibular 2-wall bone defects 2 x 1 x 1 cm{sup 3} in size and tibia fully defects 2 cm in length of beagles were filled with new bone 12 weeks after guided bone regeneration (GBR) operation using the composite membrane, although a pure PLGC membrane could not repair such defects. The composite membrane was useful for the GBR membrane. (orig.)

  14. Mechanism of sphingosine 1-phosphate- and lysophosphatidic acid-induced up-regulation of adhesion molecules and eosinophil chemoattractant in nerve cells.

    Science.gov (United States)

    Costello, Richard W; Maloney, Michael; Atiyeh, Mazin; Gleich, Gerald; Walsh, Marie-Therese

    2011-01-01

    The lysophospholipids sphingosine 1-phosphate (S1P) and lysophosphatidic acid (LPA) act via G-protein coupled receptors S1P(1-5) and LPA(1-3) respectively, and are implicated in allergy. Eosinophils accumulate at innervating cholinergic nerves in asthma and adhere to nerve cells via intercellular adhesion molecule-1 (ICAM-1). IMR-32 neuroblastoma cells were used as an in vitro cholinergic nerve cell model. The G(i) coupled receptors S1P(1), S1P(3), LPA(1), LPA(2) and LPA(3) were expressed on IMR-32 cells. Both S1P and LPA induced ERK phosphorylation and ERK- and G(i)-dependent up-regulation of ICAM-1 expression, with differing time courses. LPA also induced ERK- and G(i)-dependent up-regulation of the eosinophil chemoattractant, CCL-26. The eosinophil granule protein eosinophil peroxidase (EPO) induced ERK-dependent up-regulation of transcription of S1P(1), LPA(1), LPA(2) and LPA(3), providing the situation whereby eosinophil granule proteins may enhance S1P- and/or LPA- induced eosinophil accumulation at nerve cells in allergic conditions.

  15. Mechanism of sphingosine 1-phosphate- and lysophosphatidic Acid-induced up-regulation of adhesion molecules and eosinophil chemoattractant in nerve cells.

    LENUS (Irish Health Repository)

    Costello, Richard W

    2012-02-01

    The lysophospholipids sphingosine 1-phosphate (S1P) and lysophosphatidic acid (LPA) act via G-protein coupled receptors S1P(1-5) and LPA(1-3) respectively, and are implicated in allergy. Eosinophils accumulate at innervating cholinergic nerves in asthma and adhere to nerve cells via intercellular adhesion molecule-1 (ICAM-1). IMR-32 neuroblastoma cells were used as an in vitro cholinergic nerve cell model. The G(i) coupled receptors S1P(1), S1P(3), LPA(1), LPA(2) and LPA(3) were expressed on IMR-32 cells. Both S1P and LPA induced ERK phosphorylation and ERK- and G(i)-dependent up-regulation of ICAM-1 expression, with differing time courses. LPA also induced ERK- and G(i)-dependent up-regulation of the eosinophil chemoattractant, CCL-26. The eosinophil granule protein eosinophil peroxidase (EPO) induced ERK-dependent up-regulation of transcription of S1P(1), LPA(1), LPA(2) and LPA(3), providing the situation whereby eosinophil granule proteins may enhance S1P- and\\/or LPA- induced eosinophil accumulation at nerve cells in allergic conditions.

  16. Mechanism of sphingosine 1-phosphate- and lysophosphatidic Acid-induced up-regulation of adhesion molecules and eosinophil chemoattractant in nerve cells.

    LENUS (Irish Health Repository)

    Costello, Richard W

    2011-05-01

    The lysophospholipids sphingosine 1-phosphate (S1P) and lysophosphatidic acid (LPA) act via G-protein coupled receptors S1P(1-5) and LPA(1-3) respectively, and are implicated in allergy. Eosinophils accumulate at innervating cholinergic nerves in asthma and adhere to nerve cells via intercellular adhesion molecule-1 (ICAM-1). IMR-32 neuroblastoma cells were used as an in vitro cholinergic nerve cell model. The G(i) coupled receptors S1P(1), S1P(3), LPA(1), LPA(2) and LPA(3) were expressed on IMR-32 cells. Both S1P and LPA induced ERK phosphorylation and ERK- and G(i)-dependent up-regulation of ICAM-1 expression, with differing time courses. LPA also induced ERK- and G(i)-dependent up-regulation of the eosinophil chemoattractant, CCL-26. The eosinophil granule protein eosinophil peroxidase (EPO) induced ERK-dependent up-regulation of transcription of S1P(1), LPA(1), LPA(2) and LPA(3), providing the situation whereby eosinophil granule proteins may enhance S1P- and\\/or LPA- induced eosinophil accumulation at nerve cells in allergic conditions.

  17. Therapeutic designed poly (lactic-co-glycolic acid) cylindrical oseltamivir phosphate-loaded implants impede tumor neovascularization, growth and metastasis in mouse model of human pancreatic carcinoma

    Science.gov (United States)

    Hrynyk, Michael; Ellis, Jordon P; Haxho, Fiona; Allison, Stephanie; Steele, Joseph AM; Abdulkhalek, Samar; Neufeld, Ronald J; Szewczuk, Myron R

    2015-01-01

    Poly (lactic-co-glycolic acid) (PLGA) copolymers have been extensively used in cancer research. PLGA can be chemically engineered for conjugation or encapsulation of drugs in a particle formulation. We reported that oseltamivir phosphate (OP) treatment of human pancreatic tumor-bearing mice disrupted the tumor vasculature with daily injections. Here, the controlled release of OP from a biodegradable PLGA cylinder (PLGA-OP) implanted at tumor site was investigated for its role in limiting tumor neovascularization, growth, and metastasis. PLGA-OP cylinders over 30 days in vitro indicated 20%–25% release profiles within 48 hours followed by a continuous metronomic low dose release of 30%–50% OP for an additional 16 days. All OP was released by day 30. Surgically implanted PLGA-OP containing 20 mg OP and blank PLGA cylinders at the tumor site of heterotopic xenografts of human pancreatic PANC1 tumors in RAGxCγ double mutant mice impeded tumor neovascularization, growth rate, and spread to the liver and lungs compared with the untreated cohort. Xenograft tumors from PLGA and PLGA-OP-treated cohorts expressed significant higher levels of human E-cadherin with concomitant reduced N-cadherin and host CD31+ endothelial cells compared with the untreated cohort. These results clearly indicate that OP delivered from PLGA cylinders surgically implanted at the site of the solid tumor show promise as an effective treatment therapy for cancer. PMID:26309402

  18. Fabrication of Blended Polycaprolactone/Poly (Lactic-Co-Glycolic Acid)/β-Tricalcium Phosphate Thin Membrane Using Solid Freeform Fabrication Technology for Guided Bone Regeneration

    Science.gov (United States)

    Shim, Jin-Hyung; Huh, Jung-Bo; Park, Ju Young; Jeon, Young-Chan; Kang, Seong Soo; Kim, Jong Young; Rhie, Jong-Won

    2013-01-01

    This study developed a bioabsorbable-guided bone regeneration membrane made of blended polycaprolactone (PCL), poly(lactic-co-glycolic acid) (PLGA), and beta-tricalcium phosphate (β-TCP) using solid freeform fabrication (SFF) technology. The chemical and physical properties of the membrane were evaluated using field emission scanning electron microscopy, energy dispersive spectroscopy, and a tensile test. In vitro cell activity assays revealed that the adhesion, proliferation, and osteogenic differentiation of seeded adipose-derived stem cells (ADSCs) were significantly promoted by the PCL/PLGA/β-TCP membranes compared with PCL/PLGA membranes. When the PCL/PLGA and PCL/PLGA/β-TCP membranes were implanted on rabbit calvaria bone defects without ADSCs, microcomputed tomography and histological analyses confirmed that the SFF-based PCL/PLGA/β-TCP membranes greatly increased bone formation without the need for bone substitute materials. Moreover, tight integration, which helps to prevent exposure of the membrane, between both membranes and the soft tissues was clearly observed histologically. The SFF-based PCL/PLGA and PCL/PLGA/β-TCP membranes retained their mechanical stability for up to 8 weeks without significant collapse. Furthermore, PCL/PLGA/β-TCP underwent adequate degradation without a significant immune response at 8 weeks. PMID:22934667

  19. Study of pure and L-tartaric acid doped ammonium dihydrogen phosphate single crystals: A novel nonlinear optical non-centrosymmetric crystal

    Energy Technology Data Exchange (ETDEWEB)

    Hasmuddin, Mohd, E-mail: mhasmu@gmail.com [Crystal Growth Laboratory, Dept. of Physics, Jamia Millia Islamia, New Delhi 110 025 (India); Singh, Preeti [Crystal Growth Laboratory, Dept. of Physics, Jamia Millia Islamia, New Delhi 110 025 (India); Shkir, Mohd [Crystal Growth Laboratory, Dept. of Physics, Jamia Millia Islamia, New Delhi 110 025 (India); Department of Physics, School of Science, King Khalid University, P.O. Box. 9004, Abha 61413 (Saudi Arabia); Abdullah, M.M. [Crystal Growth Laboratory, Dept. of Physics, Jamia Millia Islamia, New Delhi 110 025 (India); Promising Centre for Sensors and Electronic Devices (PCSED), Department of Physics, College of Science and Arts, Najran University, P.O. Box 1988, Najran 11001 (Saudi Arabia); Vijayan, N. [CSIR – National Physical Laboratory, Dr. K. S. Krishnan Road, New Delhi 110 012 (India); Ganesh, V. [Department of Physics, Kakatiya University, Warangal, Andhra Pradesh 506009 (India); Wahab, M.A., E-mail: mwahab@jmi.ac.in [Crystal Growth Laboratory, Dept. of Physics, Jamia Millia Islamia, New Delhi 110 025 (India)

    2014-04-01

    Single crystals of pure and L-tartaric acid (LTA) C{sub 4}H{sub 6}O{sub 6} doped ammonium dihydrogen phosphate (ADP) (NH{sub 4}) H{sub 2}PO{sub 4} were grown by slow evaporation solution technique (SEST) at ambient conditions. Powder X-ray diffraction (PXRD) analysis was carried out to confirm the crystal structure and no additional phase was observed due to doping except a systematic variation in peak intensities. Fourier transform infrared spectral analysis was done to examine the presence of various functional groups in the grown crystals. UV–VIS–NIR spectroscopic analysis was carried out to see the change in optical transparency of pure ADP and crystals due to LTA with different doping concentrations. Second harmonic generation (SHG) efficiency measurement was done to examine the enhancement in the nonlinear optical characteristics of the grown crystals. The effect of LTA dopant on crystal morphology, thermal and mechanical properties of ADP have also been presented in this paper. The above studies reveal the effect of incorporation of LTA into the lattice of ADP crystals. - Highlights: • LTA doped ADP crystals were grown for the first time. • Optical transmission was found to be higher at 1 mol% LTA doping. • SHG was found to be enhanced nonlinearly due to doping. • Thermal stability was found to higher at 1 mol% LTA doping. • Hardness was found to be increases with doping.

  20. On the Use of Molecular Weight Cutoff Cassettes to Measure Dynamic Relaxivity of Novel Gadolinium Contrast Agents: Example Using Hyaluronic Acid Polymer Complexes in Phosphate-Buffered Saline

    Directory of Open Access Journals (Sweden)

    Nima Kasraie

    2011-01-01

    Full Text Available The aims of this study were to determine whether standard extracellular contrast agents of Gd(III ions in combination with a polymeric entity susceptible to hydrolytic degradation over a finite period of time, such as Hyaluronic Acid (HA, have sufficient vascular residence time to obtain comparable vascular imaging to current conventional compounds and to obtain sufficient data to show proof of concept that HA with Gd-DTPA ligands could be useful as vascular imaging agents. We assessed the dynamic relaxivity of the HA bound DTPA compounds using a custom-made phantom, as well as relaxation rates at 10.72 MHz with concentrations ranging between 0.09 and 7.96 mM in phosphate-buffered saline. Linear dependences of static longitudinal relaxation rate (R1 on concentration were found for most measured samples, and the HA samples continued to produce high signal strength after 24 hours after injection into a dialysis cassette at 3T, showing superior dynamic relaxivity values compared to conventional contrast media such as Gd-DTPA-BMA.

  1. A controlled release of antibiotics from calcium phosphate-coated poly(lactic-co-glycolic acid) particles and their in vitro efficacy against Staphylococcus aureus biofilm.

    Science.gov (United States)

    Bastari, Kelsen; Arshath, Mohamed; Ng, Zhi Hui Melissa; Chia, Jia Hua; Yow, Zhi Xian Daniel; Sana, Barindra; Tan, Meng Fong Cherine; Lim, Sierin; Loo, Say Chye Joachim

    2014-03-01

    Ceramic-polymer hybrid particles, intended for osteomyelitis treatment, were fabricated by preparing poly(lactic-co-glycolic acid) particles through an emulsion solvent evaporation technique, followed by calcium phosphate (CaP) coating via a surface adsorption-nucleation method. The presence of CaP coating on the surface of the particles was confirmed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. Subsequently, two antibiotics for treating bone infection, nafcillin (hydrophilic) and levofloxacin (amphiphilic), were loaded into these hybrid particles and their in vitro drug release studies were investigated. The CaP coating was shown to reduce burst release, while providing sustained release of the antibiotics for up to 4 weeks. In vitro bacterial study against Staphylococcus aureus demonstrated the capability of these antibiotic-loaded hybrid particles to inhibit biofilm formation as well as deteriorate established biofilm, making this hybrid system a potential candidate for further investigation for osteomyelitis treatment.

  2. NMR studies of protonation and hydrogen bond states of internal aldimines of pyridoxal 5'-phosphate acid-base in alanine racemase, aspartate aminotransferase, and poly-L-lysine.

    Science.gov (United States)

    Chan-Huot, Monique; Dos, Alexandra; Zander, Reinhard; Sharif, Shasad; Tolstoy, Peter M; Compton, Shara; Fogle, Emily; Toney, Michael D; Shenderovich, Ilya; Denisov, Gleb S; Limbach, Hans-Heinrich

    2013-12-04

    Using (15)N solid-state NMR, we have studied protonation and H-bonded states of the cofactor pyridoxal 5'-phosphate (PLP) linked as an internal aldimine in alanine racemase (AlaR), aspartate aminotransferase (AspAT), and poly-L-lysine. Protonation of the pyridine nitrogen of PLP and the coupled proton transfer from the phenolic oxygen (enolimine form) to the aldimine nitrogen (ketoenamine form) is often considered to be a prerequisite to the initial step (transimination) of the enzyme-catalyzed reaction. Indeed, using (15)N NMR and H-bond correlations in AspAT, we observe a strong aspartate-pyridine nitrogen H-bond with H located on nitrogen. After hydration, this hydrogen bond is maintained. By contrast, in the case of solid lyophilized AlaR, we find that the pyridine nitrogen is neither protonated nor hydrogen bonded to the proximal arginine side chain. However, hydration establishes a weak hydrogen bond to pyridine. To clarify how AlaR is activated, we performed (13)C and (15)N solid-state NMR experiments on isotopically labeled PLP aldimines formed by lyophilization with poly-L-lysine. In the dry solid, only the enolimine tautomer is observed. However, a fast reversible proton transfer involving the ketoenamine tautomer is observed after treatment with either gaseous water or gaseous dry HCl. Hydrolysis requires the action of both water and HCl. The formation of an external aldimine with aspartic acid at pH 9 also produces the ketoenamine form stabilized by interaction with a second aspartic acid, probably via a H-bond to the phenolic oxygen. We postulate that O-protonation is an effectual mechanism for the activation of PLP, as is N-protonation, and that enzymes that are incapable of N-protonation employ this mechanism.

  3. A descriptive study of skeletal muscle metabolism in critically ill patients: free amino acids, energy-rich phosphates, protein, nucleic acids, fat, water, and electrolytes.

    Science.gov (United States)

    Gamrin, L; Essén, P; Forsberg, A M; Hultman, E; Wernerman, J

    1996-04-01

    To characterize biochemical changes in skeletal muscle in critically ill patients. Survey of critically ill patients. Intensive care unit (ICU) at a university hospital. Critically ill patients (n = 20) subjected to trauma, surgical complications, and/or bacteremia who were treated in the ICU and showed no risk of bleeding complications were included. Reference groups of metabolically healthy volunteers and patients served as the control/reference groups. Percutaneous muscle biopsy was obtained from both patients and healthy volunteers. Total free amino acids in skeletal muscle decreased 59% (p < .001) and skeletal muscle glutamine concentration decreased 72% (p < .001) in the critically ill patients. Basic amino acids decreased 49% (p < .001). Branch-chain amino acids increased 39% (p < .01), and aromatic amino acids increased 88% (p < .001) in the patients. Adenosine triphosphate (ATP) was reduced by 12% (p < .01). Total creatine concentration increased by 26% (p < .001) due to an 80% increase in free creatine (p < .001). The phosphorylated creatine fraction of total creatine decreased 22% (p < .001) in the patients. Alkali-soluble protein/DNA decreased 24% (p < .01) and fat free solid/DNA decreased 21% (P <.01) in patients sampled on or after ICU day 5 compared with the reference group. Muscle water increased 10% due to a doubling of the extracellular water fraction. Although critically ill patients are a very heterogeneous group from a clinical point of view, there is a remarkable homogeneity in many of the biochemical parameters regardless of the severity of illness and the length of the ICU admission. The three most consistent differences were the skeletal muscle low glutamine concentration, the decrease in protein content, and the increase in extracellular water in the patients.

  4. [An experimental study on a slow-release complex with rifampicin-polylactic-co-glycolic acid-calcium 
phosphate cement].

    Science.gov (United States)

    Wu, Jianhuang; Ding, Zhou; Lei, Qing; Li, Miao; Liang, Yan; Lu, Tao

    2016-09-28

    To prepare the slow-release complex with rifampicin (RFP)-polylactic-co-glycolic acid (PLGA)-calcium phosphate cement (CPC) (RFP-PLGA-CPC complex), and to study its physical and chemical properties and drug release properties in vitro.
 The emulsification-solvent evaporation method was adopted to prepare rifampicin polylactic acid-glycolic acid (RFP-PLGA) slow-release microspheres, which were divided into 3 groups: a calcium phosphate bone cement group (CPC group), a CPC embedded with RFP group (RFP-CPC group), and a PLGA slow-release microspheres carrying RFP and the self-curing CPC group (RFP- PLGA-CPC complex group). The solidification time and porosity of materials were determined. The drug release experiments in vitro were carried out to observe the compressive strength, the change of section morphology before and after drug release. 
 The CPC group showed the shortest solidification time, while the RFP-PLGA-CPC complex group had the longest one. There was statistical difference in the porosity between the CPC group and the RFP-CPC group (P<0.05); Compared to the RFP-PLGA-CPC complex group, the porosity in the CPC group and the RFP-CPC group were significantly changed (both P<0.01). There was significant difference in the compressive strength between the RFP- PLGA-CPC complex group and the CPC group (P<0.01), while there was significant difference in the compressive strength between the RFP-CPC group and the CPC group (3 days: P<0.05; 30 and 60 days: P<0.01). The change of the compressive strength in the CPC was not significant in the whole process of degradation. The sizes of PLGA microspheres were uniform, with the particle size between 100-150 μm. The microspheres were spheres or spheroids, and their surface was smooth without the attached impurities. There was no significant change in the section gap in the CPC group after soaking for 3 to 60 days. The microstructure change in the RFP-CPC group was small, and the cross section was formed by small

  5. Dolomite phosphate rock (DPR) application in acidic sandy soil in reducing leaching of phosphorus and heavy metals-a column leaching study.

    Science.gov (United States)

    Yang, Yuangen; He, Zhenli; Yang, Xiaoe; Stoffella, Peter J

    2013-06-01

    A column leaching study was designed to investigate the leaching potential of phosphorus (P) and heavy metals from acidic sandy soils applied with dolomite phosphate rock (DPR) fertilizers containing varying amounts of DPR material and N-Viro soils. DPR fertilizers were made from DPR materials mixing with N-Viro soils at the ratios of 30, 40, 50, 60, and 70 %, and applied in acidic sandy soils at the level of 100 mg available P per kilogram soil. A control and a soluble P chemical fertilizer were also included. The amended soils were incubated at room temperature with 70 % field water holding capacity for 21 days before packed into a soil column and subjected to leaching. Seven leaching events were conducted at days 1, 3, 7, 14, 28, 56, and 70, respectively, and 258.9 mL of deionized water was applied at each leaching events. The leachate was collected for the analyses of pH, electrical conductivity (EC), dissolved organic carbon (DOC), major elements, and heavy metals. DPR fertilizer application resulted in elevations up to 1 unit in pH, 7-10 times in EC, and 20-40 times in K and Ca concentrations, but 3-10 times reduction in P concentration in the leachate as compared with the chemical fertilizer or the control. After seven leaching events, DPR fertilizers with adequate DPR materials significantly reduced cumulative leaching losses of Fe, P, Mn, Cu, and Zn by 20, 55, 3.7, 2.7, and 2.5 times than chemical fertilizer or control. Even though higher cumulative losses of Pb, Co, and Ni were observed after DPR fertilizer application, the loss of Pb, Co, and Ni in leachate was <0.10 mg (in total 1,812 mL leachate). Significant correlations of pH (negative) and DOC (positive) with Cu, Pb, and Zn (P<0.01) in leachate were observed. The results indicated that DPR fertilizers had a great advantage over the soluble chemical fertilizer in reducing P loss from the acidic sandy soil with minimal likelihood of heavy metal risk to the water environment. pH elevation and high

  6. Evolution of a Double Amino Acid Substitution in the 5-Enolpyruvylshikimate-3-Phosphate Synthase in Eleusine indica Conferring High-Level Glyphosate Resistance1

    Science.gov (United States)

    Yu, Qin; Jalaludin, Adam; Han, Heping; Chen, Ming; Sammons, R. Douglas; Powles, Stephen B.

    2015-01-01

    Glyphosate is the most important and widely used herbicide in world agriculture. Intensive glyphosate selection has resulted in the widespread evolution of glyphosate-resistant weed populations, threatening the sustainability of this valuable once-in-a-century agrochemical. Field-evolved glyphosate resistance due to known resistance mechanisms is generally low to modest. Here, working with a highly glyphosate-resistant Eleusine indica population, we identified a double amino acid substitution (T102I + P106S [TIPS]) in the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene in glyphosate-resistant individuals. This TIPS mutation recreates the biotechnology-engineered commercial first generation glyphosate-tolerant EPSPS in corn (Zea mays) and now in other crops. In E. indica, the naturally evolved TIPS mutants are highly (more than 180-fold) resistant to glyphosate compared with the wild type and more resistant (more than 32-fold) than the previously known P106S mutants. The E. indica TIPS EPSPS showed very high-level (2,647-fold) in vitro resistance to glyphosate relative to the wild type and is more resistant (600-fold) than the P106S variant. The evolution of the TIPS mutation in crop fields under glyphosate selection is likely a sequential event, with the P106S mutation being selected first and fixed, followed by the T102I mutation to create the highly resistant TIPS EPSPS. The sequential evolution of the TIPS mutation endowing high-level glyphosate resistance is an important mechanism by which plants adapt to intense herbicide selection and a dramatic example of evolution in action. PMID:25717039

  7. On the synthesis and characterization of β-tricalcium phosphate scaffolds coated with collagen or poly (D, L-lactic acid) for alveolar bone augmentation.

    Science.gov (United States)

    Deschamps, Isadora S; Magrin, Gabriel L; Magini, Ricardo S; Fredel, Márcio C; Benfatti, Cesar A M; M Souza, Júlio C

    2017-01-01

    After tooth loss, dimensional alterations on the alveolar bone ridge can occur that can negatively affect the placement of dental implants. The purpose of this study was to evaluate the synthesis, and mechanical properties of β-tricalcium phosphate (β-TCP) scaffolds coated with bioabsorbable polymers, namely, collagen and poly (D, L-lactic acid) (PDLLA). β-TCP powder was obtained by reactive milling and then characterized by X-ray diffraction and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). β-TCP scaffolds were obtained by replica method, in which polyurethane foams are immersed in β-TCP suspension and thereafter submitted to a thermal treatment to remove the polyurethane and sinter the ceramic. Type-I collagen or PDLLA were used to coat the β-TCP scaffolds by dip-coating method. Scaffolds were separated in four groups depending on the coating material: noncoated (Group A), double immersion in collagen (Group B), double immersion in PDLLA (Group C), and ten immersions in PDLLA (Group D). Samples were characterized by compressive tests and SEM/EDS. Data were statistically analyzed through two-way ANOVA (p = 0.05). Chemical and microscopic analyses revealed proper morphology and chemical composition of powder particles and scaffolds with or without polymeric coatings. Scaffolds coated with PDLLA showed higher compressive strength (0.11 ± 0.054 MPa) than those of collagen (0.022 ± 0.012 MPa) or noncoated groups (0.024 ± 0.012 MPa). The coating method of β-TCP with PDLLA revealed a potential strategy to increase the mechanical strength of porous ceramic materials while collagen can enhance cell migration.

  8. Post-mortem changes in the concentration of lactic acid, phosphates and pH in the muscles of wild rabbits (Oryctolagus cuniculus) according to the perimortal situation.

    Science.gov (United States)

    Mačanga, Ján; Koréneková, Beáta; Nagy, Jozef; Marcinčák, Slavomir; Popelka, Peter; Kožárová, Ivona; Korének, Marián

    2011-08-01

    In this study changes in the concentrations of lactate, phosphates, and pH values of water extracts of muscles of transported and hunted rabbits during ripening were determined. Concentrations of lactate were higher in the muscles of hunted rabbits. The highest differences were obtained 24h after kill/hunt. Concentrations of lactate in the muscles of hunted rabbits were decreasing, while in the muscles of transported rabbits we observed it to increase in the 7th day and then decrease in the 14th day. Higher concentrations of phosphates were found in the muscles of transported wild rabbits. During the ripening process concentrations of phosphates were decreasing in muscles of both groups. Muscles of hunted rabbits had lower pH values during the whole ripening process. Our research showed that concentrations of lactate, phosphates and pH value post-mortem depended on the perimortal situations. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. [The 32P-incorporation into nucleic acids and adenosine phosphates of the rat brain after acute and chronic influence of meclofenoxate (author's transl)].

    Science.gov (United States)

    Kanig, K; Tencheva, Z S; Nitschki, J; Dingler, W H

    1976-01-01

    Beta-Dimethylaminoethyl-p-chlorophenoxyacetate hydrochloride (meclofenoxate, Helfergin) was adminstered orally in dosages of 300 mg/kg 3 times during an 18-h period. The incorporation rate of the total and cytoplasmic RNA as well as of ATP, ADP and AMP decreased. Contradictory results were obtained after a 16-day treatment with orally 300 mg/kg per day: while the 32P-incorporation rate of the cytoplasmic RNA and the 3 adenosine phosphates increased, the nuclear RNA showed a correspondent diminishing. No changes of the ATP content could be observed in any group. The differences between the acute and chronic experiments could be explained by a different excitation of the animals and by the very different dosages. The increased 32P-incorporation into the cytoplasmic and into the adenosine phosphates in the chronic experiments are explained by a stimulation of the pentose phosphate shunt which yields mainly the phosphate group for the synthesis of AMP.

  10. Toxicological review of inorganic phosphates.

    Science.gov (United States)

    Weiner, M L; Salminen, W F; Larson, P R; Barter, R A; Kranetz, J L; Simon, G S

    2001-08-01

    below 70 mg/kg/day (JECFA, 1964, 1982a) [JECFA (Joint FAO/WHO Expert Committee on Food Additives 1964. Specifications for the Identity and Purity of Food Additives and their Toxicological Evaluation) Emulsifiers, Stabilizers, Bleaching, and Maturing Agents. Technical Report Series of the World Health Organization 281; ECFA (Joint FAO/WHO Expert Committee on Food Additives 1982a. Phosphoric Acid and Phosphate Salts. ICS/FA/82)].

  11. Light weight phosphate cements

    Science.gov (United States)

    Wagh, Arun S.; Natarajan, Ramkumar,; Kahn, David

    2010-03-09

    A sealant having a specific gravity in the range of from about 0.7 to about 1.6 for heavy oil and/or coal bed methane fields is disclosed. The sealant has a binder including an oxide or hydroxide of Al or of Fe and a phosphoric acid solution. The binder may have MgO or an oxide of Fe and/or an acid phosphate. The binder is present from about 20 to about 50% by weight of the sealant with a lightweight additive present in the range of from about 1 to about 10% by weight of said sealant, a filler, and water sufficient to provide chemically bound water present in the range of from about 9 to about 36% by weight of the sealant when set. A porous ceramic is also disclosed.

  12. Safety test of a supplement, 5-aminolevulinic acid phosphate with sodium ferrous citrate, in diabetic patients treated with oral hypoglycemic agents

    Directory of Open Access Journals (Sweden)

    Naohide Yamashita

    2014-09-01

    Full Text Available Objective: This study aimed to examine the safety of 5-aminolevulinic acid phosphate (5-ALA with sodium ferrous citrate (SFC in diabetic patients treated with one or more oral hypoglycemic agents (OHAs. Background: Recent intervention studies performed in the USA and Japan have shown that a nutritional supplement of 5-ALA with SFC efficiently reduced blood glucose levels in pre-diabetic population without any adverse events. Thus, it was anticipated that 5-ALA with SFC may potentially be taken as a beneficial supplement by diabetic patients who were being treated with OHA therapy. Nevertheless, it is important to examine its safety and efficacy in diabetic population. Methods: This study was a prospective single-blinded, randomized, placebo-controlled and parallel-group comparison study. Medically treated diabetic patients between the ages of 30 and 75 were recruited from the Tokyo metropolitan area of Japan and 45 subjects were selected after screening. These subjects were randomly assigned to three groups: daily intake of 15mg 5-ALA, 50mg 5-ALA, and a placebo (n=15, respectively. The supplement or placebo was administered for 12 weeks followed by a four week washout period. The primary endpoint was safety and occurrence of hypoglycemic attack, while the secondary endpoint was changes of fasting blood glucose (FBG and hemoglobin A1c (HbA1c. Results: Adverse events related to 5-ALA with SFC were not observed in all the groups. Abnormalities in blood and urine tests were not observed either. Significant decrease in FBG was not detected in all the groups. However, there was a small but significant decrease in HbA1c at 4 and 8 week in the 15 mg 5-ALA group. Significant decrease in HbA1c was not observed in the 50 mg 5-ALA group, although a tendency to decrease after 4 weeks was apparent. Conclusion: 5-ALA with SFC is a safe and potentially beneficial supplement if taken by diabetic patients treated with OHAs.

  13. [Mechanical properties of polylactic acid/beta-tricalcium phosphate composite scaffold with double channels based on three-dimensional printing technique].

    Science.gov (United States)

    Lian, Qin; Zhuang, Pei; Li, Changhai; Jin, Zhongmin; Li, Dichen

    2014-03-01

    To improve the poor mechanical strength of porous ceramic scaffold, an integrated method based on three-dimensional (3-D) printing technique is developed to incorporate the controlled double-channel porous structure into the polylactic acid/beta-tricalcium phosphate (PLA/beta-TCP) reinforced composite scaffolds (double-channel composite scaffold) to improve their tissue regeneration capability and the mechanical properties. The designed double-channel structure inside the ceramic scaffold consisted of both primary and secondary micropipes, which parallel but un-connected. The set of primary channels was used for cell ingrowth, while the set of secondary channels was used for the PLA perfusion. Integration technology of 3-D printing technique and gel-casting was firstly used to fabricate the double-channel ceramic scaffolds. PLA/beta-TCP composite scaffolds were obtained by the polymer gravity perfusion process to pour PLA solution into the double-channel ceramic scaffolds through the secondary channel set. Microscope, porosity, and mechanical experiments for the standard samples were used to evaluate the composite properties. The ceramic scaffold with only the primary channel (single-channel scaffold) was also prepared as a control. Morphology observation results showed that there was no PLA inside the primary channels of the double-channel composite scaffolds but a dense interface layer between PLA and beta-TCP obviously formed on the inner wall of the secondary channels by the PLA penetration during the perfusion process. Finite element simulation found that the compressive strength of the double-channel composite scaffold was less than that of the single-channel scaffold; however, mechanical tests found that the maximum compressive strength of the double-channel composite scaffold [(21.25 +/- 1.15) MPa] was higher than that of the single-channel scaffold[ (9.76 +/- 0.64) MPa]. The double-channel composite scaffolds fabricated by 3-D printing technique have

  14. Improved Manganese Phosphate Coatings

    Science.gov (United States)

    1975-04-01

    AD K/ . / R-TR-75-034 IMPROVED MANGANESE PHOSPHATE COATINGS HENRY CRAIN - APRIL 1975 RESEARCH DIRECTORATE DISTRIBUTION STATEMENT Approved for public...which superior manganese phosphate coatings are producel. The phosphate coatings were applied at temp- eratures above 2124F and with -.anganese...temperature for the conversion of mlnganese dihydrogen phosphate [(P(HjPO•’)] to manganese phosphate [Nns(PO4)J]. 1 A ii UNCLASSIFIED SE[CURITY CL. A

  15. Acquired acid resistance of human enamel treated with laser (Er:YAG laser and Co 2 laser and acidulated phosphate fluoride treatment: An in vitro atomic emission spectrometry analysis

    Directory of Open Access Journals (Sweden)

    Anju Mathew

    2013-01-01

    Full Text Available Background: Dental caries is essentially a process of diffusion and dissolution. If the aspect of dissolution can be curtailed some degree of prevention can be achieved. Aims: The present study was carried out to evaluate and compare the effect of Er:YAG laser and Co 2 laser irradiation combined with acidulated phosphate fluoride treatment on in vitro acid resistance of human enamel. Design: An in vitro study was carried out on 30 human premolars to evaluate the enamel′s acid resistance using an atomic emission spectrometry analysis. Materials and Methods: A total of 60 enamel specimens were prepared from 30 human premolars and were randomly assigned to 6 groups: (1 Untreated (control; (2 1.23% acidulated phosphate fluoride (APF gel application alone for 4 min; (3 Er:YAG laser treatment alone; (4 Co 2 laser treatment alone; (5 Er:YAG laser + APF gel application; (6 Co 2 laser + APF gel application. The specimens were then individually immersed in 5 ml of acetate buffer solution (0.1 mol/L, pH 4.5 and incubated at 37°C for 24 h, and the acid resistance was evaluated by determining the calcium ion concentration using the atomic emission spectrometry. Statistical Analysis: An ANOVA model was constructed (P value of 0.05, followed by Tukey′s test for multiple pair wise comparisons of mean values. Results: Significant differences were found between the control group and the test groups ( P < 0.001. Conclusions: Combining acidulated phosphate fluoride with either Er:YAG or Co 2 laser had a synergistic effect in decreasing the enamel demineralization more than either fluoride treatment or laser treatment alone.

  16. Tuning the Degradation Rate of Calcium Phosphate Cements by Incorporating Mixtures of Polylactic-co-Glycolic Acid Microspheres and Glucono-Delta-Lactone Microparticles

    NARCIS (Netherlands)

    Sariibrahimoglu, K.; An, J.; Oirschot, B.A.J.A. van; Nijhuis, A.W.G.; Eman, R.M.; Alblas, J.; Wolke, J.G.C.; Beucken, J.J.J.P van den; Leeuwenburgh, S.C.G.; Jansen, J.A.

    2014-01-01

    Calcium phosphate cements (CPCs) are frequently used as synthetic bone graft materials in view of their excellent osteocompatibility and clinical handling behavior. Hydroxyapatite-forming CPCs, however, degrade at very low rates, thereby limiting complete bone regeneration. The current study has

  17. 13C based proteinogenic amino acid (PAA and metabolic flux ratio analysis of Lactococcus lactis reveals changes in pentose phosphate (PP pathway in response to agitation and temperature related stresses

    Directory of Open Access Journals (Sweden)

    Kamalrul Azlan Azizan

    2017-07-01

    Full Text Available Lactococcus lactis subsp. cremoris MG1363 is an important starter culture for dairy fermentation. During industrial fermentations, L. lactis is constantly exposed to stresses that affect the growth and performance of the bacterium. Although the response of L. lactis to several stresses has been described, the adaptation mechanisms at the level of in vivo fluxes have seldom been described. To gain insights into cellular metabolism, 13C metabolic flux analysis and gas chromatography mass spectrometry (GC-MS were used to measure the flux ratios of active pathways in the central metabolism of L. lactis when subjected to three conditions varying in temperature (30°C, 37°C and agitation (with and without agitation at 150 rpm. Collectively, the concentrations of proteinogenic amino acids (PAAs and free fatty acids (FAAs were compared, and Pearson correlation analysis (r was calculated to measure the pairwise relationship between PAAs. Branched chain and aromatic amino acids, threonine, serine, lysine and histidine were correlated strongly, suggesting changes in flux regulation in glycolysis, the pentose phosphate (PP pathway, malic enzyme and anaplerotic reaction catalysed by pyruvate carboxylase (pycA. Flux ratio analysis revealed that glucose was mainly converted by glycolysis, highlighting the stability of L. lactis’ central carbon metabolism despite different conditions. Higher flux ratios through oxaloacetate (OAA from pyruvate (PYR reaction in all conditions suggested the activation of pyruvate carboxylate (pycA in L. lactis, in response to acid stress during exponential phase. Subsequently, more significant flux ratio differences were seen through the oxidative and non-oxidative pentose phosphate (PP pathways, malic enzyme, and serine and C1 metabolism, suggesting NADPH requirements in response to environmental stimuli. These reactions could play an important role in optimization strategies for metabolic engineering in L. lactis. Overall

  18. Phosphate Fertilizer Industry: New Source Performance Standards - 40 CFR 60 Subparts T, U, V, W & X

    Science.gov (United States)

    Learn about the the NSPS regulations for Diammonium phosphate plants, superphosphoric acid plants, granular triple superphosphate storage facilities, triple superphosphate plants & wet-process phosphoric acid plants

  19. 40 CFR 422.40 - Applicability; description of the defluorinated phosphate rock subcategory.

    Science.gov (United States)

    2010-07-01

    ... defluorinated phosphate rock subcategory. 422.40 Section 422.40 Protection of Environment ENVIRONMENTAL... Defluorinated Phosphate Rock Subcategory § 422.40 Applicability; description of the defluorinated phosphate rock... phosphate rock by application of high temperature treatment along with wet process phosphoric acid, silica...

  20. SAR studies of 3-arylpropionic acids as potent and selective agonists of sphingosine-1-phosphate receptor-1 (S1P1) with enhanced pharmacokinetic properties.

    Science.gov (United States)

    Yan, Lin; Huo, Pei; Hale, Jeffrey J; Mills, Sander G; Hajdu, Richard; Keohane, Carol A; Rosenbach, Mark J; Milligan, James A; Shei, Gan-Ju; Chrebet, Gary; Bergstrom, James; Card, Deborah; Mandala, Suzanne M

    2007-02-01

    Structure-activity relationship (SAR) studies of 3-arylpropionic acids-a class of novel S1P(1) selective agonists-by introducing substitution to the propionic acid chain and replacing the adjacent phenyl ring with pyridine led to a series of modified 3-arylpropionic acids with enhanced half-life in rat. These analogs (e.g., cyclopropanecarboxylic acids) exhibited longer half-life in rat than did unmodified 3-arylpropionic acids. This result suggests that metabolic oxidation at the propionic acid chain, particularly at the C3 benzylic position of 3-arylpropionic acids, is probably responsible for their short half-life in rodent.

  1. Phosphate acquisition efficiency and phosphate starvation tolerance ...

    Indian Academy of Sciences (India)

    have reported the presence as well as the expression of a previously characterized rice gene, phosphate starvation tolerance locus (PSTOL1) in a set of .... surrounding the field to prevent any invasion of phosphate through other irrigation ... After germination, eight genotypes were allowed to grow in a glass plate dipped ...

  2. Microflow Visualization of Tri-n-butyl-Phosphate/Dodecane and Nitric Acid in a Centrifugal Contactor. Part I: Flow Regimes, Transitions and Hysteresis

    Energy Technology Data Exchange (ETDEWEB)

    de Almeida, Valmor [Univ. of Massachusetts, Lowell, MA (United States); Birdwell Jr, Joseph F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DePaoli, David W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Tsouris, Costas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-10-01

    Despite the common use of centrifugal contactors in nuclear solvent extraction ap- plications, much is unknown about the underlying micro ow structure. This lack of knowledge hampers the development of a modern continuum theory able to predict mixing and transport phenomena for solvent extraction processes. The ability to observe the micromixing ow and distinguish the motion and con guration of the phases involved is of great importance theoretically and practically. To that end, we report on direct, high-speed visualization of the micro ow structure for the tri-n- butyl-phosphate (TBP)/dodecane/nitric acid system. Further insight is obtained by simultaneous measurement of the electrical resistance of the phase mixture to support visual observations. This work sheds light on a fluid micro ow region at the foot of the mixing zone of the contactor resolving the microsecond/micrometer motion of the continuous and dispersed phases. The system in this study is the most prevalent solvent extraction combination used in the nuclear reprocessing industry to extract metal ions from spent nuclear fuel from a nitric acid aqueous solution into an organic mixture of TBP and dodecane. The purpose of this work is to describe salient features of the behavior of this system, heretofore unknown, to guide the development of a predictive modeling and simulation approach. The time and space resolution of the high-speed video imaging equipment used allowed for the identification of the dispersed phases for various combinations of ow rates of the organic and aqueous streams at realistic operating conditions. Two ow regimes were found, namely, an aqueous-continuous (organic-dispersed) regime, and an organic-continuous (aqueous-dispersed) regime with an associated hysteresis loop. In addition, in both ow regimes there was always a dispersed gas phase resulting from significant air entrainment. This study identified local details of the dispersed phase state at all ow conditions. For

  3. Stimulation of d- and l-lactate dehydrogenases transcriptional levels in presence of diammonium hydrogen phosphate resulting to enhanced lactic acid production by Lactobacillus strain.

    Science.gov (United States)

    Singhvi, Mamata; Zendo, Takeshi; Iida, Hiroshi; Gokhale, Digambar; Sonomoto, Kenji

    2017-12-01

    The present study revealed the effect of nitrogen sources on lactic acid production and stimulation of d- and l-lactate dehydrogenases (LDH) of parent Lactobacillus lactis NCIM 2368 and its mutant RM2-24 generated after UV mutagenesis. Both the parent and mutant strains were evaluated for d-lactic acid production in control and modified media. The modified media did not show remarkable effect on lactic acid production in case of parent whereas mutant exhibited significant enhancement in d-lactic acid production along with the appearance of l-lactic acid in the broth. Both LDH activities and specific activities were found to be higher in mutant than the parent strain. These results suggested that the diammonium hydrogen phosphate in modified media triggered the expression of LDH genes leading to enhanced lactic acid production. This observation has been proved by studying the expression levels of d- and l-LDH genes of parent and mutant in control and modified media using quantitative RT-PCR technique. In case of mutant, the transcriptional levels of d-LDH and l-LDH increased ∼17 fold and ∼1.38 fold respectively in modified medium compared to the values obtained with control medium. In case of parent, no significant change in transcriptional levels of d- and l-LDH was found when the cells were grown in either control medium or modified medium. This study suggested that the mutant, RM2-24 has l-LDH gene which is expressed in presence of (NH 4 ) 2 HPO 4 resulting in l-lactic acid production. Co-production of l-lactic acid in d-lactic acid fermentation may be detrimental in the PLA production. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  4. Glucose-6-phosphate dehydrogenase

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003671.htm Glucose-6-phosphate dehydrogenase test To use the sharing features on this page, please enable JavaScript. Glucose-6-phosphate dehydrogenase (G6PD) is a protein that ...

  5. Maize endophytic bacteria as mineral phosphate solubilizers.

    Science.gov (United States)

    de Abreu, C S; Figueiredo, J E F; Oliveira, C A; Dos Santos, V L; Gomes, E A; Ribeiro, V P; Barros, B A; Lana, U G P; Marriel, I E

    2017-02-16

    In the present study, we demonstrated the in vitro activity of endophytic phosphate-solubilizing bacteria (PSB). Fifty-five endophytic PSB that were isolated from sap, leaves, and roots of maize were tested for their ability to solubilize tricalcium phosphate and produce organic acid. Partial sequencing of the 16S rRNA-encoding gene showed that the isolates were from the genus Bacillus and different species of Enterobacteriaceae. The phosphate solubilization index on solid medium and phosphate solubilization in liquid medium varied significantly among the isolates. There was a statistically significant difference (P ≤ 0.05) for both, the values of phosphate-solubilizing activity and pH of the growth medium, among the isolates. Pearson correlation was statistically significant (P ≤ 0.05) between P-solubilization and pH (R = -0.38), and between the gluconic acid production and the lowering of the pH of the liquid medium at 6 (R = 0.28) and 9 days (R = 0.39). Gluconic acid production was prevalent in all the PSB studied, and Bacillus species were most efficient in solubilizing phosphate. This is the first report on the characterization of bacterial endophytes from maize and their use as potential biofertilizers. In addition, this may provide an alternative strategy for improving the phosphorus acquisition efficiency of crop plants in tropical soils.

  6. Research and engineering assessment of biological solubilization of phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, R.D.; McIlwain, M.E.; Losinski, S.J.; Taylor, D.D.

    1993-03-01

    This research and engineering assessment examined a microbial phosphate solubilization process as a method of recovering phosphate from phosphorus containing ore compared to the existing wet acid and electric arc methods. A total of 860 microbial isolates, collected from a range of natural environments were tested for their ability to solubilize phosphate from rock phosphate. A bacterium (Pseudomonas cepacia) was selected for extensive characterization and evaluation of the mechanism of phosphate solubilization and of process engineering parameters necessary to recover phosphate from rock phosphate. These studies found that concentration of hydrogen ion and production of organic acids arising from oxidation of the carbon source facilitated microbial solubilization of both pure chemical insoluble phosphate compounds and phosphate rock. Genetic studies found that phosphate solubilization was linked to an enzyme system (glucose dehydrogenase). Process-related studies found that a critical solids density of 1% by weight (ore to liquid) was necessary for optimal solubilization. An engineering analysis evaluated the cost and energy requirements for a 2 million ton per year sized plant, whose size was selected to be comparable to existing wet acid plants.

  7. Phosphate Solubilization and Gene Expression of Phosphate-Solubilizing Bacterium Burkholderia multivorans WS-FJ9 under Different Levels of Soluble Phosphate.

    Science.gov (United States)

    Zeng, Qingwei; Wu, Xiaoqin; Wang, Jiangchuan; Ding, Xiaolei

    2017-04-28

    Phosphate-solubilizing bacteria (PSB) have the ability to dissolve insoluble phosphate and enhance soil fertility. However, the growth and mineral phosphate solubilization of PSB could be affected by exogenous soluble phosphate and the mechanism has not been fully understood. In the present study, the growth and mineral phosphate-solubilizing characteristics of PSB strain Burkholderia multivorans WS-FJ9 were investigated at six levels of exogenous soluble phosphate (0, 0.5, 1, 5, 10, and 20 mM). The WS-FJ9 strain showed better growth at high levels of soluble phosphate. The phosphate-solubilizing activity of WS-FJ9 was reduced as the soluble phosphate concentration increased, as well as the production of pyruvic acid. Transcriptome profiling of WS-FJ9 at three levels of exogenous soluble phosphate (0, 5, and 20 mM) identified 446 differentially expressed genes, among which 44 genes were continuously up-regulated when soluble phosphate concentration was increased and 81 genes were continuously down-regulated. Some genes related to cell growth were continuously up-regulated, which would account for the better growth of WS-FJ9 at high levels of soluble phosphate. Genes involved in glucose metabolism, including glycerate kinase, 2-oxoglutarate dehydrogenase, and sugar ABC-type transporter, were continuously down-regulated, which indicates that metabolic channeling of glucose towards the phosphorylative pathway was negatively regulated by soluble phosphate. These findings represent an important first step in understanding the molecular mechanisms of soluble phosphate effects on the growth and mineral phosphate solubilization of PSB.

  8. Clindamycin lotion alone versus combination lotion of clindamycin phosphate plus tretinoin versus combination lotion of clindamycin phosphate plus salicylic acid in the topical treatment of mild to moderate acne vulgaris: A randomized control trial

    Directory of Open Access Journals (Sweden)

    NilFroushzadeh Mohammad

    2009-01-01

    Full Text Available Background: Acne vulgaris is a common skin disease that affects 85% to 100% of people at some time during their lives. It is characterized by noninflammatory follicular papules or comedones and by inflammatory papules, pustules, and nodules in its more severe forms. Aims: To compare the efficacy of combination treatment of clindamycin+salicylic acid, versus clindamycin+tretinoin versus clindamycin alone in the treatment of the mild-to-moderate acne vulgaris. Methods: This was a single-blinded, randomized clinical trial.Forty-two female patients (age range: 15-25 years with mild-to-moderate acne vulgaris were selected randomly and subsequently randomized to 3 groups. Group A patients were treated with 1% clindamycin lotion (C lotion twice daily. Group B patients were treated with 1% clindamycin+0.025% tretinoin lotion once nightly (CT lotion. Group C patients were treated with 1% clindamycin+2% salicylic acid lotion twice daily (CS lotion for 12 weeks. For comparison of efficacy of these treatments, and regarding the skewed distribution of the data, Kruskal-Wallis Test and Mann-Whitney U test were used. SPSS software was used for statistical analysis. Results: There was a significant difference between 3 types of treatment in the respect of the total lesion count (TLC improvement ( P = 0.039. The efficacy of treatment on Acne Severity Index (ASI was maximum for CS lotion (81.80% reduction in ASI. CT lotion reduced ASI by as much as 73.73% during 12 weeks of treatment. The efficacy of C lotion was calculated to be 37.87% in the reduction of ASI. Conclusions: Our data suggested that the efficacy of CS lotion was significantly more than C lotion with respect to the TLC and ASI, although there was no significant difference between CS and CT lotion.

  9. Clindamycin lotion alone versus combination lotion of clindamycin phosphate plus tretinoin versus combination lotion of clindamycin phosphate plus salicylic acid in the topical treatment of mild to moderate acne vulgaris: a randomized control trial.

    Science.gov (United States)

    NilFroushzadeh, Mohammad Ali; Siadat, Amir Hossein; Baradaran, Elahe Haft; Moradi, Shahram

    2009-01-01

    Acne vulgaris is a common skin disease that affects 85% to 100% of people at some time during their lives. It is characterized by noninflammatory follicular papules or comedones and by inflammatory papules, pustules, and nodules in its more severe forms. To compare the efficacy of combination treatment of clindamycin+salicylic acid, versus clindamycin+tretinoin versus clindamycin alone in the treatment of the mild-to-moderate acne vulgaris. This was a single-blinded, randomized clinical trial.Forty-two female patients (age range: 15-25 years) with mild-to-moderate acne vulgaris were selected randomly and subsequently randomized to 3 groups. Group A patients were treated with 1% clindamycin lotion (C lotion) twice daily. Group B patients were treated with 1% clindamycin+0.025% tretinoin lotion once nightly (CT lotion). Group C patients were treated with 1% clindamycin+2% salicylic acid lotion twice daily (CS lotion) for 12 weeks. For comparison of efficacy of these treatments, and regarding the skewed distribution of the data, Kruskal-Wallis Test and Mann-Whitney U test were used. SPSS software was used for statistical analysis. There was a significant difference between 3 types of treatment in the respect of the total lesion count (TLC) improvement (P = 0.039). The efficacy of treatment on Acne Severity Index (ASI) was maximum for CS lotion (81.80% reduction in ASI). CT lotion reduced ASI by as much as 73.73% during 12 weeks of treatment. The efficacy of C lotion was calculated to be 37.87% in the reduction of ASI. Our data suggested that the efficacy of CS lotion was significantly more than C lotion with respect to the TLC and ASI, although there was no significant difference between CS and CT lotion.

  10. Structures of gamma-aminobutyric acid (GABA) aminotransferase, a pyridoxal 5'-phosphate, and [2Fe-2S] cluster-containing enzyme, complexed with gamma-ethynyl-GABA and with the antiepilepsy drug vigabatrin.

    Science.gov (United States)

    Storici, Paola; De Biase, Daniela; Bossa, Francesco; Bruno, Stefano; Mozzarelli, Andrea; Peneff, Caroline; Silverman, Richard B; Schirmer, Tilman

    2004-01-02

    Gamma-aminobutyric acid aminotransferase (GABA-AT) is a pyridoxal 5'-phosphate-dependent enzyme responsible for the degradation of the inhibitory neurotransmitter GABA. GABA-AT is a validated target for antiepilepsy drugs because its selective inhibition raises GABA concentrations in brain. The antiepilepsy drug, gamma-vinyl-GABA (vigabatrin) has been investigated in the past by various biochemical methods and resulted in several proposals for its mechanisms of inactivation. In this study we solved and compared the crystal structures of pig liver GABA-AT in its native form (to 2.3-A resolution) and in complex with vigabatrin as well as with the close analogue gamma-ethynyl-GABA (to 2.3 and 2.8 A, respectively). Both inactivators form a covalent ternary adduct with the active site Lys-329 and the pyridoxal 5'-phosphate (PLP) cofactor. The crystal structures provide direct support for specific inactivation mechanisms proposed earlier on the basis of radio-labeling experiments. The reactivity of GABA-AT crystals with the two GABA analogues was also investigated by polarized absorption microspectrophotometry. The spectral data are discussed in relation to the proposed mechanism. Intriguingly, all three structures revealed a [2Fe-2S] cluster of yet unknown function at the center of the dimeric molecule in the vicinity of the PLP cofactors.

  11. Zirconium Phosphate Supported MOF Nanoplatelets.

    Science.gov (United States)

    Kan, Yuwei; Clearfield, Abraham

    2016-06-06

    We report a rare example of the preparation of HKUST-1 metal-organic framework nanoplatelets through a step-by-step seeding procedure. Sodium ion exchanged zirconium phosphate, NaZrP, nanoplatelets were judiciously selected as support for layer-by-layer (LBL) assembly of Cu(II) and benzene-1,3,5-tricarboxylic acid (H3BTC) linkers. The first layer of Cu(II) is attached to the surface of zirconium phosphate through covalent interaction. The successive LBL growth of HKUST-1 film is then realized by soaking the NaZrP nanoplatelets in ethanolic solutions of cupric acetate and H3BTC, respectively. The amount of assembled HKUST-1 can be readily controlled by varying the number of growth cycles, which was characterized by powder X-ray diffraction and gas adsorption analyses. The successful construction of HKUST-1 on NaZrP was also supported by its catalytic performance for the oxidation of cyclohexene.

  12. Solid-State Fermentation Reduces Phytic Acid Level, Improves the Profile of Myo-Inositol Phosphates and Enhances the Availability of Selected Minerals in Flaxseed Oil Cake.

    Science.gov (United States)

    Duliński, Robert; Stodolak, Bożena; Byczyński, Łukasz; Poreda, Aleksander; Starzyńska-Janiszewska, Anna; Żyła, Krzysztof

    2017-09-01

    Flaxseed oil cake was subjected to fermentation with Rhizopus oligosporus (DSM 1964 and ATCC 64063), and the phytate (InsP6) content, myo-inositol phosphate profile and in vitro bioavailability of essential minerals were studied. Flaxseed oil cake had a phytate mass fraction of 13.9 mg/g. A 96-hour fermentation of flaxseed oil cake by R. oligosporus DSM 1964 and R. oligosporus ATCC 64063 decreased the InsP6 content by 48 and 33%, respectively. The strains had different phytate-degrading activities: fermentation of flaxseed oil cake with R. oligosporus DSM 1964 was more advantageous, yielding InsP3-5 as a predominating myo-inositol compound, while fermentation with R. oligosporus ATCC 64603 produced predominantly InsP5-6. Solid-state fermentation of flaxseed oil cake enhanced in vitro bioavailability of calcium by 14, magnesium by 3.3 and phosphorus by 2-4%.

  13. Solid-State Fermentation Reduces Phytic Acid Level, Improves the Profile of Myo-Inositol Phosphates and Enhances the Availability of Selected Minerals in Flaxseed Oil Cake

    Science.gov (United States)

    2017-01-01

    Summary Flaxseed oil cake was subjected to fermentation with Rhizopus oligosporus (DSM 1964 and ATCC 64063), and the phytate (InsP6) content, myo-inositol phosphate profile and in vitro bioavailability of essential minerals were studied. Flaxseed oil cake had a phytate mass fraction of 13.9 mg/g. A 96-hour fermentation of flaxseed oil cake by R. oligosporus DSM 1964 and R. oligosporus ATCC 64063 decreased the InsP6 content by 48 and 33%, respectively. The strains had different phytate-degrading activities: fermentation of flaxseed oil cake with R. oligosporus DSM 1964 was more advantageous, yielding InsP3-5 as a predominating myo-inositol compound, while fermentation with R. oligosporus ATCC 64603 produced predominantly InsP5-6. Solid-state fermentation of flaxseed oil cake enhanced in vitro bioavailability of calcium by 14, magnesium by 3.3 and phosphorus by 2–4%. PMID:29089855

  14. 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.

  15. Novel Development of Phosphate Treated Porous Hydroxyapatite

    Science.gov (United States)

    Doi, Kazuya; Abe, Yasuhiko; Kobatake, Reiko; Okazaki, Yohei; Oki, Yoshifumi; Naito, Yoshihito; Prananingrum, Widyasri; Tsuga, Kazuhiro

    2017-01-01

    Phosphoric acid-etching treatment to the hydroxyapatite (HA) surface can modify the solubility calcium structure. The aim of the present study was to develop phosphate treated porous HA, and the characteristic structures and stimulation abilities of bone formation were evaluated to determine its suitability as a new type of bone graft material. Although the phosphoric acid-etching treatment did not alter the three-dimensional structure, a micrometer-scale rough surface topography was created on the porous HA surface. Compared to porous HA, the porosity of phosphate treated porous HA was slightly higher and the mechanical strength was lower. Two weeks after placement of the cylindrical porous or phosphate treated porous HA in a rabbit femur, newly formed bone was detected in both groups. At the central portion of the bone defect area, substantial bone formation was detected in the phosphate treated porous HA group, with a significantly higher bone formation ratio than detected in the porous HA group. These results indicate that phosphate treated porous HA has a superior surface topography and bone formation abilities in vivo owing to the capacity for both osteoconduction and stimulation abilities of bone formation conferred by phosphoric acid etching.

  16. Biological Removal of Phosphate Using Phosphate Solubilizing Bacterial Consortium from Synthetic Wastewater: A Laboratory Scale

    Directory of Open Access Journals (Sweden)

    Dipak Paul

    2015-01-01

    Full Text Available Biological phosphate removal is an important process having gained worldwide attention and widely used for removing phosphorus from wastewater. The present investigation was aimed to screen the efficient phosphate solubilizing bacterial isolates and used to remove phosphate from synthetic wastewater under shaking flasks conditions. Pseudomonas sp. JPSB12, Enterobacter sp. TPSB20, Flavobacterium sp. TPSB23 and mixed bacterial consortium (Pseudomonas sp. JPSB12+Enterobacter sp. TPSB20+Flavobacterium sp. TPSB23 were used for the removal of phosphate. Among the individual strains, Enterobacter sp. TPSB20 was removed maximum phosphate (61.75% from synthetic wastewater in presence of glucose as a carbon source. The consortium was effectively removed phosphate (74.15-82.50% in the synthetic wastewater when compared to individual strains. The pH changes in culture medium with time and extracellular phosphatase activity (acid and alkaline were also investigated. The efficient removal of phosphate by the consortium may be due to the synergistic activity among the individual strains and phosphatase enzyme activity. The use of bacterial consortium in the remediation of phosphate contaminated aquatic environments has been discussed.

  17. Effects of Tamm-Horsfall protein with normal and reduced sialic acid content upon the crystallization of calcium phosphate and calcium oxalate in human urine

    National Research Council Canada - National Science Library

    Hallson, P C; Choong, S K; Kasidas, G P; Samuell, C T

    1997-01-01

    To examine the effects of Tamm-Horsfall protein (THP) of normal and low sialic acid content on urinary crystallization, and establish whether there are changes conducive to the formation of kidney stones...

  18. Regional analysis of groundwater phosphate concentrations under acidic sandy soils: Edaphic factors and water table strongly mediate the soil P-groundwater P relation.

    Science.gov (United States)

    Mabilde, Lisa; De Neve, Stefaan; Sleutel, Steven

    2017-12-01

    Historic long-term P application to sandy soils in NW-Europe has resulted in abundant sorption, saturation and eventually leaching of P from soil to the groundwater. Although many studies recognize the control of site-specific factors like soil texture and phosphate saturation degree (PSD), the regional-scaled relevance of effects exerted by single factors controlling P leaching is unclear. Very large observational datasets of soil and groundwater P content are furthermore required to reveal indirect controls of soil traits through mediating soil variables. We explored co-variation of phreatic groundwater orthophosphate (o-P) concentration and soil factors in sandy soils in Flanders, Belgium. Correlation analyses were complemented with an exploratory model derived using 'path analysis'. Data of oxalate-extractable Al, Fe, P and pH KCl , phosphate sorption capacity (PSC) and PSD in three depth layers (0-30, 30-60, 60-90 cm), topsoil SOC, % clay and groundwater depth (fluctuation) were interpolated to predict soil properties on exact locations of a very extensive net of groundwater monitoring wells. The mean PSD was only poorly correlated to groundwater o-P concentration, indicating the overriding control of other factors in the transport of P to the groundwater. A significant (P soil pH and groundwater table depth than by PSD indicates the likely oversimplification of the latter index to measure the long-term potential risk of P leaching. Accounting for controls on leaching not included in PSD via an alternative index, however, seems problematic as in Flanders for example groundwater o-P turned out to be higher in finer textured soils or soils with higher pedogenic Fe content, probably because of their lower pedogenic Al content and higher soil pH. Path analysis of extensive soil and groundwater datasets seems a viable way to identify prime local determinants of soil P leaching and could be further on used for 'ground-truthing' more complex P-migration simulation

  19. Removal of phosphate from aqueous solution using modified zeolite clays

    Science.gov (United States)

    Gan, Fangqun; Qin, Pinzhu; ying, Guan; Tang, Rong; Hu, Jien

    2017-09-01

    Phosphate adsorption capabilities of different treated zeolite clays were assessed from aqueous solution. Natural zeolites were treated by thermal activation over 120–800 °C for 2 h, and by hydrochloric ac-id solution from 1%-9%, respectively. The mechanisms of phosphate adsorption of these modified products were also studied through adsorption isotherms and adsorption kinetics experiments. The acid activation in-creased the phosphate sorption capacity and the highest phosphate sorption capacity occurred at AZT9 (zeo-lite activated by 9% hydrochloric acid), while thermal activation did not have the same effect. AZT9 showed higher adsorption rate than natural zeolite (ZT). The phosphate adsorption isotherms of ZT, H400 and AZT9 are fitted well with Langmuir equation in terms of R2 values. It suggested that the adsorption of phosphate on zeolite was homogeneous multilayer adsorption. Based on R2 values, the kinetics of phosphate adsorption on these three zeolites can be satisfactorily described by pseudo-second-order kinetic equation. Results of this study suggested that acid modified zeolite could be potentially used as a promising adsorption media for phosphate removal.

  20. Aluminum and iron contents in phosphate treated swamp rice farm ...

    African Journals Online (AJOL)

    In 2006 aluminum and iron contents were determined in phosphate treated swamp rice farm of Mbiabet, Akwa Ibom State. The objectives were to determine the aluminum and iron contents, the effect of drying, phosphate and lime application in an acid sulphate soil grown to rice in Nigeria. The soil samples used were ...

  1. Supplementation of medium with diammonium hydrogen phosphate enhanced the D-lactate dehydrogenase levels leading to increased D-lactic acid productivity.

    Science.gov (United States)

    Singhvi, Mamata; Jadhav, Akanksha; Gokhale, Digambar

    2013-10-01

    The production of D-lactic acid by Lactobacillus lactis RM2-24 was investigated using modified media to increase the efficiency of the fermentation process. The results indicated that the addition of 5 g/l peptone and 1 g/l (NH4)2HPO4 enhanced D-lactic acid production by 32%, as compared to that obtained from non supplemented media, with a productivity of 3.0 g/l/h. Lactate dehydrogenase (LDH) expression profile in these different media was studied which resulted in appearance of additional LDH isoform produced by cells when they were grown in HSYE supplemented with (NH4)2HPO4. The additional LDH appears to be L-LDH contributing to production of L-lactic acid in the fermented broth. This is totally new information in the lactic acid fermentation and could be very useful to industries engaged in D-lactic acid production. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Adição de ácidos orgânicos e húmicos em Latossolos e adsorção de fosfato Addition of organic and humic acids to Latosols and phosphate adsorption effects

    Directory of Open Access Journals (Sweden)

    F. V. Andrade

    2003-12-01

    Full Text Available A matéria orgânica pode diminuir a adsorção/precipitação de fosfato (A/PP pela liberação de ácidos orgânicos, que competem pelos sítios de adsorção, ou pela formação de compostos com o fosfato na solução do solo e, ou, formação de complexos com Al e Fe, reduzindo a A/PP. O objetivo deste trabalho foi avaliar a redução na A/PP em Latossolos, pela adição de ácidos orgânicos: ácido cítrico (AC, oxálico (AO, salicílico (AS - e de ácidos húmicos (AH. Foram utilizadas amostras de um Latossolo Vermelho textura muito argilosa - (LV e um Latossolo Vermelho-Amarelo textura franco-argilo-arenosa - (LVA. Amostras de 2,5 cm³ de TFSA dos solos foram colocadas em erlenmeyer onde foram adicionados: fósforo (K2HPO4 e, ou, ácidos orgânicos ou húmicos, de acordo com a forma de aplicação (fosfato antes, junto e depois da aplicação do ácido, nas doses da relação molar ácido orgânico/P variando de 0 a 2:1. As doses dos ácidos húmicos variaram de 0 a 89,28 mg cm-3, equivalendo à adubação orgânica de 0 a 40 t ha-1 de material orgânico. O efeito dos ácidos orgânicos/ácidos húmicos na redução da A/PP nos dois solos seguiu a seguinte ordem: AC > AO > AH > AS. A forma de adição dos ácidos influenciou a A/PP em ambos os solos. No LV, a aplicação de fosfato e ácidos orgânicos ou ácidos húmicos juntos (FJA causou a maior redução na A/PP, indicando que deve ter ocorrido a ligação entre fosfato e ácidos. No LVA, a aplicação de fosfato depois dos ácidos orgânicos ou ácidos húmicos (FDA causou a maior redução na A/PP, indicando ter ocorrido bloqueio dos sítios de adsorção pelos ácidos.Organic matter can reduce P adsorption/precipitation (PA/P by: release of organic acids which compete for phosphate adsorption sites; trough the formation of P- compounds in the soil solution; and by building complexes with Fe and Al and thus decreasing PA/P. The aim of this study was to evaluate the PA/P in Oxisols

  3. Solid-State Fermentation Reduces Phytic Acid Level, Improves the Profi le of Myo-Inositol Phosphates and Enhances the Availability of Selected Minerals in Flaxseed Oil Cake

    Directory of Open Access Journals (Sweden)

    Robert Duliński

    2017-01-01

    Full Text Available Flaxseed oil cake was subjected to fermentation with Rhizopus oligosporus (DSM 1964 a nd ATCC 64063, and the phytate (InsP6 content, myo-inositol phosphate profi le and in vitro bioavailability of essential minerals were studied. Flaxseed oil cake had a phytate mass frac tion of 13.9 mg/g. A 96-hour fermentation of fl axseed oil cake by R. oligo sporus DSM 1964 and R. oligosporus ATCC 64063 decreased the InsP6 content by 48 and 33 %, respectively. The strains had diff erent phytate-degrading activities: fermentation of fl axseed oil cake with R. oligosporus DSM 1964 was more advantageous, yielding InsP3-5 as a predominating myo-inositol compound, while fermentation with R. oligosporus ATCC 64603 produced predominantly InsP5-6. Solid-state fermentation of fl axseed o il cake enhanced in vitro bioavailability of calcium by 14, magnesium by 3.3 and phosphorus by 2–4 %.

  4. {sup 26}Al-containing acidic and basic sodium aluminum phosphate preparation and use in studies of oral aluminum bioavailability from foods utilizing {sup 26}Al as an aluminum tracer

    Energy Technology Data Exchange (ETDEWEB)

    Yokel, Robert A. [College of Pharmacy, 511C Pharmacy Building 725 Rose Street, University of Kentucky Medical Center, Lexington, KY 40536-0082 (United States) and Graduate Center for Toxicology, University of Kentucky, Lexington, KY 40536-0305 (United States)]. E-mail: ryokel@email.uky.edu; Urbas, Aaron A. [Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055 (United States); Lodder, Robert A. [College of Pharmacy, 511C Pharmacy Building 725 Rose Street, University of Kentucky Medical Center, Lexington, KY 40536-0082 (United States); Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055 (United States); Selegue, John P. [Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055 (United States); Florence, Rebecca L. [College of Pharmacy, 511C Pharmacy Building 725 Rose Street, University of Kentucky Medical Center, Lexington, KY 40536-0082 (United States)

    2005-04-01

    We synthesized {sup 26}Al-containing acidic and basic (alkaline) sodium aluminum phosphates (SALPs) which are FDA-approved leavening and emulsifying agents, respectively, and used them to determine the oral bioavailability of aluminum incorporated in selected foods. We selected applicable methods from published syntheses (patents) and scaled them down ({approx}3000- and 850-fold) to prepare {approx}300-400 mg of each SALP. The {sup 26}Al was incorporated at the beginning of the syntheses to maximize {sup 26}Al and {sup 27}Al equilibration and incorporate the {sup 26}Al in the naturally-occurring Al-containing chemical species of the products. Near infrared spectroscopy (NIR) and X-ray powder diffraction (XRD) were used to characterize the two SALP samples and some intermediate samples. Multi-elemental analysis (MEA) was used to determine Na, Al and P content. Commercial products were included for comparison. Satisfactory XRD analyses, near infrared spectra and MEA results confirmed that we synthesized acidic and basic SALP, as well as some of the syntheses intermediates. The {sup 26}Al-containing acidic and basic SALPs were incorporated into a biscuit material and a processed cheese, respectively. These were used in oral bioavailability studies conducted in rats in which the {sup 26}Al present in blood after its oral absorption was quantified by accelerator mass spectrometry. The results showed oral Al bioavailability from acidic SALP in biscuit was {approx}0.02% and from basic SALP in cheese {approx}0.05%, lower than our previous determination of Al bioavailability from drinking water, {approx}0.3%. Both food and water can appreciably contribute to the Al absorbed from typical human Al intake.

  5. Isolation and structural studies of phosphate-containing oligosaccharides from alkaline and acid hydrolysates of Streptococcus pneumoniae type 6B capsular polysaccharide

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Dam, J.E.G. van; Breg, J.N.; Komen, R.; Kamerling, J.P.

    1989-01-01

    The capsular polysaccharide of Streptococcus pneumoniae serotype 6B [->2)-α-D-Galp-(1->3)-α-D-Glcp-(1->3)-α-L-Rhap-(1->4)-D-RibOH-(5-P->n was depolymerised under alkaline (NaOH) and acidic (HF) conditions. The former treatment yielded, as the major component,

  6. Purification of acidic phosphatase from mustard seedlings

    OpenAIRE

    sprotocols

    2014-01-01

    ### INTRODUCTION Phosphate esters are widely distributed in any organism. Nucleic acids, metabolic intermediates like glucose-6-phosphate, energy-rich substrates (AMP, creatine phosphate) are some obvious examples. While many metabolic intermediates are activated through the transfer of phosphate groups (e.g., by kinases) it is equally important that phosphate esters can also be rapidly broken down. The hydrolytic removal of phosphate groups from phosphoesters is catalyzed by phosphatases...

  7. 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...

  8. Regulation of resin acid synthesis in Pinus densiflora by differential transcription of genes encoding multiple 1-deoxy-D-xylulose 5-phosphate synthase and 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase genes.

    Science.gov (United States)

    Kim, Yeon-Bok; Kim, Sang-Min; Kang, Min-Kyoung; Kuzuyama, Tomohisa; Lee, Jong Kyu; Park, Seung-Chan; Shin, Sang-Chul; Kim, Soo-Un

    2009-05-01

    Pinus densiflora Siebold et Zucc. is the major green canopy species in the mountainous area of Korea. To assess the response of resin acid biosynthetic genes to mechanical and chemical stimuli, we cloned cDNAs of genes encoding enzymes involved in the 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway (1-deoxy-d-xylulose 5-phosphate synthase (PdDXS), 1-deoxy-d-xylulose 5-phosphate reductoisomerase (PdDXR) and 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (PdHDR)) by the rapid amplification of cDNA ends (RACE) technique. In addition, we cloned the gene encoding abietadiene synthase (PdABS) as a marker for the site of pine resin biosynthesis. PdHDR and PdDXS occurred as two gene families. In the phylogenetic trees, PdDXSs, PdDXR and PdHDRs each formed a separate clade from their respective angiosperm homologs. PdDXS2, PdHDR2 and PdDXR were most actively transcribed in stem wood, whereas PdABS was specifically transcribed. The abundance of PdDXS2 transcripts in wood in the resting state was generally 50-fold higher than the abundance of PdDXS1 transcripts, and PdHDR2 transcripts were more abundant by an order of magnitude in wood than in other tissues, with the ratio of PdHDR2 to PdHDR1 transcripts in wood being about 1. Application of 1 mM methyl jasmonate (MeJA) selectively enhanced the transcript levels of PdDXS2 and PdHDR2 in wood. The ratios of PdDXS2 to PdDXS1 and PdHDR2 to PdHDR1 reached 900 and 20, respectively, on the second day after MeJA treatment, whereas the transcript level of PdABS increased twofold by 3 days after MeJA treatment. Wounding of the stem differentially enhanced the transcript ratios of PdDXS2 to PdDXS1 and PdHDR2 to PdHDR1 to 300 and 70, respectively. The increase in the transcript levels of the MEP pathway genes in response to wounding was accompanied by two orders of magnitude increase in PdABS transcripts. These observations indicated that resin acid biosynthesis activity, represented by PdABS transcription, was correlated

  9. Generation of nicotinic acid adenine dinucleotide phosphate and cyclic ADP-ribose by glucagon-like peptide-1 evokes Ca2+ signal that is essential for insulin secretion in mouse pancreatic islets.

    Science.gov (United States)

    Kim, Byung-Ju; Park, Kwang-Hyun; Yim, Chang-Yeol; Takasawa, Shin; Okamoto, Hiroshi; Im, Mie-Jae; Kim, Uh-Hyun

    2008-04-01

    Glucagon-like peptide-1 (GLP-1) increases intracellular Ca(2+) concentrations ([Ca(2+)](i)), resulting in insulin secretion from pancreatic beta-cells. The molecular mechanism(s) of the GLP-1-mediated regulation of [Ca(2+)](i) was investigated. GLP-1-induced changes in [Ca(2+)](i) were measured in beta-cells isolated from Cd38(+/+) and Cd38(-/-) mice. Calcium-mobilizing second messengers were identified by measuring levels of nicotinic acid adenine dinucleotide phosphate (NAADP) and cyclic ADP-ribose (ADPR), using a cyclic enzymatic assay. To locate NAADP- and cyclic ADPR-producing enzyme(s), cellular organelles were separated using the sucrose gradient method. A GLP-1-induced [Ca(2+)](i) increase showed a cooperative Ca(2+) signal, i.e., an initial [Ca(2+)](i) rise mediated by the action of NAADP that was produced in acidic organelles and a subsequent long-lasting increase of [Ca(2+)](i) by the action of cyclic ADPR that was produced in plasma membranes and secretory granules. GLP-1 sequentially stimulated production of NAADP and cyclic ADPR in the organelles through protein kinase A and cAMP-regulated guanine nucleotide exchange factor II. Furthermore, the results showed that NAADP production from acidic organelles governed overall Ca(2+) signals, including insulin secretion by GLP-1, and that in addition to CD38, enzymes capable of synthesizing NAADP and/or cyclic ADPR were present in beta-cells. These observations were supported by the study with Cd38(-/-) beta-cells, demonstrating production of NAADP, cyclic ADPR, and Ca(2+) signal with normal insulin secretion stimulated by GLP-1. Our findings demonstrate that the GLP-1-mediated Ca(2+) signal for insulin secretion in pancreatic beta-cells is a cooperative action of NAADP and cyclic ADPR spatiotemporally formed by multiple enzymes.

  10. Phosphate fertilizer and weed control effects on growth and yield of ...

    African Journals Online (AJOL)

    The effect of phosphate fertilizer and weed control on yield and yield components of field pea (Pisum sativum L.) were studied on acidic Nitisols of farmers' fields of Welmera Woreda, West Shoa. Factorial combinations of four levels of phosphate fertilizer (0, 10, 20 and 30 kg P ha-1) as triple super-phosphate (TSP) and two ...

  11. Plant Growth Promotion Induced by Phosphate Solubilizing Endophytic Pseudomonas Isolates

    Directory of Open Access Journals (Sweden)

    Nicholas eOtieno

    2015-07-01

    Full Text Available The use of plant growth promoting bacterial inoculants as live microbial biofertilisers provides a promising alternative to chemical fertilisers and pesticides. Inorganic phosphate solubilisation is one of the major mechanisms of plant growth promotion by plant associated bacteria. This involves bacteria releasing organic acids into the soil which solubilise the phosphate complexes converting them into ortho-phosphate which is available for plant up-take and utilisation. The study presented here describes the ability of endophytic bacterial isolates to produce gluconic acid, solubilise insoluble phosphate and stimulate the growth of Pea plants (Pisum sativum. This study also describes the genetic systems within three of these endophyte isolates thought to be responsible for their effective phosphate solubilising abilities. The results showed that many of the endophytic isolates produced gluconic acid (14-169 mM and have moderate to high phosphate solubilisation capacities (~ 400-1300 mg L-1. When inoculated to Pea plants grown in sand/soil under soluble phosphate limiting conditions, the endophyte isolates that produced medium to high levels of gluconic acid also displayed enhanced plant growth promotion effects.

  12. 1,2-Dibromo-4-(1,2-dibromoethyl)-cyclohexane and tris(methylphenyl) phosphate cause significant effects on development, mRNA expression, and circulating bile acid concentrations in chicken embryos

    Energy Technology Data Exchange (ETDEWEB)

    Crump, Doug, E-mail: doug.crump@ec.gc.ca [National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3 (Canada); Porter, Emily; Egloff, Caroline; Williams, Kim L.; Letcher, Robert J.; Gauthier, Lewis T. [National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3 (Canada); Kennedy, Sean W. [National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3 (Canada); Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5 (Canada)

    2014-06-15

    1,2-Dibromo-4-(1,2-dibromoethyl)-cyclohexane (DBE-DBCH; formerly abbreviated as TBECH) and tris(methylphenyl) phosphate (TMPP; formerly abbreviated as TCP) are additive flame retardants that are detected in the environment and biota. A recent avian in vitro screening study of 16 flame retardants identified DBE-DBCH and TMPP as important chemicals for follow-up in ovo evaluation based on their effects on cytotoxicity and mRNA expression in avian hepatocytes. In this study, technical mixtures of DBE-DBCH and TMPP were injected into the air cell of chicken embryos at concentrations ranging from 0 to 54,900 ng/g and from 0 to 261,400 ng/g, respectively, to determine effects on pipping success, development, hepatic mRNA expression, thyroid hormone levels, and circulating bile acid concentrations. Both compounds were detectable in embryos at pipping and the β-DBE-DBCH isomer was depleted more rapidly than the α-isomer in tissue samples. DBE-DBCH had limited effects on the endpoints measured, with the exception of the up-regulation of two phase I metabolizing enzymes, CYP3A37 and CYP2H1. TMPP exposure caused embryonic deformities, altered growth, increased liver somatic index (LSI) and plasma bile acid concentrations, and altered mRNA expression levels of genes associated with xenobiotic and lipid metabolism and the thyroid hormone pathway. Overall, TMPP elicited more adverse molecular and phenotypic effects than DBE-DBCH albeit at concentrations several orders of magnitude greater than those detected in the environment. The increase in plasma bile acid concentrations was a useful phenotypic anchor as it was associated with a concomitant increase in LSI, discoloration of the liver tissue, and modulation of hepatic genes involved with xenobiotic and lipid metabolism. - Highlights: • DBE-DBCH and TMPP are not embryolethal to chicken embryos. • TMPP caused deformities, morphometric alterations, and increased plasma bile acids. • DBE-DBCH and TMPP altered mRNA levels

  13. Effect of phosphate on removal of humic substances by aluminum sulfate coagulant.

    Science.gov (United States)

    Cheng, Wen Po; Chi, Fung Hwa; Yu, Ruey Fang

    2004-04-01

    The presence of humic acid may change the way phosphate is absorbed or stabilized by soil and how it influences the growth of plants. The binding of phosphate with the humic substance requires bridging between phosphate ions and humic acid by metal ions, such as aluminum or iron ions. The bridging reaction can take place in peat and allophane soil under acidic conditions, altering the effectiveness of the phosphate in soil. Whether ternary phosphate-metal-HA complexes are actually formed has not yet been verified. This study considers variation in fluorescence intensity (FI) under various coagulation conditions to assess the mechanism by which humic acids and phosphate react with aluminum ions. A bond between the functional group of the humic acid and the electron-releasing group of the phosphate will enhance the florescent intensity of humic acids. Consequently the removal efficiency of humic acid, measured by florescence, declines as the phosphate concentration increases at low pH. This observation suggests that at low coagulation pH, the positively charged aluminum species can be used to bridge between the phosphate ion and the humic acid molecules.

  14. Effects of mutagenesis of aspartic acid residues in the putative phosphoribosyl diphosphate binding site of Escherichia coli phosphoribosyl diphosphate synthetase on metal ion specificity and ribose-5-phosphate binding

    DEFF Research Database (Denmark)

    Willemoës, Martin; Nilsson, Dan; Hove-Jensen, Bjarne

    1996-01-01

    The three conserved aspartic acid residues of the 5-phospho-d-ribosyl a-1-diphosphate binding site (213-GRDCVLVDDMIDTGGT-228) of Escherichia coli phosphoribosyl diphosphate synthetase were studied by analysis of the mutant enzymes D220E, D220F, D221A, D224A, and D224S. The mutant enzymes showed...... an increase in KM for ribose 5-phosphate in the presence of at least one of the divalent metal ions Mg2+, Mn2+, Co2+, or Cd2+, with the most dramatic changes revealed by the D220E and D220F enzymes in the presence of Co2+ and the D221A enzyme in the presence of Mn2+ or Co2+. The D220F and D221A enzymes both...... showed large decreases in Vapp in the presence of the various divalent metal ions, except for the D221A enzyme in the presence of Co2+. Vapp of the D220E enzyme was similar to that of the wild-type enzyme in the presence of Mg2+, Mn2+, or Cd2+, whereas the Vapp was increased in the presence of Co2+. Vapp...

  15. Biomechanical stability of a bioabsorbable self-retaining polylactic acid/nano-sized β-tricalcium phosphate cervical spine interbody fusion device in single-level anterior cervical discectomy and fusion sheep models

    Science.gov (United States)

    Cao, Lu; Duan, Ping-Guo; Li, Xi-Lei; Yuan, Feng-Lai; Zhao, Ming-Dong; Che, Wu; Wang, Hui-Ren; Dong, Jian

    2012-01-01

    Purpose The aim of this study was to investigate the biomechanical stability provided by a novel, polylactic acid/nano-sized, β-tricalcium phosphate, bioabsorbable, self-retaining cervical fusion cage (BCFC). Methods Quasistatic nonconstraining torques (maximum 1.5 NM) induced flexion, extension, lateral bending (±1.5 NM), and axial rotation (±1.5 NM) on 32 sheep cervical spines (C2–C5). The motion segment C3–C4 was first tested intact; the following groups were tested after complete discectomy: autologous tricortical iliac crest bone graft, Medtronic–Wego polyetheretherketone (PEEK) cage, Solis PEEK cage, and BCFC. The autologous bone graft group was tested with an anterior plate. The mean range of motion (ROM) was calculated from the load-displacement curves. Results BCFC significantly decreased ROM in lateral bending and axial rotation compared to other implants, and no significant difference in ROM between two types of PEEK cages and BCFC could be observed in flexion and extension. Anterior cervical plate (ACP) significantly decreased ROM in flexion and extension, but no significant difference in ROM between BCFC and bone graft plus ACP could be determined in lateral bending and axial rotation. Conclusion The BCFC device showed better stability to autologous tricortical iliac crest bone graft and PEEK cages in single-level anterior cervical discectomy and fusion models and thus may be a potential alternative to the current PEEK cages. PMID:23226018

  16. Biomechanical stability of a bioabsorbable self-retaining polylactic acid/nano-sized β-tricalcium phosphate cervical spine interbody fusion device in single-level anterior cervical discectomy and fusion sheep models.

    Science.gov (United States)

    Cao, Lu; Duan, Ping-Guo; Li, Xi-Lei; Yuan, Feng-Lai; Zhao, Ming-Dong; Che, Wu; Wang, Hui-Ren; Dong, Jian

    2012-01-01

    The aim of this study was to investigate the biomechanical stability provided by a novel, polylactic acid/nano-sized, β-tricalcium phosphate, bioabsorbable, self-retaining cervical fusion cage (BCFC). Quasistatic nonconstraining torques (maximum 1.5 NM) induced flexion, extension, lateral bending (±1.5 NM), and axial rotation (±1.5 NM) on 32 sheep cervical spines (C2-C5). The motion segment C3-C4 was first tested intact; the following groups were tested after complete discectomy: autologous tricortical iliac crest bone graft, Medtronic-Wego polyetheretherketone (PEEK) cage, Solis PEEK cage, and BCFC. The autologous bone graft group was tested with an anterior plate. The mean range of motion (ROM) was calculated from the load-displacement curves. BCFC significantly decreased ROM in lateral bending and axial rotation compared to other implants, and no significant difference in ROM between two types of PEEK cages and BCFC could be observed in flexion and extension. Anterior cervical plate (ACP) significantly decreased ROM in flexion and extension, but no significant difference in ROM between BCFC and bone graft plus ACP could be determined in lateral bending and axial rotation. The BCFC device showed better stability to autologous tricortical iliac crest bone graft and PEEK cages in single-level anterior cervical discectomy and fusion models and thus may be a potential alternative to the current PEEK cages.

  17. Phosphate control in dialysis

    Directory of Open Access Journals (Sweden)

    Cupisti A

    2013-10-01

    Full Text Available Adamasco Cupisti,1 Maurizio Gallieni,2 Maria Antonietta Rizzo,2 Stefania Caria,3 Mario Meola,4 Piergiorgio Bolasco31Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy; 2Nephrology and Dialysis Unit, San Carlo Borromeo Hospital, Milan, Italy; 3Territorial Department of Nephrology and Dialysis, ASL Cagliari, Italy; 4Sant'Anna School of Advanced Studies, University of Pisa, Pisa, ItalyAbstract: Prevention and correction of hyperphosphatemia is a major goal of chronic kidney disease–mineral and bone disorder (CKD–MBD management, achievable through avoidance of a positive phosphate balance. To this aim, optimal dialysis removal, careful use of phosphate binders, and dietary phosphate control are needed to optimize the control of phosphate balance in well-nourished patients on a standard three-times-a-week hemodialysis schedule. Using a mixed diffusive–convective hemodialysis tecniques, and increasing the number and/or the duration of dialysis tecniques are all measures able to enhance phosphorus (P mass removal through dialysis. However, dialytic removal does not equal the high P intake linked to the high dietary protein requirement of dialysis patients; hence, the use of intestinal P binders is mandatory to reduce P net intestinal absorption. Unfortunately, even a large dose of P binders is able to bind approximately 200–300 mg of P on a daily basis, so it is evident that their efficacy is limited in the case of an uncontrolled dietary P load. Hence, limitation of dietary P intake is needed to reach the goal of neutral phosphate balance in dialysis, coupled to an adequate protein intake. To this aim, patients should be informed and educated to avoid foods that are naturally rich in phosphate and also processed food with P-containing preservatives. In addition, patients should preferentially choose food with a low P-to-protein ratio. For example, patients could choose egg white or protein from a vegetable source

  18. Effects of Hyaluronic Acid and Hydroxyapatite/Beta-tricalcium Phosphate in Combination on Bone Regeneration of a Critical-size Defect in an Experimental Model.

    Science.gov (United States)

    Diker, Nurettin; Gulsever, Serap; Koroglu, Taner; Yilmaz Akcay, Eda; Oguz, Yener

    2018-02-12

    Hyaluronic acid (HyA) is an outstanding new product in the field of oral and maxillofacial surgery. The aim of this study was to evaluate the effects of HyA on bone regeneration in critical-size calvarial defects. Twenty-four female Sprague-Dawley rats were used in the present study. In each rat, 4 critical-size defects received different treatments: no treatment (control); HyA; Graft; and HyA + Graft combination. New bone formation, defect closure, inflammation, vascular proliferation, immature bone formation, mature bone formation, and bone marrow existence were investigated based on histological findings. The healing parameters related to bone formation (new bone formation, defect closure, immature bone formation) were significantly higher in the HyA group compared with the control group. However, HyA alone was unable to induce sufficient bone regeneration compared with treatments involving graft materials (Graft and HyA + Graft). In the Graft and HyA + Graft groups, prominent enhancement of all healing parameters was noted. The present results demonstrate that HyA alone did not adequately enhance bone regeneration in critical-size defects. Moreover, addition of HyA to a biphasic alloplastic graft material did not result in improved regeneration compared with the graft material alone.

  19. Surface-grafting of phosphates onto a polymer for potential biomimetic functionalization of biomaterials

    Science.gov (United States)

    Ko, Young Gun; Ma, Peter X.

    2009-01-01

    In the human body, phosphate groups play important roles in signaling and the biological functions of proteins and peptides. Despite the importance of phosphate groups, polymer surfaces have not been directly grafted with phosphate groups by chemical reactions because the usual organic solvents used to graft phosphate groups can dissolve or swell polymers. We focused this study on grafting phosphate groups onto a poly(ethylene-co-acrylic acid) (PEAA) surface in an aqueous solution. O-phospho L-serine and O-phosphoethanolamine were grafted on PEAA surfaces to introduce phosphate groups by activating carboxylic acid groups of PEAA using N-hydroxysuccinimide (NHS) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) in an aqueous environment. X-ray photoelectron spectroscopy (XPS) was used to elucidate the process by which surface grafting occurs and the process that the phosphate group is cleaved into a phosphate ion and a hydrolyzed molecule at high pH. It was found that under appropriate reaction conditions the phosphate groups could be successfully grafted on the polymer surfaces. The phosphate-grafted polymer surfaces showed lower water contact angles than the initial polymer surfaces likely due to their highly mobile and hydrophilic phosphate-chains. This work demonstrates a technique to successfully graft phosphate groups onto organic polymer surfaces in a biocompatible aqueous environment, which may open new avenues to functionalizing synthetic polymeric and natural macromolecule derived biomaterials. PMID:18977490

  20. Copper scandium zirconium phosphate

    DEFF Research Database (Denmark)

    Bond, Andrew David; Warner, Terence Edwin

    2013-01-01

    components. The [Sc(III)Zr(IV)(PO(4))(3)](2-) framework is composed of corner-sharing Sc/ZrO(6) octahedra and PO(4) tetrahedra. The Sc and Zr atoms are disordered on one atomic site on a crystallographic threefold axis. The P atom of the phosphate group lies on a crystallographic twofold axis. Nonframework...

  1. Sodium Phosphate Rectal

    Science.gov (United States)

    ... liquid using a measuring spoon. Then replace the bottle cap.To use the sodium phosphate enema, follow these steps: Remove the protective shield from the tip of the enema. Lie down on ... insert the enema bottle into your rectum with the tip pointing toward ...

  2. Glucose-6-phosphate dehydrogenase deficiency

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000528.htm Glucose-6-phosphate dehydrogenase deficiency To use the sharing features on this page, please enable JavaScript. Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a condition ...

  3. Phosphate Surface Treatments on Steel.

    Science.gov (United States)

    ALKALI METAL COMPOUNDS, BATHS, CHEMICAL COMPOSITION, COATINGS, DOCUMENTS, IONS, IRON, MATERIALS, METALS, PATENTS, PHOSPHATE COATINGS, PHOSPHATES ...RESPONSE, SPRAYS, STEEL, SURFACE FINISHING, SURFACES, TIME, WEIGHT, ZINC , ZINC COATINGS, ZINC COMPOUNDS

  4. Analysis of phosphate esters in plant material. Extraction and purification.

    Science.gov (United States)

    Isherwood, F A; Barrett, F C

    1967-09-01

    1. A critical study was made of the quantitative extraction of nucleotide and sugar phosphates from plant tissue by either boiling aqueous ethanol or cold trichloroacetic acid. The effect of the extraction technique on the inactivation of the enzymes in the plant tissue and the possibility of adsorption of the phosphate esters on the cell wall were especially considered. 2. In the recommended method the plant tissue was frozen in liquid nitrogen, ground to a powder and then blended with cold aqueous trichloroacetic acid containing 8-hydroxyquinoline to prevent adsorption. 3. The extract contained large amounts of trichloroacetic acid, cations, chloride, sugars, amino acids, hydroxy organic acids, phytic acid, orthophosphoric acid and high-molecular-weight material including some phosphorus-containing compounds. All of these were removed as they were liable to interfere with the chromatographic or enzymic assay of the individual nucleotide or sugar phosphates. 4. The procedure was as follows: the last traces of trichloroacetic acid were extracted with ether after the solution had been passed through a column of Dowex AG 50 in the hydrogen form to remove all cations. High-molecular-weight compounds were removed by ultrafiltration and low-molecular-weight solutes by a two-stage chromatography on cellulose columns with organic solvents. In the first stage, sugars, amino acids, chloride and phytic acid were separated by using a basic solvent (propan-1-ol-water-aqueous ammonia) and, in the second stage, the organic acids and orthophosphoric acid were separated by using an acidic solvent (di-isopropyl ether-formic acid-2-methylpropan-2-ol-water). The final solution of nucleotide and sugar phosphates was substantially free from other solutes and was suitable for the detection of individual phosphate esters by either chromatography or enzymic assay. 5. The recovery of d-glucose 6-phosphate or adenosine 5'-triphosphate added to a trichloroacetic acid extract simulating that

  5. Phosphate removal from wastewater using red mud.

    Science.gov (United States)

    Huang, Weiwei; Wang, Shaobin; Zhu, Zhonghua; Li, Li; Yao, Xiangdong; Rudolph, Victor; Haghseresht, Fouad

    2008-10-01

    Red mud, a waste residue of alumina refinery, has been used to develop effective adsorbents to remove phosphate from aqueous solution. Acid and acid-thermal treatments were employed to treat the raw red mud. The effects of different treatment methods, pH of solution and operating temperature on adsorption have been examined in batch experiments. It was found that all activated red mud samples show higher surface area and total pore volume as well as higher adsorption capacity for phosphate removal. The red mud with HCl treatment shows the highest adsorption capacity among all the red mud samples, giving adsorption capacity of 0.58 mg P/g at pH 5.5 and 40 degrees C. The adsorption capacity of the red mud adsorbents decreases with increase of pH. At pH 2, the red mud with HCl treatment exhibits adsorption of 0.8 mg P/g while the adsorption can be lowered to 0.05 mg P/g at pH 10. However, the adsorption is improved at higher temperature by increasing 25% from 30 to 40 degrees C. The kinetic studies of phosphate adsorption onto red mud indicate that the adsorption mainly follows the parallel first-order kinetics due to the presence of two acidic phosphorus species, H(2)PO(4)(-) and HPO(4)(2-). An analysis of the adsorption data indicates that the Freundlich isotherm provides a better fitting than the Langmuir model.

  6. Plant growth promotion induced by phosphate solubilizing endophytic Pseudomonas isolates

    Science.gov (United States)

    Oteino, Nicholas; Lally, Richard D.; Kiwanuka, Samuel; Lloyd, Andrew; Ryan, David; Germaine, Kieran J.; Dowling, David N.

    2015-01-01

    The use of plant growth promoting bacterial inoculants as live microbial biofertilizers provides a promising alternative to chemical fertilizers and pesticides. Inorganic phosphate solubilization is one of the major mechanisms of plant growth promotion by plant associated bacteria. This involves bacteria releasing organic acids into the soil which solubilize the phosphate complexes converting them into ortho-phosphate which is available for plant up-take and utilization. The study presented here describes the ability of endophytic bacteria to produce gluconic acid (GA), solubilize insoluble phosphate, and stimulate the growth of Pisum sativum L. plants. This study also describes the genetic systems within three of these endophyte strains thought to be responsible for their effective phosphate solubilizing abilities. The results showed that many of the endophytic strains produced GA (14–169 mM) and have moderate to high phosphate solubilization capacities (~400–1300 mg L−1). When inoculated into P. sativum L. plants grown in soil under soluble phosphate limiting conditions, the endophytes that produced medium-high levels of GA displayed beneficial plant growth promotion effects. PMID:26257721

  7. A kinetic study of phosphate adsorption by boehmite.

    Science.gov (United States)

    Tang, W P; Shima, O; Ookubo, A; Ooi, K

    1997-02-01

    Rates of phosphate adsorption to PT-A (a new type of aluminium oxide hydroxide) and ALG (aluminum hydroxide gel) from a pH 3 phosphate solution were measured by a batch method. Phosphate uptake progressed mainly by the adsorption mechanism for PT-A, but dissolution of aluminum and precipitation of aluminum phosphate took place in addition to phosphate adsorption for ALG. The intraparticle diffusivities (Dp'S) of phosphate were evaluated from the time courses of adsorption using the model of pore diffusion with a Freundlich-type adsorption isotherm. The Dp values were approximately 7 x 10(-7) cm2 S-1 for PT-A and 1 x 10(-6) cm2 s(-1) for ALG. The tortuosity factors calculated from a model of parallel plate pore were 5.1 for PT-A and 6.7 for ALG; these values resembled those for porous inorganic ion exchangers. The adsorption rates are high enough for each of the samples to be utilized as a phosphate adsorbent to prevent hyperphosphatemia in patients on chronic dialysis. PT-A is favored as a phosphate adsorbent because of its high chemical stability against acid.

  8. Fluorimetric determination of carbamoyl phosphate

    NARCIS (Netherlands)

    Wanders, R. J.; van Roermund, C.; Lof, C.; Meijer, A. J.

    1983-01-01

    A simple fluorimetric assay for the determination of carbamoyl phosphate in tissue extracts is described. In the assay, production of ATP from carbamoyl phosphate and ADP by carbamate kinase is coupled to the formation of NADPH, using glucose, hexokinase, NADP+, and glucose-6-phosphate

  9. Practical application of phosphate treatment

    Energy Technology Data Exchange (ETDEWEB)

    Caravaggio, Mike [Integrated Chemistry Solutions Pte. Ltd., Singapore (Singapore)

    2011-05-15

    Phosphate treatment has been applied to subcritical fossil power boilers for well over half a century, as well as being used frequently in heat recovery steam generators. The use of this treatment has evolved over the decades, with the operating sodium to phosphate ratio being the defining factor for the evolution of the treatment. The evolving prescribed sodium to phosphate ratios have been based on the scientific research results and operating experience available at the time, and in the latest EPRI Guidelines issued in 2004 are set at a minimum sodium to phosphate ratio of 3:1, with provision to add up to 1 mg . L{sup -1} of additional free caustic. The ratio limitation has always been set in an effort to minimize the potential for corrosion caused by the potential misapplication of the treatment. Typically, the operating ranges for phosphate treatments are depicted on an x-y plot with the x-axis the phosphate concentration and the y-axis the corrected pH value based on the maximum sodium to phosphate ratio allowed for by the treatment. These operating range plots define the theoretical operating range of a phosphate treatment. This paper briefly discusses the origin of the current phosphate control limits in the EPRI Guidelines, discusses phosphate chemistry, outlines the limitations involved when applying a phosphate treatment and provides additional practical guidance for overcoming these limitations and minimizing the potential for corrosion induced by the incorrect application of a phosphate treatment. (orig.)

  10. Facile enzymatic synthesis of sugar 1-phosphates as substrates for phosphorylases using anomeric kinases.

    Science.gov (United States)

    Liu, Yuan; Nishimoto, Mamoru; Kitaoka, Motomitsu

    2015-01-12

    Three sugar 1-phosphates that are donor substrates for phosphorylases were produced at the gram scale from phosphoenolpyruvic acid and the corresponding sugars by the combined action of pyruvate kinase and the corresponding anomeric kinases in good yields. These sugar 1-phosphates were purified through two electrodialysis steps. α-D-Galactose 1-phosphate was finally isolated as crystals of dipotassium salts. α-D-Mannose 1-phosphate and 2-acetamido-2-deoxy-α-D-glucose 1-phosphate were isolated as crystals of bis(cyclohexylammonium) salts. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Immobilization of fission products in phosphate ceramic waste forms

    Energy Technology Data Exchange (ETDEWEB)

    Singh, D.; Wagh, A. [Argonne National Lab., IL (United States)

    1997-10-01

    Chemically bonded phosphate ceramics (CBPCs) have several advantages that make them ideal candidates for containing radioactive and hazardous wastes. In general, phosphates have high solid-solution capacities for incorporating radionuclides, as evidenced by several phosphates (e.g., monazites and apatites) that are natural analogs of radioactive and rare-earth elements. The phosphates have high radiation stability, are refractory, and will not degrade in the presence of internal heating by fission products. Dense and hard CBPCs can be fabricated inexpensively and at low temperature by acid-base reactions between an inorganic oxide/hydroxide powder and either phosphoric acid or an acid-phosphate solution. The resulting phosphates are extremely insoluble in aqueous media and have excellent long-term durability. CBPCs offer the dual stabilization mechanisms of chemical fixation and physical encapsulation, resulting in superior waste forms. The goal of this task is develop and demonstrate the feasibility of CBPCs for S/S of wastes containing fission products. The focus of this work is to develop a low-temperature CBPC immobilization system for eluted {sup 99}Tc wastes from sorption processes.

  12. Triphenyl phosphate allergy from spectacle frames

    DEFF Research Database (Denmark)

    Carlsen, L; Andersen, K E; Egsgaard, Helge

    1986-01-01

    A case of triphenyl phosphate allergy from spectacle frames is reported. Patch tests with analytical grade triphenyl phosphate, tri-m-cresyl phosphate, and tri-p-cresyl phosphate in the concentrations 5%, 0.5% and 0.05% pet. showed positive reactions to 0.05% triphenyl phosphate and 0.5% tri...... triphenyl phosphate allergy in our patient....

  13. 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...

  14. Renal phosphate handling: Physiology

    Directory of Open Access Journals (Sweden)

    Narayan Prasad

    2013-01-01

    Full Text Available Phosphorus is a common anion. It plays an important role in energy generation. Renal phosphate handling is regulated by three organs parathyroid, kidney and bone through feedback loops. These counter regulatory loops also regulate intestinal absorption and thus maintain serum phosphorus concentration in physiologic range. The parathyroid hormone, vitamin D, Fibrogenic growth factor 23 (FGF23 and klotho coreceptor are the key regulators of phosphorus balance in body.

  15. Selective separation of phosphate and fluoride from semiconductor wastewater.

    Science.gov (United States)

    Warmadewanthi, B; Liu, J C

    2009-01-01

    Hydrofluoric acid (HF) and phosphoric acid (H(3)PO(4)) are widely used in semiconductor industry for etching and rinsing purposes. Consequently, significant amount of wastewater containing phosphate and fluoride is generated. Selective separation of phosphate and fluoride from the semiconductor wastewater, containing 936 mg/L of fluoride, 118 mg/L of phosphate, 640 mg/L of sulfate, and 26.7 mg/L of ammonia, was studied. Chemical precipitation and flotation reactions were utilized in the two-stage treatment processes. The first-stage reaction involved the addition of magnesium chloride (MgCl(2)) to induce selective precipitation of magnesium phosphate. The optimal condition was pH 10 and molar ratio, [Mg(2 + )]/[(PO(4) (3-))], of 3:1, and 66.2% of phosphate was removed and recovered as bobierrite (Mg(3)(PO(4))(2).8H(2)O). No reaction was found between MgCl(2) and fluoride. Calcium chloride (CaCl(2)) was used in the second-stage reaction to induce precipitation of calcium fluoride and calcium phosphate. The optimum molar ratio, [Ca(2 + )]/[F(-)], was 0.7 at pH 10, and residual fluoride concentration of 10.7 mg/L and phosphate concentration of lower than 0.5 mg/L was obtained. Thermodynamic equilibrium was modeled with PHREEQC and compared with experimental results. Sodium dodecylsulfate (SDS) was an effective collector for subsequent solid-liquid removal via dispersed air flotation (DiAF). The study demonstrated that phosphate can be selectively recovered from the wastewater. Potential benefits include recovery of phosphate for reuse, lower required dosage of calcium for fluoride removal, and less amount of CaF(2) sludge.

  16. Oral phosphate binders: phosphate binding capacity of iron (III) hydroxide complexes containing saccharides and their effect on the urinary excretion of calcium and phosphate in rats.

    Science.gov (United States)

    Yamaguchi, T; Baxter, J G; Maebashi, N; Asano, T

    1999-09-01

    Phosphate binders that contain aluminum or calcium are frequently prescribed to treat hyperphosphatemia in patients with end-stage renal disease (ESRD), but an accumulation of aluminum can lead to encephalopathy, aluminum-related bone disease (ARBD) such as osteomalacia, anaemia, and resistance to erythropoietin, and calcium accumulation can lead to hypercalcaemia. High phosphate concentrations are reduced in vitro and in vivo by a phosphate adsorption pill, which is synthesized by hydrolyzing ferrous sulfate in the presence of saccharides, to form an iron (III)-saccharide complex that is acid resistant and binds phosphate greater than iron (III) hydroxide alone. Under in vitro conditions, containing 3.26 mg P/dL, the iron (III)-sucrose complex showed the highest phosphate adsorption capacity at pH 2 with artificial gastric juice, 58.9 mg P/g binder. For the 7 day in vivo study, 0% (Group 1), 1% (Group 2), 4% (Group 3), and 8% (Group 4) iron (III)-sucrose complex was admixed into the rodent chow by weight and fed to 15 male Wistar rats. The weight and volume of the feces and urine, and the calcium, iron, and phosphorus excretions in the feces and urine samples were monitored for any signs of irregularity. Total urine outflow was collected during a 24-h period to determine the amount of phosphate recovered, which indicates the ability of the phosphate binder to reduce gastrointestinal phosphate absorption. The fecal iron excretion was significantly effected by the amount of binder ingested throughout the study for Group 2 (p calcium excretion (mg/rat/24-h) significantly increased by the 7th day for Group 2 (p calcium containing phosphate-binding agents for combating hyperphosphataemia.

  17. Calcium-phosphate-osteopontin particles for caries control

    DEFF Research Database (Denmark)

    Schlafer, Sebastian; Birkedal, Henrik; Olsen, Jakob

    2016-01-01

    Caries is caused by acid production in biofilms on dental surfaces. Preventing caries therefore involves control of microorganisms and/or the acid produced. Here, calcium-phosphate-osteopontin particles are presented as a new approach to caries control. The particles are made by co......-precipitation and designed to bind to bacteria in biofilms, impede biofilm build-up without killing the microflora, and release phosphate ions to buffer bacterial acid production if the pH decreases below 6. Analysis of biofilm formation and pH in a five-species biofilm model for dental caries showed that treatment......H always remained above 5.5. Hence, calcium-phosphate-osteopontin particles show potential for applications in caries control....

  18. PHOSPHATE CRYSTALLURIA IN VARIOUS FORMS OF UROLITHIASIS AND POSSIBILITIES OF ITS PROGNOSTICATION IN PATIENTS WITH PHOSPHATE STONES

    Directory of Open Access Journals (Sweden)

    O. V. Konstantinova

    2017-01-01

    Full Text Available Purpose. Definition of types of crystalluria in various forms of urolithiasis and biochemical signs of phosphate crystals in the urine, while phosphate urolithiasis (infectious origin.Patients and methods. The study involved 144 patients with recurrent urolithiasis — 75 women and 69 men. Of these, 46 — diagnosed calculi with uric acid, 44 — calcium oxalate or mixed with a prevalence of calcium oxalate, in 54 — phosphate rocks (carbonate-apatite and/or struvite. The age of patients ranged from 21 to 74 years. 93 people have been under long-term, within 2–15 years, outpatient observation. The examination included the collection of anamnesis, general and microbiological analysis of urine, biochemical blood serum and urine on 10 indicators, reflecting renal function, state of the protein, water and electrolyte metabolism, uric acid metabolism, the chemical composition of the stone analysis.Results. It was found that in patients with calcium oxalate stones phosphaturia has been diagnosed in 2% of cases. And, along with calcium phosphate crystals they had oxalate crystals. In patients with phosphate urolithiasis phosphaturia observed in 96% of patients, in two patients (4% they determined except phosphates also oxalate salt in urine sediment. Patients with phosphate urolithiasis at occurrence of phosphate crystalluria have metabolic state changes: increased serum uric acid concentration from 0.322 ± 0.009 to 0.367 ± 0.018 mmol/l daily renal excretion of inorganic phosphate 23.94 ± 2.93 mmol/day to 32.12 ± 4.39 mmol/day, and reduced total calcium content in urine 6.61 ± 0.94 mmol/day to 3.37 ± 0.89 mmol/day. The results led to the following conclusion.Conclusion. Biochemical signs of occurrence of phosphate crystalluria in patients with stones of infectious origin can be: the approaching level of excretion in the urine of inorganic phosphates to 32,12 ± 4,39 mmol/day, serum uric acid concentration to 0,367 ± 0,018 mmol/l, and the

  19. Origin of Life and the Phosphate Transfer Catalyst.

    Science.gov (United States)

    Piast, Radosław W; Wieczorek, Rafał M

    2017-03-01

    In this paper, we revisit several issues relevant to origin-of-life research and propose a Phosphate Transfer Catalyst hypothesis that furthers our understanding of some of the key events in prebiotic chemical evolution. In the Phosphate Transfer Catalyst hypothesis, we assume the existence of hypothetical metallopeptides with phosphate transfer activity that use abundant polyphosphates as both substrates and energy sources. Nonspecific catalysis by this phosphate transfer catalyst would provide a variety of different products such as phosphoryl amino acids, nucleosides, polyphosphate nucleotides, nucleic acids, and aminoacylated nucleic acids. Moreover, being an autocatalytic set and metabolic driver at the same time, it could possibly replicate itself and produce a collective system of two polymerases; a nucleic acid able to catalyze peptide bond formation and a peptide able to polymerize nucleic acids. The genetic code starts at first as a system that reduces the energy barrier by bringing substrates (2'/3' aminoacyl-nucleotides) together, an ancestral form of the catalysis performed by modern ribosomes. Key Words: Origin of life-Prebiotic chemistry-Catalysis-Nucleic acids. Astrobiology 17, 277-285.

  20. Aluminum phosphate ceramics for waste storage

    Science.gov (United States)

    Wagh, Arun; Maloney, Martin D

    2014-06-03

    The present disclosure describes solid waste forms and methods of processing waste. In one particular implementation, the invention provides a method of processing waste that may be particularly suitable for processing hazardous waste. In this method, a waste component is combined with an aluminum oxide and an acidic phosphate component in a slurry. A molar ratio of aluminum to phosphorus in the slurry is greater than one. Water in the slurry may be evaporated while mixing the slurry at a temperature of about 140-200.degree. C. The mixed slurry may be allowed to cure into a solid waste form. This solid waste form includes an anhydrous aluminum phosphate with at least a residual portion of the waste component bound therein.

  1. Towards Phosphate Detection in Hydroponics Using Molecularly Imprinted Polymer Sensors.

    Science.gov (United States)

    Storer, Christopher S; Coldrick, Zachary; Tate, Daniel J; Donoghue, Jack Marsden; Grieve, Bruce

    2018-02-10

    An interdigitated electrode sensor was designed and microfabricated for measuring the changes in the capacitance of three phosphate selective molecularly imprinted polymer (MIP) formulations, in order to provide hydroponics users with a portable nutrient sensing tool. The MIPs investigated were synthesised using different combinations of the functional monomers methacrylic acid (MAA) and N -allylthiourea, against the template molecules diphenyl phosphate, triethyl phosphate, and trimethyl phosphate. A cross-interference study between phosphate, nitrate, and sulfate was carried out for the MIP materials using an inductance, capacitance, and resistance (LCR) meter. Capacitance measurements were taken by applying an alternating current (AC) with a potential difference of 1 V root mean square (RMS) at a frequency of 1 kHz. The cross-interference study demonstrated a strong binding preference to phosphate over the other nutrient salts tested for each formulation. The size of template molecule and length of the functional monomer side groups also determined that a short chain functional monomer in combination with a template containing large R-groups produced the optimal binding site conditions when synthesising a phosphate selective MIP.

  2. Solubility of Calcium Phosphate in Concentrated Dairy Effluent Brines.

    Science.gov (United States)

    Kezia, K; Lee, J; Zisu, B; Chen, G Q; Gras, S L; Kentish, S E

    2017-05-24

    The solubility of calcium phosphate in concentrated dairy brine streams is important in understanding mineral scaling on equipment, such as membrane modules, evaporators, and heat exchangers, and in brine pond operation. In this study, the solubility of calcium phosphate has been assessed in the presence of up to 300 g/L sodium chloride as well as lactose, organic acids, and anions at 10, 30, and 50 °C. As a neutral molecule, lactose has a marginal but still detectable effect upon calcium solubility. However, additions of sodium chloride up to 100 g/L result in a much greater increase in calcium solubility. Beyond this point, the concentrations of ions in the solution decrease significantly. These changes in calcium solubility can readily be explained through changes in the activity coefficients. There is little difference in calcium phosphate speciation between 10 and 30 °C. However, at 50 °C, the ratio of calcium to phosphate in the solution is lower than at the other temperatures and varies less with ionic strength. While the addition of sodium lactate has less effect upon calcium solubility than sodium citrate, it still has a greater effect than sodium chloride at an equivalent ionic strength. Conversely, when these organic anions are present in the solution in the acid form, the effect of pH dominates and results in much higher solubility and a calcium/phosphate ratio close to one, indicative of dicalcium phosphate dihydrate as the dominant solid phase.

  3. Study of the tributyl phosphate - 30% dodecane solvent; Etude du solvant phosphate tributylique - 30 % dodecane

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, P. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses. Centre d' Etudes Nucleaires, 92 (France)

    1967-07-01

    This study, originating mainly from a literature survey, gives the principal chemical and physical features of the tributyl-phosphate (TBP) agent diluted at 30 volumes per cent in dodecane. The mixture is a very commonly used extractant in nuclear fuel processing. In this paper, the main following points are reported: -) the components (TBP and diluents) -) the TBP-diluents systems (non-loaded), -) the TBP-diluents-water systems, -) TBP-diluents-water-nitric acid systems, and -) industrial solvents. (author) [French] Cette etude, d'origine bibliographique, regroupe les caracteristiques physico-chimiques essentielles du phosphate tributylique (TBP) dilue a 30% en volume dans du dodecane. Ce melange constitue un agent d'extraction tres utilise dans le traitement des combustibles nucleaires. Les principaux points traites sont les suivants: -) les constituants (TBP et diluants), -) les systemes TBP-diluants non charges, -) les systemes TBP-diluants-eau, -) les systemes TBP-diluants-eau-acide nitrique, et -) les solvants industriels. (auteur)

  4. Evaluation of Manganese Phosphate Coatings.

    Science.gov (United States)

    1984-02-01

    D-AiD9 434 EVALUATION OF MANGANESE PHOSPHATE COTINGS(I) ARMY v/1 ARMAMENT RESEARCH R D DEVELO MENT CENTER IdATERYL lET NY I LARGE CALIBER WEAPON...5Y IIARS 163 TECHNICAL REPORT ARLCB-TR- 64003 EVALUATION OF MANGANESE PHOSPHATE COATINGS R. A. FARRARA FEBRUARY 1984 N US ARMY ARMAMENT RESEARCH AND...84003 _____________ 4. TTLE and -bitle)5. TYPE OF REPORT & PERIOD COVERED EVALUATION OF MANGANESE PHOSPHATE COATINGS Final 6. PERFORMING ORG. REPORT

  5. Corrosion Protection of Steel and Bond Durability at Polyphenylene Sulfide-to-Anhydrous Zinc Phosphate Interfaces

    Science.gov (United States)

    1992-01-01

    Corrosion Protection of Steel and Bond Durability at Polyphenylene Sulfide-to-Anhydrous Zinc Phosphate Interfaces 12 PERSONAL AUTHOR(S) T. Sugana. and...anhydrous zinc phosphate I Zn -Ph )conversion coatings containing poly (acid) inhvdride as an inter- facial tailoring material. The factors contributing to...Sulfide-to-Anhydrous Zinc Phosphate Interfaces T. SUGAMA* and N. R. CARCIELLO Energy Efficiency and Conservation Division, Department of Applied Science

  6. Laser Sintered Calcium Phosphate Bone

    National Research Council Canada - National Science Library

    Vail, Neil

    1999-01-01

    ...) technology selective laser sintering (SLS). BME has successfully implemented a pilot facility to fabricate calcium phosphate implants using anatomical data coupled with the selective laser sintering process...

  7. Behaviour of the pH adjustment, Ion exchange and concentrate precipitation stages in the acid leaching of uranium phosphate ores; Tratamiento de disoluciones de lixiviacion de minerales de uranio en presencia de fosfatos. Comportamiento en las etapas de ajuste de PH, cambio de ion y precipitacion de concentrados

    Energy Technology Data Exchange (ETDEWEB)

    Estrada Aguilar, J.; Uriarte Hueda, A.

    1962-07-01

    The uranium recovery from acid leach solutions of uranium-phosphate ores has been studied. Relations have been found between the solution characteristics and the results obtained at different stages of the process. The following data can thus be predicted: solids to remove and uranium recovery in the pH adjustment stage, uranium capacity of the resin, more suitable eluating agent, elution velocity and uranium concentration in the eluate in the ion exchange stage, and composition of the concentrate produced by direct precipitation of the eluate in the concentrate precipitation stage. (Author) 8 refs.

  8. Structure of escherichia coli ribose-5-phosphate isomerase : a ubiquitous enzyme of the pentose phosphate pathway and the Calvin cycle.

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, R.; Andersson, C. E.; Savchenko, A.; Skarina, T.; Evdokimova, E.; Beasley, S.; Arrowsmith, C. H.; Edwards, A.; Joachimiak, A.; Mowbray, S. L.; Biosciences Division; Uppsala Univ.; Univ. Health Network; Univ. of Toronto; Swedish Univ. of Agricultural Sciences

    2003-01-01

    Ribose-5-phosphate isomerase A (RpiA; EC 5.3.1.6) interconverts ribose-5-phosphate and ribulose-5-phosphate. This enzyme plays essential roles in carbohydrate anabolism and catabolism; it is ubiquitous and highly conserved. The structure of RpiA from Escherichia coli was solved by multiwavelength anomalous diffraction (MAD) phasing, and refined to 1.5 Angstroms resolution (R factor 22.4%, R{sub free} 23.7%). RpiA exhibits an {alpha}/{beta}/({alpha}/{beta})/{beta}/{alpha} fold, some portions of which are similar to proteins of the alcohol dehydrogenase family. The two subunits of the dimer in the asymmetric unit have different conformations, representing the opening/closing of a cleft. Active site residues were identified in the cleft using sequence conservation, as well as the structure of a complex with the inhibitor arabinose-5-phosphate at 1.25 A resolution. A mechanism for acid-base catalysis is proposed.

  9. Origin of Life and the Phosphate Transfer Catalyst

    Science.gov (United States)

    Piast, Radosław W.; Wieczorek, Rafał M.

    2017-03-01

    In this paper, we revisit several issues relevant to origin-of-life research and propose a Phosphate Transfer Catalyst hypothesis that furthers our understanding of some of the key events in prebiotic chemical evolution. In the Phosphate Transfer Catalyst hypothesis, we assume the existence of hypothetical metallopeptides with phosphate transfer activity that use abundant polyphosphates as both substrates and energy sources. Nonspecific catalysis by this phosphate transfer catalyst would provide a variety of different products such as phosphoryl amino acids, nucleosides, polyphosphate nucleotides, nucleic acids, and aminoacylated nucleic acids. Moreover, being an autocatalytic set and metabolic driver at the same time, it could possibly replicate itself and produce a collective system of two polymerases; a nucleic acid able to catalyze peptide bond formation and a peptide able to polymerize nucleic acids. The genetic code starts at first as a system that reduces the energy barrier by bringing substrates (2'/3' aminoacyl-nucleotides) together, an ancestral form of the catalysis performed by modern ribosomes.

  10. The glucose-6-phosphate dehydrogenase encoding genes from Aspergillus niger and Aspergillus nidulans

    NARCIS (Netherlands)

    Broek, van den P.

    1997-01-01


    Glucose-6-phosphate (G6P) is a central metabolite, that can either be metabolised via the glycolytic and tricarboxylic acid cycle to generate ATP, or converted into storage molecules or can be directed to the pentose phosphate pathway to yield NADPH and various pentoses. This thesis

  11. 21 CFR 582.4521 - Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat...

    Science.gov (United States)

    2010-04-01

    ... diglycerides of edible fats or oils, or edible fat-forming fatty acids. 582.4521 Section 582.4521 Food and... Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Monosodium phosphate derivatives of mono- and diglycerides of edible fats or...

  12. Templated, layered manganese phosphate

    Science.gov (United States)

    Thoma, Steven G.; Bonhomme, Francois R.

    2004-08-17

    A new crystalline maganese phosphate composition having an empirical formula: O). The compound was determined to crystallize in the trigonal space group P-3c1 with a=8.8706(4) .ANG., c=26.1580(2) .ANG., and V (volume)=1783 .ANG..sup.3. The structure consists of sheets of corner sharing Mn(II)O.sub.4 and PO.sub.4 tetrahedra with layers of (H.sub.3 NCH.sub.2 CH.sub.2).sub.3 N and water molecules in-between. The pronated (H.sub.3 NCH.sub.2 CH.sub.2).sub.3 N molecules provide charge balancing for the inorganic sheets. A network of hydrogen bonds between water molecules and the inorganic sheets holds the structure together.

  13. Phosphate kinetic models in hemodialysis

    DEFF Research Database (Denmark)

    Laursen, Sisse Heiden; Vestergaard, Peter; Hejlesen, Ole K.

    2018-01-01

    BACKGROUND: Understanding phosphate kinetics in dialysis patients is important for the prevention of hyperphosphatemia and related complications. One approach to gain new insights into phosphate behavior is physiologic modeling. Various models that describe and quantify intra- and/or interdialytic...... phosphate kinetics have been proposed, but there is a dearth of comprehensive comparisons of the available models. The objective of this analysis was to provide a systematic review of existing published models of phosphate metabolism in the setting of maintenance hemodialysis therapy. STUDY DESIGN......: Systematic review. SETTING & POPULATION: Hemodialysis patients. SELECTION CRITERIA FOR STUDIES: Studies published in peer-reviewed journals in English about phosphate kinetic modeling in the setting of hemodialysis therapy. PREDICTOR: Modeling equations from specific reviewed studies. OUTCOMES: Changes...

  14. Kinetic and Equilibrium Constants of Phytic Acid, Ferric and Ferrous Phytate Derived From Nuclear Magnetic Resonance Spectroscopy

    Science.gov (United States)

    Inositol phosphates are metabolically derived organic phosphates that increasingly appear to be an important sink and source of phosphate in the environment. Inositol hexakis dihydrogen phosphate or phytic acid is the most common inositol phosphate in the environment. Iron is abundant in many terr...

  15. Evaluation of dissolution of nonconventional phosphate fertilizers in ...

    African Journals Online (AJOL)

    Three phosphate fertilizer materials: finely ground (0.150-mm screen) Dorowa PR (DPR); DPR partially acidulated with 50 % of the sulfuric acid required for complete acidulation (PADPR); and a compacted mixture of DPR + triple superphosphate (TSP) + urea + potassium chloride (DTUK) with half of the P from DPR and ...

  16. Characterization of Phosphate Solubilizing Faba Bean ( Vicia faba L ...

    African Journals Online (AJOL)

    Some species of rhizobial bacteria nodulating faba bean are characterized by phosphate solubilization. In order to study their in vitro and symbiotic characteristics, twelve rhizobial isolates nodulating faba bean were collected from acidic soil of Wollega, Ethiopia. Solubilization index of the isolates ranges from 1.25 to 2.10.

  17. Phosphate solubilization as a microbial strategy for promoting plant growth

    Directory of Open Access Journals (Sweden)

    Mayra Eleonora Beltrán Pineda

    2014-01-01

    Full Text Available Because of the constant application of chemical inputs in Agroecosystem, the cost of crop production and environmental quality of soil and water have been affected. Microorganisms carry out most biogeochemical cycles; therefore, their role is essential for agro ecosystem balance. One such functional group is the phosphate solubilizing microorganisms, which are recognized plant growth promoters. These microbial populations perform an important activity, since in many soils there are large reserves of insoluble phosphorus, as a result of fixing much of the phosphorus fertilizer applied, which cannot be assimilated by the plant. The phosphate solubilizing microorganisms use different solubilization mechanisms such as the production of organic acids, which solubilize theses insoluble phosphates in the rhizosphere region. Soluble phosphates are absorbed by the plant, which enhances their growth and productivity. By using these phosphate reserves in soils, application of chemical fertilizers is decreased, on the one hand, can again be fixed by ions Ca, Al or Fe making them insoluble and, by the other hand, increase the costs of crop production. Microbial populations have been widely studied in different types of ecosystems, both natural and Agroecosystem. Thanks to its effectiveness, in laboratory and field studies, the phosphate solubilizing phenotype is of great interest to microbial ecologists who have begun to establish the molecular basis of the traitr.

  18. Mise en valeur des minerais de phosphate par flottation | Boukraa ...

    African Journals Online (AJOL)

    Les acides gras fractions C10-C16 jouent le rôle de collecteurs anioniques dans la flottation des carbonates alors que le triazine est utilisé comme collecteur cationique pour flotter le quartz. Le concentré de phosphate obtenu pourra être utilisé pour la fabrication de l'acide phosphorique et de superphosphate en qualité ...

  19. Triphenyl phosphate allergy from spectacle frames

    DEFF Research Database (Denmark)

    Carlsen, Lars; Andersen, Klaus E.; Egsgaard, Helge

    1986-01-01

    A case of triphenyl phosphate allergy from spectacle frames is reported. Patch tests with analytical grade triphenyl phosphate, tri-m-cresyl phosphate, and tri-p-cresyl phosphate in the concentrations 5%, 0.5% and 0.05% pet. showed positive reactions to 0.05% triphenyl phosphate and 0.5% tri......-m-cresyl phosphate, but no reaction to tri-p-cresyl phosphate. Gas chromatography of the tricresyl phosphate 5% pet. patch test material supplied from Trolab showed that it contained a mixture of a wide range of triaryl phosphates, including 0.08% triphenyl phosphate which is above the threshold for detecting...... triphenyl phosphate allergy in our patient....

  20. Alpha-tricalcium phosphate hydrolysis to octacalcium phosphate: effect of sodium polyacrylate.

    Science.gov (United States)

    Bigi, A; Boanini, E; Botter, R; Panzavolta, S; Rubini, K

    2002-04-01

    Alpha-Tricalcium phosphate (alpha-TCP) hydrolysis into octacalcium phosphate (OCP) has been investigated in phosphoric acid solution at different concentrations of sodium polyacrylate (NaPA). The hydrolysis process has been followed by powder X-ray diffraction, infrared absorption and scanning electron microscopy analyses. In the absence of the polyelectrolyte, alpha-TCP undergoes a complete transformation into OCP in 24 h. The presence of polyacrylate in solution inhibits the hydrolysis so that a NaPA concentration of 0.5 microm is sufficient to lengthen the time required to complete the hydrolysis to 4 days. The variation of Ca2+ concentration in the soaking solution suggests that the transformation occurs through alpha-TCP dissolution followed by OCP precipitation. The delayed OCP nucleation and growth in the presence of polyacrylate implies a preferential adsorption of the polyelectrolyte on the growing OCP crystals, which induces an anisotropic reduction of the coherence lengths of the perfect crystalline domains.

  1. High inorganic phosphate causes DNMT1 phosphorylation and subsequent fibrotic fibroblast activation

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Xiaoying [Department of Nephrology and Rheumatology, Göttingen University Medical Center, Georg August University, Göttingen (Germany); Department of Cardiology and Pneumology, Göttingen University Medical Center, Georg August University, Göttingen (Germany); Xu, Xingbo [Department of Cardiology and Pneumology, Göttingen University Medical Center, Georg August University, Göttingen (Germany); Zeisberg, Elisabeth M. [Department of Cardiology and Pneumology, Göttingen University Medical Center, Georg August University, Göttingen (Germany); German Center for Cardiovascular Research (DZHK), Göttingen (Germany); Zeisberg, Michael, E-mail: mzeisberg@med.uni-goettingen.de [Department of Nephrology and Rheumatology, Göttingen University Medical Center, Georg August University, Göttingen (Germany); German Center for Cardiovascular Research (DZHK), Göttingen (Germany)

    2016-04-08

    Phosphate is an essential constituent of critical cellular functions including energy metabolism, nucleic acid synthesis and phosphorylation-dependent cell signaling. Increased plasma phosphate levels are an independent risk factor for lowered life-expectancy as well as for heart and kidney failure. Nevertheless, direct cellular effects of elevated phosphate concentrations within the microenvironment are poorly understood and have been largely neglected in favor of phosphor-regulatory hormones. Because interstitial fibrosis is the common determinant of chronic progressive kidney disease, and because fibroblasts are major mediators of fibrogenesis, we here explored the effect of high extracellular phosphate levels on renal fibroblasts. We demonstrate that high inorganic phosphate directly induces fibrotic fibroblast activation associated with increased proliferative activity, increased expression of α-smooth muscle actin and increased synthesis of type I collagen. We further demonstrate that such fibroblast activation is dependent on phosphate influx, aberrant phosphorylation of DNA methyltransferase DNMT1 and aberrant CpG island promoter methylation. In summary, our studies demonstrate that elevated phosphate concentrations induce pro-fibrotic fibroblast activation independent of phospho-regulatory hormones. - Highlights: • We exposed human kidney fibroblasts to media containing 1 mM or 3 mM phosphate. • Increased phosphate influx causes phosphorylation of DNA methyltransferase Dnmt1. • Phosphorylated Dnmt1 causes promoter methylation and transcriptional silencing of RASAL1. • Depletion of RASAL1 causes increased intrinsic Ras-GTP activity and fibroblast activation. • Inorganic phosphate causes fibroblast activation independent of phospho-regulatory hormones.

  2. Removal of Phosphate Using Red Mud: An Environmentally Hazardous Waste By-Product of Alumina Industry

    Directory of Open Access Journals (Sweden)

    Shivkumar S. Prajapati

    2016-01-01

    Full Text Available The industrial waste, bauxite residue generated in the Bayer chemical process of alumina production, commonly known as red mud (RM has been used as the adsorbent for selective removal of phosphate in aqueous solutions. RM collected from the storage area of alumina industry was characterized by chemical analysis and physical methods such as BET surface area, Scanning Electron Microscopy (SEM, particle size analysis, and X-ray diffraction (XRD methods. Among the various red mud samples (0.2–200 μ studied, the samples treated with 1 M HCl for 2 h were found better for the selective adsorption of phosphate in comparison with untreated and heat treated RM samples. The presence of phosphate in the aqueous samples collected after adsorption studies with red mud was determined by standard spectrophotometric procedure using ammonium molybdate and ascorbic acid in nitrate medium at λmax 880 nm. The studies reported significant adsorption of phosphate on acid treated red mud in comparison with adsorption of phosphate on untreated and heat treated red mud, respectively. The adsorption of phosphate on raw red mud and activated red mud was further investigated with respect to stirring time, pH of the solution, dose of adsorbent, and varying phosphate concentration. Acid treated RM is observed as an efficient and cost-effective adsorbent for selective removal of phosphate in aqueous solutions.

  3. Method and apparatus for ion sequestration and a nanostructured metal phosphate

    Science.gov (United States)

    Mattigod, Shas V [Richland, WA; Fryxell, Glen E [Kennewic, WA; Li, Xiaohong [Richland, WA; Parker, Kent E [Kennewick, WA; Wellman, Dawn M [West Richland, WA

    2010-04-06

    A nanostructured substance, a process for sequestration of ionic waste, and an ion-sequestration apparatus are disclosed in the specification. The nanostructured substance can comprise a Lewis acid transition metal bound to a phosphate, wherein the phosphate comprises a primary structural component of the substance and the Lewis acid transition metal is a reducing agent. The nanostructured substance has a Brunner-Emmet-Teller (BET) surface area greater than or equal to approximately 100 m.sup.2/g, and a distribution coefficient for an analyte, K.sub.d, greater than or equal to approximately 5000 ml/g. The process can comprise contacting a fluid and a nanostructured metal phosphate. The apparatus can comprise a vessel and a nanostructured metal phosphate. The vessel defines a volume wherein a fluid contacts the nanostructured metal phosphate.

  4. Calcium phosphates for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Canillas, M.; Pena, P.; Aza, A.H. de; Rodriguez, M.A.

    2017-07-01

    The history of calcium phosphates in the medicine field starts in 1769 when the first evidence of its existence in the bone tissue is discovered. Since then, the interest for calcium phosphates has increased among the scientific community. Their study has been developed in parallel with new advances in materials sciences, medicine or tissue engineering areas. Bone tissue engineering is the field where calcium phosphates have had a great importance. While the first bioceramics are selected according to bioinert, biocompatibility and mechanical properties with the aim to replace bone tissue damaged, calcium phosphates open the way to the bone tissue regeneration challenge. Nowadays, they are present in the majority of commercial products directed to repair or regenerate damaged bone tissue. Finally, in the last few decades, they have been suggested and studied as drug delivering devices and as vehicles of DNA and RNA for the future generation therapies. (Author)

  5. 21 CFR 573.320 - Diammonium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Diammonium phosphate. 573.320 Section 573.320 Food... Additive Listing § 573.320 Diammonium phosphate. The food additive diammonium phosphate may be safely used... crude protein from diammonium phosphate, adequate directions for use and a prominent statement, “Warning...

  6. A colorimetric determination of inositol monophosphates as an assay for d-glucose 6-phosphate–1l-myoinositol 1-phosphate cyclase

    Science.gov (United States)

    Barnett, J. E. G.; Brice, R. E.; Corina, D. L.

    1970-01-01

    A rapid and convenient chemical assay for the enzyme d-glucose 6-phosphate–1l-myoinositol 1-phosphate cyclase is described. The 1l-myoinositol 1-phosphate formed enzymically was oxidized with periodic acid liberating inorganic phosphate, which was assayed. myoInositol 2-phosphate can be assayed in the same way. Glucose 6-phosphate and other primary phosphate esters gave only very small quantities of inorganic phosphate under the conditions described. The Km of the enzyme for d-glucose 6-phosphate, 7.5±2.5×10−4m, was identical with that measured by the radiochemical method. 2-Deoxy-d-glucose 6-phosphate was a powerful competitive inhibitor, Ki 2.0±0.5×10−5m, but was not a substrate for the enzyme. PMID:4321269

  7. [Biodiversity of phosphate-dissolving and plant growth--promoting endophytic bacteria of two crops].

    Science.gov (United States)

    Huang, Jing; Sheng, Xiafang; He, Linyan

    2010-06-01

    We isolated and characterized phosphate-dissolving endophytic bacteria from two commonly cultivated crops. Phosphate-dissolving endophytic bacteria were isolated by plating and screening from interior tissues of rape and maize plants on NBRIP medium with tricalcium phosphate as sole phosphate source. Bacteria were characterized regarding characteristics that may be relevant for a beneficial plant-microbe interaction-indoleacetic acid, siderophore and 1-aminocyclopropane-1-carboxylic acid deaminase production,and further classified by restriction analysis of 16S rDNA. Eleven typical strains were identified by 16S rDNA sequence analysis. Thirty-two phosphate-dissolving endophytic bacteria were isolated from maize and rape plants and classified by restriction analysis of 16S rDNA in 8 different taxonomic groups at the similarity level of 76%. All the isolates could release phosphate from tricalcium phosphate and decrease the pH of the medium. The maximum phosphate content (537.6 mg/L) in the solution was obtained with strain M1L5. Thirteen isolates isolated from rape produced indoleacetic acid and siderophore, 68.4% and 63.2% of the strains isolated from maize produced indoleacetic acid and siderophore,respectively. 63.2% of the strains isolated from maize were able to grow on 1-aminocyclopropane-1-carboxylic acid as the sole nitrogen source. The eleven strains belonged to five different genera including Pantoea, Pseudomonas, Burkholderia, Acinetobacter and Ralstonia. Phosphate-dissolving endophytic bacteria isolated from rape and maize plants have abundant characteristics relative to promoting plant growth and genetic diversity.

  8. Chemical characteristics of aerosol mists in phosphate fertilizer manufacturing facilities.

    Science.gov (United States)

    Hsu, Yu-Mei; Wu, Chang-Yu; Lundgren, Dale A; Nall, J Wesley; Birky, Brian K

    2007-01-01

    Of the carcinogens listed by the National Toxicology Program (NTP), strong inorganic mists containing sulfuric acid were identified as a known human carcinogen. In this study, aerosol sampling was conducted at 24 locations in eight Florida phosphoric acid and concentrated fertilizer manufacturing plants and two locations as background in Winter Haven and Gainesville, Florida, using dichotomous samplers. The locations were selected where sulfuric acid mist may potentially exist, including sulfuric acid pump tank areas, belt or rotating table phosphoric acid filter floors, sulfuric acid truck loading/unloading stations, phosphoric acid production reactors (attack tanks), and a concentrated fertilizer granulator during scrubbing with a weak sulfuric acid mixture. An ion chromatography system was used to analyze sulfate and other water soluble ion species. In general, sulfate, fluoride, ammonium, and phosphate were the major species in the fertilizer facilities. For the rotating table/belt phosphoric acid filter floor, phosphate and fluoride were the dominant species for PM10, and the maximum concentrations were 170 and 106 microg/m3, respectively. For the attack tank, fluoride was the dominant species for PM10, and the maximum concentration was 462 microg/m3. At the sulfuric acid pump tank, sulfate was the dominant species, and the maximum PM10 sulfate concentration was 181 microg/m3. The concentration of PM10 sulfate including ammonium sulfate, calcium sulfate, and sulfuric acid were lower than 0.2 mg/m3 at all locations. The aerosols at the filter floor and the attack tank were acidic. The coarse mode aerosol at the sulfuric acid pump tank (an outdoor location) was acidic, whereas the fine mode aerosol was neutral to basic.

  9. Isolation of phosphatase-producing phosphate solubilizing bacteria from Loriya hot spring: Investigation of phosphate solubilizing in the presence of different parameters

    Directory of Open Access Journals (Sweden)

    Maryam Parhamfar

    2014-04-01

    Full Text Available Introduction: Biofertilizers are the microorganisms that can convert useless nutrient to usable compounds. Unlike fertilizer, cost of biofertilizer production is low and doesn’t produce ecosystem pollution. Phosphate fertilizers can be replaced by phosphate biofertilizer to produce improvement. So, it is necessary to screen the climate-compatible phosphate solubilizing bacteria. Materials and methods: In this project samples were picked up from Loriya hot spring, which are located in Jiroft. Samples were incubated in PKV medium for 3 days. Screening of phosphate solubilizing bacteria was performed on the specific media, based on clear area diameter. The best bacterium was identified based on 16s rDNA gene. Phosphate solubilizing activity of this strain was considered in different carbon, nitrogen, phosphate and pH sources. Results: Sequence alignment and phylogenetic tree results show that B. sp. LOR033 is closely related to Bacillus licheniformis, with 97% homology. In addition, results show that maximum enzyme production was performed after 2 days that incubation pH was decreased simultaneously when the time was increased. Carbon sources investigation show that glucose is the most appropriate in enzyme production and phosphate releasing. Furthermore, results show that the optimum initial pH for phytase production was pH5.0. Different phosphate sources show that tricalcium phosphate has the suitable effect on enzyme activity in three days of incubation. Discussion and conclusion: Phosphatase enzyme production capacity, growth in acidic pH and phosphate solubilizing potential in different salt and phosphate sources show that this strain has considerable importance as biofertilizers.

  10. Uranium phosphate biomineralization by fungi.

    Science.gov (United States)

    Liang, Xinjin; Hillier, Stephen; Pendlowski, Helen; Gray, Nia; Ceci, Andrea; Gadd, Geoffrey Michael

    2015-06-01

    Geoactive soil fungi were investigated for phosphatase-mediated uranium precipitation during growth on an organic phosphorus source. Aspergillus niger and Paecilomyces javanicus were grown on modified Czapek-Dox medium amended with glycerol 2-phosphate (G2P) as sole P source and uranium nitrate. Both organisms showed reduced growth on uranium-containing media but were able to extensively precipitate uranium and phosphorus-containing minerals on hyphal surfaces, and these were identified by X-ray powder diffraction as uranyl phosphate species, including potassium uranyl phosphate hydrate (KPUO6 .3H2 O), meta-ankoleite [(K1.7 Ba0.2 )(UO2 )2 (PO4 )2 .6H2 O], uranyl phosphate hydrate [(UO2 )3 (PO4 )2 .4H2 O], meta-ankoleite (K(UO2 )(PO4 ).3H2 O), uramphite (NH4 UO2 PO4 .3H2 O) and chernikovite [(H3 O)2 (UO2 )2 (PO4 )2 .6H2 O]. Some minerals with a morphology similar to bacterial hydrogen uranyl phosphate were detected on A. niger biomass. Geochemical modelling confirmed the complexity of uranium speciation, and the presence of meta-ankoleite, uramphite and uranyl phosphate hydrate between pH 3 and 8 closely matched the experimental data, with potassium as the dominant cation. We have therefore demonstrated that fungi can precipitate U-containing phosphate biominerals when grown with an organic source of P, with the hyphal matrix serving to localize the resultant uranium minerals. The findings throw further light on potential fungal roles in U and P biogeochemistry as well as the application of these mechanisms for element recovery or bioremediation. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  11. Intracellular alkalinization by phosphate uptake via type III sodium-phosphate cotransporter participates in high-phosphate-induced mitochondrial oxidative stress and defective insulin secretion.

    Science.gov (United States)

    Nguyen, Tuyet Thi; Quan, Xianglan; Xu, Shanhua; Das, Ranjan; Cha, Seung-Kuy; Kong, In Deok; Shong, Minho; Wollheim, Claes B; Park, Kyu-Sang

    2016-12-01

    Elevated plasma levels of inorganic phosphate (Pi) are harmful, causing, among other complications, vascular calcification and defective insulin secretion. The underlying molecular mechanisms of these complications remain poorly understood. We demonstrated the role of Pi transport across the plasmalemma on Pi toxicity in INS-1E rat clonal β cells and rat pancreatic islet cells. Type III sodium-phosphate cotransporters (NaPis) are the predominant Pi transporters expressed in insulin-secreting cells. Transcript and protein levels of sodium-dependent phosphate transporter 1 and 2 (PiT-1 and -2), isotypes of type III NaPi, were up-regulated by high-Pi incubation. In patch-clamp experiments, extracellular Pi elicited a Na(+)-dependent, inwardly rectifying current, which was markedly reduced under acidic extracellular conditions. Cellular uptake of Pi elicited cytosolic alkalinization; intriguingly, this pH change facilitated Pi transport into the mitochondrial matrix. Increased mitochondrial Pi uptake accelerated superoxide generation, mitochondrial permeability transition (mPT), and endoplasmic reticulum stress-mediated translational attenuation, leading to reduced insulin content and impaired glucose-stimulated insulin secretion. Silencing of PiT-1/2 prevented Pi-induced superoxide generation and mPT, and restored insulin secretion. We propose that Pi transport across the plasma membrane and consequent cytosolic alkalinization could be a therapeutic target for protection from Pi toxicity in insulin-secreting cells, as well as in other cell types.-Nguyen, T. T., Quan, X., Xu, S., Das, R., Cha, S.-K., Kong, I. D., Shong, M., Wollheim, C. B., Park, K.-S. Intracellular alkalinization by phosphate uptake via type III sodium-phosphate cotransporter participates in high-phosphate-induced mitochondrial oxidative stress and defective insulin secretion. © FASEB.

  12. Phosphate toxicity: new insights into an old problem.

    Science.gov (United States)

    Razzaque, M Shawkat

    2011-02-01

    Phosphorus is an essential nutrient required for critical biological reactions that maintain the normal homoeostatic control of the cell. This element is an important component of different cellular structures, including nucleic acids and cell membranes. Adequate phosphorus balance is vital for maintaining basic cellular functions, ranging from energy metabolism to cell signalling. In addition, many intracellular pathways utilize phosphate ions for important cellular reactions; therefore, homoeostatic control of phosphate is one of the most delicate biological regulations. Impaired phosphorus balance can affect the functionality of almost every human system, including musculoskeletal and cardiovascular systems, ultimately leading to an increase in morbidity and mortality of the affected patients. Human and experimental studies have found that delicate balance among circulating factors, like vitamin D, PTH (parathyroid hormone) and FGF23 (fibroblast growth factor 23), are essential for regulation of physiological phosphate balance. Dysregulation of these factors, either alone or in combination, can induce phosphorus imbalance. Recent studies have shown that suppression of the FGF23-klotho system can lead to hyperphosphataemia with extensive tissue damage caused by phosphate toxicity. The cause and consequences of phosphate toxicity will be briefly summarized in the present review.

  13. Gene Cloning of Iranian Leishmania major Mannose-1-Phosphate Guanyltransferase

    Directory of Open Access Journals (Sweden)

    R Salehi

    2009-07-01

    Full Text Available "nBackground: Leishmania is an obligatory intracellular protozoan parasite, which infects human be­ings when infected sand fly vector takes a blood meal.  Most efforts are towards designing an effective vaccine to prevent leishmaniasis. In this way, development of candidate antigen for vaccine has spe­cial im­portant. In this study, we cloned mannose-1-phosphate guanyltransferase gene of Iranian L .major in pET32a expression vector. "nMethods: Primers based on L. major mannose-1-phosphate guanyltransferase sequence gene was de­signed and synthesized. DNA of Leishmania promastigotes was extracted and PCR reaction was done. PCR product was cloned into pTZ57R and sub cloned into pET32a expression vector. "nResults: Recombinant plasmid containing 1140 bp as L. major mannose-1-phosphate guanyltrans­ferase gene was extracted and confirmed by restriction analysis. PCR product was sequenced and de­posited to GenBank. There were some differences in amino acid sequences between Iranian L. major mannose-1-phosphate guanyltransferase and others previously accepted in GenBank "nConclusion: We amplified and cloned Iranian L. major mannose-1-phosphate guanyltransferase successfully.

  14. Phosphate removal from aqueous solutions using kaolinite obtained from Linthipe, Malawi

    Science.gov (United States)

    Kamiyango, M. W.; Masamba, W. R. L.; Sajidu, S. M. I.; Fabiano, E.

    Earlier work on stream water and effluent from wastewater treatment plants in Blantyre, Malawi, has revealed high phosphate levels ranging from 0.63 to 5.50 mg/L. These phosphate levels would stimulate excessive growth of plants and toxic cyanobacteria in stagnant receiving water bodies hence posing a threat to aquatic life and water quality. Phosphate removal by kaolinite obtained from Linthipe, Malawi, was investigated as a function of pH, contact time, clay dosage, competing ions and initial phosphate concentration by means of jar tests. Phosphate uptake was pH dependent with adsorption mechanisms on kaolinite and iron oxide surfaces dominant generally below pH 7 and precipitation by calcium ions dominant above pH 7. Maximum phosphate removal occurred at high pH values of 11.22 (97.1%) and 10.96 (100%) for raw and treated kaolinite, respectively. Acid treated kaolinite indicated higher phosphate removal efficiency than the raw one at the normal working pH of 9.0 ± 0.2. This was attributed to release of extra calcium ions from CaCO 3 present in the kaolinite samples during acid treatment. At the maximum dosage of 80 g/L, percent phosphate removal was 69.7 ± 0.100% and 98.5 ± 0.0577% for raw and treated kaolinite, respectively. This indicates requirement for high dosages to effect phosphate removal from the aqueous solutions. Studies on the effects of competing ions indicate that phosphate uptake decreased in the presence of CO32-, was little affected by SO42-, and increased in the presence of Ca 2+, and Mg 2+ ions. Furthermore, phosphate uptake approached equilibrium slowly at 20 °C and was faster at 40 °C.

  15. Homo-D-lactic acid fermentation from arabinose by redirection of the phosphoketolase pathway to the pentose phosphate pathway in L-lactate dehydrogenase gene-deficient Lactobacillus plantarum.

    Science.gov (United States)

    Okano, Kenji; Yoshida, Shogo; Tanaka, Tsutomu; Ogino, Chiaki; Fukuda, Hideki; Kondo, Akihiko

    2009-08-01

    Optically pure d-lactic acid fermentation from arabinose was achieved by using the Lactobacillus plantarum NCIMB 8826 strain whose l-lactate dehydrogenase gene was deficient and whose phosphoketolase gene was substituted with a heterologous transketolase gene. After 27 h of fermentation, 38.6 g/liter of d-lactic acid was produced from 50 g/liter of arabinose.

  16. Activation and fluoride-assisted phosphating of aluminum-silicon-coated steel.

    Science.gov (United States)

    Schneider, Paul; Sigel, Reinhard; Lange, Miriam M; Beier, Frank; Renner, Frank U; Erbe, Andreas

    2013-05-22

    Phosphating is a crucial process in the corrosion protection of metals. Here, activation and fluoride-assisted tricationic phosphating is investigated on aluminum-silicon (AS) coated steel surfaces. Dynamic light scattering results from the activation bath show a bimodal size distribution, with hydrodynamic radii of ~400 nm and ~10 μm. For the smaller particle fraction, static light scattering results are consistent with the interpretation of disklike particles as scattering objects. Particles of the larger fraction sediment with time. In the presence of electrolyte, the scattering intensity from the larger particle fraction increases. Coagulation with time is suggested to be related to the decrease in activity of the activation bath. Scanning Auger microscopy (SAM) shows a higher phosphorus concentration after titanium phosphate activation in the Al-rich areas compared to the Si-rich areas of the AS coatings. There is no correlation between the size of the species in the activation bath, and the size of the phosphate-containing regions on the activated surface. Phosphating was performed in the presence of hexafluorosilicic acid, H2SiF6, ammonium hydrogen difluoride, NH4HF2, and both, at an initial pH of 2.5. The absence of crystals after phosphating with H2SiF6 is an indication that SiF6(2-) is the final product of the oxide dissolution in the presence of fluoride. In the presence of NH4HF2, the Si-rich regions of the surface are phosphated before the Si-poor (Al-rich) regions. Hence, the phosphate distribution after activation and after phosphating are opposite. These results show that a high surface concentration of phosphate after activation is not sufficient for a high coverage with phosphate crystals after phosphating.

  17. The chemistry of tributyl phosphate at elevated temperatures in the Plutonium Finishing Plant Process Vessels

    Energy Technology Data Exchange (ETDEWEB)

    Barney, G.S.; Cooper, T.D.

    1994-06-01

    Potentially violent chemical reactions of the tributyl phosphate solvent used by the Plutonium Finishing Plant at the Hanford Site were investigated. There is a small probability that a significant quantity of this solvent could be accidental transferred to heated process vessels and react there with nitric acid or plutonium nitrate also present in the solvent extraction process. The results of laboratory studies of the reactions show that exothermic oxidation of tributyl phosphate by either nitric acid or actinide nitrates is slow at temperatures expected in the heated vessels. Less than four percent of the tributyl phosphate will be oxidized in these vented vessels at temperatures between 125{degrees}C and 250{degrees}C because the oxidant will be lost from the vessels by vaporization or decomposition before the tributyl phosphate can be extensively oxidized. The net amounts of heat generated by oxidation with concentrated nitric acid and with thorium nitrate (a stand-in for plutonium nitrate) were determined to be about -150 and -220 joules per gram of tributyl phosphate initially present, respectively. This is not enough heat to cause violent reactions in the vessels. Pyrolysis of the tributyl phosphate occurred in these mixtures at temperatures of 110{degrees}C to 270{degrees}C and produced mainly 1-butene gas, water, and pyrophosphoric acid. Butene gas generation is slow at expected process vessel temperatures, but the rate is faster at higher temperatures. At 252{degrees}C the rate of butene gas generated was 0.33 g butene/min/g of tributyl phosphate present. The measured heat absorbed by the pyrolysis reaction was 228 J/g of tributyl phosphate initially present (or 14.5 kcal/mole of tributyl phosphate). Release of flammable butene gas into process areas where it could ignite appears to be the most serious safety consideration for the Plutonium Finishing Plant.

  18. Phosphate-solubilizing bacteria associated with runner bean rhizosphere

    Directory of Open Access Journals (Sweden)

    Mihalache Gabriela

    2015-01-01

    Full Text Available Soil microorganisms, especially rhizobacteria, play a key role in soil phosphorus (P dynamics and the subsequent availability of phosphate to plants. Utilization of phosphate-solubilizing bacteria as biofertilizers instead of synthetic chemicals is known to improve plant growth through the supply of plant nutrients, and may help to sustain environmental health and soil productivity. The main purpose of this study was to identify new phosphate-solubilizing bacteria isolated from runner bean rhizosphere. Ten out of 25 isolated bacterial strains solubilized Ca3(PO42 in qualitative and quantitative P-solubilization. The strain that exhibited the highest potential to solubilize Ca3(PO42, was selected for further determination of the mechanisms involved in the process. The medium pH was measured, organic acids released in the culture medium were identified by HPLC analysis, and the acid and alkaline phosphatase activities were determined. Our results showed that strain R7 solubilized phosphorous through the production of various organic acids such as lactic, isocitric, tartaric and pyruvic acids, and that it can be used as a potential biofertilizer.

  19. Final Report: Dominant Mechanisms of Uranium-Phosphate Reactions in Subsurface Sediments

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, Jeffrey G. [Washington Univ., St. Louis, MO (United States); Giammar, Daniel E. [Washington Univ., St. Louis, MO (United States); Wang, Zheming [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-03-08

    Phosphate addition is an in situ remediation approach that may enhance the sequestration of uranium without requiring sustained reducing conditions. However, the geochemical factors that determine the dominant immobilization mechanisms upon phosphate addition are insufficiently understood to design efficient remediation strategies or accurately predict U(VI) transport. The overall objective of our project is to determine the dominant mechanisms of U(VI)-phosphate reactions in subsurface environments. Our research approach seeks to determine the U(VI)-phosphate solid that form in the presence of different groundwater cations, characterize the effects of phosphate on U(VI) adsorption and precipitation on smectite and iron oxide minerals, examples of two major reactive mineral phases in contaminated sediments, and investigate how phosphate affects U(VI) speciation and fate during water flow through sediments from contaminated sites. The research activities conducted for this project have generated a series of major findings. U(VI) phosphate solids from the autunite mineral family are the sole phases to form during precipitation, with uranyl orthophosphate not occurring despite its predicted greater stability. Calcium phosphates may take up substantial quantities of U(VI) through three different removal processes (adsorption, coprecipitation, and precipitation) but the dominance of each process varies with the pathway of reaction. Phosphate co-adsorbs with U(VI) onto smectite mineral surfaces, forming a mixed uranium-phosphate surface complex over a wide range of conditions. However, this molecular-scale association of uranium and phosphate has not effect on the overall extent of uptake. In contrast, phosphate enhanced U(VI) adsorption to iron oxide minerals at acidic pH conditions but suppresses such adsorption at neutral and alkaline pH, despite forming mixed uranium-phosphate surface complexes during adsorption. Nucleation barriers exist that inhibit U(VI) phosphate

  20. Biotechnological production of citric acid

    National Research Council Canada - National Science Library

    Max, Belén; Salgado, José Manuel; Rodríguez, Noelia; Cortés, Sandra; Converti, Attilio; Domínguez, José Manuel

    2010-01-01

    .... Several factors affecting citric acid fermentation are discussed, including carbon source, nitrogen and phosphate limitations, pH of culture medium, aeration, trace elements and morphology of the fungus...

  1. Interactions of phosphate solubilising microorganisms with natural rare-earth phosphate minerals: a study utilizing Western Australian monazite.

    Science.gov (United States)

    Corbett, Melissa K; Eksteen, Jacques J; Niu, Xi-Zhi; Croue, Jean-Philippe; Watkin, Elizabeth L J

    2017-06-01

    Many microbial species are capable of solubilising insoluble forms of phosphate and are used in agriculture to improve plant growth. In this study, we apply the use of known phosphate solubilising microbes (PSM) to the release of rare-earth elements (REE) from the rare-earth phosphate mineral, monazite. Two sources of monazite were used, a weathered monazite and mineral sand monazite, both from Western Australia. When incubated with PSM, the REE were preferentially released into the leachate. Penicillum sp. released a total concentration of 12.32 mg L-1 rare-earth elements (Ce, La, Nd, and Pr) from the weathered monazite after 192 h with little release of thorium and iron into solution. However, cultivation on the mineral sands monazite resulted in the preferential release of Fe and Th. Analysis of the leachate detected the production of numerous low-molecular weight organic acids. Gluconic acid was produced by all microorganisms; however, other organic acids produced differed between microbes and the monazite source provided. Abiotic leaching with equivalent combinations of organic acids resulted in the lower release of REE implying that other microbial processes are playing a role in solubilisation of the monazite ore. This study demonstrates that microbial solubilisation of monazite is promising; however, the extent of the reaction is highly dependent on the monazite matrix structure and elemental composition.

  2. Improved production of homo-D-lactic acid via xylose fermentation by introduction of xylose assimilation genes and redirection of the phosphoketolase pathway to the pentose phosphate pathway in L-Lactate dehydrogenase gene-deficient Lactobacillus plantarum.

    Science.gov (United States)

    Okano, Kenji; Yoshida, Shogo; Yamada, Ryosuke; Tanaka, Tsutomu; Ogino, Chiaki; Fukuda, Hideki; Kondo, Akihiko

    2009-12-01

    The production of optically pure d-lactic acid via xylose fermentation was achieved by using a Lactobacillus plantarum NCIMB 8826 strain whose l-lactate dehydrogenase gene was deficient and whose phosphoketolase genes were replaced with a heterologous transketolase gene. After 60 h of fermentation, 41.2 g/liter of d-lactic acid was produced from 50 g/liter of xylose.

  3. Thermal Decomposition of Nitrated Tributyl Phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Paddleford, D.F. [Westinghouse Savannah River Company, Aiken, SC (United States); Hou, Y.; Barefield, E.K.; Tedder, D.W.; Abdel-Khalik, S.I. [Georgia Institute of Technology, GA (United States)

    1995-01-01

    Contact between tributyl phosphate and aqueous solutions of nitric acid and/or heavy metal nitrate salts at elevated temperatures can lead to exothermic reactions of explosive violence. Even though such operations have been routinely performed safely for decades as an intrinsic part of the Purex separation processes, several so-called ``red oil`` explosions are known to have occurred in the United States, Canada, and the former Soviet Union. The most recent red oil explosion occurred at the Tomsk-7 separations facility in Siberia, in April 1993. That explosion destroyed part of the unreinforced masonry walls of the canyon-type building in which the process was housed, and allowed the release of a significant quantity of radioactive material.

  4. Methylerythritol Phosphate Pathway of Isoprenoid Biosynthesis

    Science.gov (United States)

    Zhao, Lishan; Chang, Wei-chen; Xiao, Youli; Liu, Hung-wen; Liu, Pinghua

    2016-01-01

    Isoprenoids are a class of natural products with more than 50,000 members. All isoprenoids are constructed from two precursors, isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP). Two of the most important discoveries in isoprenoid biosynthetic studies in recent years are the elucidation of a second isoprenoid biosynthetic pathway (the methylerythritol phosphate (MEP) pathway) and a modified mevalonate (MVA) pathway. In this review, mechanistic insights on the MEP pathway enzymes are summarized. Since many isoprenoids have important biological activities, the need to produce them in sufficient quantities for downstream research efforts or commercial application is apparent. Recent advances in both the MVA and MEP pathway-based synthetic biology efforts are also illustrated by reviewing the landmark work of artemisinic acid and taxadien-5α-ol production through microbial fermentations. PMID:23746261

  5. Potency of Agroindustrial Wastewaters to Increase the Dissolution of Phosphate Rock Fertilizers

    Directory of Open Access Journals (Sweden)

    Ainin Niswati

    2014-06-01

    Full Text Available The used of agroindustrial wastewaters are not maximum yet in Lampung Province, althought it can be used as an acid solvent because of its acidic properties. This study was aimed to explore the most potential agroindustrial wastewaters in dissolving phosphate rock through acidulation in the laboratory scale. The experiment was arranged in a factorial. The first factor was origined of phosphate rock (Sukabumi, west Java and Selagailingga, central Lampung and the second factor was solvent types (agroindustrial wastewaters which were pineapple, tapioca, tofu industry, and palm oil as well as conventional acid solvents which were HCl, H2SO4, and CH3COOH. The incubation processes were 0, 1, 2, and 3 months. The results showed that agroindustrial wastewaters that have the highest potency to solubize phosphate rock was industrial tofu wastewaters and followed by industrial wastewaters of tapioca, palm oil, and pineapple. Both the conventional acid and agroindustrial wastewaters solvent had a big potency to solubilize phosphate rock, however, its highest soluble P-value did not match with the ISO criteria for phosphate fertilizers Quality I (SNI because it did not reach the solubility of 80% of its total P2O5, but it has been qualified as a fertilizer both the quality phosphate A, B, and C (SNI.

  6. Effect of boron and phosphate compounds on physical, mechanical, and fire properties of wood-polypropylene composites

    Science.gov (United States)

    Nadir Ayrilmis; Turgay Akbulut; Turker Dundar; Robert H. White; Fatih Mengeloglu; Umit Buyuksari; Zeki Candan; Erkan Avci

    2012-01-01

    Physical, mechanical, and fire properties of the injection-molded wood flour/polypropylene composites incorporated with different contents of boron compounds; borax/boric acid and zinc borate, and phosphate compounds; mono and diammonium phosphates were investigated. The effect of the coupling agent content, maleic anhydride-grafted polypropylene, on the properties of...

  7. Isolation and phosphate-solubilizing ability of a fungus, Penicillium sp. from soil of an alum mine.

    Science.gov (United States)

    Chai, Bo; Wu, Yan; Liu, Pengming; Liu, Biao; Gao, Meiying

    2011-02-01

    The use of microorganisms to solubilize elemental phosphorus from insoluble rock phosphate is a promising method to greatly reduce not only environmental pollution but also production costs. Phosphate-solubilizing microorganisms were isolated from soils in China, and a fungus strain (PSM11-5) from a soil sample from an alum mine, with the highest phosphate solubilization potential, was selected and identified as a Penicillium sp. Strain PSM11-5 could grow in buffered medium with pH values between 3.0 and 8.0 and showed phosphate solubilizing activity at pH values from 5.0 to 8.0. It also exhibited a degree of tolerance to the heavy metal ions, Cd(2+), Co(2+), and Cr(6+). PSM11-5 could rapidly solubilize tricalcium phosphate, and a high phosphate-solubilizing efficiency of 98% was achieved in an optimized medium. The strain could solubilize rock phosphate and aluminum phosphate with a solubilizing efficiency of approximately 74.5%, but did not solubilize iron phosphate. Solubilization of phosphate depended on acidification. Analysis of PSM11-5 culture supernatants by capillary electrophoresis showed that tricalcium phosphate was solubilized to PO(4) (3-) and Ca(2+) , and that the organic acid produced by the fungus was mainly gluconic acid at approximately ca. 13 g l(-1). In addition, PSM11-5 produced ca. 830 mg l(-1) of citric acid when it was used to solubilize rock phosphate. These excellent properties of strain PSM11-5 suggest that the fungus has potential for agricultural and industrial utilization. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Electrochemical Induced Calcium Phosphate Precipitation

    NARCIS (Netherlands)

    Lei, Yang; Song, Bingnan; Weijden, van der Renata D.; Saakes, M.; Buisman, Cees J.N.

    2017-01-01

    Phosphorus (P) is an essential nutrient for living organisms and cannot be replaced or substituted. In this paper, we present a simple yet efficient membrane free electrochemical system for P removal and recovery as calcium phosphate (CaP). This method relies on in situ formation of hydroxide

  9. Phosphate Recognition in Structural Biology

    NARCIS (Netherlands)

    Hirsch, Anna K.H.; Fischer, Felix R.; Diederich, François

    2007-01-01

    Drug-discovery research in the past decade has seen an increased selection of targets with phosphate recognition sites, such as protein kinases and phosphatases, in the past decade. This review attempts, with the help of database-mining tools, to give an overview of the most important principles in

  10. Toward an In Vivo Dissolution Methodology: A Comparison of Phosphate and Bicarbonate Buffers

    Science.gov (United States)

    Sheng, Jennifer J.; McNamara, Daniel P.; Amidon, Gordon L.

    2011-01-01

    Purpose To evaluate the difference between the pharmaceutical phosphate buffers and the gastrointestinal bicarbonates in dissolution of ketoprofen and indomethacin, to illustrate the dependence of buffer differential on biopharmaceutical properties of BCS II weak acids, and to recommend phosphate buffers equivalent to bicarbonates. Methods The intrinsic dissolution rates of, ketoprofen and indomethacin, were experimentally measured using rotating disk method at 37°C in USP SIF/FaSSIF and various concentrations of bicarbonates. Theoretical models including an improved reaction plane model and a film model were applied to estimate the surrogate phosphate buffers equivalent to the bicarbonates. Results Experimental results show that the intrinsic dissolution rates of ketoprofen and indomethacin, in USP and FaSSIF phosphate buffers are 1.5–3.0 times of that in the 15 mM bicarbonates. Theoretical analysis demonstrates that the buffer differential is largely dependent on the drug pKa and secondly on solubility, and weakly dependent on the drug diffusivity. Further, in accordance with the drug pKa, solubility and diffusivity, simple phosphate surrogate was proposed to match an average bicarbonate value (15 mM) of the upper gastrointestinal region. Specifically, phosphate buffers of 13–15 mM and 3–4 mM were recommended for ketoprofen and indomethacin, respectively. For both ketoprofen and indomethacin, the intrinsic dissolution using the phosphate surrogate buffers closely approximated the 15 mM bicarbonate buffer. Conclusions This work demonstrates the substantial difference between pharmaceutical phosphates and physiological bicarbonates in determining the drug intrinsic dissolution rates of BCS II weak acids, such as ketoprofen and indomethacin. Surrogate phosphates were recommended in order to closely reflect the in vivo dissolution of ketoprofen and indomethacin in gastrointestinal bicarbonates, which has significant implications for defining buffer systems for

  11. Final Report - Assessment of Potential Phosphate Ion-Cementitious Materials Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Naus, Dan J [ORNL; Mattus, Catherine H [ORNL; Dole, Leslie Robert [ORNL

    2007-06-01

    The objectives of this limited study were to: (1) review the potential for degradation of cementitious materials due to exposure to high concentrations of phosphate ions; (2) provide an improved understanding of any significant factors that may lead to a requirement to establish exposure limits for concrete structures exposed to soils or ground waters containing high levels of phosphate ions; (3) recommend, as appropriate, whether a limitation on phosphate ion concentration in soils or ground water is required to avoid degradation of concrete structures; and (4) provide a "primer" on factors that can affect the durability of concrete materials and structures in nuclear power plants. An assessment of the potential effects of phosphate ions on cementitious materials was made through a review of the literature, contacts with concrete research personnel, and conduct of a "bench-scale" laboratory investigation. Results of these activities indicate that: no harmful interactions occur between phosphates and cementitious materials unless phosphates are present in the form of phosphoric acid; phosphates have been incorporated into concrete as set retarders, and phosphate cements have been used for infrastructure repair; no standards or guidelines exist pertaining to applications of reinforced concrete structures in high-phosphate environments; interactions of phosphate ions and cementitious materials has not been a concern of the research community; and laboratory results indicate similar performance of specimens cured in phosphate solutions and those cured in a calcium hydroxide solution after exposure periods of up to eighteen months. Relative to the "primer," a separate NUREG report has been prepared that provides a review of pertinent factors that can affect the durability of nuclear power plant reinforced concrete structures.

  12. 21 CFR 184.1301 - Ferric phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ferric phosphate. 184.1301 Section 184.1301 Food... Specific Substances Affirmed as GRAS § 184.1301 Ferric phosphate. (a) Ferric phosphate (ferric orthophosphate, iron (III) phosphate, FePO4·xH2O, CAS Reg. No. 10045-86-0) is an odorless, yellowish-white to...

  13. Phosphate Solubilization Potentials of Rhizosphere Isolates from Central Anatolia (Turkey)

    Science.gov (United States)

    Ogut, M.; Er, F.

    2009-04-01

    Plant available-phosphorus (P) is usually low in Anatolian soils due mainly to the precipitation as calcium (Ca) and magnesium (Mg) phosphates in alkaline conditions. Phosphate solubilizing microorganisms (PSM) can enhance plant P-availability by dissolving the hardly soluble-P within the rhizosphere, which is the zone that surrounds the plant roots. PSM's can be used as seed- or soil-inocula to increase plant P-uptake and the overall growth. A total of 162 PSM's were isolated from the rhizosphere of wheat plants excavated from different fields located along a 75 km part of a highway in Turkey. The mean, the standart deviation, and the median for solubilized-P (ppm) in a 24 h culture in a tricalcium phosphate broth were 681, 427, and 400 for glucose; 358, 266, and 236 for sucrose; and 102, 117, and 50 for starch, respectively. There was not a linear relationship between the phosphate solubilized in the liquid cultures and the solubilization index obtained in the Pikovskaya's agar. Nine isolates representing both weak and strong solubilizers [Bacillus megaterium (5), Bacillus pumilis (1), Pseudomonas syringae pv. phaseolica (1), Pseudomonas fluorescens (1), Arthrobacter aurescens (1) as determined by the 16S rRNA gene sequence analysis] were further studied in a five day incubation. Pseudomonas syringae pv. phaseolica solubilized statistically (Pphosphate (409 ppm) than all the other strains did. There was not a statistically significant (Pphosphate solubilizing strains variably produced gluconic, 2-keto-D-gluconic, glycolic, acetic and butyric acids. The organic acids produced by these microorganisms seem to be the major source of phosphate solubilization in vitro.

  14. 21 CFR 182.1778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium phosphate. 182.1778 Section 182.1778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Substances § 182.1778 Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b...

  15. 21 CFR 582.6778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium phosphate. 582.6778 Section 582.6778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b) Conditions of use. This...

  16. 21 CFR 182.6285 - Dipotassium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Dipotassium phosphate. 182.6285 Section 182.6285 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... Dipotassium phosphate. (a) Product. Dipotassium phosphate. (b) Conditions of use. This substance is generally...

  17. 40 CFR 721.5995 - Polyalkyl phosphate.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polyalkyl phosphate. 721.5995 Section... Substances § 721.5995 Polyalkyl phosphate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a polyalkyl phosphate (PMN P-95-1772) is...

  18. 21 CFR 182.6290 - Disodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Disodium phosphate. 182.6290 Section 182.6290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... phosphate. (a) Product. Disodium phosphate. (b) Conditions of use. This substance is generally recognized as...

  19. 21 CFR 182.6778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium phosphate. 182.6778 Section 182.6778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b) Conditions of use. This substance...

  20. 21 CFR 182.1217 - Calcium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium phosphate. 182.1217 Section 182.1217 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Substances § 182.1217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic). (b...

  1. 21 CFR 582.6285 - Dipotassium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dipotassium phosphate. 582.6285 Section 582.6285 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Dipotassium phosphate. (a) Product. Dipotassium phosphate. (b) Conditions of use. This substance is generally...

  2. Mineral resource of the month: Phosphate rock

    Science.gov (United States)

    Jasinski, Stephen M.

    2013-01-01

    As a mineral resource, “phosphate rock” is defined as unprocessed ore and processed concentrates that contain some form of apatite, a group of calcium phosphate minerals that is the primary source for phosphorus in phosphate fertilizers, which are vital to agriculture.

  3. 21 CFR 582.1217 - Calcium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium phosphate. 582.1217 Section 582.1217 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic). (b...

  4. 21 CFR 582.1141 - Ammonium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ammonium phosphate. 582.1141 Section 582.1141 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1141 Ammonium phosphate. (a) Product. Ammonium phosphate (mono- and dibasic). (b) Conditions...

  5. 21 CFR 582.1778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium phosphate. 582.1778 Section 582.1778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1778 Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b...

  6. 21 CFR 582.6290 - Disodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Disodium phosphate. 582.6290 Section 582.6290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Disodium phosphate. (a) Product. Disodium phosphate. (b) Conditions of use. This substance is generally...

  7. Biodiversity of the phosphate solubilizing microorganisms (PSMs ...

    African Journals Online (AJOL)

    The plant rhizosphere microorganisms having the phosphate solubilizing capacity can convert the insoluble soil organic and inorganic phosphates into a soluble form and make the phosphorus (P) available to the plant. With the objective of evaluating the phosphate solubilizing microorganism populations under the rice ...

  8. Calcium Phosphate Bone Cements Including Sugar Surfactants: Part One—Porosity, Setting Times and Compressive Strength

    Directory of Open Access Journals (Sweden)

    Juliette Fitremann

    2010-09-01

    Full Text Available Addition of sugar surfactants, sucrose fatty acid esters and alkylpolyglucosides, to calcium phosphate cement designed for bone reconstruction is described. Thanks to their surface activity and through their adsorption at the surface of the calcium phosphate particles, they both induced a strong increase in the porosity (quantified by Image Analysis and brought a very good workability. Other properties typically studied for these cements are reported, including setting times, compressive strength, cohesion in water, and effect of sterilization on these properties. The whole study brought good insight in the interest of adding these mild surfactants to improve several properties of the calcium phosphate cement, without impairing their function.

  9. Calcium Phosphate Bone Cements Including Sugar Surfactants: Part One-Porosity, Setting Times and Compressive Strength.

    Science.gov (United States)

    Bercier, Ariane; Gonçalves, Stéphane; Lignon, Olivier; Fitremann, Juliette

    2010-09-30

    Addition of sugar surfactants, sucrose fatty acid esters and alkylpolyglucosides, to calcium phosphate cement designed for bone reconstruction is described. Thanks to their surface activity and through their adsorption at the surface of the calcium phosphate particles, they both induced a strong increase in the porosity (quantified by Image Analysis) and brought a very good workability. Other properties typically studied for these cements are reported, including setting times, compressive strength, cohesion in water, and effect of sterilization on these properties. The whole study brought good insight in the interest of adding these mild surfactants to improve several properties of the calcium phosphate cement, without impairing their function.

  10. Preparation of titanium phosphates with additives in hydrothermal process and their powder properties for cosmetics.

    Science.gov (United States)

    Onoda, Hiroaki; Yamaguchi, Taisuke

    2013-04-01

    In this study, titanium phosphates were prepared from titanium chloride and phosphoric acid, sodium pyrophosphate and sodium triphosphate solutions with water retention compounds in hydrothermal process as a novel white pigment for cosmetics. Their chemical composition, powder properties, photo catalytic activity, water retention and smoothness were studied. The addition of glycerin in the preparation from sodium pyrophosphate has the useful method to obtain homogenized spherical particles of titanium phosphate pigments for the cosmetics. These titanium phosphates had less photo catalytic activity to protect the sebum on the skin. © 2012 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  11. Calcium Phosphate Bone Cements Including Sugar Surfactants: Part Two—Injectability, Adhesive Properties and Biocompatibility

    OpenAIRE

    Fabienne Briand-Mesange; Stéphane Gonçalves; Helène Autefage; Ariane Bercier; Olivier Lignon; Juliette Fitremann

    2010-01-01

    Addition of sugar surfactants, sucrose fatty acid esters and alkylpolyglucosides to a calcium phosphate cement, designed for bone reconstruction, is described. Thanks to their adsorption at the surface of the calcium phosphate particles, the sugar surfactants allowed a full injectability and brought a very good workability. Injectability was measured by monitoring force-distance curves. With some of the selected sugar surfactants adhesive properties of the cement pastes were also observed, wh...

  12. Calcium Phosphate Bone Cements Including Sugar Surfactants: Part One?Porosity, Setting Times and Compressive Strength

    OpenAIRE

    Juliette Fitremann; Ariane Bercier; Olivier Lignon; Stéphane Gonçalves

    2010-01-01

    Addition of sugar surfactants, sucrose fatty acid esters and alkylpolyglucosides, to calcium phosphate cement designed for bone reconstruction is described. Thanks to their surface activity and through their adsorption at the surface of the calcium phosphate particles, they both induced a strong increase in the porosity (quantified by Image Analysis) and brought a very good workability. Other properties typically studied for these cements are reported, including setting times, compressive str...

  13. influence de la phosphatation au zinc sur la resistance a la co

    African Journals Online (AJOL)

    AKA Boko Mathieu

    cationiques (Zn2+, Fe2+) capables de réagir avec la surface métallique conduisant à la formation des cristaux sur cette surface. Les principaux constituants sont : - l'acide phosphorique libre H3PO4 ;. - le phosphate mono zincique Zn (H2PO4)2 ;. - l'accélérateur NaNO2. En effet, trois types de phosphatation peuvent exister ...

  14. Production of nanaomycin and other antibiotics by phosphate-depressed fermentation using phosphate-trapping agents.

    Science.gov (United States)

    Masuma, R; Tanaka, Y; Tanaka, H; Omura, S

    1986-11-01

    Nanaomycin production by Streptomyces rosa subsp. notoensis in complex media was inhibited by exogenously supplied inorganic phosphate. The inhibition was reversed by phosphate-trapping agents such as allophane and aluminum oxide. Under such condition nanaomycin production increased to the control level, and the phosphate content dropped down to the unsupplemented level. When allophane was added to conventional complex media containing nutrient-derived inorganic phosphate, the production of nanaomycin and several other antibiotics, which are subject to phosphate regulation, was enhanced several fold with the simultaneous reduction of free phosphate. The term "phosphate-depressed fermentation" is proposed for this technique.

  15. The Use of Rock Phosphate and Phosphate Solubilising Fungi ...

    African Journals Online (AJOL)

    User

    planted 40 days after sowing rice seed and 80 DAS- pigeon pea planted 80 days after sowing rice). In the second year, phosphate fertilizer was the main plot treatment, consisting of (0 kg/ha P2O5, 45 kg/ha P2O5 RP, 90 kg/ha. P2O5 RP and 45 kg/ha P2O5 TSP), and the subplot treatment was inoculated and uninoculated ...

  16. Biosynthesis of ribose-5-phosphate and erythrose-4-phosphate in archaea: a phylogenetic analysis of archaeal genomes

    Directory of Open Access Journals (Sweden)

    Tim Soderberg

    2005-01-01

    Full Text Available A phylogenetic analysis of the genes encoding enzymes in the pentose phosphate pathway (PPP, the ribulose monophosphate (RuMP pathway, and the chorismate pathway of aromatic amino acid biosynthesis, employing data from 13 complete archaeal genomes, provides a potential explanation for the enigmatic phylogenetic patterns of the PPP genes in archaea. Genomic and biochemical evidence suggests that three archaeal species (Methanocaldococcus jannaschii, Thermoplasma acidophilum and Thermoplasma volcanium produce ribose-5-phosphate via the nonoxidative PPP (NOPPP, whereas nine species apparently lack an NOPPP but may employ a reverse RuMP pathway for pentose synthesis. One species (Halobacterium sp. NRC-1 lacks both the NOPPP and the RuMP pathway but may possess a modified oxidative PPP (OPPP, the details of which are not yet known. The presence of transketolase in several archaeal species that are missing the other two NOPPP genes can be explained by the existence of differing requirements for erythrose-4-phosphate (E4P among archaea: six species use transketolase to make E4P as a precursor to aromatic amino acids, six species apparently have an alternate biosynthetic pathway and may not require the ability to make E4P, and one species (Pyrococcus horikoshii probably does not synthesize aromatic amino acids at all.

  17. THERMODINAMIC PARAMETERS ON THE SORPTION OF PHOSPHATE IONS BY MONTMORILLONITE

    Directory of Open Access Journals (Sweden)

    Ikhsan Jaslin

    2016-04-01

    Full Text Available The sorption of phosphate by montmorillonite at 10, 30, and 50 oC were investigated aiming to mainly determine thermodynamic parameters for the formation of surface complexes in the adsorption of phosphate ions by montmorillonite. Data were collected by adsorption edge experiments investigating the effect of pH, adsorption isotherms enabling the effect of sorbate concentration, and acid-base titration calculating protons released or taken up by adsorption process. Data analysis was carried out using surface complexation model to fit the data collected in this study using the parameters obtained from previous study, as well as to calculate the values of ΔH and ΔS. Previous study reported that phosphate ions formed two outer-sphere surface complexes with active sites of montmorillonite through hydrogen bonding. In the first complex,  [(XH0– H2L─]─, the phosphate was held to permanent-charge X─ sites on the tetrahedral siloxane faces, and the second complex, [[(SO─(SOH]– – [H2L]─] 2─ was formed through the interaction between the phosphate and variable charge surface hydroxyl groups at the edges of montmorillonite crystals and on the octahedral alumina faces. The values of ΔH for the first and second reactions are 39.756 and 3.765x10-7 kJ mol‒1 respectively. Since both reactions have positive enthalpy values, it can be concluded that the reactions are endothermic. Large energy for the first reaction is needed by X─  sites (permanent negatively charge sites of montmorillonite to be partially desolvated, on which K+ or other surface cations are replaced by H+ ions in the surface protonated process, and are then ready to interact phosphate ions in the solution. Small values of ΔH for the second reactions indicates that hydrogen bonds formed by phosphate and SOH sites in the second reaction are easily broken out, and the phosphate can easily desorbed from the surface. The values of ΔS for the first and second reactions are

  18. Rapid degradation of zinc oxide nanoparticles by phosphate ions

    Directory of Open Access Journals (Sweden)

    Rudolf Herrmann

    2014-11-01

    Full Text Available Zinc oxide nanoparticles are highly sensitive towards phosphate ions even at pH 7. Buffer solutions and cell culture media containing phosphate ions are able to destroy ZnO nanoparticles within a time span from less than one hour to one day. The driving force of the reaction is the formation of zinc phosphate of very low solubility. The morphology of the zinc oxide particles has only a minor influence on the kinetics of this reaction. Surface properties related to different production methods and the presence and absence of labelling with a perylene fluorescent dye are more important. Particles prepared under acidic conditions are more resistant than those obtained in basic or neutral reaction medium. Surprisingly, the presence of a SiO2 coating does not impede the degradation of the ZnO core. In contrast to phosphate ions, β-glycerophosphate does not damage the ZnO nanoparticles. These findings should be taken into account when assessing the biological effects or the toxicology of zinc oxide nanoparticles.

  19. Utilization of the phosphorus in Langebaan rock phosphate by ...

    African Journals Online (AJOL)

    (1976) evaluated two Christmas Island rock phosphates; the raw rock phosphate dried and ground to 100 mesh (C-Grade. Phosphate) and calcined C-Grade Phosphate. Both C-Grade. Phosphates were inferior to feed-grade dicalcium phosphate as. P sources for growing sheep given a low-P diet. Nevertheless, they were ...

  20. Multimodal pore formation in calcium phosphate cements.

    Science.gov (United States)

    Lodoso-Torrecilla, Irene; van Gestel, Nicole A P; Diaz-Gomez, Luis; Grosfeld, Eline-Claire; Laperre, Kjell; Wolke, Joop G C; Smith, Brandon T; Arts, Jacobus J; Mikos, Antonios G; Jansen, John A; Hofmann, Sandra; van den Beucken, Jeroen J J P

    2017-09-23

    Calcium phosphate cements (CPCs) are commonly used as bone substitute materials. However, their slow degradation rate and lack of macroporosity hinders new bone formation. Poly(dl-lactic-co-glycolic acid) (PLGA) incorporation is of great interest as, upon degradation, produces acidic by-products that enhance CPC degradation. Yet, new bone formation is delayed until PLGA degradation occurs a few weeks after implantation. Therefore, the aim of this study was to accelerate the early stage pore formation within CPCs in vitro. With that purpose, we incorporated the water-soluble porogen sucrose at different weight percentages (10 or 20 wt %) to CPC and CPC/PLGA composites. The results revealed that incorporation of sucrose porogens increased mass loss within the first week of in vitro degradation in groups containing sucrose compared to control groups. After week 1, a further mass loss was observed related to PLGA and CPC degradation. Macroporosity analysis confirmed that macroporosity formation is influenced by the dissolution of sucrose at an early stage and by the degradation of PLGA and CPC at a later stage. We concluded that the combination of sucrose and PLGA porogens in CPC is a promising approach to promote early stage bone tissue ingrowth and complete replacement of CPC through multimodal pore formation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2017. © 2017 Wiley Periodicals, Inc.

  1. Hybrid calcium phosphate coatings for implants

    Science.gov (United States)

    Malchikhina, Alena I.; Shesterikov, Evgeny V.; Bolbasov, Evgeny N.; Ignatov, Viktor P.; Tverdokhlebov, Sergei I.

    2016-08-01

    Monophasic biomaterials cannot provide all the necessary functions of bones or other calcined tissues. It is necessary to create for cancer patients the multiphase materials with the structure and composition simulating the natural bone. Such materials are classified as hybrid, obtained by a combination of chemically different components. The paper presents the physical, chemical and biological studies of coatings produced by hybrid technologies (HT), which combine primer layer and calcium phosphate (CaP) coating. The first HT type combines the method of vacuum arc titanium primer layer deposition on a stainless steel substrate with the following micro-arc oxidation (MAO) in phosphoric acid solution with addition of calcium compounds to achieve high supersaturated state. MAO CaP coatings feature high porosity (2-8%, pore size 5-7 µm) and surface morphology with the thickness greater than 5 µm. The thickness of Ti primer layer is 5-40 µm. Amorphous MAO CaP coating micro-hardness was measured at maximum normal load Fmax = 300 mN. It was 3.1 ± 0.8 GPa, surface layer elasticity modulus E = 110 ± 20 GPa, roughness Ra = 0.9 ± 0.1 µm, Rz = 7.5 ± 0.2 µm, which is less than the titanium primer layer roughness. Hybrid MAO CaP coating is biocompatible, able to form calcium phosphates from supersaturated body fluid (SBF) solution and also stimulates osteoinduction processes. The second HT type includes the oxide layer formation by thermal oxidation and then CaP target radio frequency magnetron sputtering (RFMS). Oxide-RFMS CaP coating is a thin dense coating with good adhesion to the substrate material, which can be used for metal implants. The RFMS CaP coating has thickness 1.6 ± 0.1 µm and consists of main target elements calcium and phosphorus and Ca/P ratio 2.4. The second HT type can form calcium phosphates from SBF solution. In vivo study shows that hybrid RFMS CaP coating is biocompatible and produces fibrointegration processes.

  2. Chemical immobilization of Pb, Cu, and Cd by phosphate materials and calcium carbonate in contaminated soils.

    Science.gov (United States)

    Huang, Guoyong; Su, Xiaojuan; Rizwan, Muhammad Shahid; Zhu, Yifei; Hu, Hongqing

    2016-08-01

    Soil contamination with toxic metals has increasingly become a global concern over the past few decades. Phosphate and carbonate compounds are good passivation materials for Pb immobilization, while the effect of phosphate and carbonate on the immobilization of multiple heavy metals (Pb, Cu, and Cd) in contaminated soils was seldom investigated. In this study, bone meal (BM), phosphate rock (PR), oxalic acid-activated phosphate rock (APR), super phosphate (SP), and calcium carbonate (CC) were added to the contaminated soils to evaluate the effect of phosphate materials and calcium carbonate on the immobilization of Pb, Cu, and Cd. The results showed that the pH of the treated soils increased 1.3-2.7, except SP which decreased 0.5 at most. Compared to the control treatment, all phosphates and calcium carbonate added to the polluted soils increased the fraction of residual metals, and the application of APR, PR, BM, and CC significantly reduced exchangeable and carbonate-bound fraction metals. PR and APR were the most effective for the immobilization of Pb, Cu, and Cd in the soils among these materials. Moreover, the concentrations of all metals in the toxicity characteristic leaching procedure (TCLP) leachate decreased with increasing amounts of amendments, and the concentrations of Pb in the TCLP leachate for soils treated with PR and APR were below the nonhazardous regulatory limit of 5 mg L(-1) (US Environmental Protection Agency). Based on our results, phosphate rock and oxalic acid-activated phosphate rock are effective in the immobilization of multiple metals by reducing their mobility in the co-contaminated soils.

  3. Structural characterization of a ribose-5-phosphate isomerase B from the pathogenic fungus Coccidioides immitis

    Directory of Open Access Journals (Sweden)

    Leibly David J

    2011-10-01

    Full Text Available Abstract Background Ribose-5-phosphate isomerase is an enzyme that catalyzes the interconversion of ribose-5-phosphate and ribulose-5-phosphate. This family of enzymes naturally occurs in two distinct classes, RpiA and RpiB, which play an important role in the pentose phosphate pathway and nucleotide and co-factor biogenesis. Results Although RpiB occurs predominantly in bacteria, here we report crystal structures of a putative RpiB from the pathogenic fungus Coccidioides immitis. A 1.9 Å resolution apo structure was solved by combined molecular replacement and single wavelength anomalous dispersion (SAD phasing using a crystal soaked briefly in a solution containing a high concentration of iodide ions. RpiB from C. immitis contains modest sequence and high structural homology to other known RpiB structures. A 1.8 Å resolution phosphate-bound structure demonstrates phosphate recognition and charge stabilization by a single positively charged residue whereas other members of this family use up to five positively charged residues to contact the phosphate of ribose-5-phosphate. A 1.7 Å resolution structure was obtained in which the catalytic base of C. immitis RpiB, Cys76, appears to form a weakly covalent bond with the central carbon of malonic acid with a bond distance of 2.2 Å. This interaction may mimic that formed by the suicide inhibitor iodoacetic acid with RpiB. Conclusion The C. immitis RpiB contains the same fold and similar features as other members of this class of enzymes such as a highly reactive active site cysteine residue, but utilizes a divergent phosphate recognition strategy and may recognize a different substrate altogether.

  4. Structural characterization of a ribose-5-phosphate isomerase B from the pathogenic fungus Coccidioides immitis.

    Science.gov (United States)

    Edwards, Thomas E; Abramov, Ariel B; Smith, Eric R; Baydo, Ruth O; Leonard, Jess T; Leibly, David J; Thompkins, Kaitlin B; Clifton, Matthew C; Gardberg, Anna S; Staker, Bart L; Van Voorhis, Wesley C; Myler, Peter J; Stewart, Lance J

    2011-10-13

    Ribose-5-phosphate isomerase is an enzyme that catalyzes the interconversion of ribose-5-phosphate and ribulose-5-phosphate. This family of enzymes naturally occurs in two distinct classes, RpiA and RpiB, which play an important role in the pentose phosphate pathway and nucleotide and co-factor biogenesis. Although RpiB occurs predominantly in bacteria, here we report crystal structures of a putative RpiB from the pathogenic fungus Coccidioides immitis. A 1.9 Å resolution apo structure was solved by combined molecular replacement and single wavelength anomalous dispersion (SAD) phasing using a crystal soaked briefly in a solution containing a high concentration of iodide ions. RpiB from C. immitis contains modest sequence and high structural homology to other known RpiB structures. A 1.8 Å resolution phosphate-bound structure demonstrates phosphate recognition and charge stabilization by a single positively charged residue whereas other members of this family use up to five positively charged residues to contact the phosphate of ribose-5-phosphate. A 1.7 Å resolution structure was obtained in which the catalytic base of C. immitis RpiB, Cys76, appears to form a weakly covalent bond with the central carbon of malonic acid with a bond distance of 2.2 Å. This interaction may mimic that formed by the suicide inhibitor iodoacetic acid with RpiB. The C. immitis RpiB contains the same fold and similar features as other members of this class of enzymes such as a highly reactive active site cysteine residue, but utilizes a divergent phosphate recognition strategy and may recognize a different substrate altogether.

  5. Inadequate awareness among chronic kidney disease patients regarding food and drinks containing artificially added phosphate.

    Science.gov (United States)

    Shutto, Yoshiko; Shimada, Michiko; Kitajima, Maiko; Yamabe, Hideaki; Saitoh, Yoko; Saitoh, Hisao; Razzaque, Mohammed S

    2013-01-01

    Hyperphosphatemia is an important determinant of morbidity and mortality in patients with chronic kidney disease (CKD). Patients with CKD are advised to consume a low phosphate diet and are often prescribed phosphate-lowering drug therapy. However, commercially processed food and drinks often contain phosphate compounds, but the phosphate level is not usually provided in the ingredient list, which makes it difficult for CKD patients to choose a correct diet. We conducted a survey of the awareness of food/beverages containing artificially added phosphate among CKD patients undergoing hemodialysis. The subjects were 153 patients (77 males and 76 females; average age 56±11 years) who were randomly selected from the Dialysis Center of Hirosaki City, Japan. The subjects were provided with a list of questions. The survey results showed that 93% of the subjects were aware of the presence of high sugar content in soda, whereas only 25% were aware of the presence of phosphate (phosphoric acid) in such drinks. Despite 78% of the subjects being aware of the detrimental effects of consumption of a high phosphate diet, 43% drank at least 1 to 5 cans of soda per week and about 17% consumed "fast food" once each week. We also assessed the immediate effects of high-phosphate containing carbonated soda consumption by determining urinary calcium, phosphate, protein and sugar contents in overnight fasted healthy volunteers (n = 55; average age 20.7±0.3 years old, 20 males and 35 females). Significantly higher urinary calcium (adjusted using urinary creatinine) excretion was found 2 h after consuming 350 ml of carbonated soda compared to the fasting baseline level (0.15±0.01 vs. 0.09±0.01, p = 0.001). Our survey results suggest that CKD patients undergoing hemodialysis are not adequately aware of the hidden source of phosphate in their diet, and emphasize the need for educational initiatives to raise awareness of this issue among CKD patients.

  6. The return of metabolism: biochemistry and physiology of the pentose phosphate pathway

    Science.gov (United States)

    Stincone, Anna; Prigione, Alessandro; Cramer, Thorsten; Wamelink, Mirjam M. C.; Campbell, Kate; Cheung, Eric; Olin-Sandoval, Viridiana; Grüning, Nana-Maria; Krüger, Antje; Alam, Mohammad Tauqeer; Keller, Markus A.; Breitenbach, Michael; Brindle, Kevin M.; Rabinowitz, Joshua D.; Ralser, Markus

    2015-01-01

    The pentose phosphate pathway (PPP) is a fundamental component of cellular metabolism. The PPP is important to maintain carbon homoeostasis, to provide precursors for nucleotide and amino acid biosynthesis, to provide reducing molecules for anabolism, and to defeat oxidative stress. The PPP shares reactions with the Entner–Doudoroff pathway and Calvin cycle and divides into an oxidative and non-oxidative branch. The oxidative branch is highly active in most eukaryotes and converts glucose 6-phosphate into carbon dioxide, ribulose 5-phosphate and NADPH. The latter function is critical to maintain redox balance under stress situations, when cells proliferate rapidly, in ageing, and for the ‘Warburg effect’ of cancer cells. The non-oxidative branch instead is virtually ubiquitous, and metabolizes the glycolytic intermediates fructose 6-phosphate and glyceraldehyde 3-phosphate as well as sedoheptulose sugars, yielding ribose 5-phosphate for the synthesis of nucleic acids and sugar phosphate precursors for the synthesis of amino acids. Whereas the oxidative PPP is considered unidirectional, the non-oxidative branch can supply glycolysis with intermediates derived from ribose 5-phosphate and vice versa, depending on the biochemical demand. These functions require dynamic regulation of the PPP pathway that is achieved through hierarchical interactions between transcriptome, proteome and metabolome. Consequently, the biochemistry and regulation of this pathway, while still unresolved in many cases, are archetypal for the dynamics of the metabolic network of the cell. In this comprehensive article we review seminal work that led to the discovery and description of the pathway that date back now for 80 years, and address recent results about genetic and metabolic mechanisms that regulate its activity. These biochemical principles are discussed in the context of PPP deficiencies causing metabolic disease and the role of this pathway in biotechnology, bacterial and

  7. Ferrocenylphosphonic acid

    Directory of Open Access Journals (Sweden)

    Bao-Zhang Yang

    2011-08-01

    Full Text Available In the title compound, [Fe(C5H5(C5H6O3P], the phosphate group is bonded to the ferrocene unit with a P—C bond length of 1.749 (3 Å. In the crystal, six ferrocenylphosphonic acid molecules are connected by 12 strong intermolecular O—H...O hydrogen bonds, leading to the formation of a highly distorted octahedral cage. The volume of the octahedral cage is about 270 Å3.

  8. Discovery of 3-arylpropionic acids as potent agonists of sphingosine-1-phosphate receptor-1 (S1P1) with high selectivity against all other known S1P receptor subtypes.

    Science.gov (United States)

    Yan, Lin; Huo, Pei; Doherty, George; Toth, Lesile; Hale, Jeffrey J; Mills, Sander G; Hajdu, Richard; Keohane, Carol A; Rosenbach, Mark J; Milligan, James A; Shei, Gan-Ju; Chrebet, Gary; Bergstrom, James; Card, Deborah; Quackenbush, Elizabeth; Wickham, Alexandra; Mandala, Suzanne M

    2006-07-15

    A series of 3-arylpropionic acids were synthesized as S1P1 receptor agonists. Structure-activity relationship studies on the pendant phenyl ring revealed several structural features offering selectivity of S1P1 binding against S1P2-5. These highly selective S1P1 agonists induced peripheral blood lymphocyte lowering in mice and one of them was found to be efficacious in a rat skin transplantation model, supporting that S1P1 agonism is primarily responsible for the immunosuppressive efficacy observed in preclinical animal models.

  9. Mécanismes et cinétique de dissolution de matériaux phosphatés cristallisés et amorphes en milieux acides chlorhydrique et citrique.

    OpenAIRE

    Thirioux, Laurence

    1990-01-01

    L'INFLUENCE DES LIGANDS ORGANIQUES SUR LA VITESSE DE DISSOLUTION DE LA FLUORAPATITE (CA#1#0(PO#4)#6F#2) ET DE VERRES SILICOPHOSPHATES (SI-P-CA-MG) A PU ETRE APPRECIEE PAR UNE APPROCHE A L'ECHELLE DU SOLIDE ET DES SOLUTIONS. POUR CE FAIRE, DES ESSAIS PARALLELES ONT ETE MENES EN MILIEUX ACIDES CITRIQUE ET CHLORHYDRIQUE DE PH INITIAL IDENTIQUE. LA PRESENCE DE LIGANDS ORGANIQUES DANS LE MILIEU D'ATTAQUE NE MODIFIE PAS LA VITESSE DE DISSOLUTION DE LA FLUORAPATITE. EN SOLUTION CHLORHYDRIQUE, CE MEC...

  10. Evidence of a phosphate-transporter system in the inner membrane of isolated mitochondria.

    Science.gov (United States)

    Tyler, D D

    1969-03-01

    1. The organic mercurial sodium mersalyl, formaldehyde, dicyclohexylcarbodiimide and tributyltin each blocked respiratory-chain-linked ATP synthesis in rat liver mitochondria. 2. Mersalyl and formaldehyde also blocked a number of other processes dependent on the entry of inorganic phosphate into mitochondria, including mitochondrial respiration and swelling stimulated by cations and phosphate, the substrate-level phosphorylation reaction of the citric acid cycle, and swelling in ammonium phosphate. 3. Dicyclohexylcarbodi-imide and tributyltin did not inhibit the entry of phosphate into mitochondria. 4. Mersalyl and formaldehyde had a relatively slight effect on succinate oxidation and swelling stimulated by cations when phosphate was replaced by acetate, on succinate oxidation stimulated by uncoupling agents, and on swelling in solutions of ammonium salts other than phosphate or arsenate. 5. Formaldehyde blocked the oxidation of NAD-linked substrates in mitochondria treated with 2,4-dinitrophenol and the ATP-dependent reduction of NAD by succinate catalysed by ox heart submitochondrial particles. Both these effects appear to be due to an inhibition by formaldehyde of the NAD-flavin region of the respiratory chain. 6. Concentrations of dicyclohexylcarbodiimide or tributyltin sufficient to abolish ADP-stimulated respiration blocked the dinitrophenol-stimulated adenosine triphosphatase activity, whereas mersalyl and formaldehyde caused only partial inhibition of ATP hydrolysis. 7. When mitochondria were incubated with dinitrophenol and ATP, less than 10% of the total inorganic phosphate liberated was recovered in the mitochondria and no swelling occurred. In the presence of mersalyl or formaldehyde at least 80% of the total inorganic phosphate liberated was retained in the mitochondria and extensive swelling was observed. This swelling was inhibited by oligomycin but not by antimycin or rotenone. 8. The addition of mersalyl to mitochondria swollen by treatment with

  11. Removal and recovery of phosphate from water by calcium-silicate composites-novel adsorbents made from waste glass and shells.

    Science.gov (United States)

    Jiang, Dan; Amano, Yoshimasa; Machida, Motoi

    2017-03-01

    The removal and recovery of phosphate from water by calcium-silicate composite (CSC) and alkali-treated calcium-silicate composite (ASC) was investigated. ASC had a higher specific surface area and total pore volume, and exhibited better performance of phosphate adsorption than CSC. In the batch mode adsorption studies, the isotherm adsorption experiments data fitted well the Langmuir isotherm model and the maximum adsorption capacities were 120 and 73.0 mg/g for ASC and for CSC, respectively. For the kinetic study, the experimental data fitted very well the pseudo-second-order kinetic model. The uptake of phosphate could be performed well over a wide pH range, from 3.0 to 13.0 for ASC and from 4.0 to 13.0 for CSC. The adsorption of phosphate by ASC was very selective even with 10 times higher concentration of other coexistent anions. For the adsorption of low phosphate concentration (10 mg/L), ASC could efficiently remove phosphate at the dosage of 0.8 g/L, while CSC was even difficult to remove phosphate at the dosage of 4.0 g/L. Phosphate fractionation results and FTIR spectra showed that phosphate-Ca complex was formed through phosphate adsorption process. The adsorbed phosphate could be successfully desorbed by 2% citric acid solution, indicating that the adsorbent after adsorbed phosphate could be reusable as fertilizer in the agricultural field.

  12. Phosphate: are we squandering a scarce commodity?

    Science.gov (United States)

    Ferro, Charles J; Ritz, Eberhard; Townend, Jonathan N

    2015-02-01

    Phosphorus is an essential element for life but is a rare element in the universe. On Earth, it occurs mostly in the form of phosphates that are widespread but predominantly at very low concentration. This relative rarity has resulted in a survival advantage, in evolutionary terms, to organisms that conserve phosphate. When phosphate is made available in excess it becomes a cause for disease, perhaps best recognized as a potential cardiovascular and renal risk factor. As a reaction to the emerging public health issue caused by phosphate additives to food items, there have been calls for a public education programme and regulation to bring about a reduction of phosphate additives to food. During the Paleoproterzoic era, an increase in the bioavailability of phosphate is thought to have contributed significantly to the oxygenation of our atmosphere and a dramatic increase in the evolution of new species. Currently, phosphate is used poorly and often wasted with phosphate fertilizers washing this scarce commodity into water bodies causing eutrophication and algal blooms. Ironically, this is leading to the extinction of hundreds of species. The unchecked exploitation of phosphate rock, which is an increasingly rare natural resource, and our dependence on it for agriculture may lead to a strange situation in which phosphate might become a commodity to be fought over whilst at the same time, health and environmental experts are likely to recommend reductions in its use. © The Author 2014. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

  13. The role of phosphate in kidney disease.

    Science.gov (United States)

    Vervloet, Marc G; Sezer, Siren; Massy, Ziad A; Johansson, Lina; Cozzolino, Mario; Fouque, Denis

    2017-01-01

    The importance of phosphate homeostasis in chronic kidney disease (CKD) has been recognized for decades, but novel insights - which are frequently relevant to everyday clinical practice - continue to emerge. Epidemiological data consistently indicate an association between hyperphosphataemia and poor clinical outcomes. Moreover, compelling evidence suggests direct toxicity of increased phosphate concentrations. Importantly, serum phosphate concentration has a circadian rhythm that must be considered when interpreting patient phosphate levels. Detailed understanding of dietary sources of phosphate, including food additives, can enable phosphate restriction without risking protein malnutrition. Dietary counselling provides an often underestimated opportunity to target the increasing exposure to dietary phosphate of both the general population and patients with CKD. In patients with secondary hyperparathyroidism, bone can be an important source of serum phosphate, and adequate appreciation of this fact should impact treatment. Dietary and pharmotherapeutic interventions are efficacious strategies to lower phosphate intake and serum concentration. However, strong evidence that targeting serum phosphate improves patient outcomes is currently lacking. Future studies are, therefore, required to investigate the effects of modern dietary and pharmacological interventions on clinically meaningful end points.

  14. The Use of Rock Phosphate and Phosphate Solubilising Fungi ...

    African Journals Online (AJOL)

    0 kg/ha P2O5, 40 kg/ha P2O5 RP, 80 kg/ha P2O5 RP, 120 kg/ha P2O5 RP and 45 kg/ha P2O5-triple super phosphate (TSP), while the planting dates of pigeon pea was set up as subplot (40 DAS –pigeon pea planted 40 days after sowing rice seed and 80 DAS- pigeon pea planted 80 days after sowing rice). In the second ...

  15. Interaction between Lubricants Containing Phosphate Ester Additives and Stainless Steels

    Directory of Open Access Journals (Sweden)

    David W. Johnson

    2013-05-01

    Full Text Available One way to improve fuel efficiency in today’s jet aircraft engines is to create an environment for higher operating temperatures and speeds. New and improved lubricants and bearing materials must be developed to remain stable in these elevated operating temperatures. Three lubricants, with varying amounts of tricresyl phosphate added as an anti-wear/extreme pressure additive were tested on two different stainless steels at varying temperatures ranging from 300 °C to 350 °C in vacuum. Significant decomposition of the lubricant base-stocks and the phosphate ester additive did occur in most of the trials resulting in the formation of carboxylic acids and phenols. In these cases a film containing phosphorus was deposited onto the stainless steel substrate.

  16. Inorganic phosphate blocks binding of pre-miRNA to Dicer-2 via its PAZ domain

    Science.gov (United States)

    Fukunaga, Ryuya; Colpan, Cansu; Han, Bo W; Zamore, Phillip D

    2014-01-01

    In Drosophila, Dicer-1 produces microRNAs (miRNAs) from pre-miRNAs, whereas Dicer-2 generates small interfering RNAs from long double-stranded RNA (dsRNA), a process that requires ATP hydrolysis. We previously showed that inorganic phosphate inhibits Dicer-2 cleavage of pre-miRNAs, but not long dsRNAs. Here, we report that phosphate-dependent substrate discrimination by Dicer-2 reflects dsRNA substrate length. Efficient processing by Dicer-2 of short dsRNA requires a 5′ terminal phosphate and a two-nucleotide, 3′ overhang, but does not require ATP. Phosphate inhibits cleavage of such short substrates. In contrast, cleavage of longer dsRNA requires ATP but no specific end structure: phosphate does not inhibit cleavage of these substrates. Mutation of a pair of conserved arginine residues in the Dicer-2 PAZ domain blocked cleavage of short, but not long, dsRNA. We propose that inorganic phosphate occupies a PAZ domain pocket required to bind the 5′ terminal phosphate of short substrates, blocking their use and restricting pre-miRNA processing in flies to Dicer-1. Our study helps explain how a small molecule can alter the substrate specificity of a nucleic acid processing enzyme. PMID:24488111

  17. Hydrogen production by electrolysis of a phosphate solution on a stainless steel cathode

    Energy Technology Data Exchange (ETDEWEB)

    De Silva Munoz, Leonardo; Bergel, Alain; Basseguy, Regine [Laboratoire de Genie Chimique (CNRS-Universite de Toulouse), 4 allee Emile Monso, 31432 Toulouse cedex 4 (France); Feron, Damien [Service de la Corrosion et du Comportement des Materiaux dans leur Environnement, CEA-Saclay, 91191 GIF-SUR-YVETTE Cedex (France)

    2010-08-15

    The catalytic properties of phosphate species, already shown on the reduction reaction in anaerobic corrosion of steels, are exploited here for hydrogen production. Phosphate species work as a homogeneous catalyst that enhances the cathodic current at mild pH values. A voltammetric study of the hydrogen evolution reaction is performed using phosphate solutions at different concentrations on 316L stainless steel and platinum rotating disk electrodes. Then, hydrogen is produced in an electrolytic cell using a phosphate solution as the catholyte. Results show that 316L stainless steel electrodes have a stable behaviour as cathodes in the electrolysis of phosphate solutions. Phosphate (1 M, pH 4.0/5.0) as the catholyte can equal the performance of a KOH 25%w solution with the advantage of working at mild pH values. The use of phosphate and other weak acids as catalysts of the hydrogen evolution reaction could be a promising technology in the development of electrolysis units that work at mild pH values with low-cost electrodes and construction materials. (author)

  18. System-Wide Adaptations of Desulfovibrio alaskensis G20 to Phosphate-Limited Conditions.

    Directory of Open Access Journals (Sweden)

    Tanja Bosak

    Full Text Available The prevalence of lipids devoid of phosphorus suggests that the availability of phosphorus limits microbial growth and activity in many anoxic, stratified environments. To better understand the response of anaerobic bacteria to phosphate limitation and starvation, this study combines microscopic and lipid analyses with the measurements of fitness of pooled barcoded transposon mutants of the model sulfate reducing bacterium Desulfovibrio alaskensis G20. Phosphate-limited G20 has lower growth rates and replaces more than 90% of its membrane phospholipids by a mixture of monoglycosyl diacylglycerol (MGDG, glycuronic acid diacylglycerol (GADG and ornithine lipids, lacks polyphosphate granules, and synthesizes other cellular inclusions. Analyses of pooled and individual mutants reveal the importance of the high-affinity phosphate transport system (the Pst system, PhoR, and glycolipid and ornithine lipid synthases during phosphate limitation. The phosphate-dependent synthesis of MGDG in G20 and the widespread occurrence of the MGDG/GADG synthase among sulfate reducing ∂-Proteobacteria implicate these microbes in the production of abundant MGDG in anaerobic environments where the concentrations of phosphate are lower than 10 μM. Numerous predicted changes in the composition of the cell envelope and systems involved in transport, maintenance of cytoplasmic redox potential, central metabolism and regulatory pathways also suggest an impact of phosphate limitation on the susceptibility of sulfate reducing bacteria to other anthropogenic or environmental stresses.

  19. Phosphate solubilizing ability of Emericella nidulans strain V1 isolated from vermicompost.

    Science.gov (United States)

    Bhattacharya, Satya Sunder; Barman, Soma; Ghosh, Ranjan; Duary, Raj Kumar; Goswami, Linee; Mandal, Narayan C

    2013-10-01

    Phosphorus is one of the key factors that regulate soil fertility. Its deficiencies in soil are largely replenished by chemical fertilizers. The present study was aimed to isolate efficient phosphate solubilizing fungal strains from Eisenia fetida vermicompost. Out of total 30 fungal strains the most efficient phosphate solubilizing one was Emericella (Aspergillus) nidulans V1 (MTCC 11044), identified by custom sequencing of beta-tubulin gene and BLAST analysis. This strain solubilized 13 to 36% phosphate from four different rock phosphates. After three days of incubation of isolated culture with black Mussorie phosphate rock, the highest percentage of phosphate solubilization was 35.5 +/- 1.01 with a pH drop of 4.2 +/- 0.09. Kinetics of solubilization and acid production showed a linear relationship until day five of incubation. Interestingly, from zero to tenth day of incubation, solubility of soil phosphate increased gradually from 4.31 +/- 1.57 to 13.65 +/- 1.82 (mg kg(-1)) recording a maximum of 21.23 +/- 0.54 on day 45 in respect of the V1 isolate. Further, enhanced phosphorus uptake by Phaseolus plants with significant pod yield due to soil inoculation of Emericella nidulans V1 (MTCC 11044), demonstrated its prospect as an effective biofertilizer for plant growth.

  20. Phosphate adsorption performance of a novel filter substrate made from drinking water treatment residuals.

    Science.gov (United States)

    Wang, Wendong; Ma, Cui; Zhang, Yinting; Yang, Shengjiong; Shao, Yue; Wang, Xiaochang

    2016-07-01

    Phosphate is one of the most predominant pollutants in natural waters. Laboratory experiments were conducted to investigate the phosphate adsorption performance of a (NFS) made from drinking water treatment residuals. The adsorption of phosphate on the NFS fitted well with the Freundlich isotherm and pseudo second-order kinetic models. At pH7.0, the maximum adsorption capacity of 1.03mg/g was achieved at 15°C corresponding to the wastewater temperature in cold months, and increased notably to 1.31mg/g at 35°C. Under both acidic conditions (part of the adsorption sites was consumed) and basic conditions (negative charges formed on the surface of NFS, which led to a static repulsion of PO4(3-) and HPO4(2-)), the adsorption of phosphate was slightly inhibited. Further study showed that part of the adsorption sites could be recovered by 0.25mol/L NaOH. The activation energy was calculated to be above 8.0kJ/mol, indicating that the adsorption of phosphate on NFS was probably a chemical process. Considering the strong phosphate adsorption capacity and recoverability, NFS showed great promise on enhancing phosphate removal from the secondary treated wastewater in the filtration process. Copyright © 2016. Published by Elsevier B.V.

  1. phosphates

    Indian Academy of Sciences (India)

    Administrator

    19–21. The degradation of organ- ics is important, especially in the treatment of wastewater from industries. Of the many processes that are known for the degradation of organics, the wet air oxidation (WAO) and advanced oxidation processes (AOP) using Fenton's reagent and photo- chemical reactions in the presence of ...

  2. Can Phosphate Salts Recovered from Manure Replace Conventional Phosphate Fertilizer?

    Directory of Open Access Journals (Sweden)

    Andrea Ehmann

    2017-01-01

    Full Text Available Pig farming produces more manure than can reasonably be spread onto surrounding fields, particularly in regions with high livestock densities and limited land availability. Nutrient recycling offers an attractive solution for dealing with manure excesses and is one main objective of the European commission-funded project “BioEcoSIM”. Phosphate salts (“P-Salt” were recovered from the separated liquid manure fraction. The solid fraction was dried and carbonized to biochar. This study compared the fertilizing performance of P-Salt and conventional phosphate fertilizer and determined whether additional biochar application further increased biomass yields. The fertilizers and biochar were tested in pot experiments with spring barley and faba beans using two nutrient-poor soils. The crops were fertilized with P-Salt at three levels and biochar in two concentrations. Biomass yield was determined after six weeks. Plant and soil samples were analysed for nitrogen, phosphorus and potassium contents. The P-Salt had similar or even better effects than mineral fertilizer on growth in both crops and soils. Slow release of nutrients can prevent leaching, rendering P-Salt a particularly suitable fertilizer for light sandy soils. Biochar can enhance its fertilizing effect, but the underlying mechanisms need further investigation. These novel products are concluded to be promising candidates for efficient fertilization strategies.

  3. Application of Calcium Phosphate Materials in Dentistry

    Directory of Open Access Journals (Sweden)

    Jabr S. Al-Sanabani

    2013-01-01

    Full Text Available Calcium phosphate materials are similar to bone in composition and in having bioactive and osteoconductive properties. Calcium phosphate materials in different forms, as cements, composites, and coatings, are used in many medical and dental applications. This paper reviews the applications of these materials in dentistry. It presents a brief history, dental applications, and methods for improving their mechanical properties. Notable research is highlighted regarding (1 application of calcium phosphate into various fields in dentistry; (2 improving mechanical properties of calcium phosphate; (3 biomimetic process and functionally graded materials. This paper deals with most common types of the calcium phosphate materials such as hydroxyapatite and tricalcium phosphate which are currently used in dental and medical fields.

  4. The effect of environmental conditions and soil physicochemistry on phosphate stabilisation of Pb in shooting range soils.

    Science.gov (United States)

    Sanderson, Peter; Naidu, Ravi; Bolan, Nanthi

    2016-04-01

    The stabilisation of Pb in the soil by phosphate is influenced by environmental conditions and physicochemical properties of the soils to which it is applied. Stabilisation of Pb by phosphate was examined in four soils under different environmental conditions. The effect of soil moisture and temperature on stabilisation of Pb by phosphate was examined by measurement of water extractable and bioaccessible Pb, sequential fractionation and X-ray absorption spectroscopy. The addition of humic acid, ammonium nitrate and chloride was also examined for inhibition or improvement of Pb stability with phosphate treatment. The effect of moisture level varied between soils. In soil MB and DA a soil moisture level of 50% water holding capacity was sufficient to maximise stabilisation of Pb, but in soil TV and PE reduction in bioaccessible Pb was inhibited at this moisture level. Providing moisture at twice the soil water holding capacity did not enhance the effect of phosphate on Pb stabilisation. The difference of Pb stability as a result of incubating phosphate treated soils at 18 °C and 37 °C was relatively small. However wet-dry cycles decreased the effectiveness of phosphate treatment. The reduction in bioaccessible Pb obtained was between 20 and 40% with the most optimal treatment conditions. The reduction in water extractable Pb by phosphate was substantial regardless of incubation conditions and the effect of different temperature and soil moisture regimes was not significant. Selective sequential extraction showed phosphate treatment converted Pb in fraction 1 (exchangeable, acid and water soluble) to fraction 2 (reducible). There were small difference in fraction 4 (residual) Pb and fraction 1 as a result of treatment conditions. X-ray absorption spectroscopy of stabilised PE soil revealed small differences in Pb speciation under varying soil moisture and temperature treatments. The addition of humic acid and chloride produced the greatest effect on Pb speciation in

  5. Phosphate-bonded ceramics as candidate final-waste-form materials

    Energy Technology Data Exchange (ETDEWEB)

    Singh, D.; Wagh, A.S.; Cunnane, J.; Sutaria, M.; Kurokawa, S. [Argonne National Lab., IL (United States); Mayberry, J. [Science Applications International Corp., Idaho Falls, ID (United States)

    1994-12-31

    Room-temperature-setting phosphate-bonded ceramics were studied as candidate materials for stabilizing DOE low-level problem mixed wastes, which cannot be treated by other established stabilization techniques. Phosphates of Mg, Mg-Na, Al, and Zr were studied to stabilize ash-surrogate waste that contained RCRA metals as nitrates and RCRA organics. We show that for a typical loading of 35 wt.% of ash waste, the phosphate ceramics pass the Toxic Chemicals Leaching Procedure test (TCLP). The waste forms have high compression strength that exceeds ASTM recommendations for final waste forms. Detailed X-ray diffraction studies and differential thermal analyses of the waste forms show evidence of chemical reaction of the waste with phosphoric acid and the host matrix. SEM studies show evidence of physical bonding. Excellent performance in the leaching test is attributed to chemical solidification and to both physical and chemical bonding of the ash wastes with the phosphate ceramics.

  6. 1-deoxy-D-xylulose-5-phosphate reductoisomerases, and methods of use

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, Rodney B. (Pullman, WA); Lange, Bernd M. (Pullman, WA)

    2002-07-16

    The present invention relates to isolated DNA sequences which code for the expression of plant 1-deoxy-D-xylulose-5-phosphate reductoisomerase protein, such as the sequence presented in SEQ ID NO:1 which encodes a 1-deoxy-D-xylulose-5-phosphate reductoisomerase protein from peppermint (Mentha x piperita). Additionally, the present invention relates to isolated plant 1-deoxy-D-xylulose-5-phosphate reductoisomerase protein. In other aspects, the present invention is directed to replicable recombinant cloning vehicles comprising a nucleic acid sequence which codes for a plant 1-deoxy-D-xylulose-5-phosphate reductoisomerase, to modified host cells transformed, transfected, infected and/or injected with a recombinant cloning vehicle and/or DNA sequence of the invention.

  7. 1-deoxy-d-xylulose-5-phosphate reductoisomerases and method of use

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, Rodney B. (Pullman, WA); Lange, Bernd M. (Pullman, WA)

    2001-01-01

    The present invention relates to isolated DNA sequences which code for the expression of plant 1-deoxy-D-xylulose-5-phosphate reductoisomerase protein, such as the sequence presented in SEQ ID NO:1 which encodes a 1-deoxy-D-xylulose-5-phosphate reductoisomerase protein from peppermint (Mentha x piperita). Additionally, the present invention relates to isolated plant 1-deoxy-D-xylulose-5-phosphate reductoisomerase protein. In other aspects, the present invention is directed to replicable recombinant cloning vehicles comprising a nucleic acid sequence which codes for a plant 1-deoxy-D-xylulose-5-phosphate reductoisomerase, to modified host cells transformed, transfected, infected and/or injected with a recombinant cloning vehicle and/or DNA sequence of the invention.

  8. Advanced Polyelectrolyte-Modified Zinc Phosphate Coatings

    Science.gov (United States)

    1995-09-01

    September 1995 4. TITLE AND SUBTITLE Advanced Polyelectrolyte-Modified Zinc Phosphate Coatings 6. AUTHOR(S) T. Sugama, N. Carciello and C.I...was to develop polyelectrolyte-modified zinc phosphate conversion coatings to protect cold-rolled steels against corrosion. Accordingly, we formulated...environmentally acceptable material systems for the zinc phosphating make-up solution, and developed the process technology to meet this purpose

  9. Phosphate Glass Gamma-Radiation Dosimeter

    Science.gov (United States)

    1952-11-30

    categories of items« .dosed dosimeters* unmounted squares of dosed silver phosphate glass, lype 1S-10U standards (containing manganese and pyrex glass...8217- •naaw "?r t’OLAnOID CORPORATION --nnSEÄUCH DEPARTMENT £| RESTRICTED Final Report on Phosphate Glass Qsasoa*4Radlation Dosimeter tJnder...dosimeters Relation to ether contracts Contract dates, amendments, etc« Previous reports Technical personnel Properties of Silver Phosphate

  10. How versatile are inositol phosphate kinases?

    OpenAIRE

    Shears, Stephen B.

    2004-01-01

    This review assesses the extent and the significance of catalytic versatility shown by several inositol phosphate kinases: the inositol phosphate multikinase, the reversible Ins(1,3,4) P (3)/Ins(3,4,5,6) P (4) kinase, and the kinases that synthesize diphosphoinositol polyphosphates. Particular emphasis is placed upon data that are relevant to the situation in vivo. It will be shown that catalytic promiscuity towards different inositol phosphates is not typically an evolutionary compromise, bu...

  11. Structure of the lipoteichoic acids from Bifidobacterium bifidum spp. pennsylvanicum

    NARCIS (Netherlands)

    Halbeek, H. van; Camp, H.J.M. op den; Veerkamp, J.H.; Oosterhof, A.

    1984-01-01

    The lipoteichoic acids from Bifidobucterium bifidum spp. pennsylvanicum were extracted from cytoplasmic membranes or from disintegrated bacteria with aqueous phenol and purified by gel chromatography. The lipoteichoic acid preparations contained phosphate, glycerol, galactose, glucose and fatty

  12. Lack of awareness among future medical professionals about the risk of consuming hidden phosphate-containing processed food and drinks.

    Directory of Open Access Journals (Sweden)

    Yoshiko Shutto

    Full Text Available Phosphate toxicity is an important determinant of mortality in patients with chronic kidney disease (CKD, particularly those undergoing hemodialysis treatments. CKD patients are advised to take a low phosphate-containing diet, and are additionally prescribed with phosphate-lowering drugs. Since these patients usually seek guidance from their physicians and nurses for their dietary options, we conducted a survey to determine the levels of awareness regarding the high phosphate content in commercially processed food and drinks among medical and nursing students at the Hirosaki University School of Medicine in Japan. For this survey, 190 medical and nursing students (average age 21.7±3 years were randomly selected, and provided with a list of questions aimed at evaluating their awareness of food and drinks containing artificially added phosphate ingredients. While 98.9% of these students were aware of the presence of sugar in commercially available soda drinks, only 6.9% were aware of the presence of phosphate (phosphoric acid. Similarly, only 11.6% of these students were aware of the presence of phosphate in commercially processed food, such as hamburgers and pizza. Moreover, around two thirds of the surveyed students (67.7% were unaware of the harmful effects of unrestricted consumption of phosphate-containing food and drinks. About 28% of the surveyed students consume such "fast food" once a week, while 40% drink at least 1∼5 cans of soda drinks/week. After realizing the potential long-term risks of consuming excessive phosphate-containing food and drinks, 40.5% of the survey participants considered reducing their phosphate intake by minimizing the consumption of commercially processed "fast food" items and soda drinks. Moreover, another 48.4% of students showed interest in obtaining more information on the negative health effects of consuming excessive amounts of phosphate. This survey emphasizes the need for educational initiative to raise

  13. Inducing mineral precipitation in groundwater by addition of phosphate

    Directory of Open Access Journals (Sweden)

    Hartmann Thomas

    2011-10-01

    Full Text Available Abstract Background Induced precipitation of phosphate minerals to scavenge trace elements from groundwater is a potential remediation approach for contaminated aquifers. The success of engineered precipitation schemes depends on the particular phases generated, their rates of formation, and their long term stability. The purpose of this study was to examine the precipitation of calcium phosphate minerals under conditions representative of a natural groundwater. Because microorganisms are present in groundwater, and because some proposed schemes for phosphate mineral precipitation rely on stimulation of native microbial populations, we also tested the effect of bacterial cells (initial densities of 105 and 107 mL-1 added to the precipitation medium. In addition, we tested the effect of a trace mixture of propionic, isovaleric, formic and butyric acids (total concentration 0.035 mM. Results The general progression of mineral precipitation was similar under all of the study conditions, with initial formation of amorphous calcium phosphate, and transformation to poorly crystalline hydroxylapatite (HAP within one week. The presence of the bacterial cells appeared to delay precipitation, although by the end of the experiments the overall extent of precipitation was similar for all treatments. The stoichiometry of the final precipitates as well as Rietveld structure refinement using x-ray diffraction data indicated that the presence of organic acids and bacterial cells resulted in an increasing a and decreasing c lattice parameter, with the higher concentration of cells resulting in the greatest distortion. Uptake of Sr into the solids was decreased in the treatments with cells and organic acids, compared to the control. Conclusions Our results suggest that the minerals formed initially during an engineered precipitation application for trace element sequestration may not be the ones that control long-term immobilization of the contaminants. In

  14. Study of Viability of Phosphate Solubilizing Bacteria in Phosphate granules

    Directory of Open Access Journals (Sweden)

    hajar rajabi

    2017-06-01

    Full Text Available Introduction: sustainable development and the environment are interconnected. Sustainable agriculture is continuous utilization of a farm with respect to various aspects of environmental conditions by using fewer inputs (other than Bio-fertilizers. Phosphorus is one of the essential elements for the plants. Management of soil is possible by using biological fertilizers pillar of sustainable agriculture and providing some of the phosphorus needed by plants via bio-fertilizers. Phosphorus deficiency is extremely effective on the plant growth and productivity. The application of phosphorus fertilizers is expensive and dangerous. In addition, phosphorus in the soilmay become insoluble and will be unavailable to the plants. Studies showed that phosphate solubilizing bacteria in the soil rhizosphere are active and by root exudates solve insoluble phosphates such as tricalcium phosphate, and form absorbable P for plant. Consequently, the use of microbial fertilizers could reduce excessive use of chemical fertilizers and lead to decrease their harmful effects and protect the environment and conservation of available resources. The biological phosphate fertilizer industry uses sugar beet molasses as a binder and drying granules at high temperatures. Therefore, it is important to evaluate the durability of the bacteria in molasses at high temperature. Materials and Methods: This study was designed as completely randomized design in a factorial arrangement.10 isolates were selected and the ratios of 50%, 25%, 15% and 10% of the apatite, organic matter, sulfur and soluble granule (ratio 1: 1 and 2: 1 bacteria and molasses, respectively, for each isolate was prepared. The final product was dried at 28 and 40 °C and remained for 4 months and population counted at first day and 10, 20, 30, 60, 90 and 120 days after the preparing. The population was counted by the serial dilution technique and cultured at Sperber media. Results and Discussion:Comparing the

  15. Biomineralization of U(VI) phosphate promoted by microbially-mediated phytate hydrolysis in contaminated soils

    Science.gov (United States)

    Salome, Kathleen R.; Beazley, Melanie J.; Webb, Samuel M.; Sobecky, Patricia A.; Taillefert, Martial

    2017-01-01

    The bioreduction of uranium may immobilize a significant fraction of this toxic contaminant in reduced environments at circumneutral pH. In oxic and low pH environments, however, the low solubility of U(VI)-phosphate minerals also makes them good candidates for the immobilization of U(VI) in the solid phase. As inorganic phosphate is generally scarce in soils, the biomineralization of U(VI)-phosphate minerals via microbially-mediated organophosphate hydrolysis may represent the main immobilization process of uranium in these environments. In this study, contaminated sediments were incubated aerobically in two pH conditions to examine whether phytate, a naturally-occurring and abundant organophosphate in soils, could represent a potential phosphorous source to promote U(VI)-phosphate biomineralization by natural microbial communities. While phytate hydrolysis was not evident at pH 7.0, nearly complete hydrolysis was observed both with and without electron donor at pH 5.5, suggesting indigenous microorganisms express acidic phytases in these sediments. While the rate of hydrolysis of phytate generally increased in the presence of uranium, the net rate of inorganic phosphate production in solution was decreased and inositol phosphate intermediates were generated in contrast to similar incubations conducted without uranium. These findings suggest uranium stress enhanced the phytate-metabolism of the microbial community, while simultaneously inhibiting phosphatase production and/or activity by the indigenous population. Finally, phytate hydrolysis drastically decreased uranium solubility, likely due to formation of ternary sorption complexes, U(VI)-phytate precipitates, and U(VI)-phosphate minerals. Overall, the results of this study provide evidence for the ability of natural microbial communities to liberate phosphate from phytate in acidic sediments, possibly as a detoxification mechanism, and demonstrate the potential utility of phytate-promoted uranium

  16. A weak-base fibrous anion exchanger effective for rapid phosphate removal from water.

    Science.gov (United States)

    Awual, Md Rabiul; Jyo, Akinori; El-Safty, Sherif A; Tamada, Masao; Seko, Noriaki

    2011-04-15

    This work investigated that weak-base anion exchange fibers named FVA-c and FVA-f were selectively and rapidly taken up phosphate from water. The chemical structure of both FVA-c and FVA-f was the same; i.e., poly(vinylamine) chains grafted onto polyethylene coated polypropylene fibers. Batch study using FVA-c clarified that this preferred phosphate to chloride, nitrate and sulfate in neutral pH region and an equilibrium capacity of FVA-c for phosphate was from 2.45 to 6.87 mmol/g. Column study using FVA-f made it clear that breakthrough capacities of FVA-f were not strongly affected by flow rates from 150 to 2000 h(-1) as well as phosphate feed concentration from 0.072 to 1.6mM. Under these conditions, breakthrough capacities were from 0.84 to 1.43 mmol/g indicating high kinetic performances. Trace concentration of phosphate was also removed from feeds containing 0.021 and 0.035 mM of phosphate at high feed flow rate of 2500 h(-1), breakthrough capacities were 0.676 and 0.741 mmol/g, respectively. The column study also clarified that chloride and sulfate did not strongly interfere with phosphate uptake even in their presence of equimolar and fivefold molar levels. Adsorbed phosphate on FVA-f was quantitatively eluted with 1M HCl acid and regenerated into hydrochloride form simultaneously for next phosphate adsorption operation. Therefore, FVA-f is able to use long time even under rigorous chemical treatment of multiple regeneration/reuse cycles without any noticeable deterioration. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Phosphate stabilization of flue gas ashes from waste incineration; Fosfatstabilisering av roekgasaska fraan avfallsfoerbraenning

    Energy Technology Data Exchange (ETDEWEB)

    Kullberg, S. [Geodesign AB, Linkoeping (Sweden)

    1995-05-01

    This study deals with the immobilization of heavy metals and other elements in flue gas ashes from household waste incineration by the addition of phosphates to the ash. It also describes the FUDD-technique (FUnction-adapted Design and Deposition) for deposition of the stabilized ash. In this work, phosphates obtained from phosphoric acid have been added to ash in proportions of 2.8% and 3.7% by weight of ash. Phosphates have also been injected into the flue gases, in this case with proportions of 4.7% and 16.3%. The samples have been studied both in the field and in the laboratory in regard to compaction properties, permeability, chemical solid phase content, HCl in the flue gases, leaching of metals via batch tests, availability tests and column tests. In batch tests, the stabilized samples show an immobilization of most metals except cadmium. Lead has been reduced by 97.0-99.9%. Cadmium has been mobilized by a factor of 2-30 in this experiment. The best results are obtained with addition of phosphates to the flue gases. In the availability tests, with addition of phosphates to flue gases, all environmentally destructive metals except arsenic and nickel have been immobilized to varying degree. The reduction is greatest for lead, aluminium, copper, mercury and zinc. With the addition of phosphates to ash, aluminium, copper and lead have been immobilized. In opposite, arsenic, cobalt and nickel were mobilized. The addition of 4-5% phosphates in the flue gas reactor produced only a marginal effect on the HCl concentration in the flue gases. The use of phosphates increases the HF concentration by about 3 mg/Nm{sup 3}. The cost for phosphate stabilization have been estimated at SEK 110-220 per ton of ash including costs for stabilization equipment. 18 refs, 15 figs, 13 tabs

  18. Genome-wide characterization of the phosphate starvation response in Schizosaccharomyces pombe.

    Science.gov (United States)

    Carter-O'Connell, Ian; Peel, Michael T; Wykoff, Dennis D; O'Shea, Erin K

    2012-12-12

    Inorganic phosphate is an essential nutrient required by organisms for growth. During phosphate starvation, Saccharomyces cerevisiae activates the phosphate signal transduction (PHO) pathway, leading to expression of the secreted acid phosphatase, PHO5. The fission yeast, Schizosaccharomyces pombe, regulates expression of the ScPHO5 homolog (pho1+) via a non-orthologous PHO pathway involving genetically identified positive (pho7+) and negative (csk1+) regulators. The genes induced by phosphate limitation and the molecular mechanism by which pho7+ and csk1+ function are unknown. Here we use a combination of molecular biology, expression microarrays, and chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-Seq) to characterize the role of pho7+ and csk1+ in the PHO response. We define the set of genes that comprise the initial response to phosphate starvation in S. pombe. We identify a conserved PHO response that contains the ScPHO5 (pho1+), ScPHO84 (SPBC8E4.01c), and ScGIT1 (SPBC1271.09) orthologs. We identify members of the Pho7 regulon and characterize Pho7 binding in response to phosphate-limitation and Csk1 activity. We demonstrate that activation of pho1+ requires Pho7 binding to a UAS in the pho1+ promoter and that Csk1 repression does not regulate Pho7 enrichment. Further, we find that Pho7-dependent activation is not limited to phosphate-starvation, as additional environmental stress response pathways require pho7+ for maximal induction. We provide a global analysis of the transcriptional response to phosphate limitation in S. pombe. Our results elucidate the conserved core regulon induced in response to phosphate starvation in this ascomycete distantly related to S. cerevisiae and provide a better understanding of flexibility in environmental stress response networks.

  19. Phosphate functional groups improve OPF osteoconduction and BMP-2 osteoinductive efficacy.

    Science.gov (United States)

    Olthof, Maurits Geert Laurent; Tryfonidou, M; Liu, Xifeng; Pouran, Behdad; Meij, Björn; Dhert, Wouter; Yaszemski, Michael J; Lu, Lichun; Alblas, Jacqueline; Kempen, Diederik H R

    2017-10-25

    Off the shelf availability in large quantities, drug delivery functionality, and modifiable chemistry and mechanical properties makes synthetic polymers highly suitable candidates for bone grafting. However, most synthetic polymers lack the ability to support cell attachment, proliferation, migration and differentiation and ultimately tissue formation. Incorporating anionic peptides into the polymer that mimic acidic proteins, which contribute to biomineralization and cellular attachment, could enhance bone formation. Therefore, this study investigates the effect of a phosphate functional group on osteoconductivity and BMP-2 induced bone formation in an injectable and biodegradable oligo[(polyethylene glycol) fumarate] (OPF) hydrogel. Three types of OPF hydrogels were fabricated using 0%, 20% or 40% Bis(2-(methacryloyloxy)ethyl) phosphate (BP) creating unmodified OPF-noBP and phosphate modified OPF-BP20 and OPF-BP40, respectively. To account for the osteoinductive effect of various BMP-2 release profiles, two different release profiles (i.e. different ratios of burst and sustained release) were obtained by varying the BMP-2 loading method. To investigate the osteoconductive effect of phosphate modification, unloaded OPF composites were assessed for bone formation in a bone defect model after 3, 6 and 9 weeks. To determine the effect of the hydrogel phosphate modification on BMP-2 induced bone formation, BMP-2 loaded OPF composites with differential BMP-2 release were analyzed after 9 weeks of subcutaneous implantation in rats. The phosphate modified OPF hydrogels (OPF-BP20, OPF-BP40) generated significantly more bone in an orthotopic defect compared to the unmodified hydrogel (OPF-noBP). Furthermore, the phosphate functionalized surface enhanced BMP-2 induced ectopic bone formation regardless of the BMP-2 release profile. In conclusion, this study clearly shows that phosphate functional groups improve the osteoconductive properties of OPF and enhanced BMP-2 induced

  20. Mineral phosphate solubilizing bacterial community in agro-ecosystem

    African Journals Online (AJOL)

    Four insoluble phosphate sources; purulia rock phosphate (PRP), mussourie rock phosphate (MRP), crystalline iron and aluminum phosphate were charged in basic ... On the whole, the community composition of phosphate solubilizing bacteria reduced gradually under the influence of cultivation and fertilization in different ...

  1. Bio-treatment of phosphate from synthetic wastewater using ...

    African Journals Online (AJOL)

    In this study, the efficient phosphate utilizing isolates were used to remove phosphate from synthetic phosphate wastewater was tested using batch scale process. Hence the objective of the present study was to examine the efficiency of bacterial species individually for the removal of phosphate from synthetic phosphate ...

  2. Dicalcium phosphate (CaHPO4·2H2O) precipitation through ortho- or meta-phosphoric acid-etching: effects on the durability and nanoleakage/ultra-morphology of resin-dentine interfaces.

    Science.gov (United States)

    Feitosa, Victor Pinheiro; Bazzocchi, Maria Giulia; Putignano, Angelo; Orsini, Giovanna; Luzi, Arlinda Luzi; Sinhoreti, Mário Alexandre Coelho; Watson, Timothy F; Sauro, Salvatore

    2013-11-01

    To compare the effects of two etching procedures using meta-phosphoric (MPA) or ortho-phosphoric acid (OPA) on dentine demineralisation, resin-dentine bonds durability and interface nanoleakage/ultra-morphology. Middle-dentine specimens were etched using 37% OPA (15s) or 40% MPA (60s) and submitted to infrared spectroscopy (FTIR) or ultra-morphology dye-assisted (calcium-staining) confocal microscopy (Ca-CLSM). A three-step etch-and-rinse adhesive was formulated, applied onto dentine and light-cured for 30s before composite build-up. After 24h, the dentine-bonded specimens were cut into 1mm(2) beams; half were immediately submitted to microtensile bond strength (μTBS) and half stored in DW for six months. The μTBS results were analysed with repeated-measures ANOVA and Tukey's test (pprecipitation in MPA-etched dentine and on the bottom (front of demineralisation) of the OPA-etched dentine. Statistical analysis showed similar μTBS for both etching procedures after 24h. The μTBS of specimens in OPA-group dropped significantly (p0.05). CLSM depicted no evident sign of nanoleakage within the resin-dentine interface of the MPA-treated specimens, while the specimens in OPA-group presented intense nanoleakage and interface degradation. The use of MPA (60s) as an alternative dentine conditioning agent in etch-and-rinse bonding procedures may be a suitable strategy to create more durable resin-dentine bonds. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. [Decrease of phosphate concentration in the medium by Brevibacterium casei cells].

    Science.gov (United States)

    Riazanova, L P; Smirnov, A V; Kulakovskaia, T V; Kulaev, I S

    2007-01-01

    Brevibacteria able to decrease phosphate concentration in the medium are of interest for the study of the role of bacteria in the phosphorus cycle and for development of biotechnology of phosphate removal from waste. Brevibacterium casei, Brevibacterium linens, and Brevibacterium epidermidis grown in media with initial phosphorus concentrations of 1-11 mM were shown to decrease its concentration by 90%. The composition of the incubation medium required for B. casei to carry out this process was established. This process occurs in the absence of glucose but requires the presence of Mg2+, NH4+, and alpha-ketoglutarate. The latter two components may be replaced by amino acids metabolized to NH4+ and alpha-ketoglutarate: histidine, arginine, glutamine, proline, or glutamic acid. No formation of insoluble phosphate salts was observed when the media were incubated under the same conditions with heat-inactivated cells or without cells at pH 7-8.5.

  4. Electrochemical phosphate recovery from nanofiltration concentrates

    NARCIS (Netherlands)

    Kappel, C.; Yasadi, K.; Temmink, B.G.; Metz, S.J.; Kemperman, A.J.B.; Nijmeijer, K.; Zwijnenburg, A.; Witkamp, G.J.; Rijnaarts, H.

    2013-01-01

    The high total phosphorus content of raw domestic wastewater with its significant eutrophication potential offers an excellent possibility for phosphate recovery. Continuous recirculation of NF concentrate to an MBR and simultaneous phosphate recovery from the NF concentrate can be applied to

  5. Sphingosine-1-phosphate and renal vasoconstriction

    DEFF Research Database (Denmark)

    Jensen, Boye L

    2018-01-01

    In the present issue of Acta Physiologica, Guan et al. in their article "Mechanisms of sphingosine-1-phosphate-mediated vasoconstriction of rat afferent arterioles" (1) address the signaling events associated with sphingosine-1-phosphate (S1P)-mediated renal afferent vasoconstriction and show in...

  6. Thermal stability of phosphate coatings on steel

    OpenAIRE

    P. Pokorny; P. Szelag; Novak, M; L. Mastny; Brozek, V.

    2015-01-01

    The work was validated thermal stability of zinc, manganese and tri-cations phosphate coatings on steel, made from commercial phosphating bath type Pragofos. Thermogravimetric data dehydration of scholzite, phosphophylite and hureaulite coatings in the temperature range 160 °C – 400 °C define the conditions for applying paints with higher firing temperature or thermal spraying ceramic coatings.

  7. Thermal stability of phosphate coatings on steel

    Directory of Open Access Journals (Sweden)

    P. Pokorny

    2015-07-01

    Full Text Available The work was validated thermal stability of zinc, manganese and tri-cations phosphate coatings on steel, made from commercial phosphating bath type Pragofos. Thermogravimetric data dehydration of scholzite, phosphophylite and hureaulite coatings in the temperature range 160 °C – 400 °C define the conditions for applying paints with higher firing temperature or thermal spraying ceramic coatings.

  8. Rock phosphate solubilization by the ectomycorrhizal fungus ...

    African Journals Online (AJOL)

    SAM

    2014-06-18

    Jun 18, 2014 ... soils. Key words: Ectomycorrhizal fungi, Laccaria fraterna, mycorrhizal helper bacteria, phosphate solubilization, rock phosphate. INTRODUCTION. Phosphorus (P) is the second major nutrient next to nitrogen required by plants. However, many soils throughout the world are P deficient while nearly 95 to.

  9. Efficient regeneration of NADPH in a 3-enzyme cascade reaction by in situ generation of glucose 6-phosphate from glucose and pyrophosphate

    NARCIS (Netherlands)

    Hartog, A.F.; van Herk, T.; Wever, R.

    2011-01-01

    We report here a promising method to regenerate NADPH (nicotinamide adenine dinucleotide phosphate) using the intermediate formation of glucose 6-phosphate (G6P) from glucose and pyrophosphate (PPi) catalyzed by the acid phosphatase from Shigella flexneri (PhoN-Sf). The G6P formed is used in turn by

  10. Single Step Sintered Calcium Phosphate Fibers from Avian EGG Shell

    Science.gov (United States)

    Dadhich, Prabhash; Das, Bodhisatwa; Dhara, Santanu

    2013-11-01

    Different forms of calcium-phosphate (Hydoxyapatite, α-TCP, β-TCP, CDHA) minerals are found to be major component of bone tissue. Development of calcium-phosphate (CaP) based fibrous microstructures is of significant research interest worldwide owing to its improved mechanical properties and higher interconnectivity. Here we represent a method for single step sintered wet-spun Fibers of calcium phosphate from avian egg shells for biomedical applications. Raw egg shell powder was mixed with chitosan solution and Phosphoric acid. The mixture is milled in a ball mill overnight and then filtered. The slurry was de-aired using 100 microliter 1-octanol per 100 ml of slurry as antifoaming and wet spun in coagulation bath. Fiber was dried overnight and sintered at different temperatures for microstructure and phase analysis. Both green and sintered Fibers were physico-chemical characterized by SEM, EDX, XRD, TGA, DSC, FTIR, and stereo-zoom microscopy. The fibers obtained in this procedure are found to have highly porous interconnected structures which can provide good cell adhesion and therefore can be used for bioactive scaffold making.

  11. Enhanced attenuation of septic system phosphate in noncalcareous sediments.

    Science.gov (United States)

    Robertson, W D

    2003-01-01

    Review of phosphate behavior in four mature septic system plumes on similar textured sand has revealed a strong correlation between carbonate mineral content and phosphate concentrations. A plume on calcareous sand (Cambridge site, 27 wt % CaCO3 equiv.) has proximal zone PO4 concentrations (4.8 mg/L P average) that are about 75% of the septic tank effluent value, whereas three plumes on noncalcareous sand (Muskoka, L. Joseph, and Nobel sites, effluent values. Phosphate attenuation at the noncalcareous sites appears to be an indirect result of the development of acidic conditions (site average pH 3.5 to 5.9) and elevated Al concentrations (up to 24 mg/L), which subsequently causes the precipitation of Al-P minerals such as variscite (AlPO4 x 2H2O). This is supported by scanning electron microscope analyses, which show the widespread occurrence of (Al+P)--rich secondary mineral coatings on sand grains below the infiltration beds. All of these septic systems are more than 10 years old, indicating that these attenuation reactions have substantial longevity. A field lysimeter experiment demonstrated that this reaction sequence can be readily incorporated into engineered waste water treatment systems. We feel this important P removal mechanism has not been adequately recognized, particularly for its potential significance in reducing P loading from septic systems in lakeshore environments.

  12. Metal Phosphate-Supported Pt Catalysts for CO Oxidation

    Directory of Open Access Journals (Sweden)

    Xiaoshuang Qian

    2014-12-01

    Full Text Available Oxides (such as SiO2, TiO2, ZrO2, Al2O3, Fe2O3, CeO2 have often been used to prepare supported Pt catalysts for CO oxidation and other reactions, whereas metal phosphate-supported Pt catalysts for CO oxidation were rarely reported. Metal phosphates are a family of metal salts with high thermal stability and acid-base properties. Hydroxyapatite (Ca10(PO46(OH2, denoted as Ca-P-O here also has rich hydroxyls. Here we report a series of metal phosphate-supported Pt (Pt/M-P-O, M = Mg, Al, Ca, Fe, Co, Zn, La catalysts for CO oxidation. Pt/Ca-P-O shows the highest activity. Relevant characterization was conducted using N2 adsorption-desorption, inductively coupled plasma (ICP atomic emission spectroscopy, X-ray diffraction (XRD, transmission electron microscopy (TEM, CO2 temperature-programmed desorption (CO2-TPD, X-ray photoelectron spectroscopy (XPS, and H2 temperature-programmed reduction (H2-TPR. This work furnishes a new catalyst system for CO oxidation and other possible reactions.

  13. Phosphate-dependent root system architecture responses to salt stress

    KAUST Repository

    Kawa, Dorota

    2016-05-20

    Nutrient availability and salinity of the soil affect growth and development of plant roots. Here, we describe how phosphate availability affects root system architecture (RSA) of Arabidopsis and how phosphate levels modulate responses of the root to salt stress. Phosphate (Pi) starvation reduced main root length and increased the number of lateral roots of Arabidopsis Col-0 seedlings. In combination with salt, low Pi dampened the inhibiting effect of mild salt stress (75mM) on all measured RSA components. At higher NaCl concentrations, the Pi deprivation response prevailed over the salt stress only for lateral root elongation. The Pi deprivation response of lateral roots appeared to be oppositely affected by abscisic acid (ABA) signaling compared to the salt stress response. Natural variation in the response to the combination treatment of salt and Pi starvation within 330 Arabidopsis accessions could be grouped into four response patterns. When exposed to double stress, in general lateral roots prioritized responses to salt, while the effect on main root traits was additive. Interestingly, these patterns were not identical for all accessions studied and multiple strategies to integrate the signals from Pi deprivation and salinity were identified. By Genome Wide Association Mapping (GWAS) 13 genomic loci were identified as putative factors integrating responses to salt stress and Pi starvation. From our experiments, we conclude that Pi starvation interferes with salt responses mainly at the level of lateral roots and that large natural variation exists in the available genetic repertoire of accessions to handle the combination of stresses.

  14. Preparation of omega-functionalized eicosane-phosphate building blocks.

    Science.gov (United States)

    Jablonkai, Istvan; Oroszlan, Peter

    2005-01-01

    New 1,20-substituted eicosanes carrying phosphate headgroups and readily derivatizable thiol, maleimido, and activated carboxylic ester moieties were prepared. The C20-backbone of these molecules was assembled by a halopolycarbon homologation from 1,8-dichlorooctane and 1,6-dibromohexane. 20-Mercapto- and 20-maleimido-icosylphosphates were synthesized via omega-bromo di-t-butyl protected icosylphosphate while 20-phosphonooxy-icosanoic acid N-hydroxysuccinimidoyl ester was prepared via omega-bromo dibenzyl protected icosylphosphate in multistep syntheses. These molecules can serve as model compounds for studying binding and structural organization on different surfaces with potential applications in the fields of biosensors.

  15. Phosphate rock resources of the United States

    Science.gov (United States)

    Cathcart, James Bachelder; Sheldon, Richard Porter; Gulbrandsen, Robert A.

    1984-01-01

    In 1980, the United States produced about 54 million tons of phosphate rock, or about 40 percent of the world's production, of which a substantial amount was exported, both as phosphate rock and as chemical fertilizer. During the last decade, predictions have been made that easily ruinable, low-cost reserves of phosphate rock would be exhausted, and that by the end of this century, instead of being a major exporter of phosphate rock, the United States might become a net importer. Most analysts today, however, think that exports will indeed decline in the next one or two decades, but that resources of phosphate are sufficient to supply domestic needs for a long time into the future. What will happen in the future depends on the actual availability of low-cost phosphate rock reserves in the United States and in the world. A realistic understanding of future phosphate rock reserves is dependent on an accurate assessment, now, of national phosphate rock resources. Many different estimates of resources exist; none of them alike. The detailed analysis of past resource estimates presented in this report indicates that the estimates differ more in what is being estimated than in how much is thought to exist. The phosphate rock resource classification used herein is based on the two fundamental aspects of a mineral resource(l) the degree of certainty of existence and (2) the feasibility of economic recovery. The comparison of past estimates (including all available company data), combined with the writers' personal knowledge, indicates that 17 billion metric tons of identified, recoverable phosphate rock exist in the United States, of which about 7 billion metric tons are thought to be economic or marginally economic. The remaining 10 billion metric tons, mostly in the Northwestern phosphate district of Idaho, are considered to be subeconomic, ruinable when some increase in the price of phosphate occurs. More than 16 billion metric tons probably exist in the southeastern

  16. Calcium phosphate: a substitute for aluminum adjuvants?

    Science.gov (United States)

    Masson, Jean-Daniel; Thibaudon, Michel; Bélec, Laurent; Crépeaux, Guillemette

    2017-03-01

    Calcium phosphate was used as an adjuvant in France in diphtheria, tetanus, pertussis and poliomyelitis vaccines. It was later completely substituted by alum salts in the late 80's, but it still remains as an approved adjuvant for the World Health Organization for human vaccination. Area covered: Thus, calcium phosphate is now considered as one of the substances that could replace alum salts in vaccines. The aim of this paper is to draw a review of existing data on calcium phosphate as an adjuvant in order to bring out the strengths and weaknesses for its use on a large scale. Expert commentary: Calcium phosphate is a compound naturally present in the organism, safe and already used in human vaccination. Beyond comparisons with the other adjuvants, calcium phosphate represents a good candidate to replace or to complete alum salts as a vaccine adjuvant.

  17. Short-term supply of elevated phosphate alters the belowground carbon allocation costs and functions of lupin cluster roots and nodules.

    Science.gov (United States)

    Thuynsma, Rochelle; Valentine, Alex; Kleinert, Aleysia

    2014-05-01

    The legume Lupinus albus is able to survive under low nutrient conditions due to the presence of two specialized below ground organs for the acquisition of nitrogen and phosphate, respectively.In this regard, cluster roots increase phosphate uptake and root nodules acquire atmospheric N₂via biological nitrogen fixation(BNF). Although these organs normally tolerate low phosphate conditions, very little is known about their physiological and metabolic flexibility during short-term changes in phosphate supply. The aim of this investigation was therefore to determine the physiological and metabolic flexibility of these organs during short-term supply of elevated phosphate nutrition. L. albus was cultivated in sand culture for 4 weeks at 0.1 mM phosphate supply, and then supplied with 2 mM phosphate for 2 weeks. Short-term elevated phosphate supply caused increased allocation of carbon and respiratory costs to nodules, at the expense of cluster root function. This alteration was also reflected in the increase in nodule enzyme activities related to organic acid synthesis, such as Phosphoenol-pyruvate Carboxylase (PEPC), Pyruvate Kinase (PK), Malate Dehydrogenase(NADH-MDH) and Malic Enzyme (ME). In cluster roots, elevated phosphate conditions caused a decline in these organic acid synthesizing enzymes. Phosphate recycling via Acid Phosphatase (APase),declined in nodules with elevated phosphate supply, but increased in cluster roots. Our findings suggest that during short-term elevated phosphate supply, there is a great degree of physiological and metabolic flexibility in lupin nutrient acquiring structures, and that these changes are related to the altered physiology of these organs [corrected]. Copyright © 2014 Elsevier GmbH. All rights reserved.

  18. Fatty acid and amino acid modulation of glucose cycling in isolated rat hepatocytes

    NARCIS (Netherlands)

    Gustafson, LA; Neeft, M; Reijngoud, DJ; Kuipers, F; Sauerwein, HP; Romijn, JA; Herling, AW; Burger, HJ; Meijer, AJ

    2001-01-01

    We studied the influence of glucose/glucose 6-phosphate cycling on glycogen deposition from glucose in fasted-rat hepatocytes using S4048 and CP320626, specific inhibitors of glucose-6-phosphate translocase and glycogen phosphorylase respectively. The effect of amino acids and oleate was also

  19. Genetics Home Reference: pyridoxal 5'-phosphate-dependent epilepsy

    Science.gov (United States)

    ... 5'-phosphate-dependent epilepsy Pyridoxal 5'-phosphate-dependent epilepsy Printable PDF Open All Close All Enable Javascript ... expand/collapse boxes. Description Pyridoxal 5'-phosphate-dependent epilepsy is a condition that involves seizures beginning soon ...

  20. Novel oral phosphate binder with nanocrystalline maghemite-phosphate binding capacity and pH effect.

    Science.gov (United States)

    Nguyen, T M-H; Müller, R H; Taupitz, M; Schnorr, J; Hamm, B; Wagner, S

    2015-03-30

    Hyperphosphatemia is one of the main risk factors contributing to morbidity and mortality in patients with end stage renal disease. The demand for a new phosphate binder is continuously increasing since the number of patients suffering under hyperphosphatemia is growing. However, side effects and high pill burden of currently available phosphate binders are the main reasons for low compliance and uncontrolled serum phosphate levels. Therefore, the aim of this study was to develop a novel phosphate binder with a high phosphate binding capacity over the entire gastrointestinal (GI) pH range. This novel phosphate binder C-PAM-10 is based on d-mannose coated nanocrystalline maghemite and belongs to the new class of phosphate binders, called the "iron based agents". It was possible to obtain a phosphate binding product that showed very high phosphate binding capacities with the characteristic of being pH independent at relevant pH ranges. The simulation of a GI passage ranging from pH 1.2 to pH 7.5 showed a 2.5 times higher phosphate binding capacity compared to the commonly used phosphate binder sevelamer carbonate. The simulation of a pH sensitive coating that releases the iron based phosphate binder at pH values ≥4.5 still showed a very high phosphate binding capacity combined with very low iron release which might decrease iron related side effects in vivo. Therefore, C-PAM-10 and its variations may be very promising candidates as a superior phosphate binder. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Long-term biological performance of injectable and degradable calcium phosphate cement

    NARCIS (Netherlands)

    Grosfeld, E.C.; Hoekstra, J.W.M.; Herber, R.P.; Ulrich, D.J.O.; Jansen, J.A.; Beucken, J.J.J.P van den

    2016-01-01

    Enhancing degradation of poorly degrading injectable calcium phosphate (CaP) cements (CPCs) can be achieved by adding poly(lactic-co-glycolic acid) (PLGA) microparticles, generating porosity after polymer degradation. CPC-PLGA has proven to be biodegradable, although its long-term biological

  2. Microbial community changes in biological phosphate-removal systems on altering sludge phosphorus content

    NARCIS (Netherlands)

    Liu, WT; Linning, KD; Nakamura, K; Mino, T; Matsuo, T; Forney, LJ

    Biomarkers (respiratory quinones and cellular fatty acids) and denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rRNA genes were used to characterize the microbial community structure of lab-scale enhanced biological phosphate-removal (EBPR) systems in response to altering sludge

  3. Evaluation of the biocompatibility of calcium phosphate cement/PLGA microparticle composites.

    NARCIS (Netherlands)

    Link, D.P.; Dolder, J. van den; Beucken, J.J.J.P van den; Cuijpers, V.M.J.I.; Wolke, J.G.C.; Mikos, A.G.; Jansen, J.A.

    2008-01-01

    In this study, the biocompatibility of a calcium phosphate (CaP) cement incorporating poly (D,L-lactic-co-glycolic acid) (PLGA) microparticles was evaluated in a subcutaneous implantation model in rats. Short-term biocompatibility was assessed using pure CaP discs and CaP discs incorporating PLGA

  4. PLGA microsphere/calcium phosphate cement composites for tissue engineering: in vitro release and degradation characteristics.

    NARCIS (Netherlands)

    Habraken, W.J.E.M.; Wolke, J.G.C.; Mikos, A.G.; Jansen, J.A.

    2008-01-01

    Bone cements with biodegradable poly(lactic-co-glycolic acid) (PLGA) microspheres have already been proven to provide a macroporous calcium phosphate cement (CPC) during in situ microsphere degradation. Furthermore, in vitro/in vivo release studies with these PLGA microsphere/CPC composites

  5. Incorporation of bioactive glass in calcium phosphate cement: Material characterization and in vitro degradation

    NARCIS (Netherlands)

    Renno, A.C.; Nejadnik, M.R.; Watering, F.C.J. van de; Crovace, M.C.; Zanotto, E.D.; Hoefnagels, J.P.; Wolke, J.G.C.; Jansen, Jan; Beucken, J.J.J.P van den

    2013-01-01

    Calcium phosphate cements (CPCs) have been widely used as an alternative to biological grafts due to their excellent osteoconductive properties. Although degradation has been improved by using poly(D,L-lactic-co-glycolic) acid (PLGA) microspheres as porogens, the biological performance of CPC/PLGA

  6. In vitro degradation rate of apatitic calcium phosphate cement with incorporated PLGA microspheres

    NARCIS (Netherlands)

    Felix Lanao, R.P.; Leeuwenburgh, S.C.G.; Wolke, J.G.C.; Jansen, J.A.

    2011-01-01

    Calcium phosphate cements (CPCs) are frequently used as bone substitute material. Despite their superior clinical handling and excellent biocompatibility, they exhibit poor degradability, which limits bone ingrowth into the implant. Microspheres were prepared from poly(d,l-lactic-co-glycolic acid)

  7. Maxillary sinus floor augmentation with injectable calcium phosphate cements: a pre-clinical study in sheep

    NARCIS (Netherlands)

    Hoekstra, J.W.M.; Klijn, R.J.; Meijer, G.J.; Beucken, J.J.J.P van den; Jansen, J.B.M.J.

    2013-01-01

    OBJECTIVES: The aim of this pre-clinical study was to evaluate the biological performance of two injectable calcium phosphate cement (CPC) composite materials containing poly(D,L-lactic-co-glycolic)acid (PLGA) microspheres with different properties in a maxillary sinus floor elevation model in

  8. Mechanical evaluation of implanted calcium phosphate cement incorporated with PLGA microparticles.

    NARCIS (Netherlands)

    Link, D.P.; Dolder, J. van den; Jurgens, W.J.; Wolke, J.G.C.; Jansen, J.A.

    2006-01-01

    In this study, the mechanical properties of an implanted calcium phosphate (CaP) cement incorporated with 20wt% poly (dl-lactic-co-glycolic acid) (PLGA) microparticles were investigated in a rat cranial defect. After 2, 4 and 8 weeks of implantation, implants were evaluated mechanically (push-out

  9. A Supramolecular Sensing Platform for Phosphate Anions and an Anthrax Biomarker in a Microfluidic Device

    NARCIS (Netherlands)

    Eker, B.; Yilmaz, M.D.; Schlautmann, Stefan; Gardeniers, Johannes G.E.; Huskens, Jurriaan

    2011-01-01

    A supramolecular platform based on self-assembled monolayers (SAMs) has been implemented in a microfluidic device. The system has been applied for the sensing of two different analyte types: biologically relevant phosphate anions and aromatic carboxylic acids, which are important for anthrax

  10. Manganese Phosphate Self-assembled Nanoparticle Surface and Its application for Superoxide Anion Detection

    National Research Council Canada - National Science Library

    Shen, Xiaohui; Wang, Qi; Liu, Yuhong; Xue, Wenxiao; Ma, Lie; Feng, Shuaihui; Wan, Mimi; Wang, Fenghe; Mao, Chun

    2016-01-01

    .... Herein, a novel Mn-superoxide dismutase (MnSOD) mimics, silica-manganous phosphate (SiO2-Mn3(PO4)2) nanoparticles, were designed and synthesized by surface self-assembly processes that occur on the surface of silica-phytic acid...

  11. The return of metabolism: biochemistry and physiology of the pentose phosphate pathway

    NARCIS (Netherlands)

    Stincone, A.; Prigione, A.; Cramer, T.; Wamelink, M.M.C.; Campbell, K.; Cheung, E.; Olin-Sandoval, V.; Gruning, N.M.; Kruger, A.; Alam, M.T.; Keller, M.A.; Breitenbach, M.; Brindle, K.M.; Rabinowitz, J.D.; Ralser, M.

    2015-01-01

    The pentose phosphate pathway (PPP) is a fundamental component of cellular metabolism. The PPP is important to maintain carbon homoeostasis, to provide precursors for nucleotide and amino acid biosynthesis, to provide reducing molecules for anabolism, and to defeat oxidative stress. The PPP shares

  12. Determination of uranium content in phosphate ores using different measurement techniques

    Directory of Open Access Journals (Sweden)

    Mohammad A. Al-Eshaikh

    2016-01-01

    Full Text Available The most important unconventional source of uranium is found in phosphate deposits; unfortunately, nowadays its exploitation is limited by economic constraints. The uranium concentrations in phosphate ores in the world vary regionally and most countries with large phosphate deposits have either plant in operation to extract uranium or are at the stage of pilot extraction plants. The aim of this investigation is to evaluate uranium content in the Saudi phosphate ores for, at least, two reasons: firstly, upgrading the phosphate quality by removing the uranium content in order to reduce the radioactivity in the fertilizer products. Secondly, getting benefit from the extracted uranium for its domestic use as a fuel in nuclear power and desalination plants. The results of this study show that the uranium concentration in Saudi phosphate rocks is relatively low (less than 100 ppm, which is not economically encouraging for its direct extraction. However, its extraction as a byproduct from the phosphoric acid, which will have higher concentration could be quite promising and worth exploiting.

  13. Bench-scale study of the effect of phosphate on an aerobic iron oxidation plant for mine water treatment.

    Science.gov (United States)

    Tischler, Judith S; Wiacek, Claudia; Janneck, Eberhard; Schlömann, Michael

    2014-01-01

    At the opencast pit Nochten acidic iron- and sulfate-rich mine waters are treated biotechnologically in a mine-water treatment plant by microbial iron oxidation. Due to the low phosphate concentration in such waters the treatment plant was simulated in bench-scale to investigate the influence of addition of potassium dihydrogen phosphate on chemical and biological parameters of the mine-water treatment. As a result of the phosphate addition the number of cells increased, which resulted in an increase of the iron oxidation rate in the reactor with phosphate addition by a factor of 1.7 compared to a reference approach without phosphate addition. Terminal restriction fragment length polymorphism (T-RFLP) analysis during the cultivation revealed a shift of the microbial community depending on the phosphate addition. While almost exclusively iron-oxidizing bacteria related to "Ferrovum" sp. were detected with phosphate addition, the microbial community was more diverse without phosphate addition. In the latter case, iron-oxidizing bacteria ("Ferrovum" sp., Acidithiobacillus spp.) as well as non-iron-oxidizing bacteria (Acidiphilium sp.) were identified. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. DHEA-Mediated Inhibition of the Pentose Phosphate Pathway Alters Oocyte Lipid Metabolism in Mice

    Science.gov (United States)

    Jimenez, Patricia T.; Frolova, Antonina I.; Chi, Maggie M.; Grindler, Natalia M.; Willcockson, Alexandra R.; Reynolds, Kasey A.; Zhao, Quihong

    2013-01-01

    Women with polycystic ovary syndrome (PCOS) and hyperandrogenism have altered hormone levels and suffer from ovarian dysfunction leading to subfertility. We have attempted to generate a model of hyperandrogenism by feeding mice chow supplemented with dehydroepiandrosterone (DHEA), an androgen precursor that is often elevated in women with PCOS. Treated mice had polycystic ovaries, low ovulation rates, disrupted estrous cycles, and altered hormone levels. Because DHEA is an inhibitor of glucose-6-phosphate dehydrogenase, the rate-limiting enzyme in the pentose phosphate pathway, we tested the hypothesis that oocytes from DHEA-exposed mice would have metabolic disruptions. Citrate levels, glucose-6-phosphate dehydrogenase activity, and lipid content in denuded oocytes from these mice were significantly lower than controls, suggesting abnormal tricarboxylic acid and pentose phosphate pathway metabolism. The lipid and citrate effects were reversible by supplementation with nicotinic acid, a precursor for reduced nicotinamide adenine dinucleotide phosphate. These findings suggest that elevations in systemic DHEA can have a negative impact on oocyte metabolism and may contribute to poor pregnancy outcomes in women with hyperandrogenism and PCOS. PMID:24036000

  15. Chemical and enzymatic methodologies for the synthesis of enantiomerically pure glyceraldehyde 3-phosphates.

    Science.gov (United States)

    Gauss, Dominik; Schoenenberger, Bernhard; Wohlgemuth, Roland

    2014-05-07

    Glyceraldehyde 3-phosphates are important intermediates of many central metabolic pathways in a large number of living organisms. d-Glyceraldehyde 3-phosphate (d-GAP) is a key intermediate during glycolysis and can as well be found in a variety of other metabolic pathways. The opposite enantiomer, l-glyceraldehyde 3-phosphate (l-GAP), has been found in a few exciting new pathways. Here, improved syntheses of enantiomerically pure glyceraldehyde 3-phosphates are reported. While d-GAP was synthesized by periodate cleavage of d-fructose 6-phosphate, l-GAP was obtained by enzymatic phosphorylation of l-glyceraldehyde. (1)H- and (31)P NMR spectroscopy was applied in order to examine pH-dependent behavior of GAP over time and to identify potential degradation products. It was found that GAP is stable in acidic aqueous solution below pH 4. At pH 7, methylglyoxal is formed, whereas under alkaline conditions, the formation of lactic acid could be observed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Developing porous carbon with dihydrogen phosphate groups as sulfur host for high performance lithium sulfur batteries

    Science.gov (United States)

    Cui, Yanhui; Zhang, Qi; Wu, Junwei; Liang, Xiao; Baker, Andrew P.; Qu, Deyang; Zhang, Hui; Zhang, Huayu; Zhang, Xinhe

    2018-02-01

    Carbon matrix (CM) derived from biomass is low cost and easily mass produced, showing great potential as sulfur host for lithium sulfur batteries. In this paper we report on a dihydrogen phosphate modified CM (PCM-650) prepared from luffa sponge (luffa acutangula) by phosphoric acid treatment. The phosphoric acid not only increases the surface area of the PCM-650, but also introduces dihydrogen phosphate onto PCM-650 (2.28 at% P). Sulfur impregnated (63.6 wt%) PCM-650/S, in comparison with samples with less dihydrogen phosphate LPCM-650/S, shows a significant performance improvement. XPS analysis is conducted for sulfur at different stages, including sulfur (undischarged), polysulfides (discharge to 2.1 V) and short chain sulfides (discharge to 1.7 V). The results consistently show chemical shifts for S2p in PCM-650, suggesting an enhanced adsorption effect. Furthermore, density functional theory (DFT) calculations is used to clarify the molecular binding: carbon/sulfur (0.86 eV), carbon/Li2S (0.3 eV), CH3-O-PO3H2/sulfur (1.24 eV), and CH3-O-PO3H2/Li2S (1.81 eV). It shows that dihydrogen phosphate group can significantly enhance the binding with sulfur and sulfide, consistent with XPS results. Consequently a CM functionalised with dihydrogen phosphate shows great potential as the sulfur host in a Li-S battery.

  17. Investigation of the Amount of Phosphate and Nitrate Accumulation in Consumable Onion in Hamedan City

    Directory of Open Access Journals (Sweden)

    2017-02-01

    Full Text Available Introduction Consumption more of level nitrate and phosphates threatens human health. Vegetable and fruits are the great sources of nitrate and phosphate in human diet. The purpose of study is to determine the amount of nitrate and phosphate in consuming onions of Hamedan. Materials and Methods Sampling performed randomly to number of 10 onion samples in 3 repetition in April and February 2015 & 2016. Concentration of nitrate and phosphates analyzed by spectrophotometer after extracting by method acid digestion and dry ash. For statistical processing of results used from software SPSS v.20 and T-independent and one sample T-test. Results Results showed that nitrate average in white and red onions in April was 60.65mg/kg and 275.97mg/kg respectively and in February was 194.85mg/kg and 244.67mg/kg respectively. Also phosphate average in white and red onions in April is 6205.11mg/kg and 13526.87 mg/kg respectively and in February is 6124.12 mg/kg and 7512.11 mg/kg respectively. Conclusion Findings showed that the concentration of nitrate and phosphate in red onions of collected in April and white onions collected in February are more than WHO standard. In this study the reason of high nitrate and phosphate in the consumed onions in Hamedan is probably use of unsuitable, unbalanced and high amount of nitrate and phosphate manures. Therefore regular monitor of products by “Deputy of Food and Drug” of Medical Science University is seems to be necessary. 

  18. Effect of Potassium Citrate on Calcium Phosphate Stones in a Model of Hypercalciuria

    Science.gov (United States)

    Asplin, John R.; Frick, Kevin K.; Granja, Ignacio; Culbertson, Christopher D.; Ng, Adeline; Grynpas, Marc D.; Bushinsky, David A.

    2015-01-01

    Potassium citrate is prescribed to decrease stone recurrence in patients with calcium nephrolithiasis. Citrate binds intestinal and urine calcium and increases urine pH. Citrate, metabolized to bicarbonate, should decrease calcium excretion by reducing bone resorption and increasing renal calcium reabsorption. However, citrate binding to intestinal calcium may increase absorption and renal excretion of both phosphate and oxalate. Thus, the effect of potassium citrate on urine calcium oxalate and calcium phosphate supersaturation and stone formation is complex and difficult to predict. To study the effects of potassium citrate on urine supersaturation and stone formation, we utilized 95th-generation inbred genetic hypercalciuric stone-forming rats. Rats were fed a fixed amount of a normal calcium (1.2%) diet supplemented with potassium citrate or potassium chloride (each 4 mmol/d) for 18 weeks. Urine was collected at 6, 12, and 18 weeks. At 18 weeks, stone formation was visualized by radiography. Urine citrate, phosphate, oxalate, and pH levels were higher and urine calcium level was lower in rats fed potassium citrate. Furthermore, calcium oxalate and calcium phosphate supersaturation were higher with potassium citrate; however, uric acid supersaturation was lower. Both groups had similar numbers of exclusively calcium phosphate stones. Thus, potassium citrate effectively raises urine citrate levels and lowers urine calcium levels; however, the increases in urine pH, oxalate, and phosphate levels lead to increased calcium oxalate and calcium phosphate supersaturation. Potassium citrate induces complex changes in urine chemistries and resultant supersaturation, which may not be beneficial in preventing calcium phosphate stone formation. PMID:25855777

  19. Chemical modification of coal fly ash for the removal of phosphate from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    P. Pengthamkeerati; T. Satapanajaru; P. Chularuengoaksorn [Kasetsart University, Bangkok (Thailand). Environmental Technology Research Unit (EnviTech), Department of Environmental Science

    2008-09-15

    This study investigated the chemical modifications of coal fly ash treated with HCl and NaOH. Sorption behavior of phosphate from water solution on treated fly ash was examined. Results showed that the HCl-treated fly ash (TFA-HCl) had a greater specific surface area (SSA) than the NaOH-treated fly ash (TFA-NaOH) and untreated fly ash (FA). The XRF, XRD patterns, and SEM images revealed the decreased CaO content in the TFA-HCl and observed the presence of NaP1 and sodalite zeolites in the TFA-NaOH. The P sorption capacity of all studied fly ashes increased with increasing initial P concentration and mechanisms of P sorption were influenced by the equilibrium pH. Maximum phosphate immobilization capacity obtained from Langmuir model was in the following manner, TFA-NaOH > FA > TFA-HCl (57.14, 23.20, and 6.90 mg P g{sup -1}, respectively). The decreased CaO content and acidic pH in the TFA-HCl were responsible for the lowest capacity of phosphate immobilization, because of unfavorable condition for calcium phosphate precipitation. In contrast, due to alkaline condition and relatively high calcium content, the precipitation of calcium phosphate was a key mechanism for phosphate removal in the FA and TFA-NaOH. The TFA-NaOH had a greatest phosphate immobilization, due to high CaO content and an increased SSA after the conversion of fly ash to zeolite. Both Langmuir and Freundlich models were good fitted for the TFA-NaOH, while was only Langmuir model for the FA and Freundlich model for the TFA-HCl. Results suggested that treating fly ash with alkaline solution was a promising way to enhance phosphate immobilization. 23 refs., 7 figs., 2 tabs.

  20. Remnants of an Ancient Metabolism without Phosphate.

    Science.gov (United States)

    Goldford, Joshua E; Hartman, Hyman; Smith, Temple F; Segrè, Daniel

    2017-03-09

    Phosphate is essential for all living systems, serving as a building block of genetic and metabolic machinery. However, it is unclear how phosphate could have assumed these central roles on primordial Earth, given its poor geochemical accessibility. We used systems biology approaches to explore the alternative hypothesis that a protometabolism could have emerged prior to the incorporation of phosphate. Surprisingly, we identified a cryptic phosphate-independent core metabolism producible from simple prebiotic compounds. This network is predicted to support the biosynthesis of a broad category of key biomolecules. Its enrichment for enzymes utilizing iron-sulfur clusters, and the fact that thermodynamic bottlenecks are more readily overcome by thioester rather than phosphate couplings, suggest that this network may constitute a "metabolic fossil" of an early phosphate-free nonenzymatic biochemistry. Our results corroborate and expand previous proposals that a putative thioester-based metabolism could have predated the incorporation of phosphate and an RNA-based genetic system. PAPERCLIP. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  1. Phosphate Favors the Biosynthesis of CdS Quantum Dots in Acidithiobacillus thiooxidans ATCC 19703 by Improving Metal Uptake and Tolerance

    Directory of Open Access Journals (Sweden)

    Giovanni Ulloa

    2018-02-01

    Full Text Available Recently, we reported the production of Cadmium sulfide (CdS fluorescent semiconductor nanoparticles (quantum dots, QDs by acidophilic bacteria of the Acidithiobacillus genus. Here, we report that the addition of inorganic phosphate to Acidithiobacillus thiooxidans ATCC 19703 cultures favors the biosynthesis of CdS QDs at acidic conditions (pH 3.5. The effect of pH, phosphate and cadmium concentrations on QDs biosynthesis was studied by using Response Surface Methodology (RSM, a multivariate technique for analytical optimization scarcely used in microbiological studies to date. To address how phosphate affects intracellular biosynthesis of CdS QDs, the effect of inorganic phosphate on bacterial cadmium-uptake was evaluated. By measuring intracellular levels of cadmium we determined that phosphate influences the capacity of cells to incorporate this metal. A relation between cadmium tolerance and phosphate concentrations was also determined, suggesting that phosphate participates in the adaptation of bacteria to toxic levels of this metal. In addition, QDs-biosynthesis was also favored by the degradation of intracellular polyphosphates. Altogether, our results indicate that phosphate contributes to A. thiooxidans CdS QDs biosynthesis by influencing cadmium uptake and cadmium tolerance. These QDs may also be acting as a nucleation point for QDs formation at acidic pH. This is the first study reporting the effect of phosphates on QDs biosynthesis and describes a new cadmium-response pathway present in A. thiooxidans and most probably in other bacterial species.

  2. Aquatic Toxicity Assessment of Phosphate Compounds

    Science.gov (United States)

    Kim, Eunju; Yoo, Sunkyoung; Ro, Hee-Young; Han, Hye-Jin; Baek, Yong-Wook; Eom, Ig-Chun; Kim, Pilje; Choi, Kyunghee

    2013-01-01

    Objectives Tricalcium phosphate and calcium hydrogenorthophosphate are high production volume chemicals, mainly used as foodstuff additives, pharmaceuticals, lubricants, synthetic resin, and disinfectants. Phosphate has the potential to cause increased algal growth leading to eutrophication in the aquatic environment. However, there is no adequate information available on risk assessment or acute and chronic toxicity. The aim of this research is to evaluate the toxic potential of phosphate compounds in the aquatic environment. Methods An aquatic toxicity test of phosphate was conducted, and its physico-chemical properties were obtained from a database recommended in the Organization for Economic Cooperation and Development (OECD) guidance manual. An ecotoxicity test using fish, Daphnia, and algae was conducted by the good laboratory practice facility according to the OECD TG guidelines for testing of chemicals, to secure reliable data. Results The results of the ecotoxicity tests of tricalcium phosphate and calcium hydrogenorthophosphate are as follows: In an acute toxicity test with Oryzias latipes, 96 hr 50% lethal concentration (LC50) was >100 (measured:>2.14) mg/L and >100 (measured: >13.5) mg/L, respectively. In the Daphnia test, 48 hr 50% effective concentration (EC50) was >100 (measured: >5.35) mg/L and >100 (measured: >2.9) mg/L, respectively. In a growth inhibition test with Pseudokirchneriella subcapitata, 72 hr EC50 was >100 (measured: >1.56) mg/L and >100 (measured: >4.4) mg/L, respectively. Conclusions Based on the results of the ecotoxicity test of phosphate using fish, Daphnia, and algae, L(E)C50 was above 100 mg/L (nominal), indicating no toxicity. In general, the total phosphorus concentration including phosphate in rivers and lakes reaches levels of several ppm, suggesting that phosphate has no toxic effects. However, excessive inflow of phosphate into aquatic ecosystems has the potential to cause eutrophication due to algal growth. PMID:23440935

  3. Polynucleotide 3′-terminal Phosphate Modifications by RNA and DNA Ligases

    Science.gov (United States)

    Zhelkovsky, Alexander M.; McReynolds, Larry A.

    2014-01-01

    RNA and DNA ligases catalyze the formation of a phosphodiester bond between the 5′-phosphate and 3′-hydroxyl ends of nucleic acids. In this work, we describe the ability of the thermophilic RNA ligase MthRnl from Methanobacterium thermoautotrophicum to recognize and modify the 3′-terminal phosphate of RNA and single-stranded DNA (ssDNA). This ligase can use an RNA 3′p substrate to generate an RNA 2′,3′-cyclic phosphate or convert DNA3′p to ssDNA3′pp5′A. An RNA ligase from the Thermus scotoductus bacteriophage TS2126 and a predicted T4 Rnl1-like protein from Thermovibrio ammonificans, TVa, were also able to adenylate ssDNA 3′p. These modifications of RNA and DNA 3′-phosphates are similar to the activities of RtcA, an RNA 3′-phosphate cyclase. The initial step involves adenylation of the enzyme by ATP, which is then transferred to either RNA 3′p or DNA 3′p to generate the adenylated intermediate. For RNA 3′pp5′A, the third step involves attack of the adjacent 2′ hydroxyl to generate the RNA 2′,3′-cyclic phosphate. These steps are analogous to those in classical 5′ phosphate ligation. MthRnl and TS2126 RNA ligases were not able to modify a 3′p in nicked double-stranded DNA. However, T4 DNA ligase and RtcA can use 3′-phosphorylated nicks in double-stranded DNA to produce a 3′-adenylated product. These 3′-terminal phosphate-adenylated intermediates are substrates for deadenylation by yeast 5′Deadenylase. Our findings that classic ligases can duplicate the adenylation and phosphate cyclization activity of RtcA suggests that they have an essential role in metabolism of nucleic acids with 3′-terminal phosphates. PMID:25324547

  4. Removal of trace arsenic(V) and phosphate from water by a highly selective ligand exchange adsorbent.

    Science.gov (United States)

    Awual, Md Rabiul; El-Safty, Sherif A; Jyo, Akinori

    2011-01-01

    A highly selective ligand exchange type adsorbent was developed for the removal of trace arsenic(V) (As(V)) and phosphate from water. This adsorbent was prepared by loading zirconium(IV) on monophosphonic acid resin. This adsorbent was able to remove toxic anions efficiently at wide pH ranges. However, low pH was preferable for maximum breakthrough capacity in an adsorption operation. The effect of a large amount of competing anions such as chloride, bicarbonate, and sulfate on the adsorption systems of As(V) and phosphate anions was investigated. The experimental findings revealed that the As(V) and phosphate uptakes were not affected by these competing anions despite the enhancement of the breakthrough points and total adsorption. Phosphate anion was slightly preferable than As(V) in their competitive adsorption by the adsorbent. The adsorbed As(V) and phosphate on the Zr(IV)-loaded resin were quantitatively eluted with 0.1 mol/L sodium hydroxide solution, and the adsorbent was regenerated by 0.5 mol/L sulfuric acid. During several cycles of adsorption-elution-regeneration operations, no Zr(IV) was detected in the column effluents. Therefore, the Zr(IV)-loaded monophosphonic acid resin is an effective ligand exchange adsorbent for removing trace concentrations of As(V) and phosphate from water.

  5. Long- and short-term phosphate deprivation in bean roots: plasma membrane lipid alterations and transient stimulation of phospholipases.

    Science.gov (United States)

    Russo, Marco Antonio; Quartacci, Mike F; Izzo, Riccardo; Belligno, Adalgisa; Navari-Izzo, Flavia

    2007-06-01

    In a long-term experiment bean (Phaseolus vulgaris L.) seedlings were grown for 18 days in hydroponics in either phosphate-sufficient (+P) or phosphate-deficient (-P) nutrient solutions. Phosphate deprivation halved the phosphorous content of roots. In plasma membrane (PM) fractions isolated from -P roots the phospholipid (PL) level was reduced from 35 to 21 mol%, while PL composition and degree of unsaturation were hardly altered. Digalactosyldiacylglycerol (DGDG) accumulated up to 26% of total PM lipids, replacing PL to a large extent. Molecular species and fatty acid compositions of DGDG in root PM were different compared to DGDG present in the -P plastids. In a short-term study, bean seedlings were grown for 18 days in hydroponics with a complete nutrient solution containing phosphate and then incubated in a -P medium for increasing time ranging from 1 up to 96 h. At the end of the starvation period phosphorous content of -P roots was reduced by 30% compared to +P ones. An activation of phospholipase D and phospholipase C was observed after 1 and 2h of phosphate deprivation, respectively. Maximal phosphatidic acid accumulation was detected after 4h of phosphate deprivation, when also DGDG started to accumulate in PM of bean roots. The fatty acid composition of PLD-derived phosphatidylbutanol resembled that of phosphatidylcholine.

  6. BISMUTH PHOSPHATE CARRIER PROCESS FOR Pu RECOVERY

    Science.gov (United States)

    Finzel, T.G.

    1959-02-01

    An improvement in the bismuth phosphate carrier precipitation process for recovering plutonium is described. It has been found that a more granular and more easily filterable carrier precipitiite is formed if the addition of the bismuth and phosphate ions is effected by first adding 9/10 of the bismuth ions necessary, then slowly adding all of the source of the phosphate ions to be incorporated in the precipitate, while digesting at 75 C and afterwards incorporating the remainder of the total bismuth ions necessary

  7. Inhibition of Recombinant Aldose-6-Phosphate Reductase from Peach Leaves by Hexose-Phosphates, Inorganic Phosphate and Oxidants.

    Science.gov (United States)

    Hartman, Matías D; Figueroa, Carlos M; Arias, Diego G; Iglesias, Alberto A

    2017-01-01

    Glucitol, also known as sorbitol, is a major photosynthetic product in plants from the Rosaceae family. This sugar alcohol is synthesized from glucose-6-phosphate by the combined activities of aldose-6-phosphate reductase (Ald6PRase) and glucitol-6-phosphatase. In this work we show the purification and characterization of recombinant Ald6PRase from peach leaves. The recombinant enzyme was inhibited by glucose-1-phosphate, fructose-6-phosphate, fructose-1,6-bisphosphate and orthophosphate. Oxidizing agents irreversibly inhibited the enzyme and produced protein precipitation. Enzyme thiolation with oxidized glutathione protected the enzyme from insolubilization caused by diamide, while incubation with NADP+ (one of the substrates) completely prevented enzyme precipitation. Our results suggest that Ald6PRase is finely regulated to control carbon partitioning in peach leaves. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  8. Corrosion resistance of phosphatized steel: evaluation by electrochemical impedance spectroscopy; Resistencia a corrosao de aco fosfatizado: determinacao por espectroscopia de impedancia eletroquimica

    Energy Technology Data Exchange (ETDEWEB)

    Garita, Jose S. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Lab. de Corrosao e Protecao de Metais (LACOR); Fraga, Celia S. de; Ferreira, Jane Z.

    1996-12-31

    A zinc phosphate coating on steel consist in a crystal phosphate deposit with variable morphology and size. Crystalline deposits are obtained by a combination of electrochemical and chemical reactions between phosphoric acid and metal. The deposit thickness and crystal size are characteristics of the phosphatizing bath. Two usual phosphate applications are: increase anchor profile for a better adhesion of organic coatings and tribological applications in mechanical conformation, for example. In anticorrosion protection system base on phosphate, the phosphate coating has a function to be final resistant corrosion barrier and is associated with the restriction of the cathodic lost of adherence in the remainder protective system. The aim of this work is study the corrosion resistance properties of three different phosphate coatings on steel. These phosphate coatings are obtained with a change in the standard zinc phosphate bath. An alternative methodology at the conventional analysis technique, based on electrochemical impedance spectroscopy is suggested. The resistance polarization (Rp) obtained by EIS have a good agreement with the corrosion levels observed in the accelerated corrosion test (ASTM D2247). An adequate standardization for this technique can be the conventional test for characterization of phosphate coatings. (author) 6 refs., 5 figs., 2 tabs.

  9. Corrosion behavior of zirconia in acidulated phosphate fluoride

    Science.gov (United States)

    Thomas, Anie; Sridhar, Sathyanarayanan; Aghyarian, Shant; Watkins-curry, Pilanda; Chan, Julia Y.; Pozzi, Alessandro; Rodrigues, Danieli C.

    2016-01-01

    ABSTRACT Objective The corrosion behavior of zirconia in acidulated phosphate fluoride (APF) representing acidic environments and fluoride treatments was studied. Material and Methods Zirconia rods were immersed in 1.23% and 0.123% APF solutions and maintained at 37°C for determined periods of time. Surfaces of all specimens were imaged using digital microscopy and scanning electron microscopy (SEM). Sample mass and dimensions were measured for mass loss determination. Samples were characterized by powder X-ray diffraction (XRD) to detect changes in crystallinity. A biosensor based on electrochemical impedance spectroscopy (EIS) was used to detect ion dissolution of material into the immersion media. Results Digital microscopy revealed diminishing luster of the materials and SEM showed increased superficial corrosion of zirconia submerged in 1.23% APF. Although no structural change was found, the absorption of salts (sodium phosphate) onto the surface of the materials bathed in 0.123% APF was significant. EIS indicated a greater change of impedance for the immersion solutions with increasing bathing time. Conclusion Immersion of zirconia in APF solutions showed deterioration limited to the surface, not extending to the bulk of the material. Inferences on zirconia performance in acidic oral environment can be elucidated from the study. PMID:27008257

  10. Evaluating the effectiveness of phosphate fertilizers in some Venezuelan soils

    Energy Technology Data Exchange (ETDEWEB)

    Casanova, E. [Instituto de Edafologia, Facultad de Agronomia, Universidad Central de Venezuela, Maracay, Aragua (Venezuela)]. E-mail: casanova@pdvsa.com; Salas, A.M. [Instituto de Edafologia, Facultad de Agronomia, Universidad Central de Venezuela, Maracay, Aragua (Venezuela); Toro, M. [Instituto de Zoologia Tropical, Facultad de Ciencias, Universidad Central de Venezuela, Caraca (Venezuela)

    2002-05-15

    In Venezuela, 70% of the soils are acid with low natural fertility where phosphorus is the most limiting element together with nitrogen and potassium for plant growth. The efficiency of phosphate fertilization is low. Greenhouse and field experiments were conducted to evaluate the efficiency of natural and modified rock phosphate using conventional and isotopic techniques. An incubation experiment was done to measure changes in available P on application of different phosphate fertilizers at a constant rate of 100 mg P/kg in ten acid soils of agricultural importance in Venezuela. In the greenhouse, two experiments were conducted to relate P fixation to soil P availability and the response of an index plant (Agrostis sp.). A high variability in P fixing capacity of the soils (r1/Ro = 0.02-0.76) was observed with the same level of available P. This fixation index is defined as the proportion of the added radioactivity ({sup 32}P) remaining in the soil solution after 1 min of exchange and a low fixing capacity is indicated by the values close to 1. The proportion of the total soil P that can possibly enter the soil solution and therefore is potentially available for plant uptake was measured using the traditional method (Bray I) and the isotopic method (E value). The high variability was also apparent in available P extracted by Bray I showing a range of 10 to 88% of the total P removed by the extracting solution. The incubation studies showed that the effectiveness of the P source for available P in the soil solution was related to their reactivity and the soil P fixing properties. The increase in the fixing capacity of the soils used caused a significant reduction in the E value, independent of the source of P used. A high positive and significant correlation between Bray I extracted P and the E value (r = 0.95) obtained from the different treatments, showed the relationship of the extractant for some forms of available P in soils where rock phosphate was applied

  11. In vivo Dentin Microhardness beneath a Calcium-Phosphate Cement

    Science.gov (United States)

    Bresciani, E.; Wagner, W.C.; Navarro, M.F.L.; Dickens, S.H.; Peters, M.C.

    2010-01-01

    A minimally invasive caries-removal technique preserves potentially repairable, caries-affected dentin. Mineral-releasing cements may promote remineralization of soft residual dentin. This study evaluated the in vivo remineralization capacity of resin-based calcium-phosphate cement (Ca-PO4) used for indirect pulp-capping. Permanent carious and sound teeth indicated for extraction were excavated and restored either with or without the Ca-PO4 base (control), followed by adhesive restoration. Study teeth were extracted after 3 months, followed by sectioning and in vitro microhardness analysis of the cavity floor to 115-µm depth. Caries-affected dentin that received acid conditioning prior to Ca-PO4 basing showed significantly increased Knoop hardness near the cavity floor. The non-etched group presented results similar to those of the non-treated group. Acid etching prior to cement application increased microhardness of residual dentin near the interface after 3 months in situ. PMID:20511564

  12. Compositions containing amino acids, phosphate and manganese and their uses

    Energy Technology Data Exchange (ETDEWEB)

    Daly, Michael J.; Gaidamakova, Elena K.

    2017-09-12

    The invention provides methods of producing vaccines directed against microorganisms, with the methods comprising culturing, harvesting and/or suspending the microorganism in the presence of a radiation-protective composition and irradiating the bacteria or viruses with a dose of radiation sufficient to render the microorganism replication-deficient and/or non-infective. The radiation-protective compositions used in the methods of the present invention comprise at least one nucleoside, at least one antioxidant and at least one small peptide. The invention also provides methods of rendering bacteria in culture resistant to ionizing radiation (IR), with these methods comprising culturing the bacteria in the presence of a radiation-protective composition.

  13. Compositions containing amino acids, phosphate and manganese and their uses

    Science.gov (United States)

    Daly, Michael J.; Gaidamakova, Elena K.

    2016-01-12

    The invention provides methods of producing vaccines directed against microorganisms, with the methods comprising culturing, harvesting and/or suspending the microorganism in the presence of a radiation-protective composition and irradiating the bacteria or viruses with a dose of radiation sufficient to render the microorganism replication-deficient and/or non-infective. The radiation-protective compositions used in the methods of the present invention comprise at least one nucleoside, at least one antioxidant and at least one small peptide. The invention also provides methods of rendering bacteria in culture resistant to ionizing radiation (IR), with these methods comprising culturing the bacteria in the presence of a radiation-protective composition.

  14. Fluorometric determination of free glucose and glucose 6-phosphate in cows' milk and other opaque matrices.

    Science.gov (United States)

    Larsen, Torben

    2015-01-01

    Analyses of free glucose and glucose 6-phosphate in milk have until now been dependent upon several time consuming and troublesome procedures. This has limited investigations in the area. The present article presents a new, reliable, analytical procedure, based on enzymatic degradation and fluorometric detection. Standards and control materials were based on milk that was stripped of intrinsic glucose and glucose 6-phosphate in order to obtain standards and samples based on the same matrix. The analysis works without pre-treatment of the samples, e.g. without centrifugation and precipitation of protein with acids. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Optimization of Porous Pellets for Phosphate Recovery

    Science.gov (United States)

    The poster presents the preliminary adsorption experiment showing that phosphate concentration is decreasing over time as well as presenting the kinetics models that best fit the data collected over 25 days.

  16. Electrodeposition of dicalcium phosphate dihydrate coatings on ...

    Indian Academy of Sciences (India)

    /fulltext/boms/036/03/0475-0481. Keywords. Electrodeposition; orientation; DCPD; hydroxyapatite. Abstract. Cathodic reduction of an aqueous solution containing dissolved calcium and phosphate ions results in the deposition of micrometer ...

  17. Hydrolysis of pyridoxal-5'-phosphate in plasma in conditions with raised alkaline phosphate.

    OpenAIRE

    Anderson, B B; O'Brien, H; Griffin, G.E.; Mollin, D L

    1980-01-01

    Hydrolysis of pyridoxal phosphate in plasma was demonstrated in patients with liver disease and other conditions with raised alkaline phosphatase, and this usually closely paralleled the alkaline phosphatase level, whether of liver or bone origin. The endogenous plasma pyridoxal phosphate was inversely related to the alkaline phosphatase, and plasma hydrolysis of pyridoxal phosphate may at least in part be responsible. Very large doses of vitamin B6 may be necessary to compensate for this hyd...

  18. Phosphate solubilizing bacteria around Indian peninsula

    Digital Repository Service at National Institute of Oceanography (India)

    De; Nair, S.; Chandramohan, D.

    of Marine Sciences Vol. 29, March 2000, pp. 48-51 Phosphate solubilizing bacteria around Indian peninsula M-J. B. D. De Souza, S. Nair & D. Chandramohan National Institute of Oceanography, Dona Paula, Goa 403 004 India Received 29 July 1998, revised 16... on to hydroxyapaptite medium11 and incubated for three days at room temperature. The phosphate solubilization was expressed as positive and negative depending on the halo formation. The cultures which showed halo formation around their colonies were considered...

  19. Isolation of phosphate-solubilizing fungus and its application in solubilization of rock phosphates.

    Science.gov (United States)

    Wu, Yingben; He, Yuelin; Yin, Hongmei; Chen, Wei; Wang, Zhen; Xu, Lijuan; Zhang, Aiqun

    2012-12-01

    Microorganisms have been obtained to improve the agronomic value of rock phosphates (RPs), but the phosphorus solubilizing rate by these approaches is very slow. It is important to explore a high-efficient phosphate-solubilizing approach with a kind of microorganisms. This study aimed to isolate a high-efficient level of phosphate-solubilizing fungus from rhizosphere soil samples phosphate mines (Liuyang County, Hunan province, China) and apply it in solubilization of RPs. The experiments were carried out by the conventional methodology for morphological and biochemical fungus characterization and the analysis of 18s rRNA sequence. Then the effects of time, temperature, initial pH, phosphorus (P) sources, RPs concentration, shaking speed and silver ion on the content of soluble P released by this isolate were investigated. The results showed this isolate was identified as Galactomyces geotrichum P14 (P14) in GeneBank and the maximum amount of soluble P was 1252.13 mg L(-1) within 40 h in a modified phosphate growth agar's medium (without agar) where contained tricalcium phosphate (TCP) as sole phosphate source. At the same time, it could release phosphate and solubilize various rock phosphates. The isolated fungus can convert RPs from insoluble form into plant available form and therefore it hold great potential for biofertilizers to enhance soil fertility and promote plant growth.

  20. Effects of rock phosphate amended with poultry manure on soil ...

    African Journals Online (AJOL)

    The effect of rock phosphate (Sokoto and Ogun rock phosphates) amended with poultry manure on soil available phosphate (P) and yield of maize and cowpea grown sequentially was evaluated for four cropping seasons. The results obtained showed superiority of single super phosphate (SSP) application over either ...

  1. Antimicrobial and Antioxidant Properties of Phosphates Used in Meat Products

    Directory of Open Access Journals (Sweden)

    Azim Şimşek

    2017-04-01

    Full Text Available Phosphates are widely used as food additives in meat products to increase the water-holding capacity, reduce the cooking loss and improve the textural properties. Furthermore, phosphates protect aroma and accelerate the formation of cured meat color as well as having antioxidant and antimicrobial effects. Many research about using phosphates in meat products showed that increasing chain length of phosphates improves antioxidant and antimicrobial effects. It has been stated that vacuum or modified atmosphere packaging, the use of phosphates with natural antioxidants and encapsulation of phosphates are useful approaches to enhance the antioxidant effects of phosphates. It has been reported that irradiation, vacuum or modified atmosphere packaging, storage at low temperature and the use of the salt provide strong synergistic effect on the antimicrobial properties of phosphates. In this review, researches about antioxidant and antimicrobial properties of phosphates and suggestions for the meat industry about industrial applications of phosphates are presented.

  2. Synthesis of some calcium phosphate crystals using the useful biomass for immobilization of microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Kohiruimaki, T, E-mail: kohi@hi-tech.ac.jp [Department of Technology, Hachinohe Institute of Technology, 88-1 Myo-oobiraki, Hachinohe-shi 031-8501 (Japan)

    2011-10-29

    Three sources of biomass generated by primary industry were used as the raw material for the synthesis of calcium phosphate crystals. Phosphoric acid was extracted from burned rice chaff using a 30% nitric acid solution, while scallop shells and gypsum of plasterboard were used as calcium sources. The calcium phosphate crystals were synthesized by a method involving homogeneous precipitation, and the relationship between the composition and shape of the crystals and the pH at the time of the precipitation was investigated. Monetite crystals in a petal form with a diameter ranging from 0.1 to 2 {mu}m were precipitated at pH 2.0, while granular apatite crystals with a mean diameter of 1 {mu}m were precipitated at pH 6.0. We also investigated the ability of the synthesized calcium phosphate crystals to immobilize lactic acid bacteria for practical use in industrial bioreactor. It was determined that monetite crystals with a diameter of 2 {mu}m had the highest ability to fix lactic acid bacteria. The population of lactic acid bacteria was estimated to exceed 1,300 bacteria per crystal surface of 50 {mu}m{sup 2} suggesting that these crystals may be of practical use in industrial fermenters.

  3. Calcium Phosphate Bone Cements Including Sugar Surfactants: Part Two—Injectability, Adhesive Properties and Biocompatibility

    Directory of Open Access Journals (Sweden)

    Fabienne Briand-Mesange

    2010-12-01

    Full Text Available Addition of sugar surfactants, sucrose fatty acid esters and alkylpolyglucosides to a calcium phosphate cement, designed for bone reconstruction, is described. Thanks to their adsorption at the surface of the calcium phosphate particles, the sugar surfactants allowed a full injectability and brought a very good workability. Injectability was measured by monitoring force-distance curves. With some of the selected sugar surfactants adhesive properties of the cement pastes were also observed, which were measured by tack tests. Finally, some properties related to biological applications are described, including gentamicine release and osteoblast viability experiments. The whole study demonstrates that addition of these mild surfactants improved several properties of the calcium phosphate cement, without impairing function.

  4. Calcium Phosphate Bone Cements Including Sugar Surfactants: Part Two-Injectability, Adhesive Properties and Biocompatibility.

    Science.gov (United States)

    Bercier, Ariane; Gonçalves, Stéphane; Autefage, Helène; Briand-Mesange, Fabienne; Lignon, Olivier; Fitremann, Juliette

    2010-12-02

    Addition of sugar surfactants, sucrose fatty acid esters and alkylpolyglucosides to a calcium phosphate cement, designed for bone reconstruction, is described. Thanks to their adsorption at the surface of the calcium phosphate particles, the sugar surfactants allowed a full injectability and brought a very good workability. Injectability was measured by monitoring force-distance curves. With some of the selected sugar surfactants adhesive properties of the cement pastes were also observed, which were measured by tack tests. Finally, some properties related to biological applications are described, including gentamicine release and osteoblast viability experiments. The whole study demonstrates that addition of these mild surfactants improved several properties of the calcium phosphate cement, without impairing function.

  5. Influence of Temperature and Ultrasonic Treatment on Preparation of Titanium Phosphates and Their Powder Properties

    Directory of Open Access Journals (Sweden)

    Hiroaki Onoda

    2014-10-01

    Full Text Available Catalytically active titanium dioxide is conventionally used as a white pigment for cosmetics, but undesirably induces a certain degree of decomposition of sebum on the skin on exposure to ultraviolet radiation in sunlight. In this work, titanium phosphates were prepared as a novel white pigment for cosmetics using titanium sulfate and phosphoric acid at various temperatures, with/without ultrasonic treatment. The chemical composition, powder properties, photocatalytic activity, color phase, moisture retention, and smoothness of the phosphates were evaluated. These titanium phosphates had less photocatalytic activity than titanium dioxide, which should be beneficial for protecting sebum on the skin. Samples prepared with ultrasonic treatment had lower visible light absorption than those not subjected to ultrasonication. The sample prepared at 40 °C with ultrasonic treatment had higher moisture retention capacity than those prepared under other conditions. Samples prepared at 40 °C had lower slipping resistance than samples prepared at 7 °C.

  6. Niobium phosphates as an intermediate temperature proton conducting electrolyte for fuel cells

    DEFF Research Database (Denmark)

    Huang, Yunjie; Li, Qingfeng; Jensen, Annemette Hindhede

    2012-01-01

    A new proton conductor based on niobium phosphates was synthesized using niobium pentoxide and phosphoric acid as precursors. The existence of hydroxyl groups in the phosphates was confirmed and found to be preserved after heat treatment at 500 °C or higher, contributing to an anhydrous proton...... conductivity of 1.6 × 10−2 S cm−1 at 250 °C. The conductivity increased with water content in the atmosphere and reached 5.8 × 10−2 S cm−1 under pure water vapour at the same temperature. The conductivity showed good stability in the low water partial pressure range of up to 0.05 atm. The metal phosphates...

  7. Efficacy of the biomaterials 3wt%-nanostrontium-hydroxyapatite-enhanced calcium phosphate cement (nanoSr-CPC) and nanoSr-CPC-incorporated simvastatin-loaded poly(lactic-co-glycolic-acid) microspheres in osteogenesis improvement: An explorative multi-phase experimental in vitro/vivo study.

    Science.gov (United States)

    Masaeli, Reza; Jafarzadeh Kashi, Tahereh Sadat; Dinarvand, Rassoul; Rakhshan, Vahid; Shahoon, Hossein; Hooshmand, Behzad; Mashhadi Abbas, Fatemeh; Raz, Majid; Rajabnejad, Alireza; Eslami, Hossein; Khoshroo, Kimia; Tahriri, Mohammadreza; Tayebi, Lobat

    2016-12-01

    The purpose of this multi-phase explorative in vivo animal/surgical and in vitro multi-test experimental study was to (1) create a 3wt%-nanostrontium hydroxyapatite-enhanced calcium phosphate cement (Sr-HA/CPC) for increasing bone formation and (2) creating a simvastatin-loaded poly(lactic-co-glycolic acid) (SIM-loaded PLGA) microspheres plus CPC composite (SIM-loaded PLGA+nanostrontium-CPC). The third goal was the extensive assessment of multiple in vitro and in vivo characteristics of the above experimental explorative products in vitro and in vivo (animal and surgical studies). Physical and chemical properties of the prepared Sr-HA/CPC were evaluated. MTT assay and alkaline phosphatase activities, and radiological and histological examinations of Sr-HA/CPC, CPC and negative control were compared. X-ray diffraction (XRD) indicated that crystallinity of the prepared cement increased by increasing the powder-to-liquid ratio. Incorporation of Sr-HA into CPC increased MTT assay (biocompatibility) and ALP activity (P<0.05). Histomorphometry showed greater bone formation after 4weeks, after implantation of Sr-HA/CPC in 10 rats compared to implantations of CPC or empty defects in the same rats (n=30, ANOVA P<0.05). METHODS AND RESULTS PERTAINING TO SIM-LOADED PLGA MICROSPHERES+NANOSTRONTIUM-CPC COMPOSITE: After SEM assessment, the produced composite of microspheres and enhanced CPC were implanted for 8weeks in 10 rabbits, along with positive and negative controls, enhanced CPC, and enhanced CPC plus SIM (n=50). In the control group, only a small amount of bone had been regenerated (localized at the boundary of the defect); whereas, other groups showed new bone formation within and around the materials. A significant difference was found in the osteogenesis induced by the groups sham control (16.96±1.01), bone materials (32.28±4.03), nanostrontium-CPC (24.84±2.6), nanostrontium-CPC-simvastatin (40.12±3.29), and SIM-loaded PLGA+nanostrontium-CPC (44.8±6.45) (ANOVA P

  8. phenylenediamine zinc(ii) phosphate

    African Journals Online (AJOL)

    PROF EKWUEME

    Zn2+ ions yielded a metallo-ligand of composition [ZnL2Ph(NH3)2(H2O)2] I. Compound I melts at 126oC and is soluble in common organic solvents such as ... H3PO4 and 0.137g of p-amino benzoic acid under vigorous stirring. The stirring ... low melting point of 126oC while compound II was thermally stable up to 3000C.

  9. Role of Phosphate Transport System Component PstB1 in Phosphate Internalization by Nostoc punctiforme.

    Science.gov (United States)

    Hudek, L; Premachandra, D; Webster, W A J; Bräu, L

    2016-11-01

    In bacteria, limited phosphate availability promotes the synthesis of active uptake systems, such as the Pst phosphate transport system. To understand the mechanisms that facilitate phosphate accumulation in the cyanobacterium Nostoc punctiforme, phosphate transport systems were identified, revealing a redundancy of Pst phosphate uptake systems that exists across three distinct operons. Four separate PstB system components were identified. pstB1 was determined to be a suitable target for creating phenotypic mutations that could result in the accumulation of excessive levels of phosphate through its overexpression or in a reduction of the capacity to accumulate phosphate through its deletion. Using quantitative real-time PCR (qPCR), it was determined that pstB1 mRNA levels increased significantly over 64 h in cells cultured in 0 mM added phosphate and decreased significantly in cells exposed to high (12.8 mM) phosphate concentrations compared to the level in cells cultured under normal (0.8 mM) conditions. Possible compensation for the loss of PstB1 was observed when pstB2, pstB3, and pstB4 mRNA levels increased, particularly in cells starved of phosphate. The overexpression of pstB1 increased phosphate uptake by N. punctiforme and was shown to functionally complement the loss of PstB in E. coli PstB knockout (PstB-) mutants. The knockout of pstB1 in N. punctiforme did not have a significant effect on cellular phosphate accumulation or growth for the most part, which is attributed to the compensation for the loss of PstB1 by alterations in the pstB2, pstB3, and pstB4 mRNA levels. This study provides novel in vivo evidence that PstB1 plays a functional role in phosphate uptake in N. punctiforme IMPORTANCE: Cyanobacteria have been evolving over 3.5 billion years and have become highly adept at growing under limiting nutrient levels. Phosphate is crucial for the survival and prosperity of all organisms. In bacteria, limited phosphate availability promotes the synthesis

  10. Inadequate awareness among chronic kidney disease patients regarding food and drinks containing artificially added phosphate.

    Directory of Open Access Journals (Sweden)

    Yoshiko Shutto

    Full Text Available Hyperphosphatemia is an important determinant of morbidity and mortality in patients with chronic kidney disease (CKD. Patients with CKD are advised to consume a low phosphate diet and are often prescribed phosphate-lowering drug therapy. However, commercially processed food and drinks often contain phosphate compounds, but the phosphate level is not usually provided in the ingredient list, which makes it difficult for CKD patients to choose a correct diet. We conducted a survey of the awareness of food/beverages containing artificially added phosphate among CKD patients undergoing hemodialysis. The subjects were 153 patients (77 males and 76 females; average age 56±11 years who were randomly selected from the Dialysis Center of Hirosaki City, Japan. The subjects were provided with a list of questions. The survey results showed that 93% of the subjects were aware of the presence of high sugar content in soda, whereas only 25% were aware of the presence of phosphate (phosphoric acid in such drinks. Despite 78% of the subjects being aware of the detrimental effects of consumption of a high phosphate diet, 43% drank at least 1 to 5 cans of soda per week and about 17% consumed "fast food" once each week. We also assessed the immediate effects of high-phosphate containing carbonated soda consumption by determining urinary calcium, phosphate, protein and sugar contents in overnight fasted healthy volunteers (n = 55; average age 20.7±0.3 years old, 20 males and 35 females. Significantly higher urinary calcium (adjusted using urinary creatinine excretion was found 2 h after consuming 350 ml of carbonated soda compared to the fasting baseline level (0.15±0.01 vs. 0.09±0.01, p = 0.001. Our survey results suggest that CKD patients undergoing hemodialysis are not adequately aware of the hidden source of phosphate in their diet, and emphasize the need for educational initiatives to raise awareness of this issue among CKD patients.

  11. Simulation of phosphate leaching in catchments with phosphate-saturated soils in the Netherlands

    NARCIS (Netherlands)

    Groenenberg, J.E.; Reinds, G.J.; Breeuwsma, A.

    1996-01-01

    The effects on phosphate leaching to surface waters of two scenarios for net phosphate input to sandy agricultural soils were estimated. WATBAL and ANIMO simulations for manure surplus areas in the Netherlands were used. The methodology and models were verified by comparing model results with

  12. Translocation of metal phosphate via the phosphate inorganic transport system of Escherichia coli

    NARCIS (Netherlands)

    van Veen, H.W; Abee, T.; Kortstee, G.J J; Konings, W.N; Zehnder, A.J B

    1994-01-01

    P-i transport via the phosphate inorganic transport system (Pit) of Escherichia coil was studied in natural and artificial membranes. P-i uptake via Pit is dependent on the presence of divalent cations, like Mg2+, Ca2+, Co2+, or Mn2+, which form a soluble, neutral metal phosphate (MeHPO(4)) complex.

  13. MAGNESIUM MONO POTASSIUM PHOSPHATE GROUT FOR P-REACTOR VESSEL IN-SITU DECOMISSIONING

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Stefanko, D.

    2011-01-05

    The objective of this report is to document laboratory testing of magnesium mono potassium phosphate grouts for P-Reactor vessel in-situ decommissioning. Magnesium mono potassium phosphate cement-based grout was identified as candidate material for filling (physically stabilizing) the 105-P Reactor vessel (RV) because it is less alkaline than portland cement-based grout (pH of about 12.4). A less alkaline material ({<=} 10.5) was desired to address a potential materials compatibility issue caused by corrosion of aluminum metal in highly alkaline environments such as that encountered in portland cement grouts. Information concerning access points into the P-Reactor vessel and amount of aluminum metal in the vessel is provided elsewhere. Fresh and cured properties were measured for: (1) commercially blended magnesium mono potassium phosphate packaged grouts, (2) commercially available binders blended with inert fillers at SRNL, (3) grouts prepared from technical grade MgO and KH{sub 2}PO{sub 4} and inert fillers (quartz sands, Class F fly ash), and (4) Ceramicrete{reg_sign} magnesium mono potassium phosphate-based grouts prepared at Argonne National Laboratory. Boric acid was evaluated as a set retarder in the magnesium mono potassium phosphate mixes.

  14. The biosensor based on the pyruvate oxidase modified conducting polymer for phosphate ions determinations.

    Science.gov (United States)

    Rahman, Md Aminur; Park, Deog-Su; Chang, Seung-Cheol; McNeil, Calum J; Shim, Yoon-Bo

    2006-01-15

    An enzymatic biosensor was fabricated by the covalent immobilization of pyruvate oxidase (PyO) onto the nano-particle comprised poly-5,2':5',2''-terthiophene-3'-carboxylic acid, poly-TTCA (nano-CP) layers on a glassy carbon electrode (GCE) for the amperometric detection of the phosphate ions. The direct electron transfer reaction of the immobilized PyO onto the nano-CP layers was investigated and the electron transfer rate constant was determined to be 0.65 s(-1). The electrochemically prepared nano-CP lowered the oxidation potential (+0.40 V versus Ag/AgCl) of an enzymatically generated H(2)O(2) by PyO in a phosphate solution. Experimental parameters affecting the sensitivity of the biosensors, such as amounts of the cofactors, the pH, the applied potential, and the temperature were optimized. A linear response for the detection of the phosphate ion was observed between 1.0 microM and 100 microM and the detection limit was determined to be about 0.3 microM. The response time of the biosensors was about 6s. The biosensor showed good selectivity towards other interfering anions. The long-term storage stability of the phosphate biosensor was studied and the sensor was applied in a human serum sample for the phosphate ions detection.

  15. EFFECTS OF SODIUM PHOSPHATE LOADING ON AEROBIC POWER AND CAPACITY IN OFF ROAD CYCLISTS

    Directory of Open Access Journals (Sweden)

    Scott Woska

    2009-12-01

    Full Text Available The main aim of this paper was to evaluate the effects of short- term (6 days phosphate loading, as well as prolonged (21 days intake of sodium phosphate on aerobic capacity in off-road cyclists. Nineteen well-trained cyclists were randomly divided into a supplemental (S and control group (C. Group S was supplemented for 6 days with tri-sodium phosphate, in a dose of 50 mg·kg-1 of FFM/d, while a placebo was provided for the C group. Additionally, group S was further subjected to a 3-week supplementation of 25 mg·kg-1 FFM/d, while group C received 2g of glucose. The results indicate a significant (p < 0.05 increase in VO2max, VEmax, and O2/HR, due to sodium phosphate intake over 6 days. Also a significant (p < 0.05 decrease in HRrest and HRmax occurred. The supplementation procedure caused a significant increase (p < 0.05 in Pmax and a shift of VAT towards higher loads. There were no significant changes in the concentration of 2,3-DPG, acid-base balance and lactate concentration, due to phosphate salt intake

  16. High-Strength / High Alkaline Resistant Fe-Phosphate Glass Fibers as Concrete Reinforcement

    Energy Technology Data Exchange (ETDEWEB)

    Mariano Velez

    2008-03-31

    Calcium-iron-phosphate glasses were developed whose chemical durabilities in alkaline solutions (pH 13) were comparable or superior to those of commercial alkaline-resistant (AR) silica-based glasses. However, the tensile strength of Ca-Fe-phosphate fibers, after being exposed to alkaline environments, including wet Portland cement pastes, is lower than that of current AR silicate fibers. Another series of Ca-Fe-phosphate glasses were developed with excellent chemical durability in strong acidic solutions (H2SO4, HF), indicating potential applications where silica-based fibers degrade very quickly, including E-glass. The new Ca-Fe-phosphate glasses can be melted and processed 300 to 500°C lower than silica-based glasses. This offers the possibility of manufacturing glass fibers with lower energy costs by 40-60% and the potential to reduce manufacturing waste and lower gas emissions. It was found that Ca-Fe-phosphate melts can be continuously pulled into fibers depending on the slope of the viscosity-temperature curve and with viscosity ~100 poise, using multi-hole Pt/Rh bushings.

  17. Phosphatation of zeolite H-ZSM-5: a combined microscopy and spectroscopy study.

    Science.gov (United States)

    van der Bij, Hendrik E; Aramburo, Luis R; Arstad, Bjørnar; Dynes, James J; Wang, Jian; Weckhuysen, Bert M

    2014-02-03

    A variety of phosphated zeolite H-ZSM-5 samples are investigated by using a combination of Fourier transfer infrared (FTIR) spectroscopy, single pulse (27)Al, (29)Si, (31)P, (1)H-(31)P cross polarization (CP), (27)Al-(31)P CP, and (27)Al 3Q magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy, scanning transmission X-ray microscopy (STXM) and N2 physisorption. This approach leads to insights into the physicochemical processes that take place during phosphatation. Direct phosphatation of H-ZSM-5 promotes zeolite aggregation, as phosphorus does not penetrate deep into the zeolite material and is mostly found on and close to the outer surface of the zeolite, acting as a glue. Phosphatation of pre-steamed H-ZSM-5 gives rise to the formation of a crystalline tridymite AlPO4 phase, which is found in the mesopores of dealuminated H-ZSM-5. Framework aluminum species interacting with phosphorus are not affected by hydrothermal treatment. Dealuminated H-ZSM-5, containing AlPO4 , retains relatively more framework Al atoms and acid sites during hydrothermal treatment than directly phosphated H-ZSM-5. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Determination of phosphate in soil extracts in the field: A green chemistry enzymatic method.

    Science.gov (United States)

    Campbell, Ellen R; Warsko, Kayla; Davidson, Anna-Marie; Bill Campbell, Wilbur H

    2015-01-01

    Measurement of ortho-phosphate in soil extracts usually involves sending dried samples of soil to a laboratory for analysis and waiting several weeks for the results. Phosphate determination methods often involve use of strong acids, heavy metals, and organic dyes. To overcome limitations of this approach, we have developed a phosphate determination method which can be carried out in the field to obtain results on the spot. This new method uses: •Small volumes.•An enzymatic reaction.•Green chemistry. First, the soil sample is extracted with deionized water and filtered. Next, an aliquot of the soil extract (0.5 mL) is transferred to a disposable cuvette, containing 0.5 mL of reaction mixture [200 mM HEPES, pH 7.6, 20 mM MgCl2, with 80 nmol 2-amino-6-mercapto-7-methylpurine ribonucleoside (MESG) and 1 unit of recombinant purine nucleoside phosphorylase (PNP; EC 2.4.2.1)], mixed, and incubated for 10 min at field temperature. Absorbance of the completed reaction is measured at 360 nm in open-source, portable photometer linked by bluetooth to a smartphone. The phosphate and phosphorus content of the soil is determined by comparison of its absorbance at 360 nm to a previously prepared standard phosphate curve, which is stored in the smartphone app.

  19. Effect of strontium ions substitution on gene delivery related properties of calcium phosphate nanoparticles.

    Science.gov (United States)

    Hanifi, A; Fathi, M H; Mir Mohammad Sadeghi, H