Metals concentration in phosphogypsum and phosphate fertilizers produced in Brazil using INAA

International Nuclear Information System (INIS)

Le Bourlegat, Fernanda M.; Saueia, Catia H.R.; Mazzilli, Barbara P.; Favaro, Deborah I.T.

2009-01-01

Phosphogypsum is obtained by wet reaction of the igneous phosphate rock with concentrated sulphuric acid, giving as final product phosphoric acid and dihydrated calcium sulphate (CaSO 4 .2H 2 O) as by-product. It may contain high quantities of P 2 O 5 , trace metals and radionuclides of U and Th series. Phosphogypsum worldwide production on 2006 was estimated in 170 million tons. All the countries that produce phosphate fertilizers by wet process are facing the same problem of finding solutions for the safe application of phosphogypsum, in order to minimize the impact caused by the disposal of large amounts of this by-product. Phosphogypsum can be used in agriculture as a soil amendment; however, for its safe application the concentration of the impurities present and their behaviour in the environment should be better understood. The radiological characterization has been extensively studied in the last decade, but there are few studies about the metals concentration in phosphogypsum. This work intends to determine the concentration of metals (Ba, Co, Cr, Fe, Hf, Na, Sc, Ta, Th, U, Zn e Zr) and rare earth elements (REE) present in phosphogypsum produced in Brazil and to compare the results with those found in the phosphate fertilizers commonly commercialized. The technique used for the determination of the metals was instrumental neutron activation analysis (INAA). (author)

25-hydroxyvitamin D, autoantigenic and total antibody concentrations

DEFF Research Database (Denmark)

Thorsen, Steffen Ullitz; Pipper, Christian B; Johannesen, Jesper

2018-01-01

conducted within this field. OBJECTIVE: Our objective was to investigate if higher 25-hydroxyvitamin D (25(OH)D) concentrations were inversely associated with β-cell autoantigens glutamic acid decarboxylase (isoform 65) (GADA) and insulinoma associated antigen-2A (IA-2A). Further, we also wanted to examine......BACKGROUND: B cells have recently entered the stage as an important accessory player in type 1 diabetes (T1D) etiopathogenesis. Experimental studies suggest regulatory functions of vitamin D on B cells. However, only a few human studies, with considerable methodological limitations, have been...... the relationship between 25(OH)D and total antibody concentrations. METHODS: We randomly selected 500 patients with newly diagnosed T1D and 500 siblings for 25(OH)D, antibody and genetic analysis from the population-based Danish Registry of Childhood and Adolescent Diabetes. The relative change (RC) in the mean...

Serum concentrations of antibodies against vaccine toxoids in children exposed perinatally to immunotoxicants

DEFF Research Database (Denmark)

Heilmann, Carsten; Budtz-Jørgensen, Esben; Nielsen, Flemming

2010-01-01

-2001, children were invited for examination with assessment of serum antibody concentrations at 5 years (before and after a booster vaccination) and at 7 years of age. Total PCB concentrations were determined in serum from ages 5 and 7 years, and data were also available on PCB concentrations in maternal...... pregnancy serum, maternal milk, and, for a subgroup, the child's serum at 18 months of age. RESULTS: A total of 587 children participated in the examinations at ages 5 and/or 7 years. At age 5 years, before the booster vaccination, the antidiphtheria antibody concentration was inversely associated with PCB......BACKGROUND: Polychlorinated biphenyls (PCBs) may cause immunotoxic effects, but the detailed dose-response relationship and possible vulnerable time windows of exposure are uncertain. In this study we applied serum concentrations of specific antibodies against childhood vaccines as sentinels...

Formation of calcium phosphates by vapour diffusion in highly concentrated ionic micro-droplets

Energy Technology Data Exchange (ETDEWEB)

Iafisco, M. [Alma Mater Studiorum Universita di Bologna, Dipartimento di Chimica ' ' G. Ciamician' ' , Via Selmi 2, 40126 Bologna (Italy); Universita del Piemonte Orientale, Dipartimento di Scienze Mediche, Via Solaroli 4, 28100 Novara (Italy); Delgado-Lopez, J.M.; Gomez-Morales, J.; Hernandez-Hernandez, M.A.; Rodriguez-Ruiz, I. [Laboratorio de Estudios Cristalograficos, IACT CSIC-UGR, Edificio Lopez Neyra, Avenida del Conocimiento, s/n 18100 Armilla (Spain); Roveri, N. [Alma Mater Studiorum Universita di Bologna, Dipartimento di Chimica ' ' G. Ciamician' ' , Via Selmi 2, 40126 Bologna (Italy)

2011-08-15

In this work we have used the sitting drop vapour diffusion technique, employing the ''crystallization mushroom '' to analyze the evolution of calcium phosphate crystallization in micro-droplets containing high initial concentrations of Ca{sup 2+} and HPO{sub 4}{sup 2-}. The decomposition of NH{sub 4}HCO{sub 3} solution produces vapours of NH{sub 3} and CO{sub 2} which diffuse through the droplets containing an aqueous solution of Ca(CH{sub 3}COO){sub 2} and (NH{sub 4}){sub 2}HPO{sub 4}. The result is the increase of pH by means of the diffusion of NH{sub 3} gas and the doping of the calcium phosphate with CO{sub 3}{sup 2-} ions by means of the diffusion of CO{sub 2} gas. The pH of the crystallization process is monitored and the precipitates at different times are characterized by XRD, FTIR, TGA, SEM and TEM techniques. The slow increase of pH and the high concentration of Ca{sup 2+} and HPO{sub 4}{sup 2-} in the droplets induce the crystallization of three calcium phosphate phases: dicalcium phosphate dihydrate (DCPD, brushite), octacalcium phosphate (OCP) and carbonate-hydroxyapatite (HA). The amount of HA nanocrystals with needle-like morphology and dimensions of about 100 nm, closely resembling the inorganic phase of bones, gradually increases, with the precipitation time up to 7 days, whereas the amount of DCPD, growing along the b axis, increases up to 3 days. Then, DCDP crystals start to hydrolyze yielding OCP nanoribbons and HA nanocrystals. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Radioimmunoassay for quantification of anti-tuberculin antibody concentration in guinea pig sera

Energy Technology Data Exchange (ETDEWEB)

Mauch, H [Universitaet des Saarlandes, Homburg/Saar (Germany, F.R.). Medizinische Klinik und Poliklinik; Kuemel, G [Universitaet des Saarlandes, Homburg/Saar (Germany, F.R.). Virologische Abt.

1978-04-01

A well suited model system for the study of the role of antibodies in immunoregulation is the BCG-infected guinea pig. The assessment of a detailed analysis of the antibody kinetics after BCG infection in comparison to the kinetics of cell-mediated immunity by the delayed type hypersensitivity reaction requires that a specially sensitive, reproducible and precise assay for the determination of antibody concentration is at hand. The methods hitherto available do not meet these requirements. There was developed an indirect double antibody solid phase radioimmunoassay for that purpose.

The preparation and certification of a South African phosphate concentrate for use as a reference material

International Nuclear Information System (INIS)

Hansen, R.G.

1985-01-01

This report describes the preparation, analysis, and certification of South African Reference Material (SARM) 32. The material is a phosphate concentrate from the Phalaborwa deposit, and was supplied by the Phosphate Development Corporation Ltd (Foskor). Eighteen laboratories in eight countries used a variety of analytical techniques to provide the analytical results

CALCIUM, CREATININE AND URINARY PHOSPHATE/CREATININE RATIO CONCENTRATIONS IN NEONATES OF VARIOUS GESTATIONAL AGES

Directory of Open Access Journals (Sweden)

O. I. Fomina

2014-01-01

Full Text Available Objective: specify peculiarities of calcium and phosphates excretion in neonates of various gestational ages and types of feeding in neonatal period. Patients and methods. Calcium-creatinine (Ca/Cr and phosphate-creatinine (P/Cr ratio concentrations were determined in 96 healthy neonates of 38-40 weeks of gestational age and 146 premature infants of 28-37 weeks of gestational age of various types of feeding. Results. The Ca/Cr ratio concentration in healthy term infants in the early neonatal period amounted to 0.9-2.2 (median – 1.8, the P/Cr ratio concentration – 0.8-2.1 (median – 1.6. The Ca/Cr ratio concentration in premature infants (28-37 weeks of gestational age amounted to 0.9-2.4 (median – 1.9, which is comparable to this parameter’s value in term infants. The P/Cr ratio concentration amounted to 0.7-3.1 (median – 2.4, which exceeds this parameter’s value in term infants. The lesser the gestational age and birth weight, the higher the Ca/Cr and P/Cr ratio concentrations. The authors revealed hypercalciuria and hyperphosphaturia in premature infants with a very low body weight fed with specialized formulas. Conclusions. Use of specialized formulas in small premature infants (gestational age < 33 weeks with VLBW results in excessive calcium and phosphates excretion. It is reasonable to monitor their concentrations using a non-invasive and informative method of determining Ca/Cr and P/Cr ratios. Feeding of premature infants with BW > 1,500 g with breast milk only (in case of the mother’s adequate lactation allows avoiding hypercalciuria and hyperphosphaturia and preventing risk of a renal pathology. 

In silico peptide prediction for antibody generation to recognize 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) in genetically modified organisms.

Science.gov (United States)

Marani, Mariela M; Costa, Joana; Mafra, Isabel; Oliveira, Maria Beatriz P P; Camperi, Silvia A; Leite, José Roberto de Souza Almeida

2015-03-01

For the prospective immunorecognition of 5-enolpyruvylshikimate-3-phosphate synthase (CP4-EPSPS) as a biomarker protein expressed by transgenic soybean, an extensive in silico evaluation of the referred protein was performed. The main objective of this study was the selection of a set of peptides that could function as potential immunogens for the production of novel antibodies against CP4-EPSPS protein. For this purpose, the protein was in silico cleaved with trypsin/chymotrypsin and the resultant peptides were extensively analyzed for further selection of the best candidates for antibody production. The analysis enabled the successful proposal of four peptides with potential immunogenicity for their future use as screening biomarkers of genetically modified organisms. To our knowledge, this is the first attempt to select and define potential linear epitopes for the immunization of animals and, subsequently, to generate adequate antibodies for CP4-EPSPS recognition. The present work will be followed by the synthesis of the candidate peptides to be incubated in animals for antibody generation and potential applicability for the development of an immunosensor for CP4-EPSPS detection. © 2015 Wiley Periodicals, Inc.

[Influence of an infusion of 5- or 20% glucose solution on blood glucose and inorganic phosphate concentrations in dairy cows].

Science.gov (United States)

Aldaek, T A A; Failing, K; Wehrend, A; Klymiuk, M C

2011-01-01

The study was performed to evaluate the influence of an intravenous infusion of 5% and 20% dextrose solution on the plasma concentration of glucose and inorganic phosphate in healthy, dairy cows. Ten healthy, lactating, nonpregnant 3 to 6 year-old Holstein-Friesian cows were included in this investigation. The daily milk yield was 20.3±2.7 liters. Blood plasma concentrations of inorganic phosphate and glucose were determined before, during, immediately and 60 minutes after infusion of 0.9% physiological saline, 5% or 20% dextrose solution. A statistically significant influence of dextrose infusion on blood glucose concentration was observed. After 20% dextrose infusion (200 g dextrose) the blood glucose concentration increased by approximately 13.26 mmol/l. The administration of 5% dextrose solution (50 g dextrose) yielded an increase of blood glucose concentration by 3.31 mmol/l. There was no significant correlation between plasma inorganic phosphate concentrations and infusion of 0.9% saline, 5% or 20% dextrose solution. Intravenous administration of 1000 ml of 5% or 20% dextrose solution does not induce a lasting plasma phosphate reduction and is suitable for elevating the blood glucose concentration.

Calcium phosphate/chitosan composite coating: Effect of different concentrations of Mg2+ in the m-SBF on its bioactivity

International Nuclear Information System (INIS)

Zhang, Jie; Dai, Changsong; Wei, Jie; Wen, Zhaohui; Zhang, Shujuan; Lin, Lemin

2013-01-01

The purpose of this study was to investigate the effect of different concentration of Mg 2+ in a modified simulated body fluid (m-SBF) on the bioactivity of calcium phosphate/chitosan composite coating. Calcium phosphate/chitosan composite coating was prepared on graphite substrate via electrophoretic deposition (EPD) followed by conversion in a phosphate buffer solution (PBS). The obtained samples were soaked in the m-SBF containing different concentration of Mg 2+ for different times. And then, the composite coatings were assessed using X-ray diffractometer (XRD), Fourier-transformed infrared spectroscopy (FTIR), Raman spectra, and scanning electron microscope (SEM) with an energy dispersive spectrometer (EDS). The soaking solution was evaluated by inductively coupled plasma optical emission spectrometer (ICP-OES) test. The analytical results showed that hydroxyapatite (HA) and bone-like apatite (HCA) grew on the surface of calcium phosphate/chitosan composite coating after incubation in different m-SBF. With Mg 2+ concentration in m-SBF increased from 1× Mg to 10× Mg, HA in the composite coating first presented a dissolving process and then a precipitating one slowly, while HCA presented a growing trend, continuously. The increasing of Mg 2+ concentration in the m-SBF inhibited the total growing process of HA and HCA as a whole. The structure of the composite coating changed from spherical into irregular morphology with the concentration of Mg 2+ increasing from 1× Mg to 10× Mg. Over all, with the Mg 2+ concentration increasing, the bioactivity of calcium phosphate/chitosan composite coating tended to decrease.

Calcium phosphate/chitosan composite coating: Effect of different concentrations of Mg2+ in the m-SBF on its bioactivity

Science.gov (United States)

Zhang, Jie; Dai, Changsong; Wei, Jie; Wen, Zhaohui; Zhang, Shujuan; Lin, Lemin

2013-09-01

The purpose of this study was to investigate the effect of different concentration of Mg2+ in a modified simulated body fluid (m-SBF) on the bioactivity of calcium phosphate/chitosan composite coating. Calcium phosphate/chitosan composite coating was prepared on graphite substrate via electrophoretic deposition (EPD) followed by conversion in a phosphate buffer solution (PBS). The obtained samples were soaked in the m-SBF containing different concentration of Mg2+ for different times. And then, the composite coatings were assessed using X-ray diffractometer (XRD), Fourier-transformed infrared spectroscopy (FTIR), Raman spectra, and scanning electron microscope (SEM) with an energy dispersive spectrometer (EDS). The soaking solution was evaluated by inductively coupled plasma optical emission spectrometer (ICP-OES) test. The analytical results showed that hydroxyapatite (HA) and bone-like apatite (HCA) grew on the surface of calcium phosphate/chitosan composite coating after incubation in different m-SBF. With Mg2+ concentration in m-SBF increased from 1× Mg to 10× Mg, HA in the composite coating first presented a dissolving process and then a precipitating one slowly, while HCA presented a growing trend, continuously. The increasing of Mg2+ concentration in the m-SBF inhibited the total growing process of HA and HCA as a whole. The structure of the composite coating changed from spherical into irregular morphology with the concentration of Mg2+ increasing from 1× Mg to 10× Mg. Over all, with the Mg2+ concentration increasing, the bioactivity of calcium phosphate/chitosan composite coating tended to decrease.

Time-related Changes in pH, Buffering Capacity and Phosphate and Urea Concentration of Stimulated Saliva.

Science.gov (United States)

Vuletic, Lea; Peros, Kristina; Spalj, Stjepan; Rogic, Dunja; Alajbeg, Ivan

2014-01-01

To quantify changes in pH, buffering capacity and hydrogen carbonate, phosphate, protein and urea concentrations of stimulated saliva which occur during a 30-min measurement delay after saliva collection. The correlation between time-related chemical changes and changes of salivary pH and buffering capacity was assessed in order to explain the observed changes in salivary pH and buffering capacity. Stimulated saliva samples were collected from 30 volunteers after inducing salivation by chewing a piece of parafilm. Measurements of salivary variables were made immediately after saliva collection and again 30 min later, during which time the specimens were exposed to the atmosphere in collection cups at room temperature. Postponement of measurements resulted in a significant increase in pH and a significant decrease of buffering capacity, phosphate and urea concentration. The results suggest that the time-related pH increase could primarily be attributed to loss of dissolved carbon dioxide from saliva, and confirm the importance of hydrogen carbonate in the neutralisation of hydrogen ions, but they do not support the principle of catalysed phase-buffering for the hydrogen carbonate buffer system in saliva. A decrease in phosphate and urea concentration affects salivary buffering capacity. This study emphasises the importance of the standardisation of measurement time when measuring salivary pH, buffering capacity, phosphate and urea concentrations following the collection of saliva in order to obtain comparable results. It also provides a partial explanation of the mechanisms underlying the observed changes of pH and buffering capacity over time.

The conditions for uranium concentration in the phosphates of Tchivoula, Congo

International Nuclear Information System (INIS)

Giresse, P.; N'Landou, J. de Dieu; Wiber, M.

1986-01-01

The processes of deposition of marine phosphates in the Maastrichtian seas of the Congo do not appear capable alone of having produced the significant concentrations of uranium found. Diagenetic phenomena resulted in a mobilisation and a secondary concentration of uranium in the interior of recrystallized apatites. This secondary uranium may have been derived from the residual organic matrix in the deposit. Towards the top of the beds, hydrolysis of the apatites and authigenesis of crandallite, barrandite and ferruginous variscite led to uranium concentrations which are characteristic of alteration in a tropical climate. In contrast, wavellite, the final product of supergene alteration does not retain uranium. In the case of the Tchivoula deposits, the overlying Paleocene beds may have been the source of the uraniferous solutions' downslope movement which favored concentration in the underlying sediments. (orig.)

Removal of phosphate from solution by adsorption and precipitation of calcium phosphate onto monohydrocalcite.

Science.gov (United States)

Yagi, Shintaro; Fukushi, Keisuke

2012-10-15

The sorption behavior and mechanism of phosphate on monohydrocalcite (CaCO(3)·H(2)O: MHC) were examined using batch sorption experiments as a function of phosphate concentrations, ionic strengths, temperatures, and reaction times. The mode of PO(4) sorption is divisible into three processes depending on the phosphate loading. At low phosphate concentrations, phosphate is removed by coprecipitation of phosphate during the transformation of MHC to calcite. The sorption mode at the low-to-moderate phosphate concentrations is most likely an adsorption process because the sorption isotherm at the conditions can be fitted reasonably with the Langmuir equation. The rapid sorption kinetics at the conditions is also consistent with the adsorption reaction. The adsorption of phosphate on MHC depends strongly on ionic strength, but slightly on temperature. The maximum adsorption capacities of MHC obtained from the regression of the experimental data to the Langmuir equation are higher than those reported for stable calcium carbonate (calcite or aragonite) in any conditions. At high phosphate concentrations, the amount of sorption deviates from the Langmuir isotherm, which can fit the low-to-moderate phosphate concentrations. Speciation-saturation analyses of the reacted solutions at the conditions indicated that the solution compositions which deviate from the Langmuir equation are supersaturated with respect to a certain calcium phosphate. The obtained calcium phosphate is most likely amorphous calcium phosphate (Ca(3)(PO(4))(2)·xH(2)O). The formation of the calcium phosphate depends strongly on ionic strength, temperature, and reaction times. The solubility of MHC is higher than calcite and aragonite because of its metastability. Therefore, the higher solubility of MHC facilitates the formation of the calcium phosphates more than with calcite and aragonite. Copyright © 2012 Elsevier Inc. All rights reserved.

Serum Vaccine Antibody Concentrations in Adolescents Exposed to Perfluorinated Compounds

DEFF Research Database (Denmark)

Grandjean, Philippe; Heilmann, Carsten; Weihe, Pal

2017-01-01

BACKGROUND: Postnatal exposure to perfluorinated alkylate substances (PFASs) is associated with lower serum concentrations of specific antibodies against certain childhood vaccines at 7 y. OBJECTIVES: We prospectively followed a Faroese birth cohort to determine these associations at 13 y. METHOD...

Quality control of radiolabeled antibodies through simultaneous determination of antibody concentration and specific activity using time-resolved interaction analysis and reverse kinetic fit

International Nuclear Information System (INIS)

Andersson, K.; Mihaylova, D.; Wang, E.; Abrahamsen, L.; Buijs, J.; Bjoerkelund, H.

2015-01-01

Full text of publication follows. With the advent of efficient methods for producing proteins that bind to a defined target, the number of radiolabeled proteins, and in particular antibodies, used for medical imaging and cancer therapy is increasing rapidly. In line with this increase, focus should be put on methods for the quality control (QC). Proper antibody quality is of fundamental importance to guarantee safety and consistent efficacy for the patient. Adequate QC procedures exist for small radiolabeled synthetic compounds like FDG, but antibody based radiopharmaceuticals are different. Proteins are much more complex and fragile than the synthetic compounds, and hence require new methods for adequate characterization and QC. Yet another complication is the labeling where there is a risk that a subpopulation of the protein is damaged to the level that it no longer binds the target. Therefore, a new toolbox is required to fulfill the quality characterization of radiolabeled antibodies. We have developed a QC assay for the simultaneous determination of antibody function, concentration and specific activity. The assay is based on time-resolved detection of the antibody interaction with antigen-coated magnetic beads in LigandTracer instruments. The resulting binding curve is evaluated using reverse kinetic fits, where the known interaction parameters of the antibody-antigen interaction are set constant while as the concentration and signal level are fitted. The assay takes approximately 2 hours and the majority of the time constitutes automated data collection in the instrument. The QC assay has been tested on multiple antibody-antigen interactions and consistently provides repeatable results for concentration and specific activity, both with coefficient of variation (CV) less than 15%. We believe that this QC assay can improve the quality of radiolabeled therapeutic antibodies. (authors)

Validation of analytical method to calculate the concentration of conjugated monoclonal antibody; Validacao de metodo analitico para calculo de concentracao de anticorpo monoclonal conjugado

Energy Technology Data Exchange (ETDEWEB)

Alcarde, Lais F.; Massicano, Adriana V.F.; Oliveira, Ricardo S.; Araujo, Elaine B. de, E-mail: lais_alcarde@hotmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

The objective of this study was to develop a quantitative analytical method using high performance liquid chromatography (HPLC) to determine the antibody concentration in conjunction with bifunctional chelator. Assays were performed using a high performance liquid chromatograph, and the following conditions were used: flow rate of 1 mL / min, 15 min run time, 0.2 M sodium phosphate buffer pH 7.0 as the mobile phase and column of molecular exclusion BioSep SEC S-3000 (300 x 7.8 mm, 5 μM - Phenomenex). The calibration curve was obtained with AcM diluted in 0.2 M sodium phosphate buffer pH 7.0 by serial dilution, yielding the concentrations: 400 μg/mL, 200 μg/mL, 100 μg/mL, 50 μg/mL, 25 μg/mL and 12.5 μg/mL. From the calibration curve calculated the equation of the line and with it the concentration of the immunoconjugate. To ensure the validity of the method accuracy and precision studies were conducted. The accuracy test consisted in the evaluation of 3 samples of known concentration, being this test performed with low concentrations (50 μg/mL), medium (100 μg/mL) and high (200 μg/mL). The precision test consisted of 3 consecutive measurements of one sample of known concentration, subject to the conditions set forth above for the other tests. The correlation coefficient of the standard curve was greater than 97%, the accuracy was satisfactory at low concentrations as well as accuracy. The method was validated by showing it for the accurate and precise determination of the concentration of the immunoconjugate. Furthermore, this assay was found to be extremely important, because using the correct mass of the protein, the radiochemical purity of the radioimmunoconjugate was above 95% in all studies.

Calcium phosphate/chitosan composite coating: Effect of different concentrations of Mg{sup 2+} in the m-SBF on its bioactivity

Energy Technology Data Exchange (ETDEWEB)

Zhang, Jie [School of Chemistry Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Pharmacy College, Jiamusi University, Jiamusi 154007 (China); Dai, Changsong, E-mail: changsd@hit.edu.cn [School of Chemistry Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Wei, Jie [School of Chemistry Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); School of Chemistry and Bioengineering, Suzhou Science Technology University, Suzhou 215009 (China); Wen, Zhaohui, E-mail: wenzhaohui1968@163.com [Department of neuro intern, First Affiliated Hospital of Harbin Medical University, Harbin 150001 (China); Zhang, Shujuan; Lin, Lemin [Department of neuro intern, First Affiliated Hospital of Harbin Medical University, Harbin 150001 (China)

2013-09-01

The purpose of this study was to investigate the effect of different concentration of Mg{sup 2+} in a modified simulated body fluid (m-SBF) on the bioactivity of calcium phosphate/chitosan composite coating. Calcium phosphate/chitosan composite coating was prepared on graphite substrate via electrophoretic deposition (EPD) followed by conversion in a phosphate buffer solution (PBS). The obtained samples were soaked in the m-SBF containing different concentration of Mg{sup 2+} for different times. And then, the composite coatings were assessed using X-ray diffractometer (XRD), Fourier-transformed infrared spectroscopy (FTIR), Raman spectra, and scanning electron microscope (SEM) with an energy dispersive spectrometer (EDS). The soaking solution was evaluated by inductively coupled plasma optical emission spectrometer (ICP-OES) test. The analytical results showed that hydroxyapatite (HA) and bone-like apatite (HCA) grew on the surface of calcium phosphate/chitosan composite coating after incubation in different m-SBF. With Mg{sup 2+} concentration in m-SBF increased from 1× Mg to 10× Mg, HA in the composite coating first presented a dissolving process and then a precipitating one slowly, while HCA presented a growing trend, continuously. The increasing of Mg{sup 2+} concentration in the m-SBF inhibited the total growing process of HA and HCA as a whole. The structure of the composite coating changed from spherical into irregular morphology with the concentration of Mg{sup 2+} increasing from 1× Mg to 10× Mg. Over all, with the Mg{sup 2+} concentration increasing, the bioactivity of calcium phosphate/chitosan composite coating tended to decrease.

Phosphate concentration and arbuscular mycorrhizal colonisation influence the growth, yield and expression of twelve PHT1 family phosphate transporters in foxtail millet (Setaria italica.

Directory of Open Access Journals (Sweden)

S Antony Ceasar

Full Text Available Phosphorus (P is an essential element which plays several key roles in all living organisms. Setaria italica (foxtail millet is a model species for panacoid grasses including several millet species widely grown in arid regions of Asia and Africa, and for the bioenergy crop switchgrass. The growth responses of S. italica to different levels of inorganic phosphate (Pi and to colonisation with the arbuscular mycorrhizal fungus Funneliformis mosseae (syn. Glomus mosseae were studied. Phosphate is taken up from the environment by the PHT1 family of plant phosphate transporters, which have been well characterized in several plant species. Bioinformatic analysis identified 12 members of the PHT1 gene family (SiPHT1;1-1;12 in S. italica, and RT and qPCR analysis showed that most of these transporters displayed specific expression patterns with respect to tissue, phosphate status and arbuscular mycorrhizal colonisation. SiPHT1;2 was found to be expressed in all tissues and in all growth conditions tested. In contrast, expression of SiPHT1;4 was induced in roots after 15 days growth in hydroponic medium of low Pi concentration. Expression of SiPHT1;8 and SiPHT1;9 in roots was selectively induced by colonisation with F. mosseae. SiPHT1;3 and SiPHT1;4 were found to be predominantly expressed in leaf and root tissues respectively. Several other transporters were expressed in shoots and leaves during growth in low Pi concentrations. This study will form the basis for the further characterization of these transporters, with the long term goal of improving the phosphate use efficiency of foxtail millet.

Phosphate concentration and arbuscular mycorrhizal colonisation influence the growth, yield and expression of twelve PHT1 family phosphate transporters in foxtail millet (Setaria italica).

Science.gov (United States)

Ceasar, S Antony; Hodge, Angela; Baker, Alison; Baldwin, Stephen A

2014-01-01

Phosphorus (P) is an essential element which plays several key roles in all living organisms. Setaria italica (foxtail millet) is a model species for panacoid grasses including several millet species widely grown in arid regions of Asia and Africa, and for the bioenergy crop switchgrass. The growth responses of S. italica to different levels of inorganic phosphate (Pi) and to colonisation with the arbuscular mycorrhizal fungus Funneliformis mosseae (syn. Glomus mosseae) were studied. Phosphate is taken up from the environment by the PHT1 family of plant phosphate transporters, which have been well characterized in several plant species. Bioinformatic analysis identified 12 members of the PHT1 gene family (SiPHT1;1-1;12) in S. italica, and RT and qPCR analysis showed that most of these transporters displayed specific expression patterns with respect to tissue, phosphate status and arbuscular mycorrhizal colonisation. SiPHT1;2 was found to be expressed in all tissues and in all growth conditions tested. In contrast, expression of SiPHT1;4 was induced in roots after 15 days growth in hydroponic medium of low Pi concentration. Expression of SiPHT1;8 and SiPHT1;9 in roots was selectively induced by colonisation with F. mosseae. SiPHT1;3 and SiPHT1;4 were found to be predominantly expressed in leaf and root tissues respectively. Several other transporters were expressed in shoots and leaves during growth in low Pi concentrations. This study will form the basis for the further characterization of these transporters, with the long term goal of improving the phosphate use efficiency of foxtail millet.

Estimated exposures to perfluorinated compounds in infancy predict attenuated vaccine antibody concentrations at age 5-years.

Science.gov (United States)

Grandjean, Philippe; Heilmann, Carsten; Weihe, Pal; Nielsen, Flemming; Mogensen, Ulla B; Timmermann, Amalie; Budtz-Jørgensen, Esben

2017-12-01

Perfluorinated alkylate substances (PFASs) are highly persistent and may cause immunotoxic effects. PFAS-associated attenuated antibody responses to childhood vaccines may be affected by PFAS exposures during infancy, where breastfeeding adds to PFAS exposures. Of 490 members of a Faroese birth cohort, 275 and 349 participated in clinical examinations and provided blood samples at ages 18 months and 5 years. PFAS concentrations were measured at birth and at the clinical examinations. Using information on duration of breastfeeding, serum-PFAS concentration profiles during infancy were estimated. As outcomes, serum concentrations of antibodies against tetanus and diphtheria vaccines were determined at age 5. Data from a previous cohort born eight years earlier were available for pooled analyses. Pre-natal exposure showed inverse associations with the antibody concentrations five years later, with decreases by up to about 20% for each two-fold higher exposure, while associations for serum concentrations at ages 18 months and 5 years were weaker. Modeling of serum-PFAS concentration showed levels for age 18 months that were similar to those measured. Concentrations estimated for ages 3 and 6 months showed the strongest inverse associations with antibody concentrations at age 5 years, particularly for tetanus. Joint analyses showed statistically significant decreases in tetanus antibody concentrations by 19-29% at age 5 for each doubling of the PFAS exposure in early infancy. These findings support the notion that the developing adaptive immune system is particularly vulnerable to immunotoxicity during infancy. This vulnerability appears to be the greatest during the first 6 months after birth, where PFAS exposures are affected by breast-feeding.

Change in concentration of inorganic phosphate and phosphocreatine in the rat diaphragm under the influence of whole-body gamma irradiation

Energy Technology Data Exchange (ETDEWEB)

Mansour, M A; Gaber, M; Abdel-Fatah, K I

1987-01-01

The influence of irradiation on the concentration of creatine phosphate and inorganic phosphate in the diaphragm muscle were studied in rats exposed to 400 rad and 800 rad whole-body gamma radiation. The results showed that on the first day of post-exposure with 400 rad, the creatine phosphate concentration significantly increased, while the level significantly decreased on the third up to the fourteenth days of post exposure. In animals exposed to 800 rad, the diaphragm phosphocreatine showed a significant decrease on the first up to the ninth day post-irradiation as compared with the control group.

Change in concentration of inorganic phosphate and phosphocreatine in the rat diaphragm under the influence of whole-body gamma irradiation

International Nuclear Information System (INIS)

Mansour, M.A.; Gaber, M.; Abdel-Fatah, K.I.

1987-01-01

The influence of irradiation on the concentration of creatine phosphate and inorganic phosphate in the diaphragm muscle were studied in rats exposed to 400 rad and 800 rad whole-body gamma radiation. The results showed that on the first day of post-exposure with 400 rad, the creatine phosphate concentration significantly increased, while the level significantly decreased on the third up to the fourteenth days of post exposure. In animals exposed to 800 rad, the diaphragm phosphocreatine showed a significant decrease on the first up to the ninth day post-irradiation as compared with the control group

Continuous tests of Phosphoric Acid - dihydrate process - from phosphatic concentrate of Itataia-CE ore

International Nuclear Information System (INIS)

Santos Benedetto, J. dos.

1984-01-01

A consolidation of principal studies and continuous tests done with phosphatic concentrated of Itataia ore intending phosphoric acid production by humid-route dihydrate way process is presented. The production of phosphoric acid is applied in uranium extraction process by solvents. (author) [pt

Solubilities of some hydrous REE phosphates with implications for diagenesis and sea water concentrations

International Nuclear Information System (INIS)

Jonasson, R.G.; Bancroft, G.M.; Nesbitt, H.W.

1985-01-01

Solubility product determinations suggest that the hydrous phosphates of the rare earths, REPO 4 .xH 2 O, are important in controlling the sea water REE concentrations. Two of these solids, rhabdophane, (P6 2 22) and 'hydrous xenotime', (I4 1 /amd), have been synthesized at 100 C via the acid hydrolysis of the respective REE pyrophosphate. The solubility products at infinite dilution were determined to be pK 0 = 24.5, (La at 25 C); 26.0, (Pr at 100 C); 25.7, (Nd at 100 C); and 25.5, (Er at 100 C). On the basis of calculations involving the reaction of Re 3+ with apatite to form the hydrous phosphate, the lanthanum concentration in sea water is predicted to be about 140 pmol/L. Laboratory experiments support the hypothesis that apatite is a substrate for reactions with dissolved REE. (author)

LIPOPOLYSACCHARIDE INDUCES THE PRODUCTION OF DIAGNOSTIC MONOCLONAL ANTIBODY BY HYBRIDOMA CELLS AGAINST CONGENITAL ADRENAL HYPERPLASIA

Directory of Open Access Journals (Sweden)

GEK KEE CHUA

2017-11-01

Full Text Available The purpose of this research is to screen and identify the potential inducers in maximizing the production of monoclonal antibody by hybridoma 192 cell line for Congenital Adrenal Hyperplasia diagnostic. There are nine inducers used in this research, namely lysozyme, aldolase, sodium butyrate, sodium phosphate, potassium phosphate, dimethyl sulfoxide, lipopolysaccharide, essential amino acids, and nonessential amino acids. Hybridoma 192 cell was cultured in 5% CO2 incubator at 37°C and ˃80% humidity in the medium with different concentrations of inducer agents. The inducers were added at the beginning of the culture and the samples were taken after 72 h of culture. The performance of these inducer agents was assessed based on the maximum monoclonal antibody titer achieved using Enzyme-linked Immunosorbent Assay. Lipopolysaccharide was found to increase the maximum monoclonal antibody titer when supplemented at 8 to 12 µg/mL. After optimization using one-factor central composite design at this range, the optimum point was determined to be 8 µg/mL. Verification experiments shows that lipopolysaccharide enhanced the average specific monoclonal antibody production rate by 56% relative to control. In conclusion, lipopolysaccharide at 8 µg/mL is able to increase the monoclonal antibody specific production of hybridoma 192 cell line.

Liver/kidney microsomal antibody type 1 and liver cytosol antibody type 1 concentrations in type 2 autoimmune hepatitis

OpenAIRE

Muratori, L; Cataleta, M; Muratori, P; Lenzi, M; Bianchi, F

1998-01-01

Background—Liver/kidney microsomal antibody type 1 (LKM1) and liver cytosol antibody type 1 (LC1) are the serological markers of type 2 autoimmune hepatitis (AIH). 
Aims—Since LKM1 and LC1 react against two distinct liver specific autoantigens (cytochrome P450IID6 (CYP2D6) and a 58 kDa cytosolic polypeptide respectively), the aim was to see whether LKM1 and LC1 concentrations correlate with liver disease activity. 
Patients—Twenty one patients with type 2 AIH were studied. 
Methods—A...

Beneficial phosphate recovery from reverse osmosis (RO) concentrate of an integrated membrane system using polymeric ligand exchanger (PLE).

Science.gov (United States)

Kumar, Manish; Badruzzaman, Mohammad; Adham, Samer; Oppenheimer, Joan

2007-05-01

Phosphorus (P) discharge to surface water is a major environmental problem. Wastewater treatment is targeted towards removal of this nutrient to prevent degradation of surface water. Integrated membrane systems (IMS) are increasingly being considered for wastewater reclamation, and provide excellent removal of P compounds. However, reverse osmosis (RO), which forms an integral part of these IMSs, concentrates most dissolved substances including P-species such as phosphates in the RO waste stream. In this study, removal of phosphate from this stream using polymeric ligand exchange (PLE) resins was investigated. Further, the possibility of phosphate recovery through struvite (MgNH(4)PO(4).6H(2)O) precipitation was tested. Struvite has been promoted as a slow release fertilizer in recent years. This study demonstrates that PLEs can be successfully used to remove phosphate from RO-concentrate, and to recover more than 85% of the adsorbed phosphorus from the exhausted media and precipitated as a beneficial product (struvite). The approach, presented in this study, suggests advantages of providing economic benefit from a waste product (RO) while avoiding phosphorus discharge to the environment.

Immune response to pneumococcal polysaccharides 4 and 14 in elderly and young adults. I Antibody concentrations, avidity and functional activity

Directory of Open Access Journals (Sweden)

Carlone George M

2005-06-01

Full Text Available Abstract Streptococcus pneumoniae is a serious worldwide pathogen and the focus of numerous vaccine development projects. Currently the most widely accepted surrogate marker for evaluating the efficacy of a given vaccine is to utilize ELISA. Measurement of antibody concentration by ELISA without reduction in cross-reactive antibodies causes an overestimation of antibody concentration and therefore protection, this is most notable in the aged, an at risk group for this infection. We compared the immune response to the pneumococcal polysaccharides (PPS 4 and 14 of 20 young to 20 elderly adults. Pre-and post-vaccination IgG antibody concentrations and antibody avidity against PPS4 and PPS14 were measured using two different enzyme-linked immunosorbant assay (ELISA absorption protocols. All sera were pre-absorbed with either cell-wall polysaccharide (CPS, or CPS and serotype 22F polysaccharide. Pre- and post-vaccination IgG antibody concentrations for serotype 4, but not 14, were significantly lowered with the additional absorption with serotype 22F polysaccharide in both age groups. Young and elderly demonstrated a significant increase from pre- to post-immunization antibody concentration, using either absorption method; and opsonophagocytic antibody titers in response to both PPS4 and PPS14. The correlation coefficients between ELISA and opsonophagocytic assays were improved by additional absorption with serotype 22F in response to serotype 4, but not serotype 14 in all age groups. Opsonophagocytic antibody titers in a sub-group of elderly (>77 years of age were significantly lower than the opsonophagocytic antibody concentrations in young adults. These results suggest the importance of eliminating cross-reactive antibodies from ELISA measurements by absorption of serum and an age-related impairment in the antibody response to pneumococcal polysaccharides.

Radioactivity of phosphate ores from Karatas-Mazidag phosphate deposit of Turkey

International Nuclear Information System (INIS)

Akyuez, T.; Varinlioglu, A.; Kose, A.; Akyuez, S.

2000-01-01

The specific activities of 238 U, 226 Ra, 232 Th and 40 K in the composite samples of phosphate ores of type I (grey-coloured ore, with high P 2 O 5 (21-35%) and low calcite content) and of type II (grey coloured calcite ore, with low P 2 O 5 content (5-17%)) of Karatas-Mazidag phosphate deposit, Turkey, have been determined by gamma spectrometry together with phosphatic animal feed ingredients. The concentrations of 238 U, 226 Ra, 232 Th and 40 K were found to be up to 557, 625, 26 and 297 Bq x kg -1 , respectively. Radium equivalent activities of samples were calculated and compared with those given in the literature. Uranium concentration of the individual phosphate samples, from which composite samples of ores of type I and II have been prepared, were found to show and increasing trend with increasing P 2 O 5 and F concentrations. (author)

Phase evolution and photoluminescence enhancement of CePO4 nanowires from a low phosphate concentration system

International Nuclear Information System (INIS)

Xu Pengfei; Yu Ranbo; Zong Lingbo; Wang Jiali; Wang Dan; Deng Jinxia; Chen Jun; Xing Xianran

2013-01-01

Uniform CePO 4 nanowires have been successfully synthesized in a low phosphate concentration system through a single-step hydrothermal process. The low phosphate concentration might decrease the surface PO 4 3− adsorption of the as-synthesized CePO 4 nanowires efficiently and benefit their photoluminescence. The CePO 4 nanowires were identified to go through phase evolution from pure monoclinic to mixed hexagonal and monoclinic phase by only increasing the initial molar ratio of cerium and phosphate source (denoted as Ce/P). Interestingly, the strongest photoluminescence was observed in the CePO 4 nanowires synthesized with the initial Ce/P of 4:1, which proved to be the critical phase evolution point between the hexagonal and monoclinic CePO 4 . Therefore, the strong photoluminescence could be explained by the existence of the structure-sensitive energy level in the CePO 4 . This kind of photoluminescence enhancement would be a meaningful reference for design of other photoluminescent materials, in which the photoluminescent emission might be related to the structure-sensitive energy level. Additionally, the growth processes of CePO 4 nanowires based on related well-designed experiments were proposed.

Analysis of antibody aggregate content at extremely high concentrations using sedimentation velocity with a novel interference optics.

Science.gov (United States)

Schilling, Kristian; Krause, Frank

2015-01-01

Monoclonal antibodies represent the most important group of protein-based biopharmaceuticals. During formulation, manufacturing, or storage, antibodies may suffer post-translational modifications altering their physical and chemical properties. Such induced conformational changes may lead to the formation of aggregates, which can not only reduce their efficiency but also be immunogenic. Therefore, it is essential to monitor the amount of size variants to ensure consistency and quality of pharmaceutical antibodies. In many cases, antibodies are formulated at very high concentrations > 50 g/L, mostly along with high amounts of sugar-based excipients. As a consequence, all routine aggregation analysis methods, such as size-exclusion chromatography, cannot monitor the size distribution at those original conditions, but only after dilution and usually under completely different solvent conditions. In contrast, sedimentation velocity (SV) allows to analyze samples directly in the product formulation, both with limited sample-matrix interactions and minimal dilution. One prerequisite for the analysis of highly concentrated samples is the detection of steep concentration gradients with sufficient resolution: Commercially available ultracentrifuges are not able to resolve such steep interference profiles. With the development of our Advanced Interference Detection Array (AIDA), it has become possible to register interferograms of solutions as highly concentrated as 150 g/L. The other major difficulty encountered at high protein concentrations is the pronounced non-ideal sedimentation behavior resulting from repulsive intermolecular interactions, for which a comprehensive theoretical modelling has not yet been achieved. Here, we report the first SV analysis of highly concentrated antibodies up to 147 g/L employing the unique AIDA ultracentrifuge. By developing a consistent experimental design and data fit approach, we were able to provide a reliable estimation of the minimum

Use of anti-Aedes aegypti salivary extract antibody concentration to correlate risk of vector exposure and dengue transmission risk in Colombia.

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Berlin Londono-Renteria

Full Text Available Norte de Santander is a region in Colombia with a high incidence of dengue virus (DENV. In this study, we examined the serum concentration of anti-Aedes salivary gland extract (SGE antibodies as a biomarker of DENV infection and transmission, and assessed the duration of anti-SGE antibody concentration after exposure to the vector ceased. We also determined whether SGE antibody concentration could differentiate between positive and negative DENV infected individuals and whether there are differences in exposure for each DENV serotype. We observed a significant decrease in the concentration of IgG antibodies at least 40 days after returning to an "Ae. aegypti-free" area. In addition, we found significantly higher anti-SGE IgG concentrations in DENV positive patients with some difference in exposure to mosquito bites among DENV serotypes. We conclude that the concentration of IgG antibodies against SGE is an accurate indicator of risk of dengue virus transmission and disease presence.

A threshold concentration of anti-merozoite antibodies is required for protection from clinical episodes of malaria

DEFF Research Database (Denmark)

Murungi, Linda M; Kamuyu, Gathoni; Lowe, Brett

2013-01-01

Antibodies to selected Plasmodium falciparum merozoite antigens are often reported to be associated with protection from malaria in one epidemiological cohort, but not in another. Here, we sought to understand this paradox by exploring the hypothesis that a threshold concentration of antibodies i...

Reduction in serum sphingosine 1-phosphate concentration in malaria.

Directory of Open Access Journals (Sweden)

Chuchard Punsawad

Full Text Available Sphingosine 1-phosphate (S1P is a lipid mediator formed by the metabolism of sphingomyelin which is involved in the endothelial permeability and inflammation. Although the plasma S1P concentration is reportedly decreased in patients with cerebral malaria, the role of S1P in malaria is still unclear. The purpose of this study was to examine the impact of malaria on circulating S1P concentration and its relationship with clinical data in malaria patients. Serum S1P levels were measured in 29 patients with P. vivax, 30 patients with uncomplicated P. falciparum, and 13 patients with complicated P. falciparum malaria on admission and on day 7, compared with healthy subjects (n = 18 as control group. The lowest level of serum S1P concentration was found in the complicated P. falciparum malaria group, compared with P. vivax, uncomplicated P. falciparum patients and healthy controls (all p < 0.001. In addition, serum S1P level was positively correlated with platelet count, hemoglobin and hematocrit levels in malaria patients. In conclusions, low levels of S1P are associated with the severity of malaria, and are correlated with thrombocytopenia and anemia. These findings highlight a role of S1P in the severity of malaria and support the use of S1P and its analogue as a novel adjuvant therapy for malaria complications.

Transfer of Some Major and Trace Elements From Phosphate Rock to Super-Phosphate Fertilizers

International Nuclear Information System (INIS)

El-Reefya, H.I.; Bin-Jaz, A.A.; Zaied, M.E.; Badran, H.M.; Badran, H.M.

2014-01-01

This study assesses the transfer of some major and trace elements from phosphate rock (PR) to single (SSP) and triple (TSP) superphosphate fertilizers. Samples from a fertilizer plant and local market were collected and analyzed using inductively coupled plasma spectrometer. Cluster analysis indicated that the inner-relationship among the concentration of the elements in PR, SSP, and TSP are different. Only one element (Mo) has concentration in SSP higher than phosphate rock. The production process of these two types of superphosphate leads to transfer higher portion of Mn, B, Cu, Mo, Sr, and V present in the phosphate rock to SSP than TSP. The potentially hazardous element Cd is also transmitted more to SSP than TSP, and Cr is equally transferred to both types. The mean elemental concentrations normalized to the percentage of P 2 O 5 demonstrate that for most elements they are the higher concentrations in SSP are linked to the phosphate contents

Liver/kidney microsomal antibody type 1 and liver cytosol antibody type 1 concentrations in type 2 autoimmune hepatitis.

Science.gov (United States)

Muratori, L; Cataleta, M; Muratori, P; Lenzi, M; Bianchi, F B

1998-05-01

Liver/kidney microsomal antibody type 1 (LKM1) and liver cytosol antibody type 1 (LC1) are the serological markers of type 2 autoimmune hepatitis (AIH). Since LKM1 and LC1 react against two distinct liver specific autoantigens (cytochrome P450IID6 (CYP2D6) and a 58 kDa cytosolic polypeptide respectively), the aim was to see whether LKM1 and LC1 concentrations correlate with liver disease activity. Twenty one patients with type 2 AIH were studied. All sera were tested by indirect immunofluorescence, counterimmunoelectrophoresis, and immunoblotting visualised by enhanced chemiluminescence. To evaluate LKM1 and LC1 levels, the 50 kDa microsomal reactivity (corresponding to CYP2D6) and the 58 kDa cytosolic reactivity were quantified by densitometric analysis. Seven patients were positive for LKM1, nine for LC1, and five for both. Serial serum samples at onset and during immunosuppressive treatment were analysed in 13 patients (four positive for LKM1, six positive for LC1 and three positive for both). During remission, LKM1 concentration remained essentially unchanged in six of seven patients, and decreased in only one. Conversely, in two of nine patients, LC1 was completely lost, and, in the remaining seven, LC1 concentration was reduced by more than 50%. After immunosuppression tapering or withdrawal, flare ups of liver necrosis ensued with increasing LC1 concentration, but not LKM1. LC1 concentration, at variance with that of LKM1, parallels liver disease activity, and its participation in the pathogenic mechanisms of liver injury can be hypothesised.

High-throughput immunoturbidimetric assays for in-process determination of polyclonal antibody concentration and functionality in crude samples

DEFF Research Database (Denmark)

Bak, Hanne; Kyhse-Andersen, J.; Thomas, O.R.T.

2007-01-01

We present fast, simple immunoturbidimetric assays suitable for direct determination of antibody 'concentration' and 'functionality' in crude samples, such as in-process samples taken at various stages during antibody purification. Both assays display excellent linearity and analytical recovery. ...... antibodies, require only basic laboratory equipment, are robust, fast, cheap, easy to perform, and readily adapted to automation....

Quantitative trait loci analysis of phytate and phosphate concentrations in seeds and leaves of Brassica rapa

NARCIS (Netherlands)

Jianjun Zhao, Jianjun; Jamar, D.C.L.; Lou, P.; Wang, Y.; Wu, J.; Wang, X.; Bonnema, A.B.; Koornneef, M.; Vreugdenhil, D.

2008-01-01

Phytate, being the major storage form of phosphorus in plants, is considered to be an anti-nutritional substance for human, because of its ability to complex essential micronutrients. In the present study, we describe the genetic analysis of phytate and phosphate concentrations in Brassica rapa

Radiological impact of natural radioactivity in Egyptian phosphate rocks, phosphogypsum and phosphate fertilizers

International Nuclear Information System (INIS)

El-Bahi, S.M.; Sroor, A.; Mohamed, Gehan Y.; El-Gendy, N.S.

2017-01-01

In this study, the activity concentrations of the natural radionuclides in phosphate rocks and its products were measured using a high- purity germanium detector (HPGe). The obtained activity results show remarkable wide variation in the radioactive contents for the different phosphate samples. The average activity concentration of "2"3"5U, "2"3"8U, "2"2"6Ra, "2"3"2Th and "4"0K was found as (45, 1031, 786, 85 and 765 Bq/kg) for phosphate rocks, (28, 1234, 457, 123 and 819 Bq/kg) for phosphate fertilizers, (47, 663, 550, 79 and 870 Bq/kg) for phosphogypsum and (25, 543, 409, 54 and 897 Bq/kg) for single super phosphate respectively. Based on the measured activities, the radiological parameters (activity concentration index, absorbed gamma dose rate in outdoor and indoor and the corresponding annual effective dose rates and total excess lifetime cancer risk) were estimated to assess the radiological hazards. The total excess lifetime cancer risk (ELCR) has been calculated and found to be high in all samples, which related to high radioactivity, representing radiological risk for the health of the population. - Highlights: • Level of radioactivity of phosphate rocks and by-products samples. • The radiological health hazard parameters. • Radiological risk to the health of the population. • The excess lifetime cancer risk factor.

Buffer capacity of biologics--from buffer salts to buffering by antibodies.

Science.gov (United States)

Karow, Anne R; Bahrenburg, Sven; Garidel, Patrick

2013-01-01

Controlling pH is essential for a variety of biopharmaceutical process steps. The chemical stability of biologics such as monoclonal antibodies is pH-dependent and slightly acidic conditions are favorable for stability in a number of cases. Since control of pH is widely provided by added buffer salts, the current study summarizes the buffer characteristics of acetate, citrate, histidine, succinate, and phosphate buffers. Experimentally derived values largely coincide with values calculated from a model that had been proposed in 1922 by van Slyke. As high concentrated protein formulations become more and more prevalent for biologics, the self-buffering potential of proteins becomes of relevance. The current study provides information on buffer characteristics for pH ranges down to 4.0 and up to 8.0 and shows that a monoclonal antibody at 50 mg/mL exhibits similar buffer capacity as 6 mM citrate or 14 mM histidine (pH 5.0-6.0). Buffer capacity of antibody solutions scales linearly with protein concentration up to more than 200 mg/mL. At a protein concentration of 220 mg/mL, the buffer capacity resembles the buffer capacity of 30 mM citrate or 50 mM histidine (pH 5.0-6.0). The buffer capacity of monoclonal antibodies is practically identical at the process relevant temperatures 5, 25, and 40°C. Changes in ionic strength of ΔI=0.15, in contrast, can alter the buffer capacity up to 35%. In conclusion, due to efficient self-buffering by antibodies in the pH range of favored chemical stability, conventional buffer excipients could be dispensable for pH stabilization of high concentrated protein solutions. Copyright © 2013 American Institute of Chemical Engineers.

Maternally derived anti-fibroblast growth factor 23 antibody as new tool to reduce phosphorus requirement of chicks.

Science.gov (United States)

Ren, Zhouzheng; Bütz, Daniel E; Sand, Jordan M; Cook, Mark E

2017-04-01

Novel means to reduce phosphate input into poultry feeds and increase its retention would preserve world phosphate reserves and reduce environmental impact of poultry production. Here we show that a maternally derived antibody to a fibroblast growth factor-23 (FGF-23) peptide (GMNPPPYS) alleviated phosphorus deficiency in chicks fed low non-phytate phosphorus (nPP) diets. White Leghorn laying hens were vaccinated with either an adjuvant control or the synthetic FGF-23 peptide, and chicks with control or anti-FGF-23 maternal antibodies were fed a diet containing either 0.13 or 0.45% nPP (experiment 1), and 0.20 or 0.45% nPP (experiment 2) for 14 d. In both experiments, decreasing nPP from 0.45 to 0.13 or 0.20% decreased BW gain, G:F, excreta phosphorus, plasma phosphate, and plasma FGF-23 at all time periods examined (nPP main effect, P posture scores (d 7, 14) and bone lesion scores (d 14) decreased and plasma phosphate (d 14) increased in anti-FGF-23 chicks fed 0.13% nPP, compared to those with control antibody on the same diet (P < 0.05). In experiment 2, chicks with maternal anti-FGF-23 antibody had increased tibiotarsi ash (d 14), and plasma phosphate (d 14) and 1,25(OH)2D3 (d 14) levels, compared to chicks with control antibody (antibody main effect, P < 0.05). BW gain and G:F were increased in chicks with anti-FGF-23 antibody fed 0.20% nPP, compared to control antibody chicks on the same diet, at all time periods examined (P < 0.05). In conclusion, maternally-derived anti-FGF-23 antibody increased phosphorus retention in chicks fed diets containing either 0.13 or 0.20% nPP and thereby, reduced signs of phosphorus deficiency. © 2016 Poultry Science Association Inc.

Measurement of anti- acetylcholine receptor auto-antibodies in ...

African Journals Online (AJOL)

auto-antibodies in myasthenia gravis. K. J. Steenkamp, W. Duim, M. s. Myer,. S. C. K. Malfeld, R. Anderson. Two different acetylcholine receptor (AChR) preparations derived from ... the detection of AChR auto-antibodies in serum specimens from 20 ... 4°C. Thereafter, 1 ml of washing solution (phosphate- buffered saline ...

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......-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...

Concentration effect on the spectroscopic behavior of Tb3+ ions in zinc phosphate glasses

International Nuclear Information System (INIS)

Kesavulu, C.R.; Almeida Silva, Anielle Christine; Dousti, M.R.; Dantas, Noelio Oliveira; Camargo, A.S.S. de; Catunda, Tomaz

2015-01-01

Zinc phosphate glasses (PZABPTb) in the compositional system: P 2 O 5 –ZnO–Al 2 O 3 –BaO–PbO doped with variable Tb 3+ concentrations (1–5 wt% Tb 2 O 3 ) were prepared and characterized through absorption, excitation, emission and intensity decay rate measurements. The Judd–Ofelt model has been adopted to evaluate the radiative properties of the 5 D 4 → 7 F 6–3 emission transitions. The effect of Tb 3+ ion concentration on the emissions from the 5 D 3,4 excited levels is discussed in detail. Analysis of the intensity decay curves corresponding to blue and green emissions from levels 5 D 3 and 5 D 4 , respectively, allowed determination of effective lifetimes, which confirmed the Tb 3+ ion concentration quenching of the blue emission in these glasses. The decay curves for the 5 D 3 level are found to be non-exponential in nature for all the studied concentrations due to ion–ion energy transfer through cross-relaxation. In an attempt to identify the origin of the energy transfer mechanism, the decay curves were well fitted to the Inokuti–Hirayama model for S=6, which indicates that the energy transfer process is of dipole–dipole type. The optical band gap energy (E opt ) has been evaluated taking into account the ultraviolet edge of absorption spectra. - Highlights: • Tb 3+ -doped zinc phosphate glasses have been prepared by melt quenching technique. • Spectroscopic parameters were evaluated using the Judd–Ofelt theory. • Effects of Tb 3+ concentration on luminescence of the glasses were studied. • Strong intense laser transition for Tb 3+ ion in PZABPTb glasses is 5 D 4 → 7 F 5 (0.54 μm). • PZABPTb glasses could be used in the development of green color display devices and solid state visible lasers

Cerebrospinal Fluid Phosphate in Delirium after Hip Fracture

Directory of Open Access Journals (Sweden)

Ane-Victoria Idland

2017-09-01

Full Text Available Aims: Phosphate is essential for neuronal activity. We aimed to investigate whether delirium is associated with altered phosphate concentrations in cerebrospinal fluid (CSF and serum. Methods: Seventy-seven patients with hip fracture were assessed for delirium before and after acute surgery. Prefracture dementia was diagnosed by an expert panel. Phosphate was measured in CSF obtained immediately before spinal anesthesia (n = 77 and in serum (n = 47. CSF from 23 cognitively healthy elderly patients undergoing spinal anesthesia was also analyzed. Results: Hip fracture patients with prevalent delirium had higher CSF phosphate concentrations than those without delirium (median 0.63 vs. 0.55 mmol/L, p = 0.001. In analyses stratified on dementia status, this difference was only significant in patients with dementia. Serum phosphate was ∼1 mmol/L; there was no association between serum phosphate concentration and delirium status. CSF phosphate did not correlate with serum levels. Conclusion: Patients with delirium superimposed on dementia have elevated phosphate levels.

Uranium abundance in some sudanese phosphate ores

International Nuclear Information System (INIS)

Adam, A.A.; Eltayeb, M.A.H.

2009-01-01

This work was carried out mainly to analysis of some Sudanese phosphate ores, for their uranium abundance and total phosphorus content measured as P 2 O 5 %. For this purpose, 30 samples of two types of phosphate ore from Eastern Nuba Mountains, in Sudan namely, Kurun and Uro areas were examined. In addition, the relationship between uranium and major, and trace elements were obtained, also, the natural radioactivity of the phosphate samples was measured, in order to characterize and differentiate between the two types of phosphate ores. The uranium abundance in Uro phosphate with 20.3% P 2 O 5 is five time higher than in Kurun phosphate with 26.7% P 2 O 5 . The average of uranium content was found to be 56.6 and 310 mg/kg for Kurun and Uro phosphate ore, respectively. The main elements in Kurun and Uro phosphate ore are silicon, aluminum, and phosphorus, while the most abundant trace elements in these two ores are titanium, strontium and barium. Pearson correlation coefficient revealed that uranium in Kurun phosphate shows strong positive correlation with P 2 O 5 , and its distribution is essentially controlled by the variations of P2O5 concentration, whereas uranium in Uro phosphate shows strong positive correlation with strontium, and its distribution is controlled by the variations of Sr concentration. Uranium behaves in different ways in Kurun phosphate and in Uro phosphate. Uro phosphate shows higher concentrations of all the estimated radionuclides than Kurun phosphate. According to the obtained results, it can be concluded that Uro phosphate is consider as secondary uranium source, and is more suitable for uranium recovery, because it has high uranium abundance and low P 2 O 5 %, than Kurun phosphate. (authors) [es

Phosphorus release from phosphate rock and iron phosphate by low-molecular-weight organic acids.

Science.gov (United States)

Xu, Ren-kou; Zhu, Yong-guan; Chittleborough, David

2004-01-01

Low-molecular-weight(LMW) organic acids widely exist in soils, particularly in the rhizosphere. A series of batch experiments were carried out to investigate the phosphorus release from rock phosphate and iron phosphate by low-molecular-weight organic acids. Results showed that citric acid had the highest capacity to solubilize P from both rock and iron phosphate. P solubilization from rock phosphate and iron phosphate resulted in net proton consumption. P release from rock phosphate was positively correlated with the pKa values. P release from iron phosphate was positively correlated with Fe-organic acid stability constants except for aromatic acids, but was notcorrelated with pKa. Increase in the concentrations of organic acids enhanced P solubilization from both rock and iron phosphate almost linearly. Addition of phenolic compounds further increased the P release from iron phosphate. Initial solution pH had much more substantial effect on P release from rock phosphate than from iron phosphate.

Calcium phosphate nanoparticles as versatile carrier for small and large molecules across cell membranes

Energy Technology Data Exchange (ETDEWEB)

Sokolova, Viktoriya; Rotan, Olga; Klesing, Jan [University of Duisburg-Essen, Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany); Nalbant, Perihan [University of Duisburg-Essen, Faculty of Biology, Institute of Molecular Cell Biology (Germany); Buer, Jan; Knuschke, Torben; Westendorf, Astrid M. [University Hospital Essen, University of Duisburg-Essen, Institute of Medical Microbiology (Germany); Epple, Matthias, E-mail: matthias.epple@uni-due.de [University of Duisburg-Essen, Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany)

2012-06-15

The successful transport of molecules across the cell membrane is a key point in biology and medicine. In most cases, molecules alone cannot penetrate the cell membrane, therefore an efficient carrier is needed. Calcium phosphate nanoparticles (diameter: 100-250 nm, depending on the functionalization) were loaded with fluorescent oligonucleotides, peptide, proteins, antibodies, polymers or porphyrins and characterized by dynamic light scattering, nanoparticle tracking analysis and scanning electron microscopy. Any excess of molecules was removed by ultracentrifugation, and the dissolved molecules at the same concentration were used as control. The uptake of such fluorescence-labeled nanoparticles into HeLa cells was monitored by fluorescence microscopy and confocal laser scanning microscopy. Calcium phosphate nanoparticles were able to transport all molecules across the cell membrane, whereas the dissolved molecules alone were taken up only to a very small extent or even not at all.

Calcium phosphate nanoparticles as versatile carrier for small and large molecules across cell membranes

Science.gov (United States)

Sokolova, Viktoriya; Rotan, Olga; Klesing, Jan; Nalbant, Perihan; Buer, Jan; Knuschke, Torben; Westendorf, Astrid M.; Epple, Matthias

2012-06-01

The successful transport of molecules across the cell membrane is a key point in biology and medicine. In most cases, molecules alone cannot penetrate the cell membrane, therefore an efficient carrier is needed. Calcium phosphate nanoparticles (diameter: 100-250 nm, depending on the functionalization) were loaded with fluorescent oligonucleotides, peptide, proteins, antibodies, polymers or porphyrins and characterized by dynamic light scattering, nanoparticle tracking analysis and scanning electron microscopy. Any excess of molecules was removed by ultracentrifugation, and the dissolved molecules at the same concentration were used as control. The uptake of such fluorescence-labeled nanoparticles into HeLa cells was monitored by fluorescence microscopy and confocal laser scanning microscopy. Calcium phosphate nanoparticles were able to transport all molecules across the cell membrane, whereas the dissolved molecules alone were taken up only to a very small extent or even not at all.

Calcium phosphate nanoparticles as versatile carrier for small and large molecules across cell membranes

International Nuclear Information System (INIS)

Sokolova, Viktoriya; Rotan, Olga; Klesing, Jan; Nalbant, Perihan; Buer, Jan; Knuschke, Torben; Westendorf, Astrid M.; Epple, Matthias

2012-01-01

The successful transport of molecules across the cell membrane is a key point in biology and medicine. In most cases, molecules alone cannot penetrate the cell membrane, therefore an efficient carrier is needed. Calcium phosphate nanoparticles (diameter: 100–250 nm, depending on the functionalization) were loaded with fluorescent oligonucleotides, peptide, proteins, antibodies, polymers or porphyrins and characterized by dynamic light scattering, nanoparticle tracking analysis and scanning electron microscopy. Any excess of molecules was removed by ultracentrifugation, and the dissolved molecules at the same concentration were used as control. The uptake of such fluorescence-labeled nanoparticles into HeLa cells was monitored by fluorescence microscopy and confocal laser scanning microscopy. Calcium phosphate nanoparticles were able to transport all molecules across the cell membrane, whereas the dissolved molecules alone were taken up only to a very small extent or even not at all.

Concentration and distribution of elements in plants and soils near phosphate processing factories, Pocatello, Idaho

International Nuclear Information System (INIS)

Severson, R.C.; Gough, L.P.

1976-01-01

The processing of phosphatic shale near Pocatello, Idaho has a direct influence on the element content of local vegetation and soil. Samples of big sagebrush (Artemisia tridentata Nutt. subsp. tridentata) and cheatgrass (Bromus tectorum L.) show important negative relations between the concentration of certain elements (Cd, Cr, F, Ni, P, Se, U, V, and Zn) and distance from phosphate processing factories. Plant tissues within 3 km of the processing factories contain unusually high amounts of these elements except Ni and Se. Important negative relations with distance were also found for certain elements (Be, F, Fe, K, Li, Pb, Rb, Th, and Zn) in A-horizon soil. Amounts of seven elements (Be, F, Li, Pb, Rb, Th, and Zn) being contributed to the upper 5 cm of the soil by phosphate processing, as well as two additional elements (U and V) suspected as being contributed to soil, were estimated, with F showing the greatest increase (about 300 kg/ha) added to soils as far as 4 km downwind from the factories. The greatest number of important relations for both plants and soils was found downwind (northeast) of the processing factories

A cross-sectional study of tetanus and diphtheria antibody concentrations post vaccination among lung transplant patients compared with healthy individuals.

Science.gov (United States)

Rohde, K A; Cunningham, K C; Henriquez, K M; Nielsen, A R; Worzella, S L; Hayney, M S

2014-12-01

Lung transplant (LuTx) patients are routinely immunized against tetanus and diphtheria. However, few studies have been done to measure serologic immunity in the transplant population. The primary objective of this study was to compare tetanus and diphtheria antibody concentrations in LuTx vs. healthy subjects. Serum was used from an available sample of 111 total individuals (n = 36 healthy; n = 75 LuTx). Tetanus and diphtheria antibody concentrations were measured using an enzyme-linked immunosorbant assay method. A statistically significant difference in both tetanus and diphtheria antibody concentrations was found between the groups. The median concentration of tetanus antibody was higher for healthy individuals compared with the LuTx group (3.2 IU/mL [1.2-5.2 interquartile range {IQR}] vs. 1.3 IU/mL [0.4-2.6 IQR], respectively; P = 0.0001). No difference in time was found since the last tetanus-diphtheria vaccine or tetanus-diphtheria-pertussis vaccine dose between the groups (healthy 76.5 months [16-114 IQR] vs. LuTx 74.5 months [45-118 IQR]; P = 0.44). Tetanus and diphtheria immunizations are recommended for LuTx patients to reduce the risk of infection. Because the LuTx group has lower antibody concentrations, further studies should investigate the possible need for more frequent tetanus and diphtheria boosters. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Phosphate buffer and salt medium concentrations affect the inactivation of T4 phage by platinum(II) complexes

DEFF Research Database (Denmark)

Pedersen, Henrik B.; Josephsen, Jens; Kerszman, Gustaw

1985-01-01

-Tris) buffer and HEPES buffer. The phosphate abolishes the antiphage activity of the platinum complexes probably by some sort of complex formation. This together with dimerization reactions qualitatively explains the tailing off of the phage inactivation rate. High concentrations of NaNO3 as the salt medium...

Stratification of antibody-positive subjects by antibody level reveals an impact of immunogenicity on pharmacokinetics.

Science.gov (United States)

Zhou, Lei; Hoofring, Sarah A; Wu, Yu; Vu, Thuy; Ma, Peiming; Swanson, Steven J; Chirmule, Narendra; Starcevic, Marta

2013-01-01

The availability of highly sensitive immunoassays enables the detection of antidrug antibody (ADA) responses of various concentrations and affinities. The analysis of the impact of antibody status on drug pharmacokinetics (PK) is confounded by the presence of low-affinity or low-concentration antibody responses within the dataset. In a phase 2 clinical trial, a large proportion of subjects (45%) developed ADA following weekly dosing with AMG 317, a fully human monoclonal antibody therapeutic. The antibody responses displayed a wide range of relative concentrations (30 ng/mL to >13 μg/mL) and peaked at various times during the study. To evaluate the impact of immunogenicity on PK, AMG 317 concentration data were analyzed following stratification by dose group, time point, antibody status (positive or negative), and antibody level (relative concentration). With dose group as a stratifying variable, a moderate reduction in AMG 317 levels (AMG 317 levels was revealed when antibody data was stratified by both time point and antibody level. In general, high ADA concentrations (>500 ng/mL) and later time points (week 12) were associated with significantly (up to 97%) lower trough AMG 317 concentrations. The use of quasi-quantitative antibody data and appropriate statistical methods was critical for the most comprehensive evaluation of the impact of immunogenicity on PK.

Higher Plasma Concentration of Food-Specific Antibodies in Persons with Autistic Disorder in Comparison to Their Siblings

Science.gov (United States)

Trajkovski, Vladimir; Petlichkovski, Aleksandar; Efinska-Mladenovska, Olivija; Trajkov, Dejan; Arsov, Todor; Strezova, Ana; Ajdinski, Ljubomir; Spiroski, Mirko

2008-01-01

Specific IgA, IgG, and IgE antibodies to food antigens in 35 participants with autistic disorder and 21 of their siblings in the Republic of Macedonia were examined. Statistically significant higher plasma concentration of IgA antibodies against alpha-lactalbumin, beta-lactoglobulin, casein, and gliadin were found in the children with autistic…

Sandwich enzyme-linked immunosorbent assay (ELISA) for measuring the concentration of, and detection of antibodies to, Aujeszky's disease virus.

Science.gov (United States)

Kardi, V; Szegletes, E; Perényi, T; Pergel, I; Smal, Z

1990-01-01

A double antibody sandwich enzyme-linked immunosorbent assay (ELISA) was developed for measuring Aujeszky's disease virus (ADV) antigen concentration and an inhibition technique based on the former was developed for detection of antibodies to ADV. The results were checked by determining the cytopathic and serum neutralization titres. The correlation was satisfactory in both cases, with correlation coefficients above 0.8. When measuring ADV antigen concentration, the lower limit of detection was 10(3) TCID 50/0.2 ml. The sensitivity of ELISA in detecting antibodies to ADV was found to be superior to that of the serum neutralization test and, thus, enabled the testing of rabbit and guinea-pig sera.

The Effect of Moderate Dietary Protein and Phosphate Restriction on Calcium-Phosphate Homeostasis in Healthy Older Cats.

Science.gov (United States)

Geddes, R F; Biourge, V; Chang, Y; Syme, H M; Elliott, J

2016-09-01

Dietary phosphate and protein restriction decreases plasma PTH and FGF-23 concentrations and improves survival time in azotemic cats, but has not been examined in cats that are not azotemic. Feeding a moderately protein- and phosphate-restricted diet decreases PTH and FGF-23 in healthy older cats and thereby slows progression to azotemic CKD. A total of 54 healthy, client-owned cats (≥ 9 years). Prospective double-blinded randomized placebo-controlled trial. Cats were assigned to test diet (protein 76 g/Mcal and phosphate 1.6 g/Mcal) or control diet (protein 86 g/Mcal and phosphate 2.6 g/Mcal) and monitored for 18 months. Changes in variables over time and effect of diet were assessed by linear mixed models. A total of 26 cats ate test diet and 28 cats ate control diet. There was a significant effect of diet on urinary fractional excretion of phosphate (P = 0.045), plasma PTH (P = 0.005), and ionized calcium concentrations (P = 0.018), but not plasma phosphate, FGF-23, or creatinine concentrations. Plasma PTH concentrations did not significantly change in cats fed the test diet (P = 0.62) but increased over time in cats fed the control diet (P = 0.001). There was no significant treatment effect of the test diet on development of azotemic CKD (3 of 26 (12%) test versus 3 of 28 (11%) control, odds ratio 1.09 (95% CI 0.13-8.94), P = 0.92). Feeding a moderately protein- and phosphate-restricted diet has effects on calcium-phosphate homeostasis in healthy older cats and is well tolerated. This might have an impact on renal function and could be useful in early chronic kidney disease. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Aluminum phosphate shows more adjuvanticity than Aluminum hydroxide in recombinant hepatitis –B vaccine formulation

Directory of Open Access Journals (Sweden)

2008-08-01

Full Text Available Background: Although a number of investigation have been carried out to find alternative adjuvants to aluminum salts in vaccine formulations, they are still extensively used due to their good track record of safety, low cost and proper adjuvanticity with a variety of antigens. Adsorption of antigens onto aluminum compounds depends heavily on electrostatic forces between adjuvant and antigen. Commercial recombinant protein hepatitis B vaccines containing aluminum hydroxide as adjuvant is facing low induction of immunity in some sections of the vaccinated population. To follow the current global efforts in finding more potent hepatitis B vaccine formulation, adjuvanticity of aluminum phosphate has been compared to aluminum hydroxide. Materials and methods: The adjuvant properties of aluminum hydroxide and aluminum phosphate in a vaccine formulation containing a locally manufactured hepatitis B (HBs surface antigen was evaluated in Balb/C mice. The formulations were administered intra peritoneally (i.p. and the titers of antibody which was induced after 28 days were determined using ELISA technique. The geometric mean of antibody titer (GMT, seroconversion and seroprotection rates, ED50 and relative potency of different formulations were determined. Results: All the adjuvanicity markers obtained in aluminum phosphate formulation were significantly higher than aluminum hydroxide. The geometric mean of antibody titer of aluminum phosphate was approximately three folds more than aluminum hydroxide. Conclusion: Aluminum phosphate showed more adjuvanticity than aluminum hydroxide in hepatitis B vaccine. Therefore the use of aluminum phosphate as adjuvant in this vaccine may lead to higher immunity with longer duration of effects in vaccinated groups.

Geographic variation in the relationships of temperature, salinity or sigma sub t versus plant nutrient concentrations in the world ocean. [silicic acid, nitrate, and phosphate concentration

Science.gov (United States)

Kamykowski, D.; Zentara, S. J.

1985-01-01

A NODC data set representing all regions of the world ocean was analyzed for temperature and sigma-t relationships with nitrate, phosphate or silicic acid. Six cubic regressions were for each ten degree square of latitude and longitude containing adequate data. World maps display the locations that allow the prediction of plant nutrient concentrations from temperature or sigma-t. Geographic coverage improves along the sequence: nitrate, phosphate, and silicic acid and is better for sigma-t than for temperature. Contour maps of the approximate temperature of sigma-t at which these nitrients are no longer measurable in a parcel of water are generated, based on a percentile analysis of the temperature or sigma-t at which less than a selected amount of plant nutrient occurs. Results are stored on magnetic tape in tabular form. The global potential to predict plant nutrient concentrations from remotely sensed temperature of sigma-t and to emphasize the latitudinally and longitudinally changing phytoplankton growth environment in present and past oceans is demonstrated.

Phosphate additives in food--a health risk.

Science.gov (United States)

Ritz, Eberhard; Hahn, Kai; Ketteler, Markus; Kuhlmann, Martin K; Mann, Johannes

2012-01-01

Hyperphosphatemia has been identified in the past decade as a strong predictor of mortality in advanced chronic kidney disease (CKD). For example, a study of patients in stage CKD 5 (with an annual mortality of about 20%) revealed that 12% of all deaths in this group were attributable to an elevated serum phosphate concentration. Recently, a high-normal serum phosphate concentration has also been found to be an independent predictor of cardiovascular events and mortality in the general population. Therefore, phosphate additives in food are a matter of concern, and their potential impact on health may well have been underappreciated. We reviewed pertinent literature retrieved by a selective search of the PubMed and EU databases (www.zusatzstoffe-online.de, www.codexalimentarius.de), with the search terms "phosphate additives" and "hyperphosphatemia." There is no need to lower the content of natural phosphate, i.e. organic esters, in food, because this type of phosphate is incompletely absorbed; restricting its intake might even lead to protein malnutrition. On the other hand, inorganic phosphate in food additives is effectively absorbed and can measurably elevate the serum phosphate concentration in patients with advanced CKD. Foods with added phosphate tend to be eaten by persons at the lower end of the socioeconomic scale, who consume more processed and "fast" food. The main pathophysiological effect of phosphate is vascular damage, e.g. endothelial dysfunction and vascular calcification. Aside from the quality of phosphate in the diet (which also requires attention), the quantity of phosphate consumed by patients with advanced renal failure should not exceed 1000 mg per day, according to the guidelines. Prospective controlled trials are currently unavailable. In view of the high prevalence of CKD and the potential harm caused by phosphate additives to food, the public should be informed that added phosphate is damaging to health. Furthermore, calls for labeling

Magnetic Particle-Based Immunoassay of Phosphorylated p53 Using Protein-Cage Templated Lead Phosphate and Carbon Nanospheres for Signal Amplification

Energy Technology Data Exchange (ETDEWEB)

Chen, Aiqiong; Bao, Yuanwu; Ge, Xiaoxiao; Shin, Yongsoon; Du, Dan; Lin, Yuehe

2012-11-20

Phosphorylated p53 at serin 15 (phospho-p53-15) is a potential biomarker of Gamma-radiation exposure. In this paper, we described a new magnetic particles (MPs)-based electrochemical immunoassay of human phospho-p53-15 using carbon nanospheres (CNS) and protein-cage templated lead phosphate nanoparticles for signal amplification. Greatly enhanced sensitivity was achieved by three aspects: 1) The protein-cage nanoparticle (PCN) and p53-15 signal antibody (p53-15 Ab2) are linked to CNS (PCNof each apoferritin; 3) MPs capture a large amount of primary antibodies. Using apoferritin templated metallic phosphate instead of enzyme as label has the advantage of eliminating the addition of mediator or immunoreagents and thus makes the immunoassay system simpler. The subsequent stripping voltammetric analysis of the released lead ions were detected on a disposable screen printed electrode. The response current was proportional to the phospho-p53-15 concentration in the range of 0.02 to 20 ng mL-1 with detection limit of 0.01 ng mL-1. This method shows a good stability, reproducibility and recovery.

Specific proliferation rates of human osteoblasts on calcium phosphate surfaces with variable concentrations of α-TCP

International Nuclear Information System (INIS)

Santos, Euler A. dos; Farina, Marcos; Soares, Gloria A.

2007-01-01

Ideally, ceramics used in the repair of bone defects need to be resorbed and replaced by newly formed bone in vivo. Tricalcium phosphate (TCP) has been widely used in association with hydroxyapatite (HA) due to its higher resorption kinetics when compared with HA alone. The aim of our study was to quantitatively investigate the effect of α-tricalcium phosphate (α-TCP) on human osteoblasts' adhesion and proliferation. Ceramic samples with variable concentrations of α-TCP and HA were produced by the calcination of calcium-deficient and stoichiometric HA. Human osteoblasts were cultured on the materials in three distinct experiments with different concentrations of cells. Numerical evaluation of cellular growth along time in culture was performed for each condition. The quantity of cells seeded onto the ceramics seems to influence the osteoblast behavior once proliferation was lower when more cells were seeded onto the samples. However, a smaller content of α-TCP in relation to that of HA did not significantly modify the specific proliferation rates of the osteoblasts. Only after a long time in culture, the increasing of the α-TCP content seems to change the cells' behavior

Determination of Aluminum in Dialysis Concentrates by Atomic Absorption Spectrometry after Coprecipitation with Lanthanum Phosphate.

Science.gov (United States)

Selvi, Emine Kılıçkaya; Şahin, Uğur; Şahan, Serkan

2017-01-01

This method was developed for the determination of trace amounts of aluminum(III) in dialysis concentrates using atomic absorption spectrometry after coprecipitation with lanthanum phosphate. The analytical parameters that influenced the quantitative coprecipitation of analyte including amount of lanthanum, amount of phosfate, pH and duration time were optimized. The % recoveries of the analyte ion were in the range of 95-105 % with limit of detection (3s) of 0.5 µg l -1 . Preconcentration factor was found as 1000 and Relative Standard Deviation (RSD) % value obtained from model solutions was 2.5% for 0.02 mg L -1 . The accuracy of the method was evaluated with standard reference material (CWW-TMD Waste Water). The method was also applied to most concentrated acidic and basic dialysis concentrates with satisfactory results.

Isolation and identification of a phosphate solubilising fungus from soil of a phosphate mine in Chaluse, Iran

Directory of Open Access Journals (Sweden)

Raheleh Jamshidi

2016-07-01

Full Text Available Microbial solubilisation of phosphorus from insoluble phosphates is an environmental friendly and cost effective approach in sustainable soil management. Introducing the indigenous microorganisms to soil requires shorter adaptation period and causes fewer ecological distortions than exogenous microorganisms. This study was conducted to isolate and identify the indigenous fungi for phosphate solubilisation in Mazandaran, Iran. A potent phosphate solubilising fungus was isolated from an Iranian phosphate mine and selected for solubilisation of rock phosphate (RP. The identified fungus was characterised by calmodulin-based polymerase chain reaction method as Aspergillus tubingensis SANRU (Sari Agricultural Sciences and Natural Resources University. The phosphate solubilisation ability of the fungal strain was carried out in shake-flask leaching experiments containing various concentrations of RP (1%, 2%, 4%, or 8% w/v. The maximum P solubilisation rate of 347 mg/l was achieved at 1% of RP concentration on day 9. The regression analysis indicated that the P solubilised mainly through acidification. This study shows the possibility of using A. tubingensis SANRU for application in the management of P fertilisation.

Investigation of spectral interference effects on determination of uranium concentration in phosphate ore by inductively coupled plasma optical emission spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Bachari, Ayoob H.; Jalali, Fatemeh; Alahyarizadeh, Ghasem [Tehran Univ. (Iran, Islamic Republic of). Engineering Dept.

2017-04-01

Effects of spectral interferences on determination of the uranium concentration in phosphate ore were investigated by inductively coupled plasma optical emission spectroscopy (ICP-OES). Eleven high intensity emission lines including four lines recommended by ICP-OES apparatus were chosen to determine the uranium concentration. The ore samples were collected from phosphate acid producing industry in the south of Iran. Three different acid combinations [(HNO{sub 3}:HCl:HF-2:6:2), (H{sub 3}PO{sub 4}:H{sub 2}SO{sub 4}:HF-3:3:3), (HNO{sub 3}:H{sub 2}O{sub 2}:HF-4:2:2)] used in microwave digestion method to explore the spectral interference effects in different solvent environments. The results showed that the trusty uranium concentration, obtained in the 367.007 nm, 386.592 nm, 389.036 nm and 409.014 nm by second acid digestion method which were 0.665 ppm, 0.972 ppm, 0.670 ppm and 0.801 ppm, respectively. Although the line of 409.014 nm was reported as the best line for determining of the uranium concentration in several literatures, the results showed that this line has a significant spectral interference with vanadium in some ores which should be considered in determining of the uranium concentration. Spectral interference effects of some elements which have high concentrations in the phosphate ore including Ca, Fe, Mg, Pb, V, Mn, and Ti on the line intensities were also investigated. Results indicated that the chosen elements affect emission intensities of all of 11 lines. They also indicated that the line of 409.014 nm provides a trusty precision in the determination of the uranium concentration in the ore sample with low vanadium concentration (at least, U/V ratio of 1:5). Results show that the line of 409.014 nm provides acceptable precision with some corrections in comparison with other selected lines. For instance in high concentrations of other elements including Fe and Ti in the ore samples, strong influences on the line intensities of the 367.007 nm (by Fe

Increasing synthetic serum substitute (SSS) concentrations in P1 glucose/phosphate-free medium improves implantation rate: a comparative study.

Science.gov (United States)

Ben-Yosef, D; Yovel, I; Schwartz, T; Azem, F; Lessing, J B; Amit, A

2001-11-01

To assess the comparative efficacy of IVF medium (MediCult, with 5.2 mM glucose) and a glucose/phosphate-free medium, P1 (Irvine Scientific), and to investigate the influence of increasing the serum supplementation (synthetic serum substitute; SSS; Irvine Scientific) to P1 on embryo development and implantation. Patients were randomly assigned to IVF medium (Group 1, cycles n = 172) or P1 supplemented with 10% SSS (Group 2, cycles n = 229) according to the medium scheduled for use on the day of oocyte retrieval. Another 555 IVF consequent cycles (Group 3) were performed using increased SSS concentrations (20%) in P1 medium. In this large series of IVF cycles, we herein demonstrate that significantly higher pregnancy and implantation rates were found when embryos were cultured in glucose/phosphate-free medium P1 supplemented with 20% SSS compared to supplementation with the lower SSS concentration and with IVF medium.

Concentration effect on the spectroscopic behavior of Tb{sup 3+} ions in zinc phosphate glasses

Energy Technology Data Exchange (ETDEWEB)

Kesavulu, C.R., E-mail: crkesavulu2005@gmail.com [Instituto de Fisica de São Carlos, Universidade de São Paulo, Avenida Trabalhador Sãocarlense 400, São Carlos, SP (Brazil); Almeida Silva, Anielle Christine [Laboratorio de Novos Materials Isolantes e Semicondutores (LNMIS), Instituto de Física, Universidade Federal de Uberândia, MG (Brazil); Dousti, M.R. [Instituto de Fisica de São Carlos, Universidade de São Paulo, Avenida Trabalhador Sãocarlense 400, São Carlos, SP (Brazil); Dantas, Noelio Oliveira [Laboratorio de Novos Materials Isolantes e Semicondutores (LNMIS), Instituto de Física, Universidade Federal de Uberândia, MG (Brazil); Camargo, A.S.S. de; Catunda, Tomaz [Instituto de Fisica de São Carlos, Universidade de São Paulo, Avenida Trabalhador Sãocarlense 400, São Carlos, SP (Brazil)

2015-09-15

Zinc phosphate glasses (PZABPTb) in the compositional system: P{sub 2}O{sub 5}–ZnO–Al{sub 2}O{sub 3}–BaO–PbO doped with variable Tb{sup 3+} concentrations (1–5 wt% Tb{sub 2}O{sub 3}) were prepared and characterized through absorption, excitation, emission and intensity decay rate measurements. The Judd–Ofelt model has been adopted to evaluate the radiative properties of the {sup 5}D{sub 4}→{sup 7}F{sub 6–3} emission transitions. The effect of Tb{sup 3+} ion concentration on the emissions from the {sup 5}D{sub 3,4} excited levels is discussed in detail. Analysis of the intensity decay curves corresponding to blue and green emissions from levels {sup 5}D{sub 3} and {sup 5}D{sub 4}, respectively, allowed determination of effective lifetimes, which confirmed the Tb{sup 3+} ion concentration quenching of the blue emission in these glasses. The decay curves for the {sup 5}D{sub 3} level are found to be non-exponential in nature for all the studied concentrations due to ion–ion energy transfer through cross-relaxation. In an attempt to identify the origin of the energy transfer mechanism, the decay curves were well fitted to the Inokuti–Hirayama model for S=6, which indicates that the energy transfer process is of dipole–dipole type. The optical band gap energy (E{sub opt}) has been evaluated taking into account the ultraviolet edge of absorption spectra. - Highlights: • Tb{sup 3+}-doped zinc phosphate glasses have been prepared by melt quenching technique. • Spectroscopic parameters were evaluated using the Judd–Ofelt theory. • Effects of Tb{sup 3+} concentration on luminescence of the glasses were studied. • Strong intense laser transition for Tb{sup 3+} ion in PZABPTb glasses is {sup 5}D{sub 4}→{sup 7}F{sub 5} (0.54 μm). • PZABPTb glasses could be used in the development of green color display devices and solid state visible lasers.

Nanoparticle-based immunosensor with apoferritin templated metallic phosphate label for quantification of phosphorylated acetylcholinesterase

Energy Technology Data Exchange (ETDEWEB)

Du, Dan; Chen, Aiqiong; Xie, Yunying; Zhang, Aidong; Lin, Yuehe

2011-05-15

A new sandwich-like electrochemical immunosensor has been developed for quantification of organophosphorylated acetylcholinesterase (OP-AChE), an exposure biomarker of organophosphate pesticides and nerve agents. Zirconia nanoparticles (ZrO2 NPs) were anchored on a screen printed electrode (SPE) to preferably capture OP-AChE adducts by metal chelation with phospho-moieties, which was selectively recognized by lead phosphate-apoferritin labeled anti-AChE antibody (LPA-anti-AChE). The sandwich-like immunoreactions were performed among ZrO2 NPs, OP-AChE and LPA-anti-AChE to form ZrO2/OP-AChE/LPA-anti-AChE complex and the released lead ions were detected on a disposable SPE. The binding affinity was investigated by both square wave voltammetry (SWV) and quartz crystal microbalance (QCM) measurements. The proposed immunosensor yielded a linear response current over a broad OP-AChE concentrations range from 0.05 nM to 10 nM, with detection limit of 0.02 nM, which has enough sensitivity for monitoring of low-dose exposure to OPs. This method avoids the drawback of unavailability of commercial OP-specific antibody as well as amplifies detection signal by using apoferritin encoded metallic phosphate nanoparticle tags. This nanoparticle-based immunosensor offers a new method for rapid, sensitive, selective and inexpensive quantification of phosphorylated adducts for monitoring of OP pesticides and nerve agents exposures.

Nanoparticle-based immunosensor with apoferritin templated metallic phosphate label for quantification of phosphorylated acetylcholinesterase

International Nuclear Information System (INIS)

Du, Dan; Chen, Aiqiong; Xie, Yunying; Zhang, Aidong; Lin, Yuehe

2011-01-01

A new sandwich-like electrochemical immunosensor has been developed for quantification of organophosphorylated acetylcholinesterase (OP-AChE), an exposure biomarker of organophosphate pesticides and nerve agents. Zirconia nanoparticles (ZrO2 NPs) were anchored on a screen printed electrode (SPE) to preferably capture OP-AChE adducts by metal chelation with phospho-moieties, which was selectively recognized by lead phosphate-apoferritin labeled anti-AChE antibody (LPA-anti-AChE). The sandwich-like immunoreactions were performed among ZrO2 NPs, OP-AChE and LPA-anti-AChE to form ZrO2/OP-AChE/LPA-anti-AChE complex and the released lead ions were detected on a disposable SPE. The binding affinity was investigated by both square wave voltammetry (SWV) and quartz crystal microbalance (QCM) measurements. The proposed immunosensor yielded a linear response current over a broad OP-AChE concentrations range from 0.05 nM to 10 nM, with detection limit of 0.02 nM, which has enough sensitivity for monitoring of low-dose exposure to OPs. This method avoids the drawback of unavailability of commercial OP-specific antibody as well as amplifies detection signal by using apoferritin encoded metallic phosphate nanoparticle tags. This nanoparticle-based immunosensor offers a new method for rapid, sensitive, selective and inexpensive quantification of phosphorylated adducts for monitoring of OP pesticides and nerve agents exposures.

31P-Nuclear Magnetic Resonance Determination of Phosphate Compartmentation in Leaves of Reproductive Soybeans (Glycine max L.) as Affected by Phosphate Nutrition 1

Science.gov (United States)

Lauer, Michael J.; Blevins, Dale G.; Sierzputowska-Gracz, Hanna

1989-01-01

Most leaf phosphorus is remobilized to the seed during reproductive development in soybean. We determined, using 31P-NMR, the effect phosphorus remobilization has on vacuolar inorganic phosphate pool size in soybean (Glycine max [L.] Merr.) leaves with respect to phosphorus nutrition and plant development. Phosphate compartmentation between cytoplasmic and vacuolar pools was observed and followed in intact tissue grown hydroponically, at the R2, R4, and R6 growth stages. As phosphorus in the nutrient solution decreased from 0.45 to 0.05 millimolar, the vacuolar phosphate peak became less prominent relative to cytoplasmic phosphate and hexose monophosphate peaks. At a nutrient phosphate concentration of 0.05 millimolar, the vacuolar phosphate peak was not detectable. At higher levels of nutrient phosphate, as plants progressed from the R2 to the R6 growth stage, the vacuolar phosphate peak was the first to disappear, suggesting that storage phosphate was remobilized to a greater extent than metabolic phosphate. Under suboptimal phosphate nutrition (≤ 0.20 millimolar), the hexose monophosphate and cytoplasmic phosphate peaks declined earlier in reproductive development than when phosphate was present in optimal amounts. Under low phosphate concentrations (0.05 millimolar) cytoplasmic phosphate was greatly reduced. Carbon metabolism was coincidently disrupted under low phosphate nutrition as shown by the appearance of large, prominent starch grains in the leaves. Cytoplasmic phosphate, and leaf carbon metabolism dependent on it, are buffered by vacuolar phosphate until late stages of reproductive growth. Images Figure 4 PMID:16666705

Optimization of a model of red blood cells for the study of anti-oxidant drugs, in terms of concentration of oxidant and phosphate buffer.

Science.gov (United States)

Bureau, A; Lahet, J-J; Lenfant, F; Bouyer, F; Petitjean, M; Chaillot, B; Freysz, M

2005-08-01

The aggression of erythrocytes by an oxidative stress induces hemolysis. This paper aims to valid a model of erythrocytes in terms of composition of the phosphate buffer solution and of concentration of a well-known oxidant, AAPH. Three compositions of phosphate buffer solution are mixed with three concentrations of oxidant. The influence of these two parameters on hemolysis is independently studied by a variance analysis and a Kruskal-Wallis test when ANOVA is not available. The hemolysis rate increases with time at fixed oxidant concentration, but is not influenced by the composition of the buffer solution. The highest hemolysis rate, 90%, was only measured within 2 h with the highest oxidant concentration. If we retain this concentration of oxidant, the lower concentration of the buffer can by eliminated by a significant less hemolysis and the highest concentration of the buffer can by chosen in regard of the better precision for a similar hemolysis compared to the mean buffer. We hope to study the effect of anti-oxidant agent with such a model of erythrocytes.

Aqueous phosphate removal using nanoscale zero-valent iron

International Nuclear Information System (INIS)

Almeelbi, Talal; Bezbaruah, Achintya

2012-01-01

Nanoscale zero-valent iron (NZVI) particles have been used for the remediation of a wide variety of contaminants. NZVI particles have high reactivity because of high reactive surface area. In this study, NZVI slurry was successfully used for phosphate removal and recovery. Batch studies conducted using different concentrations of phosphate (1, 5, and 10 mg PO 4 3− -P/L with 400 mg NZVI/L) removed ∼96 to 100 % phosphate in 30 min. Efficacy of the NZVI in phosphate removal was found to 13.9 times higher than micro-ZVI (MZVI) particles with same NZVI and MZVI surface area concentrations used in batch reactors. Ionic strength, sulfate, nitrate, and humic substances present in the water affected in phosphate removal by NZVI but they may not have any practical significance in phosphate removal in the field. Phosphate recovery batch study indicated that better recovery is achieved at higher pH and it decreased with lowering of the pH of the aqueous solution. Maximum phosphate recovery of ∼78 % was achieved in 30 min at pH 12. The successful rapid removal of phosphate by NZVI from aqueous solution is expected to have great ramification for cleaning up nutrient rich waters.

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 pregnancy (r = -0.590, p pregnancy BMI was significantly correlated with AF uric acid concentration (r = 0.460, p sodium (r = 0.254, p = 0.070) levels. Multiple linear regression indicated that mid-trimester AF uric acid and phosphate levels were significantly related to birth weight centiles (R(2)( )= 0.345, p pregnancy BMI is significantly correlated with AF 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.

Investigating high-concentration monoclonal antibody powder suspension in nonaqueous suspension vehicles for subcutaneous injection.

Science.gov (United States)

Bowen, Mayumi; Armstrong, Nick; Maa, Yuh-Fun

2012-12-01

Developing high-concentration monoclonal antibody (mAb) liquid formulations for subcutaneous (s.c.) administration is challenging because increased viscosity makes injection difficult. To overcome this obstacle, we investigated a nonaqueous powder suspension approach. Three IgG1 mAbs were spray dried and suspended at different concentrations in Miglyol® 840, benzyl benzoate, or ethyl lactate. Suspensions were characterized for viscosity, particle size, and syringeability; physical stability was visually inspected. Suspensions generally outperformed liquid solutions for injectability despite higher viscosity at the same mAb concentrations. Powder formulations and properties had little effect on viscosity or injectability. Ethyl lactate suspensions had lowest viscosity (Miglyol® 840 improved overall performance in high mAb concentration suspensions. This study demonstrated the viability of high mAb concentration (>300 mg/mL) in suspension formulations for s.c. administration. Copyright © 2012 Wiley Periodicals, Inc.

Biodegradation of tert-butylphenyl diphenyl phosphate

International Nuclear Information System (INIS)

Heitkamp, M.A.; Freeman, J.P.; Cerniglia, C.E.

1986-01-01

The biodegradation of tert-butylphenyl diphenyl phosphate (BPDP) was examined in microcosms containing sediment and water from five different ecosystems as part of studies to elucidate the environmental fate of phosphate ester flame retardants. Biodegradation of [ 14 C]BPDP was monitored in the environmental microcosms by measuring the evolution of 14 CO 2 . Over 37% of BPDP was mineralized after 8 weeks in microcosms from an ecosystem which had chronic exposure to agricultural chemicals. In contrast, only 1.7% of BPDP was degraded to 14 CO 2 in samples collected from a noncontaminated site. The exposure concentration of BPDP affected the percentage which was degraded to 14 CO 2 in microcosms from the two most active ecosystems. Mineralization was highest at a concentration of 0.1 mg of BPDP and was inhibited with 10- and 100-fold higher concentrations of BPDP. The authors observed adaptive increases in both microbial populations and phosphoesterase enzymes in some sediments acclimated to BPDP. Chemical analyses of the residues in the microcosms indicated undegraded BPDP and minor amounts of phenol, tert-butylphenol, diphenyl phosphate, and triphenyl phosphate as biodegradation products. These data suggest that the microbial degradation of BPDP results from at least three catabolic processes and is highest when low concentrations of BPDP are exposed to sediment microorganisms of eutrophic ecosystems which have high phosphotri- and diesterase activities and previous exposure to anthropogenic chemicals

Are Polyphosphates or Phosphate Esters Prebiotic Reagents?

Science.gov (United States)

Keefe, Anthony D.; Miller, Stanley L.

1995-01-01

It is widely held that there was a phosphate compound in prebiotic chemistry that played the role of adenosine triphosphate and that the first living organisms had ribose-phosphate in the backbone of their genetic material. However, there are no known efficient prebiotic synthesis of high-energy phosphates or phosphate esters. We review the occurrence of phosphates in nature, the efficiency of the volcanic synthesis of P4O10, the efficiency of polyphosphate synthesis by heating phosphate minerals under geological conditions, and the use of high-energy organic compounds such as cyanamide or hydrogen cyanide. These are shown to be inefficient processes especially when the hydrolysis of the polyphosphates is taken into account. For example, if a whole atmosphere of methane or carbon monoxide were converted to cyanide which somehow synthesized polyphosphates quantitatively, the polyphosphate concentration in the ocean would still have been insignificant. We also attempted to find more efficient high-energy polymerizing agents by spark discharge syntheses, but without success. There may still be undiscovered robust prebiotic syntheses of polyphosphates, or mechanisms for concentrating them, but we conclude that phosphate esters may not have been constituents of the first genetic material. Phosphoanhydrides are also unlikely as prebiotic energy sources.

The effect of two bleaching agents on the phosphate concentration of the enamel evaluated by Raman spectroscopy: An ex vivo study

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Sokkalingam Mothilal Venkatesan

2012-01-01

Full Text Available Aim : The aim of this ex vivo study was to evaluate the effect of in-office bleaching agents,-35% and 38% hydrogen peroxide containing bleaching agents, on the phosphate concentration of the enamel evaluated by Raman spectroscopy. Materials and Methods : Forty noncarious, craze-free human maxillary incisors, extracted for periodontal reasons, were used in this study. Baseline Raman spectra from each specimen were obtained before the application of the bleaching agent to assess the phosphate content present in the teeth. The teeth were divided into two groups: Group A - bleached with pola office bleach (35% hydrogen peroxide, potassium nitrate (light activated. Group B - bleached with opalescence Xtra bleach (38% hydrogen peroxide potassium nitrate and fluoride (chemical activated. After the bleaching procedure, the treated specimens were taken to obtain Raman spectra to assess the phosphate loss after bleaching treatment. Results : The results showed that the chemically activated bleaching agent showed less phosphate loss when compared with the light activated bleaching agent. Conclusion : Within the limitations of this study, it can be concluded that the chemically activated bleaching agent showed minimal phosphate loss when compared to light activated bleaching agent. The chemically activated bleaching agent was better than the light activated bleaching agent when values were evaluated statistically.

INTERACTIONS AMONG PHOSPHATE AMENDMENTS, MICROBES AND URANIUM MOBILITY IN CONTAMINATED SEDIMENTS

Energy Technology Data Exchange (ETDEWEB)

Knox, A

2007-08-30

The use of sequestering agents for the transformation of radionuclides in low concentrations in contaminated soils/sediments offers considerable potential for long-term environmental cleanup. This study evaluated the influence of four phosphate amendments and two microbial amendments on U availability. The synchrotron X-ray fluorescence mapping of the untreated U-contaminated sediment showed that U was closely associated with Mn. All tested phosphate amendments reduced aqueous U concentration more than 90%, likely due to formation of insoluble phosphate precipitates. The addition of A. piechaudii and P. putida alone were found to reduce U concentrations 63% and 31% respectively. Uranium sorption in phosphate treatments was significantly reduced in the presence of microbes. However, increased microbial activity in the treated sediment led to reduction of phosphate effectiveness. The average U concentration in 1 M MgCl{sub 2} extract from U amended sediment was 437 {micro}g/kg, but in the same sediment without microbes (autoclaved sediment), the extractable U concentration was only 103 {micro}g/kg. When the autoclaved amended sediment was treated with autoclaved biological apatite, U concentration in the 1 M MgCl{sub 2} extract was {approx}0 {micro}g/kg. Together these tests suggest that microbes may enhance U leaching and reduce phosphate amendment remedial effectiveness.

Comparative study on in vitro biocompatibility of synthetic octacalcium phosphate and calcium phosphate ceramics used clinically.

Science.gov (United States)

Morimoto, Shinji; Anada, Takahisa; Honda, Yoshitomo; Suzuki, Osamu

2012-08-01

The present study was designed to investigate the extent to which calcium phosphate bone substitute materials, including osteoconductive octacalcium phosphate (OCP), display cytotoxic and inflammatory responses based on their dissolution in vitro. Hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) ceramics, which are clinically used, as well as dicalcium phosphate dihydrate (DCPD) and synthesized OCP were compared. The materials were well characterized by chemical analysis, x-ray diffraction and Fourier transform infrared spectroscopy. Calcium and phosphate ion concentrations and the pH of culture media after immersion of the materials were determined. The colony forming rate of Chinese hamster lung fibroblasts was estimated with extraction of the materials. Proliferation of bone marrow stromal ST-2 cells and inflammatory cytokine TNF-α production by THP-1 cells grown on the material-coated plates were examined. The materials had characteristics that corresponded to those reported. DCPD was shown to dissolve the most in the culture media, with a marked increase in phosphate ion concentration and a reduction in pH. ST-2 cells proliferated well on the materials, with the exception of DCPD, which markedly inhibited cellular growth. The colony forming capacity was the lowest on DCPD, while that of the other calcium phosphates was not altered. In contrast, TNF-α was not detected even in cells grown on DCPD, suggesting that calcium phosphate materials are essentially non-inflammatory, while the solubility of the materials can affect osteoblastic and fibroblastic cellular attachment. These results indicate that OCP is biocompatible, which is similar to the materials used clinically, such as HA. Therefore, OCP could be clinically used as a biocompatible bone substitute material.

Behaviour of the pH adjustment, Ion exchange and concentrate precipitation stages in the acid leaching of uranium phosphate ores

International Nuclear Information System (INIS)

Estrada Aguilar, J.; Uriarte Hueda, A.

1962-01-01

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

Microradioimmunoassay for antibodies to tumor-associated antigens

International Nuclear Information System (INIS)

Huang, J.C.C.; Berczi, I.; Froese, G.; Tsay, H.M.; Sehon, A.H.

1975-01-01

A versatile microradioimmunoassay for the detection of antibodies to tumor-associated and other tissue antigens was described. The method involved: the preparation of solid-phase antigen with cultured (already adhered) or noncultured cells (sedimented by centrifugation) fixed to Micro-Test plates with neutral buffered formaldehyde or absolute methanol; the incubation of the antigen with test or control sera; and the incubation of the antigen with radioiodinated antiglobulin antibody. The nonspecific background of radioactivity was reduced to an acceptable level by the fixed cells being precoated in the wells with 0.5 percent bovine serum albumin in phosphate-buffered saline which was also used for the dilution of sera and labeled antiglobulin antibody. Tumor cells in primary cultures gave a high background, as compared to long-term cultures, which was due to the presence of immunoglobulins (most likely tumor-specific antibody). The specific antibody response to a syngeneic mouse tumor was demonstrated by this technique. (auth)

Selenium Supplementation does not Decrease Thyroid Peroxidase Antibody Concentration in Children and Adolescents with Autoimmune Thyroiditis

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W. Bonfig

2010-01-01

Full Text Available In adults, selenium supplementation decreases thyroid peroxidase antibody (TPO Ab concentrations in patients with autoimmune thyroiditis (AIT. Our aim in this study was to investigate if selenium supplementation decreased TPO Ab and thyroglobulin antibody (Tg Ab concentrations in children with AIT. Forty-nine patients (33 females with newly diagnosed AIT and hypothyroidism were randomized to daily oral therapy with levothyroxine alone (group A, n = 18, levothyroxine plus 100 µg sodium-selenite (group B, n = 13, or levothyroxine plus 200 µg sodium-selenite (group C, n = 18. Mean age at diagnosis was 12.2 ± 2.2 years. All 49 patients needed a mean levothyroxine dose of 1.6 ± 0.5 µg/kg body weight to lower TSH to the treatment goal of 1–2 µU/ml, with no significant difference between groups. At study entry and after 12 months, TPO Ab concentrations were comparable in all three groups. Tg Ab concentrations decreased significantly after 12 months in group A and group C (p = 0.03 and p = 0.01, but not in group B (p = 0.06. It is our conclusion that selenium supplementation with sodium-selenite does not decrease TPO Ab concentrations in children and adolescents, neither given in the reduced dose of 100 µg daily nor given in the “adult” supplementation dose of 200 µg daily.

Data on subgroup specific baseline characteristics and serum sphingosine-1-phosphate concentrations in the Study of Health in Pomerania

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Eileen Moritz

2017-06-01

Full Text Available In this data article, we provide subgroup specific baseline characteristics and serum sphingosine-1-phosphate (S1P concentrations for healthy individuals within the Study of Health in Pomerania (SHIP-TREND cohort. After exclusion of subjects with cardiovascular disease, diabetes mellitus, hypertension, metabolic syndrome, elevated liver enzymes and/or chronic kidney disease stadium III or IV, four subgroups were defined according to different limits for body mass index (BMI, alterations in blood lipid levels and smoking status. Tables show respective clinical and laboratory parameters stratified by gender. Serum S1P concentrations are also stratified by age groups. The data presented herein is related to the research article entitled “Reference intervals for serum sphingosine-1-phosphate in the population-based Study of Health in Pomerania” (E. Moritz, D. Wegner, S. Groß, M. Bahls, M. Dörr, S.B. Felix, T. Ittermann, S. Oswald, M. Nauck, N. Friedrich, R.H. Böger, G. Daum, E. Schwedhelm, B.H. Rauch, Clin Chim Acta. 468 (2017 25–31 [1].

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

Stratification of Antibody-Positive Subjects by Antibody Level Reveals an Impact of Immunogenicity on Pharmacokinetics

OpenAIRE

Zhou, Lei; Hoofring, Sarah A.; Wu, Yu; Vu, Thuy; Ma, Peiming; Swanson, Steven J.; Chirmule, Narendra; Starcevic, Marta

2012-01-01

The availability of highly sensitive immunoassays enables the detection of antidrug antibody (ADA) responses of various concentrations and affinities. The analysis of the impact of antibody status on drug pharmacokinetics (PK) is confounded by the presence of low-affinity or low-concentration antibody responses within the dataset. In a phase 2 clinical trial, a large proportion of subjects (45%) developed ADA following weekly dosing with AMG 317, a fully human monoclonal antibody therapeutic....

High Concentrations of Measles Neutralizing Antibodies and High-Avidity Measles IgG Accurately Identify Measles Reinfection Cases

Science.gov (United States)

Rota, Jennifer S.; Hickman, Carole J.; Mercader, Sara; Redd, Susan; McNall, Rebecca J.; Williams, Nobia; McGrew, Marcia; Walls, M. Laura; Rota, Paul A.; Bellini, William J.

2016-01-01

In the United States, approximately 9% of the measles cases reported from 2012 to 2014 occurred in vaccinated individuals. Laboratory confirmation of measles in vaccinated individuals is challenging since IgM assays can give inconclusive results. Although a positive reverse transcription (RT)-PCR assay result from an appropriately timed specimen can provide confirmation, negative results may not rule out a highly suspicious case. Detection of high-avidity measles IgG in serum samples provides laboratory evidence of a past immunologic response to measles from natural infection or immunization. High concentrations of measles neutralizing antibody have been observed by plaque reduction neutralization (PRN) assays among confirmed measles cases with high-avidity IgG, referred to here as reinfection cases (RICs). In this study, we evaluated the utility of measuring levels of measles neutralizing antibody to distinguish RICs from noncases by receiver operating characteristic curve analysis. Single and paired serum samples with high-avidity measles IgG from suspected measles cases submitted to the CDC for routine surveillance were used for the analysis. The RICs were confirmed by a 4-fold rise in PRN titer or by RT-quantitative PCR (RT-qPCR) assay, while the noncases were negative by both assays. Discrimination accuracy was high with serum samples collected ≥3 days after rash onset (area under the curve, 0.953; 95% confidence interval [CI], 0.854 to 0.993). Measles neutralizing antibody concentrations of ≥40,000 mIU/ml identified RICs with 90% sensitivity (95% CI, 74 to 98%) and 100% specificity (95% CI, 82 to 100%). Therefore, when serological or RT-qPCR results are unavailable or inconclusive, suspected measles cases with high-avidity measles IgG can be confirmed as RICs by measles neutralizing antibody concentrations of ≥40,000 mIU/ml. PMID:27335386

Estimating spatio-temporal dynamics of stream total phosphate concentration by soft computing techniques.

Science.gov (United States)

Chang, Fi-John; Chen, Pin-An; Chang, Li-Chiu; Tsai, Yu-Hsuan

2016-08-15

This study attempts to model the spatio-temporal dynamics of total phosphate (TP) concentrations along a river for effective hydro-environmental management. We propose a systematical modeling scheme (SMS), which is an ingenious modeling process equipped with a dynamic neural network and three refined statistical methods, for reliably predicting the TP concentrations along a river simultaneously. Two different types of artificial neural network (BPNN-static neural network; NARX network-dynamic neural network) are constructed in modeling the dynamic system. The Dahan River in Taiwan is used as a study case, where ten-year seasonal water quality data collected at seven monitoring stations along the river are used for model training and validation. Results demonstrate that the NARX network can suitably capture the important dynamic features and remarkably outperforms the BPNN model, and the SMS can effectively identify key input factors, suitably overcome data scarcity, significantly increase model reliability, satisfactorily estimate site-specific TP concentration at seven monitoring stations simultaneously, and adequately reconstruct seasonal TP data into a monthly scale. The proposed SMS can reliably model the dynamic spatio-temporal water pollution variation in a river system for missing, hazardous or costly data of interest. Copyright © 2016 Elsevier B.V. All rights reserved.

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

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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

Characterisation of phosphate rocks at kurun mountain, Sudan

International Nuclear Information System (INIS)

Abdelgader, G. A. M.

2014-08-01

This main objective of this study was to characterise some Sudanese phosphate raw materials collected from Jebel Kurun, located in the eastern part of Nuba Mountain, Western Sudan. The study also aimed to investigate the association between uranium and phosphate and to determine the concentration of some essential elements and trace elements in the phosphate rock. A total of 30 samples were collected from Karun's eastran mountains, near Abujibiha City and have been analyzed for the selected elements using x-ray fluorescence. The obtained results showed that the average concentration of elements was Ca (11.3) and Fe (1.7) as a percentage, while it was Cu (1617.7), Ni (258.4), Pb (185.9), Ti (27.62), V (3779.9), U (160.9), Zn (152.8) and Mn (776.3) in ppm. The average total phosphorus content (analyzed as P O5 %) using UV-visible spectrometer was found to be 30.54%. This could be considered is acceptable percentage for phosphate to be 30.54%. This could be considered is acceptable percentage for phosphate to be used in industrial fertilizers and phosphoric acid production. The average total calcium carbonate was 15.7%. For the elements distribution, uranium found to be more concentrated in the summit of Jebel Kurun, and it displayed a correlation with lead. Furthermore, four groups of association have been noticed, based on elements concentrations.(Author)

Preformed and regenerated phosphate in ocean general circulation models: can right total concentrations be wrong?

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O. Duteil

2012-05-01

Full Text Available Phosphate distributions simulated by seven state-of-the-art biogeochemical ocean circulation models are evaluated against observations of global ocean nutrient distributions. The biogeochemical models exhibit different structural complexities, ranging from simple nutrient-restoring to multi-nutrient NPZD type models. We evaluate the simulations using the observed volume distribution of phosphate. The errors in these simulated volume class distributions are significantly larger when preformed phosphate (or regenerated phosphate rather than total phosphate is considered. Our analysis reveals that models can achieve similarly good fits to observed total phosphate distributions for a~very different partitioning into preformed and regenerated nutrient components. This has implications for the strength and potential climate sensitivity of the simulated biological carbon pump. We suggest complementing the use of total nutrient distributions for assessing model skill by an evaluation of the respective preformed and regenerated nutrient components.

Fe++/Fe+++ concentration relationship and mechanical properties of phosphate glasses useful for wastes immobilization

International Nuclear Information System (INIS)

Garcia, D.A.; Prado, Miguel O.

2007-01-01

Under different melting conditions, glasses with different Fe(II)/Fe(III) concentration relationship were prepared within each type of glass 43Fe 2 O 3 -57P 2 O 5 and 33,33Fe 2 O 3 - 66,67P 2 O 5 . Using Moessbauer spectroscopy Fe(II)/Fe(III) concentration values were determined. Vickers and Knoop indentations were used for determining their hardness, toughness, Young modulus and brittleness. The same measurements were carried on some silicate and aluminosilicate glasses. Also Weibull statistics was done to determine the characteristics (Weibull modulus and and fracture probability) of glass fracture. We found that silicate glasses (SG) are harder than phosphate glasses (PG). Toughness values for PG, are in the same range than for SG, although for the same density exhibit larger values or smaller brittleness than silicate glasses. For one of the glasses it was found that the mechanical load P 0 needed for a fracture probability of 63% increases with the Fe(II) content. (author)

A novel technique for producing antibody-coated microprobes using a thiol-terminal silane and a heterobifunctional crosslinker.

Science.gov (United States)

Routh, V H; Helke, C J

1997-02-01

Antibody-coated microprobes are used to measure neuropeptide release in the central nervous system. Although they are not quantitative, they provide the most precise spatial resolution of the location of in vivo release of any currently available method. Previous methods of coating antibody microprobes are difficult and time-consuming. Moreover, using these methods we were unable to produce evenly coated antibody microprobes. This paper describes a novel method for the production of antibody microprobes using thiol-terminal silanes and the heterobifunctional crosslinker, 4-(4-N-maleimidophenyl)butyric acid hydrazide HCl 1/2 dioxane (MPBH). Following silation, glass micropipettes are incubated with antibody to substance P (SP) that has been conjugated to MPBH. This method results in a dense, even coating of antibody without decreasing the biological activity of the antibody. Additionally, this method takes considerably less time than previously described methods without sacrificing the use of antibody microprobes as micropipettes. The sensitivity of the microprobes for SP is in the picomolar range, and there is a linear correlation between the log of SP concentration (M) and B/B0 (r2 = 0.98). The microprobes are stable for up to 3 weeks when stored in 0.1 M sodium phosphate buffer with 50 mM NaCl (pH 7.4) at 5 degrees C. Finally, insertion into the exposed spinal cord of an anesthetized rat for 15 min produces no damage to the antibody coating.

TUCS/phosphate mineralization of actinides

Energy Technology Data Exchange (ETDEWEB)

Nash, K.L. [Argonne National Lab., IL (United States)

1997-10-01

This program has as its objective the development of a new technology that combines cation exchange and mineralization to reduce the concentration of heavy metals (in particular actinides) in groundwaters. The treatment regimen must be compatible with the groundwater and soil, potentially using groundwater/soil components to aid in the immobilization process. The delivery system (probably a water-soluble chelating agent) should first concentrate the radionuclides then release the precipitating anion, which forms thermodynamically stable mineral phases, either with the target metal ions alone or in combination with matrix cations. This approach should generate thermodynamically stable mineral phases resistant to weathering. The chelating agent should decompose spontaneously with time, release the mineralizing agent, and leave a residue that does not interfere with mineral formation. For the actinides, the ideal compound probably will release phosphate, as actinide phosphate mineral phases are among the least soluble species for these metals. The most promising means of delivering the precipitant would be to use a water-soluble, hydrolytically unstable complexant that functions in the initial stages as a cation exchanger to concentrate the metal ions. As it decomposes, the chelating agent releases phosphate to foster formation of crystalline mineral phases. Because it involves only the application of inexpensive reagents, the method of phosphate mineralization promises to be an economical alternative for in situ immobilization of radionuclides (actinides in particular). The method relies on the inherent (thermodynamic) stability of actinide mineral phases.

Lipid composition of Chlorella vulgaris (Trebouxiophyceae) as a function of different cadmium and phosphate concentrations

Energy Technology Data Exchange (ETDEWEB)

Chia, Mathias Ahii, E-mail: chia28us@yahoo.com [Department of Botany, Federal University of São Carlos, Rodovia Washington Luis, km 235, São Carlos, SP, Cep 13565905 (Brazil); Department of Biological Sciences, Ahmadu Bello University, Zaria, Nigeria -PMB 1013, Postal Code 810001 (Nigeria); Lombardi, Ana Teresa [Department of Botany, Federal University of São Carlos, Rodovia Washington Luis, km 235, São Carlos, SP, Cep 13565905 (Brazil); Melão, Maria da Graça G. [Department of Hydrobiology, Federal University of São Carlos, Rodovia Washington Luis, km 235, São Carlos, SP, Cep 13565905 (Brazil); Parrish, Christopher C. [Ocean Sciences Centre, Memorial University of Newfoundland, St. John' s, Newfoundland A1C 5S7 (Canada)

2013-03-15

Highlights: ► We studied the effect of Cd and phosphorus (P) on lipids of Chlorella vulgaris. ► Triacylglycerol (TAG) concentration increased under P limitation and Cd stress. ► Fatty acids (FA) saturation increased with P limitation and Cd exposure. ► Lower PUFA were obtained under P limitation and Cd stress. ► Combined P limitation/Cd stress increased total lipid production of the microalga. -- Abstract: Fatty acids are the fundamental structural components of membrane lipids, and the degree of saturation of the long hydrocarbon chains in microalgae contributes to regulation of growth, biomass production and reproduction of aquatic consumers. This research aimed at evaluating the effects of cadmium (2 × 10{sup −8}; 10{sup −7} mol L{sup −1} Cd) on lipid class and fatty acid composition of the microalga Chlorella vulgaris under varying phosphate (PO{sub 4}{sup 3−}) concentrations (6.0 × 10{sup −7} to 2.3 × 10{sup −4} mol L{sup −1}). Under PO{sub 4}{sup 3−} limitation and Cd stress, the storage lipid class triacylglycerol (TAG) was the most accumulated among the lipid classes. Fatty acid composition revealed that the degree of saturation increased with increasing Cd stress and PO{sub 4}{sup 3−} limitation. Decreasing PO{sub 4}{sup 3−} and increasing Cd concentrations resulted in higher saturated fatty acid (SAFA) and monounsaturated FA (MUFA) concentrations. Total polyunsaturated FA (PUFA) and ω3 PUFA, and PUFA:SAFA ratios were higher in the control (2.3 × 10{sup −4} mol L{sup −1} PO{sub 4}{sup 3−}) cells than in either PO{sub 4}{sup 3−} limitation or Cd stress, or in the combination of both stresses. Contrasting with all the other PUFAs, 18:2n – 6 increased as PO{sub 4}{sup 3−} limitation increased. A significant positive relationship of PUFAs, acetone mobile polar lipids (AMPL) and phospholipids (PL) with phosphate concentration in the culture media was obtained, while TAG concentrations had a positive association

Impaired Phosphate Tolerance Revealed With an Acute Oral Challenge.

Science.gov (United States)

Turner, Mandy E; White, Christine A; Hopman, Wilma M; Ward, Emilie C; Jeronimo, Paul S; Adams, Michael A; Holden, Rachel M

2018-01-01

Elevated serum phosphate is consistently linked with cardiovascular disease (CVD) events and mortality in the setting of normal and impaired kidney function. However, serum phosphate does not often exceed the upper limit of normal until glomerular filtration rate (GFR) falls below 30 mL/min/m 2 . It was hypothesized that the response to an oral, bioavailable phosphate load will unmask impaired phosphate tolerance, a maladaptation not revealed by baseline serum phosphate concentrations. In this study, rats with varying kidney function as well as normo-phosphatemic human subjects, with inulin-measured GFR (13.2 to 128.3mL/min), received an oral phosphate load. Hormonal and urinary responses were evaluated over 2 hours. Results revealed that the more rapid elevation of serum phosphate was associated with subjects and rats with higher levels of kidney function, greater responsiveness to acute changes in parathyroid hormone (PTH), and significantly more urinary phosphate at 2 hours. In humans, increases in urinary phosphate to creatinine ratio did not correlate with baseline serum phosphate concentrations but did correlate strongly to early increase of serum phosphate. The blunted rise in serum phosphate in rats with CKD was not the result of altered absorption. This result suggests acute tissue deposition may be altered in the setting of kidney function impairment. Early recognition of impaired phosphate tolerance could translate to important interventions, such as dietary phosphate restriction or phosphate binders, being initiated at much higher levels of kidney function than is current practice. © 2017 American Society for Bone and Mineral Research. © 2017 American Society for Bone and Mineral Research.

Effect of humic substances on the precipitation of calcium phosphate

Institute of Scientific and Technical Information of China (English)

SONG Yong-hui; Hermann H. HAHN; Erhard HOFFMANN; Peter G. WEIDLER

2006-01-01

For phosphorus (P) recovery from wastewater, the effect of humic substances (HS) on the precipitation of calcium phosphate was studied. Batch experiments of calcium phosphate precipitation were undertaken with synthetic water that contained 20 mg/L phosphate (as P) and 20 mg/L HS (as dissolved organic carbon, DOC) at a constant pH value in the range of 8.0-10.0. The concentration variations of phosphate, calcium (Ca) and HS were measured in the precipitation process; the crystalline state and compositions of the precipitates were analysed by powder X-ray diffraction (XRD) and chemical methods, respectively. It showed that at solution pH 8.0, the precipitation rate and removal efficiency of phosphate were greatly reduced by HS, but at solution pH ≥9.0,the effect of HS was very small. The Ca consumption for the precipitation of phosphate increased when HS was added; HS was also removed from solution with the precipitation of calcium phosphate. At solution pH 8.0 and HS concentrations ≤ 3.5 mg/L, and at pH ≥ 9.0 and HS concentrations ≤ 10 mg/L, the final precipitates were proved to be hydroxyapatite (HAP) by XRD. The increases of solution pH value and initial Ca/P ratio helped reduce the influence of HS on the precipitation of phosphate.

Formulation of single super phosphate fertilizer from rock phosphate of Hazara, Pakistan

Directory of Open Access Journals (Sweden)

Matiullah Khan

2012-05-01

Full Text Available Phosphorus deficiency is wide spread in soils of Pakistan. It is imperative to explore the potential and economics of indigenous Hazara rock phosphate for preparation of single super phosphate fertilizer. For the subject study rock phosphate was collected from Hazara area ground at 160 mesh level with 26% total P2O5 content for manual preparation of single super phosphate fertilizer. The rock phosphate was treated with various concentrations of sulfuric acid (98.9%, diluted or pure in the field. The treatments comprised of 20 and 35% pure acid and diluted with acid-water ratios of 1:5, 1:2, 1:1 and 2:1 v/v for acidulation at the rate of 60 liters 100 kg-1 rock phosphate. The amount was prior calculated in the laboratory for complete wetting of rock phosphate. A quantity of 150 kg rock phosphate was taken as treatment. The respective amount of acid was applied with the spray pump of stainless steel or poured with bucket. After proper processing, chemical analysis of the products showed a range of available P2O5 content from 9.56 to 19.24% depending upon the amount of acid and its dilution. The results reveal at that 1:1 dilutions gave the highest P2O5 content (19.24%, lowest free acid (6 % and 32% weight increase. The application of acid beyond or below this combination either pure or diluted gave hygroscopic product and higher free acids. The cost incurred upon the manual processing was almost half the prevailing rates in the market. These results lead to conclude that application of sulfuric acid at the rate of 60 liters 100 kg-1 with the dilution of 50% (v/v can yield better kind of SSP from Hazara rock phosphate at lower prices.

The Influence of Electrolytic Concentration on the Electrochemical Deposition of Calcium Phosphate Coating on a Direct Laser Metal Forming Surface

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Qianyue Sun

2017-01-01

Full Text Available A calcium phosphate (CaP coating on titanium surface enhances its biocompatibility, thus facilitating osteoconduction and osteoinduction with the inorganic phase of the human bone. Electrochemical deposition has been suggested as an effective means of fabricating CaP coatings on porous surface. The purpose of this study was to develop CaP coatings on a direct laser metal forming implant using electrochemical deposition and to investigate the effect of electrolytic concentration on the coating’s morphology and structure by X-ray diffraction, scanning electron microscopy, water contact angle analysis, and Fourier transform infrared spectroscopy. In group 10−2, coatings were rich in dicalcium phosphate, characterized to be thick, layered, and disordered plates. In contrast, in groups 10−3 and 10−4, the relatively thin and well-ordered coatings predominantly consisted of granular hydroxyapatite. Further, the hydrophilicity and cell affinity were improved as electrolytic concentration increased. In particular, the cells cultured in group 10−3 appeared to have spindle morphology with thick pseudopodia on CaP coatings; these spindles and pseudopodia strongly adhered to the rough and porous surface. By analyzing and evaluating the surface properties, we provided further knowledge on the electrolytic concentration effect, which will be critical for improving CaP coated Ti implants in the future.

Targeting Fibroblast Growth Factor 23 Signaling with Antibodies and Inhibitors, Is There a Rationale?

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Seiji Fukumoto

2018-02-01

Full Text Available Fibroblast growth factor 23 (FGF23 is a phosphotropic hormone mainly produced by bone. FGF23 reduces serum phosphate by suppressing intestinal phosphate absorption through reducing 1,25-dihydroxyvitamin D and proximal tubular phosphate reabsorption. Excessive actions of FG23 result in several kinds of hypophosphatemic rickets/osteomalacia including X-linked hypophosphatemic rickets (XLH and tumor-induced osteomalacia. While neutral phosphate and active vitamin D are standard therapies for child patients with XLH, these medications have several limitations both in their effects and adverse events. Several approaches that inhibit FGF23 actions including anti-FGF23 antibodies and inhibitors of FGF signaling have been shown to improve phenotypes of model mice for FG23-related hypophosphatemic diseases. In addition, clinical trials indicated that a humanized anti-FGF23 antibody increased serum phosphate and improved quality of life in patients with XLH. Furthermore, circulatory FGF23 is high in patients with chronic kidney disease (CKD. Many epidemiological studies indicated the association between high FGF23 levels and various adverse events especially in patients with CKD. However, it is not known whether the inhibition of FGF23 activities in patients with CKD is beneficial for these patients. In this review, recent findings concerning the modulation of FGF23 activities are discussed.

Soluble CD30 concentrations in ESRD patients with and without panel reactive HLA antibodies.

Science.gov (United States)

Vaidya, Smita; Partlow, David; Barnes, Titus; Thomas, Phillip; Gugliuzza, Kristin

2006-01-01

In this retrospective study we compared accuracy of panel reactive antibodies (PRA) with serum soluble CD30 (sCD30) contents in predicting acute rejection crisis post-renal transplant. Pre-transplant sera from 115 patients were evaluated for their PRA and sCD30 concentrations. All patients received calcineurin inhibitor-based immunosuppressive therapy. Objective measurements for rejection were biopsy-proven acute rejection (AR) episodes within first six months of the transplant. Post-transplant sera of patients with AR were tested for the presence of donor-specific HLA antibodies (DSA). Overall AR rate was 16% (18/115). Patients positive for PRA and sCD30 tests were at significantly higher risk for AVR compared with those patients negative for both the tests (36% vs. 5%, p=0.01). Among negative PRA patients risk for AR was significantly elevated if they were also tested positive for sCD30 concentrations (21% vs. 5%, p=0.04). Of the 18 patients with AR, 14 were positive for sCD30, and 13 of them (93%) developed DSA post-transplant (p=0.001). These data showed that patients positive for sCD30 contents are at high risk for the development of DSA and AR post-transplant regardless of their pre-transplant PRA.

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.

Modification of liposomal concentration in liposome/adenoviral complexes allows significant protection of adenoviral vectors from neutralising antibody, in vitro.

Science.gov (United States)

Steel, Jason C; Cavanagh, Heather M A; Burton, Mark A; Dingwall, Daniel J; Kalle, Wouter H J

2005-06-01

Adenoviral vectors have been commonly used in gene therapy protocols, however the success of their use is often limited by the induction of host immunity to the vector. Following exposure to the adenoviral vector, adenoviral-specific neutralising antibodies are produced which limits further administration. This study examines the efficacy of complexing liposomes to adenovirus for the protection of the adenovirus from neutralising antibodies in an in vitro setting. Dimethyldioctadecylammonium bromide (DDAB)-dioleoyl-l-phosphatidylethanolamine (DOPE) liposomes were bound at varying concentrations to adenovirus to form AL complexes and tested these complexes' ability to prevent adenoviral neutralisation. It is shown that by increasing the concentration of liposomes in the adenoviral-liposome (AL) complexes we can increase the level of immuno-shielding afforded the adenovirus. It is also shown that the increase in liposomal concentration may lead to drawbacks such as increased cytotoxicity and reductions in expression levels.

Lanthanum-modified bentonite: potential for efficient removal of phosphates from fishpond effluents.

Science.gov (United States)

Kurzbaum, Eyal; Raizner, Yasmin; Cohen, Oded; Rubinstein, Guy; Bar Shalom, Oded

2017-06-01

Adsorption has been suggested as an effective method for removing phosphates from agricultural wastewater effluents that contain relatively high phosphate concentrations. The present study focused on the use of a bentonite-lanthanum clay (Phoslock ® ) for reducing the dissolved phosphate concentration in fishpond effluents. Batch experiments with synthetic phosphate-spiked solutions and with fishpond effluents were performed in order to determine adsorption equilibrium isotherms and kinetics as well as to determine the efficiency of Phoslock ® in removing phosphate from these solutions. In the synthetic phosphate-spiked solution, the mean maximum phosphate adsorption capacity was 92 mg Phoslock ® /mg phosphate removal. A ratio of 50, 100, and 200 mg Phoslock ® /mg phosphate removal was found for complete phosphate removal from the fishpond effluents, where higher doses of Phoslock ® led to a faster removal rate (94% removal within the first 150 min). These results show that bentonite-lanthanum clay can be employed for designing a treatment process for efficient phosphate removal from fishpond effluents.

The antimicrobial activity of as-prepared silver-loaded phosphate glasses and zirconium phosphate

International Nuclear Information System (INIS)

Jing, Wang; Jiang, Ji Zhi; Yang, Yang; Yan, Zhao Chun; Yan, Wang Xiao; He, Shui Zhong

2016-01-01

The antimicrobial activities of silver-loaded zirconium phosphate (JDG) and silver-loaded phosphate glasses (ZZB) against Escherichia coli were studied. Although the silver content in JDG was higher than that in ZZB, ZZB suspensions showed better antimicrobial property than JDG suspensions, especially at low concentrations. The antimicrobial activity was analyzed using minimum inhibitory concentrations, bacterial inhibition ring tests, and detection of silver ions in the suspensions. Furthermore, the amounts of silver ions in suspensions with/without bacterial cells were analyzed. Results revealed that only a portion of released silver ions could be adsorbed by E. coli cells, which are critical to cell death. The damaged microstructures of E. coli cells observed by transmission electron microscopy may further prove that the adsorbed silver ions play an important role in the antimicrobial process.

Procedure for the separation of cerium from rare earth phosphate mixtures

International Nuclear Information System (INIS)

Richter, H.; Grauss, H.; Schmitt, A.; Schade, H.; Lindeholz, M.; Lorenz, E.; Weickart, J.

1986-01-01

The invention is concerned with a procedure for the separation of cerium from rare earth concentrates originating from the partial neutralization of nitric crude phosphate decomposition solutions without preceding elimination of impurities from the raw material. The rare earth phosphates are treated with an excess of concentrated nitric acid through which the Ce 3+ , contained in the solution, is oxidized to Ce 4+ and precipitated as cerium(IV) phosphate by neutralization with alkalis

Radioimmunoassay with heterologous antibody (hetero-antibody RIA)

International Nuclear Information System (INIS)

Iwasawa, Atsushi; Hayashi, Hiroaki; Itoh, Zen; Wakabayashi, Katsumi

1991-01-01

To develop a homologous radioimmunoassay (RIA) for a hormone of a small or rare animal often meets difficulty in collecting a large amount of purified antigen required for antibody production. On the other hand, to employ a heterologous RIA to estimate the hormone often gives poor sensitivity. To overcome this difficulty, a 'hetero-antibody' RIA was studied. In a hetero-antibody RIA system, a purified preparation of a hormone is used for radioiodination and standardization and a heterologous antibody to the hormone is used for the first antibody. Canine motilin and rat LH were selected as examples, and anti-porcine motilin and anti-hCG, anti-hCGβ or anti-ovine LHβ was used as the heterologous antibody. The sensitivities of the hetero-antibody RIAs were much higher than those of heterologous RIAs in any case, showing that these hetero-antibody RIA systems were suitable for practical use. To clarify the principle of hetero-antibody RIA, antiserum to porcine motilin was fractionated on an affinity column where canine motilin was immobilized. The fraction bound had greater constants of affinity with both porcine and canine motilins than the rest of the antibody fractions. This fraction also reacted with a synthetic peptide corresponding to the C-terminal sequence common to porcine and canine motilins in a competitive binding test with labeled canine motilin. These results suggest that an antibody population having high affinity and cross-reactivity is present in polyclonal antiserum and indicate that the population can be used in hetero-antibody RIA at an appropriate concentration. (author)

Uranium and heavy metals in phosphate fertilizers

International Nuclear Information System (INIS)

Khater, A.E.M.

2008-01-01

Agricultural applications of chemical fertilizers are a worldwide practice. The specific activity of uranium-238 and heavy metals in phosphate fertilizers depends on the phosphate ore from which the fertilizer produced and on the chemical processing of the ore. Composite phosphate fertilizers samples where collected and the uranium-238 specific activity, in Bq/kg, and As, Cd, Cu, Pb, Se concentration, in ppm, were measured. The annual addition of these elements in soil due to fertilization were calculated and discussed. (author)(tk)

Uranium and heavy metals in phosphate fertilizers

International Nuclear Information System (INIS)

Khater, Ashraf E.M.; King Saud University, Riyadh

2008-01-01

Full text: Agricultural applications of chemical fertilizers are a worldwide practice. The specific activity of uranium-238 and heavy metals in phosphate fertilizers depends on the phosphate ore from which the fertilizer produced and on the chemical processing of the ore. Composite phosphate fertilizers samples were collected and the uranium-238 specific activity, in Bq/kg, and As, Cd, Cu, Pb, Se concentration were measured. The annual addition of these elements in soil due to soil fertilization were calculated and discussed. (author)

A two-year monitoring study on anionic detergent, phosphate and ...

African Journals Online (AJOL)

Anionic detergent, phosphate and chlorophyll-a concentrations were evaluated in Istanbul Strait between January 2013 and December 2014. Water samples were taken monthly at one station in the strait. The average concentrations of phosphate were 1.38 mg L-1 for surface water and 1.76 mg L -1 for bottom water in 2013 ...

A highly phosphorylated subpopulation of insulin-like growth factor II/mannose 6-phosphate receptors is concentrated in a clathrin-enriched plasma membrane fraction

International Nuclear Information System (INIS)

Corvera, S.; Folander, K.; Clairmont, K.B.; Czech, M.P.

1988-01-01

Insulin-like growth factor II (IGF-II)/mannose 6-phosphate (Man-6-P) receptors immunoprecipitated from purified plasma membranes of 32 P-labeled rat adipocytes are markedly heterogenous in their phosphorylation state. Approximately 80% of the plasma membrane receptors are solubilized in 1% (vol/vol) Triton X-100 and are phosphorylated on serine residues at a stoichiometry of ∼ 0.1-0.2 mol of phosphate per mol of receptor. In contrast, 15-20% of the receptors are Triton X-100-insoluble and are phosphorylated on serine and threonine residues at ∼ 4 or 5 mol of phosphate per mol of receptor. This Triton X-100-insoluble membrane subfraction contains only 5% of the total plasma membrane protein and yet contains all of the clathrin heavy chain associated with plasma membrane. Based on the relative yields of protein in the detergent-insoluble material, IGF-II/Man-6-P receptors are concentrated ∼ 3-fold in this clathrin-enriched subfraction. Taken together, these results indicate that insulin decreases the phosphorylation state of a highly phosphorylated subpopulation of IGF-II/Man-6-P receptors on the plasma membrane. In addition, insulin action may prevent the concentration of these receptors in a clathrin-enriched membrane subfraction

A phosphate-starvation-inducible outermembrane protein of Pseudomonas fluorescens Ag1 as an immunological phosphate-starvation marker

DEFF Research Database (Denmark)

Leopold, Kristine; Jacobsen, Susanne; Nybroe, Ole

1997-01-01

A phosphate-starvation-inducible outer-membrane protein of Pseudomonas fluorescens Ag1, expressed at phosphate concentrations below0.08-0.13 mM, was purified and characterized. The purification method involved separation of outer-membrane proteins by SDS-PAGE andextraction of the protein from...... nitrocellulose or PVDF membranes after electrotransfer of proteins to the membranes. The N-terminal amino acidsequence of the purified protein, called Psi1, did not show homology to any known proteins, and in contrast to the phosphate-specific porin OprP ofP. aeruginosa its mobility in SDS-PAGE was not affected...

Pharmacokinetics and concentration-effect relationships of therapeutic monoclonal antibodies and fusion proteins.

Science.gov (United States)

Ternant, David; Paintaud, Gilles

2005-09-01

Although monoclonal antibodies (mAbs) constitute a major advance in therapeutics, their pharmacokinetic (PK) and pharmacodynamic (PD) properties are not fully understood. Saturable mechanisms are thought to occur in distribution and elimination of mAbs, which are protected from degradation by the Brambell's receptor (FcRn). The binding of mAbs to their target antigen explains part of their nonlinear PK and PD properties. The interindividual variability in mAb PK can be explained by several factors, including immune response against the biodrug and differences in the number of antigenic sites. The concentration-effect relationships of mAbs are complex and dependent on their mechanism of action. Interindividual differences in mAb PD can be explained by factors such as genetics and clinical status. PK and concentration-effect studies are necessary to design optimal dosing regimens. Because of their above-mentioned characteristics, the interindividual variability in their dose-response relationships must be studied by PK-PD modelling.

Phosphate, urea and creatinine clearances: haemodialysis adequacy assessed by weekly monitoring.

Science.gov (United States)

Debowska, Malgorzata; Wojcik-Zaluska, Alicja; Ksiazek, Andrzej; Zaluska, Wojciech; Waniewski, Jacek

2015-01-01

The specific distribution of phosphate and the control mechanisms for its plasma level makes phosphate kinetics during haemodialysis (HD) considerably different from those of urea and creatinine and makes the quantitative evaluation of adequacy of phosphate removal difficult. We propose the application of equivalent continuous clearance (ECC) as a phosphate adequacy parameter and compare it with ECC for creatinine and urea. Three consecutive dialysis sessions were evaluated for 25 patients on maintenance HD. Concentrations of phosphate, urea and creatinine in plasma were measured every 1h during the treatment and 45 min after, and every 30 min in dialysate. ECC was calculated using the removed solute mass assessed in dialysate and weekly solute profile in plasma. Similar calculations were performed also for the midweek dialysis session only. Different versions of the reference concentration for ECC were applied. ECC with peak average reference concentration was 5.4 ± 1.0 for phosphate, 7.0 ± 1.0 for urea and 4.7 ± 1.0 mL/min for creatinine. ECC for urea and creatinine were well correlated in contrast to the correlations of ECC for phosphate versus urea and creatinine. Midweek ECC were higher than weekly ECC, but they were well correlated for urea and creatinine, but only weakly for phosphate. HD adequacy monitoring for phosphate may be performed using ECC, but it is less predictable than similar indices for urea and creatinine. The values of ECC for phosphate are within the range expected for its molecular size compared with those for urea and creatinine. © The Author 2014. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

PHOSPHATES REMOVAL FROM REJECT WATER FROM DIGESTION OF SLUDGE

Directory of Open Access Journals (Sweden)

Elżbieta Sperczyńska

2016-06-01

Full Text Available The aim of the research work was to evaluate if coagulants used on technical scale are useful in phosphates removal from reject water. Effectiveness of phosphorus compounds removal from reject water from digestion of sewage sludge was examined. Selected prehydrolysed alkaline aluminium polychlorides were used. The results were compared to the ones obtained with aluminium sulphate. Reject water from digestion of sewage sludge form WWTP of 100 000 PE were examined. Commercial agents – prehydrolysed PAX 18, PAX XL10, PAX-XL1905 as well as aluminium sulphate were used. Various doses of coagulants: 0.7; 1.0; 1.5 – time higher than stoichiometric dose were applied. Stoichiometric dose was calculated based on chemical reaction of insoluble aluminium phosphate formation. Concentrations of Kiejdahl nitrogen (891 mgNKj/dm3, phosphates (125 mgPO43-/dm3 and organic compounds - COD (592 mgO2/dm3 in reject water were very high. The effectiveness of coagulation process increased as the doses of chemical agents increased. The most effective doses were the highest ones used during the experiment. The most effective agent was PAX 18 (96% removal efficiency. As the phosphates concentration decreased COD content declined simultaneously. Maximum COD removal (47% was obtained when highly alkaline PAX XL 1905 was used. Use of the lowest dose of Al2(SO43 allowed for 50% phosphates removal, whereas the lowest dose of PAX 18 decreased phosphates concentration by 83%.

Estimated exposures to perfluorinated compounds in infancy predict attenuated vaccine antibody concentrations at age 5-years

DEFF Research Database (Denmark)

Grandjean, Philippe; Heilmann, Carsten; Weihe, Pal

2017-01-01

Perfluorinated alkylate substances (PFASs) are highly persistent and may cause immunotoxic effects. PFAS-associated attenuated antibody responses to childhood vaccines may be affected by PFAS exposures during infancy, where breastfeeding adds to PFAS exposures. Of 490 members of a Faroese birth...... cohort, 275 and 349 participated in clinical examinations and provided blood samples at ages 18 months and 5 years. PFAS concentrations were measured at birth and at the clinical examinations. Using information on duration of breastfeeding, serum-PFAS concentration profiles during infancy were estimated......, with decreases by up to about 20% for each two-fold higher exposure, while associations for serum concentrations at ages 18 months and 5 years were weaker. Modeling of serum-PFAS concentration showed levels for age 18 months that were similar to those measured. Concentrations estimated for ages 3 and 6 months...

Gastric Cancer Screening by Combined Determination of Serum Helicobacter pylori Antibody and Pepsinogen Concentrations: ABC Method for Gastric Cancer Screening

Directory of Open Access Journals (Sweden)

Xian-Zhe Chen

2018-01-01

Conclusions: The early detection and diagnosis of gastric cancer benefit from the risk stratification, but the cutoff values for H. pylori antibody and serum PG concentration require further modification.

Calcium phosphate saturation in the western Bay of Bengal

Digital Repository Service at National Institute of Oceanography (India)

Naik, S.; Reddy, C.V.G.

Temperature, inorganic phosphate concentration and pH seem to be the major factors influencing the degree of saturation of calcium phosphate in sea water. Two water regions can be demarcated in the study area based on the saturation patterns...

Global radiological impact of the phosphate fertilizers

International Nuclear Information System (INIS)

Morales, Rudnei Karam; Alves, Rex Nazare

1996-01-01

About ninety percent of the products obtained in the phosphate industry are directly used in agriculture as fertilizers. The uranium, thorium and radium content in phosphate fertilizers pollute the soil, water and air, creating risks due to associated natural radiation. This work shows the concentration of radionuclides present in various products of the national and American phosphate fertilizers industry, and compared them with worldwide mean values. The radiological impact of the products on the environment is evaluated and suggestions are presented in order to minimize the risks due to radioactivity. (author)

Stability of monoclonal antibodies at high-concentration

DEFF Research Database (Denmark)

Neergaard, Martin S; Nielsen, Anders D; Parshad, Henrik

2014-01-01

Few studies have so far directly compared the impact of antibody subclass on protein stability. This case study investigates two mAbs (one IgG1 and one IgG4 ) with identical variable region. Investigations of mAbs that recognize similar epitopes are necessary to identify possible differences betw...

Co-precipitation of phosphate and iron limits mitochondrial phosphate availability in Saccharomyces cerevisiae lacking the yeast frataxin homologue (YFH1).

Science.gov (United States)

Seguin, Alexandra; Santos, Renata; Pain, Debkumar; Dancis, Andrew; Camadro, Jean-Michel; Lesuisse, Emmanuel

2011-02-25

Saccharomyces cerevisiae cells lacking the yeast frataxin homologue (Δyfh1) accumulate iron in the mitochondria in the form of nanoparticles of ferric phosphate. The phosphate content of Δyfh1 mitochondria was higher than that of wild-type mitochondria, but the proportion of mitochondrial phosphate that was soluble was much lower in Δyfh1 cells. The rates of phosphate and iron uptake in vitro by isolated mitochondria were higher for Δyfh1 than wild-type mitochondria, and a significant proportion of the phosphate and iron rapidly became insoluble in the mitochondrial matrix, suggesting co-precipitation of these species after oxidation of iron by oxygen. Increasing the amount of phosphate in the medium decreased the amount of iron accumulated by Δyfh1 cells and improved their growth in an iron-dependent manner, and this effect was mostly transcriptional. Overexpressing the major mitochondrial phosphate carrier, MIR1, slightly increased the concentration of soluble mitochondrial phosphate and significantly improved various mitochondrial functions (cytochromes, [Fe-S] clusters, and respiration) in Δyfh1 cells. We conclude that in Δyfh1 cells, soluble phosphate is limiting, due to its co-precipitation with iron.

[Effect of Photodynamic Inactivation (PDI) using Riboflavin-Conjugated Antibody against Staphylococcus aureus].

Science.gov (United States)

Song, X; Stachon, T; Seitz, B; Wang, J; Bischoff, M; Langenbucher, A; Janunts, E; Szentmáry, N

2015-08-01

Crosslinking/riboflavin-UVA photodynamic therapy is a potential treatment alternative in antibiotic resistant infectious keratitis. For photodynamic therapy a specific (against bacteria) conjugated antibody may be used in order to increase the effect of the treatment. In our present study we analysed the impact of photodynamic inactivation using riboflavin-conjugated antibody or riboflavin alone on Staphylococcus aureus, in vitro. Staphylococcus aureus (S. aureus) was incubated in 1 : 100 diluted riboflavin-conjugated antibody (R-AB) for 30 minutes in darkness. Following UVA-light illumination (375 nm) with an energy dose of 2, 3, 4 and 8 J/cm(2), bacteria were brought to blood agar Plates for 24 hours before colony-forming unit (CFU) counting. In an additional group, we incubated bacteria to 0, 0.05 or 0.1 % riboflavin 5-phosphate as described above followed by illumination using UVA light (375 nm) with an energy dose of 2 J/cm(2), before CFU counting. The number of CFU decreased significantly (inactivation of 36 %, p = 0.022) using 1 : 100 diluted riboflavin-conjugated antibody and 2 J/cm(2) UVA-light illumination, compared to untreated controls. The use of 3, 4 und 8 J/cm(2) energy dose and R-AB in 1 : 100 dilution did not further change the decrease of CFU (inactivation of 39, 39 and 40 %; p = 0.016; p = 0.016; p = 0.015). The use of 0.05 % or 0.1 % riboflavin 5-phosphate alone and UVA-light illumination reduced the CFU count significantly (inactivation of 73 and 55 %; p = 0.002; p = 0.005), compared to untreated controls. The use of riboflavin-conjugated antibody or 0.05 % or 0.1 % riboflavin 5-phosphate and UVA-light illumination reduces the number of CFU of S. aureus. However, none of these photodynamic therapies reached the necessary 99 % killing rate of these bacteria. Further work is needed to increase the efficacy of riboflavin-conjugated antibodies against antibiotic resistant bacteria. Georg

Development of chemically engineered porous metal oxides for phosphate removal

International Nuclear Information System (INIS)

Delaney, Paul; McManamon, Colm; Hanrahan, John P.; Copley, Mark P.; Holmes, Justin D.; Morris, Michael A.

2011-01-01

In this study, the application of ordered mesoporous silica (OMS) doped with various metal oxides (Zr, Ti, Fe and Al) were studied for the removal of (ortho) phosphate ions from water by adsorption. The materials were characterized by means of N 2 physisorption (BET), powder X-ray diffraction (PXRD) and transmission electron microscopy (TEM). The doped materials had surface areas between 600 and 700 m 2 g -1 and exhibited pore sizes of 44-64 A. Phosphate adsorption was determined by measurement of the aqueous concentration of orthophosphate using ultraviolet-visible (UV-vis) spectroscopy before and after extraction. The effects of different metal oxide loading ratios, initial concentration of phosphate solution, temperature and pH effects on the efficiency of phosphate removal were investigated. The doped mesoporous materials were effective adsorbents of orthophosphate and up to 100% removal was observed under appropriate conditions. 'Back extracting' the phosphate from the doped silica (following water treatment) was also investigated and shown to have little adverse effect on the adsorbent.

Phosphate-rich sedimentary rocks: significance for organic facies and petroleum exploration

Energy Technology Data Exchange (ETDEWEB)

Waples, D W

1982-03-01

Phosphorus-bearing rocks and sediments can be divided into two genetically distinct classes: phosphatic shales or limestones and phosphorites. Phosphatic shales are primary sediments in which phosphate nodules or micronodules have formed diagenetically by precipitation of calcium phosphates derived mainly from organic phosphorus. The nodules form in reducing environments at shallow depths within the sediments, where loss of phosphate by diffusion to the overlying water column is minimized. Highly biogenic sediments containing large amounts of organic matter and some fine clastic debris provide ideal environments for the formation of phosphate nodules. Phosphorites, in contrast, represent concentrated accumulations of reworked phosphate nodules which originated in phosphatic shales or limestones. Currents, wave action, recrystallization, and erosion and resedimentation are important mechanisms in the concentration process. Phosphatic shales and limestones may become excellent oil source rocks if thermal maturity is achieved. They are useful facies indicators for anoxic or nearly anoxic depositional environments, and are often associated with restricted basins, or, during certain geologic periods, with broad shelves developed during transgressions. Phosphorites, in contrast, are often correlated with sea-level regressions or uplifts. They are modest source rocks because of their low organic carbon contents and the fact that they were reworked under oxidizing conditions. Nevertheless, because phosphorites are derived from, and often grade into, phosphatic shales, they also are of potential utility in the search for oil source beds.

Biomimetic coprecipitation of calcium phosphate and bovine serum albumin on titanium alloy

NARCIS (Netherlands)

Liu, Yuelian; Layrolle, Pierre; de Bruijn, Joost Dick; van Blitterswijk, Clemens; de Groot, K.

2001-01-01

Titanium alloy implants were precoated biomimetically with a thin and dense layer of calcium phosphate and then incubated either in a supersaturated solution of calcium phosphate or in phosphate-buffered saline, each containing bovine serum albumin (BSA) at various concentrations, under

Sorption of phosphate onto calcite; results from batch experiments and surface complexation modeling

DEFF Research Database (Denmark)

Sø, Helle Ugilt; Postma, Dieke; Jakobsen, Rasmus

2011-01-01

The adsorption of phosphate onto calcite was studied in a series of batch experiments. To avoid the precipitation of phosphate-containing minerals the experiments were conducted using a short reaction time (3h) and low concentrations of phosphate (⩽50μM). Sorption of phosphate on calcite was stud......The adsorption of phosphate onto calcite was studied in a series of batch experiments. To avoid the precipitation of phosphate-containing minerals the experiments were conducted using a short reaction time (3h) and low concentrations of phosphate (⩽50μM). Sorption of phosphate on calcite...... of a high degree of super-saturation with respect to hydroxyapatite (SIHAP⩽7.83). The amount of phosphate adsorbed varied with the solution composition, in particular, adsorption increases as the CO32- activity decreases (at constant pH) and as pH increases (at constant CO32- activity). The primary effect...... of ionic strength on phosphate sorption onto calcite is its influence on the activity of the different aqueous phosphate species. The experimental results were modeled satisfactorily using the constant capacitance model with >CaPO4Ca0 and either >CaHPO4Ca+ or >CaHPO4- as the adsorbed surface species...

Long-term nitrate and phosphate loading of river water in the Upper ...

African Journals Online (AJOL)

High nitrate and phosphate concentrations were recorded directly downstream of residential, municipal and industrial areas suggesting that these were the major sources of the pollutants found in the river water. For example, phosphate concentration at 2 sites along Mukuvisi River (downstream of domestic and industrial ...

Spectroscopic properties of highly Nd-doped lead phosphate glass

Energy Technology Data Exchange (ETDEWEB)

Novais, A.L.F. [Instituto de Física, Universidade Federal de Alagoas, Grupo de Fotônica e Fluidos Complexos, 57072-970 Maceió, AL (Brazil); Dantas, N.O. [Laboratório de Novos Materiais Isolantes e Semicondutores (LNMIS), Instituto de Física, Universidade Federal de Uberlândia, 38400-902 Uberlândia, MG (Brazil); Guedes, I. [Departamento de Física, Universidade Federal do Ceará, Campus do PICI, Caixa Postal 6030, 60455-760 Fortaleza, CE (Brazil); Vermelho, M.V.D., E-mail: vermelho@fis.ufal.br [Instituto de Física, Universidade Federal de Alagoas, Grupo de Fotônica e Fluidos Complexos, 57072-970 Maceió, AL (Brazil)

2015-11-05

The spectroscopic characteristics of highly Nd{sup 3+}-doped lead phosphate glasses (xNd:Pb{sub 3}(PO{sub 4}){sub 2}) have been investigated. The X-ray spectra show that the matrices are glassy up to 25 wt% of Nd{sup 3+} doping. From the Judd–Ofelt analysis we observe that while the Ω{sub (2)} parameter remains constant indicating that the 4f{sup N} and 4f{sup N−1}5 d{sup 1} configurations are not affected by the Nd{sup 3+} doping, the behavior of both Ω{sub (4)} and Ω{sub (6)} changes for 15 wt% of Nd{sup 3+} doping. The reduction of the Ω{sub (6)} parameter is related to the increase of the covalence bonding between the ligands and the Nd{sup 3+} ions. At this particular concentration, the radiative lifetime has a four-fold enhancement. Such behaviors are likely to be related to a modification in the glass structure for high Nd{sup 3+} concentrations. - Graphical abstract: Highly doped lead-phosphate glass matrix, with nominal concentration of up to 25 wt%, maintain the spectroscopic properties without deterioration. The analysis concerning the point of view of Nd{sup 3+} ions showed that high concentrations only affects the rare earth electronic charge density distribution. - Highlights: • Spectroscopic characterization of Nd{sub 2}O{sub 3} highly doped lead phosphate glasses. • Phosphate glass doped with Nd{sup 3+} for applications in photonic devices. • Judd–Ofelt analysis in phosphate glasses doped with Neodymium.

Sorption of uranyl ions on silica. Effects of contact time, pH, ionic strength, concentration and phosphate

International Nuclear Information System (INIS)

Zhang Hongxia; Tao Zuyi

2002-01-01

The sorption of UO 2 2+ and phosphate on silica were simultaneously studied. The effect of contact time between the solid phase and aqueous solution, pH and ionic strength on the UO 2 2+ sorption in the absence and the presence of phosphate was investigated. The effect of contact time between the solid phase and aqueous solution, pH and ionic strength on the phosphate sorption was investigated too. The isotherms of UO 2 2+ and phosphate sorption at different pH values were determined. It was found that as compared with the sorption in the absence of phosphate, the sorption of UO 2 2+ on silica in the presence of phosphate is increased at low pH and decreased at high pH; the abruptly increased with increasing pH in the pH range 3-6; the sorption is gradually decreased with increasing pH in the pH range 2-12; the sorption insensitive and the sorption of phosphate is sensitive to ionic strength. (author)

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.

Effect of Phosphate levels on vegetables irrigated with wastewater

Science.gov (United States)

Oladeji, S. O.; Saeed, M. D.

2018-04-01

This study examined accumulation of phosphate ions in wastewater and vegetables through man-made activities. Phosphate level was determined in wastewater and vegetables collected on seasonal basis along Kubanni stream in Zaria using UV/Visible and Smart Spectro Spectrophotometers for their analyses. Results obtained show that phosphate concentrations ranged from 3.85 – 42.33 mg/L in the first year and 15.60 – 72.80 mg/L in the second year for wastewater whereas the vegetable had levels of 3.80 – 23.65 mg/kg in the year I and 7.48 – 27.15 mg/kg in the year II. Further statistical tests indicated no significant difference in phosphate levels across the locations and seasons for wastewater and vegetables evaluated. Correlation results for these two years indicated negative (r = -0.062) relationship for wastewater while low (r = 0.339) relationship noticed for vegetables planted in year I to that of year II. Phosphate concentrations obtained in this study was higher than Maximum Contaminant Levels set by Standard Organization such as WHO and FAO for wastewater whereas vegetables of the sampling sites were not contaminated with phosphate ions. Irrigating farmland with untreated wastewater has negative consequence on the crops grown with it.

Final Report - Assessment of Potential Phosphate Ion-Cementitious Materials Interactions

International Nuclear Information System (INIS)

Naus, Dan J.; Mattus, Catherine H.; Dole, Leslie Robert

2007-01-01

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

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.

Complex formation of uranium(VI) with fructose and glucose phosphates

International Nuclear Information System (INIS)

Koban, A.; Geipel, G.; Bernhard, G.; Fanghaenel, T.

2002-01-01

The uptake of heavy metals into plants is commonly quantified by the soil-plant transfer factor. Up to now little is known about the chemical speciation of actinides in plants. To compare the obtained spectroscopic data of uranium complexes in plants with model compounds, we investigate the complexation of uranium with relevant bioligands of various functionalities. A very important class of ligands consists of phosphate esters, which serve as phosphate group and energy transmitters as well as energy storage media in biological systems. Heavy metal ions bound to the phosphate esters can be transported into living cells and then deposited. Therefore, in our study we present the results of uranium complexation with glucose-6-phosphate (G6P), and fructose-6-phosphate (F6P) obtained by time-resolved laser-induced fluorescence spectroscopy (TRLFS). The experiments were performed at a fixed uranyl concentration (10 -5 M) as a function of the ligand concentrations (10 -5 to 10 -3 M) in a pH range from 2 to 4.5. For the glucose phosphate system we observed, using increasing ligand concentrations, a decrease in the fluorescence intensity and a small red shift of the emission bands. From this we conclude that the complexed uranyl glucose phosphate species show only minor or no fluorescence properties. The TRLFS spectra of the glucose phosphate samples indicated the presence of a single species with fluorescence properties. This species has a lifetime of approximately 1.5 μs and was identified as the free uranyl ion. An opposite phenomenon was observed for the fructose phosphate system: there was no decrease in fluorescence intensity. However, a strong red shift of the spectra was observed, illustrating the fluorescence properties of the uranyl fructose phosphate complex. The TRLFS spectra of the fructose phosphate system showed a second lifetime ( 2 2+ UO 2 (lig) x (2-y)+ + y H + (lig = sugar phosphate). Applying the mass action law and transformation to the logarithmic

Salivary flow rate, pH, and concentrations of calcium, phosphate, and sIgA in Brazilian pregnant and non-pregnant women

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Lindemann Laura

2006-11-01

Full Text Available Abstract Background Studies on salivary variables and pregnancy in Latin America are scarce. This study aimed to compare salivary flow rate, pH, and concentrations of calcium, phosphate, and sIgA of unstimulated whole saliva in pregnant and non-pregnant Brazilians. Methods Cross-sectional study. Sample was composed by 22 pregnant and 22 non-pregnant women attending the Obstetrics and Gynecology Clinics, São Lucas Hospital, in Porto Alegre city, South region of Brazil. Unstimulated whole saliva was collected to determine salivary flow rate, pH, and biochemical composition. Data were analyzed by Student t test and ANCOVA (two-tailed α = 0.05. Results No difference was found for salivary flow rates and concentrations of total calcium and phosphate between pregnant and non-pregnant women (p > 0.05. Pregnant women had lower pH (6.7 than non-pregnant women (7.5 (p Conclusion Some of the tested variables of unstimulated whole saliva were different between pregnant and non-pregnant Brazilians in this sample. Overall, the values of the tested salivary parameters were within the range of international references of normality.

The influence of pilocarpine and biperiden on pH value and calcium, phosphate, and bicarbonate concentrations in saliva during and after radiotherapy for head and neck cancer.

Science.gov (United States)

Rode, M; smid, L; Budihna, M; Gassperssic, D; Rode, M; Soba, E

2001-11-01

The purpose of the present study was to investigate the influence of parasympathomimetic pilocarpine and anticholinergic biperiden on salivation, pH value, and calcium, phosphate, and bicarbonate concentrations in saliva in patients irradiated for malignant tumors of the head and neck region. Sixty-nine patients were randomly assigned into 3 groups. Group A consisted of patients receiving pilocarpine, group B of those who were receiving biperiden during radiotherapy and pilocarpine for 6 weeks after its completion, and group C comprised patients receiving neither of the mentioned drugs. The quantity of secreted unstimulated saliva, its pH value, as well as calcium, phosphate, and bicarbonate concentrations in saliva were measured before the beginning of radiotherapy, after 30 Gy of irradiation, at completed irradiation, and 3, 6, and 12 months after completion of radiotherapy. Saliva secretion was found to be the least affected in the group of patients receiving biperiden throughout the course of radiotherapy. One year after completion of therapy, the quantity of secreted saliva could only be measured in the patients receiving biperiden during radiotherapy; it amounted to 16% of the average initial quantity of saliva secreted before the beginning of irradiation. In all 3 groups of patients, mean pH value decreased during radiotherapy and started to increase again after completion of irradiation. In group B the decrease in pH value after radiotherapy was statistically significantly smaller than that in group C (P =.01). During and after irradiation, calcium concentration was increased in all 3 groups of patients. Phosphate concentration decreased during radiotherapy in all 3 groups. In group B it started to increase again 3 months after completion of radiotherapy. Bicarbonate concentration showed a slight increase during radiotherapy and started to decrease again after completion of irradiation. The results of our study indicate that the inhibition of saliva

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

Radon Progeny in Egyptian Underground Phosphate Mines

International Nuclear Information System (INIS)

El-Hady, M.A.; Mohammed, A.; El-Hussein, A.; Ali, A.E.; Ahmed, A.A.

2001-01-01

In addition to the workers in uranium mines, the staff of other underground mines, such as workers in underground phosphate mines, can be exposed to 222 Rn and its progeny. In this study the individual radon progeny concentrations were measured in three Egyptian underground phosphate mines to estimate the occupational exposure of the workers at those sites. A filter method was used to measure individual radon progeny concentrations ( 218 Po, 214 Pb and 214 Po). The reported mean values of radon progeny concentrations exceed the action levels which are recommended by ICRP 65 (1993). Based on the measured individual radon progeny concentrations ( 218 Po, 214 Pb and 214 Po) in these mines, the annual effective dose for the workers has been calculated using the lung dose model of ICRP 66 (1994). According to the obtained results, some countermeasures were recommended in this study to minimise these exposure levels. (author)

Microchip Immunoaffinity Electrophoresis of Antibody-Thymidine Kinase 1 Complex

Science.gov (United States)

Pagaduan, Jayson V.; Ramsden, Madison; O’Neill, Kim; Woolley, Adam T.

2015-01-01

Thymidine kinase-1 (TK1) is an important cancer biomarker whose serum levels are elevated in early cancer development. We developed a microchip electrophoresis immunoaffinity assay to measure recombinant purified TK1 (pTK1) using an antibody that binds to human TK1. We fabricated poly(methyl methacrylate) microfluidic devices to test the feasibility of detecting antibody (Ab)-pTK1 immune complexes as a step towards TK1 analysis in clinical serum samples. We were able to separate immune complexes from unbound antibodies using 0.5X phosphate buffer saline (pH 7.4) containing 0.01% Tween-20, with 1% w/v methylcellulose that acts as a dynamic surface coating and sieving matrix. Separation of the antibody and Ab-pTK1 complex was observed within a 5 mm effective separation length. This method of detecting pTK1 is easy to perform, requires only a 10 μL sample volume, and takes just 1 minute for separation. PMID:25486911

Phosphate enhances levan production in the endophytic bacterium Gluconacetobacter diazotrophicus Pal5

Science.gov (United States)

Idogawa, Nao; Amamoto, Ryuta; Murata, Kousaku; Kawai, Shigeyuki

2014-01-01

Gluconacetobacter diazotrophicus is a gram-negative and endophytic nitrogen-fixing bacterium that has several beneficial effects in host plants; thus, utilization of this bacterium as a biofertilizer in agriculture may be possible. G. diazotrophicus synthesizes levan, a D-fructofuranosyl polymer with β-(2→6) linkages, as an exopolysaccharide and the synthesized levan improves the stress tolerance of the bacterium. In this study, we found that phosphate enhances levan production by G. diazotrophicus Pal5, a wild type strain that showed a stronger mucous phenotype on solid medium containing 28 mM phosphate than on solid medium containing 7 mM phosphate. A G. diazotrophicus Pal5 levansucrase disruptant showed only a weak mucous phenotype regardless of the phosphate concentration, indicating that the mucous phenotype observed on 28 mM phosphate medium was caused by levan. To our knowledge, this is the first report of the effect of a high concentration of phosphate on exopolysaccharide production. PMID:24717418

Gastric Cancer Screening by Combined Determination of Serum Helicobacter pylori Antibody and Pepsinogen Concentrations: ABC Method for Gastric Cancer Screening.

Science.gov (United States)

Chen, Xian-Zhe; Huang, Cheng-Zhi; Hu, Wei-Xian; Liu, Ying; Yao, Xue-Qing

2018-05-20

Gastroscopy combined with gastric mucosa biopsies is currently regarded as a gold standard for diagnosis of gastric cancer. However, its application is restricted in clinical practice due to its invasive property. A new noninvasive population screening process combining the assay of anti-Helicobacter pylori antibody and serum pepsinogen (PG) (ABC method) is adopted to recognize the high-risk patients for further endoscopy examination, avoiding the unnecessary gastroscopy for most population and saving the cost consumption for mass screening annually. Nevertheless, controversies exist for the grouping of ABC method and the intervals of gastroscopy surveillance for each group. In this review, we summarized these popular concerned topics for providing useful references to the healthcare practitioner in clinical practice. The PubMed databases were systematically searched from the inception dates to November 22, 2017, using the keywords "Helicobacter pylori," "Pepsinogens," and "Stomach Neoplasms." Original articles and reviews on the topics were selected. Anti-H. pylori antibody and serum PG concentration showed significant changes under the different status of H. pylori infection and the progression of atrophic gastritis, which can be used for risk stratification of gastric cancer in clinic. In addition, anti-H. pylori antibody titer can be used for further risk stratification of gastric cancer contributing to determine better endoscopy surveillance interval. The early detection and diagnosis of gastric cancer benefit from the risk stratification, but the cutoff values for H. pylori antibody and serum PG concentration require further modification.

A generalized quantitative antibody homeostasis model: maintenance of global antibody equilibrium by effector functions.

Science.gov (United States)

Prechl, József

2017-11-01

The homeostasis of antibodies can be characterized as a balanced production, target-binding and receptor-mediated elimination regulated by an interaction network, which controls B-cell development and selection. Recently, we proposed a quantitative model to describe how the concentration and affinity of interacting partners generates a network. Here we argue that this physical, quantitative approach can be extended for the interpretation of effector functions of antibodies. We define global antibody equilibrium as the zone of molar equivalence of free antibody, free antigen and immune complex concentrations and of dissociation constant of apparent affinity: [Ab]=[Ag]=[AbAg]= K D . This zone corresponds to the biologically relevant K D range of reversible interactions. We show that thermodynamic and kinetic properties of antibody-antigen interactions correlate with immunological functions. The formation of stable, long-lived immune complexes correspond to a decrease of entropy and is a prerequisite for the generation of higher-order complexes. As the energy of formation of complexes increases, we observe a gradual shift from silent clearance to inflammatory reactions. These rules can also be applied to complement activation-related immune effector processes, linking the physicochemical principles of innate and adaptive humoral responses. Affinity of the receptors mediating effector functions shows a wide range of affinities, allowing the continuous sampling of antibody-bound antigen over the complete range of concentrations. The generation of multivalent, multicomponent complexes triggers effector functions by crosslinking these receptors on effector cells with increasing enzymatic degradation potential. Thus, antibody homeostasis is a thermodynamic system with complex network properties, nested into the host organism by proper immunoregulatory and effector pathways. Maintenance of global antibody equilibrium is achieved by innate qualitative signals modulating a

Stopped-flow injection method for determination of phosphate in soils and fertilisers

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Jaroon Jakmunee

2008-02-01

Full Text Available A stopped-flow injection system for the determination of phosphate has been developed. It involves the phosphate-molybdate-ascorbic acid reactions in the molybdenum blue method. The system is controlled by a semi-automatic stopped-FI analyser with a light emitting diode (LED-colorimeter for monitoring the absorbance change relating to the concentration of a reaction product formed during the stopping period while the injected zone of a standard or sample is being in the flow cell. The slope of the FIAgram obtained is linearly proportional to the reaction rate, which depends on the phosphate concentration. Effects of concentration of reagents, viz. sodium molybdate, ascorbic acid and nitric acid, on the slope of the FIAgram were studied. The suitable concentration is 0.02 M, 0.25 %w/v and 0.15 M, respectively. A linear calibration graph in the range of 0.3-6.0 mg P L-1 was employed for the determination of phosphate in soil and fertiliser samples. The results obtained agree well with those from a standard spectrophotometric method.

EFFECT OF SODIUM PHOSPHATES ON SELECTED FOOD GRADE BACTERIA

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Stanislav Kráčmar

2011-04-01

Full Text Available The aim of this study was to examine the inhibitory effect in vitro of selected sodium phosphates (under the corporate names Hexa 68, Hexa 70, Trikrystal, FST, Pyro 52, KPS, Didi on selected gram-positive and gram-negative bacteria. Seven different concentrations of each phosphate were used. Sensitivity of the bacterial strains to phosphates was observed in broth supplemented with salts. In vitro was showed a negative effect of various phosphates on growth of selected gram-positive bacteria. Orthophosphates and diphosphates (pyrophosphates did not have significant inhibitory effect on tested bacteria at neutral pH. With the exception of phosphate Trikrystal has not been found in vitro significant inhibitory effects on gram-negative bacteria.doi:10.5219/141

Vanadate influence on metabolism of sugar phosphates in fungus Phycomyces blakesleeanus.

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Milan Žižić

Full Text Available The biological and chemical basis of vanadium action in fungi is relatively poorly understood. In the present study, we investigate the influence of vanadate (V5+ on phosphate metabolism of Phycomyces blakesleeanus. Addition of V5+ caused increase of sugar phosphates signal intensities in 31P NMR spectra in vivo. HPLC analysis of mycelial phosphate extracts demonstrated increased concentrations of glucose 6 phosphate, fructose 6 phosphate, fructose 1, 6 phosphate and glucose 1 phosphate after V5+ treatment. Influence of V5+ on the levels of fructose 2, 6 phosphate, glucosamine 6 phosphate and glucose 1, 6 phosphate (HPLC, and polyphosphates, UDPG and ATP (31P NMR was also established. Increase of sugar phosphates content was not observed after addition of vanadyl (V4+, indicating that only vanadate influences its metabolism. Obtained results from in vivo experiments indicate catalytic/inhibitory vanadate action on enzymes involved in reactions of glycolysis and glycogenesis i.e., phosphoglucomutase, phosphofructokinase and glycogen phosphorylase in filamentous fungi.

Uptake of CrO42- ions by Fe-treated tri-calcium phosphate

International Nuclear Information System (INIS)

Serrano G, J.; Ramirez S, J. L.; Bonifacio M, J.; Granados C, F.; Badillo A, V. E.

2010-01-01

CrO 4 2- ion adsorption of Fe-treated tri-calcium phosphate was studied by batch experiments as a function of contact time, initial concentration of metal ion and temperature. Adsorption results showed that at ph 5.5 and 1.0 x 10 -4 M chromium concentration the adsorption capacity of Fe-treated tri-calcium phosphate for CrO 4 2- ions was 7.10 x 10 -3 mmol/g. Chromium adsorption data on Fe-treated tri-calcium phosphate at various initial concentration fitted the Freundlich isotherm. By temperature studies the thermodynamic parameters ΔH 0 , ΔG 0 and ΔS 0 were estimated and the obtained results showed that the adsorption reaction was endothermic and spontaneous. (Author)

A novel electrochemical aptamer-antibody sandwich assay for lysozyme detection.

Science.gov (United States)

Ocaña, Cristina; Hayat, Akhtar; Mishra, Rupesh; Vasilescu, Alina; del Valle, Manel; Marty, Jean-Louis

2015-06-21

In this paper, we have reported a novel electrochemical aptamer-antibody based sandwich biosensor for the detection of lysozyme. In the sensing strategy, an anti-lysozyme aptamer was immobilized onto the carbon electrode surface by covalent binding via diazonium salt chemistry. After incubating with a target protein (lysozyme), a biotinylated antibody was used to complete the sandwich format. The subsequent additions of avidin-alkaline phosphatase as an enzyme label, and a 1-naphthyl phosphate substrate (1-NPP) allowed us to determine the concentration of lysozyme (Lys) via Differential Pulse Voltammetry (DPV) of the generated enzyme reaction product, 1-naphthol. Using this strategy, a wide detection range from 5 fM to 5 nM was obtained for a target lysozyme, with a detection limit of 4.3 fM. The control experiments were carried out by using bovine serum albumin (BSA), cytochrome c and casein. The results showed that the proposed biosensor had good specificity, stability and reproducibility for lysozyme analysis. In addition, the biosensor was applied for detecting lysozyme in spiked wine samples, and very good recovery rates were obtained in the range from 95.2 to 102.0% for lysozyme detection. This implies that the proposed sandwich biosensor is a promising analytical tool for the analysis of lysozyme in real samples.

Effect of fertilizer type on cadmium and fluorine concentrations in clover herbage

International Nuclear Information System (INIS)

McLaughlin, M.J.

2002-01-01

This study investigated whether changing phosphatic fertilizer type affects the accumulation of cadmium (Cd) and fluorine (F) in pasture herbage. North Carolina phosphate rock and partially acidulated fertilizers derived from this rock generally have higher Cd and F concentrations compared to single superphosphate currently manufactured in Australia. Clover herbage from sites of the National Reactive Phosphate Rock (RPR) trial was collected and analysed for concentrations of Cd (11 sites) and F (4 sites). A comparison was made between pastures fertilized with 4 rates of single superphosphate, North Carolina phosphate rock, and partially acidulated phosphate rock having Cd concentrations of 283, 481, and 420 mg Cd/kg P respectively, and 170, 271, and 274 g F/kg P respectively. One site used Hemrawein (Egypt) phosphate rock (HRP) having a Cd and F concentration of 78 mg Cd/kg P and 256 g F/kg P respectively. To help identify differences in herbage Cd concentrations between sites, unfertilised soils from each site were analyzed for total and extractable Cd contents. At one site Cd concentrations in bulk herbage (clover, grasses and weeds) were related to infestation of the pasture by capeweed (Arctotheca calendula L. Levyns). There were no significant differences between F in herbage from plots fertilized with single superphosphate, partially acidulated phosphate rock or North Carolina phosphate rock, or between sites. Concentrations of F in herbage were low, generally less than 10 mg F /kg. However, there were large differences in Cd concentrations in herbage between sites, while differences between fertilizer treatments were small in comparison. The site differences were only weakly related to total or extractable (0.01 mol/L CaCl 2 ) Cd concentrations in soil. Significant differences in Cd concentrations in clover due to fertilizer type were found at 5 sites. North Carolina phosphate rock treatments had significantly higher Cd concentrations in clover compared to

The Impact of Phosphate Loading Activities on Environment: The Egyptian Red Sea Coast

International Nuclear Information System (INIS)

El-Shabasy, A.M.; Diab, H.M.; Ataiw, S.E.H.

2013-01-01

The phosphate industry in Egypt includes three major activities, namely, mining and milling of phosphate rock, phosphate product manufacture, and phosphate product use. The production of fertilizers from natural phosphate ore can lead to the redistribution of uranium and other radionuclides in products, by-products and residues and hence, to severe environmental impacts and increased radiation exposures. In this study, the impact of loading cargoes of phosphate ore into ships at the Red Sea coast has been evaluated. The main objective was to assess the impact of phosphate loading activities near marine environment by determining the activity concentrations of '2 26 Ra ( 238 U) series, 232 Th series and 40 K in soil, sediment and seawater from El- Hamraween and Safaga Port where phosphate mine. The specific activities of 226 Ra ( 238 U) series, 232 Th series and 40 K (Bq/kg dry weight) were measured using gamma ray spectrometers based on hyper-pure germanium detectors. The specific activities showed high concentration level of 226 Ra. The concentration and distribution pattern of 226 Ra in sediment can be used to trace the radiological impact of the non-nuclear industries on the Red Sea coast. The absorbed dose (nGy/h) was also evaluated and can be used as a pre-operational baseline to estimate the possible radiological impacts due to mining, processing and future phosphate industrial activities. Because of the limited measures to control radiological hazards to individuals and the environment, normal occupational health and environmental protection measures were designed to protect against radiological hazards.

Role of magnesium on the biomimetic deposition of calcium phosphate

Science.gov (United States)

Sarma, Bimal K.; Sarma, Bikash

2016-10-01

Biomimetic depositions of calcium phosphate (CaP) are carried out using simulated body fluid (SBF), calcifying solution and newly developed magnesium containing calcifying solution. Calcium phosphate has a rich phase diagram and is well known for its excellent biocompatibility and bioactivity. The most common phase is hydroxyapatite (HAp), an integral component of human bone and tooth, widely used in orthopedic and dental applications. In addition, calcium phosphate nanoparticles show promise for the targeted drug delivery. The doping of calcium phosphate by magnesium, zinc, strontium etc. can change the protein uptake by CaP nanocrystals. This work describes the role of magnesium on the nucleation and growth of CaP on Ti and its oxide substrates. X-ray diffraction studies confirm formation of HAp nanocrystals which closely resemble the structure of bone apatite when grown using SBF and calcifying solution. It has been observed that magnesium plays crucial role in the nucleation and growth of calcium phosphate. A low magnesium level enhances the crystallinity of HAp while higher magnesium content leads to the formation of amorphous calcium phosphate (ACP) phase. Interestingly, the deposition of ACP phase is rapid when magnesium ion concentration in the solution is 40% of calcium plus magnesium ions concentration. Moreover, high magnesium content alters the morphology of CaP films.

Pretreatment of Raw Biochar and Phosphate Removal Performance of Modified Granular Iron/Biochar

Institute of Scientific and Technical Information of China (English)

Jing Ren; Nan Li; Lin Zhao; Lei Li

2017-01-01

Biochar is a potential carrier for nutrients due to its porous nature and abundant functional groups. However, raw biochar has a limited or even negative capacity to adsorb phosphate. To enhance phosphate removal and reduce phos-phate releases, acidic, alkaline, and surfactant pretreatments, followed by granulation and ferric oxide loading, were applied to raw biochar powder (Bp). The alkaline pretreatment proved to be the most effective method and exhibited significant pore expansion and surface oxidation. Bg-OH-FO showed the highest phosphate removal efficiency at 99.2%(initial phos-phate concentration of 20 mg/L) after granulation and ferric oxide loading. Static adsorption results indicated that a pH value of 4 was the most suitable for phosphate adsorption because of the surface properties of Bg-OH-FO and the dis-tribution of P (V) in water. Higher temperatures and a larger initial phosphate concentration led to better adsorption;the adsorption capacity of Bg-OH-FO was 1.91 mg/g at 313 K with an initial phosphate concentration of 50 mg/L. The Bg-OH-FO adsorption process was endothermic in nature. The Freundlich model seemed to be the optimum isotherm model for Bg-OH-FO. Under continuous adsorption, the flow rate and bed depth were changed to optimize the operation con-ditions. The results indicate that a slow flow rate and high bed depth helped increase the removal efficiency (η) of the fixed bed. The breakthrough curves fitted well with the Yoon–Nelson model.

Preparation and Characterization of Apatitic Biphasic Calcium Phosphate

International Nuclear Information System (INIS)

Thin Thin Nwe; Kyaw Naing; Khin Mar Tun; Nyunt Wynn

2005-09-01

The apatitic biphasic calcium phosphate (ABcp) consisting of hydroxyapatite (HA) and -tricalcium phosphate ( -Tcp) has been prepared by precipitation technique using slaked lime and orthophosphoric acid. The X-ray diffraction analysis of the product I (hydroxyapatite) revealed that ABcp was partially crystalline state. However, on heating at 800 C for 8 hrs, XRD pattern indicated a perfectly crystalline form of ABcp. This observation was supported by FT-IR measurement. The change in morphology regarding in the functional nature was infered by the shift in the FT-IR frequency. The optimization of the apatitic biphasic calcium phosphate was done by the variation of disodium hydrogen phosphate concentration, setting time, hardening time as well as compressive strength. The perpared cement may be used as an artificial substitution bone

Cyclic-2,3-diphosphoglycerate levels in Methanobacterium thermoautotrophicum reflect inorganic phosphate availability.

Science.gov (United States)

Seely, R J; Krueger, R D; Fahrney, D E

1983-11-15

Methanobacterium thermoautotrophicum was grown in phosphate-limited chemostat cultures at a dilution rate corresponding to a doubling time of 13.2 h. The cyclic-2,3-diphospho-D-glycerate content of these cells was 8 to 10-fold lower than that of cells grown in batch cultures having a doubling time of 11.5 h. This metabolite accounted for 5% of cell dry weight during batch growth on 2 mM phosphate. In the chemostat the steady-state concentration of phosphate was 4 microM, showing that this methanogen is adapted to highly efficient growth at low phosphate concentrations. Since growth rates were similar in both cultures, the growth rate clearly does not depend on intracellular levels of cyclic-2,3-diphosphoglycerate.

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.

Optimization of Liquid Medium for High Phosphate Solubilization by Serratia Marcescens Strain AGKT4

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Mohd Yusoff Abd. Samad

2017-12-01

Full Text Available This study is on the optimization of the medium for solubilization of phosphate based on the Box-Behnken design and response surface methodology. Optimization of the liquid medium for phosphate solubilization using Serratia marcescens strain AGKT4 was carried out by varying the concentrations of 3 ingredients; the fructose, peptone and inoculum size of bacteria. A mathematical model derived from the response surface methodology was then validated statistically for the target test variables. The highest phosphate solubilization in the medium was achieved at the optimal concentrations of fructose and peptone at 6% (w/v and 0.6% (w/v, respectively. The maximum phosphate solubilization at these concentrations was 239.12 µg/mL. Under the same conditions, the bacterial growth in the medium was 9 log10 CFU.

Phosphatization Associated Features of Ferromanganese Crusts at Lemkein Seamount, Marshall Islands

Science.gov (United States)

Choi, J.; Lee, I.; Park, B. K.; Kim, J.

2014-12-01

Old layers of ferromanganese crusts, especially in the Pacific Ocean, have been affected by phosphatization. Ferromanganese crusts on Lemkein seamount in Marshall Islands also are phosphatized (3.3 to 4.2 wt % of P concentration). Furthermore, they have characteristic features that are different from other ferromanganese crusts. These features occur near the phosphorite, which were thought to fill the pore spaces of ferromanganese crusts. Inside the features, ferromanganese crusts are botryoidally precipitated from the round-boundary. The features of the phosphatized lower crusts of Lemkein seamount are observed using microscope and SEM. Elemental compositions of the selected samples were analyzed by SEM-EDS. Based on the observation and analysis of samples, three characteristic structures are identified: (1) phosphate-filled circles, (2) tongue-shaped framboidal crust, and (3) massive framboidal crust. The phosphate-filled circles are mostly composed of phosphorite, and they include trace fossils such as foraminifera. Phosphatized ferromanganese crusts exist at the boundary of this structure. The tongue-shaped crust is connected with the lips downward, and ferromanganese crusts inside the tongue show distinct growth rim. The massive framboidal crust is located below the tongue. Ferromanganese crusts in the massive framboidal crust are enveloped by phosphate, and some of the crusts are phosphatized. Around the structures, Mn oxide phase is concentrated as a shape of corona on BSE image. All of the structures are in the phosphatized crusts that show columnar growth of ferromanganese crusts and have sub-parallel lamination. These observation and chemical analysis of the ferromanganese crusts can provide a clue of diagenetic processes during the formation of ferromanganese crusts.

The influence of Sr content in calcium phosphate coatings

International Nuclear Information System (INIS)

Lindahl, Carl; Pujari-Palmer, Shiuli; Hoess, Andreas; Ott, Marjam; Engqvist, Håkan; Xia, Wei

2015-01-01

In this study calcium phosphate coatings with different amounts of strontium (Sr) were prepared using a biomineralization method. The incorporation of Sr changed the composition and morphology of coatings from plate-like to sphere-like morphology. Dissolution testing indicated that the solubility of the coatings increased with increased Sr concentration. Evaluation of extracts (with Sr concentrations ranging from 0 to 2.37 μg/mL) from the HA, 0.06Sr, 0.6Sr, and 1.2Sr coatings during in vitro cell cultures showed that Sr incorporation into coatings significantly enhanced the ALP activity in comparison to cells treated with control and HA eluted media. These findings show that calcium phosphate coatings could promote osteogenic differentiation even in a low amount of strontium. - Highlights: • Calcium phosphate coating doping with low Sr contents was prepared via a biomineralization process. • The solubility of the coatings increased with increased Sr concentration. • Present findings show the potential that Sr has on promoting osteogenic differentiation even in a low amount

Bulk solubility and speciation of plutonium(VI) in phosphate-containing solutions

International Nuclear Information System (INIS)

Weger, H.T.; Okajima, S.; Cunnane, J.C.; Reed, D.T.

1992-01-01

The solubility and speciation of Pu(VI) with phosphate as a function of pH was investigated to determine the ability of phosphate to act as an actinide getter. The general properties were first investigated and are reported here with the goal of performing more quantitative experiments in the future. Solubility was approached from oversaturation at initial pH = 4, 10 and 13.4. Absorption spectra were recorded, the solution filtered and the filtrate counted. Absorption spectra were obtained at varying phosphate concentrations and at pH of 2.7 to 11.9. The effect of complexation on the 833 mn Pu(VI) band was characterized. Evidence for three phosphate complexes was obtained for pH -5 to 10 -6 M Pu(VI) was measured in the filtrate at pH ≤ 10 that were passed through a 50 mn filter. Pu(VI) complexes with phosphate over hydroxide at pH ≤ 11.6, but at pH ≥ 11.9, only hydrolyzed Pu(VI) was detected. At pH = 12, the concentration of Pu(VI) was as high as 10 -4 M

Radionuclide fluxes at a plant manufacturing dicalcium phosphate for domestic animals

International Nuclear Information System (INIS)

Gaefvert, T.; Holm, E.

2002-01-01

The objectives of this study is to map out the fluxes of radionuclides from the 238 U decay series as well as estimate doses to workers at a dicalcium phosphate plant. At the studied plant phosphate rock is used for the production of dicalcium phosphate, which is a source of calcium and phosphorous for domestic animals. A by-product in the manufacturing process is calcium chloride which is used in the oil industry, food industry and as road salt. In the phosphate rock, the radionuclides were found in secular radioactive equilibrium with an average activity concentration of 830 Bq·kg -1 . Separation and concentration processes was observed. Most of the 226 Ra was found in the calcium chloride while the major part of 238 U was found in the dicalcium phosphate, about 950 Bq·kg -1 . The annual occupational effective dose to workers was found to be below the 1 mSv limit. The study shows a good example of an important non-nuclear industry with a high input of natural radionuclides and several conceivable pathways to man. (author)

Serum-Sphingosine-1-Phosphate Concentrations Are Inversely Associated with Atherosclerotic Diseases in Humans.

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Irina Soltau

Full Text Available Atherosclerotic changes of arteries are the leading cause for deaths in cardiovascular disease and greatly impair patient's quality of life. Sphingosine-1-phosphate (S1P is a signaling sphingolipid that regulates potentially pro-as well as anti-atherogenic processes. Here, we investigate whether serum-S1P concentrations are associated with peripheral artery disease (PAD and carotid stenosis (CS.Serum was sampled from blood donors (controls, N = 174 and from atherosclerotic patients (N = 132 who presented to the hospital with either clinically relevant PAD (N = 102 or CS (N = 30. From all subjects, serum-S1P was measured by mass spectrometry and blood parameters were determined by routine laboratory assays. When compared to controls, atherosclerotic patients before invasive treatment to restore blood flow showed significantly lower serum-S1P levels. This difference cannot be explained by risk factors for atherosclerosis (old age, male gender, hypertension, hypercholesteremia, obesity, diabetes or smoking or comorbidities (Chronic obstructive pulmonary disease, kidney insufficiency or arrhythmia. Receiver operating characteristic curves suggest that S1P has more power to indicate atherosclerosis (PAD and CS than high density lipoprotein-cholesterol (HDL-C. In 35 patients, serum-S1P was measured again between one and six months after treatment. In this group, serum-S1P concentrations rose after treatment independent of whether patients had PAD or CS, or whether they underwent open or endovascular surgery. Post-treatment S1P levels were highly associated to platelet numbers measured pre-treatment.Our study shows that PAD and CS in humans is associated with decreased serum-S1P concentrations and that S1P may possess higher accuracy to indicate these diseases than HDL-C.

Radiological and chemical assessment of phosphate rocks in some countries

International Nuclear Information System (INIS)

Cevik, U.; Baltas, H.; Tabak, A.; Damla, N.

2010-01-01

In this study, the radiological, structural and chemical characterizations of Mardin-Mazidagi phosphate rock, which is an important phosphate fertilizer source in Turkey were investigated and compared to those of several different phosphate rocks of Tunisia, Egypt, Morocco, Algeria and Syria using gamma spectrometry, X-ray diffraction (XRD) and X-ray fluorescence (XRF) measurement techniques. Elemental analysis results of phosphate samples showed that they were mainly composed of CaO, P 2 O 5 , SiO 2 , Al 2 O 3 , SO 3 and Fe 2 O 3 . Elemental concentrations of U and Th were calculated using 226 Ra and 232 Th activity concentrations, respectively. As a result of XRD analysis, the main peaks of the samples were found to be Fluorapatite (Ca 5 (PO 4 ) 3 F). The radioactivity concentration levels for 226 Ra, 232 Th and 40 K in all phosphate samples ranged from 250 to 1029 Bq kg -1 with a mean of 535 Bq kg -1 , from 5 to 50 Bq kg -1 with a mean of 20 Bq kg -1 and from 117 to 186 Bq kg -1 with a mean of 148 Bq kg -1 , respectively. The computed values of annual effective doses ranged from 0.17 to 0.59 mSv, with a mean value of 0.33 mSv, which is lower than the recommended limit of 1 mSv y -1 by the International Commission on Radiological Protection.

Effect of submarine groundwater discharge containing phosphate on coral calcification

Science.gov (United States)

Yasumoto, J.; Yasumoto, K.; Iijima, M.; Nozaki, M.; Asai, K.; Yasumoto, M. H.

2017-12-01

It is well known that the anthropogenic eutrophication enriched with various substances including phosphate in coastal waters has resulted in coral degradation. However, to the best of our knowledge, the phosphate threshold value to inhibit the coral calcification has been unclear, due to the unknown mechanisms involved in the inhibition of the calcification by phosphate. In island regions, groundwater is one of the most important clues to transport the nutrients contained in livestock or agricultural wastewaters. However, the actual conditions of coastal pollution with such nutrients have not been understood because of unperceived submarine groundwater discharge (SGD). In this study, to quantify of extremely rapid and localized SGD from Ryukyu limestone aquifer, we investigated the rate and concentration of phosphate of SGD using automated seepage mater in Yoron Island, which is located southern part of Japan. And, to elucidate the inhibition mechanisms for phosphate against coral calcification, we examined its effect on the bottom skeleton formation in primary polyps of Acropora digitifera by using the fluorescence derivatizing reagent having phosphate group (FITC-AA). As a result, the SGD was found to contain 1 to 2 µM of phosphate as much as the concentration in the coastal ground water under agricultural land. Moreover, the amount of phosphate contained in the surface layers of bottom calcareous sands close to the region of SGD were about 5 µmol/g. When the primary polyps were treated with 50 µM of FITC-AA, the bottom skeleton of the primary polyps showed the fluorescence from FITC-AA within a few minutes, suggesting the phosphate binding. Furthermore, when the polyps were treated with 10 µM of FITC-AA, irregular patterns of the elongated skeleton were observed. These results led us to conclude that phosphate is transported via a paracellular pathway to the subcalicoblastic extracellular calcifying medium. These results indicate that the phosphate adsorbed

Interference of different ionic species on the analysis of phosphate in HLW using spectrophotometer

International Nuclear Information System (INIS)

Mishra, P.K.; Ghongane, D.E.; Valsala, T.P.; Sonavane, M.S.; Kulkarni, Y.; Changrani, R.D.

2010-01-01

During reprocessing of spent nuclear fuel by PUREX process different categories of radioactive liquid wastes like High Level (HL), Intermediate Level (IL) and Low Level (LL) are generated. Different methodologies are adopted for management of these wastes. Since PUREX solvent (30% Tri butyl phosphate-70% Normal Paraffin Hydrocarbon) undergoes chemical degradation in the highly acidic medium of dissolver solution, presence of phosphate in the waste streams is inevitable. Since higher concentrations of phosphate in the HLW streams will affect its management by vitrification, knowledge about the concentration of phosphate in the waste is essential before finalising the glass composition. Since a large number of anionic and cationic species are present in the waste, these species may interfere phosphate analysis using spectrophotometer. In the present work, the interference of different anionic and cationic species on the analysis of phosphate in waste solutions using spectrophotometer was studied

Recovery of uranium from the Syrian phosphate by solid-liquid method using alkaline solutions

International Nuclear Information System (INIS)

Shlewit, H.; Alibrahim, M.

2007-01-01

Uranium concentrations were analyzed in the Syrian phosphate deposits. Mean concentrations were found between 50 and 110 ppm. As a consequence, an average phosphate dressing of 22 kg/ha phosphate would charge the soil with 5-20 g/ha uranium when added as a mineral fertilizer. Fine grinding phosphate produced at the Syrian mines was used for uranium recovery by carbonate leaching. The formation of the soluble uranyl tricarbonate anion UO 2 (CO 3 ) 3 4- permits use of alkali solutions of sodium carbonate and sodium bicarbonate salts for the nearly selective dissolution of uranium from phosphate. Separation of iron, aluminum, titanium, etc., from the uranium during leaching was carried out. Formation of some small amounts of molybdates, vanadates, phosphates, aluminates, and some complexes metal was investigated. This process could be used before the manufacture of TSP fertilizer, and the final products would contain smaller uranium quantities. (author)

Multidisciplinary study of radionuclides and heavy-metal concentrations in wildlife on phosphate-mined and reclaimed lands. Final report

International Nuclear Information System (INIS)

Pritchard, P.C.H.; Bloodwell, J.M.

1986-11-01

The phosphate-rich mineral deposits of central Florida tend to exhibit background radiation levels that are elevated due to the uranium and its decay products found in association with the ore. The report documents radioactivity levels in two groups of animals that had heretofore not been examined by other investigators -- aquatic reptiles (American alligators, softshell turtles, and Florida cooter turtles) and terrestrial mammals (armadillos), based on the criterion that these species have significant proportions of their mass comprised of bony tissue likely to show elevated concentrations of radium. The alligator bones contained only low concentrations of radium, and there were no significant differences between alligators collected from mined, mineralized-unmined, or unmineralized land. Whether the levels of radium in the bones of the turtles represents a hazard to the health of these long-lived animals or to humans who may consume their flesh is unclear

Interfacial Precipitation of Phosphate on Hematite and Goethite

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Lijun Wang

2018-05-01

Full Text Available Adsorption and subsequent precipitation of dissolved phosphates on iron oxides, such as hematite and goethite, is of considerable importance in predicting the bioavailability of phosphates. We used in situ atomic force microscopy (AFM to image the kinetic processes of phosphate-bearing solutions interacting with hematite or goethite surfaces. The nucleation of nanoparticles (1.0–4.0 nm in height of iron phosphate (Fe(III-P phases, possibly an amorphous phase at the initial stages, was observed during the dissolution of both hematite and goethite at the earliest crystallization stages. This was followed by a subsequent aggregation stage where larger particles and layered precipitates are formed under different pH values, ionic strengths, and organic additives. Kinetic analysis of the surface nucleation of Fe-P phases in 50 mM NH4H2PO4 at pH 4.5 showed the nucleation rate was greater on goethite than hematite. Enhanced goethite and hematite dissolution in the presence of 10 mM AlCl3 resulted in a rapid increase in Fe-P nucleation rates. A low concentration of citrate promoted the nucleation, whereas nucleation was inhibited at higher concentrations of citrate. By modeling using PHREEQC, calculated saturation indices (SI showed that the three Fe(III-P phases of cacoxenite, tinticite, and strengite may be supersaturated in the reacted solutions. Cacoxenite is predicted to be more thermodynamically favorable in all the phosphate solutions if equilibrium is reached with respect to hematite or goethite, although possibly only amorphous precipitates were observed at the earliest stages. These direct observations at the nanoscale may improve our understanding of phosphate immobilization in iron oxide-rich acid soils.

Thermal reduction and U-recovery from uraniferous phosphorite concentrate of phosphatic sandstone deposit of G. Qatrani, western desert, Egypt

International Nuclear Information System (INIS)

Abdel Monem, H.M.

1988-01-01

The produced uraniferous phosphorite concentrate from cationic floatation of phosphatic sandstone of G. Qatrani contain 32.01% P 2 O 5 , 0.39% eU and 5.65% SiO 2 . Thermal reduction technique using a high calorific hydrocarbon (Mazout) is used to recover U and P 2 O 5 . At elevated temperature ranging from 500 to 800 0 C, reducing gases mainly, Co are evolved due to mazout cracking; beside a carbon film is precipitated around the treated phosphate grains. These conditions have proved quite beneficial in reducing U+6 into U+4, as well as creating a sufficiently low redox potential below 350 mV in the subsequent leach solution. The effect of different relevant factors are studied and optimized as 700 C, 30 minutes and 20% (wt/wt) ratio for reducing temperature, duration time and amount of reductant added respectively. Hydrochloric acid of 8 N appears to offer the best potential for acidulation of the reduced phosphates at room temperature (25 0 C) and 30 minutes retention time of agitation leaching. The results showed that, more than 98% of P 2 O 5 reports in solution as phosphoric acid and about 97% of uranium is retained in an insoluble form (U+4). Applying oxidizing roast of the leached reduced materials at 800 0 C in the presence of 2% NaCl, would result in both removing the carbon content and oxidizing the contained U+4 to U+6. By subsequent leaching with dilute acidic solution (2N HCl) more than 98% of the contained U+6 is readily soluble

Effectiveness and cost-efficiency of phosphate binders in hemodialysis

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Zsifkovits, Johannes

2009-06-01

Full Text Available Health political background: In 2006, the prevalence of chronic renal insufficiency in Germany was 91,718, of which 66,508 patients were on dialysis. The tendency is clearly growing. Scientific background: Chronic renal insufficiency results in a disturbance of the mineral balance. It leads to hyperphosphataemia, which is the strongest independent risk factor for mortality in renal patients. Usually, a reduction in the phosphate intake through nutrition and the amount of phosphate filtered out during dialysis are not sufficient to reduce the serum phosphate values to the recommended value. Therefore, phosphate binders are used to bind ingested phosphate in the digestive tract in order to lower the phosphate concentration in the serum. Four different groups of phosphate binders are available: calcium- and aluminium salts are the traditional therapies. Sevelamer and Lanthanum are recent developments on the market. In varying doses, all phosphate binders are able to effectively lower phosphate concentrations. However, drug therapies have achieved recommended phosphate levels in only 50 percent of patients during the last years. Research questions: How effective and efficient are the different phosphate binders in chronic renal insufficient patients? Methods: The systematic literature search yielded 1,251 abstracts. Following a two-part selection process with predefined criteria 18 publications were included in the assessment. Results: All studies evaluated conclude that serum phosphate, serum calcium and intact parathyroid hormone can be controlled effectively with all phosphate binders. Only the number of episodes of hypercalcaemia is higher when using calcium-containing phosphatebinders compared to Sevelamer and Lanthanum. Regarding the mortality rate, the cardiovascular artery calcification and bone metabolism no definite conclusions can be drawn. In any case, the amount of calcification at study start seems to be crucial for the further

Cadmium and zinc in soil solution extracts following the application of phosphate fertilizers.

Science.gov (United States)

Lambert, Raphaël; Grant, Cynthia; Sauvé, Sébastien

2007-06-01

This study investigated the solubility of cadmium and zinc in soils after the application of phosphate fertilizers containing those two metals. The solubility of cadmium and zinc was assessed by measuring their concentration in soil water extracts. Three monoammonium phosphate fertilizers containing various amounts of metals were applied on cultivated fields for 3 years at three different rates. In order to investigate the effects of long-term applications of fertilizers on the solubility of Cd and Zn, a similar design was used to apply contaminated fertilizers to soils in a laboratory experiment using a single fertilizer addition equivalent to 15 years of application. Phosphate fertilizers increased the concentration of Cd in soil extracts compared to control in 87% and 80% of the treatments in field and laboratory experiments respectively. Both increasing the rate of application and using fertilizer containing more Cd lead to higher Cd concentrations in extracts for the field and the laboratory experiments. The addition of the equivalent of 15 years of fertilizer application in the laboratory results in higher Cd concentration in extracts compared to the field experiment. For Zn, the fertilizer treatments enhanced the metal solution concentration in 83% of field treatments, but no significant correlations could be found between Zn inputs and its concentration in solution. In the laboratory, fertilizer additions increase the Zn concentrations in 53% of the treatments and decrease it in most of the other treatments. The decrease in Zn concentrations in the laboratory trial is attributed to the higher phosphate concentrations in the soil solution; which is presumed to have contributed to the precipitation of Zn-phosphates. For both trials, the metal concentrations in soil extracts cannot be related to the Zn concentration in the fertilizer or the rate of application. The high Zn to Cd ratio is presumably responsible for the Cd increase in the soil extracts due to

Aminopropyl-functionalized mesoporous carbon (APTMS-CMK-3) as effective phosphate adsorbent

Science.gov (United States)

Yang, Yanju; Wang, Juanjuan; Qian, Xiaoqing; Shan, Yuhua; Zhang, Haipeng

2018-01-01

Excess phosphate discharge into water bodies can lead to severe eutrophication. Adsorption has been considered as one of the most effective approaches for phosphate removal and recovery. A new aminopropyl-functionalized mesoporous carbon CMK-3 (denoted as APTMS-CMK-3) was prepared and the materials were used as adsorbents for the removal of phosphate in water. The structure, functional groups and surface charge of the materials were characterized by X-ray powder diffraction, transmission electron microscope, N2 adsorption-desorption, elemental analysis, Fourier transform infrared spectra, X-ray photoelectron spectroscopy and zeta potential measurements. The effects of contact time, initial phosphate concentration, solution pH, coexisting anions and dissolved humic acid were studied. The adsorption capacity of APTMS-CMK-3 was 38.09 mg g-1 at the equilibrium concentration of 49.06 mg L-1, and the adsorption data were well fitted with the Freundlich model. As for the reuse of APTMS-CMK-3, a relatively stable adsorption performance was observed after five adsorption-desorption cycles. Therefore, the way of grafting aminopropyl groups on the CMK-3 efficiently enhanced the capability for phosphate adsorption, indicating that it could be used as potential adsorbents for the removal of phosphate in water.

Removal mechanism of phosphate from aqueous solution by fly ash.

Science.gov (United States)

Lu, S G; Bai, S Q; Zhu, L; Shan, H D

2009-01-15

This work studied the effectiveness of fly ash in removing phosphate from aqueous solution and its related removal mechanism. The adsorption and precipitation of phosphate by fly ash were investigated separately in order to evaluate their role in the removal of phosphate. Results showed that the removal of phosphate by fly ash was rapid. The removal percentage of phosphate in the first 5min reached 68-96% of the maximum removal of phosphate by fly ash. The removal processes of phosphate by fly ash included a fast and large removal representing precipitation, then a slower and longer removal due to adsorption. The adsorption of phosphate on fly ash could be described well by Freundlich isotherm equation. The pH and Ca2+ concentration of fly ash suspension were decreased with the addition of phosphate, which suggests that calcium phosphate precipitation is a major mechanism of the phosphate removal. Comparison of the relative contribution of the adsorption and precipitation to the total removal of phosphate by fly ash showed that the adsorption accounted for 30-34% of the total removal of phosphate, depending on the content of CaO in fly ash. XRD patterns of the fly ash before and after phosphate adsorption revealed that phosphate salt (CaHPO4 x 2H2O) was formed in the adsorption process. Therefore, the removal of phosphate by fly ash can be attributed to the formation of phosphate precipitation as a brushite and the adsorption on hydroxylated oxides. The results suggested that the use of fly ash could be a promising solution to the removal of phosphate in the wastewater treatment and pollution control.

Phosphate Recovery from Human Waste via the Formation of Hydroxyapatite during Electrochemical Wastewater Treatment.

Science.gov (United States)

Cid, Clément A; Jasper, Justin T; Hoffmann, Michael R

2018-03-05

Electrolysis of toilet wastewater with TiO 2 -coated semiconductor anodes and stainless steel cathodes is a potentially viable onsite sanitation solution in parts of the world without infrastructure for centralized wastewater treatment. In addition to treating toilet wastewater, pilot-scale and bench-scale experiments demonstrated that electrolysis can remove phosphate by cathodic precipitation as hydroxyapatite at no additional energy cost. Phosphate removal could be predicted based on initial phosphate and calcium concentrations, and up to 80% total phosphate removal was achieved. While calcium was critical for phosphate removal, magnesium and bicarbonate had only minor impacts on phosphate removal rates at concentrations typical of toilet wastewater. Optimal conditions for phosphate removal were 3 to 4 h treatment at about 5 mA cm -2 (∼3.4 V), with greater than 20 m 2 m -3 electrode surface area to reactor volume ratios. Pilot-scale systems are currently operated under similar conditions, suggesting that phosphate removal can be viewed as an ancillary benefit of electrochemical wastewater treatment, adding utility to the process without requiring additional energy inputs. Further value may be provided by designing reactors to recover precipitated hydroxyapatite for use as a low solubility phosphorus-rich fertilizer.

Third phase formation in the extraction of Th(NO_3)_4 by Tri-sec-butyl phosphate. A comparison with Tri-n-butyl phosphate

International Nuclear Information System (INIS)

Chandrasekar, Aditi; Suresh, A.; Sivaraman, N.

2017-01-01

Earlier studies carried out in our laboratory indicated that Tri-sec-butyl phosphate (TsBP) is a potential extractant for U/Th separation. Also, the third phase formation tendency of TsBP is lower compared to its isomers, Tri-n-butyl-phosphate (TBP) and Tri-iso-butyl phosphate (TiBP). In this context, the extraction and third phase formation behaviour of 1.1 M solutions of TiBP and TsBP in n-dodecane in the extraction of Th(IV) from 1 M HNO_3 at 303 K over a wide range of Th concentrations were investigated in the present study and the results are compared with the literature data on TBP system. Concentrations of Th(IV) and HNO_3 loaded in the organic phase before third phase formation (biphasic region) as well as in third phase and diluent-rich phase after third phase formation (triphasic region) were measured as a function of equilibrium aqueous phase Th(IV) concentration. The density of loaded organic phase was also measured at various Th(IV) concentrations. The extraction profiles in the biphasic region indicated that extraction of Th(IV) by TBP is higher than that of TiBP which in turn is higher than that of TsBP. Extractant concentration in the diluent-rich phase and third phase was measured for the triphasic region.

Analytical characterization of ch14.18: a mouse-human chimeric disialoganglioside-specific therapeutic antibody.

Science.gov (United States)

Soman, Gopalan; Kallarakal, Abraham T; Michiel, Dennis; Yang, Xiaoyi; Saptharish, Nirmala; Jiang, Hengguang; Giardina, Steve; Gilly, John; Mitra, George

2012-01-01

Ch14.18 is a mouse-human chimeric monoclonal antibody to the disialoganglioside (GD2) glycolipid. In the clinic, this antibody has been shown to be effective in the treatment of children with high-risk neuroblastoma, either alone or in combination therapy. Extensive product characterization is a prerequisite to addressing the potential issues of product variability associated with process changes and manufacturing scale-up. Charge heterogeneity, glycosylation profile, molecular state and aggregation, interaction (affinity) with Fcγ receptors and functional or biological activities are a few of the critical characterization assays for assessing product comparability for this antibody. In this article, we describe the in-house development and qualification of imaged capillary isoelectric focusing to assess charge heterogeneity, analytical size exclusion chromatography with online static and dynamic light scattering (DLS), batch mode DLS for aggregate detection, biosensor (surface plasmon resonance)-based Fcγ receptor antibody interaction kinetics, N-glycoprofiling with PNGase F digestion, 2-aminobenzoic acid labeling and high performance liquid chromatography and N-glycan analysis using capillary electrophoresis. In addition, we studied selected biological activity assays, such as complement-dependent cytotoxicity. The consistency and reproducibility of the assays are established by comparing the intra-day and inter-day assay results. Applications of the methodologies to address stability or changes in product characteristics are also reported. The study results reveal that the ch14.18 clinical product formulated in phosphate-buffered saline at a concentration of 5 mg/ml and stored at 2-8°C is stable for more than five years.

RBS and XPS analyses of the composite calcium phosphate coatings for biomedical applications

International Nuclear Information System (INIS)

Ide-Ektessabi, Ari; Yamaguchi, Tetsuro; Tanaka, Yoshikazu

2005-01-01

The calcium phosphate coatings on metallic implants are widely used for biomedical applications. The calcium phosphate coatings require mechanical strength, strong adhesion to the metallic implants, chemical stability and low dissolution into the human body fluid for stable functioning in the corrosive environment of the human body. In this study, a novel approach for improving the calcium phosphate coatings is utilized by adding trace metallic element into the coatings. We focused on teeth enamel, which is the hardest calcium phosphate tissue in the human body. Zn concentration increases exponentially from the interior to the surface of the enamel. As the Zn concentration increases, so the local hardness increases. Our previous studies suggest that Zn has influence on the hardness and other properties of enamel, calcium phosphate tissue. Calcium phosphate coatings doped with Zn was fabricated and characterized. The atomic composition and chemical state were investigated by using Rutherford backscattering spectroscopy (RBS) and X-ray photoelectron spectrometer (XPS), respectively. Scratch test was also carried out for measuring the adhesion of the coatings

Characterization of a silver-incorporated calcium phosphate film by RBS and its antimicrobial effects

International Nuclear Information System (INIS)

Han, I-H; Lee, I-S; Song, J-H; Lee, M-H; Park, J-C; Lee, G-H; Sun, X-D; Chung, S-M

2007-01-01

A thin calcium phosphate film was synthesized on both commercially pure Ti and Si wafers by electron beam evaporation of hydroxyapatite as an evaporant with simultaneous Ar ion beam bombardments. Silver was introduced into an ion-beam-assisted deposition of a calcium phosphate thin film for antimicrobial effect. The amount of incorporated silver ions was controlled by immersing calcium-phosphate-coated samples in different AgNO 3 concentrations, and Rutherford backscattering spectrometry (RBS) was employed to measure the amounts of substituted silver. The higher concentration of silver in the calcium phosphate film was more effective in reducing the bacteria of Escherichia coli ATCC 8739 and Streptococcus mutans OMZ 65 on contact with respect to controls

Characterization of a silver-incorporated calcium phosphate film by RBS and its antimicrobial effects

Energy Technology Data Exchange (ETDEWEB)

Han, I-H [Institute of Physics and Applied Physics, and Atomic-Scale Surface Science Research Center, Yonsei University, Seou1 120-749 (Korea, Republic of); Lee, I-S [Institute of Physics and Applied Physics, and Atomic-Scale Surface Science Research Center, Yonsei University, Seou1 120-749 (Korea, Republic of); Song, J-H [Advanced Analysis Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Lee, M-H [Department of Medical Engineering, Yonsei University, Seoul 120-752 (Korea, Republic of); Park, J-C [Department of Medical Engineering, Yonsei University, Seoul 120-752 (Korea, Republic of); Lee, G-H [Korea Institute of Machinery and Materials, Chang-Won 641-010 (Korea, Republic of); Sun, X-D [Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Chung, S-M [Implantium Research Center, Seoul 135-879 (Korea, Republic of)

2007-09-15

A thin calcium phosphate film was synthesized on both commercially pure Ti and Si wafers by electron beam evaporation of hydroxyapatite as an evaporant with simultaneous Ar ion beam bombardments. Silver was introduced into an ion-beam-assisted deposition of a calcium phosphate thin film for antimicrobial effect. The amount of incorporated silver ions was controlled by immersing calcium-phosphate-coated samples in different AgNO{sub 3} concentrations, and Rutherford backscattering spectrometry (RBS) was employed to measure the amounts of substituted silver. The higher concentration of silver in the calcium phosphate film was more effective in reducing the bacteria of Escherichia coli ATCC 8739 and Streptococcus mutans OMZ 65 on contact with respect to controls.

Multivariate statistical analysis of radioactive variables in two phosphate ores from Sudan

International Nuclear Information System (INIS)

Adam, Abdel Majid A.; Eltayeb, Mohamed Ahmed H.

2012-01-01

Multivariate statistical techniques are efficient ways to display complex relationships among many objects. An attempt was made to study the radioactive data in two types of Sudanese phosphate deposits; Kurun and Uro phosphate, using several multivariate statistical methods. Pearson correlation coefficient revealed that a U-238 distribution in Kurun phosphate is controlled by the variation of K-40 concentration, whereas in Uro phosphate it is controlled by the variation of U-235 and U-234 concentration. Histograms and normal Q–Q plots clearly show that the radioactive variables did not follow a normal distribution. This non-normality feature observed may be attributed to complicating influence of geological factors. The principal components analysis (PCA) gives a model of five components for representing the acquired data from Kurun phosphate, where 89.5% of the total variance is explained. A model of four components was sufficient to represent the acquired data from Uro phosphate, where 87.5% of the total data variance is explained. The hierarchical cluster analysis (HCA) indicates that U-238 behaves in the same manner in the two types of phosphates; it associated with a group of four radionuclides; U-234, Po-210, Ra-226, Th-230, which the most abundant radionuclides, and all belong to the uranium-238 decay series. Two parameters have been adapted for the direct differentiate between the two phosphates. Firstly, U-238 in Uro phosphate have shown higher degree of mobility (CV% = 82.6) than that in Kurun phosphate (CV% = 64.7), and secondly, the activity ratio of Th-230/Th-232 in Uro phosphate is nine times than that in Kurun phosphate. - Highlights: ► Multivariate statistical techniques were used to characterize radioactive data. ► U-238 in Uro phosphate shows higher degree of mobility (CV% = 82.6). ► U-238 in Kurun phosphate shows lower degree of mobility (CV% = 64.7). ► The radioactive variables did not follow a normal distribution. ► The ratio of Th

Elevated Concentrations of Serum Immunoglobulin Free Light Chains in Systemic Lupus Erythematosus Patients in Relation to Disease Activity, Inflammatory Status, B Cell Activity and Epstein-Barr Virus Antibodies.

Directory of Open Access Journals (Sweden)

Anette H Draborg

Full Text Available In this study, we examined the concentration of serum immunoglobulin free light chains (FLCs in systemic lupus erythematosus (SLE patients and investigated its association with various disease parameters in order to evaluate the role of FLCs as a potential biomarker in SLE. Furthermore, FLCs' association with Epstein-Barr virus (EBV antibodies was examined.Using a nephelometric assay, κFLC and λFLC concentrations were quantified in sera from 45 SLE patients and 40 healthy controls. SLE patients with renal insufficiency were excluded in order to preclude high concentrations of serum FLCs due to decreased clearance.Serum FLC concentrations were significantly elevated in SLE patients compared to healthy controls (p<0.0001 also after adjusting for Ig levels (p<0.0001. The concentration of serum FLCs correlated with a global disease activity (SLE disease activity index (SLEDAI score of the SLE patients (r = 0.399, p = 0.007. Furthermore, concentrations of FLCs correlated with titers of dsDNA antibodies (r = 0.383, p = 0.009, and FLC levels and SLEDAI scores correlated in the anti-dsDNA-positive SLE patients, but not in anti-dsDNA-negative SLE patients. Total immunoglobulin (IgG and IgA concentrations correlated with FLC concentrations and elevated FLC levels were additionally shown to associate with the inflammatory marker C-reactive protein and also with complement consumption determined by low C4 in SLE patients. Collectively, results indicated that elevated serum FLCs reflects increased B cell activity in relation to inflammation. SLE patients had an increased seropositivity of EBV-directed antibodies that did not associate with elevated FLC concentrations. An explanation for this could be that serum FLC concentrations reflect the current EBV activity (reactivation whereas EBV-directed antibodies reflect the extent of previous infection/reactivations.SLE patients have elevated concentrations of serum FLCs that correlate with global disease

Radioactivity distribution in phosphate products, by-products, effluents, and wastes

International Nuclear Information System (INIS)

Guimond, R.J.; Windham, S.T.

1975-08-01

Phosphate rock throughout the world contains uranium in concentrations ranging from a few ppM to a few hundred ppM. In the United States, phosphate rock normally contains between 100 to 150 ppM uranium. Mining and processing of these ores redistributes much of the uranium daughters among the various products, by-products, and wastes. These materials are then widely dispersed throughout the environment. This redistribution may lead to increased exposure of the public to these naturally-occurring radionuclides. In determining the magnitude of the population exposure caused by this redistribution and in developing environmental standards and controls to prevent contamination of the biosphere from these naturally-occurring radionuclides it is necessary to determine the concentrations and total quantities of these radionuclides in the products, by-products, effluents and wastes of phosphate mining and manufacturing. Samples of phosphate ores, products, by-products, effluents, and wastes were obtained and analyzed for their radioactivity content. Quantities of radioactivity entering the environment through various products, by-products, effluents, and wastes were estimated

Characterisation of Phosphate Accumulating Organisms and Techniques for Polyphosphate Detection: A Review

Directory of Open Access Journals (Sweden)

Cédric Tarayre

2016-05-01

Full Text Available Phosphate minerals have long been used for the production of phosphorus-based chemicals used in many economic sectors. However, these resources are not renewable and the natural phosphate stocks are decreasing. In this context, the research of new phosphate sources has become necessary. Many types of wastes contain non-negligible phosphate concentrations, such as wastewater. In wastewater treatment plants, phosphorus is eliminated by physicochemical and/or biological techniques. In this latter case, a specific microbiota, phosphate accumulating organisms (PAOs, accumulates phosphate as polyphosphate. This molecule can be considered as an alternative phosphate source, and is directly extracted from wastewater generated by human activities. This review focuses on the techniques which can be applied to enrich and try to isolate these PAOs, and to detect the presence of polyphosphate in microbial cells.

Radioimmunoassay of class-specific antibodies (RIACA): chicken antibodies to DNP

International Nuclear Information System (INIS)

Viljanen, M.K.; Granfors, K.; Toivanen, P.

1977-01-01

A radioimmunological method for the quantitation of class-specific antibodies has been developed. The method allows the quantitation of nanogram per ml concentrations of IgG and IgM-anti-DNP antibodies without any physical or chemical pretreatment of the sample. DNP was coupled covalently to a cyanogen bromide activated paper disk with the augmentation of lysine molecule. Anti-DNP antibodies were allowed to react with the coupled DNP and then quantitated by their capacity to bind 125 I-labelled anti-chicken-μ or anti-chicken-γ. The inter-assay variation coefficients ranged from 8.1 to 14.7% and the mean standard deviations of duplicate determinations were about 11%. The combination of this method with the exact immunoradiometric quantitation of the total serum IgM and IgG, and with an immunoabsorption technique, makes it possible to quantitate class-specific antibodies on weight units

Inhibition of calcium phosphate precipitation under environmentally-relevant conditions

International Nuclear Information System (INIS)

Cao Xinde; Harris, Willie G.; Josan, Manohardeep S.; Nair, Vimala D.

2007-01-01

Precipitation of Ca phosphates plays an important role in controlling P activity and availability in environmental systems. The purpose of this study was to determine inhibitory effects on Ca phosphate precipitation by Mg 2+ , SO 4 2- , CO 3 2- , humic acid, oxalic acid, biogenic Si, and Si-rich soil clay commonly found in soils, sediments, and waste streams. Precipitation rates were determined by measuring decrease of P concentration in solutions during the first 60 min; and precipitated solid phases identified using X-ray diffraction and electron microscopy. Poorly-crystalline hydroxyapatite (HAP: Ca 5 (PO 4 ) 3 OH) formed in control solutions over the experiment period of 24 h, following a second-order dependence on P concentration. Humic acid and Mg 2+ significantly inhibited formation of HAP, allowing formation of a more soluble amorphous Ca phosphate phase (ACP), and thus reducing the precipitation rate constants by 94-96%. Inhibition caused by Mg 2+ results from its incorporation into Ca phosphate precipitates, preventing formation of a well-crystalline phase. Humic acid likely suppressed Ca phosphate precipitation by adsorbing onto the newly-formed nuclei. Presence of oxalic acid resulted in almost complete inhibition of HAP precipitation due to preemptive Ca-oxalate formation. Carbonate substituted for phosphate, decreasing the crystallinity of HAP and thus reducing precipitation rate constant by 44%. Sulfate and Si-rich solids had less impact on formation of HAP; while they reduced precipitation in the early stage, they did not differ from the control after 24 h. Results indicate that components (e.g., Mg 2+ , humic acid) producing relatively soluble ACP are more likely to reduce P stability and precipitation rate of Ca phosphate in soils and sediments than are components (e.g., SO 4 2- , Si) that have less effect on the crystallinity

Influence of temperature and ion concentration on sedimentation ...

African Journals Online (AJOL)

TSP sedimentation order also ranged between 0.58 and 1.31 at constant phosphate ions concentration and between 1.55 and 1.81 at constant strontium ions concentration. ... Data may be employed as additional design information for modeling physiochemical phosphate removal in water treatment technology. Keywords: ...

Concentration dependent spectroscopic properties of Dy3+ ions doped boro-phosphate glasses

Science.gov (United States)

Mariyappan, M.; Marimuthu, K.

2016-05-01

Dy3+ ions doped boro-phosphate glasses have been synthesized by melt quenching method and characterized through FTIR, absorption and luminescence spectral measurements. The presence of various stretching and bending vibrations of different borate and phosphate groups were identified from the FTIR spectra. In order to examine the electronic band structure of the studied glasses, Optical energy gap (Eopt) and Urbach energy (ΔE) values were estimated from the absorption spectra. The Judd-Ofelt (JO) intensity parameters were calculated to examine the symmetry of the ligand environment around the Dy3+ ions site. The emission spectra exhibit two intense emission bands at around 482 nm (blue) and 574 nm (yellow) corresponding to the 4F9/2→6H15/2 and 4F9/2→6H13/2 transitions respectively. The emission spectra were characterized through Commission International d'Eclairage (CIE) 1931 chromaticity diagram to explore its suitability for WLED applications.

Staphylococcal enterotoxin-specific IgE antibodies in atopic dermatitis.

Science.gov (United States)

Ide, Fumihito; Matsubara, Tomoyo; Kaneko, Miho; Ichiyama, Takashi; Mukouyama, Tokuko; Furukawa, Susumu

2004-06-01

The authors clarified the clinical significance of the measurement of serum concentrations of specific IgE antibodies to staphylococcal enterotoxin (SE) A- and SEB in atopic dermatitis (AD). The serum concentrations of SEA- and SEB-specific IgE antibodies in 140 pediatric patients with AD were measured with an immuno CAP -radioallergosorbent test system (RAST). To check the cross-reaction of specific IgE antibodies to SEA/SEB and other allergens, the CAP RAST fluorescent enzyme immunoassay inhibition test was performed. Forty-seven patients (33.6%) tested positive for either SEA- or SEB-specific IgE antibodies. School children showed higher positive rates of SEA/SEB-specific IgE antibodies than infants or young children. The patients with severe AD and those with exacerbation of symptoms in summer, had higher positive rates of SEA/SEB-specific IgE antibodies than patients with mild AD or those with exacerbation in winter. In addition, the positive rates of specific IgE antibodies to both dog-dander and cat-dander were higher in patients with positive SEA/SEB-specific IgE antibodies than in patients with negative ones. No cross-reactions occurred among specific IgE antibodies to SEA/SEB and dog/cat dander with one patient's serum, which had positive IgE-specific antibodies against cat/dog dander and SEA/SEB. The positive rate of SEA/SEB-specific IgE antibodies in the patients with dogs and/or cats as pets was 48.4%, which was higher than in those with no pets. Atopic dermatitis patients who exhibit high positive rates of SEA/SEB-specific IgE antibodies were found to be school children, severe cases, cases with high serum concentrations of total IgE, cases with exacerbation in summer, and cases with dogs and/or cats as pets. The measurement of serum concentrations of specific IgE antibodies to SEA and SEB, thus has some value for evaluating AD patients.

Advances in process technology for eco-friendly phosphates by separation of radionuclides

Energy Technology Data Exchange (ETDEWEB)

Singh, H; Mukherjee, T K [Uranium and Rare Earths Extraction Division, Bhabha Atomic Research Centre, Mumbai (India)

1994-06-01

Phosphates are used in the industry for fertilizers, industrial chemicals (detergents, water-treatment chemicals) and food-additives. The source of phosphates for the industry is rock-phosphate. Over 90% of phosphate rocks of the world are associated with uranium and its radioactive daughter products. Processing and use of phosphates is accompanied by radiation hazards. The concentration of radionuclides is low, but in view of large number of persons exposed to the hazards, the cumulative societal pollution load is high, and a matter of concern for international organisations. Chemical engineering techniques have been developed for the reduction of societal radiation hazard from the phosphates. In this paper, brief details of the process and developmental efforts in India are described. (author). 4 refs., 1 fig.

Copper tolerance mediated by polyphosphate degradation and low-affinity inorganic phosphate transport system in Escherichia coli.

Science.gov (United States)

Grillo-Puertas, Mariana; Schurig-Briccio, Lici Ariane; Rodríguez-Montelongo, Luisa; Rintoul, María Regina; Rapisarda, Viviana Andrea

2014-03-19

Metal tolerance in bacteria has been related to polyP in a model in which heavy metals stimulate the polymer hydrolysis, forming metal-phosphate complexes that are exported. As previously described in our laboratory, Escherichia coli cells grown in media containing a phosphate concentration >37 mM maintained an unusually high polyphosphate (polyP) level in stationary phase. The aim of the present work was to evaluate the influence of polyP levels as the involvement of low-affinity inorganic phosphate transport (Pit) system in E. coli copper tolerance. PolyP levels were modulated by the media phosphate concentration and/or using mutants in polyP metabolism. Stationary phase wild-type cells grown in high phosphate medium were significantly more tolerant to copper than those grown in sufficient phosphate medium. Copper addition to tolerant cells induced polyP degradation by PPX (an exopolyphosphatase), phosphate efflux and membrane polarization. ppk-ppx- (unable to synthesize/degrade polyP), ppx- (unable to degrade polyP) and Pit system mutants were highly sensitive to metal even in high phosphate media. In exponential phase, CopA and polyP-Pit system would act simultaneously to detoxify the metal or one could be sufficient to safeguard the absence of the other. Our results support a mechanism for copper detoxification in exponential and stationary phases of E. coli, involving Pit system and degradation of polyP. Data reflect the importance of the environmental phosphate concentration in the regulation of the microbial physiological state.

Immobilization of radioactive strontium in contaminated soils by phosphate treatment

International Nuclear Information System (INIS)

Kim, K.H.; Ammons, J.T.

1990-01-01

The feasibility of in situ phosphate- and metal- (calcium, aluminum, and iron) solution treatment for 90 Sr immobilization was investigated. Batch and column experiments were performed to find optimum conditions for coprecipitation of 90 Sr with Ca-, Al-, and Fe-phosphate compounds in contaminated soils. Separate columns were packed with artificially 85 Sr-contaminated acid soil as well as 90 Sr-contaminated soil from the Oak Ridge Reservation. After metal-phosphate treatment, the columns were then leached successively with either tapwater or 0.001 M CaCl 2 solution. Most of the 85 Sr coprecipitated with the metal phosphate compounds. Immobilization of 85 Sr and 90 Sr was affected by such factors as solution pH, metal and phosphate concentration, metal-to-phosphate ratio, and soil characteristics. Equilibration time after treatments also affected 85 Sr immobilization. Many technology aspects still need to be investigated before field applications are feasible, but these experiments indicate that phosphate-based in situ immobilization should prevent groundwater contamination and will be useful as a treatment technology for 90 Sr-contaminated sites. 15 refs., 3 figs., 1 tab

Antibody-mediated enzyme replacement therapy targeting both lysosomal and cytoplasmic glycogen in Pompe disease.

Science.gov (United States)

Yi, Haiqing; Sun, Tao; Armstrong, Dustin; Borneman, Scott; Yang, Chunyu; Austin, Stephanie; Kishnani, Priya S; Sun, Baodong

2017-05-01

Pompe disease is characterized by accumulation of both lysosomal and cytoplasmic glycogen primarily in skeletal and cardiac muscles. Mannose-6-phosphate receptor-mediated enzyme replacement therapy (ERT) with recombinant human acid α-glucosidase (rhGAA) targets the enzyme to lysosomes and thus is unable to digest cytoplasmic glycogen. Studies have shown that anti-DNA antibody 3E10 penetrates living cells and delivers "cargo" proteins to the cytosol or nucleus via equilibrative nucleoside transporter ENT2. We speculate that 3E10-mediated ERT with GAA will target both lysosomal and cytoplasmic glycogen in Pompe disease. A fusion protein (FabGAA) containing a humanized Fab fragment derived from the murine 3E10 antibody and the 110 kDa human GAA precursor was constructed and produced in CHO cells. Immunostaining with an anti-Fab antibody revealed that the Fab signals did not co-localize with the lysosomal marker LAMP2 in cultured L6 myoblasts or Pompe patient fibroblasts after incubation with FabGAA. Western blot with an anti-GAA antibody showed presence of the 150 kDa full-length FabGAA in the cell lysates, in addition to the 95- and 76 kDa processed forms of GAA that were also seen in the rhGAA-treated cells. Blocking of mannose-6-phosphate receptor with mannose-6-phosphate markedly reduced the 95- and the 76 kDa forms but not the 150 kDa form. In GAA-KO mice, FabGAA achieved similar treatment efficacy as rhGAA at an equal molar dose in reducing tissue glycogen contents. Our data suggest that FabGAA retains the ability of rhGAA to treat lysosomal glycogen accumulation and has the beneficial potential over rhGAA to reduce cytoplasmic glycogen storage in Pompe disease. FabGAA can be delivered to both the cytoplasm and lysosomes in cultured cells. FabGAA equally reduced lysosomal glycogen accumulation as rhGAA in GAA-KO mice. FabGAA has the beneficial potential over rhGAA to clear cytoplasmic glycogen. This study suggests a novel antibody-enzyme fusion protein therapy

Urinary Dialkyl Phosphate Concentrations and Lung Function Parameters in Adolescents and Adults: Results from the Canadian Health Measures Survey.

Science.gov (United States)

Ye, Ming; Beach, Jeremy; Martin, Jonathan W; Senthilselvan, Ambikaipakan

2016-04-01

Epidemiological studies have reported associations between lung function parameters and organophosphate (OP) pesticide exposures in agricultural occupations, but to our knowledge associations have not been evaluated in general populations. We examined associations between OP metabolite dialkyl phosphates (DAPs) and lung function using data from the Canadian Health Measures Survey (CHMS) Cycle 1. Forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), FEV1/FVC ratio, and forced expiratory flow between 25% and 75% of FVC (FEF25%-75%) were measured for 4,446 CHMS participants. Urinary concentrations of six DAP metabolites (DMP, DMTP, DMDTP, DEP, DETP, and DEDTP), smoking status, and other predictors of lung function were also measured in the CHMS-Cycle 1. Multiple linear regression analyses were used to examine the relationship between total DAP concentrations (ΣDAPs) and lung function in adolescents (12-19 years) and adults (20-79 years). In adults, estimates from multiple regression analyses suggested that a 1-unit increase on natural logarithmic scale (171% increase on the original scale) in the creatinine-corrected urinary concentration (nanomoles per gram creatinine) of ΣDAP was associated with a 32.6-mL (95% CI: -57.2, -8.1) reduction in FVC, 32.6-mL (95% CI: -59.0, -6.3) reduction in FEV1, 0.2% (95% CI: -0.6, 0.2) reduction in FEV1/FVC ratio, and 53.1-mL/sec (95% CI: -113.9, 7.7) reduction in FEF25%-75%. In adolescents, associations between ΣDAP and FEV1 were closer to the null and positive for FVC, whereas associations with FEV1/FVC and FEF25%-75% were negative, as in adults. However, none of the associations were significant in adolescents. The negative association between ΣDAP and lung function in adult participants suggests a detrimental effect of OP pesticides on lung function in the adult general population. Further studies using prospective designs are warranted to confirm the findings reported in this study. Ye M, Beach J, Martin JW

Regulation of levels of serum antibodies to ryegrass pollen allergen Lol pIV by an internal image anti-idiotypic monoclonal antibody.

Science.gov (United States)

Zhou, E M; Kisil, F T

1995-03-01

A murine monoclonal anti-idiotypic antibody (anti-Id), designated B1/1, was produced against an idiotope of a murine antibody (mAb91), which recognizes the epitope, site A, of allergen Lol pIV, one of the major groups of allergens in ryegrass (Lolium perenne) pollen. The ability of B1/1 to modulate the antibody responses to Lol pIV was investigated in murine model systems. In the first system, B1/1-keyhole limpet haemocyanin (KLH) conjugate was administered to treat three different strains of mice (C57BL/6, BALB/c and C3H). In the second and third model systems, a solution of B1/1 in phosphate-buffered saline (PBS) was used to treat syngeneic BALB/c mice at various doses and time intervals, respectively. The treatment with either form of B1/1, administered at doses ranging from 100 ng to 100 micrograms mouse, resulted in a reduction of the levels of the antibodies to Lol pIV. In particular, the level of IgE antibodies to Lol pIV was greatly reduced. The administration of a single intravenous (i.v.) injection of a solution of B1/1 8 weeks prior to the challenge with Lol pIV was still effective in reducing the level of antibodies to the allergen. Moreover, the level of antibodies to Lol pIV that expressed the idiotope mAb91 was also markedly decreased. By contrast, it was observed that the level of antibodies to Lol pIV in mice pretreated with B1/1 in PBS at a dose of 10 ng/mouse increased (albeit slightly) compared to that in mice treated with control mAb. These experimental models lend themselves for investigating the mechanism(s) by which an anti-Id modulates antibody responses to a grass pollen allergen.

Refolding Technologies for Antibody Fragments

Directory of Open Access Journals (Sweden)

Tsutomu Arakawa

2014-05-01

Full Text Available Refolding is one of the production technologies for pharmaceutical grade antibody fragments. Detergents and denaturants are primarily used to solubilize the insoluble proteins. The solubilized and denatured proteins are refolded by reducing the concentration of the denaturants or detergents. Several refolding technologies have been used for antibody fragments, comprising dilution, dialysis, solid phase solvent exchange and size exclusion chromatography, as reviewed here. Aggregation suppressor or folding-assisting agents, including arginine hydrochloride, ionic liquids and detergents or denaturants at low concentrations, are included in the refolding solvent to enhance refolding yield.

Kinetics of beta2-microglobulin and phosphate during hemodialysis: effects of treatment frequency and duration.

Science.gov (United States)

Leypoldt, John K

2005-01-01

Current understanding of beta2-microglobulin (beta2M) and phosphate (or inorganic phosphorus) kinetics during hemodialysis is reviewed. The postdialysis:predialysis concentration ratio for beta2M is determined by dialyzer clearance for beta2M, treatment time, patient body size (specifically, extracellular fluid volume), and total ultrafiltration volume during the treatment. Evaluation of these treatment parameters can be used to calculate dialyzer clearance for beta2M; however, such calculated values are only approximations, since they neglect intradialytic generation, nonrenal (nondialyzer) clearance, and postdialysis rebound of beta2M. The detailed kinetics of beta2M during hemodialysis are best described using a two-compartment model. Theoretical predictions from such two-compartment models suggest that the product of dialyzer clearance for beta2M and weekly treatment duration, independent of treatment frequency, is the main determinant of plasma beta2M concentrations. The kinetics of phosphate removal during hemodialysis are incompletely understood. Phosphate is removed from both extracellular and intracellular compartments during hemodialysis; the plasma phosphate concentration levels off after the first 1 or 2 hours of treatment and plasma concentrations can rebound even before therapy is complete. Increases in dialyzer clearance of phosphate have been previously achieved only by increasing dialysis membrane surface area or by the use of hemodiafiltration. A four-compartment model of phosphate kinetics proposed recently by Spalding et al. suggests that the major barrier to phosphate removal is limited transfer of phosphate between the intracellular and extracellular compartments, although other complex factors also play important roles. Theoretical predictions using the model of Spalding et al. suggest that increasing either treatment frequency or treatment duration can increase phosphate removal. The kinetics of beta2M are representative of middle molecules

Mechanism of calcium phosphates precipitation in liquid crystals; Mecanisme de precipitation de phosphates de calcium dans des cristaux liquides

Energy Technology Data Exchange (ETDEWEB)

Prelot, B.; Zemb, T

2004-04-01

The possibility of using as a precursor an easily wet meso-porous powder would be a breakthrough in the preparation of nuclear waste storage ceramics. A concentrated solution containing ions to be stored would wet a dry powder and then, subjected to mild compression, lead to a micro-crystalline matrix of calcium phosphate at acceptable temperatures. Since no porous calcium phosphate different from calcined bone (patented) is described as porous precursor, we have compared the different synthesis routes towards meso-porous ceramics. First, we considered homogeneous precipitation of slats in water: using initially off-stoichiometry in reaction, micron-sized hydroxyapatite particles are produced with a specific surface up to 100 m{sup 2}/g. Then, we consider the classical route of precipitation of an hybrid material in the miscibility gap of a phase diagram, when an hexagonal liquid crystal is used a matrix for precipitation. The surfactant family consists in single chain surfactants containing phosphates as head-group to poison the growing surface of calcium phosphate nano-domains. Since the reaction is still too brutal, we considered using a cat-anionic precursor material of controllable surface charge. For certain concentrations and molar ratios, a new structure not yet described in surfactant precipitation literature is observed: since the periodicity is lower than twice the chain length, a disordered constant curvature monolayer (instead of the classical cylinder of twice chain length diameter) of surfactant is implied. Finally, we have investigated synthesis routes implying slow dissolution of pre-formed calcium phosphate in an already existing hexagonal matrix. For all these routes of synthesis, micro-structural determinations using SAXS, WARS and BET are performed, with a special attention to comparison of the precipitation material, the matrix obtained with all elements present, and also the material obtained after calcinations. (authors)

Effect of phosphate ion on filtration characteristics of solids generated in simulated high level liquid waste

International Nuclear Information System (INIS)

Kondo, Y.

1998-01-01

The effect of phosphate ion on the filtration characteristics of solids generated in a high level liquid waste was experimentally examined. Addition of phosphate ion into the simulated HLLW induced the formation of phosphate such as zirconium phosphate and phosphomolybdic acid. The filtration rate of zirconium phosphate abruptly dropped in the midst of filtration because of a gel-cake formation on the filter surface. The denitration of the simulated HLLW contained zirconium phosphate improved the filterability of this gelatinous solid. The filtration rates of denitrated HLLW decreased with increase of the phosphate ion concentration, since the solids formed by denitration had irregular particle size and configuration in the simulated HLLW with phosphate ion. To increase the filtration rate of denitrated HLLW, a solid suspension filtration tester was designed. The solid-suspension accelerated the filtration rate only in the simulated HLLW with more than 1500 ppm phosphate ion concentration. Under this condition, the simple agitation can easily suspend the constituent solids of filter cake in the solution and a much higher filtration rate can be obtained because the filter cake is continuously swept from the filter surface by rotation of propellers. (authors)

Interstitial and adsorbed phosphates in shelf sediments off Visakhapatnam, east coast of India

Digital Repository Service at National Institute of Oceanography (India)

Sarma; Raju, G.R.K.

Spatial distribution of interstitial and adsorbed phosphates in the shelf sediments shows an increasing trend with distance from coastal to inshore region. Maximum concentration ranges of interstitial and adsorbed phosphates are 16-19 and 40-50 mu g...

The antibody response against human and chimeric anti-TNF therapeutic antibodies primarily targets the TNF binding region

NARCIS (Netherlands)

van Schie, K. A.; Hart, M. H.; de Groot, E. R.; Kruithof, S.; Aarden, L. A.; Wolbink, G. J.; Rispens, T.

2015-01-01

In a subset of patients, anti tumour necrosis factor (TNF) therapeutic antibodies are immunogenic, resulting in the formation of antidrug antibodies (ADAs). Neutralising ADAs compete with TNF for its binding site and reduces the effective serum concentration, causing clinical non-response. It is

Properties and structure of high erbium doped phosphate glass for short optical fibers amplifiers

International Nuclear Information System (INIS)

Seneschal, Karine; Smektala, Frederic; Bureau, Bruno; Floch, Marie Le; Jiang Shibin; Luo, Tao; Lucas, Jacques; Peyghambarian, Nasser

2005-01-01

New phosphate glasses have been developed in order to incorporate high rare-earth ions concentrations. These glasses present a great chemical stability and a high optical quality. The phosphate glass network is open, very flexible, with a linkage of the tetrahedrons very disordered and contains a larger number of non-bridging oxygens (66%). The great stability and resistance against crystallization associated with the possibility to incorporate high doping concentration of rare-earth ions in these phosphate glasses make them very good candidates for the realization of ultra short single mode amplifiers with a high gain at 1.55 μm

Less is More: A Comparison of Antibody-Gold Nanoparticle Conjugates of Different Ratios.

Science.gov (United States)

Byzova, Nadezhda A; Safenkova, Irina V; Slutskaya, Elvira S; Zherdev, Anatoly V; Dzantiev, Boris B

2017-11-15

This comprehensive study is related to gold nanoparticles (GNPs) conjugated with antibodies. The goal of the study is to determine the minimal concentration of antibodies for conjugate synthesis when the conjugates have high antigen-capturing activity. Two systems were studied: gold nanoparticles conjugated with monoclonal antibodies (mAb-GNP) specific to Helicobacter pylori and gold nanoparticles conjugated with polyclonal antibodies (pAb-GNP) specific to mouse immunoglobulins. Several conjugates were synthesized with different GNP-to-antibody molar ratios (from 1:1 to 1:245) through nondirectional and noncovalent immobilization on a surface of GNPs with a diameter of 25.3 ± 4.6 nm. The maximal antigen-capturing activities and equilibrium constants of the conjugates correlate with the formation of a constant hydrodynamic radius of the conjugates for mAb-GNP (GNP to antibody molar ratio 1:58) and with the stabilizing concentration by flocculation curves for pAb-GNP (GNP to antibody molar ratio 1:116). The application of the conjugates to the lateral flow immunoassay shows that the antibody concentrations used for the conjugation can be reduced (below the stabilizing concentration) without losing activity for the mAb-GNP conjugates. The findings highlight that the optimal concentration of antibodies immobilized on the surface of GNPs is not always equal to the stabilizing concentration determined by the flocculation curve.

Hydrocortisone and Vitamin D3 stimulation of 32Psub(i)-phosphate accumulation by organ-cultured chick embryo duodenum

International Nuclear Information System (INIS)

Corradino, R.A.

1979-01-01

Either vitamin D 3 (or 1 α,25-(OH) 2 -D 3 ) or hydrocortisone (HC) stimulated phosphate accumulation by organ-cultured embryonic chick duodenum. In combination, these two steroids stimulated phosphate uptake synergistically. Phosphate accumulation appeared to be independent of other vitamin D 3 -stimulated processes: CaBP concentration, cAMP concentration, or alkaline phosphataseactivity. L-phenylalanine, a reported alkaline phosphate inhibitor, when added to the culture medium progressively inhibited either D 3 - or HC-stimulated phosphate uptake subsequent to culture, but did not inhibit the synergistic action under these conditions L-phenylalanine had no consistent effect on alkaline phosphotase activity but unexpectedly, greatly inhibited vitamin D 3 - stimulated CaBP concentration, but only in the absence of HC. Some limited suggestion of an intestinal phosphoprotein sensitve to either vitamin D 3 or HC was observed. (orig.) [de

Radioimmunoassay method for detection of gonorrhea antibodies

International Nuclear Information System (INIS)

1975-01-01

A novel radioimmunoassay for the detection of gonorrhea antibodies in serum is described. A radionuclide is bound to gonorrhea antigens produced by a growth culture. In the presence of gonorrhea antibodies in the serum, an antigen-antibody conjugate is formed, the concentration of which can be measured with conventional radiometric methods. The radioimmunoassay is highly specific

Calcium concentration in the CAPD dialysate

DEFF Research Database (Denmark)

Bro, S; Brandi, L; Daugaard, H

1998-01-01

OBJECTIVE: To evaluate risk/benefit of various continuous ambulatory peritoneal dialysis (CAPD) dialysate calcium concentrations. DATA SOURCES: A review of the literature on the effects of various CAPD dialysate Ca concentrations on plasma Ca, plasma phosphate, plasma parathyroid hormone (PTH......), doses of calcium carbonate, doses of vitamin D analogs, and requirements of aluminum-containing phosphate binders. STUDY SELECTION: Eleven studies of nonselected CAPD patients, and 13 studies of CAPD patients with hypercalcemia were reviewed. RESULTS: In nonselected CAPD patients, treatment...... with a reduced dialysate Ca concentration (1.00, 1.25, or 1.35 mmol/L) improved the tolerance to calcium carbonate and/or vitamin D metabolites and reduced the need for Al-containing phosphate binders. When using dialysate Ca 1.25 or 1.35 mmol/L, the initial decrease of plasma Ca and increase of PTH could easily...

Third phase formation in the extraction of Th(NO{sub 3}){sub 4} by Tri-sec-butyl phosphate. A comparison with Tri-n-butyl phosphate

Energy Technology Data Exchange (ETDEWEB)

Chandrasekar, Aditi; Suresh, A.; Sivaraman, N. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India). Chemistry Group

2017-06-01

Earlier studies carried out in our laboratory indicated that Tri-sec-butyl phosphate (TsBP) is a potential extractant for U/Th separation. Also, the third phase formation tendency of TsBP is lower compared to its isomers, Tri-n-butyl-phosphate (TBP) and Tri-iso-butyl phosphate (TiBP). In this context, the extraction and third phase formation behaviour of 1.1 M solutions of TiBP and TsBP in n-dodecane in the extraction of Th(IV) from 1 M HNO{sub 3} at 303 K over a wide range of Th concentrations were investigated in the present study and the results are compared with the literature data on TBP system. Concentrations of Th(IV) and HNO{sub 3} loaded in the organic phase before third phase formation (biphasic region) as well as in third phase and diluent-rich phase after third phase formation (triphasic region) were measured as a function of equilibrium aqueous phase Th(IV) concentration. The density of loaded organic phase was also measured at various Th(IV) concentrations. The extraction profiles in the biphasic region indicated that extraction of Th(IV) by TBP is higher than that of TiBP which in turn is higher than that of TsBP. Extractant concentration in the diluent-rich phase and third phase was measured for the triphasic region.

Reaction mechanisms of phosphate with Al(OH)3 and a sandy soil

NARCIS (Netherlands)

Riemsdijk, van W.H.

1979-01-01

Al(OH) ₃ is a very effective sorbent for orthophosphate especially at low pH. At low phosphate concentration c _p , phosphate is adsorbed by an exchange mechanism with singly coordinated OH(H) groups residing on the surface of the Al(OH)

Influence of phosphates when uranium in solutions obtained by attacking Forez with sulfuric acid is precipitated by the action of lime; Influence des phosphates, lors de la precipitation par la chaux, de l'uranium contenu dans les solutions d'attaque sulfurique du Forez

Energy Technology Data Exchange (ETDEWEB)

Brebec, G

1959-03-01

Influence of phosphates when uranium in solutions obtained by attacking Forez with sulfuric acid is precipitated by the action of lime was studied. Most of the phosphates were eliminated in the form of ferric phosphates without noticeable losses of uranium: for this it is only necessary to add sufficient ferric sulfate to the solution to be treated so that [Po{sub 4}{sup 3-}]/[Fe{sup 3+}] {approx} 0,4. In these conditions, the preparation of a calcium concentrate rich in uranium takes place in two stages. The first is neutralization at pH 2,7 to 2,8 with elimination of phosphates, sulfates and iron; the second is precipitation of the concentrate at pH 6,5. (author) [French] Nous avons reussi a eliminer la majeure partie des phosphates sous forme de phosphates ferriques, sans pertes sensibles d'uranium. Pour cela, il suffit d'ajouter a la solution a traiter, du sulfate ferrique en quantite telle que: (Po{sub 4}{sup 3-}]/[Fe{sup 3+}] {approx} 0,4. Dans ces conditions, la preparation du concentre calcique, riche en uranium, s'effectue normalement en deux temps: 1) preneutralisation a pH 2,7-2,8: elimination des sulfates, phosphates et fer; 2) precipitation du concentre a pH 6,5. (auteur)

Recovery of uranium from wet process by the chloridic leaching of phosphate rocks

International Nuclear Information System (INIS)

Santana, A.O.; Paula, H.C.B.; Dantas, C.C.

1984-01-01

Uranium was recovered from chloridic leach liquor of phosphate rocks by solvent extraction on a laboratory scale. The extractor system is a mixture of di-(2-ethylhexyl) phosphoric acid (D 2 EHPA) and tributyl-phosphate (TBP) in a varsol diluent. The uranium concentration is 150 ppm in the rocks and 12 ppm in the leach liquor. The phosphate rocks are leached on a semi-industrial scale for dicalcium phosphate production. The recovery process comprises the following steps: extraction, reextraction, iron removal and uranium precipitation. (orig./EF)

Recovery of uranium from wet process by the chloridic leaching of phosphate rocks

Energy Technology Data Exchange (ETDEWEB)

Santana, A O; Paula, H C.B.; Dantas, C C

1984-03-01

Uranium was recovered from chloridic leach liquor of phosphate rocks by solvent extraction on a laboratory scale. The extractor system is a mixture of di-(2-ethylhexyl) phosphoric acid (D/sub 2/EHPA) and tributyl-phosphate (TBP) in a varsol diluent. The uranium concentration is 150 ppm in the rocks and 12 ppm in the leach liquor. The phosphate rocks are leached on a semi-industrial scale for dicalcium phosphate production. The recovery process comprises the following steps: extraction, reextraction, iron removal and uranium precipitation.

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.

Specific binding of antigen-antibody in physiological environments: Measurement, force characteristics and analysis

Science.gov (United States)

Gu, Xin; Zhou, Jun; Zhou, Lu; Xie, Shusen; Petti, Lucia; Wang, Shaomin; Wang, Fuyan

2018-05-01

The specific recognition of the antigen by the antibody is the crucial step in immunoassays. Measurement and analysis of the specific recognition, including the ways in which it is influenced by external factors are of paramount significance for the quality of the immunoassays. Using prostate-specific antigen (PSA)/anti-PSA antibody and α-fetoprotein (AFP) /anti-AFP antibody as examples, we have proposed a novel solution for measuring the binding forces between the antigens and their corresponding antibodies in different physiological environments by combining laminar flow control technology and optical tweezers technology. On the basis of the experimental results, the different binding forces of PSA/anti-PSA antibody and AFP/anti-AFP antibody in the same phosphate-buffered saline (PBS) environments are analysed by comparing the affinity constant of the two antibodies and the number of antigenic determinants of the two antigens. In different electrolyte environments, the changes of the binding force of antigens-antibodies are explained by the polyelectrolyte effect and hydrophobic interaction. Furthermore, in different pH environments, the changes of binding forces of antigens-antibodies are attributed to the role of the denaturation of protein. The study aims to recognise the antigen-antibody immune mechanism, thus ensuring further understanding of the biological functions of tumour markers, and it promises to be very useful for the clinical diagnosis of early-stage cancer.

Monoclonal antibody hapten radiopharmaceutical delivery

International Nuclear Information System (INIS)

Goodwin, D.A.; McTigue, M.

1986-01-01

One hundred μg of monoclonal antibody (MoAb) CHA255 with a binding constant Kb of 4 x 10 9 was complexed with indium-111 labelled BLEDTA II, BLEDTA IV, benzyl EDTA, and an EDTA conjugate of Fab. The 24-h tumour and organ distribution of BALB/c mice bearing KHJJ tumours was studied for each compound alone, the antibody complex, and 3 h following a chelate chase of the antibody complex. Whole body biological half-life was measured for 7 days with and without a chelate chase for each antibody complex. The 24-h whole body counts dropped 20 to 60% and blood concentration fell over 89% within 3 h of administering the chelate chase. Theoretical equivalent human organ doses were calculated from the 24-h organ concentrations, effective half-life, and MIRD 11 S values (absorbed dose per cumulated activity). Liver and spleen were the target organs, with the dose ranging from 0.50 to 3.91 rads mCi -1 . The reduction in organ radiation dose varied up to 95% following the chelate chase. Rapid selective renal clearance of chelate labelled radiopharmaceuticals by competitive inhibition (chelate chase) of their reversible binding to monoclonal antibodies enhances tumour imaging and improves the radiation dosimetry. (author)

Renal Control of Calcium, Phosphate, and Magnesium Homeostasis

Science.gov (United States)

Chonchol, Michel; Levi, Moshe

2015-01-01

Calcium, phosphate, and magnesium are multivalent cations that are important for many biologic and cellular functions. The kidneys play a central role in the homeostasis of these ions. Gastrointestinal absorption is balanced by renal excretion. When body stores of these ions decline significantly, gastrointestinal absorption, bone resorption, and renal tubular reabsorption increase to normalize their levels. Renal regulation of these ions occurs through glomerular filtration and tubular reabsorption and/or secretion and is therefore an important determinant of plasma ion concentration. Under physiologic conditions, the whole body balance of calcium, phosphate, and magnesium is maintained by fine adjustments of urinary excretion to equal the net intake. This review discusses how calcium, phosphate, and magnesium are handled by the kidneys. PMID:25287933

Evaluation of influence of fertilizers in radium concentration from tomato culture

International Nuclear Information System (INIS)

Lauria, Dejanira C.; Ribeiro, Fernando C.A.; Alleluia, Irene B.; Perez, Daniel V.

2001-01-01

The fertilizer contribution to radio uptake by tomato plants was assessed. Tomato and soil samples from four different plantations were analyzed: two using organic fertilizer and two using phosphate fertilizer. The Ra concentrations in eight of the most used tomato fertilizers were determined. The concentration values ranged from 14 to 221 Bq/kg of Ra-226 and from 25 to 176 Bq/kg of Ra-228. Owing to the low Ra concentration and to the used fertilizer quantities, the fertilizers would not increase significantly the Ra soil concentration. However, the highest soil to plant concentration ratios were found in the plantations using phosphate fertilizers. This outcome pointed out the higher Ra availability in the phosphate fertilizer plantations than in the organic fertilizer plantations, showing a possible positive influence of phosphate fertilizers for the tomato Ra uptake. Due to the phosphate fertilizer used, the dose could increase from 0,05 Sv/year to 0,24 Sv/year. However this increase is not significant face the ingestion average worldwide effective dose. (author)

Nano zinc phosphate coatings for enhanced corrosion resistance of mild steel

International Nuclear Information System (INIS)

Tamilselvi, M.; Kamaraj, P.; Arthanareeswari, M.; Devikala, S.

2015-01-01

Highlights: • Nano zinc phosphate coating on mild steel was developed. • Nano zinc phosphate coatings on mild steel showed enhanced corrosion resistance. • The nano ZnO increases the number of nucleating sites for phosphating. • Faster attainment of steady state during nano zinc phosphating. - Abstract: Nano crystalline zinc phosphate coatings were developed on mild steel surface using nano zinc oxide particles. The chemical composition and morphology of the coatings were analyzed by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The particles size of the nano zinc phosphate coating developed was also characterized by TEM analysis. Potentiodynamic polarization and electrochemical impedance studies were carried out in 3.5% NaCl solution. Significant variations in the coating weight, morphology and corrosion resistance were observed as nano ZnO concentrations were varied from 0.25 to 2 g/L in the phosphating baths. The results showed that nano ZnO particles in the phosphating solution yielded phosphate coatings of higher coating weight, greater surface coverage and enhanced corrosion resistance than the normal zinc phosphate coatings (developed using normal ZnO particles in the phosphating baths). Better corrosion resistance was observed for coatings derived from phosphating bath containing 1.5 g/L nano ZnO. The activation effect brought about by the nano ZnO reduces the amount of accelerator (NaNO 2 ) required for phosphating

Measurement of cyclosporine concentrations in whole blood: HPLC and radioimmunoassay with a specific monoclonal antibody and 3H- or 125I-labeled ligand compared

International Nuclear Information System (INIS)

Wolf, B.A.; Daft, M.C.; Koenig, J.W.; Flye, M.W.; Turk, J.W.; Scott, M.G.

1989-01-01

We compared cyclosporine concentrations in whole blood as measured by HPLC and by RIA with a monoclonal antibody specific for cyclosporine with 3 H- or 125 I-labeled cyclosporine ligand. The 3 H-RIA kit slightly underestimated cyclosporine concentrations (greater than 600 micrograms/L) in comparison with HPLC. Over a wide range of concentrations, cyclosporine measured with the 125 I-RIA kit correlated well with HPLC (slope = 0.99, n = 301, r = 0.98), observed for samples from recipients of kidney, heart, or liver allografts (respective slopes: 1.01, 0.93, and 1.00). The 125 I-RIA standard curve was linear to 1000 micrograms of cyclosporine per liter. Inter- and intra-assay CVs for 125 I-RIA measurements of cyclosporine were less than or equal to 7%. Evidently, the 125 I-RIA kit involving a monoclonal antibody specific for cyclosporine is equivalent to the HPLC assay and can replace it for therapeutic drug monitoring of cyclosporine therapy

Serum phosphate is an early predictor of outcome in severe acetaminophen-induced hepatotoxicity

DEFF Research Database (Denmark)

Schmidt, Lars E; Dalhoff, Kim

2002-01-01

Hypophosphatemia is frequently observed in acetaminophen-induced hepatotoxicity and may be involved in the pathogenesis of hepatic failure. The aim of the study was to evaluate the prognostic value of serial measurements of serum phosphate in patients with severe acetaminophen poisoning. Prospect......Hypophosphatemia is frequently observed in acetaminophen-induced hepatotoxicity and may be involved in the pathogenesis of hepatic failure. The aim of the study was to evaluate the prognostic value of serial measurements of serum phosphate in patients with severe acetaminophen poisoning...... Hospital (KCH) criteria. Phosphate concentrations were significantly higher in nonsurvivors than in survivors at 48 to 72 hours after overdose (mean 2.65 +/- 1.18 mmol/L vs. 0.68 +/- 0.22 mmol/L, P L vs. 0.59 +/- 0.23 mmol/L, P ...). A threshold phosphate concentration of 1.2 mmol/L at 48 to 96 hours after overdose had sensitivity 89%, specificity 100%, accuracy 98%, positive predictive value 100%, and negative predictive value 98%. The phosphate criteria had higher sensitivity, accuracy, and positive and negative predictive values than...

Direct binding of radioiodinated monoclonal antibody to tumor cells: significance of antibody purity and affinity for drug targeting or tumor imaging

International Nuclear Information System (INIS)

Kennel, S.J.; Foote, L.J.; Lankford, P.K.; Johnson, M.; Mitchell, T.; Braslawsky, G.R.

1983-01-01

For MoAb to be used efficiently for drug targeting and tumor imaging, the fraction of antibody binding to tumor cells must be maximized. The authors have studied the binding of 125 I MoAb in three different tumor systems. The fraction of antibody that could be bound to the cell surface was directly proportional to the antibody purity. The affinity constant also limits the fraction of antibody that can bind to cells at a given antigen concentration. Rearrangement of the standard expression for univalent equilibrium binding between two reactants shows that in antigen excess, the maximum fraction of antibody that can bind =Ka[Ag total]/1 + Ka[Ag total]. Binding data using four different MoAb with three cell systems confirm this relationship. Estimates for reasonable concentrations of tumor antigens in vivo indicate that antibodies with binding constants less than 10 8 M -1 are not likely to be useful for drug targeting or tumor imaging

Availability of metals in samples of phosphogypsum and phosphate fertilizers used in agriculture

International Nuclear Information System (INIS)

Bourlegat, Fernanda Melo le

2010-01-01

The Brazilian phosphate fertilizer is obtained by wet reaction of the igneous phosphate rock with concentrated sulphuric acid, giving as final product, phosphoric acid, and dehydrated calcium sulphate (phosphogypsum) as by-product. Part of this phosphogypsum is stored in stacks at open air and part has been used in agriculture, as soil amendment. To assure a safe utilization of phosphogypsum it is important to determine the levels of impurities, particularly of metals, present in phosphogypsum. In this paper, the concentration of metals (As, Ba, Cd, Cr, Co, Cu, Hg, Ni, Pb, Se, Zn and rare earth elements) present in Brazilian phosphogypsum and also in single super phosphate (SSP), triple super phosphate (TSP), monoammonium phosphate (MAP) and diammonium phosphate (DAP) were determined. The metals Cd, Cu, Ni, Pb and Zn were determined following the procedure 'EPA 3052'. The same elements, As and Se were also determined following the procedure 'EPA 3050B', recommended by Ministerio da Agricultura, Pecuaria e Abastecimento (MAPA). All these metals are controlled by environmental and agriculture regulation institutes in Brazil. The concentrations obtained for the metals analyzed by using the two procedures were different. Ba, Co, Cr and rare earth elements were determined by neutron activation analysis. In order to evaluate the availability of these metals As, Cd, Cr, Co, Cu, Ni, Pb, Se and Zn to the environment, the content of the same elements were determined following a procedure established by the EC (European Community), which includes an initial attack of the samples with EDTA-NH 4 0.05M, at pH 7.0. In all these cases, phosphogypsum presented metals concentration lower than the phosphate fertilizers, and the results are below the limits adopted by MAPA and Companhia Ambiental do Estado de Sao Paulo (CETESB). The results obtained using the methodology with mild attack show that the metals are not available to the environment, giving evidence that the application of

Characterization of a monoclonal antibody to thymidine glycol monophosphate

International Nuclear Information System (INIS)

Chen, B.X.; Hubbard, K.; Ide, H.; Wallace, S.S.; Erlanger, B.F.

1990-01-01

A monoclonal antibody specific for thymine glycol (TG) in irradiated or OsO4-treated DNA was obtained by immunizing with thymidine glycol monophosphate (TMP-glycol) conjugated to bovine serum albumin by a carbodiimide procedure. Screening by dot-immunobinding and enzyme-linked immunosorbant assay (ELISA) procedures gave eight clones that bound OsO4- treated DNA. One of them, 2.6F.6B.6C, an IgG2a kappa, was characterized further. Hapten inhibition studies with OsO4-treated DNA showed that the antibody was specific for TMP-glycol. Among the various inhibitors tested, inhibition was in the order TMP-glycol greater than 5,6-dihydrothymidine phosphate greater than TMP greater than thymidine glycol greater than TG. Inhibition by 5,6-dihydrothymidine, thymidine, thymine, AMP, and CMP was negligible. In OsO4-treated DNA, as few as 0.5 TG per 10,000 bp were detectable by direct ELISA. Inhibition assays could detect as few as 1.5 TG per 10,000 bp. The antibody was equally reactive with native or denatured DNA containing TG. Among the X-irradiated homopolymers dC, dA, dG, and dT, only dT reacted with the antibody. Using an ELISA, the antibody could detect damage in irradiated DNA at the level of 20 Gy. Thus the antibody is of potential use in assays for DNA damage caused by X rays or other agents that damage DNA by free radical interactions

Dibasic Ammonium Phosphate Application Enhances Aromatic Compound Concentration in Bog Bilberry Syrup Wine

Directory of Open Access Journals (Sweden)

Shao-Yang Wang

2016-12-01

Full Text Available A nitrogen deficiency always causes bog bilberry syrup wine to have a poor sensory feature. This study investigated the effect of nitrogen source addition on volatile compounds during bog bilberry syrup wine fermentation. The syrup was supplemented with 60, 90, 120 or 150 mg/L dibasic ammonium phosphate (DAP before fermentation. Results showed that an increase of DAP amounts accelerated fermentation rate, increased alcohol content, and decreased sugar level. Total phenol and total flavonoid content were also enhanced with the increase of DAP amounts. A total of 91 volatile compounds were detected in the wine and their concentrations were significantly enhanced with the increase of DAP. Ethyl acetate, isoamyl acetate, phenethyl acetate, ethyl butanoate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, isobutanol, isoamyl alcohol, levo-2,3-butanediol, 2-phenylethanol, meso-2,3-butanediol, isobutyric acid, hexanoic acid, and octanoic acid exhibited a significant increase of their odor activity value (OAV with the increase of DAP amounts. Bog bilberry syrup wine possessed fruity, fatty, and caramel flavors as its major aroma, whereas a balsamic note was the least present. The increase of DAP amounts significantly improved the global aroma attributes, thereby indicating that DAP supplementation could promote wine fermentation performance and enhance the sensory quality of bog bilberry syrup wine.

Water diffusion in phosphate-containing hydrogels

International Nuclear Information System (INIS)

George, K.A.; Wentrup-Byrne, E.; Hill, D.J.T.; Whittaker, A.K.

2003-01-01

An understanding of the kinetics and diffusion of liquids through polymeric hydrogels is critical for the successful design and application of these materials in biomedical field, particularly as controlled drug delivery systems. In this study, the mechanisms of water transport and parameters that describe the diffusion process in crosslinked poly(2-hydroxyethylmethacrylate-co-methyloxyethylene phosphate), poly(HEMA-co-MOEP) polymers were investigated. The copolymerisation of HEMA with MOEP was initiated by γ radiolysis with full conversion of monomer to polymer. The sorption of water into the polymers with 0 - 30 mol% MOEP was monitored gravimetrically over a period of 2 - 3 weeks. This study provided an insight into the diffusion mechanism and showed that the PHEMA hydrogel displayed concentration-independent Fickian diffusion. As the concentration of MOEP in the network increased, the diffusion rate and the rigidity of the network also increased in a linear fashion. NMR imaging was used in conjunction with the gravimetric study to elucidate the transport mechanisms, diffusion coefficients and proportionality constants governing the water diffusion in the phosphate-containing polymers. The hydrogels with 3 - 20 mol% MOEP exhibited exponential concentration-dependent Fickian diffusion and the transport mechanism in the system with 30 mol% MOEP was shown to be anomalous. The systems with greater concentrations of MOEP displayed a high degree of fracturing during water sorption and resulted in the ultimate destruction of the cylindrical geometry

ION EXCHANGE SUBSTANCES BY SAPONIFICATION OF ALLYL PHOSPHATE POLYMERS

Science.gov (United States)

Kennedy, J.

1959-04-14

An ion exchange resin having a relatively high adsorption capacity tor uranyl ion as compared with many common cations is reported. The resin comprises an alphyl-allyl hydrogen phosphate polymer, the alphyl group being either allyl or a lower alkyl group having up to 5 carbon atoins. The resin is prepared by polymerizing compounds such as alkyl-diallyl phosphate and triallyl phosphate in the presence of a free radical generating substance and then partially hydrolyzing the resulting polymer to cause partial replacement of organic radicals by cations. A preferred free radical gencrating agent is dibenzoyl peroxide. The partial hydrolysis is brought about by refluxing the polymer with concentrated aqueous NaOH for three or four hours.

Inorganic phosphate inhibits sympathetic neurotransmission in canine saphenous veins

International Nuclear Information System (INIS)

Edoute, Y.; Vanhoutte, P.M.; Shepherd, J.T.

1987-01-01

Inorganic phosphate has been proposed as the initiator of metabolic vasodilatation in active skeletal muscle. The present study was primarily designed to determine if this substance has an inhibitory effect on adrenergic neurotransmission. Rings of canine saphenous veins were suspended for isometric tension recording in organ chambers. A comparison was made of the ability of inorganic phosphate (3 to 14 mM) to relax rings contracted to the same degree by electrical stimulation, exogenous norepinephrine, and prostaglandin F/sub 2α/. The relaxation during electrical stimulation was significantly greater at all concentrations of phosphate. In strips of saphenous veins previously incubated with [ 3 H]norepinephrine, the depression of the contractile response caused by phosphate during electrical stimulated was accompanied by a significant reduction in the overflow of labeled neurotransmitter. Thus inorganic phosphate inhibits sympathetic neurotransmission and hence may have a key role in the sympatholysis in the active skeletal muscles during exercise. By contrast, in this preparation, it has a modest direct relaxing action on the vascular smooth muscle

Phosphate dissolving fungi: Mechanism and application in alleviation of salt stress in wheat.

Science.gov (United States)

Gaind, Sunita

2016-12-01

The present investigation reveals the solubilization efficiency of tri-calcium phosphate (TCP), Udaipur rock phosphate (URP), aluminium phosphate (AP) and ferric phosphate (FP) by Aspergillus niger (ITCC 6719) and Trichoderma harzianum (ITCC 6721) as function of carbon concentrations. Increasing glucose concentration from 1 to 7% in the growth medium, though improved the phosphorus (P) solubilization significantly but each fungal strain preferred different optimum carbon concentrations for mediating solubilization of different P sources. The two fungi employed different mechanisms to reduce medium pH for release of P from TCP, AP and FP. However, URP was solubilized solely through fungal production of citric, succinic, propionic, malic and acetic acid. A linear increase in citric acid production with increasing carbon concentration was recorded during FP solubilization by T. harzianum. The cell free culture filtrate of A. niger detected high phytase and low acid phosphatase activity titre whereas results were vice versa for T. harzianum. Both the fungal strains possessed plant growth promoting attributes such as auxin and sidreophore production and could solubilize Zn. In hydroponic system (with 60mM of sodium chloride concentration), supplementation with culture filtrate from each fungal strain increased the shoot growth of wheat seedlings significantly compared to non culture filtrate control. Use of A.niger as bio-inoculant could be a sustainable approach to improve soil P availability, promote plant growth and alleviate adverse effect of salt stress. Copyright © 2016 Elsevier GmbH. All rights reserved.

Phosphate-assisted phytoremediation of arsenic by Brassica napus and Brassica juncea: Morphological and physiological response.

Science.gov (United States)

Niazi, Nabeel Khan; Bibi, Irshad; Fatimah, Ayesha; Shahid, Muhammad; Javed, Muhammad Tariq; Wang, Hailong; Ok, Yong Sik; Bashir, Safdar; Murtaza, Behzad; Saqib, Zulfiqar Ahmad; Shakoor, Muhammad Bilal

2017-07-03

In this study, we examined the potential role of phosphate (P; 0, 50, 100 mg kg -1 ) on growth, gas exchange attributes, and photosynthetic pigments of Brassica napus and Brassica juncea under arsenic (As) stress (0, 25, 50, 75 mg kg -1 ) in a pot experiment. Results revealed that phosphate supplementation (P100) to As-stressed plants significantly increased shoot As concentration, dry biomass yield, and As uptake, in addition to the improved morphological and gas exchange attributes and photosynthetic pigments over P0. However, phosphate-assisted increase in As uptake was substantially (up to two times) greater for B. napus, notably due to higher shoot As concentration and dry biomass yield, compared to B. juncea at the P100 level. While phosphate addition in soil (P100) led to enhanced shoot As concentration in B. juncea, it reduced shoot dry biomass, primarily after 50 and 75 mg kg -1 As treatments. The translocation factor and bioconcentration factor values of B. napus were higher than B. juncea for all As levels in the presence of phosphate. This study demonstrates that phosphate supplementation has a potential to improve As phytoextraction efficiency, predominantly for B. napus, by minimizing As-induced damage to plant growth, as well as by improving the physiological and photosynthetic attributes.

Discrimination of fluoride and phosphate contamination in central Florida for analyses of environmental effects

Science.gov (United States)

Coker, A. E.; Marshall, R.; Thomson, F.

1972-01-01

A study was made of the spatial registration of fluoride and phosphate pollution parameters in central Florida by utilizing remote sensing techniques. Multispectral remote sensing data were collected over the area and processed to produce multispectral recognition maps. These processed data were used to map land areas and waters containing concentrations of fluoride and phosphate. Maps showing distribution of affected and unaffected vegetation were produced. In addition, the multispectral data were processed by single band radiometric slicing to produce radiometric maps used to delineate areas of high ultraviolet radiance, which indicates high fluoride concentrations. The multispectral parameter maps and radiometric maps in combination showed distinctive patterns, which are correlated with areas known to be affected by fluoride and phosphate contamination. These remote sensing techniques have the potential for regional use to assess the environmental impact of fluoride and phosphate wastes in central Florida.

Antimicrobial activity of polyhexamethylene guanidine phosphate in comparison to chlorhexidine using the quantitative suspension method.

Science.gov (United States)

Vitt, A; Sofrata, A; Slizen, V; Sugars, R V; Gustafsson, A; Gudkova, E I; Kazeko, L A; Ramberg, P; Buhlin, K

2015-07-17

Polyhexamethylene guanidine phosphate (PHMG-P) belongs to the polymeric guanidine family of biocides and contains a phosphate group, which may confer better solubility, a detoxifying effect and may change the kinetics and dynamics of PHMG-P interactions with microorganisms. Limited data regarding PHMG-P activity against periodontopathogenic and cariogenic microorganisms necessitates studies in this area. Aim is to evaluate polyhexamethylene guanidine phosphate antimicrobial activity in comparison to chlorhexidine. Quantitative suspension method was used enrolling Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Streptococcus mutans and Lactobacillus acidophilus. Both tested antiseptics at their clinically-used concentrations, of 0.2% (w/v) and 1% (w/v), correspondingly provided swift bactericidal effects against S. aureus, P. aeruginosa, E. coli and C. albicans, A. actinomycetemcomitans and P. gingivalis with reduction factors higher than 6.0. Diluted polyhexamethylene guanidine phosphate and chlorhexidine to 0.05% continued to display anti-bacterial activity and decreased titers of standard quality control, periopathogens to below 1.0 × 10(3) colony forming units/ml, albeit requiring prolonged exposure time. To achieve a bactericidal effect against S. mutans, both antiseptics at all concentrations required a longer exposure time. We found that a clinically-used 1% of polyhexamethylene guanidine phosphate concentration did not have activity against L. acidophilus. High RF of polyhexamethylene guanidine phosphate and retention of bactericidal effects, even at 0.05%, support the use of polyhexamethylene guanidine phosphate as a biocide with sufficient anti-microbial activity against periopathogens. Polyhexamethylene guanidine phosphate displayed bactericidal activity against periopathogens and S. mutans and could potentially be applied in the management of oral

Dimensional stability under wet curing of mortars containing high amounts of nitrates and phosphates

International Nuclear Information System (INIS)

Benard, P.; Cau Dit Coumes, C.; Garrault, S.; Nonat, A.; Courtois, S.

2008-01-01

Investigations were carried out in order to solidify in cement some aqueous streams resulting from nuclear decommissioning processes and characterized by a high salinity (300 g/L), as well as important concentrations of nitrate (150-210 g/L) and phosphate ions (0-50 g/L). Special attention was paid to the influence of these compounds on the dimensional variations under wet curing of simulated solidified waste forms. The length changes of mortars containing nitrate salts only (KNO 3 , NaNO 3 ) were shown to be governed by a concentration effect which involved osmosis: the higher their concentration in the mixing solution, the higher the swelling. The expansion of mortars containing high amounts of phosphates (≥ 30 g/L in the mixing solution) was preceded by a shrinkage which increased with the phosphate concentration, and which could be suppressed by seeding the cement used with hydroxyapatite crystals. This transitory shrinkage was attributed to the conversion into hydroxyapatite of a precursor readily precipitated in the cement paste after mixing

Study on quantification of HBs-antibody by immunoradiometric assay

International Nuclear Information System (INIS)

Kondo, Yuichi; Itoi, Yoshihiro; Kajiyama, Shizuo

1989-01-01

Quantification of HBs-antibody assay was carried out using a commercialized assay kit and standard solutions of HBs-antibody recognised as 1 st reference preparation of hepatitis B immunogloblin by WHO. Standard curve of HBs-antibody was drawn with the function of 3D-spline and the correlation factor was obtained as r = 0.999. Coefficient of intra-assay variance was 3.8 % and that of inter-assay variance was 7.8 %. Dilution tests showed satisfactory results in the range of 2-16 times. Correlation between value of cut-off indices and concentration of HBs-antibody was obtained as the formula of y = 2.599 x-3.894 (r = 0.992) and 2.1 of cut-off index corresponded to about 5 mIU/ml of HBs-antibody concentration. (author)

Elemental and radionuclides distribution in the production and use of phosphate fertilizers in Brazil

International Nuclear Information System (INIS)

Saueia, Catia Heloisa Rosignoli

2006-01-01

Fertilizer is considered an essential component for agriculture, because its use increases the natural soil nutrients, which are lost slow waste or erosion. The Brazilian phosphate fertilizer is obtained by wet reaction of igneous phosphate rock with concentrated sulphuric acid, giving as final product, phosphoric acid and dihydrated calcium sulphate (phosphogypsum) as by-product. Phosphoric acid is the starting material for triple superphosphate (TSP), single superphosphate (SSP), monoammonium phosphate (MAP) and diammonium phosphate (DAP). The phosphate rock used as raw material presents in its composition, radionuclides of the U and Th natural series in. During the chemical attack of the phosphate rock, this equilibrium is disrupted and the radionuclides and the elements migrate to intermediate, final products and byproducts, according to their solubility and chemical properties. While the fertilizers are commercialized, the phosphogypsum is disposed in stack piles and can cause an impact in the environment. In order to evaluate the radionuclides and the elements distribution in the industrial process of phosphate fertilizer production, samples of concentrated rock, fertilizers (SSP, TSP, MAP and DAP) and phosphogypsum from three national industries (A, B and C), were analyzed. The characterization of the elements Ba, Co, Cr, Fe, Hf, Na, Sc, Ta, Th, U, Zn and Zr, and the rare earths La, Ce, Nd, Sm, Eu, Tb, Yb and Lu, were performed by instrumental neutron activation analysis. The results obtained showed that, in general, the rare earth elements are distributed uniformly in the fertilizers and phosphogypsum, except for Lu. The elemental concentration present in the fertilizers SSP and TSP are of the same order of magnitude of the source rock. The same behavior was observed in the fertilizers MAP and DAP, except for the elements Co, Sc and U. The radionuclides of the U series ( 238 U, 234 U, 230 Th, 226 Ra, 210 Pb) and of the Th series ( 232 Th, 228 Ra, 228 Th

Transmission spectra study of sulfate substituted potassium dihydrogen phosphate

KAUST Repository

LI, LIANG; Zhang, Jianqin; Sun, Xun; Zhang, Qiang; Zhao, Xian; Zhang, Xixiang

2013-01-01

Potassium dihydrogen phosphate (KDP) crystals with different amounts of sulfate concentration were grown and the transmittance spectrum was studied. A crystal with high sulfate replacement density exhibits heavy absorption property

Measurement of radium - 226 in rock phosphate used as low cost fertilizer using gamma spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Ahmed, M M.O.; Mohamed, O S [Atomic Energy Research Institute, Box 3001, Khartoum, (Sudan); Eltib, A E; Allasaad, I A.A. [faculty of Agriculture, University of Khartoum, (Sudan)

1995-10-01

This study was carried out to determine the concentration of radium - 226 in rock phosphate (used as low cost fertilizer), soil and plant. Two types of rock phosphates were examined, namely, Uro and kurun area in the Nuba mountains located in the western part of the sudan. The work included the determination of {sup 226} Ra levels in soil after applying different concentration of rock phosphate in pot experiments. The plant used was Abu sabien a sorghum which used for the animal feed. {sup 226} Ra in the soil using 20 g/pot (1000 kg/fed). of rock phosphate was found to be 88 and 104 Bq/kg for and 45 and 72 Bq/kg for kurun for season one and three respectively. As for the plant the concentration was found to be 1.2 and 1.4 Bq/kg for Uro and 0.4 and 0.6 Bq/kg for kurun for the first and third seasons respectively. The transfer factor of {sup 226} Ra from soil to plant was estimated to be (0.01). The concentration of {sup 226} Ra in the plant was found to be below the recommended values of contamination. 4 figs.

Measurement of radium - 226 in rock phosphate used as low cost fertilizer using gamma spectroscopy

International Nuclear Information System (INIS)

Ahmed, M.M.O.; Mohamed, O.S.; Eltib, A.E.; Allasaad, I.A.A.

1995-01-01

This study was carried out to determine the concentration of radium - 226 in rock phosphate (used as low cost fertilizer), soil and plant. Two types of rock phosphates were examined, namely, Uro and kurun area in the Nuba mountains located in the western part of the sudan. The work included the determination of 226 Ra levels in soil after applying different concentration of rock phosphate in pot experiments. The plant used was Abu sabien a sorghum which used for the animal feed. 226 Ra in the soil using 20 g/pot (1000 kg/fed). of rock phosphate was found to be 88 and 104 Bq/kg for and 45 and 72 Bq/kg for kurun for season one and three respectively. As for the plant the concentration was found to be 1.2 and 1.4 Bq/kg for Uro and 0.4 and 0.6 Bq/kg for kurun for the first and third seasons respectively. The transfer factor of 226 Ra from soil to plant was estimated to be (0.01). The concentration of 226 Ra in the plant was found to be below the recommended values of contamination. 4 figs

Mechanism of calcium phosphates precipitation in liquid crystals

International Nuclear Information System (INIS)

Prelot, B.; Zemb, T.

2004-04-01

The possibility of using as a precursor an easily wet meso-porous powder would be a breakthrough in the preparation of nuclear waste storage ceramics. A concentrated solution containing ions to be stored would wet a dry powder and then, subjected to mild compression, lead to a micro-crystalline matrix of calcium phosphate at acceptable temperatures. Since no porous calcium phosphate different from calcined bone (patented) is described as porous precursor, we have compared the different synthesis routes towards meso-porous ceramics. First, we considered homogeneous precipitation of slats in water: using initially off-stoichiometry in reaction, micron-sized hydroxyapatite particles are produced with a specific surface up to 100 m 2 /g. Then, we consider the classical route of precipitation of an hybrid material in the miscibility gap of a phase diagram, when an hexagonal liquid crystal is used a matrix for precipitation. The surfactant family consists in single chain surfactants containing phosphates as head-group to poison the growing surface of calcium phosphate nano-domains. Since the reaction is still too brutal, we considered using a cat-anionic precursor material of controllable surface charge. For certain concentrations and molar ratios, a new structure not yet described in surfactant precipitation literature is observed: since the periodicity is lower than twice the chain length, a disordered constant curvature monolayer (instead of the classical cylinder of twice chain length diameter) of surfactant is implied. Finally, we have investigated synthesis routes implying slow dissolution of pre-formed calcium phosphate in an already existing hexagonal matrix. For all these routes of synthesis, micro-structural determinations using SAXS, WARS and BET are performed, with a special attention to comparison of the precipitation material, the matrix obtained with all elements present, and also the material obtained after calcinations. (authors)

Concentration dependent spectroscopic properties of Dy{sup 3+} ions doped boro-phosphate glasses

Energy Technology Data Exchange (ETDEWEB)

Mariyappan, M.; Marimuthu, K., E-mail: mari-ram2000@yahoo.com [Department of Physics, Gandhigram Rural Institute - Deemed University, Gandhigram – 624 302 (India)

2016-05-23

Dy{sup 3+} ions doped boro-phosphate glasses have been synthesized by melt quenching method and characterized through FTIR, absorption and luminescence spectral measurements. The presence of various stretching and bending vibrations of different borate and phosphate groups were identified from the FTIR spectra. In order to examine the electronic band structure of the studied glasses, Optical energy gap (E{sub opt}) and Urbach energy (ΔE) values were estimated from the absorption spectra. The Judd-Ofelt (JO) intensity parameters were calculated to examine the symmetry of the ligand environment around the Dy{sup 3+} ions site. The emission spectra exhibit two intense emission bands at around 482 nm (blue) and 574 nm (yellow) corresponding to the {sup 4}F{sub 9/2}→{sup 6}H{sub 15/2} and {sup 4}F{sub 9/2}→{sup 6}H{sub 13/2} transitions respectively. The emission spectra were characterized through Commission International d’Eclairage (CIE) 1931 chromaticity diagram to explore its suitability for WLED applications.

Development of nano SiO2 incorporated nano zinc phosphate coatings on mild steel

International Nuclear Information System (INIS)

Tamilselvi, M.; Kamaraj, P.; Arthanareeswari, M.; Devikala, S.; Selvi, J. Arockia

2015-01-01

Highlights: • Nano SiO 2 incorporated nano zinc phosphate coating on mild steel was developed. • Coatings showed enhanced corrosion resistance. • The nano SiO 2 is adsorbed on mild steel surface and become nucleation sites. • The nano SiO 2 accelerates the phosphating process. - Abstract: This paper reports the development of nano SiO 2 incorporated nano zinc phosphate coatings on mild steel at low temperature for achieving better corrosion protection. A new formulation of phosphating bath at low temperature with nano SiO 2 was attempted to explore the possibilities of development of nano zinc phosphate coatings on mild steel with improved corrosion resistance. The coatings developed were studied by Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDX), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Electrochemical measurements. Significant variation in the coating weight, morphology and corrosion resistance was observed as nano SiO 2 concentrations varied from 0.5–4 g/L. The results showed that, the nano SiO 2 in the phosphating solution changed the initial potential of the interface between mild steel substrate and phosphating solution and reduce the activation energy of the phosphating process, increase the nucleation sites and yielded zinc phosphate coatings of higher coating weight, greater surface coverage and enhanced corrosion resistance. Better corrosion resistance was observed for coatings derived from phosphating bath containing 1.5 g/L nano SiO 2 . The new formulation reported in the present study was free from Ni or Mn salts and had very low concentration of sodium nitrite (0.4 g/L) as accelerator

A High-Throughput Antibody-Based Microarray Typing Platform

Directory of Open Access Journals (Sweden)

Ashan Perera

2013-05-01

Full Text Available Many rapid methods have been developed for screening foods for the presence of pathogenic microorganisms. Rapid methods that have the additional ability to identify microorganisms via multiplexed immunological recognition have the potential for classification or typing of microbial contaminants thus facilitating epidemiological investigations that aim to identify outbreaks and trace back the contamination to its source. This manuscript introduces a novel, high throughput typing platform that employs microarrayed multiwell plate substrates and laser-induced fluorescence of the nucleic acid intercalating dye/stain SYBR Gold for detection of antibody-captured bacteria. The aim of this study was to use this platform for comparison of different sets of antibodies raised against the same pathogens as well as demonstrate its potential effectiveness for serotyping. To that end, two sets of antibodies raised against each of the “Big Six” non-O157 Shiga toxin-producing E. coli (STEC as well as E. coli O157:H7 were array-printed into microtiter plates, and serial dilutions of the bacteria were added and subsequently detected. Though antibody specificity was not sufficient for the development of an STEC serotyping method, the STEC antibody sets performed reasonably well exhibiting that specificity increased at lower capture antibody concentrations or, conversely, at lower bacterial target concentrations. The favorable results indicated that with sufficiently selective and ideally concentrated sets of biorecognition elements (e.g., antibodies or aptamers, this high-throughput platform can be used to rapidly type microbial isolates derived from food samples within ca. 80 min of total assay time. It can also potentially be used to detect the pathogens from food enrichments and at least serve as a platform for testing antibodies.

Critical micelle concentration of surfactants in aqueous buffered and unbuffered systems

International Nuclear Information System (INIS)

Fuguet, Elisabet; Rafols, Clara; Roses, Marti; Bosch, Elisabeth

2005-01-01

Critical micelle concentration (CMC) of sodium dodecyl sulphate (SDS), lithium perfluorooctanesulfonate (LPFOS), hexadecyltrimethylammonium bromide (HTAB), tetradecyltrimethylammonium bromide (TTAB), and sodium cholate (SC), surfactants commonly used as pseudostationary phases in micellar electrokinetic chromatography (MEKC), have been determined by means of three different methods: MEKC, spectrophotometry, and conductometry. Determinations have been performed in water, and also in different concentrations of phosphate buffer at pH 7.0. CMC values ranging from 8.08 (water) to 1.99 (50 mM phosphate buffer) mM for SDS, from 7.16 (water) to 2,81 (30 mM phosphate buffer) mM for LPFOS, from 3.77 (water) to 1.93 (20 mM phosphate buffer) mM for TTAB, from 0.91 (water) to ∼0.34 (20 mM phosphate buffer) for HTAB, and around 13 mM (20 mM phosphate buffer) for SC, are obtained. The effect of the electrolyte concentration on the CMC, as well as the linear relationship between the electrolyte counter-ion concentration and the CMC are discussed. This linear relationship provides an easy way for users to estimate the CMC of a MEKC system, at a given electrolyte concentration. A comparison between experimental methods, as well as a discussion about the suitability of a given method for the determination of the CMC for a given surfactant system is also provided

Relevance of histamine and tryptase concentrations in nasal secretions after nasal challenges with phosphate buffered saline and allergen

Directory of Open Access Journals (Sweden)

D. Wang

1995-01-01

Full Text Available In this prospective study, a quantitative determination of histamine and tryptase in nasal secretions after nasal phosphate buffered saline (PBS and allergen challenge was performed in 18 atopic patients who were compared with ten non-allergic healthy volunteers. The aim of the study was to determine the normal and pathological concentrations of these important mediators in nasal secretions. The second objective was to test the relevance of these two mast cell secreted mediators after nasal challenge. Results showed that the concentrations of tryptase in almost all samples were under the minimal detection limit (< 0.5 μU/g and only a sigrtificant increase of tryptase (median, 28 μU/g occurred immediately after nasal allergen challenge in the patient group. Histamine concentration significantly increased after every nasal PBS challenge (median, 69 ng/g after first PBS challenge and 165 ng/g after second PBS challenge in the control group, as well as in the patient group after both PBS (median, 69 ng/g and allergen (median, 214 ng/g challenge. On the other hand, a rapid onset of sneezing and increase in nasal airway resistance was experienced only in the patient group after nasal allergen challenge, but did not occur after PBS challenge even though the histamine concentrations significantly increased in both groups. This study suggests that tryptase is a more preferable marker than histamine in quantitative monitoring of mast cell activation especially during the early phase nasal allergic reaction.

Standardization of methodology to derivatization and radiolabeling of the anti-CD20 monoclonal antibody from bifunctional chelator DOTA-NHS-Ester

International Nuclear Information System (INIS)

Massicano, Adriana V.F.; Akanji, Akinkunmi G.; Santos, Josefina S.; Pujatti, Priscilla B.; Couto, Renata M.; Massicano, Felipe; Araujo, Elaine Bortoleti de

2009-01-01

Lymphomas are cancers of the lymphatic system, being the most common the non-Hodgkin lymphoma (NHL). The Radioimmunotherapy (RIT), that increase the cytotoxic effect of monoclonal antibodies (mAb), therefore labeling these Mab with different radioisotopes. RIT combines the specificity of the antibody and the toxicity of the radionuclides. The mAb anti-CD20 is used for treatment of relapse or refractory NHL. The labeling of anti- CD20 with 177 Lu, requires a bifunctional chelating agent that is designed to make a 'connect bridge' between the mAb and the radionuclide. The incorporation of the chelating group in mAb structure is called derivatization. The aim of this work is to study the derivatization of anti-CD20 antibody with DOTA-NHS-ester chelating group and labeling parameters to produce 177 Lu-DOTA-Anti CD20. Five milligrams of anti-CD20 were purified by dialysis against phosphate buffer pH 8.0 and derivatized with DOTA-NHS-ester in 1:250, 1:500 and 1:1000 molar ratios. The reaction was conducted for 1 hour in gently mixing at room temperature and remained under refrigeration for 48 hours. The reaction mixture was purified in gel column Sephadex G-50 ; the aliquots that presented greater protein concentration, were mixed and concentrated. The purified antibody conjugated was added to 111-185MBq (3-5mCi) of 177 LuCl3 diluted in 0.4 M acetate buffer pH 5.5. Radiochemical purity was less than 95% in all the molar ratios, indicating necessity of the purification after the labeling. The mAb derivatized showed stable when stored for to 1 month to 4 deg C and 4 days at -20 deg C. (author)

Molecular Dynamics Simulation of the Structure and Properties of Lithium Phosphate Glasses

Energy Technology Data Exchange (ETDEWEB)

Liang, J-J; Cygan, R.T.; Alam, T.M.

1999-07-09

A new forcefield model was developed for the computer simulation of phosphate materials that have many important applications in the electronics and biomedical industries. The model provides a fundamental basis for the evaluation of phosphate glass structure and thermodynamics. Molecular dynamics simulations of a series of lithium phosphate glass compositions were performed using the forcefield model. A high concentration of three-membered rings (P{sub 3}O{sub 3}) occurs in the glass of intermediate composition (0.2 Li{sub 2}O {center_dot} 0.8P{sub 2}O{sub 5}) that corresponds to the minimum in the glass transition temperature curve for the compositional series. Molecular orbital calculations of various phosphate ring clusters indicate an increasing stabilization of the phosphate ring structure going from two- to four-membered rings.

Ambient Temperature Flotation of Sedimentary Phosphate Ore Using Cottonseed Oil as a Collector

Directory of Open Access Journals (Sweden)

Yaoyang Ruan

2017-04-01

Full Text Available The mid-low grade sedimentary phosphate ore, abundant in silicate and carbonate gangue minerals, exhibits a poor processability. It is conventionally enriched using high temperature flotation to remove silicate gangues with fatty acid as a collector. Cottonseed oil has been proved to be an efficient collector for achieving ambient temperature flotation of the sedimentary phosphate ore used in this study. Flotation kinetics was investigated to ascertain the excellent collecting performance of cottonseed oil, as compared with oleic acid, and the phosphate flotation fitted well with the first-order flotation model. Based on the analysis of flotation reagent effect on the direct flotation process using the response surface methodology (RSM, a closed circuit of direct-reverse flotation for stepwise removing silicate and carbonate gangues from the sedimentary phosphate ore was established. Consequently, a required high quality of phosphate concentrate containing 30.16% P2O5 was obtained, with a recovery of 90.90%. Scanning electron microscopy (SEM and X-ray diffraction analysis (XRD of the flotation products confirmed that the majority of silicate and carbonate gangues were effectively removed from the concentrate products.

Radium and uranium in phosphate fertilizers and their impact on the radioactivity of waters

International Nuclear Information System (INIS)

Barisic, D.; Lulic, S.; Miletic, P.

1992-01-01

The study of radioactivity in the phosphate fertilizers and water ways of the Kanovci area was performed in order to determine the influence of the application of phosphate fertilizers on the radioactive pollution of these waters. The activity of 226 Ra, 228 Ra, 235 U and 238 U was measured in different types of phosphate fertilizers and waters by means of γ-ray spectrometry. Surface water, water from drainage channels, shallow groundwater and deep groundwater samples were collected from the Kanovci agricultural and well field area in Eastern Slavonia, where phosphate fertilizers have been used for the past 15 years. 137 Cs was also measured in water samples. The typical phosphate fertilizer used in the Kanovci area contains 75 Bq kg -1 of 226 Ra, 9 Bq kg -1 of 228 Ra, 52 Bq kg -1 of 235 U and 1120 Bq kg -1 of 238 U. The estimated annual deposition of uranium and radium in soils of the agricultural and well field area in Kanovci is: 4.5 Bq m -2 for 226 Ra, 0.5 Bq m -2 for 228 Ra, 3.1 Bq m -2 for 235 U and 67 Bq m -2 for 238 U. The greatest concentrations of both uranium isotopes are measured in water from drainage channels with a mean value of 120 Bq m -3 for 238 U and 5.5 Bq m -3 for 235 U. The concentrations of both radium isotopes generally increase with depth of water as distinct from uranium, whose concentrations in deep groundwater are much lower. The highest concentrations of 137 Cs were measured in water from drainage channels; it was not detected in deep groundwater. The 238 U/ 226 Ra activity ratio (AR) is the highest in water from drainage channels and the Bosut River, while in deep groundwater the ratio is only 1.6. Results indicate that high uranium concentrations in surface water, shallow groundwater and water from drainage channels are caused by phosphate fertilizer application in agriculture on the Kanovci area. (author)

Uptake of CrO{sub 4}{sup 2-} ions by Fe-treated tri-calcium phosphate

Energy Technology Data Exchange (ETDEWEB)

Serrano G, J.; Ramirez S, J. L.; Bonifacio M, J.; Granados C, F.; Badillo A, V. E., E-mail: juan.serrano@inin.gob.m [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

2010-07-01

CrO{sub 4}{sup 2-} ion adsorption of Fe-treated tri-calcium phosphate was studied by batch experiments as a function of contact time, initial concentration of metal ion and temperature. Adsorption results showed that at ph 5.5 and 1.0 x 10{sup -4} M chromium concentration the adsorption capacity of Fe-treated tri-calcium phosphate for CrO{sub 4}{sup 2-} ions was 7.10 x 10{sup -3} mmol/g. Chromium adsorption data on Fe-treated tri-calcium phosphate at various initial concentration fitted the Freundlich isotherm. By temperature studies the thermodynamic parameters {Delta}H{sup 0}, {Delta}G{sup 0} and {Delta}S{sup 0} were estimated and the obtained results showed that the adsorption reaction was endothermic and spontaneous. (Author)

Radiotracer study of phosphate exchange between whey and casein micelles in cow's milk

International Nuclear Information System (INIS)

Kolar, Z.I.; Verburg, T.G.; Dijk, H.J.M. van

1998-01-01

Radiotracer method has been applied to study exchange of calcium ions between the whey calcium salts and micellar calcium phosphate (MCP). The present paper deals with a similar study pertaining to phosphate ions. 32 P-labelled Na 2 HPO 4 was used as the radiotracer for inorganic phosphates of milk. After addition of the radiotracer to skimmed-milk, samples were taken regularly for 700 hours. In the samples casein micelles were separated from whey by ultracentrifugation and finally the radiotracer quantity i.e. 32 P-concentration in the whey samples was measured using a Liquid Scintillation Counter. Compartmental analysis and modelling were used to evaluate the thus obtained time curves for radiotracer quantity in whey. This analysis revealed the presence of three phosphate compartments i.e. exchangeable phosphate entities; one being the whey phosphate. The other two are associated with the exchangeable phosphates of MCP. The mean residence times of phosphate in the latter two compartment differ considerably pointing at two distinctly different embeddings of phosphate groups in the structure of the micellar calcium phosphate of the cow's milk casein. The obtained results are in fair agreement with the mentioned model of MCP

Eutrophication decrease: Phosphate adsorption processes in presence of nitrates.

Science.gov (United States)

Boeykens, Susana P; Piol, M Natalia; Samudio Legal, Lisa; Saralegui, Andrea B; Vázquez, Cristina

2017-12-01

Eutrophication causes aquatic environment degradation as well as serious problems for different purposes of water uses. Phosphorus and nitrogen, mainly as phosphate and nitrate respectively, are considered responsible for eutrophication degradation. The focus of this work was the study of adsorption processes for decreasing phosphate and nitrate concentrations in bi-component aqueous systems. Dolomite and hydroxyapatite were selected as low-cost adsorbents. Obtained results showed that both adsorbents have high capacity for phosphate adsorption which the presence of nitrate does not modify. Hydroxyapatite proved to be the most efficient adsorbent, however, it showed a low percentage of desorption and few possibilities of reuse. Dolomite, on the other hand, allows a desorption of the adsorbed material that favours its reuse. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lar mountain phosphate ore processing using flotation approach

International Nuclear Information System (INIS)

Gharabaghi, M.; Noaparast, M.; Shafaei Tonkaboni, S. Z.

2007-01-01

The sample of Lar Mountain Phosphate deposit which is located in the southwest of Iran, was studied to upgrade its phosphate grade. The results obtained from mineralogical studies showed the presence of apatite, CaO, Al 2 O 3 , Fe 2 O 3 and SiO 2 , in which carbonate was detected as the main gangue. Two sets of direct and reverse flotation tests were performed using samples from this deposit with 10% P 2 O 5 . In phosphate flotation (direct approach), the samples were conditioned with sodium silica, oleic acid-fuel oil and Armac T-fuel oil. The direct flotation at pH=9.2 yielded a product with 23.2% of P 2 O 5 and 75.16% recovery. The reverse flotation tests were carried out at pH=5.2, with floating carbonate and pulp de-oiling, using H 2 SO 4 and wash water, and phosphate was then floated from siliceous gangue. In the second sets of the reverse approach, depressing the phosphate and floating silica with Amines in natural pH were done. However the best concentrate assay was 31.2% P 2 O 5 with a 71.12% recovery, which was obtained from reverse tests

Natural radionuclide distribution in phosphate fertilizer and superphosphate production technology

Energy Technology Data Exchange (ETDEWEB)

Lisachenko, Eh P; Ponikarova, T M; Lisitsyna, Yu Z

1987-01-01

The obtained data on the natural radionuclide distribution by phosphate fertilizer and superphosphate production process stages testify to phosphate fertilizer enrichment 2-4 times in relation to initial ore, depending in the raw material used. In this case uranium and thorium series element concentration value (in equilibrium with their decomposition products), proposed as a regulating one in phosphorus-containing fertilizers, is not achieved. However, the fact of lurichment as it is and the enrichment factor, stated in the course of the work, should be taken into account for evaluation of phosphorite new deposit raw material with higher concentrations of natural radionuclides. Natural radionuclide separation in the enrichment process and superphosphate production is not revealed.

The chemistry of high temperature phosphate solutions in relation to steam generation

International Nuclear Information System (INIS)

Broadbent, D.; Lewis, G.G.; Wetton, E.A.M.

1978-01-01

The problems associated with the use of phosphate for chemical treatment of the P.W.R. secondary circuit have prompted renewed interest in the physical chemistry of these solutions. Solubility and phase studies have been carried out at 250, 300 and 350 0 C with solutions having sodium to phosphate ratios from 1.0 to above 3.0. A solid phase of ratio about 2.8 exists in equilibrium with a wide range of saturated solution compositions at each temperature. Invariant points at which three phases are in equilibrium have been identified and at the two higher temperatures a region of liquid-liquid immiscibility occurs. Phase diagrams have been constructed for each temperature from which it is possible to predict the compositional changes occurring during the isothermal evaporation process. The corrosivity of these phosphate solutions to a range of steel alloys is being studied, the results reported in the present work, however, are confined to mild steel in the temperature and phosphate composition ranges of the phase studies. The corrosion of mild steel is generally considerably less than in sodium hydroxide solutions of equivalent concentration. The dependence of corrosion rate on sodium and phosphate concentrations in not readily explicable in terms of the solubility and phase studies and it is thought that the solubility of iron in the phosphate solutions is an important rate-determining factor since several complex compounds containing sodium, phosphorus and ferrous iron are present in the corrosion films. (author)

Evaluation of phosphate fertilizers for the immobilization of Cd in contaminated soils.

Directory of Open Access Journals (Sweden)

Yin Yan

Full Text Available A laboratory investigation was conducted to evaluate the efficiency of four phosphate fertilizers, including diammonium phosphate (DAP, potassium phosphate monobasic (MPP, calcium superphosphateon (SSP, and calcium phosphate tribasic (TCP, in terms of the toxicity and bioavailability of Cd in contaminated soils. The efficiency of immobilization was evaluated on the basis of two criteria: (a the reduction of extractable Cd concentration below the TCLP regulatory level and (b the Cd changes associated with specific operational soil fractions on the basis of sequential extraction data. Results showed that after 50 d immobilization, the extractable concentrations of Cd in DAP, MPP, SSP, and TCP treated soils decreased from 42.64 mg/kg (in the control to 23.86, 21.86, 33.89, and 35.59 mg/kg, respectively, with immobilization efficiency in the order of MPP > DAP > SSP > TCP. Results from the assessment of Cd speciation via the sequential extraction procedure revealed that the soluble exchangeable fraction of Cd in soils treated with phosphate fertilizers, especially TCP, was considerably reduced. In addition, the reduction was correspondingly related to the increase in the more stable forms of Cd, that is, the metal bound to manganese oxides and the metal bound to crystalline iron oxides. Treatment efficiency increased as the phosphate dose (according to the molar ratio of PO4/Cd increased. Immobilization was the most effective under the molar ratio of PO4/Cd at 4:1.

Evaluation of Creatine Kinase Activity and Inorganic Phosphate ...

African Journals Online (AJOL)

subjects presenting with major VOC. Keywords: Serum creatine kinase activity, Serum inorganic phosphate concentration, Sickle cell disease,. Steady state, Vaso‑occlusive crisis. Original Article. Address for correspondence: Dr. John C Aneke,. Department of Hematology,. Nnamdi Azikiwe University Teaching. Hospital ...

Evaluation of Creatine Kinase Activity and Inorganic Phosphate ...

African Journals Online (AJOL)

Background: Biochemical parameters vary in subjects with different hemoglobin phenotypes, compared with normal controls. Aim: The aim was to evaluate serum creatine kinase (CK) activity and inorganic phosphate concentrations in Nigerian adults with homozygous and heterozygous hemoglobin phenotypes. Subjects ...

Impact of Phosphate, Potassium, Yeast Extract, and Trace Metals on Chitosan and Metabolite Production by Mucor indicus.

Science.gov (United States)

Safaei, Zahra; Karimi, Keikhosro; Zamani, Akram

2016-08-30

In this study the effects of phosphate, potassium, yeast extract, and trace metals on the growth of Mucor indicus and chitosan, chitin, and metabolite production by the fungus were investigated. Maximum yield of chitosan (0.32 g/g cell wall) was obtained in a phosphate-free medium. Reversely, cell growth and ethanol formation by the fungus were positively affected in the presence of phosphate. In a phosphate-free medium, the highest chitosan content (0.42 g/g cell wall) and cell growth (0.66 g/g sugar) were obtained at 2.5 g/L of KOH. Potassium concentration had no significant effect on ethanol and glycerol yields. The presence of trace metals significantly increased the chitosan yield at an optimal phosphate and potassium concentration (0.50 g/g cell wall). By contrast, production of ethanol by the fungus was negatively affected (0.33 g/g sugars). A remarkable increase in chitin and decrease in chitosan were observed in the absence of yeast extract and concentrations lower than 2 g/L. The maximum chitosan yield of 51% cell wall was obtained at 5 g/L of yeast extract when the medium contained no phosphate, 2.5 g/L KOH, and 1 mL/L trace metal solution.

Polonium-210 in the environment around a radioactive waste disposal area and phosphate ore processing plant

Energy Technology Data Exchange (ETDEWEB)

Arthur, III, W J; Markham, O D

1984-04-01

Polonium-210 concentrations were determined for soil, vegetation and small mammal tissues collected at a solid radioactive waste disposal area, near a phosphate ore processing plant and at two rural areas in southeastern Idaho. Polonium concentrations in media sampled near the radioactive waste disposal facility were equal to or less than values from rural area samples, indicating that disposal of solid radioactive waste at the Idaho National Engineering Laboratory Site has not resulted in increased environmental levels of polonium. Concentrations of /sup 210/Po in soils, deer mice hide and carcass samples collected near the phosphate processing plant were statistically greater than the other sampling locations; however, the mean /sup 210/Po concentration in soils and small mammal tissues from sampling areas near the phosphate plant were only four and three times greater, respectively, than control values. No statistical difference was observed for /sup 210/Po concentrations in vegetation among any of the sampling locations.

Serum Calcium, Inorganic Phosphates and some Haematological ...

African Journals Online (AJOL)

Objectives: Sickle cell disease has long been associated with bone deformities and pain. Mineral salts such as calcium and inorganic phosphate are critical in bone formation and metabolism. This investigation was designed to study the serum concentration of these minerals as well as some haematological parameters in ...

Comparison of various concentrations of tricalcium phosphate nanoparticles on mechanical properties and remineralization of fissure sealants.

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Sara Tavassoli-Hojjati

2014-08-01

Full Text Available The aim of this study was to investigate the mechanical properties (flexural strength, micro-shear bond strength and remineralizing potential of fissure sealants by adding various concentrations of β-tricalcium phosphate nanoparticles.This in-vitro study consisted of five experimental groups containing prepared nano-fisssure sealants (1-5 wt.% β-TCP nanoparticles and two control groups containing a prepared and a commercial fissure sealant. Flexural/micro-shear bond strength values were measured using Zwick test machine. Cavities on sixty healthy premolar teeth were filled with the fissure sealants containing 0-5 wt.% of nano β-TCP. The samples were assessed for remineralization under scanning electron microscopy (SEM and EDAX. Kolmogorov-Smirnov test, One-way ANOVA and Tukey's Post Hoc analysis/HSD were used to analyze the data.There was no significant difference between the flexural strengths/elastic modulus of the 0-5 wt.% nano β-TCP groups (p>0.05. The average flexural strength/elastic modulus of the prepared fissure sealant group (0% was significantly higher than the commercial fissure sealant group (Clinpro (p0.05. Examining the samples under SEM showed a significant increase in thickness of the intermediate layer with increasing concentrations of β-TCP nanoparticles (p<0.05.Addition of 1-5 wt.% β-TCP nanoparticles to the fissure sealants significantly increased the remineralization potential without affecting the mechanical properties.

Improvement of Accuracy in Flow Immunosensor System by Introduction of Poly-2-[3-(methacryloylaminopropylammonio]ethyl 3-aminopropyl Phosphate

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Yusuke Fuchiwaki

2011-01-01

Full Text Available In order to improve the accuracy of immunosensor systems, poly-2-[3-(methacryloylaminopropylammonio]ethyl 3-aminopropyl phosphate (poly-3MAm3AP, which includes both phosphorylcholine and amino groups, was synthesized and applied to the preparation of antibody-immobilized beads. Acting as an antibody-immobilizing material, poly-3MAm3AP is expected to significantly lower nonspecific adsorption due to the presence of the phosphorylcholine group and recognize large numbers of analytes due to the increase in antibody-immobilizing sites. The elimination of nonspecific adsorption was compared between the formation of a blocking layer on antibody-immobilized beads and the introduction of a material to combine antibody with beads. Determination with specific and nonspecific antibodies was then investigated for the estimation of signal-to-noise ratio. Signal intensities with superior signal-to-noise ratios were obtained when poly-3MAm3AP was introduced. This may be due to the increase in antibody-immobilizing sites and the extended space for antigen-antibody interaction resulting from the electrostatic repulsion of poly-3MAm3AP. Thus, the application of poly-3MAm3AP coatings to immunoassay beads was able to improve the accuracy of flow immunosensor systems.

Seasonal fluctuations of organophosphate concentrations in precipitation and storm water runoff.

Science.gov (United States)

Regnery, Julia; Püttmann, Wilhelm

2010-02-01

To investigate seasonal fluctuations and trends of organophosphate (flame retardants, plasticizers) concentrations in rain and snow, precipitation samples were collected in 2007-2009 period at a densely populated urban sampling site and two sparsely populated rural sampling sites in middle Germany. In addition, storm water runoff was sampled from May 2008 to April 2009 at an urban storm water holding tank (SWHT). Samples were analyzed for tris(2-chloroethyl) phosphate (TCEP), tris(2-chloro-1-methylethyl) phosphate (TCPP), tris(1,3-dichloro-2-propyl) phosphate (TDCP), tris(2-butoxyethyl) phosphate (TBEP), tri-iso-butyl phosphate (TiBP), and tri-n-butyl phosphate (TnBP) by gas chromatography-mass spectrometry after solid phase extraction. Among the six analyzed organophosphates (OPs), TCPP dominated in all precipitation and SWHT water samples with maximum concentrations exceeding 1000ngL(-1). For all analytes, no seasonal trends were observed at the urban precipitation sampling site, although atmospheric photooxidation was expected to reduce particularly concentrations of non-chlorinated OPs during transport from urban to remote areas in summer months with higher global irradiation. In the SWHT a seasonal trend with decreasing concentrations in summer/autumn is evident for the non-chlorinated OPs due to in-lake degradation but not for the chlorinated OPs. Furthermore, an accumulation of OPs deposited in SWHTs was observed with concentrations often exceeding those observed in wet precipitation. Median concentrations of TCPP (880ngL(-1)), TDCP (13ngL(-1)) and TBEP (77ngL(-1)) at the SWHT were more than twice as high as median concentrations measured at the urban precipitation sampling site (403ngL(-1), 5ngL(-1), and 21ngL(-1) respectively).

A Phex mutation in a murine model of X-linked hypophosphatemia alters phosphate responsiveness of bone cells.

Science.gov (United States)

Ichikawa, Shoji; Austin, Anthony M; Gray, Amie K; Econs, Michael J

2012-02-01

Mutations in the PHEX gene cause X-linked hypophosphatemia (XLH). Hypophosphatemia in XLH results from increased circulating levels of a phosphaturic hormone, fibroblast growth factor 23 (FGF23), which inhibits renal phosphate reabsorption and 1,25-dihydroxyvitamin D (calcitriol) synthesis. The current standard therapy for XLH--high-dose phosphate and calcitriol--further increases FGF23 concentrations, suggesting that patients with XLH may have an altered response to extracellular phosphate. To test for the presence of abnormal phosphate responsiveness, we compared serum biochemistries and femoral Fgf23 mRNA expression between wild-type mice, murine models of XLH (Phex(K496X)) and hyperphosphatemic tumoral calcinosis (Galnt3(-/-)), and Galnt3/Phex double-mutant mice. Phex mutant mice had not only increased Fgf23 expression but also reduced proteolytic cleavage of intact Fgf23 protein, resulting in markedly elevated intact Fgf23 levels and consequent hypophosphatemia. In contrast, despite markedly increased Fgf23 expression, Galnt3 knockout mice had significantly high proteolytic cleavage of Fgf23 protein, leading to low intact Fgf23 concentrations and hyperphosphatemia. Galnt3/Phex double-mutant mice had an intermediate biochemical phenotype between wild-type and Phex mutant mice, including slightly elevated intact Fgf23 concentrations with milder hypophosphatemia. Despite the hypophosphatemia, double-mutant mice attempted to reduce serum phosphate back to the level of Phex mutant mice by upregulating Fgf23 expression as much as 24-fold higher than Phex mutant mice. These data suggest that Phex mutations alter the responsiveness of bone cells to extracellular phosphate concentrations and may create a lower set point for "normal" phosphate levels.

Decrease by 50% of plasma IgA tissue transglutaminase antibody concentrations within 2 months after start of gluten-free diet in children with celiac disease used as a confirming diagnostic test

DEFF Research Database (Denmark)

Lund, Flemming; Hermansen, Mette N; Pedersen, Merete F

2016-01-01

BACKGROUND: Histological examination of small bowel biopsies is normally the gold standard for the diagnosis of celiac disease (CD). The objective of this study was to investigate whether the rate of decreases in elevated plasma IgA tissue transglutaminase antibody (IgA-tTG) and/or IgG deamidated...... gliadin peptides antibody (IgG - DGP) concentrations could be used as a confirming test for CD in children on a gluten-free diet (GFD) when biopsy was omitted in the diagnostic process. METHODS: In this retrospective study we compared children (≤18 years old) with a CD-confirming biopsy (n = 16......) to children without a biopsy (n = 18). After initiation of GFD the antibody half-life (the time (T½) when the antibody concentration is 50% decreased) was determined in all children. RESULTS: Children with a biopsy (IgA-tTG, T½ = 1.9 months; IgG - DGP, T½ = 2.2 months) and children without a biopsy (Ig...

Phosphate removal from aqueous solutions using polyaniline/ Ni 0.5 Zn 0.5 Fe 2 O 4 magnetic nanocomposite

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Mohammad Hossein Tarmahi

2017-05-01

Full Text Available Background: Phosphorus is an indispensable element for the growth of animals and plants. There are several environmental problems related to phosphate; therefore, the technical and economic methods of removing phosphate are of great importance. This study evaluated the efficiency of polyaniline/ Ni0.5Zn0.5Fe2O4 magnetic nanocomposite in removing phosphate from aqueous environments. Methods: The adsorbent was characterized by several methods, including X-ray diffraction (XRD, scanning electron microscopy (SEM, vibrating sample magnetometer (VSM, and Fourier transform infrared (FT-IR spectroscopy. Then, the potential of the adsorbentto adsorb phosphate was investigated. The effects of the parameters of contact time (5-60 minutes, pH (3-9, adsorbent dosage (0.05-0.6 g, and initial phosphate concentration (2-100 mg/L on the phosphate removal yield were studied. All phosphate ion concentrations were measured using the ammonium molybdate spectrophotometric method. Results: The results showed that a time of 30 minutes, pH of 5, and adsorbent dose of 0.4 g were the optimum conditions for phosphate removal through adsorption. Increasing the initial concentration of phosphate from 2 to 100 mg/L decreased the removal efficiency from 90.3% to 32%. The experimental data was fitted well with the Freundlich isotherm model (R2 = 0.997. Conclusion: Polyaniline/Ni0.5Zn0.5Fe2O4 magnetic nanocomposite removes phosphate from aqueous solutions with a simple and environmentally benign procedure. The maximum adsorption capacity based on Langmuir isotherm (R2 = 0.931 is 85.4 mg/g. This magnetic nanocomposite is applicable in managing water resource pollution caused by phosphate ions.

Platelet concentrates stored in plasma for 72 hours at 22 degrees C prepared from buffycoats of citrate-phosphate-dextrose blood collected in a quadruple-bag saline-adenine-glucose-mannitol system

NARCIS (Netherlands)

Pietersz, R. N.; Loos, J. A.; Reesink, H. W.

1985-01-01

A method is described to prepare platelet concentrates from the buffycoat of citrate-phosphate-dextrose (CPD) blood in a closed four-bag system and to store the platelets in autologous plasma under sterile conditions. After separation of the blood into plasma, buffycoat and leukocyte- and

Study of phosphate release from Bogor botanical gardens’ sediment into pore water using diffusive gradient in thin film (DGT)

Science.gov (United States)

Tirta, A. P.; Saefumillah, A.; Foliatini

2017-04-01

Eutrophication is one of the environmental problems caused by the excessive nutrients in aquatic ecosystems. In most lakes, phosphate is a limiting nutrient for algae photosynthesis. Even though the concentration of phosphate from external loading into the water body has been reduced, eutrophication could still be occured due to internal mobilization of phosphate from the sediment pore water into the overlying water. Therefore, the released phosphate from sediments and their interaction in the pore water must be included in the monitoring of phosphate concentration in aquatic system. The released phosphate from sediment into pore water has been studied by DGT device with ferrihydrite as binding gel and N-N‧-methylenebisacrylamide as crosslinker. The results showed that DGT with 15% acrylamide; 0.1 % N-N‧-methylenebisacrylamide and ferrihydrite as binding gel was suitable for the measurement of the released phosphate from sediment into pore water. The result of the deployed DGT in oxic and anoxic conditions in seven days incubation showed the released phosphate process from the sediment into pore water was affected by incubation time and the existence of oxygen in the environment. The released phosphate from the sediment into pore water in anoxic condition has a higher value than oxic condition. The experimental results of the deployed DGT in natural sediment core at a depth of 1 to 15 cm from the surface of the water for 7 days showed that the sediment has a different phosphate mass profile based on depth. The concentration of phosphate tends to be increased with depth. The maximum CDGT of phosphate released in oxic and anoxic conditions at 7th day period of incubation are 29.23 μg/L at 14 cm depth and 30.19 μg/L at 8 cm depth, respectively.

Isotypes of Epstein-Barr Virus Antibodies in Rheumatoid Arthritis: Association with Rheumatoid Factors and Citrulline-Dependent Antibodies

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Marie Wulff Westergaard

2015-01-01

Full Text Available In order to study the humoral immune response against Epstein-Barr virus (EBV in patients with rheumatoid arthritis (RA and to compare it with the two major autoantibody types in RA, plasma samples from 77 RA patients, 28 patients with systemic lupus erythematosus (SLE, and 28 healthy controls (HCs were investigated by enzyme-linked immunosorbent assays (ELISA. Increased percentages of positives and concentrations of IgG/IgA/IgM antibodies against the latent EBV nuclear antigen-1 (EBNA-1 were observed in RA patients compared to SLE patients and HCs. Increased concentrations and percentages of positives of IgG/IgA/IgM against the early lytic EBV antigen diffuse (EAD were also found in RA patients compared to HCs but were highest in SLE patients. Furthermore, associations between the elevated EBNA-1 IgA and EBNA-1 IgM levels and the presence of IgM and IgA rheumatoid factors (RFs and anti-citrullinated protein antibodies (ACPAs, IgG and between elevated IgA concentrations against EAD and the presence of RFs and ACPAs in RA patients were found. Thus, RA patients had elevated antibodies of all isotypes characteristic of latent EBV infection (whereas SLE patients had elevated antibodies characteristic of lytic EBV infection. Notably, for IgM and IgA (but not IgG, these were associated with the presence of characteristic RA autoantibodies.

Effects of phosphate environments on turbine materials: preliminary results

International Nuclear Information System (INIS)

Chen, M.C.; Shalvoy, R.S.; Gould, G.C.

1985-01-01

Stress corrosion cracking (SCC) is a serious hazard to large steam turbines. In many cases, this cracking is thought caused by concentrated deposits of caustics or chlorides, formed from the steam by concentrating mechanisms. To minimize the likelihood of forming these corrosive deposits, turbine manufacturers recommend that the levels of contaminants in the steam be maintained at low levels. The steam purity needed to prevent the formation of corrosive deposits is at present uncertain. As an aid in judging the steam purity needed to avoid corrosive deposits, the General Electric Company surveyed the utility industry to determine current feedwater practices, the levels of steam purity attained, and the nature of the corrosion problems encountered. One hypothesis to explain the lower corrosivity of steam from drum boilers concerns the sodium phosphate to compounds commonly added to drum boiler water for pH control. To test this hypothesis, the present program was undertaken to study the effect of sodium phosphate on the corrosivity of the two most common corrosive turbine deposits, sodium chloride and sodium hydroxide. Four turbine materials - a rotor steel, a disc steel, and two turbine blade steels - were chosen for this study. The results from the first half of a two-year project are described. So far the corrosivity of the deposits without phosphate has been determined. Work to determine the corrosivity of deposits with phosphate is presently under way and only the electrochemical test results are discussed

Potential radiological impact of the phosphate industry on wildlife

International Nuclear Information System (INIS)

Vandenhove, Hildegarde; Vives i Batlle, Jordi; Sweeck, Lieve

2015-01-01

The activities of the phosphate industry may lead to enhanced levels of naturally occurring radioactivity in terrestrial and aquatic ecosystems. We performed a preliminary environmental risk assessment (ERA) of environmental contamination resulting from the activities of 5 phosphate fertiliser plants (located in Belgium, Spain, Syria, Egypt, Brazil), a phosphate-mine and a phosphate-export platform in a harbour (both located in Syria). These sites were selected because of the availability of information on concentrations of naturally occurring radionuclides in the surrounding environments. Assessments were generally performed considering highest environmental concentrations reported in the studies. The ERICA Tool, operating in a Tier 2 assessment mode, was used to predict radiation dose rates and associated risk to the selected reference organisms using the ERICA default parameter setting. Reference organisms were those assigned as default by the ERICA Tool. Potential impact is expressed as a best estimate risk quotient (RQ) based on a radiation screening value of 10 μGy h −1 . If RQ ≤ 1, the environment is considered unlikely to be at risk and further radiological assessment is not deemed necessary. Except for one of the cases assessed, the best estimate RQ exceeded 1 for at least one of the reference organisms. Internal exposure covered for 90–100 % of the total dose. 226 Ra or 210 Po were generally the highest contributors to the dose. The aquatic ecosystems in the vicinity of the phosphate fertiliser plants in Tessenderlo (Belgium), Huelva (Spain), Goiás (Brazil) and the terrestrial environment around the phosphate mine in Palmyra (Syria) are the ecosystems predicted to be potentially most at risk. - Highlights: • The adjusted highlights Environmental radionuclide enrichment from P-industry warrants risk assessment. • 226 Ra and 210 Po are the most dose contributing radionuclides. • The total dose rate is strongly driven by the internal

Minimalistic Liquid-Assisted Route to Highly Crystalline α-Zirconium Phosphate.

Science.gov (United States)

Cheng, Yu; Wang, Xiaodong Tony; Jaenicke, Stephan; Chuah, Gaik-Khuan

2017-08-24

Zirconium phosphates have potential applications in areas of ion exchange, catalysis, photochemistry, and biotechnology. However, synthesis methodologies to form crystalline α-zirconium phosphate (Zr(HPO 4 ) 2 ⋅H 2 O) typically involve the use of excess phosphoric acid, addition of HF or oxalic acid and long reflux times or hydrothermal conditions. A minimalistic sustainable route to its synthesis has been developed by using only zirconium oxychloride and concentrated phosphoric acid to form highly crystalline α-zirconium phosphate within hours. The morphology can be changed from platelets to rod-shaped particles by fluoride addition. By varying the temperature and time, α-zirconium phosphate with particle sizes from nanometers to microns can be obtained. Key features of this minimal solvent synthesis are the excellent yields obtained with high atom economy under mild conditions and ease of scalability. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Co-sequestration of Zn(II) and phosphate by γ-Al{sub 2}O{sub 3}: From macroscopic to microscopic investigation

Energy Technology Data Exchange (ETDEWEB)

Ren, Xuemei [School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206 (China); Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, 230031, Hefei (China); Tan, Xiaoli [Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, 230031, Hefei (China); Hayat, Tasawar [Department of Mathematics, Quaid-I-Azam University, Islamabad 44000 (Pakistan); NAAM Research Group, Faculty of Science, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Alsaedi, Ahmed [NAAM Research Group, Faculty of Science, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Wang, Xiangke, E-mail: xkwang@ipp.ac.cn [School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206 (China); NAAM Research Group, Faculty of Science, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions (China)

2015-10-30

Highlights: • How the Zn and phosphate behave in each other’s presence is elucidated. • Surface speciation of Zn(II) is affected by the presence of phosphate. • Combining macroscopic study with EXAFS can determine the Zn(II) surface speciation. • The enhanced Zn(II) sorption is mainly due to ternary surface complexation at 0.19 mmol P/L and pH 6.5. • Phosphate ions prevent the formation of an Zn–Al LDH phase at pH 8.0. - Abstract: Little information is available concerning co-sorbing oxyanion and metal contaminants in the environment, yet in most metal-contaminated areas, co-contamination by phosphate is common. In this study, the mutual effects of phosphate and Zn(II) on their interaction with γ-Al{sub 2}O{sub 3} are investigated by batch experiments and X-ray absorption fine structure spectroscopy (XAFS) technique. The results show that the co-sorption of phosphate on γ-Al{sub 2}O{sub 3} modifies both the extent of Zn(II) sorption and the local atomic structures of sorbed Zn(II) ions. Multiple mechanisms are involved in Zn(II) retention in the presence of phosphate, including electrostatic interaction, binary and ternary surface complexation, and the formation of Zn(II)-phosphate polynuclear complexes. At pH 6.5, type III ternary surface complexation occurs concurrently with binary Zn-alumina surface complexation at low phosphate concentrations, whereas the formation of type III ternary surface complexes is promoted as the phosphate concentration increases. With further increasing phosphate concentration, Zn(II)-phosphate polynuclear complexes are formed. At pH 8.0, Zn dominantly forms type III ternary surface complexes in the presence of phosphate. The results of this study indicate the variability of Zn complexation on oxide surface and the importance of combining macroscopic observations with XAFS capable of determining metal complex formation mechanism for ternary system.

A Review on New Technological Progress for Beneficiation of Refractory Phosphate Ore in China

Science.gov (United States)

Dong, Xu; Siqing, Liu; Yanqing, Yao; Hailin, Liu; Yi, Pei

2017-05-01

The world is rich in phosphate resources, but the vast majority of the resources are of middle and low grade ores, and it is difficult to obtain high grade concentrate at a high recovery by using traditional separation methods. In this paper, the distribution and flotation processes of typical phosphate ores in China are introduced. Considering the current situation in phosphate ore beneficiation both home and abroad, the new trend of processing technology and reagents in China are summarized. Flotation is still regarded as the main processing method in phosphate ore beneficiation for a certain time in near future.

Some peculiarities of the relationship between uranium and phosphate of nodular phosphorites of the Russian Platform

Energy Technology Data Exchange (ETDEWEB)

Kozlov, A A [Vsesoyuznyj Nauchno-Issledovatel' skij Inst. Yadernoj Geofiziki i Geokhimii, Moscow (USSR)

1976-02-01

In nodular phosphorites of the Cenomanian stage of the central regions of the Russian platform the uranium content of phosphate ranges within 20 to 50x10/sup -4/%. The maximum concentrations of uranium are found in amorphous phosphates, the richest in humic colloid. Uranium found in the bone phosphate of fossil reptiles is uniformly distributed throughout the bone tissue area, its content amounting to 30 to 40x10/sup -4/%. As bone phosphate reaches its holocrystalline modification, the uranium compounds are substituted and the uranium concentration decreases to 0.2x10/sup -4/%, i.e. it becomes 200 times lower. The most intensive sorption of uranium by phosphate occurs under the reducing conditions of diagenesis which is characterized by the most comprehensive combination of uranium-sorption factors: the existence of various uranium compounds in solution, isomorphic substitutions of all kinds, adsorption of uranium compounds and organic matter on the surfaces of submicron crystalline phosphate compounds. A decrease in the intensity of sorption factors leads to a decrease in the uranium content of phosphate. Under the oxidative conditions prevailed during the formation of Khoperian silicophosphorites, uranium has been sorbed by the phosphate only in negligible amounts (0.1x10/sup -4/%) due to the lack of organic colloids and uranium compounds capable of isomorphic substitution.

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

Removal of lead and phosphate ions from aqueous solutions by organo-smectite.

Science.gov (United States)

Bajda, Tomasz; Szala, Barbara; Solecka, Urszula

2015-01-01

Smectite has been modified using hexadecyltrimethyl ammonium bromide in an amount of double cationic exchange capacity. This alteration makes it possible to use organo-smectite as a sorbent to remove anionic forms. The experiment consisted of the interchangeable sorption of phosphate(V) and lead(II) by organo-smectite. Research was carried out with varying pH (2-5) and various concentrations (0.1-5 mmol/L). Organo-smectite with previously adsorbed lead ions removed more phosphate than the untreated organo-smectite. Experimental data show that lead is more likely to absorb on the organo-smectite than on the organo-smectite with previously adsorbed phosphate ions. It follows that the most effective use of the organo-smectite is through the sorption of first - Pb cations and then PO4 anions. With an increasing concentration of Pb(II) or P(V), the sorption efficiency increases. The maximum sorption efficiency of lead and phosphate ions is observed at pH 5. This enables the removal of harmful lead and phosphorus compounds from waste water and immobilizes them on the sorbent's surface. The alternating reactions of lead and phosphorus ions result in the crystallization of brompyromorphite Pb5(PO4)3Br.

Uranium extraction from ores with salicylic acid; I - uranium extraction from input phosphate ore of Abu Zaabal phosphate plant, Egypt

International Nuclear Information System (INIS)

Hussein, E.M.

1997-01-01

Salicylic acid has been tested (for environmental importance) to extract U from input phosphate ore of Abu-Zaabal phosphate plant, Egypt prior to its processing for production of phosphatic fertilizers. Uranyl ion forms with this acid three stable complexes; namely [UO 2 Sal] degree, [U O 2 SaL 2 ] 2- and UO 2 SaL-3] 4- depending on the total uranyl and salicylic acid concentrations and their ratios. Study of relevant extraction factors revealed however that, the extraction process is controlled by the amount of salicylic acid used, alcohol/aqueous ratio, solid/liquid ratio and time of agitation. The obtained results showed that uranium is selectively leached by the application of such a leaching reagent. In order to recover U from the obtained pregnant leach liquor, the latter is adjusted by ammonia to PH 5-6.5, where the crystalline pp t of N H 4 [UO 2 SaL 3 ] 4 H 2 O has formed. This precipitation has been carried out after concentrating the obtained pregnant leach liquor by its recycle for U extraction from new ore batches. The precipitated ammonium uranyl tri salicylate is calcined at 500 degree C for obtaining pure orange yellow trioxide (UO 3 ) powder. On the basis of one ton ore treatment, an economic flowsheet for U recover y from the study ore material has been suggested

Nanofluidic Pre-Concentration Devices for Enhancing the Detection Sensitivity and Selectivity of Biomarkers for Human Performance Monitoring

Science.gov (United States)

2016-10-17

antibody by glutaraldehyde coupling, for enabling the selective catalysis of α-naphthyl phosphate (NPP) to the electroactive α-naphthol (NP) product , as...solution at 4 °C overnight. The dialysis product , PSA antibody-ALP conjugate, was then transferred to an Eppendorf tube and mixed with an equal...volume of glycerin and 1% BSA, for storage at 0 °C, prior to the experiments. Cortisol, Triamcinolone, Estradiol, Testosterone and Progesterone were

Urinary metabolites of phosphate flame retardants in workers occupied with e-waste recycling and incineration.

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Yan, Xiao; Zheng, Xiaobo; Wang, Meihuan; Zheng, Jing; Xu, Rongfa; Zhuang, Xi; Lin, Ying; Ren, Mingzhong

2018-06-01

Urinary metabolites of phosphate flame retardants (PFRs) were determined in workers from an electronic waste (e-waste) recycling site and an incineration plant, in order to assess the PFR exposure risks of workers occupied with e-waste recycling and incineration. Bis(2-chloroethyl) phosphate (BCEP), bis(1,3-dichloro-2-propyl) phosphate (BDCIPP), and diphenyl phosphate (DPHP) were the most frequently detected chemicals (82-93%). The median concentrations of BCEP, BDCIPP, and DPHP were 1.77, 0.23, and 0.70 ng/mL, and 1.44, 0.22, and 0.11 ng/mL in samples from the e-waste site and the incineration plant, respectively. Dibutyl phosphate (DBP) was detected in all samples from the incineration plant, with a median level of 0.30 ng/mL. The concentrations of BDCIPP (r = -0.31, p waste site. Negative and significant correlations were also observed between the concentrations of BCEP (r = -0.42, p incineration plant. No gender differences were observed in levels of PFR metabolites in urine samples (p > 0.05). Concentrations of BDCIPP in female were significantly correlated with occupational exposure time (r = -0.507, p  0.05). Overall, the workers with occupational exposure to PFRs had different profiles of urinary PFR metabolites. The age, occupational exposure time, and gender seemed not to be main factors mediating the exposure to PFRs for workers occupied with e-waste recycling and incineration. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Ability of Watercress (Nasturtiumofficinale and Pennyroyal (Menthapulegium in Clean up Excess Nitrate and Phosphate of Water

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Z. Ahmadpoor

2016-02-01

Full Text Available Introduction: There is necessary to clean up the nitrate and phosphate from surface waters before effluence of them to environment and eutrophication formation because of water health importance and considering to nitrate and phosphate consequences. Nitrate and ammonium as the - forms of inorganic and nitrogen have been subjected to the center of issues related to environment pollutants and water resources in a long time. The nitrate is more important than other inorganic nitrogen forms such as ammonium because of various reasons such as high dynamics and causing diseases such as some of digestion system and lymph nodes cancers in adults and methemoglobinemia in infants. Therefore the maximum concentration of this ion in drinking water has been determined as 45 mg.Lit-1 by WHO. Regarding the importance of the water health and the complications due to existence of some compounds such as nitrate and phosphate, in this experiment, the possibility of elimination or decreasing excess nitrate and phosphate from water in hydroponic conditions using of two watercress and pennyroyal plants was evaluated. Watercress(Nasturtiumofficinale and pennyroyal (Menthapulegiumwere selected because of some properties such as adaptability with the most climates of Iranamd less requirements care. Materials and Methods: Two RCD factorial experiments were carried out to evaluate the ability of watercress and pennyroyal to biosorption of nitrate and phosphate from polluted water in hydroponic conditions. First factor was plant species including watercress and pennyroyal. Second factor included nitrate (50, 100, 150 Mg/L and phosphate (5, 10, 15 Mg/L in first and second experiment respectively.The final concentrations of nitrate and phosphate in water was measured using spectrophotometer in wavelength of 410 nm and 690 nm by sulphatebrucine and chloride methods , respectively, which are mentioned in Standard Methods for the Examination of Water and Wastewater. At the end

Removal of Phosphate from Synthetic Aqueous Solution by Adsorption with Dolomite from Padalarang

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Fadjari Lucia Nugroho

2014-12-01

Full Text Available The presence of phosphate in wastewaters can cause eutrophication of surface water bodies leading to algal-blooming in the aquatic environment and degradation of water quality. Phosphate removal from wastewaters by conventional biological treatment removes only 10-30% of the phosphate, whilst chemical treatment using precipitants such as calcium or iron salts, although effective, is expensive and produces water-rich sludge which must be further treated. Hence, phosphate removal by adsorption in the form of Ca -phosphate has been proposed as an alternative to the more traditional methods. This study investigated the feasibility of using dolomite–a common sedimentary rock–from Padalarang, West Java, Indonesia as the adsorbent for the removal of phosphate from synthetic aqueous solution. Chemical analysis revealed that the Padalarang dolomite contains 33.6-36.2% CaO. Batch experiments at room temperature indicated that optimum removal of phosphate was achieved at pH 9. At 25°C , where increasing concentrations of phosphate (10–100 mg/L increased phosphate adsorption (2.15-31.3 mg/g by the dolomite. The adsorption of phosphate could be described by the Langmuir isotherm model, with constants Qm= 476.19 mg/g, K L= 0,00106 L/mg and equilibrium parameter (R L: 0.904 – 0.989. Phosphate adsorption by dolomite not only permits its removal but also its potential recovery for reuse.

Partial characterization of the cross-reacting determinant, a carbohydrate epitope shared by decay accelerating factor and the variant surface glycoprotein of the African Trypanosoma brucei.

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Shak, S; Davitz, M A; Wolinsky, M L; Nussenzweig, V; Turner, M J; Gurnett, A

1988-03-15

The variant surface glycoprotein (VSG) of the African trypanosome is anchored in the cell membrane by a complex glycan attached to phosphatidylinositol. The carboxyl terminal portion of VSG contains a cryptic carbohydrate epitope, the cross-reacting determinant (CRD), that is revealed only after removal of the diacylglycerol by phosphatidylinositol-specific phospholipase C (PIPLC) or VSG lipase. Recently, we have shown that after hydrolysis by PIPLC, decay-accelerating factor (DAF)--a mammalian phosphatidylinositol-anchored protein--also contains the CRD epitope. Using a two site immunoradiometric assay in which the capturing antibody is a monoclonal antibody to DAF and the revealing antibody is anti-CRD, we now show that sugar phosphates significantly inhibited the binding of anti-CRD antibody to DAF released by PIPLC. DL-myo-inositol 1,2-cyclic phosphate was the most potent inhibitor of binding (IC50 less than 10(-8) M). Other sugar phosphates, such as alpha-D-glucose-1-phosphate, which also possess adjacent hydroxyl and phosphate moieties in cis also inhibited binding at low concentrations (IC50 = 10(-5) to 10(-4) M). In contrast, sugar phosphates which do not possess adjacent hydroxyl and phosphate moieties in cis and simple sugars weakly inhibited binding (IC50 greater than 10(-3) M). These results suggest that myo-inositol 1,2-cyclic phosphate contributes significantly to the epitope recognized by the anti-CRD antibody and is consistent with analysis of the carboxyl terminus of VSG, which also suggested the presence of the cyclic inositol phosphate. In light of the recent findings that human serum contains a glycan-phosphatidyl-inositol-specific phospholipase D, which converts DAF from a hydrophobic to a hydrophilic form lacking the CRD, the observation that the phosphate is crucial for expression of the epitope may be relevant in understanding the origin of CRD-negative DAF in urine and plasma.

Removal of phosphate from greenhouse wastewater using hydrated lime.

Science.gov (United States)

Dunets, C Siobhan; Zheng, Youbin

2014-01-01

Phosphate (P) contamination in nutrient-laden wastewater is currently a major topic of discussion in the North American greenhouse industry. Precipitation of P as calcium phosphate minerals using hydrated lime could provide a simple, inexpensive method for retrieval. A combination of batch experiments and chemical equilibrium modelling was used to confirm the viability of this P removal method and determine lime addition rates and pH requirements for greenhouse wastewater of varying nutrient compositions. Lime: P ratio (molar ratio of CaMg(OH)₄: PO₄‒P) provided a consistent parameter for estimating lime addition requirements regardless of initial P concentration, with a ratio of 1.5 providing around 99% removal of dissolved P. Optimal P removal occurred when lime addition increased the pH from 8.6 to 9.0, suggesting that pH monitoring during the P removal process could provide a simple method for ensuring consistent adherence to P removal standards. A Visual MINTEQ model, validated using experimental data, provided a means of predicting lime addition and pH requirements as influenced by changes in other parameters of the lime-wastewater system (e.g. calcium concentration, temperature, and initial wastewater pH). Hydrated lime addition did not contribute to the removal of macronutrient elements such as nitrate and ammonium, but did decrease the concentration of some micronutrients. This study provides basic guidance for greenhouse operators to use hydrated lime for phosphate removal from greenhouse wastewater.

Comparison of serum and salivary antibodies in children vaccinated with oral live or parenteral inactivated poliovirus vaccines of different antigen concentrations.

Science.gov (United States)

Zaman, S; Carlsson, B; Jalil, F; Mellander, L; Van Wezel, A L; Böttiger, M; Hanson, L A

1991-12-01

A new antigen-rich inactivated poliovirus vaccine (IPV) in ordinary (IPV1), double (IPV2) and quadruple (IPV4) antigen concentrations was given in 2 doses to 6 and 18 week old Pakistani infants. The immune responses to poliovirus types 1 and 3 were compared to those in infants given three doses of oral poliovirus vaccine (OPV) at 6, 12 and 18 weeks of age. Enzyme-linked immunosorbent assay, ELISA, was used to estimate IgG and IgA in serum and secretory IgA (SIgA) in saliva. Two to three years later, a follow-up of the serum antibody response was carried out in the same infants using a microneutralization test. Serum IgG antibody responses to poliovirus type 1 antigen after two doses of IPV1, IPV2 and IPV4 were not significantly higher than the response after three doses of OPV at 21 weeks of age (p greater than 0.05). The serum IgG responses to poliovirus type 3 were similar to those against type 1 in all the groups. Mean neutralizing antibody titres to poliovirus type 1 was significantly higher in the IPV2 group than the rest of the groups (p less than 0.01). For type 3, these titres were highest but not significantly, in the IPV4 group (p greater than 0.05). This study shows that two doses of a new antigen-rich IPV can give similar immediate serum antibody responses as OPV but higher late responses. SIgA antibodies in saliva were more efficiently induced by OPV after three doses than after 2 doses of IPV (p less than 0.05).

Maternal plasma pyridoxal-5'-phosphate concentrations and risk of isolated oral clefts in the Philippines.

Science.gov (United States)

Tamura, Tsunenobu; Munger, Ronald G; Nepomuceno, Buena; Corcoran, Christopher; Cembrano, Joselito; Solon, Florentino

2007-04-01

We report that inadequate vitamin B-6 status of Filipino mothers, assessed by erythrocyte aspartate aminotransferase activity coefficient (EAST-AC), is associated with an increased risk for isolated cleft lip with or without cleft palate (CL/P) in their children. Its association with the status assessed by plasma pyridoxal-5'-phosphate (PLP) concentrations is unknown. In a case-control study in the Philippines including 46 cases (mothers of a child with CL/P) and 392 controls (mothers of an unaffected child), we evaluated the association between the risk for CL/P and maternal vitamin B-6 status assessed by PLP and EAST-AC. The ORs of CL/P were estimated by classifying mothers by PLP (>30, 20-30, and values, compared to those with adequate status by both values. Inadequate vitamin B-6 status assessed by maternal PLP and EAST-AC values independently and both combined was associated with an increased risk for CL/P. The association was highest when both values were considered, suggesting that the measurement of both PLP and EAST-AC provides better assessment of vitamin B-6 status than either measurement alone.

Structural features of silver-doped phosphate glasses in zone of femtosecond laser-induced modification

Science.gov (United States)

Vasileva, A. A.; Nazarov, I. A.; Olshin, P. K.; Povolotskiy, A. V.; Sokolov, I. A.; Manshina, A. A.

2015-10-01

Femtosecond (fs) laser writing of two-dimensional microstructures (waveguides) is demonstrated in bulk phosphate glasses doped with silver ions. Silver-content phosphate and silver-content niobium-phosphate glasses with high concentration of silver oxide 55 mol% were used as samples for fs laser writing. The chemical network structure of the synthesized samples is analyzed through Raman spectroscopy and was found to be strongly sensitive to Nb incorporation. It was found that the direct laser writing process enables not only reorganization of glass network, but also formation of color centers and silver nanoparticles that are revealed in appearance of luminescence signal and plasmon absorption. The process of NPs' formation is more efficient for Nb-phosphate glass, while color centers are preferably formed in phosphate glass.

Economical and environmental impact of using of Nuba Mountain Rock Phosphate that contain uranium as a fertilizer without any treatment

International Nuclear Information System (INIS)

Hassan, Abdelrahman Khidir

1994-01-01

This study investigates the possible use of ground rock phosphate in Nuba Mountain for fertilization of arable land. Geological and chemical component of untreated ground rock phosphate has been compared with other ground rock phosphate from different geographical regions worldwide. The data show that economic exploitation of this rock phosphate as fertilizer is not feasible because of low solubility and low phosphorus content (12% on average). In addition, the high concentration of some elements in the rock phosphate could adversely affect the growth of the plant when it is applied on the soil by changing the chemical composition of the soil.As regards the environmental impact that could be result from the use of the rock phosphate as fertilizer is that it will unnecessarily increase the concentration of uranium which amount to 0.3% in the soil. The study recommends the use of this rock phosphate as a raw material for production of phosphoric acid and extraction of uranium and some elements as a bi-product of phosphate industry.(Author)

Hydrogen production by electrolysis of a phosphate solution on a stainless steel cathode

International Nuclear Information System (INIS)

De Silva Munoz, L.; Bergel, A.; Basseguy, R.; Feron, D.

2010-01-01

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. (authors)

Biogeochemistry of uranium in plants associated to phosphatic rocks in the coastal region of Syria

International Nuclear Information System (INIS)

Jubeli, Y.; Al-Oudat, M.; Al-Rayes, A.; El-Sharabi, N.A.

2000-07-01

Investigation studies in general, demonstrate that background levels of U in plant ash are less than 2 ppm and plant materials which contain more in excess of this amount are indicative either of local uranium mineralization, or the presence of high background levels of uranium in the substrate. Uranium concentrations in different plant parts grown on decomposite phosphate rocks in the mountain coast region of Syria was investigated. Mean uranium concentrations in the soil ranged between 0.44 - 3.91 ppm in the reference area and 22 - 92 ppm in the area of outcrop in phosphate rocks. The results showed that low-order plant forms (Fuaria, Lycopodium, and Pteridium) readily accumulate uranium, whereas high-order forms accumulate uranium in certain parts only. The greatest amount of uranium in flowering parts is concentrated in the plant roots, followed by leaves, twigs and fruits. In addition, results showed that there is a good correlation between uranium in soil and uranium in plant roots. the study demonstrate that Galium Canum could be considered as a good uranium indicator plant for two reason: It was distributed on decomposite phosphate rocks only, and the high concentration of uranium in aerial part similar to the concentration in soil (89.9 ppm). Lagurus Ovatus may be considered as uranium indicator plant, because it was highly dense on the outcrop phosphate rocks, and has a high uranium concentration in its roots (up to 93 ppm) and aerial parts (up to 33 ppm) compared to concentrations in roots and aerial parts in the reference area (10.2 and 0.37 ppm) respectively. (Author)

Chemical activation of gasification carbon residue for phosphate removal

Science.gov (United States)

Kilpimaa, Sari; Runtti, Hanna; Lassi, Ulla; Kuokkanen, Toivo

2012-05-01

Recycling of waste materials provides an economical and environmentally significant method to reduce the amount of waste. Bioash formed in the gasification process possesses a notable amount of unburned carbon and therefore it can be called a carbon residue. After chemical activation carbon residue could be use to replace activated carbon for example in wastewater purification processes. The effect of chemical activation process variables such as chemical agents and contact time in the chemical activation process were investigated. This study also explored the effectiveness of the chemically activated carbon residue for the removal of phosphate from an aqueous solution. The experimental adsorption study was performed in a batch reactor and the influence of adsorption time, initial phosphate concentration and pH was studied. Due to the carbon residue's low cost and high adsorption capacity, this type of waste has the potential to be utilised for the cost-effective removal of phosphate from wastewaters. Potential adsorbents could be prepared from these carbonaceous by-products and used as an adsorbent for phosphate removal.

Prediction of the Setting Properties of Calcium Phosphate Bone Cement

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Seyed Mahmud Rabiee

2012-01-01

Full Text Available Setting properties of bone substitutes are improved using an injectable system. The injectable bone graft substitutes can be molded to the shape of the bone cavity and set in situ when injected. Such system is useful for surgical operation. The powder part of the injectable bone cement is included of β-tricalcium phosphate, calcium carbonate, and dicalcium phosphate and the liquid part contains poly ethylene glycol solution with different concentrations. In this way, prediction of the mechanical properties, setting times, and injectability helps to optimize the calcium phosphate bone cement properties. The objective of this study is development of three different adaptive neurofuzzy inference systems (ANFISs for estimation of compression strength, setting time, and injectability using the data generated based on experimental observations. The input parameters of models are polyethylene glycol percent and liquid/powder ratio. Comparison of the predicted values and measured data indicates that the ANFIS model has an acceptable performance to the estimation of calcium phosphate bone cement properties.

Phosphate geochemistry, mineralization processes, and Thioploca distribution in shelf sediments off central Chile

DEFF Research Database (Denmark)

Holmkvist, Lars; Arning, Esther T.; Küster-Heins, Kathrin

2010-01-01

Sediments underlying the major costal upwelling systems of the world oceans are hot-spots of modern formation of hydroxyapatites, often associated with benthic communities of large, nitrate-accumulating sulfur bacteria. We studied the association between phosphate release, organic phosphorus...... to the pore water reached 100-300 μM peak concentrations within the uppermost 0-5 cm and phosphate was lost to the overlying anoxic water column. The large phosphate release was not directly related to the presence of Thioploca but was rather the result of a high deposition and mineralization rate of fresh...

Cell-free synthesis of functional antibody fragments to provide a structural basis for antibody-antigen interaction.

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Takayoshi Matsuda

Full Text Available Growing numbers of therapeutic antibodies offer excellent treatment strategies for many diseases. Elucidation of the interaction between a potential therapeutic antibody and its target protein by structural analysis reveals the mechanism of action and offers useful information for developing rational antibody designs for improved affinity. Here, we developed a rapid, high-yield cell-free system using dialysis mode to synthesize antibody fragments for the structural analysis of antibody-antigen complexes. Optimal synthesis conditions of fragments (Fv and Fab of the anti-EGFR antibody 059-152 were rapidly determined in a day by using a 30-μl-scale unit. The concentration of supplemented disulfide isomerase, DsbC, was critical to obtaining soluble antibody fragments. The optimal conditions were directly applicable to a 9-ml-scale reaction, with linear scalable yields of more than 1 mg/ml. Analyses of purified 059-152-Fv and Fab showed that the cell-free synthesized antibody fragments were disulfide-bridged, with antigen binding activity comparable to that of clinical antibodies. Examination of the crystal structure of cell-free synthesized 059-152-Fv in complex with the extracellular domain of human EGFR revealed that the epitope of 059-152-Fv broadly covers the EGF binding surface on domain III, including residues that formed critical hydrogen bonds with EGF (Asp355EGFR, Gln384EGFR, H409EGFR, and Lys465EGFR, so that the antibody inhibited EGFR activation. We further demonstrated the application of the cell-free system to site-specific integration of non-natural amino acids for antibody engineering, which would expand the availability of therapeutic antibodies based on structural information and rational design. This cell-free system could be an ideal antibody-fragment production platform for functional and structural analysis of potential therapeutic antibodies and for engineered antibody development.

Metabolomics reveals distinct, antibody-independent, molecular signatures of MS, AQP4-antibody and MOG-antibody disease.

Science.gov (United States)

Jurynczyk, Maciej; Probert, Fay; Yeo, Tianrong; Tackley, George; Claridge, Tim D W; Cavey, Ana; Woodhall, Mark R; Arora, Siddharth; Winkler, Torsten; Schiffer, Eric; Vincent, Angela; DeLuca, Gabriele; Sibson, Nicola R; Isabel Leite, M; Waters, Patrick; Anthony, Daniel C; Palace, Jacqueline

2017-12-06

The overlapping clinical features of relapsing remitting multiple sclerosis (RRMS), aquaporin-4 (AQP4)-antibody (Ab) neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein (MOG)-Ab disease mean that detection of disease specific serum antibodies is the gold standard in diagnostics. However, antibody levels are not prognostic and may become undetectable after treatment or during remission. Therefore, there is still a need to discover antibody-independent biomarkers. We sought to discover whether plasma metabolic profiling could provide biomarkers of these three diseases and explore if the metabolic differences are independent of antibody titre. Plasma samples from 108 patients (34 RRMS, 54 AQP4-Ab NMOSD, and 20 MOG-Ab disease) were analysed by nuclear magnetic resonance spectroscopy followed by lipoprotein profiling. Orthogonal partial-least squares discriminatory analysis (OPLS-DA) was used to identify significant differences in the plasma metabolite concentrations and produce models (mathematical algorithms) capable of identifying these diseases. In all instances, the models were highly discriminatory, with a distinct metabolite pattern identified for each disease. In addition, OPLS-DA identified AQP4-Ab NMOSD patient samples with low/undetectable antibody levels with an accuracy of 92%. The AQP4-Ab NMOSD metabolic profile was characterised by decreased levels of scyllo-inositol and small high density lipoprotein particles along with an increase in large low density lipoprotein particles relative to both RRMS and MOG-Ab disease. RRMS plasma exhibited increased histidine and glucose, along with decreased lactate, alanine, and large high density lipoproteins while MOG-Ab disease plasma was defined by increases in formate and leucine coupled with decreased myo-inositol. Despite overlap in clinical measures in these three diseases, the distinct plasma metabolic patterns support their distinct serological profiles and confirm that these

Correlation of pharmacodynamic activity, pharmacokinetics, and anti-product antibody responses to anti-IL-21R antibody therapeutics following IV administration to cynomolgus monkeys

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Spaulding Vikki

2010-04-01

Full Text Available Abstract Background Anti-IL-21R antibodies are potential therapeutics for the treatment of autoimmune diseases. This study evaluated correlations between the pharmacodynamic (PD activity, pharmacokinetics, and anti-product antibody responses of human anti-IL-21R antibodies Ab-01 and Ab-02 following IV administration to cynomolgus monkeys. Methods The PD assay was based on the ability of recombinant human IL-21 (rhuIL-21 to induce expression of the IL-2RA gene in cynomolgus monkey whole blood samples ex vivo. Monkeys screened for responsiveness to rhuIL-21 stimulation using the PD assay, were given a single 10 mg/kg IV dosage of Ab-01, Ab-02, or a control antibody (3/group, and blood samples were evaluated for PD activity (inhibition of IL-2RA expression for up to 148 days. Anti-IL-21R antibody concentrations and anti-product antibody responses were measured in serum using immunoassays and flow cytometry. Results Following IV administration of Ab-01 and Ab-02 to cynomolgus monkeys, PD activity was observed as early as 5 minutes (first time point sampled. This PD activity had good correlation with the serum concentrations and anti-product antibody responses throughout the study. The mean terminal half-life (t1/2 was ~10.6 and 2.3 days for Ab-01 and Ab-02, respectively. PD activity was lost at ~5-13 weeks for Ab-01 and at ~2 weeks for Ab-02, when serum concentrations were relatively low. The estimated minimum concentrations needed to maintain PD activity were ~4-6 nM for Ab-01 and ~2.5 nM for Ab-02, and were consistent with the respective KD values for binding to human IL-21R. For Ab-01, there was noticeable inter-animal variability in t1/2 values (~6-14 days and the resulting PD profiles, which correlated with the onset of anti-product antibody formation. While all three Ab-01-dosed animals were positive for anti-Ab-01 antibodies, only one monkey (with the shortest t1/2 and the earliest loss of PD activity had evidence of neutralizing anti-Ab-01

Gadolinium-hydrogen ion exchange of zirconium phosphate

Science.gov (United States)

Liu, D. C.; Power, J. L.

1972-01-01

The Gd(+3)/H(+) ion exchange on a commercial zirconium phosphate ion exchanger was investigated in chloride, sulfate, and phosphate solutions of Gd(+3) at gadolinium concentrations of 0.001 to 1 millimole per cc and in the pH range of 0 to 3.5. Relatively low Gd(+3) capacities, in the range of 0.01 to 0.1 millimole per g of ion exchanger were found at room temperature. A significant difference in Gd(+3) sorption was observed, depending on whether the ion exchanger was converted from initial conditions of greater or lesser Gd(+3) sorption than the specific final conditions. Correlations were found between decrease in Gd(+3) capacity and loss of exchanger phosphate groups due to hydrolysis during washing and between increase in capacity and treatment with H3PO4. Fitting of the experimental data to ideal ion exchange equilibrium expressions indicated that each Gd(+3) ion is sorbed on only one site of the ion exchanger. The selectivity quotient was determined to be 2.5 + or - 0.4 at room temperature on gadolinium desorption in chloride solutions.

Antibodies to autoantigen targets in myasthenia and their value in clinical practice

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S. I. Dedaev

2014-01-01

Full Text Available Myasthenia gravis is a classic autoimmune disease, which clinical manifestations in the form of weakness and abnormal muscle fatigue, due to the damaging effect of polyclonal antibodies to different structures of the neuromuscular synapse and muscles. The study of autoimmune substrate with myasthenia is routine in many clinics dealing with the problems of neuromuscular pathology, and the identification of high concentration of serum antibodies to a number of antigenic structures is the gold standard in diagnosis.Determination of serum antibodies to various autoimmune targets is an important tool in clinical practice. The majority of patients shows the high concentration of antibodies to AchR that gives the opportunity to use it as an important diagnostic criterion. The specificity of changes in the concentration of AchR-antibodies due to pathogenetic treatment allows to objectify the suppression of autoimmune aggression and evaluate the reliability of remission. However, the absence of AchR-antibodies when there are clear clinical and electromyography signs of myasthenia gravis suggests an autoimmune attack against a number of other targets, the most studied of which is the MuSK. On the contrary, patients with myasthenia gravis associated with thymoma, almost always have a higher level of AchR-antibodies. The presence of thymoma is accompanied by the generation of antibodies to titin and RyR, which is also observed in persons with late-onset myasthenia without thymoma. High concentration of antibodies to these structures can be interpreted as a reliable sign of thymoma in patients younger than 60 years.

[Evaluation of serum levels of tick-borne encephalitis (TBE) virus antibodies after administration of FSME inject vaccine].

Science.gov (United States)

Pancewicz, Sławomir A; Hermanowska-Szpakowicz, Teresa

2002-01-01

The purpose of this work was to evaluate the changes of anti-TBE virus antibodies serum concentration 3 months after administration of FSME Inject vaccine. The detection of IgG antibodies against TBE virus was performed in sera of 106 forest workers aged mean = 41.5. These sera were examined twice before and after vaccine administration using FSME Kombi-Kit. According to producer's information the "safe" concentration, which protects from TBE virus infection, is over 11VE. In examination 126 (24.5%) sera showed concentration of examined antibodies lower than 11 VE but in 80 (75.5%) sera antibodies concentration was from 12 to 47 VE (mean = 24.15 VE). In the examination 2 significant increase of antibodies concentration was stated. In all sera the concentration ranged from 9 to 62 VE (mean = 39.83 VE). The administration of TBE vaccine booster causes quick increase of antibodies against TBE virus to the level which is considered to be protective against TBE virus infection.

Reaction between CO2 and phosphate to form carboxyphosphate?

International Nuclear Information System (INIS)

Knight, W.B.; Attwood, P.V.; Cleland, W.W.

1986-01-01

Carboxyphosphate (I) is thought to be an intermediate in the enzymic carboxylation of biotin by bicarbonate and MgATP, and a plausible mechanism of carboxyl transfer to the enolate of biotin involves decarboxylation to CO 2 and phosphate. Such a process would have to be reversible, however, as carboxylase reactions are reversible. To test this possibility, the authors undertook the synthesis of I under anhydrous conditions with a high mole fraction of CO 2 present. CO 2 was distilled into capillary tubes under vacuum containing dry tris-(tetrabutyl-ammonium)-phosphate in dimethylformamide. The tubes were sealed and warmed to -10 or 20 0 C and examined by 31 P NMR. Two resonances (1.7 ppm and -5.0 ppm) in addition to phosphate (3.3 ppm) were observed. The relative ratio of each peak to the phosphate one was dependent on the temperature and the concentrations of PO 4 3- and CO 2 . Upon freezing the tubes, cracking them, and release of the CO 2 , the two additional species decomposed slowly to PO 4 3- , and more rapidly to HPO 4 3- upon the addition of H 2 O. Under some conditions they observed an additional resonance (-7.0 ppm) which is most likely pyrophosphate (PP/sub i/). At high concentrations of PO 4 3- and CO 2 , PP/sub i/ was produced and precipitated from solution. The production of PP/sub i/ is most easily explained by attack of PO 4 3- on I. They are currently trying to identify the unknown species observed in the 31 P NMR spectra

Pore-Water Carbonate and Phosphate As Predictors of Arsenate Toxicity in Soil.

Science.gov (United States)

Lamb, Dane T; Kader, Mohammed; Wang, Liang; Choppala, Girish; Rahman, Mohammad Mahmudur; Megharaj, Mallavarapu; Naidu, Ravi

2016-12-06

Phytotoxicity of inorganic contaminants is influenced by the presence of competing ions at the site of uptake. In this study, interaction of soil pore-water constituents with arsenate toxicity was investigated in cucumber (Cucumis sativa L) using 10 contrasting soils. Arsenate phytotoxicity was shown to be related to soluble carbonate and phosphate. The data indicated that dissolved phosphate and carbonate had an antagonistic impact on arsenate toxicity to cucumber. To predict arsenate phytotoxicity in soils with a diverse range of soil solution properties, both carbonate and phosphate were required. The relationship between arsenic and pore-water toxicity parameters was established initially using multiple regression. In addition, based on the relationship with carbonate and phosphate we successively applied a terrestrial biotic ligand-like model (BLM) including carbonate and phosphate. Estimated effective concentrations from the BLM-like parametrization were strongly correlated to measured arsenate values in pore-water (R 2 = 0.76, P soils.

Isolation and characterization of a phosphate solubilizing heavy metal tolerant bacterium from River Ganga, West Bengal, India

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Dipak Paul

2015-12-01

Full Text Available Phosphates solubilizing bacterial (PSB strains were isolated from the jute mill effluent discharge area of the Ganga river water at Bansberia, West Bengal, India. Experimental studies found that the strain KUPSB16 was effective in solubilization of phosphate with phosphate solubilization index (SI = 3.14 in Pikovskaya’s agar plates along with maximum solubilized phosphate production of 208.18 g mL-1 in broth culture. Highest drop in pH value was associated with maximum amount of phosphate solubilization by the PSB strain KUPSB16 where pH decreased to 3.53 from initial value of 7.0±0.2. The isolated PSB strains were tested for tolerance against four heavy metals such as cadmium (Cd, chromium (Cr, lead (Pb and zinc (Zn at concentrations 1-15 mM. The results showed that most of the PSB isolates grew well at low concentrations of heavy metals and their number gradually decreased as the concentration increased. Isolated PSB strain KUPSB16 was tested for its multiple metal resistances. Minimal inhibitory concentrations (MIC for Cd2+, Cr6+, Pb2+ and Zn2+ in tris-minimal broth medium were 4.2, 5.5, 3.6 and 9.5 mM respectively. The MIC values for the metals studied on agar medium was higher than in broth medium and ranged from 4.8-11.0 mM. The isolated bacterial strain KUPSB16 was subjected to morphological, physiological and biochemical characterization and identified as the species of the genus Bacillus. The phosphate solubilizing bacterium possessing the properties of multiple heavy metal tolerance in heavy metal contaminated areas might be exploited for bioremediation studies in future.

Phosphate and arsenate removal efficiency by thermostable ferritin enzyme from Pyrococcus furiosus using radioisotopes

KAUST Repository

Sevcenco, Ana-Maria

2015-03-13

Oxo-anion binding properties of the thermostable enzyme ferritin from Pyrococcus furiosus were characterized with radiography. Radioisotopes 32P and 76As present as oxoanions were used to measure the extent and the rate of their absorption by the ferritin. Thermostable ferritin proved to be an excellent system for rapid phosphate and arsenate removal from aqueous solutions down to residual concentrations at the picomolar level. These very low concentrations make thermostable ferritin a potential tool to considerably mitigate industrial biofouling by phosphate limitation or to remove arsenate from drinking water.

Radium-226 in wetland birds from Florida phosphate mines

International Nuclear Information System (INIS)

Myers, O.B.; Marion, W.R.; O'Meara, T.E.; Roessler, C.E.

1989-01-01

Radium-226 is a naturally-occurring radionuclide found in enhanced levels at Florida phosphate mines. We inventoried levels of radium-226 in the tissues of 4 wetland bird species from 2 mined and 2 umined areas in Florida. Bone tissues of wood duck (Aix sponsa), mottled duck (Anas fulvigula), common moorhen (Gallinula chloropus), and double-crested cormorant (Phalacrocorax auritus) colleted at phosphate mines contained more radium-226 than tissues from unmined areas. Radium-226 concentrations in these birds were within guidelines inferred from radiological standards designed for human protection and should not adversely affect bird populations

Precaecal phosphorus digestibility of inorganic phosphate sources in male broilers

Science.gov (United States)

Bikker, P.; Spek, J. W.; Van Emous, R. A.; Van Krimpen, M. M.

2016-01-01

Abstract The aim of this study, comprising two experiments, was (1) to determine in Experiment 1 the relationship of incremental dietary P (phosphorus) content on precaecal digestible P in male broilers and (2) to determine in Experiment 2 the precaecal P digestibility of various inorganic P sources at marginal levels of P supply.In Experiment 1, a total of 260 male Ross 308 broilers were divided into groups of 10 birds per pen resulting in 8 replicates for treatment 1 and 6 replicates for treatments 2–4. Experimental diets were formulated to contain 4 incremental concentrations of digestible P by means of increasing concentrations of monocalcium phosphate (MCP). In the second experiment, 480-d-old male Ross 308 broilers were divided in groups of 12 birds per pen resulting in 16 replicates for the basal diet and 6 replicates for each test diet. A total of 4 inorganic P sources, MCP, monodicalcium phosphate (MDCP), dicalcium phosphate (DCP) and defluorinated phosphate (DFP) were added to the basal diet to determine the precaecal P digestibility. Three of the 4 inorganic P sources (MCP, MDCP and DCP) represented a mix of batches from different producers. At the end of both experiments, the chyme of the posterior part of the small intestine was collected. Digestibility of P and Ca was determined using titanium dioxide as indigestible marker.In Experiment 1, a reduction in precaecal digestibility of P was observed above an estimated precaecal digestible dietary P concentration of 4.8 g/kg.The precaecal P digestibility of the tested inorganic P sources in Experiment 2 was 78.3% for MCP, 59.0% for DCP, 70.7% for MDCP and 31.5% for DFP. PMID:27635437

Phosphate dynamics in an acidic mountain stream: Interactions involving algal uptake, sorption by iron oxide, and photoreduction

Science.gov (United States)

Tate, Cathy M.; Broshears, Robert E.; McKnight, Diane M.

1995-01-01

Acid mine drainage streams in the Rocky Mountains typically have few algal species and abundant iron oxide deposits which can sorb phosphate. An instream injection of radiolabeled phosphate (32P0,) into St. Kevin Gulch, an acid mine drainage stream, was used to test the ability of a dominant algal species, Ulothrix sp., to rapidly assimilate phosphate. Approximately 90% of the injected phosphate was removed from the water column in the 175-m stream reach. When shaded stream reaches were exposed to full sunlight after the injection ended, photoreductive dissolution of iron oxide released sorbed 32P, which was then also removed downstream. The removal from the stream was modeled as a first-order process by using a reactive solute transport transient storage model. Concentrations of 32P mass-’ of algae were typically lo-fold greater than concentrations in hydrous iron oxides. During the injection, concentrations of 32P increased in the cellular P pool containing soluble, low-molecular-weight compounds and confirmed direct algal uptake of 32P0, from water. Mass balance calculations indicated that algal uptake and sorption on iron oxides were significant in removing phosphate. We conclude that in stream ecosystems, PO, sorbed by iron oxides can act as a dynamic nutrient reservoir regulated by photoreduction.

Polyhexamethylene guanidine phosphate aerosol particles induce pulmonary inflammatory and fibrotic responses.

Science.gov (United States)

Kim, Ha Ryong; Lee, Kyuhong; Park, Chang We; Song, Jeong Ah; Shin, Da Young; Park, Yong Joo; Chung, Kyu Hyuck

2016-03-01

Polyhexamethylene guanidine (PHMG) phosphate was used as a disinfectant for the prevention of microorganism growth in humidifiers, without recognizing that a change of exposure route might cause significant health effects. Epidemiological studies reported that the use of humidifier disinfectant containing PHMG-phosphate can provoke pulmonary fibrosis. However, the pulmonary toxicity of PHMG-phosphate aerosol particles is unknown yet. This study aimed to elucidate the toxicological relationship between PHMG-phosphate aerosol particles and pulmonary fibrosis. An in vivo nose-only exposure system and an in vitro air-liquid interface (ALI) co-culture model were applied to confirm whether PHMG-phosphate induces inflammatory and fibrotic responses in the respiratory tract. Seven-week-old male Sprague-Dawley rats were exposed to PHMG-phosphate aerosol particles for 3 weeks and recovered for 3 weeks in a nose-only exposure chamber. In addition, three human lung cells (Calu-3, differentiated THP-1 and HMC-1 cells) were cultured at ALI condition for 12 days and were treated with PHMG-phosphate at set concentrations and times. The reactive oxygen species (ROS) generation, airway barrier injuries and inflammatory and fibrotic responses were evaluated in vivo and in vitro. The rats exposed to PHMG-phosphate aerosol particles in nanometer size showed pulmonary inflammation and fibrosis including inflammatory cytokines and fibronectin mRNA increase, as well as histopathological changes. In addition, PHMG-phosphate triggered the ROS generation, airway barrier injuries and inflammatory responses in a bronchial ALI co-culture model. Those results demonstrated that PHMG-phosphate aerosol particles cause pulmonary inflammatory and fibrotic responses. All features of fibrogenesis by PHMG-phosphate aerosol particles closely resembled the pathology of fibrosis that was reported in epidemiological studies. Finally, we expected that PHMG-phosphate infiltrated into the lungs in the form of

Elaboration and test of the method of separation of alkaline metals ions with tin phosphate

International Nuclear Information System (INIS)

Smirnov, G.I.; Chernyak, A.S.; Kostromina, O.N.; Kachur, N.Ya.; Shpeyzer, B.G.

1986-01-01

Present work is devoted to elaboration and test of the method of separation of alkaline metals ions with tin phosphate. Thus, the isotherms of sorption of lithium, sodium, potassium, rubidium and cesium ions with amorphous tin phosphate depending on their concentration, ph of solution, sorbent quantity are obtained. The parameters of extraction of potassium microquantities from sodium salts are defined. Ultra pure sodium chloride, sodium iodide, sodium sulphate, sodium nitrate, sodium nitrite, sodium phosphate are synthesized.

Phosphate Recovery From Sewage Sludge Containing Iron Phosphate

NARCIS (Netherlands)

Wilfert, P.K.

2018-01-01

The scope of this thesis was to lay the basis for a phosphate recovery technology that can be applied on sewage sludge containing iron phosphate. Such a technology should come with minimal changes to the existing sludge treatment configuration while keeping the use of chemicals or energy as small as

Comment on: "Recent revisions of phosphate rock reserves and resources: a critique" by Edixhoven et al. (2014) - Phosphate reserves and resources: what conceptions and data do stakeholders need for sustainable action?

Science.gov (United States)

Scholz, R. W.; Wellmer, F.-W.

2015-01-01

Several recent papers predict a scarcity of phosphate reserves in the near future. The paper by Edixhoven et al. (2014), for instance, expresses the doubts about whether the upward estimate of reserves by the IFDC (2010) and the USGS (2010) provide an accurate, reliable, and comparable picture, as they are based on reports that do not clearly differentiate between phosphate ore and phosphate products (i.e., marketable phosphate rock concentrate). Further the indistinct use of the terms reserves and resources is criticized. Edixhoven et al. ask for a differentiated inventory of world phosphate reserves including "guidelines which determine the appropriate drill hole distances." The claim that humanity is on the safe side with respect to future phosphate is supply is doubted as the validity of the IFDC's upgrading of the Moroccan data to 50 Gt phosphate is questioned. The present paper identifies and discusses basic conceptual errors of the paper by Edixhoven et al. and related papers that predict a short or mid-term phosphorus scarcity. These include the non-acknowledgment of the dynamic nature of reserves (which depends on price, technology, and innovation for exploiting low-grade deposits, etc.), the mixing of finiteness and staticness of the ultimate recoverable resources (i.e., phosphorus that may be mined economically in the long-term future), the improper use of the Hubbert analysis (which, e.g., simply uses the USGS estimates of reserves as a substitute of an estimate of ultimate recoverable resources) and the geostatistical naive/unprofessional demand for fixed drilling plans to assess reserves. We reconstruct the IFDC and USGS estimates and conclude that there is no evidence for considering the 50 Gt phosphate concentrate as an unreasonable estimate for Moroccan reserves. However, the partial mixing of different units (e.g., phosphate ore and phosphate concentrate or marketable product) in the USGS data may be avoided by improving the data base and using

Anti-glucagon antibodies in diabetes mellitus

Energy Technology Data Exchange (ETDEWEB)

Gergely, A; Koranyi, L; Halmos, T; Zsombok, M; Peterfy, F; Csizer, Z; Salamon, F; Tako, J

1973-01-01

Anti-insulin antibodies appear in the sera of patients treated with insulin lastingly. A high anti-insulin antibody level results in the development of insulin resistance. Most of the insulin preparations available on the market contain also glucagon as an impurity. It was therefore to be expected that in part of the patients, who had been treated with insulin lastingly, antibodies would be produced also against glucagon, and the presence of these was actually demonstrated. It is to be assumed that the anti-glucagon antibodies play a role in the pathomechanism of diabetes mellitus, mainly in its labile form. The possible presence of anti-glucagon antibodies must be taken into account when the glucagon concentration in the sera of diabetics is to be determined by means of radioimmunoassay (RIA). The specific antibodies in the serum give false results in the quantitative determination of glucagon. We have tested the sera of 10 diabetics who had been treated with insulin for at least 6 years. All patients were given protamine zinc and crystalline insulin preparations.

A mechanistic compartmental model for total antibody uptake in tumors.

Science.gov (United States)

Thurber, Greg M; Dane Wittrup, K

2012-12-07

Antibodies are under development to treat a variety of cancers, such as lymphomas, colon, and breast cancer. A major limitation to greater efficacy for this class of drugs is poor distribution in vivo. Localization of antibodies occurs slowly, often in insufficient therapeutic amounts, and distributes heterogeneously throughout the tumor. While the microdistribution around individual vessels is important for many therapies, the total amount of antibody localized in the tumor is paramount for many applications such as imaging, determining the therapeutic index with antibody drug conjugates, and dosing in radioimmunotherapy. With imaging and pretargeted therapeutic strategies, the time course of uptake is critical in determining when to take an image or deliver a secondary reagent. We present here a simple mechanistic model of antibody uptake and retention that captures the major rates that determine the time course of antibody concentration within a tumor including dose, affinity, plasma clearance, target expression, internalization, permeability, and vascularization. Since many of the parameters are known or can be estimated in vitro, this model can approximate the time course of antibody concentration in tumors to aid in experimental design, data interpretation, and strategies to improve localization. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of phosphate supplementation on oxygen delivery at high altitude

Science.gov (United States)

Jain, S. C.; Singh, M. V.; Rawal, S. B.; Sharma, V. M.; Divekar, H. M.; Tyagi, A. K.; Panwar, M. R.; Swamy, Y. V.

1987-09-01

In the present communication, effect of low doses of phosphate supplementation on short-term high altitude adaptation has been examined. Studies were carried out in 36 healthy, male, sea-level residents divided in a double blind fashion into drug and placebo treated groups. 3.2 mmol of phosphate were given orally to each subject of the drug treated group once a day for 4 days on arrival at an altitude of 3,500 m. Sequential studies were done in the subjects in both groups on the 3rd, 7th, 14th and 21st day of their altitude stay. Haemoglobin, haematocrit, erythrocyte and reticulocyte counts increased to the similar extent in both groups. Blood pH, pO2 and adenosine tri-phosphate (ATP) did not differ between the two groups. On 3rd day of the altitude stay, inorganic phosphate and 2,3-diphosphoglycerate (2,3 DPG) levels in the drug treated group increased significantly as compared to the placebo group. No significant difference in inorganic phosphate and 2,3 DPG was observed later on in the two groups. Psychological and clinical tests also indicated that the drug treated subjects felt better as compared to the placebo treated subjects. The present study suggests that low doses of phosphate increases circulating 2,3-DPG concentration which in turn brings about beneficial effect towards short term high altitude adaptation.

Inositol hexa-phosphate: a potential chelating agent for uranium

International Nuclear Information System (INIS)

Cebrian, D.; Tapia, A.; Real, A.; Morcillo, M.A.

2007-01-01

Chelation therapy is an optimal method to reduce the radionuclide-related risks. In the case of uranium incorporation, the treatment of choice is so far i.v infusion of a 1.4% sodium bicarbonate solution, but the efficacy has been proved to be not very high. In this study, we examine the efficacy of some substances: bicarbonate, citrate, diethylenetriamine pentaacetic acid (DTPA), ethidronate (EHBP) and inositol hexa-phosphate (phytic acid) to chelate uranium using a test developed by Braun et al. Different concentrations of phytic acid, an abundant component of plant seeds that is widely distributed in animal cells and tissues in substantial levels, were tested and compared to the same concentrations of sodium citrate, bicarbonate, EHBP and DTPA. The results showed a strong affinity of inositol hexa-phosphate for uranium, suggesting that it could be an effective chelating agent for uranium in vivo. (authors)

Controlled adsorption and release onto calcium phosphates materials and drug delivery applications

Directory of Open Access Journals (Sweden)

Barroug A.

2013-11-01

Full Text Available The adsorptive properties of synthetic calcium phosphates analogous to bone mineral were examined with respect to cisplatin and risedronate, two biological active drugs; the uptake and release experiments were carried out under various conditions in order to understand the basic mechanism of interaction. The effect of temperature and solution composition were highlighted and discussed. The adsorption results obtained for the therapeutic agents demonstrated that, depending on the conditions investigated (nature of the sorbent, concentration range, ionic composition, temperature…, the shape of the isotherms is of Freundlich or Langmuir type. The adsorption is described as an ion-exchange process in dilute solutions, while the interaction appears to be reactive for concentrated solutions (dissolution of mineral ions from the apatite substrate and formation of soluble calcium complex and/or precipitation of calcium salts involving sorbate molecules. The information gained on the surface reactivity of calcium phosphate were exploited to associate an antibiotic to calcium phosphate cements for drug delivery applications. The specimens were obtained by combination of calcium phosphate and calcium carbonate powders upon mixing with water. The physicochemical properties of the paste were altered by the drug loading method (in the liquid or solid phase. Thus, a dose-dependent effect was noticed for the paste setting time, hardening and the release process.

Removal of phosphate using copper-loaded polymeric ligand exchanger prepared by radiation grafting of polypropylene/polyethylene (PP/PE) nonwoven fabric

Science.gov (United States)

Barsbay, Murat; Kavaklı, Pınar Akkaş; Güven, Olgun

2010-03-01

A novel polymeric ligand exchanger (PLE) was prepared for the removal of phosphate ions from water. 2,2'-dipyridylamine (DPA), a bidentate ligand forming compound with high coordination capacity with a variety of metal ions was bound to glycidyl methacrylate (GMA) grafted polypropylene/polyethylene (PP/PE) nonwoven fabric synthesized by radiation-induced grafting technique. DPA attachment on epoxy ring of GMA units was tested in different solvents, i.e. methanol, ethanol, dioxane and dimethylsulfoxide (DMSO). The highest amount of modification was achieved in dioxane. In order to prepare the corresponding PLE for the removal of phosphate, DPA-immobilized fabric was loaded with Cu(II) ions. Phosphate adsorption experiments were performed in batch mode at different pH (5-9) and phosphate concentrations. The fabric was found to be effective for the removal of phosphate ions. At every stage of preparation and use, the nonwoven fabric was characterized by thermal (i.e. DSC and TGA) and spectroscopic (FTIR) methods. Competitive adsorption experiments were also carried out using two solutions with different concentration levels at pH 7 to see the effect of competing ions. Phosphate adsorption was found to be effective and selective from solutions having trace amounts of competitive anions. It is expected that the novel PLE synthesized can be used for the removal of phosphate ions in low concentrations over a large range of pH.

Effect upon biocompatibility and biocorrosion properties of plasma electrolytic oxidation in trisodium phosphate electrolytes.

Science.gov (United States)

Kim, Yu-Kyoung; Park, Il-Song; Lee, Kwang-Bok; Bae, Tae-Sung; Jang, Yong-Seok; Oh, Young-Min; Lee, Min-Ho

2016-03-01

Surface modification to improve the corrosion resistance and biocompatibility of the Mg-Al-Zn-Ca alloy was conducted via plasma electrolytic oxidation (PEO) in an electrolyte that included phosphate. Calcium phosphate can be easily induced on the surface of a PEO coating that includes phosphate in a physiological environment because Ca(2+) ions in body fluids can be combined with PO4 (3-). Cytotoxicity of the PEO coating formed in electrolytes with various amounts of Na3PO4 was identified. In particular, the effects that PEO films have upon oxidative stress and differentiation of osteoblast activity were studied. As the concentration of Na3PO4 in the electrolyte increased, the oxide layer was found to become thicker, which increased corrosion resistance. However, the PEO coating formed in electrolytes with over 0.2 M of added Na3PO4 exhibited more microcracks and larger pores than those formed in smaller Na3PO4 concentrations owing to a large spark discharge. A nonuniform oxide film that included more phosphate caused more cytotoxicity and oxidative stress, and overabundant phosphate content in the oxide layer interrupted the differentiation of osteoblasts. The corrosion resistance of the magnesium alloy and the thickness of the oxide layer were increased by the addition of Na3PO4 in the electrolyte for PEO treatment. However, excessive phosphate content in the oxide layer led to oxidative stress, which resulted in reduced cell viability and activity.

In Vivo EPR Assessment of pH, pO2, Redox Status, and Concentrations of Phosphate and Glutathione in the Tumor Microenvironment.

Science.gov (United States)

Bobko, Andrey A; Eubank, Timothy D; Driesschaert, Benoit; Khramtsov, Valery V

2018-03-16

This protocol demonstrates the capability of low-field electron paramagnetic resonance (EPR)-based techniques in combination with functional paramagnetic probes to provide quantitative information on the chemical tumor microenvironment (TME), including pO2, pH, redox status, concentrations of interstitial inorganic phosphate (Pi), and intracellular glutathione (GSH). In particular, an application of a recently developed soluble multifunctional trityl probe provides unsurpassed opportunity for in vivo concurrent measurements of pH, pO2 and Pi in Extracellular space (HOPE probe). The measurements of three parameters using a single probe allow for their correlation analyses independent of probe distribution and time of the measurements.

Inhalation dose assessment inside various storage godowns of a phosphatic fertiliser plant

International Nuclear Information System (INIS)

Shukla, V.K.; Eapen, C.D.; Mishra, U.C.

1995-01-01

The paper presents the assessment of inhalation dose from 222 Rn daughters received by the persons working inside various godowns, meant for storing rock phosphate and different types of phosphatic fertilisers produced by a plant at Bombay. The dose assessment was made by measuring the respirable airborne concentrations of 222 Rn daughters inside the godowns. Rock phosphate is the base material for the production of phosphatic fertilisers and it contains significant quantities of 226 Ra. 226 Ra activity in rock phosphate from different places is ranging between 5 (Udaipur, India) to 1480 Bq/kg (Florida, USA) and its range in NP: 20-20-0 and NPK: 15-15-15 type fertilisers is 254 to 272 Bq/kg and 127 to 208 Bq/kg respectively. 226 Ra is the source of emanation of 222 Rn inside the godowns. It was observed that though the specific activity of 218 Po, 214 Pb and 214 Bi in the total airborne particulate matter was higher inside the rock phosphate godown but the specific activity of the aforementioned radionuclides in the respirable fractions inside the phosphatic fertilisers' godown were more. The reasons for these observations are discussed in the paper. (author). 7 refs., 2 tabs

Phosphate-a poison for humans?

Science.gov (United States)

Komaba, Hirotaka; Fukagawa, Masafumi

2016-10-01

Maintenance of phosphate balance is essential for life, and mammals have developed a sophisticated system to regulate phosphate homeostasis over the course of evolution. However, due to the dependence of phosphate elimination on the kidney, humans with decreased kidney function are likely to be in a positive phosphate balance. Phosphate excess has been well recognized as a critical factor in the pathogenesis of mineral and bone disorders associated with chronic kidney disease, but recent investigations have also uncovered toxic effects of phosphate on the cardiovascular system and the aging process. Compelling evidence also suggests that increased fibroblastic growth factor 23 and parathyroid hormone levels in response to a positive phosphate balance contribute to adverse clinical outcomes. These insights support the current practice of managing serum phosphate in patients with advanced chronic kidney disease, although definitive evidence of these effects is lacking. Given the potential toxicity of excess phosphate, the general population may also be viewed as a target for phosphate management. However, the widespread implementation of dietary phosphate intervention in the general population may not be warranted due to the limited impact of increased phosphate intake on mineral metabolism and clinical outcomes. Nonetheless, the increasing incidence of kidney disease or injury in our aging society emphasizes the potential importance of this issue. Further work is needed to more completely characterize phosphate toxicity and to establish the optimal therapeutic strategy for managing phosphate in patients with chronic kidney disease and in the general population. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Uranium Sequestration by Aluminum Phosphate Minerals in Unsaturated Soils

International Nuclear Information System (INIS)

Jerden, James L. Jr.

2007-01-01

A mineralogical and geochemical study of soils developed from the unmined Coles Hill uranium deposit (Virginia) was undertaken to determine how phosphorous influences the speciation of uranium in an oxidizing soil/saprolite system typical of the eastern United States. This paper presents mineralogical and geochemical results that identify and quantify the processes by which uranium has been sequestered in these soils. It was found that uranium is not leached from the saturated soil zone (saprolites) overlying the deposit due to the formation of a sparingly soluble uranyl phosphate mineral of the meta-autunite group. The concentration of uranium in the saprolites is approximately 1000 mg uranium per kg of saprolite. It was also found that a significant amount of uranium was retained in the unsaturated soil zone overlying uranium-rich saprolites. The uranium concentration in the unsaturated soils is approximately 200 mg uranium per kg of soil (20 times higher than uranium concentrations in similar soils adjacent to the deposit). Mineralogical evidence indicates that uranium in this zone is sequestered by a barium-strontium-calcium aluminum phosphate mineral of the crandallite group (gorceixite). This mineral is intimately inter-grown with iron and manganese oxides that also contain uranium. The amount of uranium associated with both the aluminum phosphates (as much as 1.4 weight percent) has been measured by electron microprobe micro-analyses and the geochemical conditions under which these minerals formed has been studied using thermodynamic reaction path modeling. The geochemical data and modeling results suggest the meta-autunite group minerals present in the saprolites overlying the deposit are unstable in the unsaturated zone soils overlying the deposit due to a decrease in soil pH (down to a pH of 4.5) at depths less than 5 meters below the surface. Mineralogical observations suggest that, once exposed to the unsaturated environment, the meta-autunite group

Cation mobility in H+/Na+ ion exchange products of acid tantalum and zirconium phosphates

International Nuclear Information System (INIS)

Tarnopol'skij, V.A.; Yaroslavtsev, A.B.

2000-01-01

Ionic conductivity of Na + /H + exchange products on acid zirconium phosphate with different substitution degree and on acid tantalum phosphate, where ion exchange occurs via formation of a continuous series of solid solutions, was studied by the method of conductometry. It was ascertained that ionic conductivity decreases monotonously with growth in substitution degree of H + for Na + in acid tantalum phosphate. Anomalous increase in ionic conductivity of ion exchange products on acid zirconium phosphate with a low substitution degree has been detected for the first time. Formation of a double electric layer with a high concentration of cationic defects on the interface surface is the reason for increase in ionic conductivity [ru

Quantitative Mechanistic Description of Natural Radionuclide and Iron Sorption on phosphate Fertilizer Materials

International Nuclear Information System (INIS)

Kamel, N.H.M.

2008-01-01

The mean activity values of the radionuclide 226 Ra, 238 U and 232 Th decay series, and the radioactive isotopes of 40 K in Bq/kg dry weight of the phosphate ore (Pho-ore), single super phosphate granules, (SSP-G), single super phosphate powder (SSP-P), triple super phosphate (TSP), and phosphogypsum (CaSO 4 ) samples were determined. CaSO 4 sample was found to contain, 300 Bq/kg of radioactive 238 U which is less than the values found in other studied phosphate samples. CaSO 4 sample was found to contain the highest amount of 226 Ra concentration value of 850 Bq/kg. Phosphate fertilizer components are acidic character, therefore, the solid surfaces will in general acquire a surface electric charge when contact with polar solvent such as water. The net electric charge obtained through uptake or release of potential determining ions (e.g, H + or OH - ). Thus the solid surfaces tend to adsorb and/or release of different ions to maintain neutral. The aim of this study is to determine the electric charge and the surface electric potential at the phosphate fertilizer materials

Beneficiation studies of an uranium siliceous - phosphate ore

International Nuclear Information System (INIS)

Bruno, J.B.; Santos, A.T.; Santos Benedetto, J. dos

1980-01-01

The consolidation of the beneficiation studies of a low-grade uranium siliceous - phosphate ore (11% P 2 O 5 ) from Itataia region in the Northeast of Brazil, owned by Empresas Nucleares Brasileiras S.A. - NUCLEBRAS, are presented. Laboratory studies using froth flotation technique and applying statistical methods for data evaluation were made. Pilot plant tests in a 120 Kg/h scale were conducted as a consequence of the bench scale tests. The developed process using tall-oil as collector and starch as depressant gave a total yield of 80% for the P 2 O 5 and 71% the U 3 O 8 , for a 33% P 2 O 5 phosphate concentrate. (Author) [pt

Use of a La(III)-modified bentonite for effective phosphate removal from aqueous media

Energy Technology Data Exchange (ETDEWEB)

Kuroki, Vivian; Bosco, Giulianna E. [Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adélia, 166, Santo André CEP 09210-170, SP (Brazil); Fadini, Pedro S.; Mozeto, Antonio A. [Laboratório de Biogeoquímica Ambiental, Núcleo de Estudos, Diagnósticos e Intervenções Ambientais, Departamento de Química, Universidade Federal de São Carlos, Cx. Postal 676, São Carlos CEP 13565-905, SP (Brazil); Cestari, Antonio R. [Department of Chemistry/CCET, Universidade Federal de Sergipe, São Cristóvão CEP 49100-000, SE (Brazil); Carvalho, Wagner A., E-mail: wagner.carvalho@ufabc.edu.br [Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adélia, 166, Santo André CEP 09210-170, SP (Brazil)

2014-06-01

Highlights: • A phosphate adsorbent was prepared from unpurified natural bentonite. • Physisorption was found to the main phosphate interaction mechanism. • The retention has reached 95% of the phosphate present in solution at room temperature. • The rate sorption was about 4 times faster than commercial phosphate adsorbents. - Abstract: A bentonite from the Northeast Brazilian region was modified with lanthanum (NT-25La) using an ion exchange process. Lanthanum incorporation in the natural clay, as well as the properties of the clay materials, were confirmed by X-ray diffraction, X-ray fluorescence, specific surface area and scanning electron microscopy (SEM/EDX). Phosphate adsorption equilibrium and kinetic tests were performed at different temperatures. The adsorption data have shown that NT-25La reaches equilibrium between modified clay and phosphate solution within 60 min of contact. The phosphate retention at room temperature reached 95%, when initial phosphate concentration in solution was 5 mg L{sup −1}. A kinetic-order variable model provided satisfactory fitting of the kinetic data. Adsorption of phosphate was best described by a Langmuir isotherm, with maximum phosphate sorption capacity of 14.0 mg g{sup −1}. Two distinct adsorption mechanisms were observed that may influence the adsorption processes. The investigation pointed out that the phosphate adsorption occurs via physisorption processes and that the use of NT-25La provides a maximum phosphate sorption capacity higher than many commercial adsorbents.

Biomimetic fabrication of antibacterial calcium phosphates mediated by polydopamine.

Science.gov (United States)

Forte, Lucia; Torricelli, Paola; Bonvicini, Francesca; Boanini, Elisa; Gentilomi, Giovanna Angela; Lusvardi, Gigliola; Della Bella, Elena; Fini, Milena; Vecchio Nepita, Edoardo; Bigi, Adriana

2018-01-01

In this work we developed new antibacterial composite materials using polydopamine (PDA) to trigger the deposition of silver nanoparticles (AgNPs) onto calcium phosphates, namely octacalcium phosphate (OCP) and α-tricalcium phosphate (αTCP). Functionalization of OCP and αTCP with a self-polymerized polydopamine layer was obtained by soaking the calcium phosphates in dopamine solution. The PDA surface of functionalized calcium phosphates (OCPd and αTCPd) promoted the deposition of AgNPs by reducing silver ions when soaked in a silver nitrate solution. The amount of deposited AgNPs can be modulated by varying the concentration of silver nitrate solution and the type of substrate. The results of in vitro tests carried out with osteoblast-like MG63 cells indicate that the combination of AgNPs with OCP provides more biocompatible materials than those obtained using αTCP as substrate. In particular, the study of osteoblast activity and differentiation was focused on the samples OCPdAg5 (silver content=8.2wt%) and αTCPdAg5 (silver content=4.7wt%), which did not show any cytotoxicity, and compared with those obtained on pure OCP and αTCP. The results demonstrate that the AgNPs loaded materials support osteoblast viability and differentiation, whereas they significantly inhibit the growth of relevant antibiotic-resistant pathogenic bacteria. Copyright © 2017 Elsevier Inc. All rights reserved.

Performance evaluation of a continuous bipolar electrocoagulation/electrooxidation-electroflotation (ECEO-EF) reactor designed for simultaneous removal of ammonia and phosphate from wastewater effluent

Energy Technology Data Exchange (ETDEWEB)

Mahvi, Amir Hossein, E-mail: ahmahvi@yahoo.com [Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Enghelab Street, Tehran (Iran, Islamic Republic of); National Institute of Health Research, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Ebrahimi, Seyed Jamal Al-din [Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Enghelab Street, Tehran (Iran, Islamic Republic of); Mesdaghinia, Alireza, E-mail: mesdaghinia@sina.tums.ac.ir [Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Enghelab Street, Tehran (Iran, Islamic Republic of); Gharibi, Hamed, E-mail: hgharibi65@gmail.com [Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Enghelab Street, Tehran (Iran, Islamic Republic of); Sowlat, Mohammad Hossein, E-mail: hsowlat@gmail.com [Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Enghelab Street, Tehran (Iran, Islamic Republic of)

2011-09-15

Highlights: {center_dot} Max removal efficiencies of the reactor for both ammonia and phosphate were 99%. {center_dot} Corresponding efficiencies under actual wastewater conditions were 98%. {center_dot} Optimum removal conditions were neutral pH and current density of 3 A. {center_dot} Lower influent concentration and higher detention time favored removal efficiency. {center_dot} Besides ammonia and phosphate, Al{sup 3+} plate enables removal of nitrite and nitrate. - Abstract: The present study aimed to evaluate the performance of a continuous bipolar ECEO-EF reactor designed for simultaneous removal of ammonia and phosphate from wastewater effluent. The reactor was comprised of two distinct units: electrochemical and separation. In the electrochemical unit, Al, stainless steel, and RuO{sub 2}/Ti plates were used. All the measurements were performed according to the standard methods. Maximum efficiency of the reactor for phosphate removal was 99% at pH of 6, current density of 3 A, detention time of 60 min, and influent phosphate concentration of 50 mg/l. The corresponding value for ammonia removal was 99% at a pH of 7 under the same operational conditions as for phosphate removal. For both phosphate and ammonia, the removal efficiency was highest at neutral pH, with higher current densities, and with lower influent concentrations. In addition to removal of phosphate and ammonia, application of the Al{sup 3+} plates enabled the removal of nitrite and nitrate, which may be present in wastewater effluent and are also products of the electrochemical process. The reactor was also able to decrease the concentrations of phosphate, ammonia, and COD under actual wastewater conditions by 98%, 98%, and 72%, respectively. According to the results of the present study, the reactor can be used for efficient removal of ammonia and phosphate from wastewater.

Extraction of antimony from nitric acid solutions using tributyl phosphate. II. Tributyl phosphate-antimony(V)-nitric acid system

International Nuclear Information System (INIS)

Lakaev, V.S.; Smelov, V.S.

1989-01-01

The extraction of pentavalent antimony from nitric acid solutions using tributyl phosphate has been investigated. A possible mechanism for the extraction of antimony(V) has been determined and the (pre)concentration constant for the process has been calculated. The composition of the extracted antimony(V) complex has been deduced. A negative effect of temperature on the distribution coefficient for antimony(V) has also been demonstrated

Contribution of Drinking Water Softeners to Daily Phosphate Intake in Slovenia.

Science.gov (United States)

Jereb, Gregor; Poljšak, Borut; Eržen, Ivan

2017-10-06

The cumulative phosphate intake in a typical daily diet is high and, according to several studies, already exceeds recommended values. The exposure of the general population to phosphorus via drinking water is generally not known. One of the hidden sources of phosphorus in a daily diet is sodium polyphosphate, commonly used as a drinking water softener. In Slovenia, softening of drinking water is carried out exclusively within the internal (household) drinking water supply systems to prevent the accumulation of limescale. The aim of the study was to determine the prevalence of sodium phosphates in the drinking water in Slovenia in different types of buildings, to determine residents' awareness of the presence of chemical softeners in their drinking water, and to provide an exposure assessment on the phosphorus intake from drinking water. In the current study, the presence of phosphates in the samples of drinking water was determined using a spectrophotometric method with ammonium molybdate. In nearly half of the samples, the presence of phosphates as water softeners was confirmed. The measured concentrations varied substantially from 0.2 mg PO4/L to 24.6 mg PO4/L. Nearly 70% of the respondents were not familiar with the exact data on water softening in their buildings. It follows that concentrations of added phosphates should be controlled and the consumers should be informed of the added chemicals in their drinking water. The health risks of using sodium polyphosphate as a drinking water softener have not been sufficiently investigated and assessed. It is highly recommended that proper guidelines and regulations are developed and introduced to protect human health from adverse effects of chemicals in water intended for human consumption.

[A spectrum of neurological diseases with anti-VGKC antibody].

Science.gov (United States)

Arimura, Kimiyoshi; Watanabe, Osamu; Nagado, Tatsui

2007-11-01

Anti-VGKC antibody causing peripheral nerve hyperexcitability is already an established clinical entity. Recently, many patients with non-herpetic limbic encephalitis (NHLE) with anti-VGKC antibody have been reported. The characteristic clinical features are low serum Na+ concentration and good response to immunotherapy. Anti-VGK antibody positive NHLE is relatively frequent among immune-mediated NHLE. It is important to know that this disease is responsive to immunotherapy. Furthermore, anti-VGKC antibody is also positive in some intractable epilepsies. These findings suggest that anti-VGKC is correlated with hyperexcitability in both the peripheral and central nervous system and that the spectrum of anti-VGKC antibody syndrome is now expanding.

Degradation of bis- p -nitrophenyl phosphate using zero-valent iron nanoparticles

International Nuclear Information System (INIS)

Valle-Orta, Maiby; Guerrero, Rubén Saldivar; Díaz, David; Dubé, Inti Zumeta; Quiñonez, José Luis Ortiz

2017-01-01

Phosphate esters are employed in some agrochemical formulations and have long life time in the Environment. They are neurotoxic to mammals and it is very difficult to hydrolyze them. It is easy to find papers in the literature dealing with transition metal complexes used in the hydrolysis processes of organophosphorous compounds. However, there are few reports related with degradation of phosphate esters with inorganic nanoparticles. In this work bis-4-nitrophenyl phosphate (BNPP) was used as an agrochemical agent model. The BNPP interaction with zero-valent iron nanoparticles (ZVI NPs), in aqueous media, was searched. The concentration of BNPP was 1000 times higher than the ZVI NPs concentration. The average size of the used iron nanoparticles was 10.2 ± 3.2 nm. The BNPP degradation process was monitored by means of UV-visible method. Initially, the BNPP hydrolysis happens through the P-O bonds breaking-off under the action of the ZVI NPs. Subsequently, the nitro groups were reduced to amine groups. The overall process takes place in 10 minutes. The reaction products were identified employing standard substances in adequate concentrations. The iron by-products were isolated and characterized by X-RD. These iron derivatives were identified as magnetite (Fe 3 O 4 ) and/or maghemite (γ-Fe 2 O 3 ) and lepidocrocite (γ-FeOOH). A suggested BNPP degradation mechanism will be discussed. (paper)

Use of osmolytes during solubilization and reconstitution of phosphate: sugar phosphate antiport from bacteria

International Nuclear Information System (INIS)

Ambudkar, S.V.; Sonna, L.A.; Maloney, P.C.

1986-01-01

Phosphate:2-deoxyglucose 6-phosphate (Pi:2DG6P) antiport was extracted from Streptococcus lactis or Staphylococcus aureus with 1.1% octylglucoside in the presence of 0.37% E. coli lipid and reconstituted by detergent dilution. Because previous work suggested inactivation at an early stage, the authors introduced protein stabilants during solubilization. When 20% glycerol was used, proteoliposomes showed a 20-fold increase in 32 Pi transport. This enhanced recovery required phospholipid plus glycerol, and was found only when both were added together with the detergent. Glycerol protection yielded proteoliposomes in which antiporters retained their normal kinetic properties, and Pi exchange by the streptococcal example gave a maximal rate (200-400 nmol/min per mg protein) and a turnover number (30-50/s) which suggested that inactivation had been avoided. Further study showed that 20% glycerol could be replaced by equally high concentrations of compounds classified as osmolytes polyols (erythritol, xylitol, sorbitol), sugars (glucose, trehalose) and certain amino acids (glycine, proline, but not valine). The authors suggest that osmolytes may be used to fully stabilize chemiosmotic transporters during reconstitution

TTPIXE analysis of phosphate rocks and phosphogypsum

International Nuclear Information System (INIS)

Martin, J.E.; Respaldiza, M.A.; Ontalba, M.A.; Garcia-Tenorio, R.; Bolivar, J.P.; Silva, M.F. da

1999-01-01

The TTPIXE technique was used for the determination of the concentrations of major, minor and trace elements in phosphate rock and phosphogypsum samples. All the samples came from a fertilizer industry site in Huelva (SW of Spain). The analyses were done using proton beams from the 3 MV Van de Graaff accelerator of the 'Instituto Tecnologico e Nuclear' (ITN), Sacavem (Portugal). The aim was to obtain data about the distribution of the different elements in the process of P 2 O 5 production in the factory. The information obtained allowed evaluation of the effectiveness of the chemical treatment employed, and gave a detailed information about the elemental composition of phosphogypsum, the main by-product of phosphate fertilizer production. These data can be useful to define the phosphogypsum management and to evaluate its environmental impact

Randomized Cross-Sectional Study to Compare HIV-1 Specific Antibody and Cytokine Concentrations in Female Genital Secretions Obtained by Menstrual Cup and Cervicovaginal Lavage.

Science.gov (United States)

Archary, Derseree; Liebenberg, Lenine J; Werner, Lise; Tulsi, Sahil; Majola, Nelisile; Naicker, Nivashnee; Dlamini, Sarah; Hope, Thomas J; Samsunder, Natasha; Abdool Karim, Salim S; Morris, Lynn; Passmore, Jo-Ann S; Garrett, Nigel J

2015-01-01

Optimizing methods for genital specimen collection to accurately characterize mucosal immune responses is a priority for the HIV prevention field. The menstrual cup (MC) has been proposed as an alternative to other methods including cervicovaginal lavage (CVL), but no study has yet formally compared these two methods. Forty HIV-infected, antiretroviral therapy-naïve women from the CAPRISA 002 acute HIV infection cohort study were randomized to have genital fluid collected using the MC with subsequent CVL, or by CVL alone. Qualitative data, which assessed levels of comfort and acceptability of MC using a 5-point Likert scale, was collected. Luminex multiplex assays were used to measure HIV-specific IgG against multiple gene products and 48 cytokines. The majority (94%) of participants indicated that insertion, wearing and removal of the MC was comfortable. Nineteen MCs with 18 matching, subsequent CVLs and 20 randomized CVLs were available for analysis. Mucosal IgG responses against four HIV-antigens were detected in 99% of MCs compared to only 80% of randomized CVLs (p = 0.029). Higher specific antibody activity and total antibodies were observed in MCs compared to CVL (all p<0.001). In MCs, 42/48 (88%) cytokines were in the detectable range in all participants compared to 27/48 (54%) in CVL (p<0.001). Concentrations of 22/41 cytokines (53.7%) were significantly higher in fluid collected by MC. Both total IgG (r = 0.63; p = 0.005) and cytokine concentrations (r = 0.90; p<0.001) correlated strongly between MC and corresponding post-MC CVL. MC sampling improves the detection of mucosal cytokines and antibodies, particularly those present at low concentrations. MC may therefore represent an ideal tool to assess immunological parameters in genital secretions, without interfering with concurrent collection of conventional CVL samples.

Randomized Cross-Sectional Study to Compare HIV-1 Specific Antibody and Cytokine Concentrations in Female Genital Secretions Obtained by Menstrual Cup and Cervicovaginal Lavage.

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Derseree Archary

Full Text Available Optimizing methods for genital specimen collection to accurately characterize mucosal immune responses is a priority for the HIV prevention field. The menstrual cup (MC has been proposed as an alternative to other methods including cervicovaginal lavage (CVL, but no study has yet formally compared these two methods.Forty HIV-infected, antiretroviral therapy-naïve women from the CAPRISA 002 acute HIV infection cohort study were randomized to have genital fluid collected using the MC with subsequent CVL, or by CVL alone. Qualitative data, which assessed levels of comfort and acceptability of MC using a 5-point Likert scale, was collected. Luminex multiplex assays were used to measure HIV-specific IgG against multiple gene products and 48 cytokines.The majority (94% of participants indicated that insertion, wearing and removal of the MC was comfortable. Nineteen MCs with 18 matching, subsequent CVLs and 20 randomized CVLs were available for analysis. Mucosal IgG responses against four HIV-antigens were detected in 99% of MCs compared to only 80% of randomized CVLs (p = 0.029. Higher specific antibody activity and total antibodies were observed in MCs compared to CVL (all p<0.001. In MCs, 42/48 (88% cytokines were in the detectable range in all participants compared to 27/48 (54% in CVL (p<0.001. Concentrations of 22/41 cytokines (53.7% were significantly higher in fluid collected by MC. Both total IgG (r = 0.63; p = 0.005 and cytokine concentrations (r = 0.90; p<0.001 correlated strongly between MC and corresponding post-MC CVL.MC sampling improves the detection of mucosal cytokines and antibodies, particularly those present at low concentrations. MC may therefore represent an ideal tool to assess immunological parameters in genital secretions, without interfering with concurrent collection of conventional CVL samples.

Radioactivity contents in dicalcium phosphate and the potential radiological risk to human populations

International Nuclear Information System (INIS)

Casacuberta, N.; Masque, P.; Garcia-Orellana, J.; Bruach, J.M.; Anguita, M.; Gasa, J.; Villa, M.; Hurtado, S.; Garcia-Tenorio, R.

2009-01-01

Potentially harmful phosphate-based products derived from the wet acid digestion of phosphate rock represent one of the most serious problems facing the phosphate industry. This is particularly true for dicalcium phosphate (DCP), a food additive produced from either sulphuric acid or hydrochloric acid digestion of raw rock material. This study determined the natural occurring radionuclide concentrations of 12 DCP samples and 4 tricalcium phosphate (TCP) samples used for animal and human consumption, respectively. Metal concentrations (Al, Fe, Zn, Cd, Cr, As, Hg, Pb and Mg) were also determined. Samples were grouped into three different clusters (A, B, C) based on their radionuclide content. Whereas group A is characterized by high activities of 238 U, 234 U (∼10 3 Bq kg -1 ), 210 Pb (2 x 10 3 Bq kg -1 ) and 210 Po (∼800 Bq kg -1 ); group B presents high activities of 238 U, 234 U and 230 Th (∼10 3 Bq kg -1 ). Group C was characterized by very low activities of all radionuclides ( -1 ). Differences between the two groups of DCP samples for animal consumption (groups A and B) were related to the wet acid digestion method used, with group A samples produced from hydrochloric acid digestion, and group B samples produced using sulphuric acid. Group C includes more purified samples required for human consumption. High radionuclide concentrations in some DCP samples (reaching 2 x 10 3 and 10 3 Bq kg -1 of 210 Pb and 210 Po, respectively) may be of concern due to direct or indirect radiological exposure via ingestion. Our experimental results based on 210 Pb and 210 Po within poultry consumed by humans, suggest that the maximum radiological doses are 11 ± 2 μSv y -1 . While these results suggest that human health risks are small, additional testing should be conducted.

A Phex Mutation in a Murine Model of X-linked Hypophosphatemia Alters Phosphate Responsiveness of Bone Cells

OpenAIRE

Ichikawa, Shoji; Austin, Anthony M.; Gray, Amie K.; Econs, Michael J.

2012-01-01

Mutations in the PHEX gene cause X-linked hypophosphatemia (XLH). Hypophosphatemia in XLH results from increased circulating levels of a phosphaturic hormone, fibroblast growth factor 23 (FGF23), which inhibits renal phosphate reabsorption and 1,25-dihydroxyvitamin D (calcitriol) synthesis. The current standard therapy for XLH – high dose phosphate and calcitriol – further increases FGF23 concentrations, suggesting that patients with XLH may have an altered response to extracellular phosphate...

Transmission spectra study of sulfate substituted potassium dihydrogen phosphate

KAUST Repository

LI, LIANG

2013-04-18

Potassium dihydrogen phosphate (KDP) crystals with different amounts of sulfate concentration were grown and the transmittance spectrum was studied. A crystal with high sulfate replacement density exhibits heavy absorption property in the ultraviolet region which confirms and agrees well with former results. © 2013 Astro Ltd.

Dietary phosphate restriction normalizes biochemical and skeletal abnormalities in a murine model of tumoral calcinosis.

Science.gov (United States)

Ichikawa, Shoji; Austin, Anthony M; Gray, Amie K; Allen, Matthew R; Econs, Michael J

2011-12-01

Mutations in the GALNT3 gene cause tumoral calcinosis characterized by ectopic calcifications due to persistent hyperphosphatemia. We recently developed Galnt3 knockout mice in a mixed background, which had hyperphosphatemia with increased bone mineral density (BMD) and infertility in males. To test the effect of dietary phosphate intake on their phenotype, Galnt3 knockout mice were generated in the C57BL/6J strain and fed various phosphate diets: 0.1% (low), 0.3% (low normal), 0.6% (normal), and 1.65% (high). Sera were analyzed for calcium, phosphorus, alkaline phosphatase, creatinine, blood urine nitrogen, 1,25-dihydroxyvitamin D, osteocalcin, tartrate-resistant acid phosphatase 5b, and fibroblast growth factor 23 (Fgf23). Femurs were evaluated by dual-energy x-ray absorptiometry, dynamic histomorphometry, and/or microcomputed tomography. Galnt3 knockout mice in C57BL/6J had the same biochemical phenotype observed in our previous study: hyperphosphatemia, inappropriately normal 1,25-dihydroxyvitamin D level, decreased alkaline phosphatase activity, and low intact Fgf23 concentration but high Fgf23 fragments. Skeletal analyses of their femurs revealed significantly high BMD with increased cortical bone area and trabecular bone volume. On all four phosphate diets, Galnt3 knockout mice had consistently higher phosphorus levels and lower alkaline phosphatase and intact Fgf23 concentrations than littermate controls. The low-phosphate diet normalized serum phosphorus, alkaline phosphatase, and areal BMD but failed to correct male infertility in Galnt3 knockout mice. The high-phosphate diet did not increase serum phosphorus concentration in either mutant or control mice due to a compensatory increase in circulating intact Fgf23 levels. In conclusion, dietary phosphate restriction normalizes biochemical and skeletal phenotypes of Galnt3 knockout mice and, thus, can be an effective therapy for tumoral calcinosis.

Corrosion of alloy 22 in phosphate ions effect and chloride containing solutions

International Nuclear Information System (INIS)

Carranza, Ricardo M.

2009-01-01

Alloy 22 belongs to Ni-Cr-Mo family. This alloy resists the most aggressive environments for industrial applications, in oxidizing as well as reducing conditions, because exhibits an excellent uniform and localized corrosion resistance in aqueous solution. Because of its outstanding corrosion resistant, this alloy is one of the candidate to be considered for the outer shell of the canister that would contain high level radioactive nuclear wastes in a geological repository. The aim of this work is to study ion phosphate influence over Alloy 22 corrosion behavior under aggressive conditions, such as high temperature and high ion chloride concentration, where this material might be susceptible to crevice corrosion. Two different types of samples were used: cylinder specimens for uniform corrosion behavior studies and Prismatic Crevice Assembly (PCA) specimens for localized corrosion studies. Electrochemical tests were performed in deaerated aqueous solution of 1 M NaCl and 1 M NaCl with different phosphate additions at 90 C degrees and pH near neutral. The anodic film and corrosion products obtained were studied by SEM/EDS. Cyclic Potentiodynamic Polarization (CPP) curves obtained for uniform corrosion studies, showed an increase of the passivity range in phosphate containing solutions. The passive current value was 1 μA/cm 2 approximately in all the tests. PCA electrochemical tests, that combined a CPP with a potentiostatic polarization step for 2 hours in between the forward and reverse scan, showed crevice corrosion development in some cases. The repassivation potential value, determined by the intersection of the forward and the reverse scan, increased with phosphate addition. A complete crevice corrosion inhibition effect was found for phosphate concentration higher than 0.3 M. These results indicate that the passivity potential range depend on phosphate presence and might be related with the incorporation of the anion in the passive film. Results of the tests

On the mechanism of ion exchange in zirconium phosphates

International Nuclear Information System (INIS)

Clearfield, A.; Kalnins, J.M.

1978-01-01

The exchange of transition metal (M 2+ ) ions from manganese through cobalt, nickel, copper to zinc with γ-zirconium phosphate was examined. By using acetate salts the hydrogen ion concentration is kept low enough to achieve high loadings. The fully loaded solids have the composition ZrM(PO 4 ) 2 .4H 2 O. Near quantitative uptakes are achieved at 100 0 C. The interlayer spacings change very little with loading indicating that γ-zirconium phosphate is able to accommodate cations and water molecules without appreciable increase in volume. The copper exchanged phase readily forms an acetylacetonate when shaken with 2,4-pentanedione. (author)

Metal Oxide Decomposition In Hydrothermal Alkaline Sodium Phosphate Solutions

Energy Technology Data Exchange (ETDEWEB)

S.E. Ziemniak

2003-09-24

Alkaline hydrothermal solutions of sodium orthophosphate (2.15 < Na/P < 2.75) are shown to decompose transition metal oxides into two families of sodium-metal ion-(hydroxy)phosphate compounds. Equilibria for these reactions are quantified by determining phosphate concentration-temperature thresholds for decomposition of five oxides in the series: Ti(IV), Cr(III), Fe(III, II), Ni(II) and Zn(II). By application of a computational chemistry method General Utility Lattice Program (GULP), it is demonstrated that the unique non-whole-number Na/P molar ratio of sodium ferric hydroxyphosphate is a consequence of its open-cage structure in which the H{sup +} and excess Na{sup +} ions are located.

Biomimetic fabrication of calcium phosphate/chitosan nanohybrid composite in modified simulated body fluids

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K. H. Park

2017-01-01

Full Text Available In this study, nucleation and growth of bone-like hydroxyapatite (HAp mineral in modified simulated body fluids (m-SBF were induced on chitosan (CS substrates, which were prepared by spin coating of chitosan on Ti substrate. The m-SBF showed a two fold increase in the concentrations of calcium and phosphate ions compared to SBF, and the post-NaOH treatment provided stabilization of the coatings. The calcium phosphate/chitosan composite prepared in m-SBF showed homogeneous distribution of approximately 350 nm-sized spherical clusters composed of octacalcium phosphate (OCP; Ca8H2(PO46·5H2O crystalline structure. Chitosan provided a control over the size of calcium phosphate prepared by immersion in m-SBF, and post-NaOH treatment supported the binding of calcium phosphate compound on the Ti surface. Post-NaOH treatment increased hydrophilicity and crystallinity of carbonate apatite, which increased its potential for biomedical application.

Variability of in vivo recovery of factor IX after infusion of monoclonal antibody purified factor IX concentrates in patients with hemophilia B. The Mononine Study Group.

Science.gov (United States)

White, G C; Shapiro, A D; Kurczynski, E M; Kim, H C; Bergman, G E

1995-05-01

Monoclonal antibody purified factor IX concentrate, Mononine (Armour Pharmaceutical Company, Kankakee, Illinois, USA), is a recently developed replacement factor concentrate for the treatment of patients with hemophilia B. The pharmacokinetic properties of monoclonal antibody purified factor IX concentrate (MAb Factor IX concentrate) have been evaluated in only small samples of patients, and little is known about those factors that might influenced in vivo recovery of factor IX after infusion is a larger patient population. In vivo recovery of factor IX was therefore evaluated for 80 different indications in 72 patients who received MAb Factor IX concentrate for the management of spontaneous or trauma-induced bleeding, or as prophylaxis with surgery. The average recovery after infusions for presurgical pharmacokinetic analysis (mean +/- standard deviation) was 1.28 +/- 0.56 U/dl rise per U/kg infused (range 0.41-2.80), and the average recovery after all infusions for treatment was 1.23 +/- 0.49 U/dl rise per U/kg infused (range - 0.35-2.92). Recovery values for multiple MAb Factor IX doses in a given patient were also variable; the average recovery was 1.22 +/- 0.53 U/dl rise per U/kg given, and standard deviations ranged from 0.03 to 1.26. Patient age, weight, and MAb Factor IX concentrate dose minimally but significantly influenced factor IX recovery. There was no significant effect of either race, history of previous thrombotic complications during treatment with other replacement factor concentrates, or bleeding state on recovery. All of the patients treated with this preparation experienced excellent hemostasis, and no thrombotic complications were observed.

Preparation of antibody coated tubes

International Nuclear Information System (INIS)

Robles Berrueta, A.M.

1997-01-01

Full text: 1. Purification of IgG: 2-4 ml serum at pH 8 with Buffer tris 1M pH 8. Let serum pass through the column of Sepharose Prot. A (1-2 ml). Wash with: a) Buffer tris 0.1M pH 8; b) Buffer tris 0.01M pH 8. Elute with Glycine 0.1M pH 3 adding eluant at 0.5 ml fractions and collect in eppendorf tubes containing 50μ1 Buffer tris 1M pH 8 to neutralize. 20 fractions are collected. Absorbency at 280nm is measured in each fraction. Pool is formed with protein factions. Dialysis against water is done during 48 hours changing water twice during that lapse. Regenerate column for future use with 1 wash Urea 2M, second with LiCl 1M and third wash with Glycine 0.1 M pH 2.5. 2. Antibody Immobilization on an Activated Solid Phase: NUNC maxisorp, Star tube 75x12 mm is trade mark for polystyrene tubes from Pharmacia with less than 5% CV% inhomogeneity in adsorption of IgG and less than 10% for random bias of any result from mean value. They are kept closed until use. They are not reusable. The antibody is diluted to a working dilution with buffer carbonate-bi carbonate 0.1M, pH 9.6 (BCBic). Adequate volume is pipetted into maxisorb NUNC tubes paying attention not to produce droplets (1/200 dilution and 0.3 ml/tube are used for TSH assays). An incubation overnight is enough to get maximum IgG binding. Antibody solution is recovered for further use (after mixing with additional antibody). Solid phase is subject to washing with phosphate buffer with non-Ionic detergent (1 ml PB.5 + 0.5% Tween 20) and then with pure water. Tubes are left two hours upside down and kept tightly closed with dissicant at - 20 deg. C

Measurements of natural radioactivity in phosphate fertilizers

International Nuclear Information System (INIS)

Ioannides, K.G.; Mertzimekis, T.J.; Papachristodoulou, C.A.; Tzialla, C.E.

1997-01-01

The natural radioactivity, mainly due to radium ( 226 Ra), in phosphate fertilizers used in north-western Greece has been measured by γ-spectroscopy. Also radioactivity measurements were performed in soil samples and were compared to samples from undisturbed soils. 226 Ra belongs to the 238 U chain and is the precursor of radon gas ( 222 Rn). The radon concentrations in warehouses, where large quantities of fertilizers are kept, were measured with CR-39 SSNTDs. The radium concentrations in the fertilizers ranged from 0 to 4584 Bq kg -1 and the radon concentrations in warehouses were measured 540-3320 Bq m -3 . The results are discussed from the radiation protection point of view

Determination of tricresyl phosphate air contamination in aircraft.

Science.gov (United States)

Denola, G; Hanhela, P J; Mazurek, W

2011-08-01

Monitoring of tricresyl phosphate (TCP) contamination of cockpit air was undertaken in three types of military aircraft [fighter trainer (FT), fighter bomber (FB), and cargo transport (CT) aircraft]. The aircraft had a previous history of pilot complaints about cockpit air contamination suspected to originate from the engine bleed air supply through the entry of aircraft turbine engine oil (ATO) into the engine compressor. Air samples were collected in flight and on the ground during engine runs using sorbent tubes packed with Porapak Q and cellulose filters. A total of 78 air samples were analysed, from 46 different aircraft, and 48 samples were found to be below the limit of detection. Nine incidents of smoke/odour were identified during the study. The concentrations of toxic o-cresyl phosphate isomers were below the level of detection in all samples. The highest total TCP concentration was 51.3 μg m(-3), while most were generally found to be contamination of cabin/cockpit air has been the subject of much concern in aviation, quantitative data are sparse.

ANA (Antinuclear Antibody Test)

Science.gov (United States)

... as ratios. For example, the result 1:320 means that one part blood sample was mixed with 320 parts of a diluting ... name "antinuclear". My doctor told me my ANA test is ... normal concentration of these antibodies. This is one of the tools in diagnosing lupus as well ...

Phosphated minerals to be used as radioactive reference materials

International Nuclear Information System (INIS)

Braganca, M.J.C.S.; Tauhata, L.; Clain, A.F.; Moreira, I.

2003-01-01

The production and the supplying of certified reference materials, or deliberated contaminated materials containing natural radionuclides for laboratories which analyses environmental samples are fundamentals for the correct measurements of their radioactive levels. This analysis quality represents a important step for the safeguards of the population health, and quality control of the imported and exported products, such as minerals, agricultural and raw materials. The phosphate rocks, containing significant concentrations of thorium, and used as raw material and fertilizers justified a study for better characterization and distinction to be used cas certified reference radioactive materials. Therefore, samples from the two carboanalytical-alkaline chimneys (Araxa and Catalao), and one from metasedimentar origin (Patos de Minas), distant 100 km from each other, were collected and chemical and cholecystographic characterized by optical emission, X-ray diffraction and fluorescence. The element concentrations were determined by neutron activation analysis, ICP-MS and ICP-AES. The results, after multivariate statistical analysis and study of correlations among elements, have shown geochemical similarities of the phosphates from Araxa and Catalao, and differences from Patos de Minas, despite of the geographic proximity. The concentration of thorium between 200 and 500 (mg/g) allows to use such minerals as reference materials

Performance of pineapple slips inoculated with diazotrophic phosphate-solubilizing bacteria and rock phosphate

Directory of Open Access Journals (Sweden)

Lílian Estrela Borges Baldotto

2014-06-01

Full Text Available Besides fixing N2, some diazotrophic bacteria or diazotrophs, also synthesize organic acids and are able to solubilize rock phosphates, increasing the availability of P for plants. The application of these bacteria to pineapple leaf axils in combination with rock phosphate could increase N and P availability for the crop, due to the bacterial activity of biological nitrogen fixation and phosphate solubilization. The objectives of this study were: (i to select and characterize diazotrophs able to solubilize phosphates in vitro and (ii evaluate the initial performance of the pineapple cultivars Imperial and Pérola in response to inoculation with selected bacteria in combination with rock phosphate. The experiments were conducted at Universidade Estadual do Norte Fluminense Darcy Ribeiro, in 2009. In the treatments with bacteria the leaf contents of N, P and K were higher than those of the controls, followed by an increase in plant growth. These results indicate that the combined application of diazotrophic phosphate-solubilizing bacteria Burkholderia together with Araxá rock phosphate can be used to improve the initial performance of pineapple slips.

Evaluation of in situ capping with clean soils to control phosphate release from sediments

Energy Technology Data Exchange (ETDEWEB)

Xu, Di [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China); Ding, Shiming, E-mail: smding@niglas.ac.cn [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China); Sun, Qin [College of Environmental Science and Engineering, Hohai University, Nanjing (China); Zhong, Jicheng [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China); Wu, Wei; Jia, Fei [College of Environmental Science and Engineering, Hohai University, Nanjing (China)

2012-11-01

Evaluation of in situ capping with clean soils to control phosphate release from the sediments of a eutrophic bay in Lake Taihu was performed after 18 months of capping. The concentrations of dissolved reactive phosphate (DRP) in pore waters and DRP resupply from native sediments and capped sediments were determined using high-resolution dialysis (HR-Peeper) and a Zr-oxide diffusive gradients in thin films (Zr-oxide DGT) technique. The adsorption isotherm of these sediments was further investigated using a modified Langmuir model. The results showed low concentrations of DRP in pore waters with a low resupply from the sediments for sustaining pore water DRP concentration after capping. The calculated flux to the overlying water following the capping treatment was approximately half of that for the native sediments, implying that the capping reduced the release of phosphate from the sediments. The low resupply of the sediments after capping was further demonstrated by larger partitioning coefficient (K{sub p}) values and greater adsorption capacity (Q{sub max}) values, while zero equilibrium concentrations (EPC{sub 0}s) were similar to those in native sediments. The larger K{sub p} and Q{sub max} were attributed to higher active Fe and Al introduced by the capping, indicating that the binding of phosphate onto the active Fe and Al played a critical role in reducing the internal loading of phosphorous. Highlights: Black-Right-Pointing-Pointer Evaluation of capping with soils was performed through high-resolution sampling. Black-Right-Pointing-Pointer Capping decreased the concentrations of DRP in pore waters and its release to waters. Black-Right-Pointing-Pointer Capping decreased the resupply of pore water DRP from the sediments. Black-Right-Pointing-Pointer Capped sediments had stronger abilities to adsorb and retain P. Black-Right-Pointing-Pointer Active Fe and Al introduced by capping played a critical role.

Evaluation of in situ capping with clean soils to control phosphate release from sediments

International Nuclear Information System (INIS)

Xu, Di; Ding, Shiming; Sun, Qin; Zhong, Jicheng; Wu, Wei; Jia, Fei

2012-01-01

Evaluation of in situ capping with clean soils to control phosphate release from the sediments of a eutrophic bay in Lake Taihu was performed after 18 months of capping. The concentrations of dissolved reactive phosphate (DRP) in pore waters and DRP resupply from native sediments and capped sediments were determined using high-resolution dialysis (HR-Peeper) and a Zr-oxide diffusive gradients in thin films (Zr-oxide DGT) technique. The adsorption isotherm of these sediments was further investigated using a modified Langmuir model. The results showed low concentrations of DRP in pore waters with a low resupply from the sediments for sustaining pore water DRP concentration after capping. The calculated flux to the overlying water following the capping treatment was approximately half of that for the native sediments, implying that the capping reduced the release of phosphate from the sediments. The low resupply of the sediments after capping was further demonstrated by larger partitioning coefficient (K p ) values and greater adsorption capacity (Q max ) values, while zero equilibrium concentrations (EPC 0 s) were similar to those in native sediments. The larger K p and Q max were attributed to higher active Fe and Al introduced by the capping, indicating that the binding of phosphate onto the active Fe and Al played a critical role in reducing the internal loading of phosphorous. Highlights: ► Evaluation of capping with soils was performed through high-resolution sampling. ► Capping decreased the concentrations of DRP in pore waters and its release to waters. ► Capping decreased the resupply of pore water DRP from the sediments. ► Capped sediments had stronger abilities to adsorb and retain P. ► Active Fe and Al introduced by capping played a critical role.

Radioactivity of Ore Sites of Lead, Zinc and Phosphate in Serbia

International Nuclear Information System (INIS)

Todorovic, D.; Jankovic, M.; Nikolic, J.; Kosutic, D.

2011-01-01

Natural resources such as ores contain radioactive nuclides at various concentrations. Therefore it is important to investigate the radioactivity in these resources as well as in the soil at the locations of ore deposits. For that reason we conducted preliminary measurements in the soil samples taken from the locations of lead and zinc ore deposits (Bosilegrad and Raska) and from the locations of phosphate ore deposits of phosphate (Bosilegrad). The activity concentrations of radionuclides in soil samples were determined by gamma spectrometry (HPGe detector, relative efficiency 23 %). Results showed the presence of natural radionuclides 226Ra, 232Th, 40K, 235U, 238U as well as the produced radionuclide 137Cs (from the Chernobyl accident). Ambient gamma radiation dose rate in ground level air was also measured. (author)

Clinical usefulness of scintigraphy with 99mTechnetium phosphates in rhabdomyolysis

International Nuclear Information System (INIS)

Aizawa, Nobuyuki; Hara, Yoshikuni; Suzuki, Yutaka; Akashi, Tsunehiro; Kamei, Tetsumasa; Uchiyama, Fujio; Mitsui, Tamito; Yamazaki, Yuki.

1990-01-01

We performed bone scans with 99m Technetium phosphates in 15 cases of clinically suspected rhabdomyolysis admitted to Chigasaki Tokushukai Hospital. Whole body scans were performed within 5 days from the onset of illness or admission. Accumulation of the radioactivity in the skeletal muscle was revealed in 13 of the 15 cases and the involved muscle groups were visualized vividly. Etiologies of rhabdomyolysis were diverse, ranging from malignant syndrome to sepsis. Myocardial concentration was absent in all of the cases. Renal concentration of the isotope was seen in cases where the degree of rhabdomyolysis was higher and renal impairment was present. We conclude that 99m Technetium phosphate bone scan is useful in clinically suspected rhabdomyolysis as a diagnostic test and as a test to localize and quantitate the muscular involvement. (author)

How do arbuscular mycorrhizal fungi handle phosphate? New insight into fine-tuning of phosphate metabolism.

Science.gov (United States)

Ezawa, Tatsuhiro; Saito, Katsuharu

2018-04-27

Contents Summary I. Introduction II. Foraging for phosphate III. Fine-tuning of phosphate homeostasis IV. The frontiers: phosphate translocation and export V. Conclusions and outlook Acknowledgements References SUMMARY: Arbuscular mycorrhizal fungi form symbiotic associations with most land plants and deliver mineral nutrients, in particular phosphate, to the host. Therefore, understanding the mechanisms of phosphate acquisition and delivery in the fungi is critical for full appreciation of the mutualism in this association. Here, we provide updates on physical, chemical, and biological strategies of the fungi for phosphate acquisition, including interactions with phosphate-solubilizing bacteria, and those on the regulatory mechanisms of phosphate homeostasis based on resurveys of published genome sequences and a transcriptome with reference to the latest findings in a model fungus. For the mechanisms underlying phosphate translocation and export to the host, which are major research frontiers in this field, not only recent advances but also testable hypotheses are proposed. Lastly, we briefly discuss applicability of the latest tools to gene silencing in the fungi, which will be breakthrough techniques for comprehensive understanding of the molecular basis of fungal phosphate metabolism. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Opalescence in monoclonal antibody solutions and its correlation with intermolecular interactions in dilute and concentrated solutions.

Science.gov (United States)

Raut, Ashlesha S; Kalonia, Devendra S

2015-04-01

Opalescence indicates physical instability of a formulation because of the presence of aggregates or liquid-liquid phase separation in solution and has been reported for monoclonal antibody (mAb) formulations. Increased solution opalescence can be attributed to attractive protein-protein interactions (PPIs). Techniques including light scattering, AUC, or membrane osmometry are routinely employed to measure PPIs in dilute solutions, whereas opalescence is seen at relatively higher concentrations, where both long- and short-range forces contribute to overall PPIs. The mAb molecule studied here shows a unique property of high opalescence because of liquid-liquid phase separation. In this study, opalescence measurements are correlated to PPIs measured in diluted and concentrated solutions using light scattering (kD ) and high-frequency rheology (G'), respectively. Charges on the molecules were calculated using zeta potential measurements. Results indicate that high opalescence and phase separation are a result of the attractive interactions in solution; however, the presence of attractive interactions do not always imply phase separation. Temperature dependence of opalescence suggests that thermodynamic contribution to opalescence is significant and Tcloud can be utilized as a potential tool to assess attractive interactions in solution. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

Characterization, Leaching, and Filtration Testing for Bismuth Phosphate Sludge (Group 1) and Bismuth Phosphate Saltcake (Group 2) Actual Waste Sample Composites

International Nuclear Information System (INIS)

Lumetta, Gregg J.; Buck, Edgar C.; Daniel, Richard C.; Draper, Kathryn; Edwards, Matthew K.; Fiskum, Sandra K.; Hallen, Richard T.; Jagoda, Lynette K.; Jenson, Evan D.; Kozelisky, Anne E.; MacFarlan, Paul J.; Peterson, Reid A.; Shimskey, Rick W.; Sinkov, Sergey I.; Snow, Lanee A.

2009-01-01

A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan.() The test program was subdivided into logical increments. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. The actual waste-testing program included homogenizing the samples by group, characterizing the solids and aqueous phases, and performing parametric leaching tests. Two of the eight defined groups - bismuth phosphate sludge (Group 1) and bismuth phosphate saltcake (Group 2) - are the subjects of this report. The Group 1 waste was anticipated to be high in phosphorus and was implicitly assumed to be present as BiPO4 (however, results presented here indicate that the phosphate in Group 1 is actually present as amorphous iron(III) phosphate). The Group 2 waste was also anticipated to be high in phosphorus, but because of the relatively low bismuth content and higher aluminum content, it was anticipated that the Group 2 waste would contain a mixture of gibbsite, sodium phosphate, and aluminum phosphate. Thus, the focus of the Group 1 testing was on determining the behavior of P removal during caustic leaching, and the focus of the Group 2 testing was on the removal of both P and Al. The waste-type definition, archived sample conditions, homogenization activities, characterization (physical, chemical, radioisotope, and crystal habit), and caustic leaching behavior as functions of time, temperature, and hydroxide concentration are discussed in this report. Testing was conducted according to TP-RPP-WTP-467

Kinetics of dissolution of calcium phosphate (Ca-P bioceramics

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Lukas Brazda

2008-06-01

Full Text Available Hydroxyapatite (HAp and β-tricalcium phosphate (β-TCP are widely used bioceramics for surgical or dental applications. This paper is dealing with dissolution kinetics of synthetically prepared β-TCP and four types of HAp granules. Two groups of HAp, treated at different temperatures, each of them with two different granule sizes, were tested. Three corrosive solutions with different pH and simulated body fluid (SBF were used for immersing of the samples. Changes in concentrations of calcium and phosphate ions, pH level and weight changes of the samples were observed. It was found that presence of TRIS buffer enhanced dissolution rate of the β-TCP approximately two times. When exposed to SBF solution, calcium phosphate (most probably hydroxyapatite precipitation predominates over β-TCP dissolution. Results from HAp samples dissolution showed some unexpected findings. Neither heat treatment nor HAp particle size made any major differences in dissolution rate of the same mass of each HAp sample.

The Effect of Induced Antibodies with Respect to Neutralization, Clearance Rate and Functional Activity in a Rabbit/Infliximab Model

DEFF Research Database (Denmark)

Henriksen, Maiken Lumby; Søgaard Teisner, Ane; Kjeldsen, Jens

2016-01-01

BACKGROUND: Therapeutic antibodies are a developing field for treatment of an expanding number of inflammatory diseases, including Crohn's disease. Treatment with monoclonal antibodies is frequently hampered by development of anti-drug antibodies (ADAs) that may compromise the treatment. MATERIALS...... AND METHODS: We addressed this issue in a rabbit model of treatment with the anti-tumor-necrosis factor alpha (TNFα) antibody, infliximab (IFX). We developed an inhibition ELISA to selectively measure absolute concentrations of neutralizing antibodies and another ELISA for measuring the concentration...... of functional IFX in the circulation. RESULTS: We found that the concentration of functional IFX was inversely proportional to the concentration of neutralizing antibodies. CONCLUSION: Administration of IFX to rabbits showed diversity in immune responses/tolerance toward IFX, corresponding to responses observed...

Kinetics Modeling and Isotherms for Adsorption of Phosphate from Aqueous Solution by Modified Clinoptilolit

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Mohammad Malakootian

2012-01-01

Full Text Available The Phosphorous discharge into the surface water led to excessive growth of algae and eutrophication in lakes and rivers. Therefore the phosphorus removal is important due to negative effect on water resources. The aim of this study was to investigat the modification of clinoptilolite and application of modified clinoptilolite for phosphorous adsorption from aqueous solution and isotherms and kinetics modeling. Hexadecyl Trimethyl Ammonium bromide (HDTMA-Br, Hexadecyl trimethyl Ammonium Chloride (HDTMA-Cl, Sodium Decyl Sulphate (SDS and Cetrimide-C were used for modification of clinoptilolite. Experiments were conducted using jar apparatus and batch system. The effect of pH, adsorbent doses, contact time, phosphate initial concentration and particle size were studied surveyed on phosphate adsorption by modified clinoptilolite. The most common isotherms and the kinetics adsorption equations were used for determination of adsorption rate and dynamic reaction. The results showed that maximum phosphate adsorption was obtained in the pH of 7 and contact time 90min. Also it was found with the increasing of phosphate initial concentration, phosphate removal efficiency decreased significantly. Langmuir No 2 showed a good correlation compared to other isotherms (R2=0.997. Maximum adsorption capacity was obtained in 20g/L adsorbent dose (22.73mg/g. Also Interaparticle diffusion kinetics well fits with experimental data (R2=0.999 with constant rate of 3.84mg/g min0.5. The result showed that modified clinoptilolite can be used successfully as low cost and effective absorbent for phosphate removal.

Does vaccination ensure protection? Assessing diphtheria and tetanus antibody levels in a population of healthy children

Science.gov (United States)

Gowin, Ewelina; Wysocki, Jacek; Kałużna, Ewelina; Świątek-Kościelna, Bogna; Wysocka-Leszczyńska, Joanna; Michalak, Michał; Januszkiewicz-Lewandowska, Danuta

2016-01-01

Abstract Vaccination effectiveness is proven when the disease does not develop after a patient is exposed to the pathogen. In the case of rare diseases, vaccination effectiveness is assessed by monitoring specific antibody levels in the population. Such recurrent analyses allow the evaluation of vaccination programs. The primary schedule of diphtheria and tetanus vaccinations is similar in various countries, with differences mainly in the number and timing of booster doses. The aim of the study was to assess diphtheria and tetanus antibody concentrations in a population of healthy children. Diphtheria and tetanus antibody levels were analyzed in a group of 324 children aged 18 to 180 months. All children were vaccinated in accordance with the Polish vaccination schedule. Specific antibody concentrations greater than 0.1 IU/mL were considered protective against tetanus or diphtheria. Levels above 1.0 were considered to ensure long-term protection. Protective levels of diphtheria antibodies were found in 229 patients (70.46%), and of tetanus in 306 patients (94.15%). Statistically significant differences were found in tetanus antibody levels in different age groups. Mean concentrations and the percentage of children with high tetanus antibody titers increased with age. No similar correlation was found for diphtheria antibodies. High diphtheria antibody levels co-occurred in 72% of the children with high tetanus antibody levels; 95% of the children with low tetanus antibody levels had low levels of diphtheria antibodies. The percentage of children with protective diphtheria antibody levels is lower than that in the case of tetanus antibodies, both in Poland and abroad, but the high proportion of children without diphtheria protection in Poland is an exception. This is all the more puzzling when taking into account that Polish children are administered a total of 5 doses containing a high concentration of diphtheria toxoid, at intervals shorter than 5 years. The

Measurement of "2"2"6Ra and "2"2"8Ra in Brazilian and Israeli Phosphates

International Nuclear Information System (INIS)

Ferreira, W.; Canella Avelar, A.; Menezes, M.

2014-01-01

Since the 1970s, the IAEA recognizes that phosphoric acid presents an alternate source of uranium, but given the status of both phosphate and uranium markets the potential of recovering uranium from phosphoric acid still marginal. New technologies for the recovery of uranium from phosphoric acid, national and global interests and environment barriers could shape this market in the medium and long-term scenarios. On the other hand, the use of phosphates is the major source of phosphorus in agriculture and livestock. Beyond phosphorus and calcium, phosphate is also source of some hazardous elements, such: arsenic, cadmium, thorium and uranium, including a variety of radioisotopes as well. This radioactivity is sure to be released in the environment, contributing to the background. The risk is not recognized for some of the players in this market, mainly workers who apply phosphate fertilizers in the farmland, in some cases manipulating phosphates with their bare hands, and without any respiratory protection equipment (RPE) as well. This paper deals with the radioactivity from "2"2"6Ra and "2"2"8Ra in four phosphates often used in Brazilian agriculture. Three Brazilian and an Israeli phosphate were analysed and compared with international criteria. The specific activities of "2"2"6Ra (from the uranium decay series) and "2"2"8Ra (from the thorium decay series) were taken into consideration to ensure an adequate risk assessment. Specific activities were determined by high-resolution gamma spectroscopy with germanium detector and Genie® software from Canberra in the Centre of Nuclear Technology Development (CDTN/CNEN). The concentration of "2"2"6Ra was measured using the 186.2 keV energy peak, the concentration of "2"2"8Ra through "2"2"8Ac. The system was calibrated using a set of standard materials from IAEA. The measured samples were crushed and sieved to a grain (98% at least) size as small as 75 μm. Stable mass was achieved grinding, drying at 105°C and mixing

Integrated assessment of the phosphate industry

International Nuclear Information System (INIS)

Ryan, M.T.; Cotter, S.J.

1980-05-01

The phosphate industry in the United States includes three major activities, namely, mining and milling of phosphate rock, phosphate product manufacture, and phosphate product use. Phosphatic materials contain uranium, thorium, and their decay products in greater than background amounts. This assessment of the radiological impacts associated with the redistribution of radioactive components of phosphate materials may provide insight into the effects of uranium extraction from phosphate materials for use in the nuclear fuel cycle

Phosphatized algal-bacterial assemblages in Late Cretaceous phosphorites of the Voronezh Anteclise

Science.gov (United States)

Maleonkina, Svetlana Y.

2003-01-01

Late Cretaceous phosphogenesis of the Voronezh Anteclise has occurred during Cenomanian and Early Campanian. SEM studies show the presence of phosphatized algal-bacterial assemblages both in Cenomanian and Campanian phosphorites. In some Cenomanian nodular phosphorite samples revealed empty tubes 1 - 5 microns in diameter, which are most likely trichomes of cyanobacterial filaments. Other samples contained accumulations of spheres 0,5-3 microns, similar to coccoidal bacteria. Complicated tubular forms with variable diameter 2 - 5 microns occur on surface of some quartz grains in nodules. They are probably pseudomorphs after algae. We found similar formations in the Campanian phosphate grains. Frequently, grain represents a cyanobacterial mat, which is sometimes concentrically coated by phosphatic films. The films of some grains retain the primary structure, their concentric layers are formed by pseudomorphs after different bacterial types and obviously they represent oncolite. In other cases, the primary structure is unobservable because of recrystallization process erases them. Occasionally, the central part retains the coccoidal structure and the recrystallization affects only films. Besides the core of such oncolite can be represented not only by phosphatic grain, but also by grains of other minerals, such as quartz, glauconite and heavy minerals, which serve as a substrate for cyanobacterial colonies. Bacteria also could settle on cavity surfaces and interiors frames of sponge fragments, teeth and bones.

Optimizing conditions for calcium phosphate mediated transient transfection

Directory of Open Access Journals (Sweden)

Ling Guo

2017-03-01

Conclusions: Calcium phosphate mediated transfection is the most low-cost approach to introduce recombinant DNA into culture cells. However, the utility of this procedure is limited in highly-differentiated cells. Here we describe the specific HBS-buffered saline, PH, glycerol shock, vortex strength, transfection medium, and particle concentrations conditions necessary to optimize this transfection method in highly differentiated cells.

Characterization and bioremediation potential of phosphate solubilizing bacteria isolated from tunisian phosphogypsum

International Nuclear Information System (INIS)

Trifi, Houda

2011-01-01

Phosphorus bioavailability is often limited in agricultural soils. In this work, two bacteria were isolated from Tunisian phosphogypsum (PG). These ones have the capacity to dissolve inorganic phosphate (CaHPO 4 and Ca 3 (PO 4 ) 2 ). This capacity is determined by the clear halo formation around colonies in NBRIP agar medium. To confirm the solubilization phenotype, the concentration of solubilized phosphate by isolates cultivated in NBRIP broth containing PG was measured. These two bacteria noted BRM17 and BRM18 are identified as Pantoea sp. and Pseudomonas sp, respectively. The results show that BRM17 solubilizes about 2 times more phosphate in broth NBRIP medium after 48 hours of incubation than BRM18. Tunisian phosphogypsum contains 1100 ppm of strontium (Sr). Sr toxicity on bacteria was determined by concentration that gives half-maximal inhibition of bacteria (IC 50 ). Compared with Cupriavidus metallidurans (bacteria tolerant to most of heavy metals), BRM17 and BRM18 cultivated in broth medium containing increasing concentrations of Sr were found tolerant to Sr. The potential of bioremediation is tested by the rate evaluation of Sr adsorption by these bacteria. The results show the high ability of BRM18 to adsorb Sr. The resistance of isolates to ionizing radiation is also determined by the exposure of bacterial cultures to various doses of gamma radiation. BRM17 is considered radioresistant while BRM18 is radiosensitive. The effect on seed germination of wheat and pea inoculated with bacteria was tested. No positive effect was detected. This study is considered with the use of BRM17 and BRM18 in a bioremediation process and the improvement of phosphate uptake by plants cultivated in polluted environments.

Sorption and desorption of glyphosate, MCPA and tetracycline and their mixtures in soil as influenced by phosphate.

Science.gov (United States)

Munira, Sirajum; Farenhorst, Annemieke

2017-12-02

Phosphate fertilizers and herbicides such as glyphosate and MCPA are commonly applied to agricultural land, and antibiotics such as tetracycline have been detected in soils following the application of livestock manures and biosolids to agricultural land. Utilizing a range of batch equilibrium experiments, this research examined the competitive sorption interactions of these chemicals in soil. Soil samples (0-15 cm) collected from long-term experimental plots contained Olsen P concentrations in the typical (13 to 20 mg kg -1 ) and elevated (81 to 99 mg kg -1 ) range of build-up phosphate in agricultural soils. The elevated Olsen P concentrations in field soils significantly reduced glyphosate sorption up to 50%, but had no significant impact on MCPA and tetracycline sorption. Fresh phosphate additions in the laboratory, introduced to soil prior to, or at the same time with the other chemical applications, had a greater impact on reducing glyphosate sorption (up to 45%) than on reducing tetracycline (up to 13%) and MCPA (up to 8%) sorption. The impact of fresh phosphate additions on the desorption of these three chemicals was also statistically significant, but numerically very small namely glyphosate and tetracycline and 3% for MCPA. The presence of MCPA significantly reduced sorption and increased desorption of glyphosate, but only when MCPA was present at concentrations much greater than environmentally relevant and there was no phosphate added to the MCPA solution. Tetracycline addition had no significant effect on glyphosate sorption and desorption in soil. For the four chemicals studied, we conclude that when mixtures of phosphate, herbicides and antibiotics are present in soil, the greatest influence of their competitive interactions is phosphate decreasing glyphosate sorption and the presence of phosphate in solution lessens the potential impact of MCPA on glyphosate sorption. The presence of chemical mixtures in soil solution has an overall greater impact

Monoclonal antibodies: potential role in radiation therapy and oncology

International Nuclear Information System (INIS)

Order, S.E.

1982-01-01

Specificity, which is a hallmark of the immune system, will be used in radiation oncology in both diagnosis and therapy through the application of radiolabelled monoclonal and polyclonal antibodies. Antigenic specificities, antibody preparations, and the tumor as a target for radiolabelled antibody is reviewed. Several clinical situations, i.e. single tumor cell suspensions, intraperitoneal single cells and masses, and solid tumors are reviewed in regard to both immune antibody targeting and specific differences between tumors in these regions. The concentration of tumor associated antigens is introductory to radiolabelled antibodies in diagnosis. In the radiation therapy of solid tumors, data regarding tumor dose, tumor effective half-life, varied antibody preparations, and the use of radiolabelled antibody as a method of tumor implantation is discussed using antiferritin 131 I-IgG as a model in hepatoma. The theoretical applications of monoclonal antibody integrated in cancer therapy are then presented as a new goal for future development

Basic studies on the tumor imaging using antibodies to human alpha-fetoprotein

International Nuclear Information System (INIS)

Sakahara, Harumi; Endo, Keigo; Nakashima, Tetsuo; Ohta, Hitoya; Torizuka, Kanji

1984-01-01

Using polyclonal antibodies to human α-fetoprotein (AFP), the effect of iodination on the antibody activity and tumor accumulation of radioiodinated antibodies in tumor bearing nude mice were examined. Antibodies, obtained from horse antiserum and purified by affinity chromatography, were iodinated by the chloramine-T method and their antibody activity was evaluated using RIA and Scatchard plot analysis. When high concentrations of chloramine-T were used or more than 2.6 iodine atoms were incorporated per antibody molecule, the antigen binding capacity rather than the affinity constant was affected by the iodination. The antibody activity was completely destroyed at an iodine to antibody molar ratio of 15.4. Antibodies, however, which were iodinated under low concentrations of chloramine-T and contained less than 0.8 iodines per antibody molecule, showed almost full retention of their antibody activity. Nude mice transplanted with AFP producing human testicular tumor or AFP non-producing human urinary bladder tumor were administered intravenously with 131 I-labeled antibodies to human AFP. Scintigrams were taken at 1, 2, 4 and 7 days after the injection of labeled antibodies. At day 7, nude mice were sacrificed and organs and tumor were removed, weighed and counted. In nude mice bearing testicular tumor, tumor image became gradually clear with decreasing background activity and tumor to blood ratio, obtained, was 0.82 for testicular tumor compared to 0.42 for bladder tumor. These results indicated a specific in vivo localization of 131 I-labeled antihuman AFP antibodies in AFP producing tumor. (author)

Effects of education on low-phosphate diet and phosphate binder intake to control serum phosphate among maintenance hemodialysis patients: A randomized controlled trial

Directory of Open Access Journals (Sweden)

Eunsoo Lim

2018-03-01

Full Text Available Background : For phosphate control, patient education is essential due to the limited clearance of phosphate by dialysis. However, well-designed randomized controlled trials about dietary and phosphate binder education have been scarce. Methods : We enrolled maintenance hemodialysis patients and randomized them into an education group (n = 48 or a control group (n = 22. We assessed the patients' drug compliance and their knowledge about the phosphate binder using a questionnaire. Results : The primary goal was to increase the number of patients who reached a calcium-phosphorus product of lower than 55. In the education group, 36 (75.0% patients achieved the primary goal, as compared with 16 (72.7% in the control group (P = 0.430. The education increased the proportion of patients who properly took the phosphate binder (22.9% vs. 3.5%, P = 0.087, but not to statistical significance. Education did not affect the amount of dietary phosphate intake per body weight (education vs. control: -1.18 ± 3.54 vs. -0.88 ± 2.04 mg/kg, P = 0.851. However, the dietary phosphate-to-protein ratio tended to be lower in the education group (-0.64 ± 2.04 vs. 0.65 ± 3.55, P = 0.193. The education on phosphate restriction affected neither the Patient-Generated Subjective Global Assessment score (0.17 ± 4.58 vs. -0.86 ± 3.86, P = 0.363 nor the level of dietary protein intake (-0.03 ± 0.33 vs. -0.09 ± 0.18, P = 0.569. Conclusion : Education did not affect the calcium-phosphate product. Education on the proper timing of phosphate binder intake and the dietary phosphate-to-protein ratio showed marginal efficacy.

Effect of radiative trapping on measurement of the spectroscopic properties of Yb sup 3 sup + :phosphate glasses

CERN Document Server

Dai Shi Xun; Wen Lei; Hu Li Li; Jiang Zhong Hon

2003-01-01

The effect of radiative trapping on measurement of the spectroscopic properties of Yb sup 3 sup + -doped phosphate glasses was investigated as a function of Yb sup 3 sup + concentration at different thicknesses. It was found that radiative trapping exists generally in Yb sup 3 sup + :phosphate glasses, even at low concentration. As a result, the measured lifetime of Yb sup 3 sup + in phosphate glasses is usually larger than the calculated one. The maximum discrepancies between them at high concentration are found to be <42%. The calculated lifetime should be used as a reference in determining the true value of the measured lifetime because of it being lengthened largely by radiative trapping. On the other hand, the shape of fluorescence spectrum exhibits remarkable changes due to the radiative trapping. What is more, the intensity increase of DELTA lambda sub e sub f sub f at high concentration is greater than that of low doping. The DELTA lambda sub e sub f sub f increases 36% from 53 to 72 nm with thickn...

Development and evaluation of a simple, direct, solid-phase radioimmunoassay of serum cortisol from readily available reagents

International Nuclear Information System (INIS)

McConway, M.G.; Chapman, R.S.

1986-01-01

A simple, rapid solid-phase radioimmunoassay for serum cortisol was developed using cortisol antibody and commercially available radioiodinated cortisol ligand. The assay involves a 1-h incubation at ambient temperature, using the antibody covalently linked by the easily performed carbonyldiimidazole method, to microcrystalline cellulose. A detailed comparison of the accepted 0.125 mol/l citrate, pH 4.0, and an alternative 0.1 mol/l phosphate/8-anilinonaphthalene sulphonic acid, pH 7.4, diluent demonstrated similar precision and recovery. Phosphate, pH 7.4 diluent was adopted as the diluent of choice, since it was economical of antibody and maintained good precision over a wider working range of cortisol concentration. (Auth.)

The Australian national reactive phosphate rock project - Aims, experimental approach, and site characteristics

International Nuclear Information System (INIS)

McLaughlin, M.J.

2002-01-01

Field-based cutting trials were established across Australia in a range of environments to evaluate the agronomic effectiveness of 5 phosphate rocks, and 1 partially acidulated phosphate rock, relative to either single super-phosphate or triple superphosphate. The phosphate rocks differed in reactivity, as determined by the degree of carbonate substitution for phosphate in the apatite structure and solubility of phosphorus present in the fertilizers in 2% formic acid, 2% citric acid and neutral ammonium citrate. Sechura (Bayovar) and North Carolina phosphate rocks were highly reactive (>70% solubility in 2% formic acid), whilst Khouribja (Moroccan) and Hamrawein (Egypt) phosphate rock were moderately reactive. Duchess phosphate rock from Queensland was relatively unreactive ( 2 , from 4.0 to 5.1, and Colwell extractable phosphorus ranged from 3 to 47 μg/g prior to fertilizer application. Two core experiments were established at each site. The first measured the effects of phosphate rock reactivity on agronomic effectiveness, while the second core experiment measured the effects of the degree of water solubility of the phosphorus source on agronomic effectiveness. The National Reactive Phosphate Rock Project trials provided the opportunity to confirm the suitability of accepted procedures to model fertilizer response and to develop new approaches for comparing different fertilizer responses. The Project also provided the framework for subsidiary studies such as the effect of fertilizer source on soil phosphorus extractability; cadmium and fluorine concentrations in herbage; evaluation of soil phosphorus tests; and the influence of particle size on phosphate rock effectiveness. The National Reactive Phosphate Rock Project presents a valuable model for a large, Australia-wide, collaborative team approach to an important agricultural issue. The use of standard and consistent experimental methodologies at every site ensured that maximum benefit was obtained from data

Bioavailability of radionuclides 226Ra, 228Ra and 210Pb present in the brazilian phosphate fertilizers and phosphogypsum

International Nuclear Information System (INIS)

Russo, Ana Carolina

2013-01-01

Phosphogypsum, also called gypsum, by-product of the phosphate fertilizer industry, can be used as soil conditioner since it provides improvements in the soil-plant system. However, this by-product concentrates radionuclides of the U and Th series, present in the phosphate rock used as raw material, which can impact the environment. In order to study the bioavailability of radionuclides, samples of phosphogypsum and phosphate fertilizers (monoammonium phosphate and triple superphosphate) were analyzed. The concentration of 226 Ra, 228 Ra and 210 Pb were determined by gamma spectrometry. The samples were leached with a mild EDTA solution and the radionuclides present in the final solution were determined by total alpha and beta counting on a gas flow proportional counter. The percentage of extraction varied from 1.6% to 1.7% for 210 Pb, from 0.5% to 1.4% for 226 Ra and from 0.1% to 1.0% for the 228 Ra in phosphogypsum samples. The low percentage of extraction obtained for the radionuclides can be partly explained by the low solubility of phosphogypsum, which ranged from 7.7% to 16%. For the monoammonium phosphate samples the percentage of extraction were less than 26% for 226 Ra, less than 10% for '2 28 Ra and less than 10% for 210 Pb. In spite of the high solubility of 77% of monoammonium phosphate in the EDTA solution, low concentrations of radionuclides were observed in the leached solution. For the triple superphosphate samples, the percentage of extraction was 2.3% for 226 Ra, 1.2% for 228 Ra and 11.3% for 210 Pb. In spite of the high solubility of 66% of triple superphosphate in the EDTA solution, low concentrations of radionuclides were observed in the leached solution. (author)

In situ gamma-ray spectrometric measurements of uranium in phosphates soil

International Nuclear Information System (INIS)

Lavi, N.; Ne'eman, E.; Brenner, S.; Haquin, G.; Nir-El, Y.

1997-01-01

Abstract Radioactivity concentration of 238 U in a phosphate ores quarry was measured in situ. Independently, soil samples collected in the site were measured in the laboratory. It was disclosed that radon emanation from the soil lowers in situ results that are derived from radon daughters. Uranium concentration was found to be 121.6±1.9 mg kg -1 (authors)

Enhancement of anamnestic immunospecific antibody response in orally immunized chickens

DEFF Research Database (Denmark)

Mayo, Susan; Carlsson, Hans-Erik; Zagon, Andrea

2008-01-01

Production of immunospecific egg yolk antibodies (IgY antibodies) in egg laying hens through oral immunization is an attractive alternative to conventional antibody production in mammals for economic reasons as well as for animal welfare reasons. Oral immunization results in a systemic humoral...... of the immunization in week 18, demonstrating the presence of memory cells following the two initial oral immunizations. Considering that oral immunization results in approximately ten times lower concentrations of immunospecific antibodies in the egg yolk, compared to traditional subcutaneous immunization schemes...

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.

Arbuscular mycorrhiza reduces phytoextraction of uranium, thorium and other elements from phosphate rock

International Nuclear Information System (INIS)

Roos, Per; Jakobsen, Iver

2008-01-01

Uptake of metals from uranium-rich phosphate rock was studied in Medicago truncatula plants grown in symbiosis with the arbuscular mycorrhizal fungus Glomus intraradices or in the absence of mycorrhizas. Shoot concentrations of uranium and thorium were lower in mycorrhizal than in non-mycorrhizal plants and root-to-shoot ratio of most metals was increased by mycorrhizas. This protective role of mycorrhizas was observed even at very high supplies of phosphate rock. In contrast, phosphorus uptake was similar at all levels of phosphate rock, suggesting that the P was unavailable to the plant-fungus uptake systems. The results support the role of arbuscular mycorrhiza as being an important component in phytostabilization of uranium. This is the first study to report on mycorrhizal effect and the uptake and root-to-shoot transfer of thorium from phosphate rock

Arbuscular mycorrhiza reduces phytoextraction of uranium, thorium and other elements from phosphate rock

Energy Technology Data Exchange (ETDEWEB)

Roos, Per [Radiation Research Department, Riso National Laboratory, Technical University of Denmark, DK-4000 Roskilde (Denmark); Jakobsen, Iver [Biosystems Department, Riso National Laboratory, Technical University of Denmark, DK-4000 Roskilde (Denmark)], E-mail: iver.jakobsen@risoe.dk

2008-05-15

Uptake of metals from uranium-rich phosphate rock was studied in Medicago truncatula plants grown in symbiosis with the arbuscular mycorrhizal fungus Glomus intraradices or in the absence of mycorrhizas. Shoot concentrations of uranium and thorium were lower in mycorrhizal than in non-mycorrhizal plants and root-to-shoot ratio of most metals was increased by mycorrhizas. This protective role of mycorrhizas was observed even at very high supplies of phosphate rock. In contrast, phosphorus uptake was similar at all levels of phosphate rock, suggesting that the P was unavailable to the plant-fungus uptake systems. The results support the role of arbuscular mycorrhiza as being an important component in phytostabilization of uranium. This is the first study to report on mycorrhizal effect and the uptake and root-to-shoot transfer of thorium from phosphate rock.

Evaluation and thermodynamic calculation of ureolytic magnesium ammonium phosphate precipitation from UASB effluent at pilot scale.

Science.gov (United States)

Desmidt, E; Ghyselbrecht, K; Monballiu, A; Verstraete, W; Meesschaert, B D

2012-01-01

The removal of phosphate as magnesium ammonium phosphate (MAP, struvite) has gained a lot of attention. A novel approach using ureolytic MAP crystallization (pH increase by means of bacterial ureases) has been tested on the anaerobic effluent of a potato processing company in a pilot plant and compared with NuReSys(®) technology (pH increase by means of NaOH). The pilot plant showed a high phosphate removal efficiency of 83 ± 7%, resulting in a final effluent concentration of 13 ± 7 mg · L(-1) PO(4)-P. Calculating the evolution of the saturation index (SI) as a function of the remaining concentrations of Mg(2+), PO(4)-P and NH(4)(+) during precipitation in a batch reactor, resulted in a good estimation of the effluent PO(4)-P concentration of the pilot plant, operating under continuous mode. X-ray diffraction (XRD) analyses confirmed the presence of struvite in the small single crystals observed during experiments. The operational cost for the ureolytic MAP crystallization treating high phosphate concentrations (e.g. 100 mg · L(-1) PO(4)-P) was calculated as 3.9 € kg(-1) P(removed). This work shows that the ureolytic MAP crystallization, in combination with an autotrophic nitrogen removal process, is competitive with the NuReSys(®) technology in terms of operational cost and removal efficiency but further research is necessary to obtain larger crystals.

Preliminary Screening Assessment of the Potential Impact of the Phosphate Fertilizer Industry on Wildlife

Energy Technology Data Exchange (ETDEWEB)

Vandenhove, Hildegarde; Sweeck, Lieve; Vives i Batlle, Jordi [SCK.CEN, Belgian Nuclear Research Centre, Boeretang 200, B-2400 Mol (Belgium)

2014-07-01

The activities of the phosphate industry may lead to enhanced levels of naturally occurring radioactivity in terrestrial and freshwater ecosystems. We here perform a preliminary environmental risk assessment (ERA) of the activities of the phosphate industry (phosphate ore mining, phosphate fertilizer factories, phosphate export platforms). We evaluated the environmental impact of 5 phosphate fertilizer plants (located in Belgium, Spain, Syria, Egypt, Brazil) and one phosphate-mine and phosphate-export platforms in the harbour(both located in Syria). These sites were selected because of the enhanced concentrations of naturally occurring radionuclides in the surrounding environments. The ERICA non-human biota assessment tool was used to predict radiation dose rates to the reference organisms and associated risks. Reference organisms were those assigned as default by the ERICA Tool. Potential impact is expressed as a risk quotient (RQ) based on a radiation screening value of 10 μGy h{sup -1}. If RQ ≤ 1, the environment is unlikely at risk and further radiological assessment is deemed not to be required. For all the cases assessed, RQ exceeded 1 for at least one of the reference organisms. {sup 226}Ra or {sup 210}Po were generally the highest contributors to the dose. The aquatic ecosystems in the vicinity of the phosphate fertilizer plants in Tessenderlo (Belgium), Huelva (Spain), Goias (Brazil) and the terrestrial environment around the phosphate mine in Palmyra (Syria) are the ecosystems predicted most at risk. (authors)

The Influence of Conditioning Agent on Phosphate Diffusion Coefficient through Polyacrylamide and Agarose Gel

Directory of Open Access Journals (Sweden)

Layta Dinira

2013-03-01

Full Text Available Excess phosphate in natural water can cause algae grow rapidly, to the extent causing many fish deaths that led to the extinction of certain species. Therefore, an analysis or periodic observations of phosphate levels in the water is needed. The commonly used method is diffusive gradient in thin films (DGT technique. The DGT technique is based on the ability of analyte to diffuse through a gel, which have a value named diffusion coefficient. This research was conducted in order to study the effect of different storage solution to the phosphate diffusion coefficient through polyacrylamide and agarose gels. Initial research performed with making the polyacrylamide and agarose gels. To observe the effect of different storage solutions, the gels partly stored in distilled water gel while the others are stored in a NaCl solution of 0.01 M. Phosphate diffusion coefficient was determined using Fick's Law after analyze the phosphate concentration using UV-Visible spectrophotometer. The results showed that phosphate diffusion coefficient was highest when polyacrylamide and agarose gels stored in NaCl solution of 0.01 M.

Contribution of Drinking Water Softeners to Daily Phosphate Intake in Slovenia

Directory of Open Access Journals (Sweden)

Gregor Jereb

2017-10-01

Full Text Available The cumulative phosphate intake in a typical daily diet is high and, according to several studies, already exceeds recommended values. The exposure of the general population to phosphorus via drinking water is generally not known. One of the hidden sources of phosphorus in a daily diet is sodium polyphosphate, commonly used as a drinking water softener. In Slovenia, softening of drinking water is carried out exclusively within the internal (household drinking water supply systems to prevent the accumulation of limescale. The aim of the study was to determine the prevalence of sodium phosphates in the drinking water in Slovenia in different types of buildings, to determine residents’ awareness of the presence of chemical softeners in their drinking water, and to provide an exposure assessment on the phosphorus intake from drinking water. In the current study, the presence of phosphates in the samples of drinking water was determined using a spectrophotometric method with ammonium molybdate. In nearly half of the samples, the presence of phosphates as water softeners was confirmed. The measured concentrations varied substantially from 0.2 mg PO4/L to 24.6 mg PO4/L. Nearly 70% of the respondents were not familiar with the exact data on water softening in their buildings. It follows that concentrations of added phosphates should be controlled and the consumers should be informed of the added chemicals in their drinking water. The health risks of using sodium polyphosphate as a drinking water softener have not been sufficiently investigated and assessed. It is highly recommended that proper guidelines and regulations are developed and introduced to protect human health from adverse effects of chemicals in water intended for human consumption.

Different effects of copper (II), cadmium (II) and phosphate on the sorption of phenanthrene on the biomass of cyanobacteria.

Science.gov (United States)

Tao, Yuqiang; Li, Wei; Xue, Bin; Zhong, Jicheng; Yao, Shuchun; Wu, Qinglong

2013-10-15

Due to the large surface area and high organic carbon content of cyanobacteria, organic contaminants can be readily sorbed on cyanobacteria during algal blooms, and then be transferred to the food web. This process is likely to be affected by the coexisting metals and nutrients, however, the possible impacts remain unclear. Effects of Cu(2+), Cd(2+), and phosphate on the sorption of phenanthrene on cyanobacterial biomass collected from an algal bloom were therefore studied. Continuous decrease in phenanthrene sorption was observed in the presence of low concentrations of Cu(2+), and Cd(2+) (phosphate concentration. Phosphate blocked the binding sites, modified the cell morphology, and increased the negative charge as well as the hydrophilicity of the cyanobacterial surface, thereby suppressing phenanthrene sorption. This study indicates that sorption of aromatic organic compounds by cyanobacteria could be significantly alerted by concentrations and properties of the coexisting transition metals and phosphates, which may subsequently affect their transfer to the food web in eutrophic waters. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.